2022/06/27 更新

写真a

コバヤシ マサカズ
小林 正和
所属
理工学術院 先進理工学部
職名
教授

兼担

  • 理工学術院   大学院先進理工学研究科

学内研究所等

  • 2020年
    -
    2022年

    理工学術院総合研究所   兼任研究員

学歴

  • 1983年04月
    -
    1988年03月

    東京工業大学   工学系研究科   電子物理工学  

  • 1979年04月
    -
    1983年03月

    早稲田大学   理工学部   電気工学科  

学位

  • 東京工業大学   工学博士

経歴

  • 2000年
    -
     

    早稲田大学   理工学術院   教授

  • 1991年
    -
    2000年

    千葉大学   工学部電気電子工学科   助教授

  • 1990年
    -
    1991年

    Purdue University   School of Electrical Engineering   主幹研究員

  • 1989年
    -
    1990年

    Purdue University   School of Electrical Engineering   客員助教授

  • 1988年
    -
    1989年

    Purdue University   School of Electrical Engineering   助手

所属学協会

  •  
     
     

    American Physical Society

  •  
     
     

    IEEE

  •  
     
     

    American Insitute of Physics

  •  
     
     

    電気学会

  •  
     
     

    応用物理学会

  •  
     
     

    Materials Research Society

▼全件表示

 

研究分野

  • 生体医工学

  • 生体材料学

  • 電気電子材料工学

  • 無機材料、物性

研究キーワード

  • 分子線エピタキシ 化合物半導体 ナノ粒子 光物性 電子物性 自家蛍光 分光画像解析、電子デバイス、固体物性Ⅰ(光物性・半導体・誘電体)、半導体物性

論文

  • Pursuit of single domain ZnTe layers on sapphire substrates

    Masakazu Kobayashi

    Journal of Crystal Growth   512   189 - 193  2019年04月

     概要を見る

    © 2019 ZnTe layers were grown on various orientation surfaces of sapphire substrates, namely c-, a-, r-, and S-planes. Single domain dominant layers were achieved by carefully controlling the substrate orientation and introducing the thin buffer layer. The substrate surfaces were annealed at approximately 1000 °C to achieve an atomically smooth surface with step-terrace structures. Single domain layers were achieved by employing the step-terrace structured substrates. A nanofacet structure of the substrate surface consisting of the r-plane and the S-plane was obtained by annealing the m-plane substrate surface. Nucleation of ZnTe occurred along the nanofacet. It was confirmed that preferential nucleation of ZnTe on the S-plane of the nanofacet took place. Nitrogen doping of the ZnTe layer was performed, with the doping efficiency confirmed as being as good as ZnTe layers prepared on GaAs substrates. This is another indication of the high crystal quality for the prepared ZnTe layer.

    DOI

  • The Optical Property Characterization of AgGaTe<inf>2</inf>Prepared by the Two-Step Closed Space Sublimation

    Aya Uruno, Masakazu Kobayashi

    Physica Status Solidi (A) Applications and Materials Science   216   592  2019年01月  [査読有り]

     概要を見る

    ? 2018 WILEY-VCH Verlag GmbH &amp; Co. KGaA, Weinheim Since its bandgap is close to optimum value, AgGaTe2is regarded as a promising material for solar cells. This paper reports the result of photoluminescence (PL) experiments on AgGaTe2thin films prepared by the two-step closed space sublimation method. In particular, the effect of by-products including Ag2Te or AgGa5Te8on PL properties of AgGaTe2is investigated. The radiative recombination process is also explored. PL measurements of thin films are performed by changing the excitation intensity and measured temperature. It is confirmed that the emission band probably derived from defects and impurities exists near 1.02 eV and the emission band derived from free exciton (FE) exists around 1.32 eV, and the variation of FE emission intensity is affected by the Ag/Ga ratio in AgGaTe2. It is also investigated that the activation energy (EA) of the FE emission is about 7.8 meV.

    DOI

  • The Growth of CuGaTe<inf>2</inf> Thin Films by Two-Step Closed Space Sublimation

    Aya Uruno, Masakazu Kobayashi

    Physica Status Solidi (A) Applications and Materials Science   216  2019年01月

     概要を見る

    © 2019 WILEY-VCH Verlag GmbH &amp; Co. KGaA, Weinheim CuGaTe2 layers are successfully grown on Si (001) and Mo/quartz substrates using two-step closed space sublimation (CSS). The surface morphology of the Cu2Te first layer is affected by the surface free energy of the different substrates. Cu2Te grown on Si (001) comprises hexagonal islands which are highly oriented to the (0001). Conversely, Cu2Te layers formed on Mo/quartz substrates forms a thin film. The surface morphology and the quality of the crystals in the CuGaTe2 layers are investigated. Overgrowth by CuGaTe2 of the Cu2Te islands on Si substrates is confined to the islands only and there is no nucleation on the bare substrate. On the contrary, overgrowth by CuGaTe2 on the continuous Cu2Te films on Mo/quartz substrates produces continuous thin films. Therefore, the surface morphology of the CuGaTe2 layers can be controlled by changing the substrate material because they have different surface free energies.

    DOI

  • Formation of AgGaTe2 films from (Ag2Te+Ga2Te3)/Ag2Te or Ga2Te3/Ag2Te bilayer structures

    Uruno Aya, Kobayashi Masakazu

    AIP ADVANCES   8 ( 11 ) 5023  2018年11月  [査読有り]

    DOI

  • The Crystal Quality and Surface Wettability of Various Tellurium-Based Chalcopyrite Layers Grown by the Closed Space Sublimation

    Aya Uruno, Yohei Sakurakawa, Masakazu Kobayashi

    Journal of Electronic Materials   47 ( 10 ) 1 - 5  2018年06月  [査読有り]

     概要を見る

    AgGaTe2, AgAlTe2, CuGaTe2, and Ag(Ga,Al)Te2 layers were deposited by the close spaced sublimation method. The surface morphology and crystal quality of these Te-based chalcopyrite layers were systematically evaluated. Controlling the stoichiometry of these layers grown by the closed space sublimation was very difficult because Te preferentially detached from the source materials during the sublimation process and then Te vapor leaked out from the reactor. To solve this problem, the gap between the lid and reactor boat was minimized, and the vapor was encapsulated. As a result, the crystal quality of the AgGaTe2 and AgAlTe2 was improved. However, the controlling stoichiometry of CuGaTe2 remained difficult even after the Te vapor leakage was minimized. This behavior was attributed to the large vapor pressure difference between Cu and Te. The surface morphology of the grown AgGaTe2 and CuGaTe2 layers exhibited scattered grain structure, while that of AgAlTe2 possessed a continuous film structure. These different surface structures contributed to differing wettability between the chalcopyrite materials and substrates. It was found that AgAlTe2 exhibited a high wettability against a sapphire substrate, which promoted continuous film formation.

    DOI

  • The growth of AgGaTe2 layer on Si substrate by two-step closed space sublimation and its application to solar cell fabrications

    Aya Uruno, Masakazu Kobayashi

    2017 IEEE 44th Photovoltaic Specialist Conference, PVSC 2017     1 - 6  2018年05月

     概要を見る

    The AgGaTe2 layer was formed on Ag2Te/Si structure with two different procedures by eliminating the melt-back etching. Diffusion of the Ga2Te3 source material into the Ag2Te layer and formation of the AgGaTe2 layer were both occurring during the growth when Ag2Te and Ga2Te3 source mixture was used to form AgGaTe2. It was also clear the AgGaTe2 could be formed by deposition and annealing of Ga2Te3 layer on top of the Ag2Te/Si structure. Solar cells were fabricated using the p-AgGaTe2/n-Si heterojunction, and showed conversion efficiency of approximately 3%.

    DOI

  • High-temperature fabrication of Ag(In,Ga)Se-2 thin films for applications in solar cells

    Xianfeng Zhang, Akira Yamada, Masakazu Kobayashi

    PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE   214 ( 10 )  2017年10月

     概要を見る

    Molecular beam epitaxy was used to fabricate Ag(In,Ga)Se-2 (AIGS) thin films. To improve the diffusion of Ag, high-temperature deposition and high-temperature annealing methods were applied to fabricate AIGS films. The as-grown AIGS thin films were then used to make AIGS solar cells. We found that grain size and crystallinity of AIGS films were considerably improved by increasing the deposition and annealing temperature. For high-temperature deposition, temperatures over 600 degrees C led to decomposition of the AIGS film, desorption of In, and deterioration of its crystallinity. The most appropriate deposition temperature was 590 degrees C and a solar cell with a power conversion efficiency of 4.1% was obtained. High-temperature annealing of the AIGS thin films showed improved crystallinity as annealing temperature was increased and film decomposition and In desorption were prevented. A solar cell based on this film showed the highest conversion efficiency of 6.4% when annealed at 600 degrees C. When the annealing temperature was further increased to 610 degrees C, the performance of the cell deteriorated due to loss of the out-of-plane Ga gradient.

    DOI

  • Effect of Sodium on the Properties of Ag(In, Ga)Se-2 Thin Films and Solar Cells

    Xianfeng Zhang, Masakazu Kobayashi

    IEEE JOURNAL OF PHOTOVOLTAICS   7 ( 5 ) 1426 - 1432  2017年09月

     概要を見る

    Ag(In, Ga)Se-2 (AIGS) thin films were deposited by a modified three-stage method, using a molecular beam epitaxy apparatus. The influence of sodium on the properties of AIGS films was investigated, using Mo-coated soda-lime-glass (SLG) and quartz as substrates. A sodium concentration gradient was observed along the thickness direction of the AIGS film. This resulted from sodium diffusion from the SLG substrate. No sodium was observed in the AIGS film fabricated on the quartz substrate. The grain size and crystallinity of AIGS increased upon sodium doping. Photoluminescence (PL) experiments on the AIGS film showed that exponentially tailed donor states introduced by indium atoms were passivated by sodium. This led to free excitons being observed in the PL spectrum. Potential fluctuation was used to explain the emission spectra of both sodium-containing and sodium-free samples. The donor and acceptor levels included in the quasi-donor-acceptor pair recombination were observed at approximately 35 meV interstitial defect (GaAg) and 100 meV (V-Se), respectively. Solar cell performance was significantly improved by sodium doping, probably because of defect passivation.

    DOI

  • Defect density reduction in core layer of ZnTe electro-optical waveguide by low lattice mismatched interfaces

    Wei-Che Sun, Taizo Nakusu, Keisuke Odaka, Masakazu Kobayashi, Toshiaki Asahi

    Journal of Vacuum Science and Technology B: Nanotechnology and Microelectronics   35 ( 4 )  2017年07月  [査読有り]

     概要を見る

    ZnTe electro-optic waveguide device has a great potential for the practical applications. The introduction of low Mg% cladding layer to the ZnMgTe/ZnTe/ZnMgTe waveguide structure was performed to circumvent the effect of large lattice mismatch between ZnMgTe and ZnTe, and to improve the crystallographic properties. Various two-step index ZnTe waveguide structures were fabricated by molecular beam epitaxy. The structure with 0.1 μm (Mg 9%) interlayer and 0.6 μm (Mg 26%) cladding layer showed significant defect density reduction compared to the single-step index ZnTe waveguide (Mg 20%) due the much smaller lattice mismatch between the ZnTe core layer and the ZnMgTe interlayer. However, the average Mg content of ZnMgTe layers needs to be carefully controlled to prevent the drop of the optical confinement.

    DOI

  • Nucleation of Cu2Te layer by a closed space sublimation method toward the growth of Te based chalcopyrite

    Yohei Sakurakawa, Aya Uruno, Masakazu Kobayashi

    Journal of Vacuum Science and Technology B: Nanotechnology and Microelectronics   35 ( 4 ) 106  2017年07月  [査読有り]

     概要を見る

    Nucleation of Cu-Te layers was performed by the closed space sublimation method using various source materials, source temperatures, and Si substrates with different surface orientations. The objective was to produce nuclei layers with high quality for use as nucleation centers for CuGaTe2. The grown samples were evaluated by x-ray diffraction and scanning electron microscopy. Cu2Te deposits were obtained using either a CuTe or Cu2Te source, but the latter gave a higher area coverage of Cu2Te nuclei. Highly oriented nuclei were obtained when they were grown on Si (001) at a source temperature of 640 °C and substrate temperature of 590 °C. When the source temperature was raised to 750 °C and the corresponding substrate temperature was 700 °C, nonuniform but highly oriented nuclei were obtained. Both nuclei layers exhibited a strong preference for (0001) orientation. The crystallographic features of the Cu2Te nuclei formed on Si (111) were similar to those of the Cu2Te nuclei formed on Si (001).

    DOI

  • Defect density reduction in core layer of ZnTe electro-optical waveguide by low lattice mismatched interfaces

    Wei-Che Sun, Taizo Nakusu, Keisuke Odaka, Masakazu Kobayashi, Toshiaki Asahi

    JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B   35 ( 4 )  2017年07月  [査読有り]

     概要を見る

    ZnTe electro-optic waveguide device has a great potential for the practical applications. The introduction of low Mg% cladding layer to the ZnMgTe/ZnTe/ZnMgTe waveguide structure was performed to circumvent the effect of large lattice mismatch between ZnMgTe and ZnTe, and to improve the crystallographic properties. Various two-step index ZnTe waveguide structures were fabricated by molecular beam epitaxy. The structure with 0.1 mu m ( Mg 9%) interlayer and 0.6 mu m ( Mg 26%) cladding layer showed significant defect density reduction compared to the single-step index ZnTe waveguide ( Mg 20%) due the much smaller lattice mismatch between the ZnTe core layer and the ZnMgTe interlayer. However, the average Mg content of ZnMgTe layers needs to be carefully controlled to prevent the drop of the optical confinement. (C) 2017 American Vacuum Society.

    DOI

  • Nucleation of Cu2Te layer by a closed space sublimation method toward the growth of Te based chalcopyrite

    Yohei Sakurakawa, Aya Uruno, Masakazu Kobayashi

    JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B   35 ( 4 )  2017年07月  [査読有り]

     概要を見る

    Nucleation of Cu-Te layers was performed by the closed space sublimation method using various source materials, source temperatures, and Si substrates with different surface orientations. The objective was to produce nuclei layers with high quality for use as nucleation centers for CuGaTe2. The grown samples were evaluated by x-ray diffraction and scanning electron microscopy. Cu2Te deposits were obtained using either a CuTe or Cu2Te source, but the latter gave a higher area coverage of Cu2Te nuclei. Highly oriented nuclei were obtained when they were grown on Si (001) at a source temperature of 640 degrees C and substrate temperature of 590 degrees C. When the source temperature was raised to 750 degrees C and the corresponding substrate temperature was 700 degrees C, nonuniform but highly oriented nuclei were obtained. Both nuclei layers exhibited a strong preference for (0001) orientation. The crystallographic features of the Cu2Te nuclei formed on Si (111) were similar to those of the Cu2Te nuclei formed on Si (001). (C) 2017 American Vacuum Society.

    DOI

  • Effect of Zn and Te beam intensity upon the film quality of ZnTe layers on severely lattice mismatched sapphire substrates by molecular beam epitaxy

    Taizo Nakasu, W. Sun, M. Kobayashi, T. Asahi

    JOURNAL OF CRYSTAL GROWTH   468   635 - 637  2017年06月  [査読有り]

     概要を見る

    Zinc telluride layers were grown on highly-lattice-mismatched sapphire substrates by molecular beam epitaxy, and their crystallographic properties were studied by means of X-ray diffraction pole figures. The crystal quality of the ZnTe thin film was further studied by scanning electron microscopy, X-ray rocking curves and low-temperature photoluminescence measurements. These methods show that high-crystallinity (111)-oriented single domain ZnTe layers with the flat surface and good optical properties are realized when the beam intensity ratio of Zn and Te beams is adjusted. The migration of Zn and Te was inhibited by excess surface material and cracks were appeared. In particular, excess Te inhibited the formation of a high-crystallinity ZnTe film. The optical properties of the ZnTe layer revealed that the exciton-related features were dominant, and therefore the film quality was reasonably high even though the lattice constants and the crystal structures were severely mismatched.

    DOI

  • Comparison of Ag(ln,Ga)Se-2/Mo and Cu(In,Ga)Se-2/Mo Interfaces in Solar Cells

    Xianfeng Zhang, Masakazu Kobayashi, Akira Yamada

    ACS APPLIED MATERIALS & INTERFACES   9 ( 19 ) 16215 - 16220  2017年05月

     概要を見る

    The structural and electrical properties of the junction at Ag(In,Ga)Se(2)AIGS/Mo, and Cu(In,Ga)Se-2 CIGS/Mo layers were characterized. The region between the CIGS and Mo featured a MoSe2 layer with a layered hexagonal structure and thickness of 10-15 nm. The c-axis of the MoSe2 was oriented perpendicular to the Mo layer, and the c-value was 12.6 A. However, no such layer was observed at the interface between AIGS and Mo. This result was also confirmed by energy-dispersive X-ray spectrometry and X-ray diffraction measurements of the MoSe2 layer. The GIGS/Mo with a MoSe2 layer formed an ohmic contact, while the AIGS/Mo without the MoSe2 layer formed a Schottky contact. This Schottky contact showed a barrier height of 0.8 +/- 0.02 eV, a nonideality factor of 1.5 +/- 0.1, and a series resistance of 370 +/- 8 Omega. A schematic band diagram of the AIGS/Mo junction was constructed on the basis of the above results.

    DOI

  • Growth and Crystal Orientation of ZnTe on m-Plane Sapphire with Nanofaceted Structure

    Taizo Nakasu, Wei-Che Sun, Masakazu Kobayashi, Toshiaki Asahi

    JOURNAL OF ELECTRONIC MATERIALS   46 ( 4 ) 2248 - 2253  2017年04月  [査読有り]

     概要を見る

    ZnTe thin films on sapphire substrate with nanofaceted structure have been studied. The nanofaceted structure of the m-plane (10-10) sapphire was obtained by heating the substrate at above 1100A degrees C in air, and the r-plane (10-12) and S-plane (1-101) were confirmed. ZnTe layers were prepared on the nanofaceted m-plane sapphire substrates by molecular beam epitaxy (MBE). The effect of the nanofaceted structure on the orientation of the thin films was examined based on x-ray diffraction (XRD) pole figures. Transmission electron microscopy (TEM) was also employed to characterize the interface structures. The ZnTe layer on the nanofaceted m-plane sapphire substrate exhibited (331)-plane orientation, compared with (211)-plane without the nanofaceted structure. After thermal treatment, the m-plane surface vanished and (211) layer could not be formed because of the lack of surface lattice matching. On the other hand, (331)-plane thin film was formed on the nanofaceted m-plane sapphire substrate, since the (111) ZnTe domains were oriented on the S-facet. The orientation of the ZnTe epilayer depended on the atomic ordering on the surface and the influence of the S-plane.

    DOI

  • Study on Growth Process of Ag(In, Ga)Se-2 Films by a Three-Stage Co-Evaporation Method Using Molecular Beam Epitaxy Apparatus

    Xianfeng Zhang, Masakazu Kobayashi

    IEEE PHOTONICS JOURNAL   9 ( 2 )  2017年04月

     概要を見る

    Ag(In, Ga)Se-2 (AIGS) has been considered as a promising candidate material for the top cell of chalcopyrite-based tandem solar cells. In this work, the process of (AIGS) film growth by a three-stage molecular beam epitaxy method is studied. The diffusion of silver and grain growth of AIGS films from the first stage-deposited (In, Ga)(2)Se-3 is investigated. Energy dispersive spectroscopy mapping is used to reveal the distribution of silver in the film during each stage of the deposition process. A sharp silver accumulation at the surface of the film at the early stage of the deposition process is observed. This has led to the formation of a silver-rich phase, which gradually diffused into the film to produce a homogeneous distribution. X-ray diffraction results illustrate the phase changes of AIGS films. Based on the result, a growth model for AIGS films from the first stage to the second stage is suggested as (In, Ga)(2)Se-3 -&gt; Ag-9 (In, Ga)Se-6 at the surface and (In, Ga)(2)Se-3 at the bottom of the film -&gt; silver-rich AIGS film. During the third stage, the silver-rich film was converted to silver-poor film. The performance of AIGS solar cells fabricated from various samples was compared, and a highest efficiency of 7.1% was obtained.

    DOI

  • Surface modification of a-plane sapphire substrates and its effect on crystal orientation of ZnTe layer

    Taizo Nakasu, Wei-Che Sun, Masakazu Kobayashi

    JAPANESE JOURNAL OF APPLIED PHYSICS   56 ( 1 )  2017年01月

     概要を見る

    Domain structures of ZnTe layers grown on a-plane sapphire substrates were investigated by changing the crystallographic properties of the surface and interface. Pole figure images were obtained and we investigated the domain structure in the grown film and the orientation relationships between films and substrates. It was confirmed that two kinds of {111} domains were oriented by annealing the buffer layer at 350 degrees C, while the (100) domain was obtained by annealing the buffer layer at 300 degrees C. From the results of the rocking curve measurement, the introduction of a step-terrace surface through the high-temperature treatment of the substrate resulted in an improved crystallographic quality. However, it did not affect the domain structure in the layer. The introduction of an off-angle on the substrate surface resulted in the formation of a single (111) domain layer. These crystallographic features were mainly affected by the surface atom arrangement of the sapphire substrate and its chemical nature. (C) 2017 The Japan Society of Applied Physics

    DOI

  • Structural and electric properties of AgGaTe2 layers prepared using mixed source of Ag2Te and Ga2Te3

    Aya Uruno, Masakazu Kobayashi

    PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE   214 ( 1 )  2017年01月  [査読有り]

     概要を見る

    AgGaTe2 layers were prepared on Si substrates by a closed space sublimation method using a mixed powder source of Ag2Te and Ga2Te3. Ag2Te buffer layer deposition was introduced to eliminate melt-back etching. The effect of the molar ratio of Ag2Te and Ga2Te3 in the mixed source on the crystallinity of the AgGaTe2 layer was investigated. The composition and the phase of the layer was found to change depending on the molar ratio in the deposits, which could be controlled by the source molar ratio along with the Ag2Te buffer layer thickness. It was confirmed that (112) oriented uniform AgGaTe2 layer with an abrupt interface between AgGaTe2 and Si was formed after those parameters were tuned. The obtained layer exhibited the acceptor concentration of around 2.5x10(16)cm(-3). A solar cell was fabricated using the p-AgGaTe2/n-Si heterojunction, and exhibited a conversion efficiency of 1.15%.

    DOI

  • Influence of Sapphire’s a-Plane on the Crystal Orientation of ZnTe thin films on Sapphire Substrates

    T. Nakasu, W. Sun, M. Kobayashi

    Japanese Journal of Applied Physics   56   15505  2017年  [査読有り]

  • Selective growth of ZnTe on sapphire substrates using a SiO2 mask

    Taizo Nakasu, Shota Hattori, Wei-Che Sun, Masakazu Kobayashi

    PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS   253 ( 11 ) 2265 - 2269  2016年11月

     概要を見る

    ZnTe/sapphire heterostructures have attracted attention for their suitable properties as a terahertz wave detector material. In this study, we focused on the selective growth of ZnTe on SiO2-masked sapphire substrates by molecular beam epitaxy (MBE). When ZnTe was grown at a high temperature (=350 degrees C), low growth rate (0.3mh(-1)), and low J(Te)/J(Zn) flux ratio (0.83) compared with the conventional film growth conditions, the formation of ZnTe nuclei on the SiO2 mask was avoided. The Te flux intensity significantly affected the selectivity of ZnTe growth. The selective growth of ZnTe on sapphire was revealed to be limited by the desorption of Te adatoms from the SiO2.

    DOI

  • Epitaxial Relationship Analysis Between ZnTe Epilayers and Sapphire Substrates

    Taizo Nakasu, Takayuki Aiba, Sotaro Yamashita, Shota Hattori, Takeru Kizu, Wei-Che Sun, Kosuke Taguri, Fukino Kazami, Yuki Hashimoto, Shun Ozaki, Masakazu Kobayashi, Toshiaki Asahi

    JOURNAL OF ELECTRONIC MATERIALS   45 ( 10 ) 4742 - 4746  2016年10月

     概要を見る

    Zinc telluride (ZnTe) epilayers were grown on S-plane (10 (1) over bar1) sapphire substrates by molecular beam epitaxy, and the epitaxial relationships between the two were compared with data previously obtained for layers grown on c-plane (0001), m-plane (10 (1) over bar 10) substrates, and r-plane (1 (1) over bar 02). The crystallographic relationship between the (111) plane of the ZnTe layer and (0001) plane of the substrate was studied using x-ray diffraction pole figure measurements. It was confirmed that two kinds of {111} oriented domains were formed on the S-plane substrate, and the dominant domain was (111)-oriented. Layers grown on S-plane substrate and on m-plane substrate exhibited the same epitaxial relationship, while the epitaxial relationship of the layer grown on the c-plane substrate exhibited a 60 degrees rotation. These findings would be applicable to control the orientation of ZnTe epilayer surface for various device applications and for various physical property characterizations.

    DOI

  • High-Quality AgGaTe2 Layers on Si Substrates with Ag2Te Buffer Layers

    Aya Uruno, Masakazu Kobayashi

    JOURNAL OF ELECTRONIC MATERIALS   45 ( 9 ) 4692 - 4696  2016年09月

     概要を見る

    AgGaTe2 layers were successfully grown on Si substrates by the close-spaced sublimation method. The Si substrates were confirmed to be etched during AgGaTe2 layer growth when the layer was grown directly on the substrate. To eliminate melt-back etching, a buffer layer of Ag2Te was introduced. It was found that the Ag2Te buffer layer changed into the AgGaTe2 layer during the growth process, and a uniform AgGaTe2 layer with an abrupt interface was formed. Both the diffusion of Ga into Ag2Te and the growth of AgGaTe2 occurred simultaneously. It was confirmed that uniform AgGaTe2 layers could be formed without any traces of the Ag2Te layer or melt-back etching by tuning the growth parameters. A solar cell was also fabricated using the p-AgGaTe2/n-Si heterojunction. This solar cell showed conversion efficiency of approximately 3%.

    DOI

  • Propagation loss reduction of ZnMgTe/ZnTe waveguide devices

    Wei-Che Sun, Fukino Kazami, Jing Wang, Taizo Nakasu, Shota Hattori, Takeru Kizu, Yuki Hashimoto, Masakazu Kobayashi, Toshiaki Asahi

    JAPANESE JOURNAL OF APPLIED PHYSICS   55 ( 8 )  2016年08月

     概要を見る

    A ZnMgTe/ZnTe electro-optic (EO) waveguide has great potential to be utilized for practical applications. A low-dislocation ZnMgTe/ZnTe waveguide can be fabricated when the cladding layer thickness is below 20-fold the calculated critical layer thickness (CCLT x 20). To improve optical confinement, a waveguide with a thicker cladding layer or a higher Mg% should be considered. However, the device performance might be affected because of crystal quality deterioration since the lattice mismatch between MgTe and ZnTe was around 4.1%. In this study, optical confinement and propagation loss were examined by changing the dimensions of the ZnMgTe/ZnTe waveguide structure. The propagation loss, EO characteristics, and crystal quality of the fabricated waveguides were mainly studied. A waveguide with a cladding layer thickness of around 1.5-fold the 1/e penetration depth of the evanescent wave (d(p1/e) x 1.5, corresponding to CCLT x 100) showed better optical properties than other waveguides, although its interface defect density was reasonably high. (C) 2016 The Japan Society of Applied Physics

    DOI

  • Surface Texture and Crystallinity Variation of ZnTe Epilayers Grown on the Step-Terrace Structure of the Sapphire Substrate

    Taizo Nakasu, Takeru Kizu, Sotaro Yamashita, Takayuki Aiba, Shota Hattori, Wei-Che Sun, Kosuke Taguri, Fukino Kazami, Yuki Hashimoto, Shun Ozaki, Masakazu Kobayashi, Toshiaki Asahi

    JOURNAL OF ELECTRONIC MATERIALS   45 ( 4 ) 2127 - 2132  2016年04月

     概要を見る

    ZnTe/sapphire heterostructures were focused, and ZnTe thin films were prepared on highly mismatched sapphire substrates by molecular beam epitaxy. A sapphire substrate possessing an atomically-smooth step-terrace structure was used to improve the crystallinity and morphology of the produced ZnTe film. The growth mode of the ZnTe thin film on a sapphire substrate with an atomically-smooth step-terrace structure was found to shift to a two-dimensional growth mode, and a ZnTe thin film possessing a flat surface was obtained. The crystallographic properties of the ZnTe film suggested that the resulting layer consisted of a single (111)-oriented domain. The photoluminescence property was also improved, and the interface lattice alignment between the ZnTe and sapphire was also affected by the atomically-smooth step-terrace structure.

    DOI

  • Influence of the lattice mismatch strain on the surface morphology of ZnMgTe/ZnTe/ZnMgTe electro-optical waveguide structure

    Fukino Kazami, Wei-Che Sun, Kosuke Taguri, Taizo Nakasu, Takayuki Aiba, Sotaro Yamashita, Shota Hattori, Takeru Kizu, Masakazu Kobayashi, Toshiaki Asahi

    PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS   253 ( 4 ) 635 - 639  2016年04月

     概要を見る

    ZnMgTe/ZnTe waveguide is a high potential electro-optical device. Thick and high Mg composition cladding layers are required for high optical performance waveguides. However, adding Mg would increase the lattice mismatch between ZnMgTe and ZnTe which would cause dislocation defects and generate asperities at interfaces. In this article, influence of the lattice mismatch strain to the waveguide surface morphology was studied. Waveguide structures were prepared by molecular beam epitaxy. The surface morphologies were observed using atomic force microscope and propagation loss of the waveguides were studied. Total of 0.5-0.7m asperities were observed on the surface of waveguides with 20% of Mg composition and 1.2m of the total cladding layer thickness. The asperities on the surface became larger (1.0-1.2m) when the Mg composition increased to 40%. The propagation loss of the waveguide was suppressed to 7dB by tuning the growth parameters and the resulting interface roughness.

    DOI

  • The growth process analysis of the ZnTe layer on the m-plane sapphire substrate with nano-facet structures

    T. Nakasu, T. Kizu, W. Sun, F. Kazami, M. Kobayashi, T. Asahi

    2016 COMPOUND SEMICONDUCTOR WEEK (CSW) INCLUDES 28TH INTERNATIONAL CONFERENCE ON INDIUM PHOSPHIDE & RELATED MATERIALS (IPRM) & 43RD INTERNATIONAL SYMPOSIUM ON COMPOUND SEMICONDUCTORS (ISCS)    2016年

     概要を見る

    ZnTe thin films were grown on m-plane sapphire substrates with nano-faceted structure by MBE. The growth process of the ZnTe thin film was analyzed by AFM. The influence of the nano-facet on the crystal quality of the epilayer was studied by means of XRD pole figure and PL measurements. It was confirmed that (331)-plane ZnTe layer was formed on the m-plane sapphire substrate with nano-faceted structure and the ZnTe epilayer grown of the nano-facet structure exhibited the single domain structure with high optical properties.

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  • Two-step-index ZnMgTe/ZnTe Waveguide Structures with Improved Crystal Quality

    Wei-Che Sun, Fukino Kazami, Jing Wang, Taizo Nakasu, Shota Hattori, Takeru Kizu, Yuki Hashimoto, Masakazu Kobayashi, Toshiaki Asahi

    MRS Advances   1 ( 23 ) 1721 - 1727  2016年

     概要を見る

    ZnMgTe(Cladding)/ZnTe(Core)/ZnMgTe(Cladding) thin film waveguide had been grown by molecular beam epitaxy (MBE) and presented a great potential to be a high performance Electro-optical (EO) modulator. For a low propagation loss ZnMgTe/ZnTe waveguide, thick cladding layer with high Mg composition (Mg %) is needed. However, the in-plane lattice mismatch of the fabricated device with high Mg % and thick cladding layer was large. It might cause the cladding/core interface roughness and asperities due to the misfit dislocation, and degrade the device performance. Because EO property of waveguide device is primarily influence by the structure thickness, the device efficiency improvement in this study was only considered to reduce the defects asperities that would cause propagation loss without decreasing the Mg % or the total thickness of the cladding layers. Therefore, we introduced a low Mg % layer between the cladding and the core layer to circumvent the effect of large lattice mismatch. The in-plane lattice mismatch of the devices was monitored using reciprocal space mapping, and surface morphologies were also observed using atom force microscope. The two-step index ZnMgTe/ZnTe waveguide had shown to have lower degree of relaxation compared to that of single-step index waveguide device with close Mg % and cladding layer thickness. Therefore, the crystal degradation of the two-step-index waveguide caused by lattice mismatch was successfully suppressed by introduction extra low Mg % layers. The morphologies of the two kinds of waveguide structures have similar surface asperities, which indicated the extra inserted layers did not produce additional large scale asperities at the interfaces that would increase the propagation loss.

    DOI

  • Crystallographic and optical characterizations of Ag(Ga,Al)Te-2 layers grown on c-plane sapphire substrates by closed space sublimation

    Aya Uruno, Yuji Takeda, Tomohiro Inoue, Masakazu Kobayashi

    PHYSICA STATUS SOLIDI C: CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 13 NO 7-9   13 ( 7-9 ) 413 - 416  2016年

     概要を見る

    Ag(Ga,Al)Te-2 layers were grown by the closed space sublimation method on c-plane sapphire substrates. The source used was AgAlTe2/AgGaTe2 mixture or AgAlTe2/Ga2Te3 mixture. The crystallographic property of Ag(Ga,Al)Te-2 layers was analyzed by X-ray diffraction (XRD). XRD spectra of layers exhibited very strong 112 diffraction peaks regardless of the variation of the source material mixture. In addition to crystallographic characterizations, optical properties of the Ag(Ga,Al)Te-2 layer were evaluated through transmittance measurements. The bandgap energy was decreased when the source mole ratio of Al to Ga was decreased. It was revealed that control regulation of x composition of Ag(Ga1-x,Al-x)Te-2 was feasible by varying the source mole ratio Al/(Ga+Al). (C) 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

    DOI

  • ZnTe layers on R- and S-plane sapphire substrates

    Taizo Nakasu, Shota Hattori, Takeru Kizu, Wei-Che Sun, Fukino Kazami, Yuki Hashimoto, Masakazu Kobayashi, Toshiaki Asahi

    PHYSICA STATUS SOLIDI C: CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 13 NO 7-9   13 ( 7-9 ) 435 - 438  2016年

     概要を見る

    ZnTe epilayers were grown on R-plane (10 (1) over bar4) and S-plane (10 (1) over bar1) sapphire substrates by molecular beam epitaxy, and the crystal orientation and the optical property were studied. The crystal orientation of ZnTe layers on sapphire substrates was studied using X-ray diffraction pole figure measurements. It was confirmed that (111)-oriented domains were formed on the R-plane as well as on the S-plane substrate. Layers grown on R-plane exhibited higher film quality. From the lowtemperature photoluminescence, emissions caused by ZnTe exciton were observed. (C) 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

    DOI

  • Study of the Growth Mechanism of Cu2ZnSnS4 Films Fabricated by Nanoparticle during the Annealing Process

    Xingfeng Zhang, Masakazu Kobayashi

    2016 PROGRESS IN ELECTROMAGNETICS RESEARCH SYMPOSIUM (PIERS)     2306 - 2309  2016年

     概要を見る

    Cu2ZnSnS4 (CZTS) precursor was fabricated from a CZTS nano crystal ink, which was obtained by a ball-milling method. The precursor was then annealed in the sulfur atmosphere. The growth mechanism of CZTS was studied in this work. It was found that with the extension of annealing time, the grain size as well as the crystallinity was improved significantly. And growth of grains from domain area of CZTS nano particles was observed. The samples experienced a decomposition process during the annealing. Secondary phases, such as ZnS, SnS, CuS and CuSnS3, were detected at the beginning of annealing process. However, with the increase of annealing time, the secondary phases recombined to form uniform CZTS film, which lead to the growth of grain size and improvement of crystallinity. The growth mechanism of CZTS films during the annealing process was concluded as: CZTS(Nanoparticle)-&gt;(Cu2S, ZnS, SnxS)-&gt; CZTS (large grains).

    DOI

  • The Growth of AgGaTe2 Layer on Si Substrate by Two-Step Closed Space Sublimation and its Application to Solar Cell Fabrications

    Aya Uruno, Masakazu Kobayashi

    2016 IEEE 43RD PHOTOVOLTAIC SPECIALISTS CONFERENCE (PVSC)   2016-November   524 - 529  2016年

     概要を見る

    The AgGaTe2 layer was formed on Ag2Te/Si structure with two different procedures by eliminating the melt-back etching. Diffusion of the Ga2Te3 source material into the Ag2Te layer and formation of the AgGaTe2 layer were both occurring during the growth when Ag2Te and Ga2Te3 source mixture was used to form AgGaTe2. It was also clear the AgGaTe2 could be formed by deposition and annealing of Ga2Te3 layer on top of the Ag2Te/Si structure. Solar cells were fabricated using the p-AgGaTe2/n-Si heterojunction, and showed conversion efficiency of approximately 3%.

    DOI

  • Growth and characterization of ZnTe layers on severely lattice mismatched sapphire substrates by MBE

    T. Nakasu, W. Sun, M. Kobayashi, T. Asahi

    Journal of Crystal Growth   ( 11 ) 35  2016年  [査読有り]

    DOI

  • Cu2ZnSn(S,Se)(4) thin films prepared using Cu2ZnSnS4 nanoparticles

    Shunya Taki, Yuto Umejima, Aya Uruno, Xianfeng Zhang, Masakazu Kobayashi

    2016 IEEE 16TH INTERNATIONAL CONFERENCE ON NANOTECHNOLOGY (IEEE-NANO)     699 - 702  2016年

     概要を見る

    Cu2ZnSn(S,Se)(4) (CZTSSe) is a compound semiconductor which replaces a part of S in the CZTS crystal by Se. The bandgap varies from 1.05 eV to 1.51 eV depending on the mole ratio between S and Se. In this paper, CZTSSe thin films were prepared by the selenidation of CZTS film, and the Se mole ratio was tuned by changing annealing conditions. The film quality of the obtained CZTSSe was characterized by X-ray diffraction (XRD) and Hall measurements. It was revealed that both the supply of Se vapor pressure and the annealing temperature of CZTS were controlling parameters for the selenidation of the film. The crystal quality of CZTSSe was also influenced by the supply of Se vapor pressure.

    DOI

  • Growth and Solar Cell Applications of AgGaTe2 layers by Closed Space Sublimation using the Mixed Source of Ag-2 Te and Ga-2 Te-3

    Aya Uruno, Shinichiro Kikai, Yuri Suetsugu, Masakazu Kobayashi

    2016 COMPOUND SEMICONDUCTOR WEEK (CSW) INCLUDES 28TH INTERNATIONAL CONFERENCE ON INDIUM PHOSPHIDE & RELATED MATERIALS (IPRM) & 43RD INTERNATIONAL SYMPOSIUM ON COMPOUND SEMICONDUCTORS (ISCS)    2016年  [査読有り]

  • Control of domain orientation during the MBE growth of ZnTe on a-plane sapphire

    T. Nakasu, T. Aiba, S. Yamashita, S. Hattori, W. Sun, K. Taguri, F. Kazami, M. Kobayashi, T. Asahi

    JOURNAL OF CRYSTAL GROWTH   425   191 - 194  2015年09月

     概要を見る

    ZnTe epilayers were grown on transparent a-plane (11-20) sapphire substrates by molecular beam epitaxy (MBE). The insertion of a low temperature nucleated buffer layer was carried out, and the influence of the buffer layer annealing prior to the film growth on crystallographic properties of the epilayer was investigated. Pole figure imaging and wide range reciprocal space mapping (RSM) measurements were used to study the domain distribution within the layer, and epitaxial relationships between the ZnTe thin films and the sapphire substrates. The orientation of ZnTe domains formed on a-plane sapphire substrates was controlled by the annealing condition of the buffer layer. Two different {111} domains were formed from the sample the buffer layer was annealed at 350 degrees C. while (100) layers were obtained from the sample the buffer layer was annealed at 300 degrees C. These crystallographic features were probably originated from the atom arrangements of ZnTe and sapphire at the interface. (C) 2015 Elsevier B.V. All rights reserved.

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  • Crystallographic Characterization of AgGaTe2, AgAlTe2, and Ag(Ga,Al)Te-2 Grown by Closed-Space Sublimation

    Aya Uruno, Ayaka Usui, Tomohiro Inoue, Yuji Takeda, Masakazu Kobayashi

    JOURNAL OF ELECTRONIC MATERIALS   44 ( 9 ) 3013 - 3017  2015年09月

     概要を見る

    AgGaTe2, AgAlTe2, and Ag(Ga,Al)Te-2 layers were grown by the closed-space sublimation method on c-plane sapphire substrates. The crystallographic properties of the AgGaTe2 and AgAlTe2 layers were then analyzed by x-ray diffraction (XRD). Very strong 112 diffraction peaks were observed in the XRD spectra of both layers, and it was clear the (112) orientation was predominant in both layers. The orientation and domain structure of the AgAlTe2 layer were carefully analyzed by XRD pole-figure measurement, and the effect of substrate surface atomic arrangement on the crystallinity of the AgAlTe2 layer was investigated. On the basis of the pole-figure image, six types of {112} domain were confirmed in the layer, and [ 10] in one domain was regarded as aligned with the sapphire's a-axis when the layer was formed on the c-plane sapphire substrate surface. In addition to crystallographic characterization, the optical properties of the Ag(Ga,Al)Te-2 layer were evaluated on the basis of transmittance measurements. The optical bandgap, derived from the transmittance spectrum, was approximately 2.0 eV. This value was between the bandgap values of AgGaTe2 and AgAlTe2. These results showed that an alloy of AgGaTe2 and AgAlTe2 had been grown successfully.

    DOI

  • Growth of ZnTe epilayers on r- and n-plane sapphire substrates

    Taizo Nakasu, Takayuki Aiba, Sotaro Yamashita, Shota Hattori, Takeru Kizu, Wei-Che Sun, Kosuke Taguri, Fukino Kazami, Masakazu Kobayashi

    JAPANESE JOURNAL OF APPLIED PHYSICS   54 ( 7 )  2015年07月

     概要を見る

    ZnTe epilayers were grown on r-plane (1102) and n-plane (1123) sapphire substrates by molecular beam epitaxy. The ZnTe domain distribution in the layer and the influence of the substrates' c-plane location on the orientation of the epilayer were studied by means of X-ray diffraction pole figure measurements. Computer simulation was used to analyze the diffraction patterns. The (100)-plane ZnTe was formed on the r-plane substrate whereas two different {111}-plane mixed with the (511) domain were formed on n-plane substrate, respectively. The orientation of ZnTe layers on r-plane sapphire substrates could not change even by varying the buffer layer growth condition. From these results, it was revealed that the relationship of the sapphire c-plane and the (111) ZnTe strongly affected the orientation of the film. ZnTe layers grown on n-plane sapphire substrates, on the other hand, exhibited different relationships and (111) of ZnTe was not aligned to the sapphire c-plane. (C) 2015 The Japan Society of Applied Physics

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  • The growth of AgGaTe2 layers on glass substrates with Ag2Te buffer layer by closed space sublimation method

    Aya Uruno, Ayaka Usui, Yuji Takeda, Tomohiro Inoue, Masakazu Kobayashi

    PHYSICA STATUS SOLIDI C: CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 12, NO 6   12 ( 6 ) 508 - 511  2015年

     概要を見る

    The AgGaTe2 layer growth was performed by the closed space sublimation method on the Mo/glass substrate. The Ag2Te buffer layer was inserted between AgGaTe2 and Mo layers, to improve the quality of grown layers. Crystallographic properties were analyzed by x-ray diffraction (XRD), and the surface morphologies were analyzed by scanning electron microscopy (SEM). The Ag2Te layer grown on the Mo/glass exhibited a membrane filter structure from the SEM observation. XRD spectra of layers grown with and without the buffer layer were compared. The AgGaTe2 layer with the Ag2Te buffer layer exhibited peaks originating from AgGaTe2, and a very strong diffraction peak of 112 was observed. On the other hand, it was cleared that the layer grown without the buffer layer exhibited no strong peaks associated with AgGaTe2, but Ga-Te compounds. From this, crystallographic properties of the AgGaTe2 layer were drastically improved by the insertion of the Ag2Te buffer layer. Moreover, the surface morphology exhibited a smooth surface when the Ag2Te buffer layer was inserted. The nucleation site density of AgGaTe2 was probably increased since the membrane filter structure exhibited numbers of kinks at the edge. Chemical reaction between Ga and Mo was also eliminated. It was cleared that the insertion of the buffer layer and its surface morphology were an important parameter to grow high quality AgGaTe2 layers.

    DOI

  • Structural and optical properties of AgAlTe2 layers grown on sapphire substrates by closed space sublimation method

    A. Uruno, A. Usui, M. Kobayashi

    JOURNAL OF APPLIED PHYSICS   116 ( 18 )  2014年11月

     概要を見る

    AgAlTe2 layers were grown on a-and c-plane sapphire substrates using a closed space sublimation method. Grown layers were confirmed to be single phase layers of AgAlTe2 by X-ray diffraction. AgAlTe2 layers were grown to have a strong preference for the (112) orientation on both kinds of substrates. The variation in the orientation of grown layers was analyzed in detail using the X-ray diffraction pole figure measurement, which revealed that the AgAlTe2 had a preferential epitaxial relationship with the c-plane sapphire substrate. The atomic arrangement between the (112) AgAlTe2 layer and sapphire substrates was compared. It was considered that the high order of the lattice arrangement symmetry probably effectively accommodated the lattice mismatch. The optical properties of the grown layer were also evaluated by transmittance measurements. The bandgap energy was found to be around 2.3 eV, which was in agreement with the theoretical bandgap energy of AgAlTe2. (C) 2014 AIP Publishing LLC.

    DOI

  • Crystal orientation mechanism of ZnTe epilayers formed on different orientations of sapphire substrates by molecular beam epitaxy

    T. Nakasu, S. Yamashita, T. Aiba, S. Hattori, W. Sun, K. Taguri, F. Kazami, M. Kobayashi

    JOURNAL OF APPLIED PHYSICS   116 ( 16 )  2014年10月

     概要を見る

    The electrooptic effect in ZnTe has recently attracted research attention, and various device structures using ZnTe have been explored. For application to practical terahertz wave detector devices based on ZnTe thin films, sapphire substrates are preferred because they enable the optical path alignment to be simplified. ZnTe/sapphire heterostructures were focused upon, and ZnTe epilayers were prepared on highly mismatched sapphire substrates by molecular beam epitaxy. Epitaxial relationships between the ZnTe thin films and the sapphire substrates with their various orientations were investigated using an X-ray diffraction pole figure method. (0001) c-plane, (1-102) r-plane, (1-100) m-plane, and (11-20) a-plane oriented sapphire substrates were used in this study. The epitaxial relationship between ZnTe and c-plane sapphire was found to be (111) ZnTe//(0001) sapphire with an in-plane orientation relationship of [-211] ZnTe//[1-100] sapphire. It was found that the (211)-plane ZnTe layer was grown on the m-plane of the sapphire substrates, and the (100)-plane ZnTe layer was grown on the r-plane sapphire. When the sapphire substrates were inclined from the c-plane towards the m-axis direction, the orientation of the ZnTe thin films was then tilted from the (111)-plane to the (211)-plane. The c-plane of the sapphire substrates governs the formation of the (111) ZnTe domain and the ZnTe epilayer orientation. These crystallographic features were also related to the atom arrangements of ZnTe and sapphire. (C) 2014 AIP Publishing LLC.

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  • Growth of AgGaTe2 and AgAlTe2 Layers for Novel Photovoltaic Materials

    Aya Uruno, Ayaka Usui, Masakazu Kobayashi

    JOURNAL OF ELECTRONIC MATERIALS   43 ( 8 ) 2874 - 2878  2014年08月

     概要を見る

    AgGaTe2 and AgAlTe2 layers were grown on a-plane sapphire substrates by closed-space sublimation. These compounds replace Cd in CdTe with group I and III elements, and are, hence, expected to be ideal novel candidate materials for solar cells. The grown layers were confirmed to be stoichiometric AgGaTe2 and AgAlTe2 by x-ray diffraction (XRD). The AgAlTe2 layers had strong preference for the (112) orientation. The XRD spectrum of the AgGaTe2 layer was different from that of the AgAlTe2 layer, and strong peaks were observed for (103) and (110) diffraction. The variation in orientations of the grown layers was analyzed in detail by use of XRD pole figures, which revealed that the AgGaTe2 layers had an epitaxial relationship with the a-plane sapphire substrates.

    DOI

  • (211)-Oriented Domain Formation During Growth of ZnTe on m-Plane Sapphire by MBE

    Taizo Nakasu, Masakazu Kobayashi, Hiroyoshi Togo, Toshiaki Asahi

    JOURNAL OF ELECTRONIC MATERIALS   43 ( 4 ) 921 - 925  2014年04月

     概要を見る

    ZnTe epilayers have been grown on 2A degrees-tilted m-plane sapphire substrates by molecular beam epitaxy. Pole figure imaging was used to study the domain distribution within the layer, and the pole figures of 111, 220, 004, and 422 ZnTe and sapphire were measured. Computer simulation was used to analyze the symmetry of the diffraction patterns seen in the pole figure images. Stereographic projections were also compared with the pole figures of 422 and 211 ZnTe, confirming that single-domain (211)-oriented ZnTe epilayers had been grown on the 2A degrees-tilted m-plane sapphire substrates. Although differences in crystal structure and lattice mismatch were severe in these heterostructures, precise control of the substrate surface's lattice arrangement would result in the formation of high-quality epitaxial layers.

    DOI

  • and electro-optical characterization of ZnMgTe/ZnTe waveguide by molecular beam epitaxy

    W. Sun, T. Nakasu, K. Taguri, T. Aiba, S. Yamashita, M. Kobayashi, H. Togo, T. Asahi

    PHYSICA STATUS SOLIDI C: CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 11, NO 7-8   11 ( 7-8 ) 1252 - 1255  2014年

     概要を見る

    ZnMgTe/ZnTe/ZnMgTe thin film waveguide with high crystal quality were grown by molecular beam epitaxy (MBE). The in-plane mismatch between the ZnMgTe cladding layers and ZnTe core layer was about 0.02% which was measured by X-ray reciprocal space mapping (RSM). It indicated that films were grown coherently with high crystal quality. The Electro-Optical characterization of waveguide was evaluated using 1.55 mu m polarized lights and bias applied on the waveguide device from -15 V to + 15 V. The dependence of light phase shift passed though the waveguide on the applied voltage bias was studied. The electro-optical characterization of the waveguide device was about 7% of the theoretical calculation. It could be improved by increasing the resistance ratio between the ZnMgTe/ZnTe/ZnMgTe waveguide structure and substrate so that the electric field applied on the waveguide structure could be improved. It was indicated that the ZnMgTe/ZnTe/ZnMgTe thin film waveguide has the potential to become a high efficiency electro-optical device. (C) 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

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  • MBE growth and characterization of ZnTe epilayers on m-plane sapphire substrates

    Taizo Nakasu, Wei-Che Sun, Sotaro Yamashita, Takayuki Aiba, Kosuke Taguri, Masakazu Kobayashi, Toshiaki Asahi, Hiroyoshi Togo

    PHYSICA STATUS SOLIDI C: CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 11, NO 7-8   11 ( 7-8 ) 1182 - 1185  2014年

     概要を見る

    ZnTe epilayers were grown on transparent (10-10) oriented (m-plane) sapphire substrates by molecular beam epitaxy (MBE). Pole figure imaging was used to study the domain distribution within the layer. (211)-oriented ZnTe domains were formed on m-plane sapphire. The presence of only one kind of (211) ZnTe domain formed on the 2 degrees-tilted m-plane sapphire substrates was con-firmed. Thus, single domain (211) ZnTe epilayers can be grown on the m-plane sapphire using MBE. Although differences in the crystal structure and lattice mismatch are large, precise control of the substrate surface lattice arrangement result in the formation of high-quality epitaxial layers. (C) 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

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  • Structural characterization of AgGaTe2 layers grown on a- and c-sapphire substrates by a closed space sublimation method

    Aya Uruno, Ayaka Usui, Masakazu Kobayashi

    PHYSICA STATUS SOLIDI C: CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 11, NO 7-8   11 ( 7-8 ) 1186 - 1189  2014年

     概要を見る

    AgGaTe2 layers were grown on a-and c-plane sapphire substrates by a closed space sublimation method with varying the source temperature. Grown films were evaluated by theta-2 theta and pole figure measurements of X-ray diffraction. AgGaTe2 layers were grown to have strong preference for the (103) orientation. However, it was cleared the Ag5Te3 was formed along with the AgGaTe2 when the layer was grown on c-plane sapphire. The orientation of the film was analyzed by using the pole figure, and resulted in AgGaTe2 without Ag5Te3 layers could be grown on a-plane sapphire. (C) 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

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  • Molecular beam epitaxy growth and pole figure analysis of ZnTe epilayer on m-plane sapphire

    Taizo Nakasu, Masakazu Kobayashi, Toshiaki Asahi, Hiroyoshi Togo

    JAPANESE JOURNAL OF APPLIED PHYSICS   53 ( 1 )  2014年01月

     概要を見る

    ZnTe epilayers were grown on transparent (10 (1) over bar0) oriented (m-plane) sapphire substrates by molecular beam epitaxy (MBE). The insertion of a low-temperature buffer layer was carried out, and the influence of the buffer layer annealing on crystallographic properties was investigated. Pole figure imaging was used to study the domain distribution in the layer. It was shown that strongest (211)- and (100)-oriented ZnTe epilayers were formed on m-sapphire when a ZnTe buffer layer annealed at 340 degrees C for 5-min was inserted. Also, it was confirmed that only (211) ZnTe epilayers were formed on the 2 degrees tilted m-plane sapphire substrate. Thus, the single domain (211) ZnTe epilayer can be grown on the m-plane sapphire using MBE. (C) 2014 The Japan Society of Applied Physics

    DOI

  • Growth of CuGaTe2 based compounds by a closed space sublimation method

    Ayaka Usui, Aya Uruno, Masakazu Kobayashi

    PHYSICA STATUS SOLIDI C: CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 11, NO 7-8   11 ( 7-8 ) 1190 - 1193  2014年

     概要を見る

    Chalcopyrite I-III-VI2 compounds are considered as novel potential materials for solar cells. Among the variety of those compounds, CuGaTe2 and AgAlTe2 films were grown by a closed space sublimation method. Crystallinity and stoichiometry of grown films were evaluated by X-ray diffraction measurements. When CuGaTe2 powder source was used to grow CuGaTe2 films at around 840 degrees C of the source temperature, stoichiometric CuGaTe2 could not be formed. X-ray diffraction measurements revealed that the deposited material was Cu-Ga compound. The desorption of Te was compensated by adding elemental Te in the source material. These stoichiometric CuGaTe2 films were achieved when the volume of additional Te was around twice weight of CuGaTe2. On the other hand, growth of AgAlTe2 films could be achieved when the source temperature was 800 degrees C, and no additional Te was introduced in the source. From X-ray diffraction measurements, it was found that these two compounds films had strong preference for the (112) orientation on the quartz substrate. (C) 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

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  • Growth of AgGaTe2 on a- and c-plane sapphire by closed-space sublimation and analysis of the orientation by pole figure measurement

    Aya Uruno, Ayaka Usui, Masakazu Kobayashi

    JAPANESE JOURNAL OF APPLIED PHYSICS   53 ( 1 )  2014年01月

     概要を見る

    AgGaTe2 layers were grown on a- and c-plane sapphire substrates by a closed-space sublimation method. Various samples have been prepared with various source temperatures, holding times, and temperature differentials. In this study,. the variation of source temperature was primarily aimed at improving the stoichiometry of the film. The grown films were evaluated by X-ray diffraction (XRD) measurements. When the sample was grown at a high temperature, namely, above 800 degrees C, the formation of Ag-Te compounds was observed. The Ag-Te compounds exhibited a high degree of crystallinity when the layer was grown on c-plane sapphire substrates. By using a pole figure, it was possible to study the orientation of the film, and AgGaTe2 layers were shown to have a preferential orientation in the (103) on a-sapphire. (C) 2014 The Japan Society of Applied Physics

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  • Growth of AgGaTe

    Uruno Aya, Usui Ayaka, Kobayashi Masakazu

    Jpn. J. Appl. Phys.   53 ( 1 ) 15501 - 15501  2013年12月

    DOI CiNii

  • Growth of AgGaTe2 Layers by a Closed-Space Sublimation Method

    Aya Uruno, Masakazu Kobayashi

    JOURNAL OF ELECTRONIC MATERIALS   42 ( 5 ) 859 - 862  2013年05月

     概要を見る

    AgGaTe2 layers were deposited on Si substrates by the closed-space sublimation method. Multiple samples were deposited with various source temperatures and holding times, and constant temperature differential. Variation of the source temperature was used primarily to improve the stoichiometry of the film. Deposited films were evaluated by the theta-2 theta method of x-ray diffraction (XRD) and transmission electron microscopy. These results confirmed that the deposited films were stoichiometric (after optimizing the above parameters). From XRD, it was also clear that films deposited on Si (111) have strong preference for (112) orientation.

    DOI

  • Deposition of AgGaTe2 on sapphire substrates by closed space sublimation

    Aya Uruno, Ayaka Usui, Masakazu Kobayashi

    PHYSICA STATUS SOLIDI C: CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 10, NO 11   10 ( 11 ) 1389 - 1392  2013年

     概要を見る

    AgGaTe2 layers were grown on a-plane sapphire substrates by a closed space sublimation method. Various samples were prepared with varied source temperature, holding time and temperature differential. The variation of source temperature was used primarily to improve the stoichiometry of the film. Grown films were evaluated by XRD measurements. AgGaTe2 layers were grown only at low source temperature (about 780 degrees C), and to have strong preference for the (103) orientation. By using the pole figure, it is possible to study the orientation of the film, and the substrate surface arrangement has resulted in this unique relationship. (C) 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

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  • (211) oriented ZnTe growth on m-plane sapphire by MBE

    Taizo Nakasu, Masakazu Kobayashi, Hiroyoshi Togo, Toshiaki Asahi

    PHYSICA STATUS SOLIDI C: CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 10, NO 11   10 ( 11 ) 1381 - 1384  2013年

     概要を見る

    Single-crystalline and single domain ZnTe thin films are sought for high-performance terahertz wave detectors, and ZnTe/sapphire heterostructures were considered since the Electro-Optical (EO) effect could be obtained only from epilayers. ZnTe epilayers were grown on m-plane sapphire substrates by molecular beam epitaxy, and the potential of single domain epilayers was explored. Through the X-ray diffraction pole figure measurement it was confirmed that one (100) oriented ZnTe domain along with two kinds of (211) oriented domains were formed on the m-plane sapphire when the layer was grown at 340 degrees C. When the layer was grown at 350 degrees C, the (211) oriented domain dominated the film. (C) 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

    DOI

  • Molecular Beam Epitaxy Growth of ZnTe Epilayers on c-Plane Sapphire

    Taizo Nakasu, Yuki Kumagai, Kimihiro Nishimura, Masakazu Kobayashi, Hiroyoshi Togo, Toshiaki Asahi

    APPLIED PHYSICS EXPRESS   5 ( 9 )  2012年09月

     概要を見る

    ZnTe epilayers were grown on transparent substrates by molecular beam epitaxy. The insertion of a low-temperature buffer layer was carried out, and the influence of the buffer layer thickness and its annealing on the crystallographic property were investigated. Pole figure imaging was used to study the domain distribution in the layer. It was shown that the (111) ZnTe epilayer with the decreased number of domains could be formed on c-sapphire when a 3.5-nm-thick annealed ZnTe buffer layer was inserted. It was shown that the XRD pole figure imaging was a useful means of analyzing domain distributions in the film. (C) 2012 The Japan Society of Applied Physics

    DOI

  • Growth of ZnMgTe/ZnTe Waveguide Structures and Analysis of the Light Polarization with the Electric Field

    Yuki Kumagai, Masakazu Kobayashi

    JAPANESE JOURNAL OF APPLIED PHYSICS   51 ( 2 )  2012年02月

     概要を見る

    The electro-optical (EO) effect of the ZnMgTe/ZnTe waveguide structure grown on (001) ZnTe single crystal substrates using molecular beam epitaxy (MBE) was studied. The EO properties of ZnTe were investigated by optical confinement with an electric field. The effect of the applied electric field and the rotation of polarization wave effect are discussed. (C) 2012 The Japan Society of Applied Physics

    DOI

  • X-ray pole figure analysis of ZnTe layers grown on lattice mismatched substrates

    Masakazu Kobayashi, Yuki Kumagai, Toshiaki Baba, Shota Imada

    PHYSICA STATUS SOLIDI C: CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 9, NO 8-9   9 ( 8-9 ) 1748 - 1751  2012年

     概要を見る

    The electro-optical effect of ZnTe is recently highlighted, and various device structures utilizing ZnTe are explored. ZnTe substrates are recently commercially available, and high quality homoepitaxial layers can be grown. On the other hand, the cost of the substrate could be a concern for the practical device application. In this study, Si and Al2O3 substrates were used since they are widely used for many kinds of device applications. The lattice mismatch between those substrate materials and ZnTe is above 10% and those mismatch strain should be carefully considered. ZnTe layers were nucleated on chemically treated substrate surfaces. (111), (110), (211) oriented Si substrates and (0001), (11-20), and (10-10) planes of Al2O3 were used. By taking the pole figure data and studying the crystal symmetry of the domain, detail information associated with the formation of domains in the layer was discussed. The pole figure analysis revealed that several kinds of (110) oriented ZnTe domains rotated 60 degrees each other were formed on (110) oriented Si surface. On the other hand, preferentially oriented single domain of (111) was confirmed for the layer grown on the (0001) plane of Al2O3. ZnTe layers grown on (10-10) plane Al2O3 exhibited a unique domain formation. Pole figure data combined with the conventional theta-2-theta measurement indicated that (211) oriented plane of ZnTe was a dominant domain formed on the (10-10) plane Al2O3. These crystallographic features would be related to the interface valency as well as the interfacial bond structure. X-ray pole figure method was a useful and powerful method to study the domain formation of the severely lattice mismatched structures. (C) 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

    DOI

  • Preparation of Nanoparticie Phosphor Films and its Application to Solar Cells

    Masakazu Kobayashi, Ayaka Yagi, Sayako Hamaguchi

    2012 12TH IEEE CONFERENCE ON NANOTECHNOLOGY (IEEE-NANO)    2012年

     概要を見る

    Ba2ZnS3:Mn (BZS), SrGa2S4:Eu, and BaAI(2)S(4):Eu nanoparticles phosphor materials were prepared by a break down method, namely the ball-milling method. Several-nanometer-size stoichiometric and dispersed nanoparticIes were achieved. Red color phosphor material, namely BZS, was sprayed on the glass substrate. Mn doped BZS absorbs ultra violet light and emits red light peaking at around 640nm. The transparent nanoparticle layer absorbed short wavelength light and converted to long wavelength light for the Si solar cell application.

    DOI

  • Growth of ZnMgTe/ZnTe waveguide structures on ZnTe (001) substrates by molecular beam epitaxy

    Y. Kumagai, S. Imada, T. Baba, M. Kobayashi

    JOURNAL OF CRYSTAL GROWTH   323 ( 1 ) 132 - 134  2011年05月

     概要を見る

    ZnMgTe/ZnTe/ZnMgTe layered structures were grown on (0 0 1) ZnTe substrates by molecular beam epitaxy. This structure was designed to apply to waveguides in various optoelectronic devices to reduce light loss. Since the lattice mismatch between ZnTe and ZnMgTe was not negligible, the critical layer thickness (CLT) was theoretically derived. Structures with varying Mg composition and layer thickness of ZnMgTe cladding layer were grown and examined for crystal quality with respect to theoretical data. The crystal quality was investigated by means of cross sectional transmission electron microscopy (TEM) and reciprocal space mapping (RSM). Optical confinements were observed by irradiating a laser beam from one end of the sample and monitoring the transmitted light from the other end. (C) 2011 Elsevier B.V. All rights reserved.

    DOI

  • ZnO coated nanoparticle phosphors

    Masakazu Kobayashi

    Materials Research Society Symposium Proceedings   1394   93 - 100  2011年

     概要を見る

    Conventional phosphor materials are doped ternary or quaternary compounds
    hence it would be difficult to prepare nanoparticles of those materials by build up methods. Ba2ZnS3:Mn (BZS), SrGa2S 4:Eu, and BaAl2S4:Eu nanoparticles were prepared by a break down method, namely the ball-milling method. Transmission electron microscopy (TEM) and TEM- energy-dispersive X-ray spectroscopy (EDX) measurements showed several-nanometer-size stoichiometric and dispersed nanoparticles were achieved. ZnO-coating was performed and the uniform coating layers were formed on the phosphor nanoparticles. The ZnO-coated nanoparticles exhibited an improved stability in Photoluminescence. Red color phosphor material, namely BZS, was ball-milled and sprayed on the glass substrate. Mn doped BZS absorbs ultra violet light and emits red light peaking at around 640nm. When the single crystal Si solar cell was placed under the transparent nanoparticle layer, short wavelength light was absorbed and converted to long wavelength light. © 2012 Materials Research Society.

    DOI

  • Growth and characterization of ZnMgTe/ZnTe layered structures grown by molecular beam epitaxy

    S. Imada, T. Baba, S. Sakurasawa, M. Kobayashi

    Physica Status Solidi (C) Current Topics in Solid State Physics   7 ( 6 ) 1473 - 1475  2010年

     概要を見る

    ZnMgTe/ZnTe layered structures were grown on ZnTe substrates by molecular beam epitaxy, and the crystal structures were characterized using X-ray diffraction methods. This structure would be the waveguide for various optoelectronic devices. Therefore, the crystal quality of this layered structure would be very crucial for the realization of high performance devices. ZnMgTe is lattice mismatched to ZnTe, and the increase of the ZnMgTe layer thickness or Mg mole fraction ratio would result in the crystal quality deterioration of the layered structure. The critical layer thickness (CLT) was theoretically derived, and various structures with various ZnMgTe layer thickness and Mg mole fraction were grown. The lattice mismatch strain relief and crystal quality of those samples were investigated by means of X-ray reciprocal space mapping (RSM) and cross sectional transmission electron microscopy (TEM). The dislocation formation and the lattice mismatch relaxation were confirmed for various samples and it was revealed that the calculated CLT values could be used as an appropriate guideline to design the dislocation free and high performance device structures. © 2010 Wiley-VCH Verlag GmbH &amp
    Co. KGaA.

    DOI

  • Growth and characterization of ZnMgTe/ZnTe layered structures grown by molecular beam epitaxy

    S. Imada, T. Baba, S. Sakurasawa, M. Kobayashi

    PHYSICA STATUS SOLIDI C: CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 7 NO 6   7 ( 6 ) 1473 - 1475  2010年  [査読有り]

     概要を見る

    ZnMgTe/ZnTe layered structures were grown on ZnTe substrates by molecular beam epitaxy, and the crystal structures were characterized using X-ray diffraction methods. This structure would be the waveguide for various optoelectronic devices. Therefore, the crystal quality of this layered structure would be very crucial for the realization of high performance devices. ZnMgTe is lattice mismatched to ZnTe, and the increase of the ZnMgTe layer thickness or Mg mole fraction ratio would result in the crystal quality deterioration of the layered structure. The critical layer thickness (CLT) was theoretically derived, and various structures with various ZnMgTe layer thickness and Mg mole fraction were grown. The lattice mismatch strain relief and crystal quality of those samples were investigated by means of X-ray reciprocal space mapping (RSM) and cross sectional transmission electron microscopy (TEM). The dislocation formation and the lattice mismatch relaxation were confirmed for various samples and it was revealed that the calculated CLT values could be used as an appropriate guideline to design the dislocation free and high performance device structures. (c) 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

    DOI

  • The effects of post-annealing on the crystallinity and the optical properties of SrGa<inf>2</inf>S<inf>4</inf>:Eu nanoparticles

    Savako Hamaguchi, Savako Hamaguchi, Takuma Yamamoto, Takuma Yamamoto, Masakazu Kobayashi

    IDW '09 - Proceedings of the 16th International Display Workshops   1   383 - 385  2009年12月

     概要を見る

    SrGa2S4:Eu has been recently widely studied. Annealing treatment in a vacuum and a H2S atmosphere is used for the improvement of the crystallinity and optical properties. H2S annealed nanoparticles showed better characterizations than vacuum annealed ones. Good samples in optical property indicate also good data in crystallinity.

  • Synthesis of Ternary Compound Sulfide Nanoparticles

    Sayako Hamaguchi, Takuma Yamamoto, Masakazu Kobayashi

    JAPANESE JOURNAL OF APPLIED PHYSICS   48 ( 4 )  2009年04月

     概要を見る

    Conventional phosphor materials are doped ternary or quaternary compounds; hence it would be difficult to prepare those nanoparticles by build up methods. Ba(2)ZnS(3):Mn, SrGa(2)S(4):Eu, and BaAl(2)S(4):Eu nanoparticles were prepared by a break down method, namely ball-milling method. Transmission electron microscopy (TEM), and TEM-energy-dispersive X-ray spectroscopy (EDX) measurements showed several-nanometer-size stoichiometric and dispersed nanoparticles were achieved. The annealing was performed after the milling for those particles to cure the mechanical damages. The annealing in a vacuum at around the calcination temperature of starting materials showed the cured photoluminescence (PL). ZnO-coating was performed and the uniform coating layer of the thickness about 10 nm was formed on the phosphor nanoparticles. The ZnO-coated nanoparticles exhibited an improved stability in PL. (C) 2009 The Japan Society of Applied Physics

    DOI

  • Preparation of ZnS:Mn2+ and Other Sulpher Compound Nanoparticles by Using a Ball-Milling Method

    S. Hamaguchi, S. Ishizaki, M. Kobayashi

    JOURNAL OF THE KOREAN PHYSICAL SOCIETY   53 ( 5 ) 3029 - 3032  2008年11月

     概要を見る

    ZnS:Mn2+ nanoparticles and other sulpher-based ternary compound nanoparticles were achieved using a ball-milling method. Several-nanometer-sized ZnS:Mn2+ nanoparticles were achieved by comminuting materials in a solvent. Both X-ray diffraction (XRD) and transmission electron microscopy (TEM) suggested that the particles had been milled down to the nanometer size. TEM-energy-dispersive X-ray spectroscopy (TEM-EDX) suggested that the stoichiometry of the starting powder was not affected by the ball-milling process. The orange-colored luminescence originating from Mn2+ was improved by reducing the particle size to several nanometers. Red, green and blue (RGB) colored phosphors were also studied using this technique. Ba2ZnS3:Mn (Red), SrGa2S4:Eu (Green), BaAl2S4:Eu (Blue) and phosphor materials with sizes of about several micrometers were comminuted to nanoparticles without affecting the crystal structure and the stoichiometry. Bright red, green and blue luminescence were confirmed from those nanoparticles.

  • Al and N co-doped ZnTe layers grown by MBE

    A. Ichiba, M. Kobayashi

    JOURNAL OF CRYSTAL GROWTH   301   285 - 288  2007年04月

     概要を見る

    The co-doping technique known as an effective method to circumvent the dopant compensation problem was applied for the molecular beam epitaxy (MBE) growth of homoepitaxial ZnTe layers. The co-doping concept is to introduce two oppositely polar atoms at the same time in a 2:1 ratio, forming metastable three-atom complexes located at adjacent crystal sites. Al donor and N acceptor were sandwiched between undoped ZnTe spacing layers. In order to reduce the beam intensity of the RF plasma excited nitrogen species, N-2 gas was diluted by Ar gas. From the low temperature PL spectra, the increase of the Al doping efficiency was confirmed for co-doped layers, especially co-doped using the diluted N-2 gas. (c) 2007 Elsevier B.V. All rights reserved.

    DOI

  • Mechanisms in the formation of high quality Schottky contacts to n-type ZnO

    M.W. Allen, C.H. Swartz, M. Henseler, R.J. Reeves, J.B. Metson, H. Von Wenckstern, M. Grundmann, S.A. Hafield, P.H. Jefferson, P.D.C. King, T.D. Veal, C. McConville, M. Kobayashi, S.M. Durbin

    Mat. Res. Soc. Symp. Proc.   955E  2007年  [査読有り]

  • Electroluminescence from single 3D GaN nanowire grown by self-catalytic molecular beam epitaxy

    C. E. Kendrick, C. E. Kendrick, R. Tilley, R. Tilley, M. Kobayashi, R. J. Reeves, R. J. Reeves, S. M. Durbin, S. M. Durbin

    Materials Research Society Symposium Proceedings   955   270 - 275  2006年12月

     概要を見る

    3-D branching GaN nanowires have been grown using the intermediate and Ga-rich growth regimes of plasma assisted molecular beam epitaxy. Evidence that the growth is due to an auto-catalytic VLS process is obtained through SEM images showing droplet termination heads, the composition of which is essentially pure Ga. TEM analysis revealed a defect free crystal structure, even in the trunk to branch junction. Cathodoluminescence from the trunk of the branching nanowires produced a strong luminescence feature at 3.44 eV, while a slight decrease in energy to 3.1 eV was observed at the interface between the nanowire and epilayer or kink site. No yellow luminescence was detected, further suggesting a defect free growth. Preliminary I-V measurements give mixed results, suggesting intrinsic n-type nanowires. © 2007 Materials Research Society.

  • Growth and optical property characterizations of ZnTe:(Al,N) layers using two co-doping techniques

    A. Icshba, J. Ueno, K. Ogura, S. Katsuta, M. Kobayashi

    Physica Status Solidi C: Conferences   3 ( 4 ) 789 - 792  2006年

     概要を見る

    In order to get around the high and activated n-doping levels for ZnTe, the co-doping technique known as effective method to overcome the dopant compensation was explored. The co-doping concept is to introduce two oppositely polar atoms at the same time in a 2:1 ratio, forming metastable three-atom complexes located at adjacent crystal sites. In this study, two types of deposition process were considered to place the co-dopants at the intended site, and the co-doped ZnTe:(Al, N) layers were grown on (001) oriented ZnTe substrates by molecular beam epitaxy. From the low temperature PL spectra, the increase of Al activation was confirmed by using co-doping sequences, and the activation of N dopant was also confirmed for one doping sequence even thought the doping level was maintained the same. © 2006 WILEY-VCH Verlag GmbH &amp
    Co. KGaA,.

    DOI

  • MBE growth of ZnSe/MgCdS and ZnCdS/MgCdS superlattices for UV-A sensors

    J. Ueno, K. Ogura, A. Ichiba, S. Katsuta, M. Kobayashi, K. Onomitsu, Y. Horikoshi

    Physica Status Solidi C: Conferences   3 ( 4 ) 1225 - 1228  2006年

     概要を見る

    ZnSe/MgCdS and ZnCdS/MgCdS superlattices were grown on semi insulating (001) oriented GaAs substrates by molecular beam epitaxy (MBE). The crystal quality and optical properties were examined for both superlattices. The observed photoluminescence (PL) peak intensity of ZnCdS/MgCdS was much stronger than that of ZnSe/MgCdS while ZnSe/MgCdS showed sharper luminescence line width. The PL peak energy position was compared with the theoretical value derived from the Kronig-Penny model. The degradation of crystal quality was observed by increasing Mg content in MgCdS layer and drastic PL property degradation was observed when the Mg content in the layer exceeded a certain value. Two superlattices were applied to the UV-A sensor of the metal-semiconductor-metal (MSM) configuration. Both photodetectors exhibited a high sensitivity in the UV-A region with a sharp cut-off in the visible wave-length region
    the ON-OFF ratio of sensor was about 103 for both structures. © 2006 WILEY-VCH Verlag GmbH &amp
    Co. KGaA,.

    DOI

  • Growth and optical property characterizations of ZnTe :(Al,N) layers using two co-doping techniques

    A Ichiba, J Ueno, K Ogura, S Katsuta, M Kobayashi

    PHYSICA STATUS SOLIDI C - CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 3, NO 4   3 ( 4 ) 789 - +  2006年  [査読有り]

     概要を見る

    In order to get around the high and activated n-doping levels for ZnTe, the co-doping technique known as effective method to overcome the dopant compensation was explored. The co-doping concept is to introduce two oppositely polar atoms at the same time in a 2:1 ratio, forming metastable three-atom complexes located at adjacent crystal sites. In this study, two types of deposition process were considered to place the co-dopants at the intended site, and the co-doped ZnTe:(Al, N) layers were grown on (00 1) oriented ZnTe substrates by molecular beam epitaxy. From the low temperature PL spectra, the increase of Al activation was confirmed by using co-doping sequences, and the activation of N dopant was also confirmed for one doping sequence even thought the doping level was maintained the same. (c) 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

    DOI

  • MBE growth of ZnSe/MgCdS and ZnCdS/MgCdS superlattices for UV-A sensors

    J Ueno, K Ogura, A Ichiba, S Katsuta, M Kobayashi, K Onomitsu, Horikoshi, V

    PHYSICA STATUS SOLIDI C - CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 3, NO 4   3 ( 4 ) 1225 - +  2006年  [査読有り]

     概要を見る

    ZnSe/MgCdS and ZnCdS/MgCdS superlattices were grown on semi insulating (001) oriented GaAs substrates by molecular beam epitaxy (MBE). The crystal quality and optical properties were examined for both superlattices. The observed photoluminescence (PL) peak intensity of ZnCdS/MgCdS was much stronger than that of ZnSc1MgCdS while ZnSe/MgCdS showed sharper luminescence line width. The PL peak energy position was compared with the theoretical value derived from the Kronig-Penny model. The degradation of crystal quality was observed by increasing Mg content in MgCdS layer and drastic PL property degradation was observed when the Mg content in the layer exceeded a certain value. Two superlattices were applied to the UV-A sensor of the metal-semiconductor-metal (MSM) configuration. Both photodetectors exhibited a high sensitivity in the UV-A region with a sharp cut-off in the visible wavelength region; the ON-OFF ratio of sensor was about 10(3) for both structures. (c) 2006 WILEY-VCH Veriag GmbH & Co. KGaA, Weinheim.

    DOI

  • Growth and UV-A sensor applications of MgCdS/ZnCdS superlattices

    M Kobayashi, J Ueno, M Enami, S Katsuta, A Ichiba, K Ogura, K Onomitsu, Y Horikoshi

    JOURNAL OF CRYSTAL GROWTH   278 ( 1-4 ) 273 - 277  2005年05月

     概要を見る

    The application of visible blind ultraviolet (UV)-A sensors was extensively studied for wide-bandgap II-VI compound epitaxial layers. The growth of ZnMgCdS quaternary alloys and MgCdS/ZnCdS short period superlattices were performed. and UV-A sensors were fabricated. The mole-fraction control of the tertiary alloy would be much easier than that of the quaternary alloy, and various structures with certain bandgap energy can be designed. The cross-sectional TEM observation has revealed that well-defined superlattice structures could be achieved. Low-temperature photoluminescence (PL) exhibited that the intense and sharp luminescence peak was observed from superlattice samples compared with quaternary alloy layers having the similar bandgap energy. The PL peak position could be controlled by changing the layer thickness as well as the mole-fraction ratio of the alloy. The PL peak energy positions agreed well with theoretically predicted values. After the film growth, Au electrodes were evaporated and photo-sensitivity was characterized for metal-semiconductor-metal configurations. Sharp cut-off profiles were observed for samples, and its position was consistent with the PL peak position. The ON-OFF ratio of the device was similar to that of the device using the quaternary alloy layers. (c) 2005 Elsevier B.V. All rights reserved.

    DOI

  • Fabrication of ZnO Coated ZnS:Mn2+ Nanoparticles

    Shinji Ishizaki, Yusuke Kusakari, Masakazu Kobayashi

    Mater. Res. Soc. Symp. Proc.   829   2221 - 2225  2005年

  • Preparation of SrS:Ce/ZnO core-shell nanoparticles using reverse micelle method

    Yusuke Kusakari, Shinji Ishizaki, Masakazu Kobayashi

    Mater. Res. Soc. Symp. Proc.   829   1021 - 1025  2005年

  • II-VI compound nano-particles prepared by a ball milling method

    M.Kobayashi, S. Ishizaki, M. Uenishi

    Proc. International conference on nanomaterials NANO2005   1   95 - 98  2005年

  • Spectroscopic studies of autofluorescence substances existing in human tissue: influences of lactic acid and porphyrins

    Y Ueda, M Kobayashi

    APPLIED OPTICS   43 ( 20 ) 3993 - 3998  2004年07月

     概要を見る

    The influence of lactic acid or porphyrins on the optical properties of tissue fluorophores is investigated by autofluorescence (AF) spectroscopy measurement with a GaN-based ultraviolet laser diode along with Fourier-transform IR (FTIR) spectroscopy measurement. As the lactic-acid concentration becomes dense, the AF peak intensity from elastin and desmosine solutions become wholly weak. A similar reduction in the AF intensity is observed for nicotinamide adenine dinucleotide (NADH) solutions. FTIR analysis indicates that the lactic acid causes the conformational change in elastin and the oxidation of NADH, which can be related to changes in the AF properties. The peak intensity of the tissue fluorophores also becomes weak when porphyrins are added, although the conformational change in each tissue fluorophore is not confirmed from FTIR analysis. Judging from the change in the scattering-light intensity of the excitation source, the observed change mainly originates from the absorption of the excitation source by porphyrins. (C) 2004 Optical Society of America.

    DOI

  • MBE growth of ZnMgCdS compounds on (001) GaAs for UV-A sensors

    M Enami, K Tsutsumi, F Hirose, S Katsuta, M Kobayashi

    11TH INTERNATIONAL CONFERENCE ON II-VI COMPOUNDS (II-VI 2003), PROCEEDINGS   1 ( 4 ) 1038 - 1041  2004年

     概要を見る

    Zincblende ZnMgCdS quaternary alloy layers were grown by molecular beam epitaxy. The ZnMgCdS alloy could lattice match to GaAs and could exhibit the band-gap energy of approximately 3 eV. Zn, Mg, and CdS were used as source materials. Incorporation of Mg was more effective compared with Zn in the alloy. Stabilizing the substrate temperature especially at the initial growth stage was crucial to obtain high quality layers. The epilayer was applied to the metal-semiconductor-metal photodetector, and the rejection rate above 10(3) have bean achieved. (C) 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  • ヒト気管支自家蛍光像における組織識別の検討

    鮫島冴映子, 小林正和

    電気学会論文誌C   124 ( 9 ) 1738 - 1743  2004年

    DOI

  • 分光画像解析法によるヒト気管支の自家蛍光測定

    鮫島 冴映子, 小林 正和, 渋谷 潔, 星野 英久, 千代 雅子, 藤沢 武彦

    日本レーザー医学会誌 = The Journal of Japan Society for Laser Medicine   24 ( 3 )  2003年09月

    CiNii

  • Molecular-beam epitaxial growth of ZnMgCdS layers and their application to UV-A photodetectors

    M Enami, K Tsutsumi, F Hirose, S Katsuta, M Kobayashi

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS   42 ( 9AB ) L1047 - L1049  2003年09月

     概要を見る

    Zincblende ZnMgCdS quaternary alloy layers were grown by molecular-beam epitaxy. The ZnMgCdS alloy lattice matched with GaAs and exhibited the band-gap energy of approximately 3 eV. Zn, Mg, and CDs were used as source materials. Cd was replaced by Zn or Mg, and the alloy composition was controlled when the growth temperature was set to approximately 210degreesC. Low-temperature photoluminescence showed dominant band-edge features indicating the high quality of the epilayer. The epilayer was applied to the metal-semiconductor-metal photodetector, and visible-blind UV sensing characteristics were observed.

    DOI

  • Low temperature treatment of the (001) ZnTe substrate surface with the assist of atomic hydrogen

    K Tsutsumi, H Terakado, M Enami, M Kobayashi

    JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B   21 ( 4 ) 1959 - 1962  2003年07月

     概要を見る

    Recent success in the fabrication of the bulk ZnTe has enabled the realization of large area single crystal substrates. The growth and application of ZnTe homoepitaxial layers by molecular beam epitaxy should involve the pretreatment of the substrate surface prior to the nucleation. An atomic hydrogen treatment was performed to remove the surface oxide of ZnTe. The oxide could be removed at around 100degreesC with the assist of the atomic hydrogen beam. The reconstructed surface could be achieved by annealing at around 230degreesC. The two dimensional nucleation was also confirmed. The homoepitaxial layer has shown such a high quality that interface, or defects could not be confirmed by the transmission electron microscopy. (C) 2003 American Vacuum Society.

    DOI

  • Spectroscopic imaging and the characterization of the autofluorescence properties of human bronchus tissues using UV laser diodes

    M Kobayashi, R Sawada, Y Ueda

    IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS   9 ( 2 ) 142 - 147  2003年03月

     概要を見る

    Ultraviolet laser diodes (UV-LD) were used for the excitation source of the autofluorescence (AF) measurements and spectroscopic imaging of the AF originated from the human bronchus was obtained. The AF spectra from the normal bronchus tissues were measured and the clear AF spectrum was obtained by using a short wavelength (400 nm) laser diode; the overlap of the AF signal and excitation source could be substantially eliminated. In order to study the origin of the AF intensity deterioration from the bronchus tissue due to the formation of the tumor tissues, the fluorescence spectrum was measured for various AF substances under various conditions. The blue AF signal of the elastin and NADH solutions which could not be easily studied by the conventional excitation light sources as well as the green AF became weak by adding the lactic acid. The AF spectrum was measured for 512 x 512 pixels and the intensity mapping as a function of the emission wavelength was obtained. Two-dimensional information of the AF signal intensity distribution for a certain wavelength component was measured. The feature originated from the region as small as about 100 mum could be recognized. The numerical calculation of the data was performed and the precise feature of the AF was revealed.

    DOI

  • Spectroscopic analysis of the autofluorescence from human bronchus using an ultraviolet laser diode

    M Kobayashi, K Shibuya, H Hoshino, T Fujisawa

    JOURNAL OF BIOMEDICAL OPTICS   7 ( 4 ) 603 - 608  2002年10月

     概要を見る

    A GaN based ultraviolet (UV) laser diode (LD) was used to study the autofluorescence (AF) spectrum of the normal and tumor human bronchial tissues under ex vivo conditions. The UV LD generates a coherent short wavelength (around 400 nm) light beam with an intensity of about a few watts. AF spectrum data can be obtained without interference by excitation light. A clear blue peak located at around 483 nm was observed along with a green peak at around 560 nm in the normal tissue. The peak intensities observed were very weak for the tumor tissues. The AF imaging and spectrum analysis were performed along with a histopathological study. The spatial distribution of the elastin in the bronchial tissue affected the intensity of the AF whereas the spectrum shape was not affected. Strong AF was observed from regions that include a high density of the elastin. Biopsy measurements were performed for ex vivo samples, and depth profiling of the elastin was studied along with variations of the AF spectrum. AF spectra excited by the UV LD for fluorescence materials including FAD, NADH, and elastin were measured. The spectrum shape of the elastin as well as of NADH was similar to that of normal bronchial tissues. (C) 2002 Society of Photo-Optical Instrumentation Engineers.

    DOI

  • Diffusion profiles of Se in bulk ZnTe

    M Kobayashi, H Terakado, R Sawada, A Arakawa, K Sato

    PHYSICA STATUS SOLIDI B-BASIC RESEARCH   229 ( 1 ) 265 - 268  2002年01月

     概要を見る

    Thermal diffusion of Se was performed in ZnTe substrates and the resulting material was characterized by TEM-EDS and X-ray reciprocal space mapping methods. ZnSe layers were formed on the surface of ZnTc substrates, and ZnSeTe ternary alloy layers with a certain alloy fraction region as well as a graded alloy fraction region were formed. The crystal quality of ZnSe and ZnSeTe region were affected by the diffusion conditions. High temperature diffusion and the use of H-2 carrier gas have resulted in the degradation of the bulk ZnTe region.

    DOI

  • 紫外線レーザダイオードによるヒト気管支の自家蛍光スペクトル測定

    小林正和, 渋谷潔, 星野英久, 藤澤武彦

    気管支学   Vol.24,No.5, 384-390  2002年

    DOI

  • P-60 紫外線レーザダイオードによるヒト気管支の自発蛍光スペクトル測定

    小林 正和, 渋谷 潔, 星野 英久, 藤澤 武彦

    気管支学   23 ( 3 )  2001年

    DOI CiNii

  • Autofluorescence spectroscopy analysis of the human bronchus using a UV laser diode

    M Kobayashi, K Shibuya, H Hoshino, T Fujisawa

    PROCEEDINGS OF THE 14TH WORLD CONGRESS OF THE INTERNATIONAL SOCIETY FOR LASER SURGERY AND MEDICINE   p125-129   125 - 129  2001年

  • Spectroscopy of self-assembled CdS quantum dots in ZnSe

    HL Zhou, AV Nurmikko, S Nakamura, K Kitamura, H Umeya, A Jia, M Kobayashi, A Yoshikawa, M Shimotomai, Y Kato

    JOURNAL OF APPLIED PHYSICS   88 ( 8 ) 4725 - 4728  2000年10月

     概要を見る

    Self-assembled nanocrystalline dots of CdS grown within a ZnSe host have been studied by steady state and transient optical spectroscopies. This material system features an unusually low density of the dots, into which the excitation transfer of excitons from the host has been identified. (C) 2000 American Institute of Physics. [S0021-8979(00)01921-6].

    DOI

  • Cubic InGaN/GaN double-heterostructure light emitting diodes grown on GaAs (001) substrates by MOVPE

    Y Taniyasu, K Suzuki, DH Lim, AW Jia, M Shimotomai, Y Kato, M Kobayashi, A Yoshikawa, K Takahashi

    PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE   180 ( 1 ) 241 - 246  2000年07月

     概要を見る

    Cubic (zinc-blende) InGaN/GaN double-heterostructure LEDs were fabricated on GaAs (001) substrates. The device performance and crystal quality were investigated. The emission wavelength was controlled by the In content in the cubic InGaN active layer. The violet-blue electroluminesence was observed around 435 nm with a FWHM of 55 nm from a cubic In0.07Ga0.93N/GaN DH LED. The forward voltage was 4.9 V at 20 mA and the reverse leakage current was 5 mA at -10 V. X-ray reciprocal space mapping measurement was performed to investigate the phase purity and strain in InGaN/GaN heterostructure. The mixing of the stable hexagonal phase in the cubic GaN was observed and the hexagonal phase content was about 10%. In-situ spectroscopic ellipsometry measurement showed that most of the mixed hexagonal domains were likely to be formed in the Mg-doped GaN layer. In addition, the anisotropic lattice relaxation occurred in the InGaN active layer. The elimination of the hexagonal phase inclusions plays an important role for the realization of high performance devices.

    DOI

  • Cross-sectional scanning tunneling microscopy characterization of cubic GaN epilayers grown on (001) GaAs

    T Kazama, F Yasunaga, Y Taniyasu, A Jia, Y Kato, M Kobayashi, A Yoshikawa, K Takahashi

    PHYSICA STATUS SOLIDI A-APPLIED RESEARCH   180 ( 1 ) 345 - 350  2000年07月

     概要を見る

    Atomic scale characterization of cleaved surfaces of cubic GaN (c-GaN) epilayers was established in real space. Using cross-sectional scanning tunneling microscopy (XSTM), c-GaN epilayers grown on GaAs (001) by low pressure MOVPE were investigated. The analysis of STM observations revealed that the atomic arrangement of the c-GaN (1 (1) over bar 0) surface depended on the crystal quality of the c-GaN epilayer. For high quality c-GaN regions, the STM image confirmed that the c-GaN (1 (1) over bar 0) surface was a 1 x 1 reconstruction in analogy to GaAs. On the other hand, for poor quality c-GaN regions, a structure different from the 1 x 1 reconstruction was observed, which was the disordered structure composed of atomic rows along the growth direction. Tn addition, stacking faults parallel to the c-GaN (111) plane, which gave rise to hexagonal GaN inclusions in the c-GaN epilayer, were characterized in real space.

    DOI

  • Cubic InGaN/GaN double-heterostructure light emitting diodes grown on GaAs (001) substrates by MOVPE

    Y. Taniyasu, K. Suzuki, D. H. Lim, A. W. Jia, M. Shimotomai, Y. Kato, M. Kobayashi, A. Yoshikawa, K. Takahashi

    Physica Status Solidi (A) Applied Research   180 ( 1 ) 241 - 246  2000年07月  [査読有り]

     概要を見る

    Cubic (zinc-blende) InGaN/GaN double-heterostructure LEDs were fabricated on GaAs (001) substrates. The device performance and crystal quality were investigated. The emission wavelength was controlled by the In content in the cubic InGaN active layer. The violet-blue electroluminescence was observed around 435 nm with a FWHM of 55 nm from a cubic In0.07Ga0.93N/GaN DH LED. The forward voltage was 4.9 V at 20 mA and the reverse leakage current was 5 mA at -10 V. X-ray reciprocal space mapping measurement was performed to investigate the phase purity and strain in InGaN/GaN heterostructure. The mixing of the stable hexagonal phase in the cubic GaN was observed and the hexagonal phase content was about 10%. In-situ spectroscopic ellipsometry measurement showed that most of the mixed hexagonal domains were likely to be formed in the Mg-doped GaN layer. In addition, the anisotropic lattice relaxation occurred in the InGaN active layer. The elimination of the hexagonal phase inclusions plays an important role for the realization of high performance devices.

    DOI

  • Self-assembled CdS quantum-dot structures grown on ZnSe and ZnSSe

    K Kitamura, H Umeya, A Jia, M Shimotomai, Y Kato, M Kobayashi, A Yoshikawa, K Takahashi

    JOURNAL OF CRYSTAL GROWTH   214   680 - 683  2000年06月

     概要を見る

    Self-assembled quantum dots (QDs) of CdS were grown on ZnSxSe1-x. Low-temperature photoluminescence (PL) properties of CdS QDs were studied and a blue shift was observed when the S composition in ZnSxSe1-x was increased. This shift is related to the band line-up between ZnSxSe1-x and CdS; the band line-up is type-II. Blue-light-emitting diode (LED) structures embedded in CdS QD layers in the pn junction of ZnSe or ZnSxSe1-x were fabricated. I-V characteristics were compared for two device structures. (C) 2000 Published by Elsevier Science B.V. All rights reserved.

    DOI

  • Growth of hexagonal ZnCdS on GaAs(111)B and (001) substrates by MBE

    H Umeya, K Kitamura, A Jia, M Shimotomai, Y Kato, M Kobayashi, A Yoshikawa, K Takahashi

    JOURNAL OF CRYSTAL GROWTH   214   192 - 196  2000年06月

     概要を見る

    The realization of wurtzite structure II-VI material would overcome the problem associated with the lifetime of the devices. ZnCdS epilayers were grown on GaAs(0 0 1) and(1 1 1)B substrates, and crystal structure was controlled, ZnCdS eyilayers grown on GaAs(0 0 1) substrates showed slight signs of the wurtzite phase. Phi (phi) scan of the X-ray diffraction was performed, and ZnCdS epilayers grown on GaAs(1 1 1)B substrates showed mixed crystal structures. The substrate temperature and the Cl doping would affect the volume ratio of the wurtzite structure. (C) 2000 Published by Elsevier Science B.V. All rights reserved.

    DOI

  • Growth of CdS self-organized quantum dots by molecular beam epitaxy and application to light emitting diode structures

    M Kobayashi, K Kitamura, H Umeya, AW Jia, A Yoshikawa, M Shimotomai, Y Kato, K Takahashi

    JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B   18 ( 3 ) 1684 - 1687  2000年05月

     概要を見る

    CdS quantum dots (QDs) were formed on ZnSe and ZnSxSe1-x. The nucleation process was monitored by reflection high energy electron diffraction, and it was suggested that QDs were formed without the wetting layer, The low temperature (13 K) photoluminescence (PL) measurement showed that the peak energy could be controlled by the amount of the CdS deposit. The PL peak energy covered most: of visible range, indicating that the band lineup between CdS QD and ZnSe (or ZnSxSe1-x) host would be type II. Bright green and blue light emitting diode (LED) structures were fabricated in which CdS QDs were embedded in pn junctions of ZnSe and ZnSxSe1-x. The control of QD size as well as the band gap of the host material enabled the luminescence peak wavelength of the LED to be varied. (C) 2000 American Vacuum Society.

    DOI

  • 第9回II-VI化合物国際会議報告

    安田 隆, 小林 正和

    應用物理   69 ( 4 )  2000年04月

    CiNii

  • Design of new UV/blue/green light emitters made of hexagonal-phase ZnMgCdOSSe mixed-crystal system fabricated on GaAs- and InP-(111) substrates

    A. Jia, T. Furushima, M. Kobayashi, Y. Kato, M. Shimotomai, A. Yoshikawa, K. Takahashi

    Journal of Crystal Growth   214   1085 - 1090  2000年

     概要を見る

    A new candidate for long lifetime short-wavelength light emitters made of hexagonal II-VI compounds has been proposed. In this paper, the results of theoretical design of ZnMgCdOSSe-based light emitters fabricated on (111) plane of GaAs and InP substrates is presented. The band lineups of CdZnS/ZnSSe and CdZnS/ZnMgS structures were estimated with Harrison's LCAO theory. Further, as for the first step of an experimental investigation on the growth of high phase-quality hexagonal II-VI compounds, growth of CdZnS epilayers were examined on GaAs(111) substrate. The epilayers were characterized by high-resolution X-ray diffraction reciprocal space and pole figure measurements. In this study, the optimum growth temperature was 300°C for hexagonal phase CdZnS, and the inclusion of cubic phase CdZnS drastically decreased with increasing Cd content at 300°C.

    DOI

  • Surface, and microstructural characterization of homoepitaxial silicon grown by pulsed laser deposition

    JS Pelt, R Magana, ME Ramsey, E Poindexter, S Atwell, JP Zheng, SM Durbin

    NEW METHODS, MECHANISMS AND MODELS OF VAPOR DEPOSITION   616   75 - 80  2000年

     概要を見る

    There is a great deal of interest in thin firm deposition techniques which can achieve good crystal quality at low substrate temperatures. Pulsed laser deposition (PLD), well-known as a reliable technique for fabrication of high critical temperature superconductor thin films, has a number of characteristics which may make it. suitable for such applications. In particular, PLD is characterized by a relatively large average species energy, which can be controlled by the laser fluence at the target. This paper describes the growth of silicon on silicon films using PLD over substrate temperatures between 500 and 700 degreesC, and in-situ characterization using reflection high-energy electron diffraction (RHEED). Transmission electron microscopy confirms the growth of single crystal oriented films, and atomic force microscopy indicates smooth films with an rms surface roughness of less than 2 Angstrom.

    DOI

  • Influence on the inclusion of h-GaN domain of the mosaicity in c-GaN epilayer grown on (001) GaAs substrate by rf-MBE

    H Hayashi, A Hayashida, AW Jia, M Kobayashi, A Yoshikawa, K Takahashi

    COMPOUND SEMICONDUCTORS 1999   ( 166 ) 475 - 478  2000年  [査読有り]

     概要を見る

    Inclusion of hexagonal GaN (h-GaN) phase domain associated with the mosaicity of the cubic GaN (c-GaN) phase have been investigated for c-GaN epilayer grown on (001) GaAs by rf-MBE. In the c-GaN epilayer with 10 % h-GaN phase, two diffraction peaks near (002) c-GaN were observed in the X-ray reciprocal space Mapping. One is the strong and narrow peak arising from the pure c-GaN phase and the other is the weak and broad peak arising from the secondary c-GaN phase with mosaicity. The broad peak showed its peak shift from the calculated diffraction angle, i.e., the tilt of c-GaN [001] axis is attributed to the secondary phase c-GaN domain. The diffraction peak for (10-11) h-GaN also showed its peak shift from the calculated diffraction angle. Therefore, it is considered that the h-GaN phase domain was preferentially included in the secondary phase c-GaN domain.

  • Luminescence properties of CdS quantum dots on ZnSe

    M. Kobayashi

    Journal of Vacuum Science and Technology B: Microelectronics and Nanometer Structures   17   2005 - 2008  1999年12月

     概要を見る

    The luminescence properties of self-assembled CdS quantum dots (QDs) were studied. CdS QD structures formed on ZnSe buffer layers without capping layers showed intense photoluminescence (PL). The PL peak position could be controlled by changing the amount of CdS deposited. Introduction of the capping layer enhanced the PL intensity. The buffer layer material selected also affected the luminescence properties of the CdS QDs, and brighter PL with the higher transition energy was observed by replacing the ZnSe buffer layer with ZnSSe. A light emitting diode structure based on CdS QDs sandwiched in the pn junction of ZnSe was fabricated and bright blue or green luminescence from current injection was observed at 77 K as well as at room temperature. © 1999 American Vacuum Society.

    DOI

  • Structural defects of cubic InGaN/GaN heterostructure grown on GaAs(001) substrate by MOVPE

    Y Taniyasu, Y Watanabe, DH Lim, AW Jia, M Shimotomai, Y Kato, M Kobayashi, A Yoshikawa, K Takahashi

    PHYSICA STATUS SOLIDI A-APPLIED RESEARCH   176 ( 1 ) 397 - 400  1999年11月

     概要を見る

    Cubic InGaN/GaN heterostructures were grown on GaAs(001) substrates by MOVPE. X-ray reciprocal space mapping (RSM) measurements were used to investigate the structural defects. It was revealed that the cubic InGaN layers contained high density stacking faults parallel to the cubic InGaN {111} planes, and hexagonal domains with their c-axes parallel to the cubic InGaN [111] directions. The hexagonal domains were preferentially oriented to the-cubic InGaN [111]A directions rather than the [111] B directions. It was clarified that the cubic InGaN layer was anisotropically strained; and this would be originated from the anisotropic mixing of the hexagonal phase in the cubic InGaN epilayers.

    DOI

  • Homoepitaxy of ZnSe on the citric acid etched (100)ZnSe surface

    M Kobayashi, K Wakao, S Nakamura, A Jia, A Yoshikawa, M Shimotomai, Y Kato, K Takahashi

    JOURNAL OF CRYSTAL GROWTH   201   474 - 476  1999年05月

     概要を見る

    ZnSe substrate surfaces were treated by the citric acid-based etchant. Homoepitaxial layers of ZnSe grown by MBE using this etching treatment showed excellent film qualities based on X-ray rocking curve and transmission electron microscopy observations. The electrical properties of the n-ZnSe/n-ZnSe interface prepared using this etchant was studied, and the C-V measurement showed that a good electrical interface was formed. (C) 1999 Elsevier Science B.V. All rights reserved.

    DOI

  • Origin of the tilt of crystalline axis influenced by the N-beam incidence direction in rf-MBE of cubic GaN epilayer on (001) GaAs

    H. Hayashi, A. Hayashida, A. W. Jia, M. Kobayashi, M. Shimotomai, Y. Kato, A. Yoshikawa, K. Takahashi

    Physica Status Solidi (B) Basic Research   216 ( 1 ) 241 - 245  1999年

     概要を見る

    We found that the direction of the [001] axis of the c-GaN epilayer grown on (001) GaAs was slightly tilted towards the direction of the N-beam during the epitaxial growth by rf-MBE, where the N-beam was incident obliquely to the surface normal. When the tilt of the c-GaN [001] axis was observed, the typical X-ray rocking FWHM value for (002) c-GaN was about 60 arcmin. This indicates that the large mosaicity is related to the tilt of the c-GaN [001] axis. Because the tilt is easily observed for the c-GaN epilayers grown at high growth rate, this implies that the large amount of N species on the growing surface is the origin of the tilt of c-GaN [001] axis. As for the inclusion of the h-GaN phase domain, we found that the peak shifts for the (1011) h-GaN planes occurred in accordance with the peak shift of (002) c-GaN in reciprocal space mappings.

    DOI

  • Spectroscopy of self-assembled quantum dots in ZnSe

    Hailong Zhou, A. V. Nurmikko, M. Kobayashi, A. Yoshikawa

    IQEC, International Quantum Electronics Conference Proceedings     15 - 16  1999年01月

     概要を見る

    Quantum dots are spectroscopically investigated based on CdS and ZnSe heteroepitaxy by molecular beam methods. The lattice mismatch between CdSe and ZnSe is about 3%, a relative modest value. Another unusual characteristic is that MBE grown CdS layers show a metastable crystallographic feature.

  • X-ray diffraction reciprocal space and pole figure characterization of cubic GaN epitaxial layers grown on (0 0 1) GaAs by molecular beam epitaxy

    Zhixin Qin, Masakazu Kobayashi, Akihiko Yoshikavva

    Journal of Materials Science: Materials in Electronics   10 ( 3 ) 199 - 202  1999年

     概要を見る

    X-ray diffraction reciprocal space maps and pole figures were used to analyze the cubic GaN epitaxial layers grown on (0 0 1) GaAs by r.f. plasma source MBE
    the presence of hexagonal phase in cubic GaN layers was detected by high resolution x-ray analysis and the relationships among various crystal axes of cubic and hexagonal phase GaN were analyzed with respect to V/III source-supply ratio. As for the growth conditions of the epitaxial layers, the V/III ratio was found to drastically affect the quality of the layers. High-temperature growth under near-stoichiometric conditions was necessary to obtain high quality epitaxial layers. It was found that inclusion of the hexagonal phase in the cubic GaN layers could be less than 0.4%, though previously reported typical c-GaN epitaxial layers included as much as 10-20% hexagonal phase GaN. On the basis of the measurements and analyses of reciprocal space maps and pole figures, it was revealed that the orientation of crystal axes of the hexagonal phase was unique in the present GaN epitaxial layers and they were different from those of previously reported c-GaN epitaxial layers.

    DOI

  • Bright electroluminescence from CdS quantum dot LED structures

    S Nakamura, K Kitamura, H Umeya, A Jia, M Kobayashi, A Yoshikawa, M Shimotomai, S Nakamura, K Takahashi

    ELECTRONICS LETTERS   34 ( 25 ) 2435 - 2436  1998年12月

     概要を見る

    Self-assembled quantum dots of CdS were introduced into the pn junction of ZnSe. Bright luminescence was observed at 77 K and room temperature. The peak wavelength can be tuned by altering the dimensions of the quantum dot structure.

    DOI

  • 原子状水素によるGaAs(001)基板表面の超平坦化と純立方晶GaNの分子線エピタキシャル成長

    泰 志新, 賈 岸偉, 小林 正和, 吉川 明彦

    真空   41 ( 11 ) 950 - 954  1998年11月

     概要を見る

    A two-step atomic-hydrogen (atomic-H) treatment of GaAs substrate was investigated; this includes low-temperature cleaning and high-temperature smoothening of GaAs (001) substrate surface. It was found that atomically flat GaAs surface with one monolayer-height steps and ragged step edges could be obtained by the atomic-H treatment at high temperatures. Further, growth of high quality cubic GaN (c-GaN) on atomic-H treated GaAs (001) was examined by rf plasma-assisted MBE. The c-GaN epilayers were characterized by high resolution X-ray diffraction analysis. The results show that the FWHM of the X-ray rocking curve for the (002) c-GaN was as small as 70-90 arcsec and the inclusion of hexagonal GaN phase was about 0.4% (or below). This indicates that the atomic-H irradiation treatment of the GaAs substrate was an efficient method obtaining High quality c-GaN.

    DOI CiNii

  • 2-4族化合物半導体の最新動向 (特集 化合物半導体の可能性を再点検する)

    小林 正和

    電子材料   37 ( 11 ) 41 - 45  1998年11月

    CiNii

  • Atomically-Flat GaAs(001) Surface Achieved by Atomic-Hydrogen Treatment and MBE Growth of Purely Cubic-Phase GaN

    Zhixin Qin, Anwei Jia, Masakazu Kobayashi, Akihiko Yoshikawa

    Shinku/Journal of the Vacuum Society of Japan   41   950 - 954  1998年11月

     概要を見る

    A two-step atomic-hydrogen (atomic-H) treatment of GaAs substrate was investigated; this includes low-temperature cleaning and high-temperature smoothening of GaAs(001) substrate surface. It was found that atomically flat GaAs surface with one monolayer-height steps and ragged step edges could be obtained by the atomic-H treatment at high temperatures. Further, growth of high quality cubic GaN (c-GaN) on atomic-H treated GaAs(001) was examined by rf plasma-assisted MBE. The c-GaN epilayers were characterized by high resolution X-ray diffraction analysis. The results show that the FWHM of the X-ray rocking curve for the (002) c-GaN was as small as 70-90 arcsec and the inclusion of hexagonal GaN phase was about 0.4% (or below). This indicates that the atomic-H irradiation treatment of the GaAs substrate was an efficient method obtaining High quality c-GaN.

    DOI

  • Citric acid etching of ZnSe surface and application to the homoepitaxy by molecular beam epitaxy

    K Wakao, S Nakamura, AW Jia, M Kobayashi, A Yoshikawa, M Shimotomai, Y Kato, K Takahashi

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS   37 ( 6B ) L749 - L751  1998年06月  [査読有り]

     概要を見る

    A citric acid based etchant was applied to ZnSe. The etching rate could be controlled by adjusting the mixture ratio as well as the etchant temperature. By choosing an appropriate mixture ratio and temperature, a surface smoothness of ZnSe after citric acid etching was as good as those of molecular beam epitaxy (MBE) grown ZnSe epilayers. Homoepitaxial layers of ZnSe grown by MBE using this etching treatment showed excellent film qualities based on X-ray rocking curve, cross-sectional transmission electron microscopy, and low-temperature photoluminescence measurements.

    DOI

  • Atomically flat (001)GaAs surface prepared by two-step atomic-hydrogen treatment and its application to heteroepitaxy of GaN

    H Nagano, ZX Qin, AW Jia, Y Kato, M Kobayashi, A Yoshikawa, K Takahashi

    JOURNAL OF CRYSTAL GROWTH   189   265 - 269  1998年06月

     概要を見る

    Substrate surface treatment techniques and growth conditions are the key of growing high-quality cubic GaN (c-GaN) epitaxial layers on (0 0 1) GaAs substrates. An atomically flat (0 0 1) GaAs substrate surface can be obtained by a two-step atomic hydrogen (atomic-H) irradiation technique. The typical surface of the substrate treated by the atomic-H consists of narrow terraces of one monolayer step height with acute-angle polygonal structures. The X-ray rocking curve FWHM of GaN (0 0 2) grown on the atomic-H treated substrate is less than 90 arcsec. It is shown that high-density monolayer steps and kinks at the surface terrace edge would be preferable for the uniform nucleation of the c-GaN buffer layer. (C) 1998 Elsevier Science B.V. All rights reserved.

    DOI

  • Spectroscopic ellipsometry study on initial growth stages of GaN films on GaAs(001) in low-pressure MOVPE

    Y Taniyasu, R Ito, N Shimoyama, M Kurihara, A Jia, Y Kato, M Kobayashi, A Yoshikawa, K Takahashi

    JOURNAL OF CRYSTAL GROWTH   189   305 - 309  1998年06月  [査読有り]

     概要を見る

    Initial growth stages of cubic GaN (c-GaN) films on GaAs(0 0 1) in low-pressure MOVPE were studied by spectroscopic ellipsometry. The GaN buffer layer was deposited at 500 degrees C and was then annealed at 700 degrees C with H-2/nonomethylhydrazine (MMHy) ambient. Spectroscopic ellipsometry revealed that the buffer layer thickness was increased and the surface was roughened during the annealing process. The change of surface morphology was also confirmed by the atomic force microscopy measurement, These observations would be associated with the nitridation of the GaAs substrate by the ambient MMHy and re-crystallization of the GaN buffer layer. Spectroscopic ellipsometry is a helpful technique to study the initial growth stages of GaN films on GaAs substrates. (C) 1998 Elsevier Science B.V. All rights reserved.

    DOI

  • High-resolution X-ray diffraction analysis of cubic GaN grown on (001)GaAs by RF-radical source molecular beam epitaxy

    ZX Qin, H Nagano, Y Sugure, AW Jia, M Kobayashi, Y Kato, A Yoshikawa, K Takahashi

    JOURNAL OF CRYSTAL GROWTH   189   425 - 429  1998年06月

     概要を見る

    Cubic GaN epilayers were grown on atomic hydrogen treated (0 0 1)GaAs substrates by RF-radical source molecular beam epitaxy. The crystalline quality was characterized by a high-resolution X-ray diffractometer. It was found that high-quality c-GaN can be grown at temperatures above 680 degrees C; the FWHM of (0 0 2)GaN rocking curve was as small as 80-90 arcsec. In order to further precisely investigate how and to what extent the h-GaN phase is included in the c-GaN layer, the X-ray reciprocal space maps were measured for the X-ray beams incident along both [1 1 0] and [1 (1) over bar 0] azimuths. It was found that the stacking faults exist predominantly on {1 1 1}A planes. The inclusion of h-GaN was estimated by comparing the integrated XRD intensities for h-GaN {1 0 (1) over bar 1} and c-GaN(0 0 2) planes. It was found that the inclusion of h-GaN phase drastically decreased with increasing growth temperature above 680 degrees C to reach about 4 x 10(-3) (or below) at temperatures of 710-740 degrees C. (C) 1998 Elsevier Science B.V. All rights reserved.

    DOI

  • Molecular beam epitaxy of CdS self-assembled quantum dots on ZnSe

    M Kobayashi, S Nakamura, K Wakao, A Yoshikawa, K Takahashi

    JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B   16 ( 3 ) 1316 - 1320  1998年05月

     概要を見る

    CdS quantum dot (QD) structures were grown by molecular beam epitaxy on (001) ZnSe. Circular QDs were observed from the sample, grown at 220 degrees C, whereas rectangular QDs were observed from the sample grown at 280 degrees C. The difference of the dot shape may be related to the metastable nature of CdS since CdS thin films grown at 220 degrees C show zincblende structures and thin films grown at 280 degrees C show wurtzite structures. The PL peak position and linewidth were strongly affected by the growth condition of QDs; QD samples with a thicker CdS deposition showed redshifts of the peak position along with the narrowing of the linewidth. (C) 1998 American Vacuum Society.

    DOI

  • High-resolution X-ray diffraction analysis of "device-quality" cubic GaN grown on (001)GaAs substrate prepared by atomic-hydrogen treatment at "high temperatures"

    A Yoshikawa, ZX Qin, H Nagano, Y Sugure, AW Jia, M Kobayashi, M Shimotomai, Y Kato, K Takahashi

    NITRIDE SEMICONDUCTORS   482   465 - 470  1998年

     概要を見る

    Cubic GaN (c-GaN) layers were grown by rf-plasma source MBE on (001) GaAs prepared by atomic-hydrogen treatment at "high temperatures", and the structural properties of the epilayers were investigated by the high-resolution X-ray rocking curve and the reciprocal space mapping measurements. The growth temperature was varied from 620 to 740 degrees C. It was found that single domain "device-quality" c-GaN layers could be grown for the first time; the FWHM of the X-ray rocking curves for the (002) c-GaN could be as small as 70-90 arcsec and the inclusion of h-GaN phase in the c-GaN epilayers grown at temperatures above 680 degrees C could be less than 4x10(3).

  • Effect of atomic-hydrogen treatment of (001) GaAs substrate at "high temperatures" on RF plasma-assisted molecular beam epitaxy of cubic GaN

    A Yoshikawa, H Nagano, ZX Qin, Y Sugure, AW Jia, M Kobayashi, M Shimotomai, Y Kato

    NITRIDE SEMICONDUCTORS   482   227 - 232  1998年

     概要を見る

    Growth of high quality c-GaN on atomic-II treated (001) GaAs was examined by rf plasma-assisted MBE. First the initial growth stages (atomic-H treatment of GaAs, nitridation/deposition of a thin GaN buffer layer, the post deposition annealing of the buffer layer, and epitaxy of c-GaN) were studied by RHEED and AFM observations. It was found that atomically flat GaAs surface with one monolayer-height steps and ragged step edges could be obtained by the atomic-II treatment at high temperatures. It was found that the atomic-II treated GaAs surface was preferable to grow high quality c-GaN; the FWHM of the X-ray rocking curve for the (002) c-GaN was as small as 70 - 90 arcsec.

  • MBE growth and characterization of ZnS1-xTex and Zn1-yMgyS1-xTex alloys

    M. Kobayashi, C. Setiagung, K. Wakao, S. Nakamura, A. Yoshikawa, K. Takahashi

    Journal of Crystal Growth   184-185   66 - 69  1998年

     概要を見る

    ZnS1-xTex and Zn1-yMgyS1-xTex epilayers were grown on (1 0 0)GaAs by MBE. Ternary and quaternary alloys can be lattice matched to GaAs by adjusting the composition of the group VI and group II elements. Zincblende structure layers were grown and p-doping was achieved. A fairly good ohmic contact profile was obtained between gold and the alloy. By using the Au/p-ZnS1-xTex contacting layer, ohmic contact was obtained to p-ZnSe. p-Zn1-yMgyS1-xTex layers were applied to cladding layers of the LED, and bright luminescence was observed. © 1998 Elsevier Science B. V. All rights reserved.

    DOI

  • MBE growth of device-quality cubic GaN on atomically flat (001)GaAs prepared by atomic-hydrogen treatment at high-temperatures

    A Yoshikawa, Z Qin, H Nagano, Y Sugure, A Jia, M Kobayashi, Y Kato, K Takahashi

    SILICON CARBIDE, III-NITRIDES AND RELATED MATERIALS, PTS 1 AND 2   264-2   1221 - 1224  1998年

     概要を見る

    Growth of high-quality and/or "purely cubic" GaN layers on (001) GaAs has been investigated by an rf-radical source MBE:paying particular attention to the effect of surface cleaning: and smoothing on the structural properties of the GaN epilayers. Device-quality c-GaN layers can be grown on the (001) GaAs treated by atomic hydrogen at high temperatures; the FWHM of X-ray rocking curve for the c-GaN (002) plane is as small as 80-90 arcsec and also the inclusion of the hexagonal phase GaN in the epilayer can be less than 4x10(-3).

  • Study on the initial growth stage of device-quality cubic GaN on (001) GaAs by RHEED and AFM: the nitridation and buffer-layer deposition processes in MBE

    H Hayashi, A Hayashida, Y Sugure, ZX Qin, AW Jia, M Kobayashi, M Shimotomai, Y Kato, A Yoshikawa, K Takahashi

    BLUE LASER AND LIGHT EMITTING DIODES II     508 - 511  1998年  [査読有り]

     概要を見る

    Growth of high-quality cubic GaN (c-GaN) layers on GaAs has been investigated by an rf-radical source MBE in terms of nitridation of the substrate and buffer layer deposition at initial growth stage. The nitridation of the (001) GaAs surface at 620 degrees C resulted in the formation of c-GaN with rough surface. In order to obtain flat surface of c-GaN, we have examined the nitridation process at low temperature. It was found that the nitridation of GaAs surface at 500 degrees C was suitable, because the reaction of Ga with N was slow enough to form c-GaN uniformly and the surface was kept flat even after the nitridation.

  • A study on initial nucleation using an ultra thin amorphous buffer layer for the growth of GaN on Al2O3(0001) by molecular beam epitaxy

    R Kimura, K Takahashi, A Jia, M Kobayashi, A Yoshikawa

    BLUE LASER AND LIGHT EMITTING DIODES II     492 - 495  1998年  [査読有り]

     概要を見る

    Detailed investigation of Al2O3 pre-treatment and initial nucleation process were performed in order to grow a high quality GaN thin film on Al2O3(0001) by molecular beam epitaxy. The atomic step of an Al2O3 surface was successfully obtained by chemical etching using H3PO4:H2SO4. It was found that a very thin (26 Angstrom) amorphous buffer layer of atomic steps could form a uniform nucleation which consists of minute nuclei (RMS = 0.17 nm). The epilayer, which grew on this nucleation layer showed a significant improvement in crystal quality. Band edge emission (357 nm/FWHM = 22meV) without any deep emission band was observed with low temperature photoluminescence and the FWHM of the X-ray rocking curve was 20 arcmin.

  • In-situ monitoring of the surface kinetics of the cubic GaN films in MOVPE using spectroscopic ellipsometry

    Y Taniyasu, E Sato, H Sato, N Shimoyama, A Jia, M Shimotomai, Y Kato, M Kobayashi, A Yoshikawa, K Takahashi

    BLUE LASER AND LIGHT EMITTING DIODES II     74 - 77  1998年  [査読有り]

     概要を見る

    Spectroscopic ellipsometry (SE) was used to study the surface stoichiometry of the cubic GaN layers during MOVPE growth. The relationship between the surface conditions and the crystal quality of the cubic GaN layers was clarified. The signal change corresponding to the variation of the surface stoichiometry was observed; the N coverage of the cubic GaN surface was drastically decreased when the V/III molar ratio was below 20 at 800 degrees C. The crystal quality of the cubic GaN layers was characterized by using X-ray reciprocal space mapping. The growth under the Ca-rich condition was suitable to improve the crystal quality of the cubic GaN. The surface stoichiometry of the cubic GaN layers during MOVPE growth strongly affected the crystal quality of GaN epilayers and the precise control of the surface stoichiometry is important to minimize the inclusion of the hexagonal phase.

  • Effect of V/III source-supply ratio on the crystalline-structure quality of the cubic GaN epilayer grown on (001) GaAs by MBE

    ZX Qin, AW Jia, M Kobayashi, M Shimotomai, Y Kato, A Yoshikawa, K Takahashi

    BLUE LASER AND LIGHT EMITTING DIODES II     504 - 507  1998年  [査読有り]

     概要を見る

    The cubic GaN epilayers were grown on (001) GaAs under different V/III source-supply ratio by rf-radical source MBE. The inclusion of hexagonal phase in cubic GaN layers was detected by high resolution X-ray analysis and the relationships among various crystal axes of cubic and hexagonal phase GaN were analyzed by X-ray diffraction reciprocal space mappings and pole figures. The V/III ratio was found to drastically affect the quality of the layer. High-temperature growth under near-stoichiometric condition was necessary to obtain high quality epilayers. It was found that the inclusion of hexagonal phase in the cubic GaN layers could be less than 0.4 %. The measurements and analyses of reciprocal space maps and pole figures revealed that the orientation of crystal axes of the hexagonal phase was quite unique in the present GaN epilayers and they were different from those of previously reported c-GaN epilayers.

  • Atomically flat GaAs(001) surfaces obtained by high-temperature treatment with atomic hydrogen irradiation

    K Yamaguchi, ZX Qin, H Nagano, M Kobayashi, A Yoshikawa, K Takahashi

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS & EXPRESS LETTERS   36 ( 10B ) L1367 - L1369  1997年10月

     概要を見る

    An atomically flat GaAs(001) surface can be obtained by a two-step atomic hydrogen (atomic-H) irradiation technique. This method includes low-temperature cleaning and high-temperature smoothening of the GaAs substrate surface. The reflection high energy electron diffraction (RHEED) and AFM study showed that a wide terrace with a 1 monolayer step height was observed when a GaAs(001) surface was cleaned at 400 degrees C and smoothened at 540 degrees C with atomic-H irradiation. The irradiation of atomic-H during the high temperature process maintained a certain surface stoichiometry, and resulted in an atomically flat substrate surface. This technique is useful for heterovalent epitaxy systems involving a single chamber growth system.

    DOI

  • 原子状水素を用いて表面処理を行ったGaAs(001)基板上への高品質立方晶GaNのMBE成長

    永野 元, 秦 志新, 賈 岸偉, 加藤 嘉則, 小林 正和, 吉川 明彦

    電子情報通信学会技術研究報告. LQE, レーザ・量子エレクトロニクス   97 ( 100 ) 37 - 42  1997年06月

     概要を見る

    六方晶構造が安定であるGaN(h-GaN)をGaAs(001)や3C-SiC(001)等の立方晶構造の基板上に成長することで, 立方晶構造のGaN (c-GaN)を作製できる. c-GaNはLDデバイス化に際し共振器や電極の形成がh-GaNに比べて容易であると考えられている. しかし基板表面や成長表面に凹凸が存在すると, c-GaN中には元々安定であるh-GaNが混在しやすく高品質なc-GaNを得るのが難しい. そこで, 本研究では原子状水素(H^*)を用いて清浄化及び平坦化を行ったGaAs基板上に, rf-MBE法によりGaNの成長を行った. その結果, GaN(002)X線ロッキングカープにおいてFWHMが90arcsecであるような, 高品質のc-GaNを得ることができた. これは, H^*により処理したGaAs基板表面が, 分子層オーダーで平坦でありそのステップ端に多数のキンクを持つため, 成長初期において成長核が一様, 高密度に生成し, GaNが一様に成長したためと考えられる.

    CiNii

  • これからの光ディスク技術(2)情報密度を高める青色レ-ザ-

    Gunshor Robert L, Nurmikko Arto V, 小林 正和

    日経サイエンス   26 ( 9 ) 34 - 38  1996年09月

    CiNii

  • Phase instability of n-CdS grown by molecular-beam epitaxy

    T Yamada, C Setiagung, AW Jia, M Kobayashi, A Yoshikawa

    JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B   14 ( 3 ) 2371 - 2373  1996年05月

     概要を見る

    The metastable nature of molecular-beam epitaxy grown CdS layers was studied. Undoped CdS layers were grown on (100) GaAs substrates/(100) ZnSe buffer layers, and crystal structures were characterized by x-ray diffraction and transmission electron microscopy. Undoped films showed both zincblende and wurtzite structures depending on the growth condition; higher substrate temperatures and smaller VI/VII beam intensity ratios preferentially form wurtzite structures. The Ga doping significantly affected the crystal structure and Ga doped CdS layers preferentially formed wurtzite structures. Thermal instability of the CdS him was observed through various ex situ annealing experiments. The wurtzite structure phase was developed from the zincblende structure CdS layers by thermal annealing where the annealing temperature was lower than the growth temperature. (C) 1996 American Vacuum Society.

    DOI

  • Improved contacts to p-type ZnSe using a ZnTe/Ga2Se3 contact layer and related p-n junction diode structures

    T Yoshida, M Kobayashi, A Yoshikawa

    BLUE LASER AND LIGHT EMITTING DIODES     461 - 464  1996年  [査読有り]

  • Reduction of p-ZnTe/p-ZnSe valence band discontinuity by a Ga2Se3 interfacial layer

    T. Yoshida, T. Nagatake, M. Kobayashi, A. Yoshikawa

    Journal of Crystal Growth   159 ( 1-4 ) 750 - 753  1996年

     概要を見る

    The defect zincblende structure Ga2Se3 was inserted at the interface of ZnSe and ZnTe so that the valence band discontinuity (ΔEv) could be modified. The valence band discontinuity was determined from the capacitance-voltage (C-V) measurement technique. The measured ΔEv depended on the thickness of the Ga2Se3 interfacial layer. The discontinuity became negligible when the thickness of the interfacial layer was about 4 Å. The current-voltage (I-V) characteristics for the Au/p-ZnTe/Ga2Se3/p-ZnSe/p-GaAs structure exhibited a perfectly linear plot when the thickness of the interfacial layer was about 8 Å. These results suggest that the valence band discontinuity between ZnTe and ZnSe can be reduced by introducing the Ga2Se3 interfacial layer.

    DOI

  • Real time monitoring of growth and p-type doping processes in MOVPE of ZnSe

    M. Miyachi, Y. Ohira, S. Komatsu, M. Kurihara, N. Shimoyama, M. Kobayashi, Y. Kato, A. Yoshikawa

    Journal of Crystal Growth   159 ( 1-4 ) 261 - 265  1996年

     概要を見る

    Growth and p-type doping processes in MOVPE of ZnSe have been studied by optical probing methods called RD (reflectance difference) and SPI (surface photo-interference). As for the dopant source, tertiarybutyl-amine (tBNH2) was extensively used in this work, because it is one of the most useful dopant sources in photo-assisted MOVPE of widegap II-VI compounds. Oscillations with monolayer periodicity in RD signal traces have been successfully detected for the first time using a He-Ne laser beam in MOVPE of ZnSe. One of the most important findings is that tBNH2 molecules are selectively adsorbed on the "Zn-terminated" surface and not on the "Se-terminated" surface
    this suggests that selective doping during Zn-source (DMZn) supply and/or on Zn-terminated surfaces will be effective for improving the doping efficiency.

    DOI

  • Formation of a thin III-VI compound interfacial layer at ZnTe/ZnSe heterojunction and its effect on energy band discontinuity

    T. Yoshida, T. Nagatake, M. Kobayashi, A. Yoshikawa

    Journal of Electronic Materials   25 ( 2 ) 195 - 199  1996年

     概要を見る

    Interfacial layers were inserted at the interface of ZnSe and ZnTe in order to reduce both (1) the effect of strain and (2) the valence band discontinuity. The interfacial layer adapted in this study is the III-VI compound (Ga,Se). The layered structure GaSe is favorable for the present work, because it can be a buffer layer to relax the lattice mismatch at the interface. All layers including ZnTe, (Ga,Se) and ZnSe were grown on (100) GaAs substrate by conventional molecular beam epitaxy. The crystal structure of the (Ga,Se) on ZnSe was investigated. The growth of the layered structure GaSe layer on (100) ZnSe was very difficult, though the defect zinc-blende structure Ga2Se3 layer could be easily grown. The defect zinc-blende structure Ga2Se3 was inserted at the interface of ZnSe and ZnTe so that the valence band discontinuity could be modified. The discontinuity was decreased to about 0.1 eV when the thickness of the interfacial layer was about 8Å. The current-voltage characteristics were measured for the sample with Ga2Se3 interfacial layer. The structure with Ga2Se3 exhibited the ohmic property. These results suggest that the valence band discontinuity between ZnTe and ZnSe can be reduced by introducing the Ga2Se3 interfacial layer.

    DOI

  • New in-situ optical probing method with an atomic scale resolution for thin film deposition: surface photo-interference (SPI)

    Y. Nakamura, T. Yamashita, M. Kobayashi, Y. Kato, A. Yoshikawa

    Proceedings of the IEEE/CPMT International Electronic Manufacturing Technology (IEMT) Symposium     387 - 390  1995年12月

     概要を見る

    A new in-situ optical probing method with an atomic-scale resolution in thin film deposition and/or heteroepitaxial growth is proposed in this paper. The new method is named surface photo-interference (SPI) because it is essentially concerned with a photo-interference in the deposited layer. The principle of the SPI is as follows; the complex refractive indices of the atomic or molecular layers, which alternately appear on top of the surface during film deposition and/or heteroepitaxy, greatly affect the total phase-shift of probing light during propagation in the epilayer, resulting in the change in the photo-interference signal intensity. The experimental setup of the method is very similar to that for another optical probing method called surface photo-absorption (SPA), but the principle is quite different between those two. One of the features of the SPI is that the experimental setup is quite simple and inexpensive though it is quite useful in real time monitoring of the thin film deposition.

  • TEMPERATURE-DEPENDENCE OF STRAIN IN ZNSE(EPILAYER)/GAAS(EPILAYER)

    RJ THOMAS, B ROCKWELL, HR CHANDRASEKHAR, M CHANDRASEKHAR, AK RAMDAS, M KOBAYASHI, RL GUNSHOR

    JOURNAL OF APPLIED PHYSICS   78 ( 11 ) 6569 - 6573  1995年12月

     概要を見る

    A study of biaxial strain as a function of temperature in a ZnSe epilayer grown on a GaAs substrate is presented. The strains are determined by measuring the heavy- and light-hole related excitonic transitions via photomodulated spectroscopy. The strain is found to increase with increasing temperature. The data are compared with a calculation using a previously determined elastic constant and thermal expansion coefficients. The temperature dependence determined here allows a comparison of various other optical measurements performed at different temperatures. (C) 1995 American Institute of Physics.

    DOI

  • DESIGN OF PSEUDO-TERNARY AND QUATERNARY ALLOYS BY SUPERLATTICES CONSISTING OF (ZN,CD)(S,SE) BINARY II-VI COMPOUNDS

    AW JIA, M KOBAYASHI, A YOSHIKAWA

    JOURNAL OF ELECTRONIC MATERIALS   24 ( 3 ) 117 - 121  1995年03月  [査読有り]

     概要を見る

    Theoretical design of pseudo-ternary and quaternary alloys by superlattice structures consisting of(Zn,Cd)(S,Se) binary II-VI compounds has been studied. For pseudo-ternary ZnCdS and ZnCdSe alloys, the superlattices with two layers in a cycle, i.e., ZnS/CdS and ZnSe/CdSe are considered, and for pseudo-quaternary ZnCdSSe alloy, the two superlattice structures with more than two layers in a cycle are considered. In order to design and evaluate these superlattices, the expression for the equilibrium in-plane lattice constant of these superlattices has been derived by minimizing the total elastic strain energy in the cycle. The combinations of layer thicknesses in a cycle and the effective bandgap of these superlattices have been calculated while the elastic strain effect was included. The usefulness of these superlattice structures has been evaluated.

    DOI

  • ZNSE-BASED WIDEGAP II-VI LIGHT EMITTERS FABRICATED BY LOW-TEMPERATURE EPITAXY - PRESENT STATUS AND PROSPECTS

    A YOSHIKAWA, M KOBAYASHI

    JOURNAL OF THE KOREAN PHYSICAL SOCIETY   28   S32 - S36  1995年02月  [査読有り]

     概要を見る

    In this paper, recent advances in the temperature epitaxy of the ZnSe-based widegap II-VI compounds on GaAs and their application to blue/green laser and light emitting diodes are discussed. It is shown that the maximum net acceptor concentration in the these widegap II-VI compounds is saturated at about 2X10(18) cm(-3), although several attempts to improve the maximum concentration have been done. As for the life time of blue/green laser diodes, the degradation of devices has been correlated to the propagation of crystal defects generated during growth. To reduce these defects such as stacking faults, it is believed now that incorporation of GaAs buffer layer is a useful and necessary technique. This indicates that double-chamber MBE system, in which GaAs buffer and laser structure are grown in different chambers connected through high- vacuum tunnel. The results when using ''epi-ready'' GaAs substrate which was grown in a separate MBE system are also briefly discussed. Further, recent advances in p-type doping in MOVPE-based growth are briefly shown.

  • Growth Kinetics in MOMBE‐ALE of ZnSe and CdSe as Determined by a New In‐Situ Optical Probing Method

    A. Yoshikawa, M. Kobayashi, S. Tokita

    physica status solidi (b)   187 ( 2 ) 315 - 325  1995年

     概要を見る

    The surface reaction mechanism in MOMBE‐ALE of ZnSe and CdSe using DMZn, DMCd, and H2Se as reactants is studied with a newly developed optical in‐situ monitoring method. The new method is named surface photo‐interference (SPI), because the concept of the SPI is essentially concerned with a photo‐interference in the heteroepilayer. Fairly low‐energy photons for which the epilayer is transparent can be used as probing light in SPI. Reflecting this feature, SPI is especially useful for studying heteroepitaxial growth kinetics of wide‐gap II‐VI compounds, because the effect of photocatalytic growth rate enhancement can be avoided when using such low energy photons as probing light. It is shown that there is a quite significant difference in the surface reaction mechanism between the MOMBE‐ALE of ZnSe and CdSe. That is, in the ALE of ZnSe when none of the source gases are per‐cracked, the reaction to form ZnSe can take place when the group‐II source (i.e., DMZn) is supplied, resulting in an alternate appearance of Zn terminated and H2Se terminated surfaces during growth. On the other hand, the reaction to form CdSe can do when the group‐VI source (i.e., H2Se) is supplied, resulting in an alternate appearance of Se terminated and DMCd terminated surfaces during growth. Copyright © 1995 WILEY‐VCH Verlag GmbH &amp; Co. KGaA

    DOI

  • MBE growth of sulfur-based binary and ternary widegap II-VI alloys using elemental sulfur source

    AW JIA, T YAMADA, M KOBAYASHI, A YOSHIKAWA

    II-VI COMPOUNDS AND SEMIMAGNETIC SEMICONDUCTORS   182-   403 - 406  1995年

     概要を見る

    We report on the molecular beam epitaxial (MBE) growth of sulfur-based binary and ternary widegap II-VI alloys using elemental sulfur source. The growth temperatures used arranged from 180 to 310°C. The valved-cracker cell with three independently controllable heaters is used for the S source. The epitaxial layers were grown using thermally cracked S source at 200, 500 and 900°C, and the film quality was characterized by X-ray diffraction and photoluminescence.

  • Theoretical design of 460 nm zncdsse laser diodes

    Wataru Imajuku, Masashi Takahashi, Masakazu Kobayash, Akihiko Yoshikawa

    Japanese Journal of Applied Physics   34 ( 4R ) 1861 - 1866  1995年

     概要を見る

    Theoretical design of ZnSSe/ZnCdSSe laser diodes emitting 460 nm at room temperature (RT) was studied by means of threshold current analysis. The threshold current density calculation was based on the laser theoryestablished for the III-V laser diode (LD) system. The result of the threshold current density calculation indicatedthat the reduction of carrier overflow is an essential issue in realizing the device with a reasonable threshold currentlevel at RT. Another indication is that 30% S content in the ZnSSe cladding layer would be a suitable targetvalue for a practical 460 nm LD at RT, along with a multiple quantum barrier structure. The predicted thresholdcurrent density of such a LD could be as low as 450 A/cm2 at RT. © 1995 The Japan Society of Applied Physics.

    DOI

  • OBSERVATION OF A NEW IN-SITU OPTICAL MONITORING SIGNAL WITH MONOLAYER RESOLUTION IN METALORGANIC MOLECULAR-BEAM EPITAXY AND METALORGANIC VAPOR-PHASE EPITAXY OF WIDE-GAP II-VI COMPOUNDS

    A YOSHIKAWA, M KOBAYASHI, S TOKITA

    JOURNAL OF CRYSTAL GROWTH   145 ( 1-4 ) 68 - 73  1994年12月

     概要を見る

    A new in-situ optical probing method for studying surface reactions during heteroepitaxial growth is proposed. The new method is named surface photo-interference (SPI), because the concept of the SPI is essentially concerned with a photo-interference in the heteroepilayer. The experimental setup of the method is very similar to another optical probing method called surface photo-absorption (SPA), but the principle is quite different between the two. Unlike SPA, fairly low energy photons that are transparent for the epilayer can also be used in SPI as a probing light. Reflecting this feature, SPI is especially useful for studying growth kinetics in heteroepitaxial growth of widegap II-VI compounds, because the effect of photocatalytic growth-rate enhancement can be avoided when using such low energy photons as a probing light. A brief theoretical description of SPI signal is given, and experimental results detected in metalorganic molecular beam energy (MOMBE) of ZnSe and CdSe are mainly discussed. Further, how SPI differs from SPA will be shown.

    DOI

  • SURFACE-REACTION MECHANISM IN MOMBE-ALE OF ZNSE AND CDSE AS DETERMINED BY A NEW IN-SITU OPTICAL PROBING METHOD

    A YOSHIKAWA, M KOBAYASHI, S TOKITA

    APPLIED SURFACE SCIENCE   82-3   316 - 321  1994年12月

     概要を見る

    The surface reaction mechanism in MOMBE-ALE of ZnSe and CdSe using DMZn, DMCd and H2Se as reactants has been studied with a newly developed optical in-situ monitoring method named surface photo-interference (SPI). It is shown that there is a quite significant difference in the surface reaction mechanism between the MOMBE-ALE of ZnSe and CdSe. That is, in the ALE of ZnSe when none of the source gases are pre-cracked, the reaction to form ZnSe can take place when the group-II source (i.e., DMZn) is supplied, resulting in an alternate appearance of Zn-terminated and H2Se-terminated surfaces during growth. On the other hand, the reaction to form CdSe can take place when a group-VI source (i.e., H2Se) is supplied, resulting in an alternate appearance of Se-terminated and DMCd-terminated surfaces during growth.

    DOI

  • A NEW IN-SITU OPTICAL PROBING METHOD FOR THE SURFACE-REACTION IN PHOTO-EXCITED HETEROEPITAXY OF COMPOUND SEMICONDUCTORS

    A YOSHIKAWA, M KOBAYASHI, S TOKITA

    APPLIED SURFACE SCIENCE   79-80   416 - 421  1994年05月

     概要を見る

    A new in-situ optical probing method with an atomic-scale resolution in heteroepitaxial growth is proposed. The experimental set-up of the method is very similar to another optical probing method called surface photo-absorption (SPA), but the principle is quite different. The new method is named surface photo-interference (SPI) because it is essentially concerned with photo-interference in the heteroepilayer. The principle of the SPI is as follows: the complex refractive indices of the atomic or molecular layers, which alternately appear on top of the surface during epitaxial growth of compound semiconductors, greatly affect the total phase shift of probing light during propagation in the epilayer, resulting in a change in the photo-interference signal intensity. One of the features of the SPI is that, unlike in the case of SPA, fairly low energy photons which are transparent for the epilayer can also be used as probing light. This is very preferable for studying the growth kinetics and/or surface reaction in photo-excited epitaxial growth of widegap II-VI compounds, because the effect of photocatalytic growth-rate enhancement can be avoided when using such low energy photons as probing light.

    DOI

  • HELIUM GAS MIXING IN NITROGEN PLASMA FOR THE CONTROL OF THE ACCEPTOR CONCENTRATION IN P-ZNSE

    M KOBAYASHI, H TOSAKA, T NAGATAKE, T YOSHIDA, A YOSHIKAWA

    JOURNAL OF CRYSTAL GROWTH   138 ( 1-4 ) 745 - 749  1994年04月

     概要を見る

    Nitrogen and helium mixed gas plasma was used to control the acceptor concentration of p-ZnSe and p-ZnSSe. Using the mixed gas, the acceptor concentration of p-ZnSe can be controlled from 6 X 10(16) to 7 X 10(17) cm-3, whereas the acceptor concentration of p-ZnSSe can be controlled from 4 X 10(16) to 4 X 10(17) cm-3 . Doping characteristics such as the acceptor concentration and the PL properties depend on the gas mixing ratio and the RF power. p-Layers grown with this technique were used for blue-green laser diode structures. Lasing was observed at 77 K under pulsed operation.

    DOI

  • IN-SITU PROBING OF THE ZNSE METALORGANIC MOLECULAR-BEAM EPITAXY GROWTH-PROCESS BY SURFACE PHOTO-INTERFERENCE METHOD

    S TOKITA, M KOBAYASHI, A YOSHIKAWA

    JOURNAL OF CRYSTAL GROWTH   136 ( 1-4 ) 376 - 380  1994年03月

     概要を見る

    The metalorganic molecular beam epitaxy (MOMBE) growth process of ZnSe on GaAs was characterized by the surface photo-interference (SPI) method. The SPI signal traces were monitored in various experiments where the source gas cracking conditions were varied. The signal features, such as intensity and polarity, were drastically modified by the Se source gas cracking, whereas the signal was hardly affected by the Zn source gas cracking. Zn-terminated surfaces formed by uncracked dimethylzinc (DMZn) gas supply as well as the cracked gas supply are likely to be covered with Zn atoms. On the other hand, the Se-terminated surface formed by the uncracked H2Se gas supply is probably covered with H2Se molecules.

    DOI

  • GaAsに格子整合する超格子によるZnCdSSe擬似四元混晶の設計

    賈 岸偉, 小林 正和, 吉川 明彦

    電気学会論文誌E(センサ・マイクロマシン部門誌)   114 ( 12 ) 1286 - 1291  1994年

     概要を見る

    In this paper, we propose two superlattice structures as pseudo-quaternary ZnCdSSe layers. They consist of three layers or four layers in a cycle with three kinds of binary compound materials, i.e., ZnS, ZnSe and CdS. In order to estimate the equilibrium in-plane lattice constant of these layers, a general expression for superlattices consisting of n (n=2, 3, 4, &amp;hellip;) layers in a cycle has been derived by minimizing the total elastic strain energy. The effective bandgap for the superlattices with different combinations of the layer thickness in a cycle were calculated using Kronig-Penney model, where the strain effect was taken into account in calculating the bandgap and the band offset. The calculated results of the effective bandgaps were compared with the bandgap of ZnCdSSe quaternary alloy.

    DOI CiNii

  • RAMAN AND MODULATED-REFLECTIVITY SPECTRA OF A STRAINED PSEUDOMORPHIC ZNTE EPILAYER ON INAS UNDER PRESSURE

    RJ THOMAS, MS BOLEY, HR CHANDRASEKHAR, M CHANDRASEKHAR, C PARKS, AK RAMDAS, J HAN, M KOBAYASHI, RL GUNSHOR

    PHYSICAL REVIEW B   49 ( 3 ) 2181 - 2184  1994年01月

     概要を見る

    The piezomodulated-, electromodulated-, and photomodulated-reflectivity spectra of a pseudomorphic ZnTe epilayer, grown on an InAs epilayer by molecular-beam epitaxy, exhibit heavy- and light-hole excitonic signatures split by the lattice mismatch induced biaxial compressive strain. This splitting in the pseudomorphic epilayer is studied as a function of applied hydrostatic pressure using photomodulated reflectance spectroscopy at 80 K. With increasing hydrostatic compression, the compressive strain is progressively compensated by the pressure-induced tensile strain. At similar to 55 kbars the epilayer becomes strain-free, and is under a biaxial tension at higher pressures. The separation between the heavy- and light-hole signatures is superlinear in pressure, suggestive of a strain or volume deformation-dependent shear deformation-potential constant. We also compare the pressure dependence of she Raman LO phonon of the ZnTe epilayer on InAs with that of a bulk ZnTe sample at 13 K. The pressure-dependent strain is found to be linear. Accurate values of the first-order strain derivatives of the LO phonons and mode Gruneisen constants are obtained.

    DOI

  • ACCEPTOR CONCENTRATION CONTROL OF P-ZNSE USING N2+HE GAS PLASMA BY MOLECULAR-BEAM EPITAXY

    M KOBAYASHI, A YOSHIKAWA

    COMPOUND SEMICONDUCTOR EPITAXY   340   437 - 445  1994年

     概要を見る

    Nitrogen and helium mixed gas plasma was used to grow p-ZnSe. Using the mixed gas, the acceptor concentration could be controlled from 6×1016 to 7×1017 cm-3 while films doped using the nitrogen plasma exhibited the acceptor concentration of 3×1017 cm-3. Doping characteristics such as the acceptor concentration and the PL properties depend on the gas mixing ratio and the rf power. Plasma spectroscopy was used to characterize the variety of the species in the plasma. Although the variety of the nitrogen related peaks in the spectrum were not significantly affected by the gas mixing, several peaks (for example 745nm and 825nm) showed intensity variation that was similar to the acceptor concentration variation with respect to the N2 and He gas mixing ratio.

  • Heavy p-doping of ZnTe by molecular beam epitaxy using a nitrogen plasma source

    J. Han, T. S, Stavrinides, M. Kobayashi, R. L. Gunshor, M. M. Hagerott, A. V. Nurmikko

    Applied Physics Letters   62   840 - 842  1993年12月

     概要を見る

    The successful p-doping of ZnSe and Zn(S,Se) using a nitrogen plasma source during growth by molecular beam epitaxy has been an important factor leading to the recent realization of blue-green diode lasers and light-emitting diodes. This letter reports the results of the nitrogen doping of ZnTe using similar techniques. Doping levels approaching the 1019cm-3range are reported along with electrical, optical, and microstructural characterization. Highly doped ZnTe provides an opportunity for forming an ohmic contact to p-ZnSe.

    DOI

  • Pressure tuning of strain in CdTe/InSb epilayer: A photoluminescence and photomodulated reflectivity study

    Mark S. Boley, Robert J. Thomas, Meera Chandrasekhar, H. R. Chandrasekhar, A. K. Ramdas, M. Kobayashi, R. L. Gunshor

    Journal of Applied Physics   74   4136 - 4144  1993年12月  [査読有り]

     概要を見る

    The heavy-hole and light-hole excitons of a CdTe epilayer, pseudomorphically grown on an InSb epilayer by molecular beam epitaxy, are studied with a diamond anvil cell as a function of applied hydrostatic pressure via photoluminescence (PL) and photomodulated reflectivity (PR) spectroscopies. They are compared with the excitonic features in the simultaneously measured PL spectra of a sample of bulk CdTe. Under applied pressure, the lattice mismatch-induced splitting between the light-hole and heavy-hole related transitions increases in a continuous and reversible manner because of the additional pressure-induced compression due to the difference in the compressibilities of CdTe and InSb. The unusually large strain sustained by the CdTe epilayer under pressure is discussed in the light of various models. The PR signal vanishes after the InSb epilayer goes through a structural phase transition at approximately 20 kbar, while the PL signal persists until it is irreversibly quenched by the CdTe epilayer undergoing a structural phase transition at approximately 30 kbar. For pressures between 20 and 30 kbar, the behavior of the CdTe epilayer is similar to that of the bulk sample; the strain appears to have been relaxed due to the structural phase transition which has taken place in InSb. Values of the first- and second-order pressure coefficients for bulk CdTe and for the CdTe epilayer as well as values of the hydrostatic and shear deformation potentials are obtained at 14 and 80 K and compared with previously quoted values.

    DOI

  • PRESSURE TUNING OF STRAIN IN CDTE/INSB EPILAYER - A PHOTOLUMINESCENCE AND PHOTOMODULATED REFLECTIVITY STUDY

    MS BOLEY, RJ THOMAS, M CHANDRASEKHAR, HR CHANDRASEKHAR, AK RAMDAS, M KOBAYASHI, RL GUNSHOR

    JOURNAL OF APPLIED PHYSICS   74 ( 6 ) 4136 - 4144  1993年09月  [査読有り]

     概要を見る

    The heavy-hole and light-hole excitons of a CdTe epilayer, pseudomorphically grown on an InSb epilayer by molecular beam epitaxy, are studied with a diamond anvil cell as a function of applied hydrostatic pressure via photoluminescence (PL) and photomodulated reflectivity (PR) spectroscopies. They are compared with the excitonic features in the simultaneously measured PL spectra of a sample of bulk CdTe. Under applied pressure, the lattice mismatch-induced splitting between the light-hole and heavy-hole related transitions increases in a continuous and reversible manner because of the additional pressure-induced compression due to the difference in the compressibilities of CdTe and InSb. The unusually large strain sustained by the CdTe epilayer under pressure is discussed in the light of various models. The PR signal vanishes after the InSb epilayer goes through a structural phase transition at approximately 20 kbar, while the PL signal persists until it is irreversibly quenched by the CdTe epilayer undergoing a structural phase transition at approximately 30 kbar. For pressures between 20 and 30 kbar, the behavior of the CdTe epilayer is similar to that of the bulk sample; the strain appears to have been relaxed due to the structural phase transition which has taken place in InSb. Values of the first- and second-order pressure coefficients for bulk CdTe and for the CdTe epilayer as well as values of the hydrostatic and shear deformation potentials are obtained at 14 and 80 K and compared with previously quoted values.

    DOI

  • MBE GROWTH AND MICROSTRUCTURAL EVALUATION OF ZN(S,SE)-BASED LEDS AND DIODE-LASERS

    DC GRILLO, W XIE, M KOBAYASHI, RL GUNSHOR, GC HUA, N OTSUKA, H JEON, J DING, AV NURMIKKO

    JOURNAL OF ELECTRONIC MATERIALS   22 ( 5 ) 441 - 444  1993年05月

     概要を見る

    The use of a nitrogen radio frequency plasma source together with an appropriate quantum well configuration have recently resulted in the successful realization of p-type ZnSe by molecular beam epitaxy. This has enabled a variety of pn heterojunction based devices to be built including the first semiconductor injection lasers operating in the blue/green portion of the spectrum first reported by 3M and the Brown/Purdue group. In this paper, we discuss two lattice matched multiple quantum well structures that produce laser emission in the blue and blue/green portion of the spectrum.

    DOI

  • GROWTH AND CHARACTERIZATION OF ZNTE-N-P-ZNTE/N-ALSB DIODES

    J HAN, TS STAVRINIDES, M KOBAYASHI, RL GUNSHOR, MM HAGEROTT, AV NURMIKKO

    JOURNAL OF ELECTRONIC MATERIALS   22 ( 5 ) 485 - 488  1993年05月

     概要を見る

    In recent months the successful p-doping of ZnSe and Zn(S,Se) using a nitrogen plasma source during growth by molecular beam epitaxy was one factor leading to the realization of diode lasers and light emitting diodes. This paper reports the results of the nitrogen doping of ZnTe using similar techniques. Doping levels exceeding the 10(19) CM-3 range are reported along with electrical, optical, and microstructural characterization. The nitrogen-doped ZnTe is used to implement p-ZnTe/n-AlSb diodes; the growth and characterization of these heterojunction diodes are described.

    DOI

  • BLUE AND BLUE-GREEN LASER-DIODES AND LED-BASED DISPLAY DEVICES

    W XIE, DC GRILLO, M KOBAYASHI, L HE, RL GUNSHOR, H JEON, J DING, AV NURMIKKO, GC HUA, N OTSUKA

    JOURNAL OF CRYSTAL GROWTH   127 ( 1-4 ) 287 - 290  1993年02月

     概要を見る

    We describe the performance of pn junction MOW diode lasers and LEDs which are grown on both p-type and n-type GaAs substrates. Efforts to minimize dislocations by lattice matching the II-VI region to the GaAs substrate in some cases resulted in obtaining dislocation densities below 10(5) cm-2. We have obtained pulsed high power, high quantum efficiency laser emission up to room temperature conditions, and continuous operation at liquid nitrogen temperatures. Efficient LED and display devices operate in the blue (490-494 nm) at room temperature.

    DOI

  • Acceptor concentration control of p-znse using nitrogen and helium mixed gas plasma

    Hiroyuki Tosaka, Tsuyoshi Nagatake, Takashi Yoshida, Masakazu Kobayashi, Akihiko Yoshikawa

    Japanese Journal of Applied Physics   32 ( 12 A ) L1722 - L1724  1993年

     概要を見る

    Nitrogen and helium mixed gas plasma was used to grow p-ZnSe. Using the mixed gas, the acceptor concentration can be controlled from 6 x 1016to 7 x 1017cm-3while films doped using the nitrogen plasma exhibited the acceptor concentration of 3 x 1017cm-3. Doping characteristics such as the acceptor concentration and the PL properties depend on the gas mixing ratio and the rf power. p-ZnSe layers grown with this technique were used for blue-green laser structures. Lasing was observed at 77 K under pulse operation. © 1993 The Japan Society of Applied Physics.

    DOI

  • Planar-Doping of Molecular Beam Epitaxy Grown Znse With Plasma-Excited Nitrogen

    Shigeyuki Matsumoto, Hiroyuki Tosaka, Takashi Yoshida, Masakazu Kobayashi, Akihiko Yoshikawa

    Japanese Journal of Applied Physics   32 ( 2 B ) L229 - L232  1993年

     概要を見る

    Planar doping of nitrogen into ZnSe is examined. The dependence of doping efficiency on the particular surface termination (Zn- or Se-stabilised) on (100) ZnSe is investigated through capacitance-voltage measurement and low-temperature photoluminescence (PL) spectroscopy. Using planar doping on the Zn surface, we achieved a hole concentration of 4.5 x 1017 cm-3, and the PL spectrum is dominated by strong donor-acceptor pair (DAP) emissions. By contrast, the film planar-doped on the Se plane shows rather low hole concentration, and the spectrum is dominated by excitonic features along with very weak DAP emissions. © 1993 The Japan Society of Applied Physics.

    DOI

  • Nitrogen doping of znse and zncdse with the assistance of thermal energy and photon energy

    Shigeyuki Matsumoto, Hiroyuki Tosaka, Takashi Yoshida, Masakazu Kobayashi, Akihiko Yoshikawa

    Japanese Journal of Applied Physics   32 ( 8 R ) 731 - 735  1993年

     概要を見る

    Two methods were examined for doping nitrogen into ZnSe and ZnCdSe. N2gas was thermally excited in the first method. The photoluminescence (PL) spectra showed that acceptor levels were formed in the film
    this feature was similar to that observed in the samples doped with nonexcited N2gas. The second method utilized pho-toexcited N2O and N2gases using vacuum ultraviolet (VUV) light. A deuterium lamp was used for the VUV-light source. Deep-emission-dominant PL spectra were observed when films were doped using photoexcited N2O gas. N2O gas was then mixed with N2gas to control the photodecomposition process and improve the film quality. Samples doped using the mixed gas exhibited well-resolved near-band-edge features. The PL spectrum of the ZnO.9 Cdo.iSe sample doped using the photoexcited mixed gas showed donor-acceptor pair emission. © 1993 The Japan Society of Applied Physics.

    DOI

  • PULSED ROOM-TEMPERATURE OPERATION OF A BLUE-GREEN ZNSE QUANTUM-WELL DIODE-LASER

    H JEON, M HAGEROTT, J DING, AV NURMIKKO, DC GRILLO, W XIE, M KOBAYASHI, RL GUNSHOR

    OPTICS LETTERS   18 ( 2 ) 125 - 127  1993年01月

     概要を見る

    Low-threshold current density operation has been obtained from (Zn, Cd)Se/Zn(S, Se) quantum-well diode lasers in the blue-green spectrum. The devices, with reflective facet coatings, have been operated at room temperature under pulsed conditions with threshold current densities of I(th) almost-equal-to 1 kA/cm2.

    DOI

  • ZnSe based multilayer pn junctions as efficient light emitting diodes for display applications

    H. Jeon, J. Ding, A. V. Nurmikko, W. Xie, M. Kobayashi, R. L. Gunshor

    Applied Physics Letters   60   892 - 894  1992年12月

     概要を見る

    pn junction characteristics and LED action in ZnSe-based multilayers grown by molecular beam epitaxy is demonstrated. In particular, we show that (Zn,Cd)Se/ZnSe/Zn(S,Se) structures containing (Zn,Cd)Se quantum wells, grown on p-type GaAs epilayers, and designed with a heavily doped n+-ZnSe top contact layer may be appropriate for display device applications in the blue-green portion of the spectrum.

    DOI

  • Blue and green diode lasers in ZnSe-based quantum wells

    H. Jeon, J. Ding, A. V. Nurmikko, W. Xie, D. C. Grillo, M. Kobayashi, R. L. Gunshor, G. C. Hua, N. Otsuka

    Applied Physics Letters   60   2045 - 2047  1992年12月

     概要を見る

    Laser diode operation has been obtained from (Zn,Cd)Se/ZnSe and (Zn,Cd)Se/Zn(S,Se) quantum well structures in the blue and the green. The devices, prepared on p- and n-type (In,Ga)As or GaAs buffer layers for lattice matching purposes to control the defect density, have been operated at near-room-temperature conditions and briefly at room temperature with uncoated end facets. Quasi-continuous wave operation has been obtained at T=77 K.

    DOI

  • Blue/green pn junction electroluminescence from ZnSe-based multiple quantum-well structures

    W. Xie, D. C. Grillo, R. L. Gunshor, M. Kobayashi, G. C. Hua, N. Otsuka, H. Jeon, J. Ding, A. V. Nurmikko

    Applied Physics Letters   60   463 - 465  1992年12月

     概要を見る

    The successful p doping of ZnSe by substitutional nitrogen using a plasma cell incorporated into the molecular beam epitaxy chamber has led to the development of electroluminescent devices based on carrier injection at a pn junction. The light emitting diode structures described here are grown on a GaAs substrate using a tetragonally distorted (In,Ga)As buffer layer to provide lattice matching between the substrate and the active II-VI region. The result of the incorporation of the buffer layer is an essentially dislocation-free active region. The letter discusses optical properties as well as the x-ray and transmission electron microscopy characterization of the quantum well device structures.

    DOI

  • QUANTUM-WELLS, EXCITONS, AND LASERS AT BLUE-GREEN WAVELENGTHS IN ZNSE-BASED HETEROSTRUCTURES

    AV NURMIKKO, RL GUNSHOR, M KOBAYASHI

    JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B   10 ( 4 ) 2056 - 2061  1992年07月  [査読有り]

     概要を見る

    Recent developments were reviewed in ZnSe-based quantum wells and heterostructures with emphasis on physics and engineering towards light emitter applications at blue-green wavelengths. To illustrate current progress, examples are given of both diode laser and light emitting diode device research.

    DOI

  • MBE growth of widegap II-VI injection lasers and LEDs

    Masakazu Kobayashi, Robert L. Gunshor, Arto V. Nurmikko, Nobuo Otsuka

    Optoelectronics Tokyo   7   1 - 10  1992年06月

     概要を見る

    The successful p-doping of ZnSe by substitutional nitrogen using a plasma cell incorporated into a molecular beam epitaxy chamber has led to the development of electroluminescent devices employing carrier injection at a p-n junction and in which the active region is based on (Zn,Cd) Se/Zn(S,Se) multiple quantum well structures. We report on the performance of p-n junction MQW diode lasers and LEDs which are grown on both p-type and n-type GaAs substrates, and where sulfur is, or is not incorporated. For all structures, efforts were made to minimize dislocations by lattice matching the active II-VI region to the GaAs substrate. Some designs have dislocation densities below 105 cm-2. In this work we have obtained pulsed high power, high quantum efficiency laser emission up to room temperature conditions, and continuous operation at liquid nitrogen temperatures. Efficient LED devices are described which operate in the blue (494 nm) at room temperature.

  • INDIUM TIN OXIDE AS TRANSPARENT ELECTRODE MATERIAL FOR ZNSE-BASED BLUE QUANTUM-WELL LIGHT EMITTERS

    M HAGEROTT, H JEON, AV NURMIKKO, W XIE, DC GRILLO, M KOBAYASHI, RL GUNSHOR

    APPLIED PHYSICS LETTERS   60 ( 23 ) 2825 - 2827  1992年06月

     概要を見る

    Sputter deposited indium tin oxide layers have been used as the top contact for blue LEDs and diode lasers in (Zn,Cd)Se/Zn(S,Se) quantum well heterostructures. The contact resistance to n-Zn(S,Se) is comparable to that with indium or gold. The optically transparent contacts have been utilized, as an example, in the fabrication of a numeric display device and to show that LED emission is of excitonic origin in these type I quantum wells.

    DOI

  • ROOM-TEMPERATURE BLUE-LIGHT EMITTING P-N DIODES FROM ZN(S,SE)-BASED MULTIPLE QUANTUM-WELL STRUCTURES

    W XIE, DC GRILLO, RL GUNSHOR, M KOBAYASHI, H JEON, J DING, AV NURMIKKO, GC HUA, N OTSUKA

    APPLIED PHYSICS LETTERS   60 ( 16 ) 1999 - 2001  1992年04月

     概要を見る

    Blue (494 nm) light emitting quantum well diodes based on Zn(S,Se) p-n junctions are demonstrated at room temperature. P-type Zn(S,Se) is realized by using a nitrogen rf plasma cell. The light emitting diode is formed on homoepitaxial GaAs buffer layers by molecular beam epitaxy. The S fraction of the alloy is selected to provide a lattice match between the II-VI active region and the GaAs buffer; the result is an active region having a dislocation density below 10(5)/cm-2. The letter discusses emission characteristics as well as the x-ray rocking curve and transmission electron microscopy characterization of the structures.

    DOI

  • II-VI SEMICONDUCTORS COME OF AGE

    R GUNSHOR, A NURMIKKO, M KOBAYASHI

    PHYSICS WORLD   5 ( 3 ) 46 - 49  1992年03月  [査読有り]

  • BLUE GREEN INJECTION-LASERS AND LIGHT-EMITTING-DIODES

    W XIE, DC GRILLO, RL GUNSHOR, M KOBAYASHI, GC HUA, N OTSUKA, H JEON, J DING, AV NURMIKKO

    JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B   10 ( 2 ) 921 - 923  1992年03月  [査読有り]

     概要を見る

    The p doping of molecular-beam epitaxially grown ZnSe by substitutional nitrogen using a plasma cell has enabled the fabrication of pn junction injection electroluminescent devices. The light emitting diode structures, including pulsed laser diodes described here, are grown on GaAs substrates and incorporate multiple quantum well structures as the active gain region. This article discusses optical properties as well as the x-ray and transmission electron microscopy (TEM) characterization of the quantum well device structures. The TEM imaging reveals low dislocation densities in both device configurations.

    DOI

  • OPTICAL-PROPERTIES AND DEVICE PROSPECTS OF ZNSE-BASED QUANTUM STRUCTURES

    AV NURMIKKO, RL GUNSHOR, M KOBAYASHI

    JOURNAL OF CRYSTAL GROWTH   117 ( 1-4 ) 432 - 440  1992年02月

     概要を見る

    The optical properties of (Zn,Cd)Se/ZnSe quantum wells are reviewed with emphasis on recent results on quasi-two-dimensional excitons, light emitting diodes, as well as on optically pumped lasers and diode lasers in this type I system.

    DOI

  • ZNSE/ZN0.8CD0.2SE QUANTUM-WELL LEDS AND LASERS

    W XIE, DC GRILLO, M KOBAYASHI, RL GUNSHOR, GC HUA, N OTSUKA, H JEON, J DING, AV NURMIKKO

    JOURNAL OF CRYSTAL GROWTH   117 ( 1-4 ) 1079 - 1079  1992年02月

    DOI

  • Growth and Characterization of ZnSe/ZnCdSe Diode Structures on (In,Ga)As Buffer Layers

    G.C. Hua, N. Otsuka, W. Xie, D.C. Grillo, M. Kobayashi, R.L. Gunshor

    Mat. Res. Soc. Symp. Proc.   242   208 - 211  1992年  [査読有り]

  • THE MBE GROWTH OF WIDE-GAP II-VI INJECTION-LASERS AND LEDS

    W XIE, DC GRILLO, M KOBAYASHI, RL GUNSHOR, H JEON, J DING, AV NURMIKKO, GC HUA, N OTSUKA

    WIDE BAND GAP SEMICONDUCTORS   242   203 - 214  1992年  [査読有り]

  • Vacancy ordering at heterovalent interfaces

    D. Li, Y. Nakamura, N. Otsuka, J. Qiu, M. Kobayashi, R. L. Gunshor

    Surface Science   267   181 - 186  1992年01月

     概要を見る

    Atomic structures of three Ga2Se3epilayers grown on GaAs(100) or ZnSe(100) epilayers by molecular beam epitaxy were studied by transmission electron microscopy. A new vacancy ordered structure was found in the heteroepitaxial interface regions of Ga2Se3epilayers. The ordered structure is described as an alternate stacking of two types of Ga planes in the growth direction. One half of the sites are vacancies in one type of Ga plane, while the other type of Ga plane is fully occupied by Ga atoms. Comparison of three Ga2Se3epilayers indicates a strong influence of surface chemistry of substrate epilayers on the formation of the vacancy ordering. A highly developed two-dimensional ordering has occured in the epilayer grown on a GaAs(100) surface with (4 × 3) rereconstructions. © 1992.

    DOI

  • IIIB-5 Blue and Blue/Green Laser Diodes and LED-Based Display Devices

    H. Jeon, M. Hagerott, J. Ding, A. V. Nurmikko, W. Xie, D. C. Grillo, M. Kobayashi, R. L. Gunshor, G. C. Hua, N. Otsuka

    IEEE Transactions on Electron Devices   39   2652 - 2653  1992年01月

    DOI

  • GROWTH AND CHARACTERIZATION OF ZNSE ZNCDSE DIODE STRUCTURES ON (IN,GA) AS BUFFER LAYERS

    GC HUA, N OTSUKA, W XIE, DC GRILLO, M KOBAYASHI, RL GUNSHOR

    WIDE BAND GAP SEMICONDUCTORS   242   221 - 226  1992年  [査読有り]

  • BLUE-GREEN INJECTION-LASER DIODES IN (ZN,CD)SE/ZNSE QUANTUM-WELLS

    H JEON, J DING, W PATTERSON, AV NURMIKKO, W XIE, DC GRILLO, M KOBAYASHI, RL GUNSHOR

    APPLIED PHYSICS LETTERS   59 ( 27 ) 3619 - 3621  1991年12月

     概要を見る

    Laser diode action in the blue-green has been observed from (Zn,Cd)Se quantum wells within ZnSe/Zn(S,Se) p-n heterojunctions up to 250 K. Operation is reported for two different configurations for which the GaAs substrate serves either as the n- or p-type injecting contact. In pulsed operation, output powers exceeding 0.6 W have been measured in devices prepared on both n-type and p-type GaAs epitaxial buffer layers and substrates.

    DOI

  • PROPERTIES OF II-VI/III-V HETEROVALENT INTERFACES

    RL GUNSHOR, M KOBAYASHI, N OTSUKA, AV NURMIKKO

    JOURNAL OF CRYSTAL GROWTH   115 ( 1-4 ) 652 - 659  1991年12月

     概要を見る

    The paper addresses two issues related to II-VI/III-V heterostructures. The first topic is a discussion of the nature of the bonding at CdTe/InSb and ZnSe/GaAs interfaces grown by molecular beam epitaxy. The bonding is studied by means of in situ X-ray photoelectron spectroscopy (XPS). A comparison of the In 3d core level features from an InSb epilayer surface, a Te-reacted InSb surface, very thin (a few monolayers thick) CdTe/InSb epilayer/epilayer heterostructures and from deliberately grown (In,Te) epilayers, indicate that the Te-reacted layer, the CdTe/InSb heterostructures and the (In,Te) epilayers exhibit similar In bonding characteristics. A parallel XPS study of ZnSe/GaAs interfaces reinforces the conclusion that there is a general tendency for the formation of a III-VI interfacial compound when forming II-VI/III-V junctions. The second topic concerns a description of pn junction light emitting devices based on ZnSe. In the structures described, carriers are injected from nitrogen doped p-ZnSe and chlorine doped n-ZnSe into a multiple quantum well structure having (Zn,Cd)Se wells and ZnSe barriers. The bright CW photon emission originates from quantum well transitions.

    DOI

  • PRESSURE TUNING OF STRAINS IN SEMICONDUCTOR HETEROSTRUCTURES - (ZNSE EPILAYER)/(GAAS EPILAYER)

    B ROCKWELL, HR CHANDRASEKHAR, M CHANDRASEKHAR, AK RAMDAS, M KOBAYASHI, RL GUNSHOR

    PHYSICAL REVIEW B   44 ( 20 ) 11307 - 11314  1991年11月  [査読有り]

     概要を見る

    The heavy-hole and light-hole excitons of a pseudomorphic ZnSe film grown on a GaAs epilayer by molecular-beam epitaxy, are studied as a function of applied hydrostatic pressure using photomodulated reflectance spectroscopy. At ambient pressure, the signature in the spectrum due to the heavy-hole exciton occurs at an energy lower than that of the light-hole exciton, a consequence of the compressive biaxial strain in ZnSe due to its lattice mismatch with GaAs. As the pressure is increased, the two signatures approach each other in energy and coalesce at 36.2 kbar. The difference in the compressibility of ZnSe from that of GaAs generates a tensile strain that progressively compensates the lattice-mismatch-induced compressive strain and finally, at 36.2 kbar, the heterostructure is strain free. Beyond this pressure, the strain in ZnSe transforms from biaxial compression to biaxial tension, the light-hole signature now occurring at the lower energy. The transformation of strains via pressure tuning is continuous and reversible. The separation between the heavy-hole and light-hole signatures is superlinear in pressure, suggestive of a pressure-dependent shear-deformation-potential constant.

    DOI

  • AN X-RAY PHOTOELECTRON-SPECTROSCOPY STUDY OF BONDING AT II-VI/III-V HETEROVALENT INTERFACES

    DR MENKE, J QIU, RL GUNSHOR, M KOBAYASHI, D LI, Y NAKAMURA, N OTSUKA

    JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B   9 ( 4 ) 2171 - 2175  1991年07月  [査読有り]

     概要を見る

    In this paper in situ x-ray photoelectron spectroscopy (XPS) is used to study the nature of the bonding at ZnSe/GaAs and CdTe/InSb interfaces grown by molecular-beam epitaxy. X-ray photoelectron spectra support the transmission electron microscopy evidence that ZnSe/GaAs MIS capacitors exhibiting low interface state densities are associated with the formation of an interfacial layer of zinc blende Ga2Se3. An interfacial layer can be deliberately introduced by reacting an As deficient GaAs surface with an incident Se flux. A comparison of the Se 3d core level features from the ZnSe epilayer surface, a Se-reacted GaAs surface, and from separately grown Ga2Se3 epilayers, clearly indicate the same Se bonding characteristic for the Se-reacted layer, and the Ga2Se3, epilayer. A parallel XPS study of CdTe/InSb interfaces leads to the conclusion that there is a general tendency for the formation of a III-VI interfacial compound when forming a II-VI-on-III-V junction.

    DOI

  • RECONSTRUCTION AT THE GA2SE3/GAAS EPITAXIAL INTERFACE

    D LI, Y NAKAMURA, N OTSUKA, J QIU, M KOBAYASHI, RL GUNSHOR

    JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B   9 ( 4 ) 2167 - 2170  1991年07月  [査読有り]

     概要を見る

    A highly developed two dimensional superstructure was found at the Ga2Se3/GaAs epitaxial interface by transmission electron microscope observations. The atomic arrangement of the superstructure was determined by the analysis of electron diffraction patterns and high resolution transmission electron microscope images. The structure is described as a c(2 x 2) ordered arrangement of vacancies on the interfacial Ga plane. A possible role of the mismatch of electronic configurations at the Ga2Se3/GaAs interface in the formation of the vacancy ordering is discussed.

    DOI

  • CHARACTERIZATION OF GA2SE3 AT ZNSE/GAAS HETEROVALENT INTERFACES

    J QIU, DR MENKE, M KOBAYASHI, RL GUNSHOR, D LI, Y NAKAMURA, N OTSUKA

    APPLIED PHYSICS LETTERS   58 ( 24 ) 2788 - 2790  1991年06月

     概要を見る

    Despite the valence difference across the junction, it has been shown that ZnSe/GaAs epilayer/epilayer interface state densities can be reduced to values comparable to the (Al,Ga)As/GaAs interface. We have previously reported a transmission electron microscopy study indicating that ZnSe/GaAs structures exhibiting low interface state densities are associated with the formation of an interfacial layer of zinc-blende Ga2Se3. In this letter we describe a procedure whereby an interfacial layer can be deliberately introduced prior to nucleation of ZnSe. In situ x-ray photoelectron spectroscopy is used to study the nature of the bonding at the interfacial layer. A comparison of the Se 3d core level features from the ZnSe epilayer surface, a Se-reacted GaAs surface, and from a separately grown Ga2Se3 epilayer, clearly indicates the same Se bonding characteristic for the Se-reacted interfacial layer and the Ga2Se3 epilayer.

    DOI

  • CHARACTERIZATION OF GA2SE3 AT ZNSE/GAAS HETEROVALENT INTERFACES

    J QIU, DR MENKE, M KOBAYASHI, RL GUNSHOR, D LI, Y NAKAMURA, N OTSUKA

    APPLIED PHYSICS LETTERS   58 ( 24 ) 2788 - 2790  1991年06月

     概要を見る

    Despite the valence difference across the junction, it has been shown that ZnSe/GaAs epilayer/epilayer interface state densities can be reduced to values comparable to the (Al,Ga)As/GaAs interface. We have previously reported a transmission electron microscopy study indicating that ZnSe/GaAs structures exhibiting low interface state densities are associated with the formation of an interfacial layer of zinc-blende Ga2Se3. In this letter we describe a procedure whereby an interfacial layer can be deliberately introduced prior to nucleation of ZnSe. In situ x-ray photoelectron spectroscopy is used to study the nature of the bonding at the interfacial layer. A comparison of the Se 3d core level features from the ZnSe epilayer surface, a Se-reacted GaAs surface, and from a separately grown Ga2Se3 epilayer, clearly indicates the same Se bonding characteristic for the Se-reacted interfacial layer and the Ga2Se3 epilayer.

    DOI

  • CHARACTERIZATION OF GA2SE3 AT ZNSE/GAAS HETEROVALENT INTERFACES

    J QIU, DR MENKE, M KOBAYASHI, RL GUNSHOR, D LI, Y NAKAMURA, N OTSUKA

    APPLIED PHYSICS LETTERS   58 ( 24 ) 2788 - 2790  1991年06月

     概要を見る

    Despite the valence difference across the junction, it has been shown that ZnSe/GaAs epilayer/epilayer interface state densities can be reduced to values comparable to the (Al,Ga)As/GaAs interface. We have previously reported a transmission electron microscopy study indicating that ZnSe/GaAs structures exhibiting low interface state densities are associated with the formation of an interfacial layer of zinc-blende Ga2Se3. In this letter we describe a procedure whereby an interfacial layer can be deliberately introduced prior to nucleation of ZnSe. In situ x-ray photoelectron spectroscopy is used to study the nature of the bonding at the interfacial layer. A comparison of the Se 3d core level features from the ZnSe epilayer surface, a Se-reacted GaAs surface, and from a separately grown Ga2Se3 epilayer, clearly indicates the same Se bonding characteristic for the Se-reacted interfacial layer and the Ga2Se3 epilayer.

    DOI J-GLOBAL

  • RECONSTRUCTION STRUCTURE AT GA2SE3/GAAS EPITAXIAL INTERFACE

    D LI, Y NAKAMURA, N OTSUKA, J QIU, M KOBAYASHI, RL GUNSHOR

    JOURNAL OF CRYSTAL GROWTH   111 ( 1-4 ) 1038 - 1042  1991年05月  [査読有り]

     概要を見る

    A highly developed reconstruction structure was found at the Ga2Se3/GaAs epitaxial interface by transmission electron microscope observations. The atomic structure of the reconstruction was derived by the analysis of electron diffraction patterns and high resolution transmission electron microscope images. The structure, which is described as an ordered arrangement of structural vacancies on the Ga sublattice, suggests that the reconstruction results from the valence mismatch at the Ga2Se3/GaAs interface.

    DOI

  • QUANTUM-WELLS WITH ZINCBLENDE MNTE BARRIERS

    J HAN, SM DURBIN, RL GUNSHOR, M KOBAYASHI, DR MENKE, N PELEKANOS, M HAGEROTT, AV NURMIKKO, Y NAKAMURA, N OTSUKA

    JOURNAL OF CRYSTAL GROWTH   111 ( 1-4 ) 767 - 771  1991年05月  [査読有り]

     概要を見る

    In this paper we describe a series of MnTe/CdTe/MnTe and MnTe/InSb/MnTe single quantum well structures. For the CdTe quantum wells we report the observation of luminescence covering the entire visible range from red to blue; a quantized state in the InSb well is used to implement resonant tunneling. X-ray diffraction and transmission electron microscopy (TEM) were used to evaluate the microstructural quality of the structures. Dark-field TEM showed that, in spite of the 2.3% lattice mismatch, the MnTe layers remained pseudomorphic and dislocation-free. High resolution images (also used to determine dimensional details) indicated that the interfaces were atomically abrupt, and that the CdTe and InSb wells were essentially unstrained in each of the structures; most of the strain was contained in the MnTe barrier layers. Optical properties of the single quantum well structures have been studied using photoluminescence and photoluminescence excitation spectroscopy. Blue luminescence at 2.59 eV (n = 1 transition) has been observed from a structure with a 10 angstrom CdTe well. The negative differential resistance observed from MnTe/InSb resonant tunneling structures represents, to our knowledge, the first report of a dimensionally quantized state in InSb.

    DOI

  • ZNSE/GAAS HETEROVALENT INTERFACES - INTERFACE MICROSTRUCTURE VERSUS ELECTRICAL-PROPERTIES

    J QIU, DR MENKE, M KOBAYASHI, RL GUNSHOR, QD QIAN, D LI, N OTSUKA

    JOURNAL OF CRYSTAL GROWTH   111 ( 1-4 ) 747 - 751  1991年05月

     概要を見る

    Epitaxial ZnSe/epitaxial GaAs interfaces are formed by molecular beam epitaxy and evaluated by several techniques including capacitance-voltage (C-V) measurements. The GaAs surface stoichiometry is systematically varied prior to the nucleation of ZnSe. A dramatic reduction of interface state density occurred when the GaAs epilayer is made As deficient. The ZnSe/GaAs interfaces exhibiting low interface state densities are associated with the presence of an interfacial layer of zincblende Ga2Se3. In situ X-ray photoelectron spectroscopy (XPS) is used to study the nature of the bonding at the interfacial layer. The character of Se 3d core level features from the interfacial region and from separately grown Ga2Se3 epilayers support the identification of the interfacial layer as Ga2Se3.

    J-GLOBAL

  • III-VI Interfacial Compounds

    M. Kobayashi, D.R. Menke, R.L. Gunshor

    Proc. of IEEE/LEOS Summer Topical Meeting on Epitaxial Materials and In-situ Processing for Optoelectronic Devices     51 - 52  1991年  [査読有り]

  • INTERFACE PROPERTIES OF HETEROVALENT INSB MULTILAYER STRUCTURES

    M KOBAYASHI, RL GUNSHOR, JL GLENN, S O, J HAN, DR MENKE, LA KOLODZIEJSKI, D LI, N OTSUKA

    LONG-WAVELENGTH SEMICONDUCTOR DEVICES, MATERIALS, AND PROCESSES   216   227 - 232  1991年  [査読有り]

  • OPTICAL-PROPERTIES OF MBE-GROWN ZNTE EPILAYERS

    G KUDLEK, N PRESSER, J GUTOWSKI, DL MATHINE, M KOBAYASHI, RL GUNSHOR

    PHYSICAL CONCEPTS OF MATERIALS FOR NOVEL OPTOELECTRONIC DEVICE APPLICATIONS I : MATERIALS GROWTH AND CHARACTERIZATION, PTS 1 AND 2   1361   150 - 158  1991年  [査読有り]

  • NONLINEAR TRANSMISSION OF MBE-GROWN ZNSE EPILAYERS IN THE NEAR-BAND-EDGE REGION

    N PRESSER, G KUDLEK, J GUTOWSKI, DR MENKE, M KOBAYASHI, RL GUNSHOR

    SUPERLATTICES AND MICROSTRUCTURES   10 ( 2 ) 247 - 252  1991年  [査読有り]

    DOI

  • INTERFACE PROPERTIES OF II-VI III-V HETEROSTRUCTURES

    RL GUNSHOR, M KOBAYASHI, N OTSUKA

    HETEROEPITAXY OF DISSIMILAR MATERIALS   221   303 - 310  1991年  [査読有り]

  • COMPARATIVE OPTICAL INVESTIGATIONS OF ZNSE GAAS EPILAYERS GROWN BY MOLECULAR-BEAM AND HOT-WALL EPITAXY

    G KUDLEK, N PRESSER, J GUTOWSKI, K HINGERL, H SITTER, SM DURBIN, DR MENKE, M KOBAYASHI, RL GUNSHOR

    JOURNAL OF APPLIED PHYSICS   68 ( 11 ) 5630 - 5635  1990年12月

     概要を見る

    Comparative photoluminescence and excitation spectra of ZnSe/GaAs epilayers grown by molecular beam epitaxy (MBE) and hot-wall epitaxy (HWE) show likewise features in the exciton energy regime. Two strain-split components of the free exciton are observed, as well as characteristic sets of transitions from or into ground and excited states of acceptor- and donor-bound excitons. However, all respective lines are shifted to lower energies in the HWE samples, due to the increased thermally induced strain as a consequence of the substrate temperatures being enhanced compared to the MBE growth. Whereas the dominant donors are of the same nature in both kinds of samples, specific acceptor centers are incorporated in the HWE films. Although the MBE-grown layers are of superior quality, it is shown that HWE under optimized growth conditions is a cheap and useful alternative to obtain ZnSe epilayers of reliable properties.

    DOI

  • Radiative recombination in CdTe/MnTe quantum wells: Emission from near infrared to blue wavelengths

    Q. Fu, N. Pelekanos, Arto V. Nurmikko, S. Durbin, J. Han, M. Kobayashi, R. L. Gunshor

    XVII International Conference on Quantum Electronics. Digest of     60 - 61  1990年12月

     概要を見る

    A series of strained single-quantum-well (SQW) CdTe/MnTe structures with well thicknesses ranging from approximately 50 to 10 angstrom were studied. Raman experiments indicate that the lattice mismatch of approximately 3.2% is coherently accommodated if the MnTe barrier layers remain sufficiently thin (typically approximately 40 angstrom). As an example of the effects of the strong quantum confinement in these heterostructures, photoluminescence spectra (normalized amplitudes) obtained from three CdTe quantum-well samples with well thickness of approximately 22, 15, and 10 angstrom, respectively, are shown. The emissions occur in the red, yellow, and blue for the n = 1 exciton recombination in the structures. The blue emission (at approximately 478 nm) shows how confinement effects are responsible for increasing the optical gap of CdTe by approximately 1 eV. Steady-state and transient spectroscopy were applied to the quantum wells to detail the confined electronic states. An approximate conduction-to-valence band offset ratio of approximately 10:1 and excitonic binding energies in the range of 20-25 meV were inferred. Temperature-dependent linewidth studies gave a measure of the exciton-optical phonon coupling strengths that was a factor of approximately 5-8 larger than values reported for the GaAs quantum wells.

  • ULTRAVIOLET AND BLUE HOLOGRAPHIC LITHOGRAPHY OF ZNSE EPILAYERS AND HETEROSTRUCTURES WITH FEATURE SIZE TO 100 NM AND BELOW

    W WALECKI, WR PATTERSON, AV NURMIKKO, H LUO, N SAMARTH, JK FURDYNA, M KOBAYASHI, S DURBIN, RL GUNSHOR

    APPLIED PHYSICS LETTERS   57 ( 25 ) 2641 - 2643  1990年12月

     概要を見る

    We have employed short-wavelength holographic laser lithography and reactive ion etching to define wire and dot-like patterns in ZnSe thin epitaxial films and heterostructures with spatial feature size to better than 100 nm. Photoluminescence measurements suggest that surface damage from etching may be much less severe than in III-V semiconductors.&lt;hedend&gt;.

    DOI

  • Thermally induced optical bistability in ZnSe epilayers grown by molecular-beam epitaxy

    G. Kudlek, J. Hollandt, N. Presser, J. Gutowski, S. M. Durbin, D. R. Menke, M. Kobayashi, R. L. Gunshor

    Journal of Applied Physics   68   2532 - 2534  1990年12月

     概要を見る

    For the first time, ZnSe epitaxial layers grown by molecular-beam epitaxy are shown to exhibit large contrast, low power, and extremely long-term stable thermally induced absorptive optical bistability. It is observed over a wide temperature range between 169 K and RT, with a strongly variable loop width and a switch-back adjustable to be less than 50% of the respective switch-down value. Critical slowing down as well as switch-down times are studied in dependence of the excess over the switch-down intensity values.

    DOI

  • Structure of the ZnSe/GaAs heteroepitaxial interface

    D. Li, J. M. Gonsalves, N. Otsuka, J. Qiu, M. Kobayashi, R. L. Gunshor

    Applied Physics Letters   57   449 - 451  1990年12月

     概要を見る

    Interfaces of pseudomorphic (100) ZnSe/GaAs heterostructures grown by molecular beam epitaxy have been studied by transmission electron microscopy. The observation of three different heterostructures suggests the existence of a transition structure at the ZnSe/GaAs interfaces which have formed on As-deficient GaAs surfaces. The transition structure appears as a bright line in dark field images of the 200 reflection, while it becomes a dark line in dark field images of the 400 reflection. These observations are explained by assuming the existence of an interface layer which has a zinc blende type structure having vacancies in one of the face centered cubic sublattices.

    DOI

  • Influence of GaAs surface stoichiometry on the interface state density of as-grown epitaxial ZnSe/epitaxial GaAs heterostructures

    J. Qiu, Q. D. Qian, R. L. Gunshor, M. Kobayashi, D. R. Menke, D. Li, N. Otsuka

    Applied Physics Letters   56   1272 - 1274  1990年12月

     概要を見る

    Epitaxial ZnSe/epitaxial GaAs interfaces have been formed by molecular beam expitaxy and evaluated by several techniques including capacitance-voltage measurements. In the study reported here, the GaAs surface stoichiometry was systematically varied prior to the nucleation of ZnSe. A dramatic reduction of interface state density occurred when the GaAs epilayer was made As deficient. The resulting interface state densities of as-grown structures are comparable to values obtained with (Al,Ga)As/GaAs interfaces.

    DOI

  • EFFECT OF GAAS SURFACE RECONSTRUCTION ON INTERFACE STATE DENSITY OF EPITAXIAL ZNSE EPITAXIAL GAAS HETEROSTRUCTURES

    J QIU, QD QIAN, M KOBAYASHI, RL GUNSHOR, DR MENKE, D LI, N OTSUKA

    JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B   8 ( 4 ) 701 - 704  1990年07月  [査読有り]

  • SPECTROSCOPY OF CDTE/MNTE SINGLE QUANTUM-WELLS - A STRAINED-LAYER II-VI HETEROSTRUCTURE WITH STRONG ELECTRONIC CONFINEMENT

    N PELEKANOS, Q FU, J DING, W WALECKI, AV NURMIKKO, SM DURBIN, J HAN, M KOBAYASHI, RL GUNSHOR

    PHYSICAL REVIEW B   41 ( 14 ) 9966 - 9970  1990年05月

     概要を見る

    A range of optical studies has been carried out on a series of single quantum wells of CdTe/MnTe. The structures appear to be nearly pseudomorphic and show evidence for very effective electron-hole confinement. For thin quantum-well layers, efficient low-temperature photoluminescence up to yellow-green photon energies has been obtained. Coupling of excitons to longitudinal-optical phonons has also been measured. © 1990 The American Physical Society.

    DOI

  • Influence of GaAs Surface Stoichiometry on the Electrical Properties of as-grown Epitaxial ZnSe/epitaxial GaAs Heterointerfaces

    J. Qiu, Q.D. Qian, R.L. Gunshor, M. Kobayashi, D.R. Menke, D. Li, N. Otsuka

    Journal of Vacuum Science and Technology B: Nanotechnology and Microelectronics   8 ( 4 ) 701 - 704  1990年04月  [査読有り]

  • SPECTROSCOPY IN CDTE/MNTE AND ZNTE/MNTE SINGLE QUANTUM-WELLS - NEW BINARY WIDE GAP II-VI HETEROSTRUCTURES

    N PELEKANOS, Q FU, AV NURMIKKO, S DURBIN, J HAN, O SUNGKI, D MENKE, M KOBAYASHI, RL GUNSHOR

    JOURNAL OF CRYSTAL GROWTH   101 ( 1-4 ) 628 - 631  1990年04月  [査読有り]

  • HIGH-DENSITY LUMINESCENCE AND EXCITATION SPECTROSCOPY OF MBE-GROWN ZNSE/GAAS EPILAYERS

    G KUDLEK, N PRESSER, J GUTOWSKI, S DURBIN, D MENKE, M KOBAYASHI, RL GUNSHOR

    JOURNAL OF CRYSTAL GROWTH   101 ( 1-4 ) 667 - 672  1990年04月

     概要を見る

    MBE-grown ZnSe epilayers on (100) GaAs substrates are optically investigated under moderate to high excitation densities. Below the light-hole and heavy-hole exciton lines Xlhand Xhh, two lines I2and I&#039;2are dominant in the luminescence spectra which are related to transitions from a neutral-donor-exciton complex (D0, X). For the first time, comparative excitation spectroscopy and magnetooptics of bound excitons in ZnSe epilayers allowed to determine their term structure, g-values and diamagnetic shifts. In the excitation spectra of the I2line, a set of resonances located 1.2 meV to 2.9 meV on its high-energy side can be interpreted as specific transitions into excited states of the neutral-donor-exciton complex. For excitation densities until 50 kW/cm2, high-excitation bands appear, superimposing the exciton luminescence. They are discussed to be due to exciton-exciton collision processes and can be compared with high-density transitions known from bulk ZnSe crystals. © 1989.

    DOI

  • ZNTE MNTE - A NEW METASTABLE WIDE GAP II-VI HETEROSTRUCTURE

    S DURBIN, M KOBAYASHI, Q FU, N PELEKANOS, RL GUNSHOR, AV NURMIKKO

    SURFACE SCIENCE   228 ( 1-3 ) 33 - 36  1990年04月

     概要を見る

    Optical characteristics of a new metastable wide-gap II-VI semiconductor heterostructure ZnTe/MnTe are reported. Single ZnTe/MnTe quantum wells show strong n = 1 exciton resonance manifesting, for example, in pronounced enhancement of the Raman cross-section. Pseudomorphic nature of the structures is inferred from strain induced shifts in the optical phonon spectrum. © 1990.

    DOI

  • TRANSMISSION ELECTRON-MICROSCOPE STUDY OF II-VI/III-V SEMICONDUCTOR INTERFACES

    N OTSUKA, D LI, JM GONSALVES, C CHOI, M KOBAYASHI, LA KOLODZIEJSKI, RL GUNSHOR

    SURFACE SCIENCE   228 ( 1-3 ) 96 - 101  1990年04月

     概要を見る

    Structures of ZnSe/GaAs epitaxial interfaces have been studied by cross-sectional transmission electron microscopy. Narrow dark bands are observed along these interfaces in their bright field and high resolution electron microscope images, suggesting a certain form of modifications of the structure. Despite the appearance of the dark hands, perfect coherent lattice structures are observed in high resolution images of the interfaces. Weak beam dark field images indicate the presence of lattice distortions in the neighborhood of the interfaces. These observations are explained by assuming the existence of a thin interface layer which maintain the coherent lattice relation with matrix crystals. As-grown and annealed ZnSe/GaAs epitaxial interfaces are compared in order to investigate the structural origin of the change of the electrical property of the interface by the post-growth annealing. The observation suggests that the interfacial layer remains after annealing but has changed into a slightly broader one. © 1990.

    DOI

  • MOLECULAR-BEAM EPITAXY OF PSEUDOMORPHIC ZNTE ALSB GASB

    DL MATHINE, SM DURBIN, RL GUNSHOR, M KOBAYASHI, DR MENKE, J GONSALVES, N OTSUKA, Q FU, M HAGEROTT, AV NURMIKKO

    SURFACE SCIENCE   228 ( 1-3 ) 344 - 346  1990年04月

     概要を見る

    The difficulty in achieving the amphoteric doping of wide gap II-VI semiconductors for use in light emitting devices suggests the merits of heterojunction injection. This paper discusses the first epilayer/epilayer ZnTe/AlSb/GaSb heterojunctions grown by MBE. Pseudomorphic ZnTe layers were nucleated on pseudomorphic AlSb layers; the AlSb was grown on homoepitaxial GaSb buffer layers. Free exciton related features were observed in the photoluminescence of ZnTe; dominant features of the PL corresponded to near band-edge transitions. Microstructural quality was examined using TEM and X-ray rocking curves. Cross-sectional TEM images reveal atomically flat interfaces. X-ray rocking curve full width at half maximum values were close to the theoretically expected broadening due to the finite layer thickness. © 1990.

    DOI

  • WIDE-GAP II-VI HETEROSTRUCTURES

    RL GUNSHOR, AV NURMIKKO, LA KOLODZIEJSKI, M KOBAYASHI, N OTSUKA

    JOURNAL OF CRYSTAL GROWTH   101 ( 1-4 ) 14 - 22  1990年04月

     概要を見る

    New advances in epitaxial growth techniques have contributed to an improved understanding of the properties of II-VI materials and their alloys. The creation of novel heterojunctions, quantum well structures, and strained-layer superlattices, composed of II-VI/III-V and II-VI/II-VI multilayers, can be attributed to their successful epitaxial growth by molecular beam epitaxy (MBE). The objective of this paper is to discuss some recent advances in the growth of II-VI/III-V and II-VI/II-VI heterostructures, with emphasis on two particular topics. In the first, pseudomorphic epilayer/epilayer heterojunctions consisting of ZnTe on AlSb, a configuration with potential for the development of injection light emitting devices, have been grown by MBE. Microstructural and optical evaluation has indicated a high structural quality. The second topic describes the use of MBE for the growth of novel structures incorporating a previously hypothetical magnetic semiconductor, the zincblende phase of MnTe. Characterization using TEM and X-ray diffraction reveals only the zincblende phases of MnTe. Whereas bulk crystals of MnTe having a NiAs structure with a bandgap of 1.3 eV, the zincblende phase exhibits a bandgap of 3.2 eV. Single quantum well structures incorporating zincblende MnTe exhibit 2D electron and hole confinement in both CdTe and ZnTe quantum wells, and serve to confirm the zincblende MnTe bandgap at 3.2 eV. © 1989.

    DOI

  • SPECTROSCOPY IN CDTE/MNTE AND ZNTE/MNTE SINGLE QUANTUM-WELLS - NEW BINARY WIDE GAP II-VI HETEROSTRUCTURES

    N PELEKANOS, Q FU, AV NURMIKKO, S DURBIN, J HAN, O SUNGKI, D MENKE, M KOBAYASHI, RL GUNSHOR

    JOURNAL OF CRYSTAL GROWTH   101 ( 1-4 ) 628 - 631  1990年04月

     概要を見る

    With the incorporation of cubic zincblende MnTe, a range of optical studies have been carried out on single quantum wells of ZnTe/MnTe and CdTe/MnTe. By using thin MnTe barrier layers the structures appear to be nearly pseudomorphic and show evidence for good electron-hole confinement. © 1989.

    DOI

  • STRONG CONFINEMENT EFFECTS IN CDTE/MNTE QUANTUM-WELLS - A NEW STRAINED LAYER BINARY-II-VI HETEROSTRUCTURE

    Q FU, N PELEKANOS, AV NURMIKKO, S DURBIN, J HAN, O SUNGKI, D MENKE, M KOBAYASHI, RL GUNSHOR

    SURFACE SCIENCE   229 ( 1-3 ) 148 - 150  1990年04月

     概要を見る

    A range of optical studies have been carried out on a series of single quantum wells of CdTe/MnTe. The structures appear to be nearly pseudomorphic and show evidence for robust electron-hole confinement. Exciton states have been characterized in terms of lifetime and coupling to optical phonons. © 1990.

    DOI

  • HOT EXCITON LUMINESCENCE IN ZNTE-MNTE QUANTUM-WELLS

    N PELEKANOS, J DING, Q FU, AV NURMIKKO, SM DURBIN, M KOBAYASHI, RL GUNSHOR

    20TH INTERNATIONAL CONFERENCE ON THE PHYSICS OF SEMICONDUCTORS, VOLS 1-3     2518 - 2521  1990年  [査読有り]

  • TRANSMISSION ELECTRON-MICROSCOPY OF II-VI III-V SEMICONDUCTOR HETEROEPITAXIAL INTERFACES

    D LI, N OTSUKA, J QIU, J GLENN, M KOBAYASHI, RL GUNSHOR

    PROPERTIES OF II-VI SEMICONDUCTORS : BULK CRYSTALS, EPITAXIAL FILMS, QUANTUM WELL STRUCTURES, AND DILUTE MAGNETIC SYSTEMS   161   127 - 132  1990年  [査読有り]

  • EFFECT OF GAAS SURFACE STOICHIOMETRY ON THE INTERFACE OF AS-GROWN EPITAXIAL ZNSE EPITAXIAL GAAS HETEROSTRUCTURES

    J QIU, RL GUNSHOR, M KOBAYASHI, DR MENKE, QD QIAN, D LI, N OTSUKA

    PROPERTIES OF II-VI SEMICONDUCTORS : BULK CRYSTALS, EPITAXIAL FILMS, QUANTUM WELL STRUCTURES, AND DILUTE MAGNETIC SYSTEMS   161   115 - 119  1990年  [査読有り]

  • PSEUDOMORPHIC ZNTE/ALSB/GASB HETEROSTRUCTURES BY MOLECULAR-BEAM EPITAXY

    DL MATHINE, J HAN, M KOBAYASHI, RL GUNSHOR, DR MENKE, M VAZIRI, J GONSALVES, N OTSUKA, Q FU, M HAGEROTT, AV NURMIKKO

    PROPERTIES OF II-VI SEMICONDUCTORS : BULK CRYSTALS, EPITAXIAL FILMS, QUANTUM WELL STRUCTURES, AND DILUTE MAGNETIC SYSTEMS   161   121 - 125  1990年  [査読有り]

  • Recent Advances in Strained Wide-Gap II-VI Semiconductor Superlattices

    A.V. Nurmikko, R.L. Gunshor, M. Kobayashi, L.A. Kolodziejski

      161  1990年  [査読有り]  [招待有り]

  • LOW INTERFACE STATE DENSITIES IN AS-GROWN EPITAXIAL ZNSE EPITAXIAL GAAS HETEROSTRUCTURES

    J QIU, QD QIAN, M KOBAYASHI, RL GUNSHOR, DR MENKE, D LI, N OTSUKA, LA KOLODZIEJSKI

    GALLIUM ARSENIDE AND RELATED COMPOUNDS 1989   106   201 - 206  1990年  [査読有り]

  • LONG-TERM STABLE THERMALLY INDUCED ABSORPTIVE OPTICAL BISTABILITY IN MBE-GROWN ZNSE EPILAYERS

    G KUDLEK, J HOLLANDT, N PRESSER, J GUTOWSKI, DR MENKE, M KOBAYASHI, RL GUNSHOR

    SUPERLATTICES AND MICROSTRUCTURES   8 ( 4 ) 381 - 385  1990年

     概要を見る

    MBE-grown ZnSe epilayers released from their GaAs substrates exhibit thermally induced absorptive optical bistability of high contrast ratios and low switching powers in a wide temperature range up to room temperature. For increasing sample thickness or for enhanced reflection realized by inserting the samples into a resonator, counteracting dispersive switching becomes visible. The interplay of both the absorptive and dispersive effects is studied for different samples and varied experimental parameters. Long-term stability of the samples with regard to all switching effects makes them promising candidates for application studies. © 1990.

    DOI

  • Atomic Structure of Heteroepitaxial Interface between II-VI and III-V Semiconductor

    N. Otsuka, D. Li, J. Qiu, M. Kobayashi, R. L. Gunshor

    Materials Transactions, JIM   31   622 - 627  1990年01月

     概要を見る

    A series of pseudomorphic (100) ZnSe/GaAs heterostructures were grown by molecular beam epitaxy on GaAs epilayers which had different As coverages of surfaces. A large variation of the interface state density was observed among the heterostructures by capacitance-voltage measurements. Transmission electron microscope observations of cross-sectional samples have revealed existence of an interface layer in the heterostructures grown on As-deficient GaAs surfaces. Analyses of dark field images and high resolution microscope images have shown that the interface layer has a structure similar to that of Ga2Se3which crystallizes in a zincblende type structure with vacancies on the Ga sublattice. © 1990, The Japan Institute of Metals. All rights reserved.

    DOI

  • High‐Density Spectroscopy of ZnSe/GaAs Epilayers in the Near‐Band‐Edge Region

    N. Presser, G. Kudlek, J. Gutowski, S. M. Durbin, D. R. Menke, M. Kobayashi, R. L. Gunshor

    physica status solidi (b)   159   443 - 448  1990年01月

     概要を見る

    ZnSe epilayers grown by MBE on (100) GaAs substrates are optically investigated in comparison with bulk ZnSe crystals using photoluminescence and excitation spectroscopy under high excitation densities. High‐density luminescence bands appear in both materials for relatively low excitation densities (about 30 kW/cm2), but their energetic positions do not correspond. The intensity‐dependent shape, and the behaviour of the dominant band in bulk ZnSe in excitation spectroscopy are similar to that of the M band in other II VI semiconductors. The main bands growing up in the ZnSe/GaAs films are much more corresponding to typical P‐band emission of exciton‐exciton collision. Further, the transmission of ZnSe epilayers released from the GaAs substrate is studied in dependence on the laser intensity. Copyright © 1990 WILEY‐VCH Verlag GmbH &amp; Co. KGaA

    DOI

  • MBE OF WIDE BANDGAP II-VI COMPOUNDS

    RL GUNSHOR, M KOBAYASHI, LA KOLODZIEJSKI, N OTSUKA, AV NURMIKKO

    JOURNAL OF CRYSTAL GROWTH   99 ( 1-4 ) 390 - 398  1990年01月

     概要を見る

    A pseudomorphic epilayer/epilayer heterojunction consisting of ZnTe on AlSb, having potential for the development of novel visible light emitting injection devices, has been grown by MBE. A variety of microstructural and optical evaluation techniques have provided evidence of high structural quality. The nonequilibrium growth capability of the MBE technique has enabled the growth of heterostructures incorporating a previously hypothetical widegap magnetic semiconductor, the zincblende phase of MnTe. Electron diffraction measurements of cross-sectional samples reveal only zincblende phases. Double barrier structures incorporating zincblende MnTe are found to exhibit 2D electron and hole confinement in CdTe and ZnTe quantum well layers, and serve to confirm the zincblende MnTe bandgap at 3.2 eV. © 1990.

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  • ZnSe-ZnTe strained-layer superlattices: A novel material for the future optoelectronic devices

    Makoto Konagai, Masakazu Kobayashi, Ryuhei Kimura, Kiyoshi Takahashi

    Journal of Crystal Growth   86 ( 1-4 ) 290 - 295  1990年01月

     概要を見る

    ZnSe-ZnTe strained superlines (SLSs) were grown by molecular beam epitaxy 9MBE). Th optical properties of the ZnSe-ZnTe SLS were evaluated by photoluminescence (PL). The PL peak position was shifted by tailoring the structure of the superlattice. The luminescence color in the visible changed from blue-green to red. In order to obtain both p- and n-type conduction in wide-bandgap II-VI compound semiconductors, we have prepared ZnSe-ZnTe superlines with a modulation doping technique. When Sb was selectively doped in ZnTe layers, all the samples exhibited p-type conductivity with hole concentrations of (0.5-1.0)X1014cm-3. On the other hand, Ga-doped SLSs were type with electron concentrations of (2-7)X1013cm-3. Furthermore, the growth of ZnSe-ZnS SLS was also demostrated by metalorganic molecular beam epitaxy (MOMBE). Blue luminescence related. to the quantized levels in the SLS was detected. © 1988.

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  • HOT EXCITON LUMINESCENCE IN ZNTE-MNTE QUANTUM-WELLS

    N PELEKANOS, J DING, Q FU, AV NURMIKKO, SM DURBIN, M KOBAYASHI, RL GUNSHOR

    20TH INTERNATIONAL CONFERENCE ON THE PHYSICS OF SEMICONDUCTORS, VOLS 1-3     2518 - 2521  1990年  [査読有り]

     概要を見る

    It has been established experimentally in a number of wide-gap II-IV semiconductors, notably ZnTe, that the recombination spectrum of photon energies at and above the bandgap often consists of well-defined peaks separated by LO phonon energies. The physical issues subject to debate have been (1) the distinction between hot luminescence (HL) and resonance Raman scattering (RRS), and (2) whether the energetically relaxing electron-hole pair maintains an excitonlike character throughout the entire secondary emission process. It is shown how the availability of a ZnTe-based quantum well with advanced experimental methods gives direct insight into this problem. Experiments were carried out on a ZnTe/MnTe single-quantum-well structure with very thin MnTe barrier layers (22 angstrom). Tunneling of electron-hole pairs out of the ZnTe quantum well strongly reduces the normal thermalized PL (photoluminescence) emission, so the entire secondary emission from the quantum well is dominated by hot luminescence. The emission, ranging from the laser excitation to the region of the n = 1 excitonic bandgap, shows how the fifth-order LO-phonon-related emission is strongly resonating at this gap. Its linewidth is considerably broadened compared with the lower orders, and a rapid loss of polarization memory with increasing order is observed. To investigate the question of exciton versus hot-electron and hole character in the secondary emission, the spectra were measured in magnetic fields up to 23 T. The key point is that, apart from small spectral shifts, the main features of the spectrum are preserved, a direct indication of the exciton nature of the process of recombination.

  • HIGH-RESOLUTION MAGNETOOPTICS AND EXCITATION SPECTROSCOPY OF ULTRA-PURE MBE-GROWN ZNSE/GAAS EPILAYERS

    G KUDLEK, N PRESSER, J GUTOWSKI, DR MENKE, M KOBAYASHI, RL GUNSHOR

    20TH INTERNATIONAL CONFERENCE ON THE PHYSICS OF SEMICONDUCTORS, VOLS 1-3     1381 - 1384  1990年  [査読有り]

  • Low interface state density at an epitaxial ZnSe/epitaxial GaAs interface

    Q. D. Qian, J. Qiu, M. R. Melloch, J. A. Cooper, L. A. Kolodziejski, M. Kobayashi, R. L. Gunshor

    Applied Physics Letters   54   1359 - 1361  1989年12月

     概要を見る

    The capacitance-voltage (C-V) and the current-voltage characteristics of metal/ZnSe/p-GaAs capacitors have been investigated; both epitaxial layers were grown by molecular beam epitaxy. In the capacitor structures highly resistive, stoichiometric ZnSe functioned as the pseudoinsulator on the doped GaAs layers. The capacitance-voltage measurements demonstrated that the capacitors could be biased from accumulation through depletion, and into deep depletion, with current in the range of 10-8A cm-2. Very little frequency dispersion was observed in the C-V data when measured from 1 kHz to 1 MHz. From the high-frequency C-V curve, the surface state density as a function of position in the GaAs band gap was determined. Surface state densities were comparable to densities reported for (Al,Ga)As/GaAs heterojunctions.

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  • Zinc-blende MnTe: Epilayers and quantum well structures

    S. M. Durbin, J. Han, O. Sungki, M. Kobayashi, D. R. Menke, R. L. Gunshor, Q. Fu, N. Pelekanos, A. V. Nurmikko, D. Li, J. Gonsalves, N. Otsuka

    Applied Physics Letters   55   2087 - 2089  1989年12月

     概要を見る

    Epilayers of the previously hypothetical zinc-blende MnTe have been grown by molecular beam epitaxy. Epitaxial layers (0.5 μm thick) of MnTe were characterized using x-ray diffraction and transmission electron microscopy; optical reflectance measurements indicate a band gap of ∼3.2 eV. A series of strained single quantum well structures was fabricated with zinc-blende MnTe forming the barrier to CdTe quantum well regions; photoluminescence spectra indicate optical transitions corresponding to strong electron and hole confinement.

    DOI

  • Deep levels in Ga-doped ZnSe grown by molecular-beam epitaxy

    S. Venkatesan, R. F. Pierret, J. Qiu, M. Kobayashi, R. L. Gunshor, L. A. Kolodziejski

    Journal of Applied Physics   66   3656 - 3660  1989年12月

     概要を見る

    Results of a deep-level transient spectroscopy study of Ga-doped ZnSe thin films grown by molecular-beam epitaxy are presented. Two prominent deep levels were observed in all the samples investigated. The concentration of the trap detected at 0.34 eV below the conduction-band edge was essentially independent of the doping concentration and is attributed to native defects arising from Se vacancies in the ZnSe films. The second level with an activation energy of 0.26 eV shows a very strong doping dependence and is tentatively identified as arising from dopant-site (gallium-on-zinc-site) defects complexed with selenium vacancies. Preliminary results also indicate that planar doping of ZnSe significantly reduces the concentration of the Ga-vacancy complex.

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  • ELECTRICAL CHARACTERIZATION OF AN EPITAXIAL ZNSE EPITAXIAL GAAS HETEROINTERFACE

    QD QIAN, J QIU, M KOBAYASHI, RL GUNSHOR, MR MELLOCH, JA COOPER

    JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B   7 ( 4 ) 793 - 798  1989年07月  [査読有り]

    DOI

  • PSEUDOMORPHIC ZNTE ALSB GASB HETEROSTRUCTURES BY MOLECULAR-BEAM EPITAXY

    DL MATHINE, SM DURBIN, RL GUNSHOR, M KOBAYASHI, DR MENKE, Z PEI, J GONSALVES, N OTSUKA, Q FU, M HAGEROTT, AV NURMIKKO

    APPLIED PHYSICS LETTERS   55 ( 3 ) 268 - 270  1989年07月

     概要を見る

    A series of pseudomorphic ZnTe/AlSb/GaSb epilayer/epilayer heterostructures, aimed at the realization of novel wide band-gap light-emitting devices, was grown by molecular beam epitaxy. The structures were evaluated by several techniques including transmission electron microscopy (TEM), x-ray rocking curves, photoluminescence (PL), and Raman spectroscopy. Reflection high-energy electron diffraction intensity oscillations were observed during nucleation of ZnTe. The presence of dislocation-free pseudomorphic structures was confirmed by TEM. The PL spectra of ZnTe epilayers showed dominant near-band-edge features composed of free and shallow impurity bound excitons.

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  • II-VI/III-V heterostructures: Epilayer-on-epilayer structures

    R. L. Gunshor, L. A. Kolodziejski, M. Kobayashi, N. Otsuka, A. V. Nurmikko

    Proceedings of SPIE - The International Society for Optical Engineering   1037   78 - 85  1989年03月

     概要を見る

    The molecular beam epitaxy (MBE) and the microstructural, optical, and electrical characterization of two technologically important heterojunctions, the CdTe/InSb and the ZnSe/GaAs, are described. The II-VI/III-V heterointerface is formed by the epitaxial growth of each layer in either separate MBE growth chambers, or by each layer growth occurring in a single growth chamber. For the case where separate growth chambers are used, the active interface is preserved by employing passivation techniques, or by transferring the sample between growth chambers in an ultrahigh vacuum transfer module. The aforementioned growth approaches allow for the formation of an ‘epitaxial’ heterojunction, to be utilized as an active part of a heterojunction device. The CdTe/InSb heterointerface is approximately lattice matched (&lt;0.05% mismatch), and is motivated by possible device applications provided by InSb quantum wells. The low temperature growth of InSb quantum wells is achieved by the use of an antimony cracking oven to provide Sb2molecules for the growth. No clear indication of mixed interfacial layers of In2Te3is observed by Raman spectroscopy or transmission electron microscopy. The ZnSe/GaAs heterointerface, having a 0.25% lattice constant mismatch, has potential for use in passivation of GaAs devices. The highly resistive, stoichiometric ZnSe is employed as an insulator in two GaAs device configurations: a field effect transistor structure and a metal-insulator-semiconductor capacitor. Electrical characteristics of the ZnSe/GaAs interface provide evidence of the electrical integrity, with measurements of the interface state density resulting in numbers comparable to those reported for the (A1, Ga)As/GaAs interface. © 1989, SPIE.

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  • MOLECULAR-BEAM EPITAXY OF INSB/CDTE HETEROSTRUCTURES

    JL GLENN, S O, LA KOLODZIEJSKI, RL GUNSHOR, M KOBAYASHI, D LI, N OTSUKA, M HAGGEROTT, N PELEKANOS, AV NURMIKKO

    JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B   7 ( 2 ) 249 - 252  1989年03月  [査読有り]

    DOI

  • II-VI/III-V HETEROINTERFACES - EPILAYER-ON-EPILAYER STRUCTURES

    QD QIAN, J QIU, JL GLENN, O SUNGKI, RL GUNSHOR, LA KOLODZIEJSKI, M KOBAYASHI, N OTSUKA, MR MELLOCH, JA COOPER, M HAGGEROTT, T HEYEN, AV NURMIKKO

    JOURNAL OF CRYSTAL GROWTH   95 ( 1-4 ) 567 - 571  1989年02月

     概要を見る

    The integration of several optoelectronic device functions onto a common substrate material is an area which is currently being actively pursued. In an effort to achieve this objective, experiments are under way to examine the epitaxial growth and material properties of a variety of both II-VI and III-V compounds grown on a substrate where the II-VI/III-V heterostructure can be utilized. This paper describes some recent developments involving the molecular beam epitaxial (MBE) growth and characterization of two important II-VI/III-V heterostructures, CdTe/InSb and ZnSe/GaAs. The structures are formed taking three approaches, by using (i) surface passivation techniques, combined with transfer in air from one chamber to the other, (ii) separate growth chambers connected by an ultrahigh vacuum transfer module, and (iii) both III-V and II-VI growth is performed in the same growth chamber. Multiple quantum wells of InSb have been grown at low temperatures of 300°C, using either Sb4or Sb2(the Sb2originates from an antimony cracker). Electrical characterization of metal/pseudomorphic ZnSe/p-GaAs capacitor structures illustrates accumulation, depletion and deep depletion; high frequency capacitance versus voltage data indicate interface state densities for the ZnSe/GaAs interface to be comparable to those reported for (Al,Ga)As/GaAs interfaces. The following paper represents a combined summary of two papers presented at the 5th International Conference on Molecular Beam Epitaxy. © 1989.

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  • Wide Gap II-VI DMS Superlattices: MBE Growth and Characterization

    R.L. Gunshor, L.A. Kolodziejski, M. Kobayashi, A.V. Nurmikko, N. Otsuka

    Mat. Res. Soc. Symp. Proc.   151   141 - 144  1989年  [査読有り]

  • LOW INTERFACE STATE DENSITY AT PSEUDOMORPHIC ZNSE EPITAXIAL GAAS INTERFACE

    QD QIAN, J QIU, M KOBAYASHI, RL GUNSHOR, LA KOLODZIEJSKI, MR MELLOCH, JA COOPER, JM GONSALVES, N OTSUKA

    III-V HETEROSTRUCTURES FOR ELECTRONIC / PHOTONIC DEVICES   145   423 - 428  1989年  [査読有り]

  • LOW INTERFACE STATE DENSITY AT THE MBE GROWN, THERMALLY ANNEALED ZNSE/GAAS INTERFACE

    QD QIAN, J QIU, MR MELLOCH, JA COOPER, RL GUNSHOR, LA KOLODZIEJSKI, M KOBAYASHI

    INSTITUTE OF PHYSICS CONFERENCE SERIES &lt;D&gt;   ( 96 ) 79 - 82  1989年  [査読有り]

     概要を見る

    The capacitance-voltage and current-voltage characteristics of metal/ZnSe/p-GaAs capacitors, where the p-GaAs and ZnSe epilayers were grown by molecular beam epitaxy, are reported. A thermal anneal process is described which reduces the ZnSe/p-GaAs interface state density to a level comparable to those reported for AlGaAs/GaAs heterojunctions.

  • KINEMATIC WAVE CHARACTERISTICS AND NEW EQUATIONS OF UNSATURATED INFILTRATION

    T YAMADA, M KOBAYASHI

    JOURNAL OF HYDROLOGY   102 ( 1-4 ) 257 - 266  1988年09月  [査読有り]

  • Electron Microscope Study of Initial Stage of Growth of ZnSe on GaAs

    J.M. Gonsalves, N. Otsuka, J. Qiu, M. Kobayashi, R.L. Gunshor, L.A. Kolodziejski

    Proc. MRS Meeting    1988年  [査読有り]

  • ELECTRICAL-PROPERTIES OF P-TYPE AND N-TYPE ZNSE-ZNTE STRAINED-LAYER SUPERLATTICES

    M KOBAYASHI, S DOSHO, A IMAI, R KIMURA, M KONAGAI, K TAKAHASHI

    SUPERLATTICES AND MICROSTRUCTURES   4 ( 2 ) 221 - 225  1988年

     概要を見る

    ZnSe and ZnTe semiconducting materials are highly promising candidates for the fabrication of short-wavelength light-emitting devices. We have grown ZnSeZnTe strained-layer superlattices (SLSs) on InP substrates by molecular beam epitaxy. In addition to undoped SLSs, two kinds of modulation doped SLS samples were prepared in this study, the first with Ga-doped ZnSe layers and undoped ZnTe layers, and the second with undoped ZnSe layers and Sb-doped ZnTe layers. Van der Pauw measurements of the SLS samples at room temperature showed that their electrical properties can be controlled by using the modulation doping technique. The undoped sample and the Ga-doped sample exhibited n-type conduction, whereas p-type conduction was observed for the Sb-doped sample. Interdiffusion profiles of dopants were measured by secondary ion mass spectroscopy, and significant Ga redistribution was observed. Finally, we have fabricated pn junctions from ZnSeZnTe SLSs, and measured their current-voltage characteristics. © 1988.

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  • Interdiffusion in ZnSe-ZnTe strained-layer superlattices

    Akira Imai, Masakazu Kobayashi, Shiro Dosho, Makoto Kongai, Kiyoshi Takahashi

    Journal of Applied Physics   64 ( 2 ) 647 - 650  1988年

     概要を見る

    A detailed study has been made of interdiffusion in ZnSe-ZnTe strained-layer superlattices (SLSs) grown by molecular-beam epitaxy (MBE) at a growth temperature of 320°C. In x-ray diffraction measurements, the satellite peak intensities relative to the zero-order peak intensity decreased with annealing time. The interdiffusion coefficient D was calculated assuming a linear diffusion model. The values of D=3.6×10- 21 to 2.2×10-19 cm2/s at an annealing temperature of 500°C were obtained for the ZnSe-ZnTe SLSs. In the high-resolution transmission electron microscopy (HRTEM) image of as-grown SLSs, the presence of fine superlattice structures was seen, but for interdiffused samples stripes due to the periodic superlattice structures were not visible and many dislocation lines were observed. These results suggest that the structure of SLSs is significantly modulated by thermal annealing at a temperature higher than the growth temperature.

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  • Doping characteristics of znse-znte strained layer superlattice grown by molecular beam epitaxy

    R. Kimura, S. Dosho, A. Imai, M. Kobayashi, M. Konagai, K. Takahashi

    Proceedings of SPIE - The International Society for Optical Engineering   792   112 - 116  1987年08月

     概要を見る

    In order to obtain both p- and n-type conduction in a wide-bandgap II-VI compound semiconductor, we have prepared ZnSe-ZnTe strained-layer superlattices (SLS) by MBE with a modulation doping technique. Modulation-doped superlattices were analyzed by photoluminescence (PL) and the van der Pauw method. The effect of strain on the film quality induced in the SLS structure by lattice mismatch was investigated. Furthermore, the SLS structure has been directly observed by Transmission Electron Microscopy (TEM). © 1987 SPIE.

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  • GROWTH AND CHARACTERIZATION OF ZNSE-ZNTE STRAINED-LAYER SUPERLATTICES

    M KOBAYASHI, R KIMURA, M KONAGAI, K TAKAHASHI

    JOURNAL OF CRYSTAL GROWTH   81 ( 1-4 ) 495 - 500  1987年02月

     概要を見る

    ZnSe-ZnTe strained-layer superlattices (SLSs) were grown on InP, GaAs and InAs substrates by molecular beam epitaxy (MBE). The samples were characterized by transmission electron microscopy (TEM) observation, and photoluminescence (PL) measurement techniques. Uniform and fine superlattice structures were confirmed by TEM observation. Moreover, a distinguishable change in the direction of (111) lattice-fringes from ZnSe layer to ZnTe layer was clearly observed in lattice image observation. The PL peak energy depended on the thickness of the alternating layers and the luminescence was related to the size quantization of the SLS structure. The luminescence peak was also affected by the substrate materials. © 1987.

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  • Realization of both p- and n-type conduction for ZnSe-ZnTe strained-layer superlattices

    Masakazu Kobayashi, Shiro Dosho, Akira Imai, Ryuhei Kimura, Makoto Konagai, Kiyoshi Takahashi

    Applied Physics Letters   51 ( 20 ) 1602 - 1604  1987年

     概要を見る

    The conduction types of ZnSe-ZnTe strained-layer superlattices (SLS's) have been controlled by using the modulation doping technique. Two kinds of modulation-doped SLS's were prepared. One of them consisted of gallium (Ga) doped ZnSe layers and undoped ZnTe layers. The other consisted of undoped ZnSe layers and antimony (Sb) doped ZnTe layers. The conduction types of the samples modulation doped with Ga and Sb were shown to be n and p type, respectively whereas the undoped samples exhibited n-type conduction. The electrical properties of the undoped and modulation-doped samples were evaluated by the van der Pauw method. The carrier concentrations of all types of samples were about 5×1013/cm3 at room temperature. The temperature dependence of the electrical properties was measured for an undoped sample and a sample modulation doped with Sb. The carrier concentrations increased with temperature and reached about 1×101 7/cm3 at 500 K.

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  • Lattice strain and lattice dynamics of ZnSe-ZnTe strained-layer superlattices

    Masakazu Kobayashi, Makoto Konagai, Kiyoshi Takahashi, Kazuyori Urabe

    Journal of Applied Physics   61 ( 3 ) 1015 - 1022  1987年

     概要を見る

    Lattice strain and lattice dynamics of ZnSe-ZnTe strained-layer superlattices (SLSs) were examined by means of transmission electron microscopy and Raman scattering. Superlattice structures were confirmed from both transmission electron diffraction patterns and bright field images of the samples. Lattice distortions which originated from misfit strains were observed by the lattice image mode. The crystallinity of the adjacent layers was degraded when the layer thickness became large and polycrystalline structures were observed when the layer thickness exceeded the critical layer thickness. Raman scattering was used to assess the magnitude of the strain in the SLSs. Optical phonon frequencies of the components in SLSs were different from those frequencies of the bulk materials. The frequency shifts were used to quantify the strains in the SLSs. The observed shifts corresponded to the calculated values.

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  • ZNSE-ZNTE STRAINED LAYER SUPERLATTICE ON INP SUBSTRATE BY MOLECULAR-BEAM EPITAXY

    M KOBAYASHI, N MINO, M KONAGAI, K TAKAHASHI

    SURFACE SCIENCE   174 ( 1-3 ) 550 - 555  1986年08月

     概要を見る

    A ZnSe-ZnTe strained layer superlattice (SLS) was grown by molecular beam epitaxy with a 7% lattice mismatch between the components of SLS. InP was used as a substrate material and there was a mismatch of only 3.5% between the components of the SLS and InP. ZnSe was expanded and ZnTe was compressed. Thus the strain was accommodated by the SLS structure and a high-quality superlattice was prepared. Reflective high-energy electron diffraction and X-ray measurements indicated that a high-quality SLS was successfully grown. The superlattice structure was also confirmed by photoluminescence (PL) measurements. Moreover, an interesting phenomenon was observed from the temperature dependence of PL intensity. Strong luminescence was obtained only at a temperature of around 60 K from several samples. © 1986.

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  • STRUCTURAL STUDY OF ZnSe-ZnTe STRAINED LAYER SUPERLATTICE ON InP SUBSTRATE PREPARED BY MBE.

    Hironori Katagiri, Masakazu Kobayashi, Naoki Mino, Kazuyori Urabe, Makoto Konagai, Kiyoshi Takahashi

    Transactions of the Institute of Electronics and Communication Engineers of Japan. Section E   E69   277 - 278  1986年04月

     概要を見る

    Direct observation of ZnSe-ZnTe strained layer superlattice was performed by transmission electron microscopy. The long periodicity of the superlattice was confirmed by the satellite spots of transmissin electron diffraction. The bright field TEM image indicated the superlattice structure without large scale misfit dislocations.

  • 半導体ひずみ超格子の最近の発展

    小林 正和, 高橋 清

    応用物理   55 ( 6 ) 595 - 600  1986年

     概要を見る

    超格子は新しい機能性材料として大きな注目をあびている.本稿では,ひずみ超格子の概念や歴史的経過,設計指針などについて述べる.また,現在までに研究・発表されている各種ひずみ超格子について,その基礎物性を紹介する.

    DOI CiNii

  • Plasma-assisted metalorganic chemical vapor deposition of ZnSe films

    Naoki Mino, Masakazu Kobayashi, Makoto Konagai, Kiyoshi Takahashi

    Journal of Applied Physics   59 ( 6 ) 2216 - 2221  1986年

     概要を見る

    ZnSe thin films were grown by plasma-assisted metalorganic chemical vapor deposition (MOCVD). Plasma-assisted MOCVD is a technique combining rf glow discharge decomposition (at 13.56 MHz) with conventional metalorganic chemical vapor deposition. This process may offer several advantages such as low-temperature growth, high chemical reactivity, cleaning effect of substrate surface, and good surface morphology. The metalorganic sources used were diethylzinc and diethylselenide. The epitaxial films were obtained at the low substrate temperature of 250 °C by plasma-assisted MOCVD. The grown films showed excellent surface morphology and uniformity over a large area. These films were applied to Al/ZnSe:Mn/ITO (indium tin oxide) dc-operated electroluminescent cells. As a manganese source, di-π-cyclopentadienyl manganese [(C5H5)2Mn] was successfully used.

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  • Photoluminescence study of ZnSe-ZnTe strained-layer superlattices grown on InP substrates

    Masakazu Kobayashi, Naoki Mino, Hironori Katagiri, Ryuhei Kimura, Makoto Konagai, Kiyoshi Takahashi

    Journal of Applied Physics   60 ( 2 ) 773 - 778  1986年

     概要を見る

    Optical properties of ZnSe-ZnTe strained-layer superlattice (SLS) grown on InP substrates were evaluated by photoluminescence. The luminescence peak intensity and position were affected by the photoexcitation intensity. The line shape was also affected by the growth temperature. The peak position was shifted by tailoring the structure of the superlattice, but it did not correlate exactly with previously reported theoretical values. We have reconsidered their data, and a better result on theoretical calulation was achieved. The luminescence color changed in the visible region from green to red. This SLS could be a new material for optoelectronic devices.

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  • Growth of a ZnSe-ZnTe strained-layer superlattice on an InP substrate by molecular beam epitaxy

    Masakazu Kobayashi, Naoki Mino, Hironori Katagiri, Ryuhei Kimura, Makoto Konagai, Kiyoshi Takahashi

    Applied Physics Letters   48 ( 4 ) 296 - 297  1986年

     概要を見る

    A ZnSe-ZnTe strained-layer superlattice (SLS) was grown on an InP substrate by molecular beam epitaxy for the first time. The x-ray diffraction measurement technique was used to confirm the existence of the high quality SLS structure. Overall quality may also be inferred from the observed quantum size effects of the photoluminescence data.

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  • ZNSE-MN DC-ELECTROLUMINESCENT CELLS USING DI-PI-CYCLOPENTADIENYL MANGANESE AS A NEW MANGANESE SOURCE FABRICATED BY PLASMA-ASSISTED MOCVD

    N MINO, M KOBAYASHI, M KONAGAI, K TAKAHASHI

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS   24 ( 5 ) L383 - L385  1985年

     概要を見る

    Al/ZnSe: Mn/ITO (indium tin oxide) dc-electroluminescent cells were fabricated by plasma-assisted organometallic chemical vapor deposition. As a new manganese source, di-lr-cyclopentadienyl manganese [(C, H), Mn] was successfully used for the first time. © 1985 IOP Publishing Ltd.

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  • MODULATION-DOPED ZNSE - MN DC THIN-FILM ELECTROLUMINESCENT DEVICES

    M KOBAYASHI, N MINO, H INUZUKA, M KONAGAI, K TAKAHASHI

    JOURNAL OF APPLIED PHYSICS   57 ( 10 ) 4706 - 4710  1985年

     概要を見る

    Two types of ZnSe:Mn dc thin-film electroluminescent (EL) devices were prepared by molecular beam growth: a Au/ZnSe:Mn/GaAs cell with a single-crystal ZnSe:Mn host layer and an Al/ZnSe:Mn/ITO cell with a polycrystal ZnSe:Mn host layer. Modulation doping was used to investigate the active region in the ZnSe:Mn layer. It was found that threshold voltage characteristics of the Au/ZnSe:Mn/GaAs cell were influenced by the Mn doping position in the ZnSe host layer, but in the Al/ZnSe:Mn/ITO cell, there was no dependence of threshold voltage on the Mn doping position. The dependence of luminescence intensity-injection current characteristics on the Mn doping position showed that the excitation probability of Mn luminescence centers by injected electrons increased in the region close to the negative electrode for both types of EL cells.

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  • EPITAXIAL-GROWTH OF HIGH-QUALITY ZNSE ON SI SUBSTRATES BY MOLECULAR-BEAM EPITAXY AND APPLICATION TO DC ELECTROLUMINESCENT CELLS

    N MINO, M KOBAYASHI, M KONAGAI, K TAKAHASHI

    JOURNAL OF APPLIED PHYSICS   58 ( 2 ) 793 - 796  1985年

     概要を見る

    ZnSe thin films were grown on (100) and (111) oriented Si substrates by molecular beam epitaxy. The single-crystalline ZnSe films were obtained in the substrate temperature range of 300-450°C. The epitaxial layers were evaluated by reflection high-energy electron diffraction, x-ray diffraction, etch pit density, photoluminescence, and Hall effect measurements. Etch pit density was estimated to be 3×105cm-2. The carrier concentration and electron mobility of the epitaxial ZnSe layers at room temperature are 1.3×1017-2.8×1017cm-3and 170-250 cm2/V s, respectively. These epitaxial films were applied to Au/ZnSe:Mn/Si dc-operated electroluminescent cells. The maximum quantum efficiency of 2.2×10-2(30.4 V, 6.3×10-5A/cm2) was achieved.

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  • EFFECTS OF INDIUM DIFFUSION ON THE PROPERTIES OF ZNSE-MN DC THIN-FILM ELECTROLUMINESCENT DEVICES

    M KOBAYASHI, N MINO, M KONAGAI, K TAKAHASHI

    JOURNAL OF APPLIED PHYSICS   57 ( 8 ) 2905 - 2908  1985年

     概要を見る

    ZnSe:Mn dc thin-film electroluminescent (EL) devices were prepared by a molecular beam growth method on glass substrates coated with transparent conductive oxide. We found that the EL properties were affected by the grade of the oxide. The EL properties were found to depend on the range of indium diffusion from the oxide to the ZnSe:Mn host layer. The effective thickness of the host layer was varied by the In diffusion. Based upon these results, we have proposed a new type of dc thin-film EL cell, namely an Al/ZnSe:Mn/ZnSe:In/oxide structure. A ZnSe:In layer was prepared as a buffer layer that would improve the crystallinity of the ZnSe:Mn host layer.

    DOI

▼全件表示

書籍等出版物

  • 発光と受光の物理と応用

    小林洋志( 担当範囲: 38-45, 332-341)

    培風館  2008年03月

  • Blue Laser and Light Emitting Diodes,

    A. Yoshikawa, K. Kishino, M. Kobayashi, Yasuda

    オーム社  1996年

  • Widegap II-VI Compounds for Opto-electronic Applications

    M. Kobayashi, R.L. Gunshor, L.A. Kolodziejski( 担当範囲: 124-164)

    1992年

  • 半導体結晶材料総合ハンドブック

    秋田健三( 担当範囲: 45-57)

    フジ・テクノシステム  1986年06月

Misc

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  • サファイア基板上ZnTe薄膜成長における基板面方位による効果

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  • 格子不整合がZnMgTe/ZnTe光導波路の表面形状に与える影響

    風見蕗乃, SUN W, 田栗光祐, 中須大蔵, 相場貴之, 山下聡太郎, 服部翔太, 木津健, 小崎峻, 橋本勇輝, 小林正和, 朝日聡明

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  • MBE法を用いたサファイア基板上へのZnTeの横方向成長

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  • サファイアm面(10‐10)基板上ZnTe薄膜の作製と極点図による評価

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  • ZnMgTe/ZnTe導波路の結晶構造が及ぼす光学特性および結晶性の評価

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  • SrGa2S4:Eu nanoparticle phosphors prepared by a ball milling method

    M. Kobayashi, S. Hamaguchi, T. Yamamoto

    Proceedings of the World Congress on Particle Technology 6   27   137  2010年

  • X-ray Diffraction Studies of ZnMgTe/ZnTe Layered Structures and ZnTe/Si Structures

    M. Kobayashi, S. Imada, T. Baba, S. Sakurasawa

    Proceedings of 2009 II-VI Workshop     7.6  2009年

  • The Effects of Post-Annealing on the Crystallinity and the Optical Properties of SrGa2S4:Eu Nanoparticles

    S. Hamaguchi, R. Takeuchi, T. Yamamoto, M. Kobayashi

    Proceedings of the 16th International Display Workshops     PHp - 16  2009年

  • Spectroscopy of self-assembled quantum dots in ZnSe

    Hailong Zhou, A.V. Nurmikko, S. M. Kobayashi, A. Yoshikawa

    Proceedings of International Quantum Electronics Conference     15 - 16  1999年

  • MBE growth of device-quality cubic GaN on atomically flat (001)GaAs prepared by atomic-hydrogen treatment at high-temperatures

    A Yoshikawa, Z Qin, H Nagano, Y Sugure, A Jia, M Kobayashi, Y Kato, K Takahashi

    SILICON CARBIDE, III-NITRIDES AND RELATED MATERIALS, PTS 1 AND 2   264-2 ( 264-268 ) 1221 - 1224  1998年

     概要を見る

    Growth of high-quality and/or "purely cubic" GaN layers on (001) GaAs has been investigated by an rf-radical source MBE:paying particular attention to the effect of surface cleaning: and smoothing on the structural properties of the GaN epilayers. Device-quality c-GaN layers can be grown on the (001) GaAs treated by atomic hydrogen at high temperatures; the FWHM of X-ray rocking curve for the c-GaN (002) plane is as small as 80-90 arcsec and also the inclusion of the hexagonal phase GaN in the epilayer can be less than 4x10(-3).

  • MBE growth of cubic GaN and the influence of nitridation to the crystal structure

    ZX Qin, T Kurusu, AW Jia, M Kobayashi, A Yoshikawa

    BLUE LASER AND LIGHT EMITTING DIODES     546 - 548  1996年

  • Nitrogen doping of ZnSe by MOCVD using triallylamine

    Y Tanaka, S Komatsu, M Kobayashi, A Yoshikawa

    BLUE LASER AND LIGHT EMITTING DIODES     425 - 428  1996年

  • MBE growth and characterization of pseudo-ternary and quaternary alloys by superlattices consisting of (Zn,Cd)(S,Se) binary II-VI compounds

    AW Jia, C Setiagung, T Yamada, M Kobayashi, A Yoshikawa

    BLUE LASER AND LIGHT EMITTING DIODES     344 - 347  1996年

  • MBE growth of cubic and hexagonal CdS layer on (100)GaAs

    T Yamada, C Setiagung, AW Jia, M Kobayashi, A Yoshikawa

    BLUE LASER AND LIGHT EMITTING DIODES     469 - 472  1996年

  • Study of growth and doping processes of ZnSe film by in-situ optical probing

    S Komatsu, Y Tanaka, M Kobayashi, A Yoshikawa

    BLUE LASER AND LIGHT EMITTING DIODES     437 - 440  1996年

  • In-situ probing of the ZnSe MOMBE growth process by surface photo-interference method and spectroscopic surface photo-interference method

    Y Nakamura, T Yamashita, M Kobayashi, Y Kato, A Yoshikawa

    BLUE LASER AND LIGHT EMITTING DIODES     313 - 316  1996年

  • MBE Growth of ZnTe/ZnSe Heterojunction with (Ga,Se) Interfacial Layer and Reduction of Band Discontinuity

    T. Yoshida, T. Kurusu, M. Kobayashi, A. Yoshikawa

    14th Symposium Record on Alloy Semiconductor Physics and Electronics    1995年

  • A new in-situ optical probing method for the surface reaction in photo-excited heteroepitaxy of compound semiconductors

    Akihiko Yoshikawa, Msasakazu Kobayashi, S. Tokita

    Applied Surface Science   79-80 ( C ) 416 - 421  1994年05月

     概要を見る

    A new in-situ optical probing method with an atomic-scale resolution in heteroepitaxial growth is proposed. The experimental set-up of the method is very similar to another optical probing method called surface photo-absorption (SPA), but the principle is quite different. The new method is named surface photo-interference (SPI) because it is essentially concerned with photo-interference in the heteroepilayer. The principle of the SPI is as follows: the complex refractive indices of the atomic or molecular layers, which alternately appear on top of the surface during epitaxial growth of compound semiconductors, greatly affect the total phase shift of probing light during propagation in the epilayer, resulting in a change in the photo-interference signal intensity. One of the features of the SPI is that, unlike in the case of SPA, fairly low energy photons which are transparent for the epilayer can also be used as probing light. This is very preferable for studying the growth kinetics and/ or surface reaction in photo-excited epitaxial growth of widegap II-VI compounds, because the effect of photocatalytic growth-rate enhancement can be avoided when using such low energy photons as probing light. © 1994.

    DOI

  • RAMAN AND PHOTO-MODULATED REFLECTIVITY STUDIES OF ZNTE/INAS SEMICONDUCTOR HETEROSTRUCTURE UNDER HYDROSTATIC-PRESSURE

    RJ THOMAS, MS BOLEY, HR CHANDRASEKHAR, M CHANDRASEKHAR, C PARKS, AK RAMDAS, J HAN, M KOBAYASHI, RL GUNSHOR

    HIGH-PRESSURE SCIENCE AND TECHNOLOGY - 1993, PTS 1 AND 2     613 - 616  1994年

  • A New In-situ Optical Probing Method in Heteroepitaxy: Surface Photo-Interference (SPI) and Its Application to the Study of ZnSe MOMBE Growth Process

    Akihiko YOSHIKAWA, Masakazu KOBAYASHI, Sigeru TOKITA

    Proc. 3rd Japan-Korea Joint Symposium on Advanced Science and Technology for Semiconductor Materials and Devices     50 - 57  1993年

  • Design on Structures of Lattice-matched Zn(Cd)S(Se) Superlattice

    A.W. Jia, M. Kobayashi, A. Yoshikawa

    12th Symposium Record on Alloy Semiconductor Physics and Electronics     303 - 308  1993年

  • MBE Growth of p-type ZnSe Using a Mixture of N2 and He and the Application to Laser Diodes

    H. Tosaka, S. Matsumoto, T. Nagatake, T. Yoshida, M. Kobayashi, A. Yoshikawa

    12th Symposium Record on Alloy Semiconductor Physics and Electronics     319 - 320  1993年

  • Widegap II-VI Blue Laser Diodes

    R.L. Gunshor, M. Kobayashi, A.V. Nurmikko, N. Otsuka

    11th Record of Alloy Semiconductor Physics and Electronics Symposium     99 - 104  1992年

  • Blue and Green Laser Diodes and LEDs in ZnSe-Based Quantum Structures

    A.V. Nurmikko, R.L. Gunshor, M. Kobayashi

    Proc. The 1992 International Conference on Solid State Devices and Materials     342 - 344  1992年

  • HOT-EXCITON LUMINESCENCE IN ZNTE/MNTE QUANTUM-WELLS

    N PELEKANOS, J DING, Q FU, AV NURMIKKO, SM DURBIN, M KOBAYASHI, RL GUNSHOR

    PHYSICAL REVIEW B   43 ( 11 ) 9354 - 9357  1991年04月

    記事・総説・解説・論説等(学術雑誌)  

     概要を見る

    Hot-exciton luminescence phenomena are investigated in a ZnTe/MnTe single-quantum-well structure where tunneling through thin MnTe barriers suppresses the formation of thermalized luminescence. The longitudinal-optical-phonon-modulated recombination spectra are excitonic in nature and show strong resonance enhancement at energies that lie within localized states below the n = 1 exciton.

  • BLUE LUMINESCENCE FROM CDTE/MNTE SINGLE QUANTUM-WELLS

    SM DURBIN, J HAN, M KOBAYASHI, RL GUNSHOR, DR MENKE, Q FU, N PELEKANOS, AV NURMIKKO, D LI, N OTSUKA

    JOURNAL OF ELECTRONIC MATERIALS   19 ( 7 ) 27 - 27  1990年07月

    研究発表ペーパー・要旨(国際会議)  

  • FORMATION OF HETEROJUNCTION BANDOFFSETS - ISOELECTRONIC VIEWPOINT IN ZNSE-TE QUANTUM-WELLS

    Q FU, J DING, N PELEKANOS, W WALECKI, AV NURMIKKO, S DURBIN, J HAN, M KOBAYASHI, RL GUNSHOR

    20TH INTERNATIONAL CONFERENCE ON THE PHYSICS OF SEMICONDUCTORS, VOLS 1-3   20 ( 2 ) 1353 - 1356  1990年

  • STRONG ELECTRONIC CONFINEMENT IN CDTE SINGLE QUANTUM-WELLS - EXCITONIC EMISSION FROM RED TO BLUE

    J DING, N PELEKANOS, Q FU, W WALECKI, AV NURMIKKO, J HAN, S DURBIN, M KOBAYASHI, RL GUNSHOR

    20TH INTERNATIONAL CONFERENCE ON THE PHYSICS OF SEMICONDUCTORS, VOLS 1-3   20 ( 2 ) 1198 - 1201  1990年

  • HOT EXCITON LUMINESCENCE IN ZNTE-MNTE QUANTUM-WELLS

    N PELEKANOS, J DING, Q FU, AV NURMIKKO, SM DURBIN, M KOBAYASHI, RL GUNSHOR

    20TH INTERNATIONAL CONFERENCE ON THE PHYSICS OF SEMICONDUCTORS, VOLS 1-3   20 ( 3 ) 2518 - 2521  1990年

  • LOW INTERFACE STATE DENSITIES IN AS-GROWN EPITAXIAL ZNSE EPITAXIAL GAAS HETEROSTRUCTURES

    J QIU, QD QIAN, M KOBAYASHI, RL GUNSHOR, DR MENKE, D LI, N OTSUKA, LA KOLODZIEJSKI

    INSTITUTE OF PHYSICS CONFERENCE SERIES   106 ( 106 ) 201 - 206  1990年

  • LOW INTERFACE STATE DENSITY AT THE MBE GROWN, THERMALLY ANNEALED ZNSE/GAAS INTERFACE

    QD QIAN, J QIU, MR MELLOCH, JA COOPER, RL GUNSHOR, LA KOLODZIEJSKI, M KOBAYASHI

    GALLIUM ARSENIDE AND RELATED COMPOUNDS 1988   96 ( 2 ) 79 - 82  1989年

  • CdS based novel light emitting device structures grown by MBE,

    M.Kobayashi, K. Kitamura, H. Umeya, A. W. Jia, A. Yoshikawa, M. Shimotomai, Y. Kato, K. Takahashi

    Proceedings of 3rd International Symposium on Blue laser and Light Emmitting Diodes  

▼全件表示

共同研究・競争的資金等の研究課題

  • 光プローブによる結晶成長の原子・分子レベルの新しいその場観察法の研究-表面光干渉法-

    科学研究費助成事業(千葉大学)  科学研究費助成事業(一般研究(B))

  • 青色半導体レーザ作製のための複合光励起有機金属気相成長技術の開発研究

    科学研究費助成事業(千葉大学)  科学研究費助成事業(基盤研究(B))

  • ZnSe系量子箱の自然構築法開発に関する基礎研究

    科学研究費助成事業(千葉大学)  科学研究費助成事業(奨励研究(A))

  • マルチフェーズエピタキシ技術の構築によるワイドギャップ半導体の新規物性探査

    科学研究費助成事業(千葉大学)  科学研究費助成事業(基盤研究(C))

  • 環境変動による疲労損傷加速効果の実証と損傷回復処理

    科学研究費助成事業(早稲田大学)  科学研究費助成事業(基盤研究(B))

  • 輻射熱アクティブ補償エピタキシによる高品質II-VI半導体多元混晶の作製

    科学研究費助成事業(早稲田大学)  科学研究費助成事業(基盤研究(B))

  • 機械化学融合法によるコアシェル型半導体ナノ粒子の創製

    科学研究費助成事業(早稲田大学)  科学研究費助成事業(萌芽研究)

▼全件表示

講演・口頭発表等

  • Preparation of AgGaTe2 Layers on Mo with Sputtered Ag2Te Buff er Layers

    Aya Uruno, Masakazu Kobayashi

    61st Electronic Materials Conference  

    発表年月: 2019年06月

  • Orientation Shift of ZnTe Epilayers Grown on M-Plane Sapphire Substrates by Introducing Nano-Facet Structures

    KOBAYASHI, Masakazu

    2019 MRS Spring Meeting  

    発表年月: 2019年04月

  • 室温で作製したAg2Te中間層を用いた金属電極膜上AgGaTe2の作製

    宇留野彩, 小林正和

    電気学会全国大会講演論文集(CD-ROM)  

    発表年月: 2019年03月

  • スパッタ法で作製したAg2Te中間層を用いたAgGaTe2薄膜の作製

    宇留野彩, 小林正和, 小林正和

    応用物理学会春季学術講演会講演予稿集(CD-ROM)  

    発表年月: 2019年02月

  • The Growth of CuGaTe2 Thin Film by Two-step Closed Space Sublimation

    Aya Uruno, Masakazu Kobayashi

    21st International Conference on Ternary and Multinary Compounds   (Boulder Colorado USA) 

    発表年月: 2018年09月

     概要を見る

    Th-A-915

  • Pursuit of Single Domain ZnTe Layers on Sapphire Substrates

    Masakazu Kobayashi  [招待有り]

    20th International Conference on Molecular Beam Epitaxy   (Shanghai China) 

    発表年月: 2018年09月

     概要を見る

    Tu-B1-3

  • Suppression of Cu2ZnSnS4 Nanoparticle Based Film’s Decomposition during the Selenization

    K. Moriuchi, S. Taki, A, Uruno M. Kobayashi

    The 18th IEEE International Conference on Nanotechnology   (Cork Ireland) 

    発表年月: 2018年06月

     概要を見る

    T29

  • Preparation of AgGaTe2 Layers on Mo/glass Substrate by Two-step Closed Sublimation and its Application to Solar Cells

    Aya Uruno, Masakazu Kobayashi

    7th edition of the World Conference on Photovoltaic Energy Conversion   (Waikoloa Hawaii USA.) 

    発表年月: 2018年06月

     概要を見る

    285

  • The Optical Property Characterization of AgGaTe2 Prepared by the Two-Step Closed Space Sublimation

    Aya Uruno, Masakazu Kobayashi

    Compound Semiconductor Week (CSW) 2018   (Boston MA) 

    発表年月: 2018年05月

     概要を見る

    We5PP-PO9

  • Cu2Te中間層の濡れ性改善とCuGaTe2薄膜の作製

    宇留野, 彩, 桜川, 陽平, 小林 正和

    第65回応用物理学会春季学術講演会   (早稲田大学 西早稲田キャンパス)  応用物理学会  

    発表年月: 2018年03月

     概要を見る

    20a-F210-1

  • AgGaTe2太陽電池作製に向けたMo/Cr電極構造の開発

    吉野文也, 宇留野 彩, 桜川陽平, 小林正和

    平成30年電気学会全国大会   (九州大学 伊都キャンパス)  電気学会  

    発表年月: 2018年03月

     概要を見る

    2-092

  • Preparation of Cu2ZnSn(S,Se)4 Thin Films by Selenization of Cu2ZnSnS4 Layers and Suppression of By-products Formation

    Shunya Taki Kota, Moriuchi Aya Uruno, Masakazu Kobayashi

    2017 MRS FALL MEETING & EXHIBIT   (Boston MA USA) 

    発表年月: 2017年11月

     概要を見る

    ES03.05.10

  • Characterization of AgGaTe2 layer prepared by varyng Ag/Ga ratio and analysis of phase diagram

    A. Uruno, Y. Sakurakawa, M. Kobayashi

    The 27th Photovoltaic Science and Engineering Conference   (Ohtsu Shiga) 

    発表年月: 2017年11月

     概要を見る

    2ThPo.79

  • The effect of wettability on the surface structure of Te-based chalcopyrite layer grown by the closed space sublimation

    A. Uruno, Y. Sakurakawa, M. Kobayashi

    The 2017 U.S. Workshop on the Physics and Chemistry of II-VI Materials   (Chicago Illinois) 

    発表年月: 2017年10月

     概要を見る

    3.1

  • Preparation and Characterization of Cu2ZnSn(S,Se)4 Thin Films using Ball Milled Cu2ZnSnS4 Nanoparticles

    S. Taki, K. Moriuchi, A. Uruno, M. Kobayashi

    18th International Conference on II-VI Compound and Related Materials   (San Juan Puerto Rico) 

    発表年月: 2017年09月

     概要を見る

    P2-4

  • Growth of High quality ZnTe epilayers on Sapphire substrates with Multi-Buffer Layer

    T. Nakasu, M. Kobayashi, T. Asahi

    18th International Conference on II-VI Compound and Related Materials   (San Juan Puerto Rico) 

    発表年月: 2017年09月

     概要を見る

    P2-1

  • Selenazation of Cu2ZnSnS4 thin films prepared using ball milled nanoparticles

    S. Taki, K. Moriuchi, A. Uruno, M. Kobayashi

    The European Materials Research Society   (Warsaw Poland) 

    発表年月: 2017年09月

     概要を見る

    S.P1.8

  • 近接昇華法によるTe系カルコパイライトの作製と濡れ性の影響

    宇留野彩, 桜川陽平小林正和

    第78回応用物理学会秋季学術講演会   (福岡国際会議場、福岡)  応用物理学会  

    発表年月: 2017年09月

     概要を見る

    5p-A411-13

  • Cu2Te層を利用した2段階近接昇華法によるCuGaTe2薄膜の作製

    桜川陽平, 宇留野彩, 小林正和

    第78回応用物理学会秋季学術講演会   (福岡国際会議場、福岡)  応用物理学会  

    発表年月: 2017年09月

     概要を見る

    5p-A411-12

  • Cu2ZnSnS4ナノ粒子塗布膜のSe化アニールとSn蒸気の添加効果

    森内洸太, 瀧駿也, 宇留野彩, 小林正和

    第78回応用物理学会秋季学術講演会   (福岡国際会議場、福岡)  応用物理学会  

    発表年月: 2017年09月

     概要を見る

    5p-A411-11

  • サファイア基板上ZnTe薄膜のエピタキシーメカニズムの解析

    中須大蔵, 小林正和, 朝日聡明  [招待有り]

    第78回応用物理学会秋季学術講演会   (福岡国際会議場、福岡)  応用物理学会  

    発表年月: 2017年09月

     概要を見る

    5p-A411-1

  • Crystal Growth Mechanism of ZnTe epilayers on Sapphire Substrate

    T. Nakasu, M, Kobayashi, T. Asahi

    59th Annual Electronic Materials Conference   (South Bend Indiana USA) 

    発表年月: 2017年06月

     概要を見る

    G4

  • サファイア基板上ZnTe薄膜成長における基板面方位による効果

    中須大蔵, 小高圭佑, 小林正和, 朝日聡明

    第64回応用物理学会春季学術講演会   (パシフィコ横浜)  応用物理学会  

    発表年月: 2017年03月

     概要を見る

    17a-513-11

  • AgGaTe2膜内のAg/Ga比が膜質に与える影響と状態図による解析

    宇留野彩, 鬼界伸一郎, 末次由里, 桜川陽平, 小林正和

    第64回応用物理学会春季学術講演会   (パシフィコ横浜)  応用物理学会  

    発表年月: 2017年03月

     概要を見る

    17a-513-6

  • AgGaTe2薄膜内における副生成物が光学的特性に与える影響

    鬼界伸一郎, 宇留野彩, 笹原宏希, 小林正和

    平成29年電気学会全国大会   (富山大学)  電気学会  

    発表年月: 2017年03月

     概要を見る

    2-083

  • Cu2ZnSnS4ナノ粒子塗布膜のSe化アニールとアニール条件の改善

    瀧 駿也, 森内, 洸太, 宇留野, 彩, 張, 険峰, 小林 正和

    平成29年電気学会全国大会   (富山大学)  電気学会  

    発表年月: 2017年03月

     概要を見る

    2-082

  • Nucleation of Cu2Te layer by a closed space sublimation method toward the growth of Te based Chalcopyrite

    Y. Sakurakawa, A. Uruno, M. Kobayashi

    44th Conference on the Physics and Chemistry of Surfaces and Interfaces   (Santa Fe New Mexico) 

    発表年月: 2017年01月

     概要を見る

    WeA44

  • Defect Density Reduction in Core layer of ZnTe Electro-Optical Waveguide by Low Lattice Mismatched Interfaces

    W. Sun, T, Nakasu K, Odaka M, Kobayashi T. Asahi

    44th Conference on the Physics and Chemistry of Surfaces and Interfaces   (Santa Fe New Mexico) 

    発表年月: 2017年01月

     概要を見る

    WeM39

  • サファイア基板上ZnTe薄膜の分子線エピタキシー成長

    中須大蔵, 小林正和, 朝日聡明

    第5回結晶工学未来塾研究ポスター発表会   (東京農業工業大学 小金井) 

    発表年月: 2016年11月

     概要を見る

    40

  • High quality AgGaTe2 layers formed from Ga2Te3/Ag2Te two layer structures

    A. Uruno, Y. Sakurakawa, M. Kobayashi

    The 2016 U.S. Workshop on the Physics and Chemistry of II-VI Materials   (Baltimore MD) 

    発表年月: 2016年10月

     概要を見る

    4_3

  • Influence of nano-facet structures on the orientation of the ZnTe film on sapphire substrate

    T. Nakasu, W. Sun, M. Kobayashi, T. Asahi

    32nd North American Molecular Beam Epitaxy Conference   (Saratoga Springs New York) 

    発表年月: 2016年09月

     概要を見る

    MoP26

  • Influence of the sapphire substrate surface treatment on the domain structure of the ZnTe epilayer

    T. Nakasu, W. Sun, M. Kobayashi, T. Asahi

    19th International Conference on Molecular Beam Epitaxy   (Montpellier France) 

    発表年月: 2016年09月

  • Cu2ZnSnS4ナノ粒子塗布膜の Se 化アニールと副生成物の抑制

    瀧 駿也, 宇留野, 彩, 張険峰, 小林 正和

    第77回応用物理学会秋季学術講演会   (朱鷺メッセ 新潟)  応用物理学会  

    発表年月: 2016年09月

     概要を見る

    15a-A34-1

  • 近接昇華法によるGa2Te3/Ag2Te積層構造からのAgGaTe2薄膜作製

    宇留野彩, 桜川陽平, 小林正和

    第77回応用物理学会秋季学術講演会   (朱鷺メッセ 新潟)  応用物理学会  

    発表年月: 2016年09月

     概要を見る

    13p-D61-8

  • サファイア基板表面のナノファセット構造によるZnTe薄膜の配向制御

    中須大蔵, 孫惟哲, 小林正和, 朝日聡明

    第77回応用物理学会秋季学術講演会   (朱鷺メッセ 新潟)  応用物理学会  

    発表年月: 2016年09月

     概要を見る

    13p-D61-4

  • Cu2ZnSn(S,Se)4 thin films prepared using Cu2ZnSnS4 nanoparticles

    S. Taki, Y. Umejima A, Uruno, X. Zhang M. Kobayashi

    16th International Conference on Nanotechnology (IEEE NANO 2016)   (Sendai Japan) 

    発表年月: 2016年08月

     概要を見る

    WePM11.5

  • Growth and characterization of ZnTe layers on severely lattice mismatched sapphire substrates by MBE

    T. Nakasu, W. Sun, M. Kobayashi, T. Asahi

    18th International Conference on Crystal Growth and Epitaxy   (Nagoya Japan) 

    発表年月: 2016年08月

     概要を見る

    Fr1-T04-7

  • The growth of AgGaTe2 layer on Si substrate by two-step closed space sublimation and its application to solar cell fabrications

    A. Uruno, M. Kobayashi

    The 43rd IEEE Photovoltaic Specialists Conference (PVSC43)   (Portland OR) 

    発表年月: 2016年06月

     概要を見る

    143

  • Growth and Crystal Orientation of ZnTe on m-Plane Sapphire with Nano-faceted Structure

    T. Nakasu, S. Hattori, Y. Hashimoto, W. Sun J, Wang, M. Kobayashi, T. Asahi

    58th Electronic Materials Conference   (Newark Delaware USA) 

    発表年月: 2016年06月

     概要を見る

    Z8

  • Growth and solar cell applications of AgGaTe2 layers by closed space sublimation using the mixed source of Ag2Te and Ga2Te3

    A. Uruno, S. Kikai, Y. Suetsugu, M. Kobayashi

    43rd International Symposium on Compound Semiconductors   (Toyama Japan) 

    発表年月: 2016年06月

     概要を見る

    MoP-ISCS-014

  • The growth process analysis of the ZnTe layer on the m-plane sapphire substrate with nano-facet structures

    T. Nakasu, T. Kizu, W. Sun, F. Kazami, M. Kobayashi, T. Asahi

    43rd International Symposium on Compound Semiconductors   (Toyama Japan) 

    発表年月: 2016年06月

     概要を見る

    MoP-ISCS-012

  • Ag2Te中間層を導入したSi基板上のAgGaTe2作製と太陽電池応用

    宇留野彩, 小林正和

    第63回応用物理学会春季学術講演会   (東京工業大学)  応用物理学会  

    発表年月: 2016年03月

     概要を見る

    22p-H116-6

  • Se蒸気圧制御アニールによるCu2ZnSn(S,Se)4の作製と太陽電池応用

    梅嶋悠人, 瀧駿也, 上村一生, 宇留野彩, 張険峰, 小林正和

    第63回応用物理学会春季学術講演会   (東京工業大学)  応用物理学会  

    発表年月: 2016年03月

     概要を見る

    22p-H116-5

  • フッ酸系エッチャントによるZnTeのメサエッチングとZnMgTe/ZnTe光導波路のリッジ化

    風見蕗乃, 孫惟哲, 王兢, 中須大蔵, 服部翔太, 木津健, 橋本勇輝, 玉川陽菜, 小高圭佑, 山本洋輔, 小林正和, 朝日聡明

    第63回応用物理学会春季学術講演会   (東京工業大学)  応用物理学会  

    発表年月: 2016年03月

     概要を見る

    22a-H116-3

  • ナノファセットを持つサファイアm面基板上ZnTe薄膜の成長過程解析

    中須大蔵, 服部翔太, 木津健, 橋本勇輝, 孫惟哲, 風見蕗乃, 王兢, 山本洋輔, 玉川陽菜, 小高圭佑, 小林正和, 朝日聡明

    第63回応用物理学会春季学術講演会   (東京工業大学)  応用物理学会  

    発表年月: 2016年03月

     概要を見る

    22a-H116-2

  • サファイア基板の化学処理がZnTe薄膜のドメイン構造形成に与える効果

    中須大蔵, 木津健, 服部翔太, 橋本勇輝, 孫惟哲, 風見蕗乃, 王兢, 小高圭佑, 玉川陽菜, 山本洋輔, 小林正和, 朝日聡明

    第63回応用物理学会春季学術講演会   (東京工業大学)  応用物理学会  

    発表年月: 2016年03月

     概要を見る

    22a-H116-1

  • 低温フォトルミネッセンス法によるAgGaTe2薄膜の光学的特性評価

    鬼界伸一郎, 宇留野彩, 末次由里

    平成28年電気学会全国大会   (東北大学)  電気学会  

    発表年月: 2016年03月

     概要を見る

    NO.2-090

  • フッ酸系エッチャントを用いたZnMgTe/ZnTe光導波路のリッジ加工

    風見蕗乃, 孫惟哲, 王兢, 中須大蔵, 服部翔太, 木津健, 橋本勇輝, 小林正和, 朝日聡明

    平成28年電気学会全国大会   (東北大学)  電気学会  

    発表年月: 2016年03月

     概要を見る

    NO.2-092

  • MBE法により作製されたサファイア基板上ZnTe薄膜の結晶性評価

    玉川陽菜, 中須大蔵, 服部翔太, 木津健, 橋本勇輝, 小高圭佑, 山本洋輔, 孫惟哲, 風見蕗乃, 王兢, 小林正和, 朝日聡明

    平成28年電気学会全国大会   (東北大学)  電気学会  

    発表年月: 2016年03月

     概要を見る

    No2-091

  • Epitaxial lateral overgrowth Epitaxial of ZnTe on sapphire substrates using SiO2 mask

    S. Hattori T, Nakasu T. Kizu, Y, Hashimoto W. Sun, F. Kazami, M. Kobayashi, T. Asahi

    The 43rd Conference on the Physics and Chemistry of Surfaces and Interfaces   (Palm Springs California USA) 

    発表年月: 2016年01月

     概要を見る

    We1445

  • Two-step-index ZnMgTe/ZnTe Waveguide Structures with Improved Crystal Quality

    W. Sun, F, Kazami J, Wang T, Nakasu S. Hattori, T. Kizu, Y. Hashimoto, M. Kobayashi T. Asahi

    2015 MRS Fall Meeting   (Boston Massachusetts USA) 

    発表年月: 2015年11月

     概要を見る

    GG10.04

  • High quality AgGaTe2 layers on Si substrates with Ag2Te buffer layers

    Aya Uruno, Masakazu kobayashi

    THE U.S. WORKSHOP on the physics and chemistry of II-VI materials   (Chicago IL) 

    発表年月: 2015年10月

     概要を見る

    6.5.

  • Electro-Optic Characteristics Improvement of ZnMgTe/ZnTe Waveguide Devices

    W.C. Sun, F, Kazami J, Wang T, Nakasu S. Hattori, T. Kizu, Y. Hashimoto, M. Kobayashi, T. Asahi  [招待有り]

    The 2015 International Conference on Solid State Devices and Materials   (Sapporo Japan) 

    発表年月: 2015年09月

     概要を見る

    PS-7-22

  • Crystallographic and Optical Characterizations of Ag(Ga,Al)Te2 Layers Grown on c-plane Sapphire Substrates by Closed Space Sublimation

    Aya Uruno Yuji Takeda Tomohiro Inoue, Masakazu Kobayashi

    The 17th International Conference on II-VI Compounds   (Paris) 

    発表年月: 2015年09月

     概要を見る

    TuC-3

  • ZnTe Layers on R- and S-plane Sapphire Substrates

    T. Nakasu, S.Yamashita, T. Aiba, S. Hattori, T. Kizu, W. Sun, K. Taguri, F. Kazami, Y. Hashimoto, S. Ozaki, M. Kobayashi, T. Asahi

    The 17th International Conference on II-VI Compounds   (Paris) 

    発表年月: 2015年09月

     概要を見る

    MoA-2

  • サファイアm 面基板の熱処理とZnTe 薄膜の結晶性改善

    橋本 勇輝, 中須, 大蔵, 木津, 健, 服部, 翔太, 孫, 惟哲, 風見, 蕗乃, 小林, 正和, 朝日 聡明

    第76回応用物理学会秋季学術講演会   (名古屋国際会議場)  応用物理学会  

    発表年月: 2015年09月

     概要を見る

    13p-PB1-1

  • SiO2 マスクを用いたサファイア基板上ZnTeの選択成長

    服部 翔太, 中須, 大蔵, 橋本, 勇輝, 木津, 健 孫, 惟哲, 風見, 蕗乃, 小林, 正和, 朝日 聡明

    第76回応用物理学会秋季学術講演会   (名古屋国際会議場)  応用物理学会  

    発表年月: 2015年09月

     概要を見る

    13a-1A-1

  • ZnMgTe/ZnTe waveguide with two-step-index cladding layers structure

    WeiChe Sun Fukino, Kazami Jing, Wang Taizo, Nakasu Shota Hattori, Takeru Kizu, Yuki Hashimoto, Masakazu Kobayashi, Toshiaki Asahi

    第76回応用物理学会秋季学術講演会   応用物理学会  

    発表年月: 2015年09月

     概要を見る

    E 13a-1A-2

  • Influence of the Lattice Mismatch Strain on the Surface Morphology of ZnMgTe/ZnTe Electro-Optical Waveguide Structure

    Fukino Kazami, Wei-che Sun, Kosuke Taguri Taizo, Nakasu Takayuki Aiba Sotaro, Yamashita Shota Hattori, Takeru Kizu, Masakazu Kobayashi, Toshiaki Asahi

    42nd International Symposium on Compound Semiconductors   (University of California Santa Barbara CA USA) 

    発表年月: 2015年06月

     概要を見る

    Mo4PP-O.6

  • Surface texture and crystallinity variation of ZnTe epilayers grown on the step-terrace structure of the sapphire substrate

    57th Electronic Materials Conference   (The Ohio State University in Columbus Ohio) 

    発表年月: 2015年06月

     概要を見る

    PS-3

  • Epitaxial Relationship Analysis between ZnTe Epilayers and Sapphire Substrates

    57th Electronic Materials Conference   (The Ohio State University in Columbus Ohio) 

    発表年月: 2015年06月

     概要を見る

    PS-2

  • Ba2ZnS3:Mn赤色蛍光体ナノ粒子多層膜構造の作製

    古井三誉子, 宇留野彩, 小林正和

    平成27年電気学会全国大会   (東京都市大学世田谷キャンパス)  電気学会  

    発表年月: 2015年03月

     概要を見る

    2-080

  • MBE法によるZnTeのELO

    橋本勇輝, 中須大蔵, 服部翔太, 山下聡太郎, 相場貴之, 木津健孫惟哲, 田栗光祐, 風見蕗乃, 小林正和, 朝日聡明

    平成27年電気学会全国大会   (東京都市大学世田谷キャンパス)  電気学会  

    発表年月: 2015年03月

     概要を見る

    2-103

  • 近接昇華法によるAg(Ga,Al)Te2混晶の作製とバンドギャップの評価

    薄井綾香, 宇留野彩, 井上朋大, 竹田裕二, 小林正和

    平成27年電気学会全国大会   (東京都市大学世田谷キャンパス)  電気学会  

    発表年月: 2015年03月

     概要を見る

    2-101

  • ナノ粒子Cu2ZnSnS4薄膜のSe化とX線回折によるアニール条件の検討

    井狩華奈美, 梅嶋悠人, 上村一生, 張 険峰, 小林正和

    平成27年電気学会全国大会   (東京都市大学世田谷キャンパス)  電気学会  

    発表年月: 2015年03月

     概要を見る

    2-100

  • The electro-optic signal improvement by ZnMgTe/ZnTe waveguide structures

    WeiChe Sun Kosuke, Taguri, Fukino Kazami

    第62回応用物理学会春季学術講演会   (東海大学湘南キャンパス [)  応用物理学会  

    発表年月: 2015年03月

     概要を見る

    13p-A17-6

  • 格子不整合がZnMgTe/ZnTe光導波路の表面形状に与える影響

    風見蕗乃, 孫惟哲, 田栗光祐, 中須大蔵, 相場貴之, 山下聡太朗, 服部翔太, 木津健, 小?俊, 橋本勇輝, 小林正和, 朝日聡明

    第62回応用物理学会春季学術講演会   (東海大学湘南キャンパス [)  応用物理学会  

    発表年月: 2015年03月

     概要を見る

    13p-A17-5

  • S面サファイア基板上ZnTe薄膜の作製と成長方位関係の解析

    中須 大蔵, 山下, 聡太郎, 相場, 貴之, 木津, 健, 服部, 翔太, 孫, 惟哲, 田栗, 光祐, 風見, 蕗乃, 小, 峻 橋本, 勇輝, 小林, 正和, 朝日 聡明

    第62回応用物理学会春季学術講演会   (東海大学湘南キャンパス [)  応用物理学会  

    発表年月: 2015年03月

     概要を見る

    13p-A17-4

  • オフ角を持つサファイア a面基板のステップ構造によるZnTeドメイン構造の改善

    山下 聡太郎, 中須, 大蔵, 木津, 健, 相場, 貴之, 服部, 翔太, 孫, 惟哲, 田栗, 光祐, 風見, 蕗乃, 橋本, 勇輝, 小, 峻, 小林, 正和, 朝日 聡明

    第62回応用物理学会春季学術講演会   (東海大学湘南キャンパス [)  応用物理学会  

    発表年月: 2015年03月

     概要を見る

    13p-A17-3

  • サファイア基板表面のステップ構造がZnTe薄膜成長にもたらす効果

    木津 健, 中須, 大蔵, 山下, 聡太郎, 相場, 貴之, 服部, 翔太, 孫, 惟哲, 田栗, 光祐, 風見, 蕗乃, 小, 峻 橋本, 勇輝, 小林, 正和, 朝日 聡明

    第62回応用物理学会春季学術講演会   (東海大学湘南キャンパス [)  応用物理学会  

    発表年月: 2015年03月

     概要を見る

    13p-A17-2

  • 高温ZnTeバッファ層導入によるZnTe薄膜のドメイン構造の改善

    相場 貴之, 中須, 大蔵, 山下, 聡太郎, 服部, 翔太, 木津, 健 孫, 惟哲, 田栗, 光祐, 風見, 蕗乃, 橋本, 勇輝, 小, 峻, 小林, 正和, 朝日 聡明

    第62回応用物理学会春季学術講演会   (東海大学湘南キャンパス [)  応用物理学会  

    発表年月: 2015年03月

     概要を見る

    13p-A17-1

  • 近接昇華法を用いたサファイア基板上のAg(Ga,Al)Te2混晶作製

    宇留野彩, 薄井綾香, 竹田裕二, 井上朋大, 小林正和

    第62回応用物理学会春季学術講演会   (東海大学湘南キャンパス [)  応用物理学会  

    発表年月: 2015年03月

     概要を見る

    13a-A17-1

  • Se蒸気圧制御によるCZTSナノ粒子薄膜のSe化

    梅嶋 悠人, 井狩, 華奈美, 上村, 一生, 張険峰, 小林 正和

    第62回応用物理学会春季学術講演会   (東海大学湘南キャンパス [)  応用物理学会  

    発表年月: 2015年03月

     概要を見る

    12p-A26-5

  • 近接昇華法を用いたAgGaTe2とAgAlTe2の結晶性の評価と混晶作製

    宇留野彩, 薄井綾香, 井上朋大, 竹田裕二, 小林正和

    第6回 半導体材料・デバイスフォーラム   (都城 宮崎) 

    発表年月: 2014年12月

  • ワイドギャップII-VI族化合物半導体の現状

    小林 正和  [招待有り]

    第6回 半導体材料・デバイスフォーラム   (都城 宮崎) 

    発表年月: 2014年12月

  • The crystallographic characterization of AgGaTe2 and AgAlTe2 grown by closed space sublimation

    Aya Uruno Ayaka Usui, Masakazu Kobayashi

    The 2014 II-VI Workshop   (Balltimore MD USA) 

    発表年月: 2014年10月

     概要を見る

    [4-2]

  • The Growth of AgGaTe2 layers onglass substrates with Ag2Te buffer layer by closed space sublimation method

    A. Uruno, A. Usui, M. Kobayashi

    19th International Conference on Ternary and Multinary Compounds   (Niigata) 

    発表年月: 2014年09月

     概要を見る

    Tue-O-10B

  • Control of Domain Orientation during the MBE Growth of ZnTe on a-Plane Sapphire

    T. Nakasu, T. Aiba, S. Yamashita, S. Hattori, W-C. Sun, K. Taguri, F. Kazami, M. Kobayashi, T. Asahi

    18th International Conference on Molecular Beam Epitaxy   (Flagstaff Arizona) 

    発表年月: 2014年09月

     概要を見る

    TuC3-5

  • 近接昇華法で作製したAgGaTe2の仕込み原料による影響

    宇留野彩, 薄井綾香, 竹田裕二, 井上朋大, 小林正和

    第75回応用物理学会秋季学術講演会   (北海道大学札幌キャンパス)  応用物理学会  

    発表年月: 2014年09月

     概要を見る

    17p-A12- 13

  • MBE 法を用いたサファイア基板上へのZnTe の横方向成長

    服部翔太, 中須大蔵, 山下聡太郎, 相場貴之, 孫惟哲, 田栗光祐, 風見蕗乃, 木津 健, 小林正和, 朝日聡明, 武井勇樹, 宇高勝之

    第75回応用物理学会秋季学術講演会   (北海道大学札幌キャンパス)  応用物理学会  

    発表年月: 2014年09月

     概要を見る

    17p-A12- 5

  • サファイアa 面基板のオフ角がZnTe ドメイン構造へ与える影響の評価

    山下聡太郎, 中須大蔵, 相場貴之, 服部翔太, 孫 惟哲, 田栗光祐, 風見蕗乃, 木津 健, 小林正和, 朝日聡明

    第75回応用物理学会秋季学術講演会   (北海道大学札幌キャンパス)  応用物理学会  

    発表年月: 2014年09月

     概要を見る

    17p-A12- 4

  • c,r,m 面サファイア基板/ZnTe 薄膜の成長方位関係の解析

    中須大蔵, 山下聡太郎, 相場貴之, 服部翔太, 孫 惟哲, 田栗光祐, 風見蕗乃, 木津 健, 小林正和, 朝日聡明

    第75回応用物理学会秋季学術講演会   (北海道大学札幌キャンパス)  応用物理学会  

    発表年月: 2014年09月

     概要を見る

    17p-A12- 3

  • Fluorescence Intensity Cure of Ba2ZnS3:Mn Red Phosphor Nanoparticles toward the Silicon Solar Cell Application

    MIYOKO FURUI Y, UMEJIMA M, KOBAYASHI

    The 2014 International Conference on Nanoscience + Technology   (Vail Colorado) 

    発表年月: 2014年07月

     概要を見る

    NO-WeM8

  • Effect of (0001) Surface on the Orientation of ZnTe Epilayer/Sapphire Substrate

    Taizo Nakasu, Takayuki Aiba Sotaro, Yamashita Shota, Hattori Wei-Che Sun, Kosuke Taguri, Fukino Kazami, Masakazu Kobayashi, Toshiaki Asahi

    56th Electronic Materials Conference   (University of California Santa Barbara) 

    発表年月: 2014年06月

     概要を見る

    PS9

  • The growth of AgGaTe2 layer on Mo and effect of the Ag2Te buffer layer on the film quality

    Uruno Aya Usui Aya, Takeda Yuji, Inoue Tomohiro, Kobayashi Masakazu

    41st International Symposium on Compound Semiconductors   (Le Corum Montpellier France) 

    発表年月: 2014年05月

     概要を見る

    P42

  • AgAlTe2の近接昇華法による成長と極点図法による配向性の評価

    宇留野彩, 薄井綾香, 井上朋大, 竹田裕二, 小林正和

    第61回応用物理学会春季学術講演会   (青山学院大学淵野辺キャンパス)  応用物理学会  

    発表年月: 2014年03月

     概要を見る

    18a-D2 - 9

  • Mo膜上のAgGaTe2の成長とAg2Teバッファ層による影響

    宇留野彩, 薄井綾香, 竹田裕二, 井上朋大, 小林正和

    第61回応用物理学会春季学術講演会   (青山学院大学淵野辺キャンパス)  応用物理学会  

    発表年月: 2014年03月

     概要を見る

    18a-D2 - 8

  • サファイアn面基板上ZnTe薄膜成長とドメイン構造の解析

    中須大蔵, 山下聡太郎, 相場貴之, 孫 惟哲, 田栗光祐, 服部翔太, 風見蕗乃, 小林正和, 都甲浩芳, 朝日聡明

    第61回応用物理学会春季学術講演会   (青山学院大学淵野辺キャンパス)  応用物理学会  

    発表年月: 2014年03月

     概要を見る

    18a-D2 - 3

  • 広域逆格子マップ測定によるc面サファイア基板上ZnTe薄膜の評価

    相場貴之, 中須大蔵, 山下聡太郎, 孫 惟哲, 田栗光祐, 服部翔太, 風見蕗乃, 小林正和, 都甲浩芳, 朝日聡明

    第61回応用物理学会春季学術講演会   (青山学院大学淵野辺キャンパス)  応用物理学会  

    発表年月: 2014年03月

     概要を見る

    18a-D2 - 2

  • サファイアa面基板上に作製したZnTe薄膜のドメイン構造の解析

    山下聡太郎, 中須大蔵, 相場貴之, 孫 惟哲, 田栗光祐, 服部翔太, 風見蕗乃, 小林正和, 朝日聡明, 都甲浩芳

    第61回応用物理学会春季学術講演会   (青山学院大学淵野辺キャンパス)  応用物理学会  

    発表年月: 2014年03月

     概要を見る

    18a-D2 - 1

  • 赤色蛍光ナノ粒子Ba2ZnS3:Mnの蛍光強度回復とSi太陽電池への応用

    梅嶋悠人, 古井三誉子, 小林正和

    平成26年電気学会全国大会   (愛媛大学 城北キャンパス)  応用物理学会  

    発表年月: 2014年03月

     概要を見る

    12-B2-2-101

  • 近接昇華法によりサファイアa面上へ作製したAgAlTe2およびAgGaTe2の配向性評価

    薄井綾香, 宇留野 彩, 井上朋大, 竹田裕二, 小林正和

    平成26年電気学会全国大会   (愛媛大学 城北キャンパス)  応用物理学会  

    発表年月: 2014年03月

     概要を見る

    12-B2-2-100

  • 異なるMo膜上への近接昇華法によるAgAlTe2の作製

    竹田裕二, 宇留野 彩, 薄井綾香, 井上朋大, 小林正和

    平成26年電気学会全国大会   (愛媛大学 城北キャンパス)  応用物理学会  

    発表年月: 2014年03月

     概要を見る

    12-B2-2-099

  • Different Orientation of AgGaTe2 and AgAlTe2 Layers Grown on a-plane Sapphire Substrates by a Closed Space Sublimation Method

    A. Usui A, Uruno, M. Kobayashi

    41st Conference on the Physics and Chemistry of Surfaces and Interfaces   (Santa Fe New Mexico) 

    発表年月: 2014年01月

     概要を見る

    Mo0930

  • Molecular Beam Epitaxy Growth of ZnTe/ZnMgTe Waveguide Structures and Propagation Light Intensity Change by the Applied Field

    W. Sun, T, Nakasu, K. Taguri, T. Aiba, S. Yamashita, M. Kobayashi, H. Togo, S. Asahi

    The 30th North American Conference on Molecular Beam Epitaxy   (Banff Canada) 

    発表年月: 2013年10月

     概要を見る

    P20

  • Growth of AgGaTe2 Layers for a Novel Photovoltaic Material

    Aya Uruno Ayaka Usui, Masakazu Kobayashi

    2013 II-VI Workshop   (Chicago IL) 

    発表年月: 2013年10月

     概要を見る

    8.6

  • Growth and Electro-Optical Characteri-zation of ZnMgTe/ZnTe Waveguide by Molecular Beam Epitaxy

    Wei-Che Sun Taizo, Nakasu Kousuke, Taguri Takayuki Aiba, Sotaro Yamashita, Masakazu Kobayashi Hiroyoshi Togo, Toshiaki Asahi

    The 16th International Conference on II-VI Compounds and Related Materials   (Nagahama) 

    発表年月: 2013年09月

     概要を見る

    Th-A3

  • Preparation of High Transmittance Ba2ZnS3:Mn Red Phosphor Nanoparticle Layers for Si Solar Cells

    Miyoko Furui, Masakazu Kobayashi

    The 16th International Conference on II-VI Compounds and Related Materials   (Nagahama) 

    発表年月: 2013年09月

     概要を見る

    We-P16

  • Growth of CuGaTe2 Based Compounds by a Closed Space Sublimation Method

    Ayaka Usui Aya, Uruno, Masakazu Kobayashi

    The 16th International Conference on II-VI Compounds and Related Materials   (Nagahama) 

    発表年月: 2013年09月

     概要を見る

    We-P12

  • MBE Growth and Characterization of ZnTe Epilayers on m-Plane Sapphire Substrates

    T. Nakasu, W. Sun, S. Yamashita, T. Aiba, K. Taguri, M. Kobayashi T. Asahi, H. Togo

    The 16th International Conference on II-VI Compounds and Related Materials   (Nagahama) 

    発表年月: 2013年09月

     概要を見る

    We-B2

  • Growth of AgGaTe2 Layers on a- and c-Plane Sapphire Substrates by a Closed Space Sublimation Method

    Aya Uruno Ayaka Usui, Masakazu Kobayashi

    The 16th International Conference on II-VI Compounds and Related Materials   (Nagahama) 

    発表年月: 2013年09月

     概要を見る

    Mo-B2

  • ZnTe/ZnMgTe導波路への電圧印加と透過光強度変化の検討

    田栗光祐, 孫惟哲, 中須大蔵, 相場貴之, 山下聡太郎, 小林正和, 朝日聡明, 都甲浩芳

    第74回応用物理学会秋季学術講演会   (京田辺 同志社大学)  応用物理学会  

    発表年月: 2013年09月

     概要を見る

    16a-B4-4

  • 各種面方位のサファイア基板上ZnTe薄膜の成長と配向方位制御

    中須大蔵, 孫惟哲, 山下聡太郎, 相場貴之, 田栗光祐, 小林正和, 都甲浩芳, 朝日聡明

    第74回応用物理学会秋季学術講演会   (京田辺 同志社大学)  応用物理学会  

    発表年月: 2013年09月

     概要を見る

    16a-B4-3

  • 近接昇華法により成長したAgGaTe2の極点図法による配向性の解析

    宇留野彩, 薄井綾香, 小林正和

    第74回応用物理学会秋季学術講演会   (京田辺 同志社大学)  応用物理学会  

    発表年月: 2013年09月

     概要を見る

    16a-B4-2

  • (211) oriented domain formation during the growth of ZnTe on m-plane sapphire by MBE

    Taizo Nakasu, Masakazu Kobayashi Hiroyoshi Togo, Toshiaki Asahi

    The 55th Annual Electronic Materials Conference   (South Bend IN) 

    発表年月: 2013年06月

     概要を見る

    X5

  • (211) oriented ZnTe growth on m-plane sapphire by MBE

    T. Nakasu, M. Kobayashi, H. Togo, T. Asahi

    The 40th International Symposium on Compound Semiconductors   (Kobe) 

    発表年月: 2013年05月

     概要を見る

    MoPC-01-10

  • Deposition of AgGaTe2 on Sapphire Substrates by Closed Space Sublimation

    A. Uruno, A. Usui, M. Kobayashi

    The 40th International Symposium on Compound Semiconductors   (Kobe) 

    発表年月: 2013年05月

     概要を見る

    MoPC-01-17

  • 近接昇華法による各種面方位サファイア基板上のAgGaTe2作製

    宇留野彩, 小林正和

    第60回応用物理学会春季学術講演会   (神奈川工科大学)  応用物理学会  

    発表年月: 2013年03月

     概要を見る

    27p-G19-6

  • サファイアm面基板上ZnTe薄膜の成長とバッファ層による影響の評価

    中須大蔵, 小林正和, 都甲浩芳, 朝日聡明

    第60回応用物理学会春季学術講演会   (神奈川工科大学)  応用物理学会  

    発表年月: 2013年03月

     概要を見る

    27p-G19-5

  • 近接昇華法によるCuGaTe2の成長

    薄井綾香, 宇留野彩, 中田和輝, 小林正和

    平成25年電気学会全国大会   (名古屋大学)  電気学会  

    発表年月: 2013年03月

     概要を見る

    2-079

  • 近接昇華法によるサファイア基板上のAgGaTe2の成長

    宇留野 彩, 薄井綾香, 中田和輝, 小林正和

    平成25年電気学会全国大会   (名古屋大学)  電気学会  

    発表年月: 2013年03月

     概要を見る

    2-078

  • 赤色蛍光体ナノ粒子透明薄膜の作製と透過率の改良

    古井三誉子, 小林正和

    平成25年電気学会全国大会   (名古屋大学)  電気学会  

    発表年月: 2013年03月

     概要を見る

    2-093

  • MBE growth and pole figure analysis of ZnTe epilayers on sapphire substrates

    Taizo Nakasu, Masakazu Kobayashi

    The 17th European Molecular Beam Epitaxy Workshop   (Levi Finland) 

    発表年月: 2013年03月

     概要を見る

    TuP.39

  • MBE Growth of ZnTe epilayers on m-plane (10-10) sapphire substrates

    Taizo Nakasu, Yuki, Kumagai Kimihiro Nishimura, Masakazu Kobayashi

    The 17th International Conference on Molecular Beam Epitaxy   (Nara) 

    発表年月: 2012年09月

     概要を見る

    ThB-3-2

  • 近接昇華法による透明基板上へのAgGaTe2の作製

    宇留野彩, 小林正和

    第73回応用物理学会学術講演会   (愛媛大学)  応用物理学会  

    発表年月: 2012年09月

     概要を見る

    14p-H8-6

  • サファイアm 面(10-10)基板上ZnTe 薄膜の作製と極点図による評価

    中須大蔵, 小林正和, 朝日聡明

    第73回応用物理学会学術講演会   (愛媛大学)  応用物理学会  

    発表年月: 2012年09月

     概要を見る

    14p-H8-2

  • Preparation of nanoparticle phosphor films and its application to solar cells

    Masakazu Kobayashi AyakaYagi, Sayako Hamaguchi

    IEEE 12th International Conference on Nanotechnology   (International Convention Centre (ICC) Birmingham UK) 

    発表年月: 2012年08月

  • Fabrication of nanoparticle phosphors and application to the transparent ink

    Masakazu Kobayashi, Ayaka Yagi

    International Conference on Nanoscience + Technology   (University of Paris Sorbonne Paris France) 

    発表年月: 2012年07月

     概要を見る

    SO9-3

  • Growth of AgGaTe2 Layers by a Closed Space Sublimation Method

    Aya Uruno Taizo Nakasu, Masakazu Kobayashi

    The Electronic Materials Conference   (Pennsylvania State University) 

    発表年月: 2012年06月

     概要を見る

    L9

  • Growth of ZnTe Epilayers on Severely Lattice Mismatched c-plane Sapphire by MBE

    Taizo Nakasu, Yuki, Kumagai Kimihiro Nishimura Aya Uruno, Masakazu Kobayashi

    The Electronic Materials Conference   (Pennsylvania State University) 

    発表年月: 2012年06月

     概要を見る

    L4

  • Fabrication of ZnMgTe/ZnTe/ZnMgTe Waveguide Structures

    Yuki Kumagai, Taizo, Nakasu Kimihiro Nishimura, Masakazu Kobayashi

    Asia-Pacific Microwave Photonics Conference   (Kyoto) 

    発表年月: 2012年04月

     概要を見る

    PB-13

  • 近接昇華法によるAgGaTe2の成長

    宇留野 彩, 小林正和

    平成24年電気学会全国大会   (広島工業大学)  電気学会  

    発表年月: 2012年03月

  • ZnMgTe/ZnTe 導波路の結晶構造が及ぼす光学特性および結晶性の評価

    熊谷裕輝, 西村公宏, 中須大蔵, 小林正和

    第59回応用物理学関係連合講演会   (早稲田大学)  応用物理学会  

    発表年月: 2012年03月

  • c 面サファイア基板上のZnTe 薄膜の作製とドメインの構造の改善

    中須大蔵, 熊谷裕輝, 西村公宏, 小林正和

    第59回応用物理学関係連合講演会   (早稲田大学)  応用物理学会  

    発表年月: 2012年03月

  • 近接昇華法によるSi 基板上へのAgGaTe2の作製とストイキオメトリ制御

    宇留野彩, 小林正和

    第59回応用物理学関係連合講演会   (早稲田大学)  応用物理学会  

    発表年月: 2012年03月

  • ZnO Coated Nanoparticle Phosphors

    Masakazu Kobayashi  [招待有り]

    MRS Fall Meeting & Exhibit   (Boston MA) 

    発表年月: 2011年11月

     概要を見る

    M9.1

  • 外部電界が与えられたZnMgTe/ZnTe積層構造における偏光状態の解析

    熊谷裕輝, 小林正和

    第72回応用物理学会学術講演会   (山形大学)  応用物理学会  

    発表年月: 2011年08月

  • Growth of ZnMgTe/ZnTe Waveguide Structures and Analysis of the Light Polarization with the Electric Field

    Y. Kumagai, M. Kobayashi

    2011 International Conference on Solid State Devices and Materials   (Aichi Industry & Labor Center) 

    発表年月: 2011年08月

     概要を見る

    P-8-23

  • X-ray pole figure analysis of ZnTe layers grown on lattice mismatched substrates

    M.Kobayashi, Y. Kumagai, T.Baba, S.Imada

    15th International Conference on II-VI Compounds   (Mayan Riviera Mexico) 

    発表年月: 2011年08月

     概要を見る

    Thu-P24

  • Preparation of red phosphor nanoparticle films for the application to silicon solar cells

    Masakazu Kobayashi, AyakaYagi Miwa, Inaguma, SayakoHamaguchi

    Electronic Materials Conference   (Santa Barbara California) 

    発表年月: 2011年06月

     概要を見る

    N1

  • 赤色蛍光体ナノ粒子の透明薄膜作製とシリコン太陽電池への応用

    八木彩夏, 稲熊美和, 浜口紗也子, 小林正和

    平成23年電気学会全国大会   (大阪大学)  電気学会  

    発表年月: 2011年03月

     概要を見る

    2-112

  • Evaluation of influence by superimposed voltage of ZnMgTe/ZnTe waveguide

    熊谷 裕輝, 安藤, 佳祐, 中村, 玄, 長谷川, 輝, 小林 正和

    第58回応用物理学関係連合講演会 神奈川工業大学   (神奈川工業大学)  応用物理学会  

    発表年月: 2011年03月

     概要を見る

    27a-BQ-4

  • Cu2ZnSnS4ナノ粒子による薄膜作製

    浜口 紗也子, 野岡ゆかり, 小林 正和

    第58回応用物理学関係連合講演会   (神奈川工業大学)  応用物理学会  

    発表年月: 2011年03月

     概要を見る

    24a-KW-1

  • Growth of ZnMgTe/ZnTe waveguide structures on ZnTe (001) substrates by molecular beam epitaxy

    Y. Kumagai, S. Imada, T. Baba, M. Kobayashi

    The 16th International Conference on Molecular Beam Epitaxy   (Berlin Germany) 

    発表年月: 2010年08月

     概要を見る

    P3.18

  • SrGa2S4:Eu nanoparticle phosphors prepared by a ball milling method

    M. Kobayashi, S. Hamaguchi, T. Yamamoto

    World Congress on Particle Technology   (Nuremberg Germany) 

    発表年月: 2010年04月

  • X線回折を用いたSi(110)基板上のZnTeエピタキシャル膜の双晶ドメイン方位解析

    小林信太郎, 稲葉克彦, 紺谷貴之, 久保富活, 櫻澤 翔, 馬場俊彰, 今田将太, 小林正和

    第57回応用物理学関係連合講演会   (東海大学)  応用物理学会  

    発表年月: 2010年03月

     概要を見る

    19p-TW-6

  • ZnMgTe/ZnTe導波路構造の作製と低転位化への検討

    今田将太, 馬場俊彰, 太田匠哉, 熊谷裕輝, 木原大真, 小林正和

    第57回応用物理学関係連合講演会   (東海大学)  応用物理学会  

    発表年月: 2010年03月

     概要を見る

    19p-TW-5

  • 近赤外蛍光体Y3Al5O12:Ndナノ粒子の作製

    山本琢磨, 浜口紗也子, 小林正和

    第57回応用物理学関係連合講演会   (東海大学)  応用物理学会  

    発表年月: 2010年03月

     概要を見る

    18a-TF-2

  • サファイア基板上へのZnTe薄膜の作製と配向性の評価

    馬場俊彰, 今田将太, 木原大真, 熊谷裕輝, 太田匠哉, 小林正和

    平成22年電気学会全国大会   (明治大学)  電気学会  

    発表年月: 2010年03月

     概要を見る

    2-064

  • The Effects of Post-Annealing on the Crystallinity and the Optical Properties of SrGa2S4:Eu Nanoparticles

    S. Hamaguchi, R. Takeuchi, T. Yamamoto, M. Kobayashi

    The 16th International Display Workshops   (Miyazaki) 

    発表年月: 2009年12月

     概要を見る

    PHp - 16

  • X-ray Diffraction Studies of ZnMgTe/ZnTe Layered Structures and ZnTe/Si Structures

    M. Kobayashi, S. Imada, T. Baba, S. Sakurasawa

    2009 II-VI Workshop   (Chicago Illinois) 

    発表年月: 2009年10月

     概要を見る

    7.6

  • DOPED TERNARY COMPOUND NANOPARTICLES PHOSPHORS

    M.Kobayashi, S.Hamaguchi, T.Yamamoto

    4th Asian Particle Technology Symposium   (New Delhi India) 

    発表年月: 2009年09月

  • SrGa2S4:Euナノ粒子蛍光体を発光層に用いた薄膜EL素子(II)

    山下雄大, 大観光徳, 浜口紗也子, 小林正和

    第70回応用物理学会学術講演会   (富山大学)  応用物理学会  

    発表年月: 2009年09月

     概要を見る

    10a-TD-6

  • SrGa2S4:Euナノ粒子のH2Sアニールによる結晶性への影響

    浜口紗也子, 山本琢磨, 小林正和

    第70回応用物理学会学術講演会   (富山大学)  応用物理学会  

    発表年月: 2009年09月

     概要を見る

    9p-TD-8

  • Growth and characterization of ZnMgTe/ZnTe layered structures grown by molecular beam epitaxy

    S. Imada, T. Baba, S. Sakurasawa, M. Kobayashi

    The 14th International Conference on II-VI compounds   (Ioffe Institute of the Russian Academy of Sciences Saint-Petersburg Russia) 

    発表年月: 2009年08月

     概要を見る

    Mo5p-12

  • SrGa2S4:Eu ナノ粒子蛍光体を発光層に用いた薄膜EL素子

    山下雄大, 小谷剛史, 大観光徳, 浜口紗也子, 小林正和

    第56回応用物理学関係連合講演会   (筑波大学)  応用物理学会  

    発表年月: 2009年03月

     概要を見る

    31a-P8-10

  • SrGa2S4:Eu蛍光体ナノ粒子を用いた透明薄膜の作製

    浜口紗也子, 山本琢磨, 小林正和

    第56回応用物理学関係連合講演会   (筑波大学)  応用物理学会  

    発表年月: 2009年03月

     概要を見る

    31a-P8-5

  • 単一ウォールカーボンナノチューブの分散・微細化の検討

    加藤伸一郎, 石井亮太, 濱口沙也子, 小林正和, 宇高勝之

    第56回応用物理学関係連合講演会   (筑波大学)  応用物理学会  

    発表年月: 2009年03月

     概要を見る

    30a-TA-1

  • ZnMgTe/ZnTe積層薄膜の作製及び格子不整歪みの評価

    今田将太, 馬場俊彰, 桜沢翔, 小林正和

    第56回応用物理学関係連合講演会   (筑波大学)  応用物理学会  

    発表年月: 2009年03月

     概要を見る

    30p-J-3

  • 極点図測定によるZnTe(110)/Siの構造解析

    桜沢 翔, 馬場俊彰, 今田将太, 小林正和

    平成21年 電気学会全国大会   (北海道大学高等教育機能開発総合センター)  電気学会  

    発表年月: 2009年03月

     概要を見る

    2-082

  • Synthesis and optical characterization of ternary compound phosphor based core/shell nanoparticles

    Hamaguchi Sayako, Kobayashi Masakazu

    14th International Workshop on Inorganic and Organic Electroluminescence & 2008 International Conference on the Science and Technology of Emissive Displays and Lighting 2008   (Bagni di Tivoli Italy) 

    発表年月: 2008年09月

     概要を見る

    2-13-PO

  • Optical Property Characterization of Core/shell Nanoparticle Phosphor Materials Prepared by the Ball Milling Method

    M. Kobayashi, S. Hamaguchi

    International conference on nanoscience + technology   (Keystone CO USA) 

    発表年月: 2008年07月

     概要を見る

    NO2-TuA2

  • 硫化物系蛍光体ナノ粒子の光学的特性の改善

    浜口紗也子, 小林正和

    第55回応用物理学関係連合講演会   (日本大学)  応用物理学会  

    発表年月: 2008年03月

     概要を見る

    28p-ZD-15

  • Electrical Properties of Self-Cataltyic GaN Nanowires Grown by MBE

    C E Kendrick, M. Kobayashi, S. M. Durbin

    2008 International Conference On Nanoscience and Nanotechnology   (Melbourne Victoria Australia) 

    発表年月: 2008年02月

     概要を見る

    P56

  • Synthesis and optical characterization of ternary compound phosphor nanoparticles by the ball-milling method

    M. Kobayashi, S. Hamaguchi

    2008 International Conference On Nanoscience and Nanotechnology   (Melbourne Victoria Australia) 

    発表年月: 2008年02月

     概要を見る

    A1-1130

  • Novel PV device directly emitting laser beam using III-V materials for space solar power system

    K.Fujita, M.Kobayashi, H.Ohta, H.Furukawa, M.Niino

    17th International Photovoltaic Science and Engineering Conference   (Fukuoka International Congress Center) 

    発表年月: 2007年12月

  • Mechanisms in the formation of high quality Schottky contacts to n-type ZnO

    M.W. Allen, C.H. Swartz, M. Henseler, R.J. Reeves, J.B. Metso, H. Von Wenckstern, M. Grundmann, S.A. Hafiel, P.H. Jefferson, P.D.C. King, T.D. Veal, C. McConville, M. Kobayashi, S.M. Durbin

    Symposium L of the 2007 Fall Meeting of the Materials Research Society   (Boston MA) 

    発表年月: 2007年11月

  • Preparation of ZnS:Mn2+ and other sulphur compound nanoparticles by a ball-milling method

    Sayako Hamaguchi, Shinji Ishizaki, Masakazu Kobayashi

    13th INTERNATIONAL CONFERENCE ON II-VI COMPOUNDS   (Jeju Korea) 

    発表年月: 2007年09月

  • ボールミル法によるβ-FeSi2ナノ粒子の作製

    植村亮, 國本健太郎, 浜口紗也子, 小林正和

    第68回応用物理学会学術講演会   (北海道工業大学)  応用物理学会  

    発表年月: 2007年09月

     概要を見る

    5p-Q-11

  • ボールミル法による緑色・赤色蛍光体ナノ粒子の作製と光学的特性の評価

    浜口紗也子, 小林正和

    第68回応用物理学会学術講演会   (北海道工業大学)  応用物理学会  

    発表年月: 2007年09月

     概要を見る

    4a-L-5

  • 3D Branching GaN Nanowires

    C.E. Kendrick, R. Tilley, M. Kobayashi, S.M. Durbin

    Spring Meeting of the European Materials Research Society   (Strasbourg France) 

    発表年月: 2007年05月

  • ボールミル法を用いた3元系蛍光体ナノ粒子の作製

    浜口紗也子, 小林正和

    第54回応用物理学関係連合講演会   (青山学院大学(淵野辺キャンパス))  応用物理学会  

    発表年月: 2007年03月

     概要を見る

    30p-ZN-5

  • Preparation and characterization of II-VI compound nano-particles prepared by a ball milling method

    M.Kobayashi, S. Ishizaki, M. Uenishi

    Nanotech Insight 2007   (Luxor Egypt.) 

    発表年月: 2007年03月

  • GaN Nanotrees

    C.E. Kendrick, R. Tilley, M. Kobayashi, S.M. Durbin

    3rd International Conference on Advanced Materials and Nanotechnology   (Wellington New Zealand) 

    発表年月: 2007年02月

  • Electroluminescence from Single 3D GaN Nanowire Grown by Self-Catalytic Molecular Beam Epitaxy

    Chito E. Kendrick, R. Tilley, M. Kobayashi, R. J. Reeves, S. M. Durbin

    MRS fall meetings Symposium I: Advances in III-V Nitride Semiconductor Materials and Devices   (Boston MA) 

    発表年月: 2006年11月

     概要を見る

    I7.52

  • Self branching GaN nanowires

    C.E Kendrick, P.A. Anderson, R. Tilley, M. Kobayashi, S.M. Durbin

    14th International Conference on Molecular Beam Epitaxy   (Waseda University) 

    発表年月: 2006年09月

  • Al and N co-doped ZnTe Layers Grown by MBE

    A.Ichiba, M. Kobayashi

    14th International Conference on Molecular Beam Epitaxy   (Waseda University) 

    発表年月: 2006年09月

  • Self-assembling GaN branching nanowires

    C.E Kendrick, P.A. Anderson, P. Miller, R. Tilley, R.J. Reeves, M. Kobayashi, S.M. Durbin

    2006 International Conference On Nanoscience and Nanotechnology   (Brisbane Qld Australia) 

    発表年月: 2006年07月

  • Co-doping法によるZnTe:(Al,N)膜の成長と光学的特性の評価(?)

    一場綾, 天野優, 国政圭, 上野純, 小倉康平, 小林正和

    第53回応用物理学関係連合講演会   (武蔵工業大学(世田谷キャンパス))  応用物理学会  

    発表年月: 2006年03月

     概要を見る

    22p-ZH-8

  • Growth and Optical Property Characterizations of ZnTe:(Al、N) Layers Using a Co-doping Technique

    A. Ichiba, J, Ueno, K. Ogura, S. Katsuta, M. Kobayashi

    12th INTERNATIONAL CONFERENCE ON II-VI COMPOUNDS   (Warsaw University Warsaw Poland) 

    発表年月: 2005年09月

     概要を見る

    Thu-P-47

  • MBE Growth of ZnSe/MgCdS and ZnCdS/MgCdS Superlattices for UV-A Sensors

    J.Ueno K.Ogura, A.Ichiba S.Katsuta, M.Kobayashi, K.Onomitsu, Y.Horikoshi

    12th INTERNATIONAL CONFERENCE ON II-VI COMPOUNDS   (Warsaw University Warsaw Poland) 

    発表年月: 2005年09月

     概要を見る

    Thu-P-18

  • ボールミル法を用いて作製したドープ型ZnSナノ粒子の分散性の検討

    石崎慎治, 小林正和

    第66回応用物理学会学術講演会   (徳島大学常三島キャンパス)  応用物理学会  

    発表年月: 2005年09月

     概要を見る

    8a-K-1

  • II-VI compound nano-particles prepared by a ball milling method

    M.Kobayashi, S. Ishizaki, M. Uenishi

    International conference on nanomaterials NANO2005   (Mepco Schlenk College Sivakasi Tamil Nadu India) 

    発表年月: 2005年07月

  • GaAsエピタキシャル膜上へのZnCdS/MgCdS超格子の作製とUVAセンサ応用

    上野純, 勝田昇平, 一場綾, 小倉康平, 小林正和

    第52回応用物理学関係連合講演会   (埼玉大学(埼玉県さいたま市))  応用物理学会  

    発表年月: 2005年03月

     概要を見る

    31p-ZN-2

  • 太陽光励起半導体レーザの反射防止構造の検討

    岩井亮, 小倉康平, 小林正和, 藤田和久, 新野正之, 太田浩一, 古川裕之, 犬塚博誠

    第52回応用物理学関係連合講演会   (埼玉大学(埼玉県さいたま市))  応用物理学会  

    発表年月: 2005年03月

     概要を見る

    31p-ZH-9

  • 太陽光励起半導体レーザ構造の光吸収・発光特性評価

    小倉康平, 岩井亮, 小林正和, 藤田和久, 新野正之, 太田浩一, 古川裕之, 犬塚博誠

    第52回応用物理学関係連合講演会   (埼玉大学(埼玉県さいたま市))  応用物理学会  

    発表年月: 2005年03月

     概要を見る

    31p-ZH-8

  • Co-doping法によるZnTe:(Al、N)膜の成長と光学的特性の評価

    一場綾, 勝田昇平, 上野純, 小倉康平, 小林正和

    第52回応用物理学関係連合講演会   (埼玉大学(埼玉県さいたま市))  応用物理学会  

    発表年月: 2005年03月

     概要を見る

    31a-ZN-6

  • Preparation of SrS:Ce/ZnO core-shell nanoparticles using reverse micelle method

    Yusuke Kusakari, Shinji Ishizaki, Masakazu Kobayashi

    2004 MRS fall meetings Symposium B: Progress in Semiconductor Materials IV ? Electronic and Optoelectronic Applications   (Boston MA) 

    発表年月: 2004年11月

     概要を見る

    B10.2

  • Fabrication of ZnO Coated ZnS:Mn2+ Nanoparticles

    Shinji Ishizaki Yusuke Kusakari, Masakazu Kobayashi

    2004 MRS fall meetings Symposium B: Progress in Semiconductor Materials IV ? Electronic and Optoelectronic Applications   (Boston MA) 

    発表年月: 2004年11月

     概要を見る

    B2.22

  • 太陽光励起半導体レーザーの開発

    藤田和久, 小林正和, 古河裕之, 太田浩一, 犬塚博誠

    第48回宇宙科学技術連合講演会   (フェニックス・プラザ(福井県福井市田原)) 

    発表年月: 2004年11月

     概要を見る

    1B12

  • 分光画像法によるヒト気管支自家蛍光の解析−その2−

    鮫島冴映子, 神保直樹, 小林正和

    平成16年 電気学会 電子・情報・システム部門大会   (宇都宮大学)  電気学会  

    発表年月: 2004年09月

     概要を見る

    GS3-3

  • 逆ミセル法を用いたSrS:Ce/ZnOナノ粒子の作製と光学的特性の評価

    草刈勇介, 小林正和

    第65回応用物理学会学術講演会   (東北学院大学)  応用物理学会  

    発表年月: 2004年09月

     概要を見る

    3a-ZL-5

  • 太陽光励起半導体レーザに適したレーザ構造の検討-クラッド層の設計-

    岩井 亮, 小倉康平, 小林正和, 藤田和久, 新野正之, 太田浩一, 古河裕之, 犬塚博誠

    第65回応用物理学会学術講演会   (東北学院大学)  応用物理学会  

    発表年月: 2004年09月

     概要を見る

    1a-ZN-24

  • Growth and UV-A sensor applications of MgCdS/ZnCdS superlattices

    M. Kobayashi, M. Enami J, Ueno, S. Katsuta, A. Ichiba

    The 13th International Conference on Molecular Beam Epitaxy (MBE 2004) Conference   (Edinburgh Scotland)  Centre at Heriot-Watt University  

    発表年月: 2004年08月

     概要を見る

    TuA2.4

  • 分光画像法によるヒト気管支自家蛍光の解析

    鮫島, 冴映子, 小林, 正和

    平成16年電気学会全国大会   (青山学院大学 相模原キャンパス)  電気学会  

    発表年月: 2004年03月

     概要を見る

    3-007

  • ボールミル法を用いたCdSe/ZnOナノ粒子の作製と応用

    上西正晃, 石崎慎治, 小林正和

    2004年春季応用物理学関係連合講演会   (東京工科大学)  応用物理学会  

    発表年月: 2004年03月

     概要を見る

    29p-P13-2

  • 顕微FT-IRによるヒト気管支組織の構造評価

    上田 泰央, 鮫島 冴映子, 小林 正和

    2004年春季応用物理学関係連合講演会   (東京工科大学)  応用物理学会  

    発表年月: 2004年03月

     概要を見る

    29p-K-16

  • Planar-doping法によるn-ZnTe:Al膜の成長

    堤一陽, 勝田昇平, 榎並正晃, 廣瀬文昭, 小林正和

    2004年春季応用物理学関係連合講演会   (東京工科大学)  応用物理学会  

    発表年月: 2004年03月

     概要を見る

    29p-P12-7

  • 逆ミセル法によるSrSナノ粒子の作製

    草刈勇介, 小林正和

    2004年春季応用物理学関係連合講演会   (東京工科大学)  応用物理学会  

    発表年月: 2004年03月

     概要を見る

    29p-P13-1

  • ZnTeホモエピタキシャル層上へ作製されたCdS量子ドットの光学的特性

    勝田昇平, 堤一陽, 榎並正晃, 廣瀬文昭, 小林正和

    2004年春季応用物理学関係連合講演会   (東京工科大学)  応用物理学会  

    発表年月: 2004年03月

     概要を見る

    29p-P12-8

  • ボールミル法によるZnS:Mn2+ナノ粒子の作製と評価

    石崎慎治, 上西正晃, 小林正和

    2004年春季応用物理学関係連合講演会   (東京工科大学)  応用物理学会  

    発表年月: 2004年03月

     概要を見る

    29p-P13-3

  • MBE法によるZnCdS/MgCdS超格子の作製と応用

    榎並正晃, 上野純, 廣瀬文昭, 堤一陽, 勝田昇平, 小林正和

    2004年春季応用物理学関係連合講演会   (東京工科大学)  応用物理学会  

    発表年月: 2004年03月

     概要を見る

    29p-P12-9

  • 太陽光励起半導体レーザーの設計コードの開発

    古河裕之, 藤田和久, 太田浩一, 小林正和, 新野正之

    レーザー学会創立30周年記念 学術講演会第24回年次大会   (仙台国際センター)  レーザー学会  

    発表年月: 2004年01月

  • 太陽光励起半導体レーザーの試作

    藤田和久, 太田浩一, 小林正和, 水井順一, 犬塚博誠, 古河裕之, 山中正宣, 新野正之

    レーザー学会創立30周年記念 学術講演会第24回年次大会   (仙台国際センター)  レーザー学会  

    発表年月: 2004年01月

  • 分光画像解析法によるヒト気管支の自家蛍光測定

    鮫島冴子, 小林正和, 渋谷 潔, 星野 英久, 千代 雅子, 藤沢 武彦

    第24回日本レーザー医学会総会   (長良川国際会議場(岐阜市))  日本レーザー医学会  

    発表年月: 2003年11月

  • MBE growth of ZnMgCdS compounds on (001) GaAs for UV-A sensors

    M. ENAMI K. TSUTSUMI, F, HIROSE S. KATSUTA, M. KOBAYASHI

    11th International Conference on II-VI Compounds   (Niagara Falls New York) 

    発表年月: 2003年09月

  • 太陽光励起半導体レーザーの開発

    藤田和久, 太田浩一, 水井順一, 古河裕之, 小林正和, 山中正宣, 新野正之

    第64回応用物理学会学術講演会   (福岡大学(七隈キャンパス))  応用物理学会  

    発表年月: 2003年08月

     概要を見る

    31a-YC-1

  • 生体内の酸類がelastin・desmosineの光学的特性に与える影響の検討

    上田泰央, 小林正和

    第64回応用物理学会学術講演会   (福岡大学(七隈キャンパス))  応用物理学会  

    発表年月: 2003年08月

     概要を見る

    31a-Q-8

  • ボールミル法を用いたCdSe/ZnOナノ粒子の作製と光学的特性の評価

    上西正晃, 草刈勇介, 小林正和

    第64回応用物理学会学術講演会   (福岡大学(七隈キャンパス))  応用物理学会  

    発表年月: 2003年08月

     概要を見る

    2a-ZE-1

  • ZnMgCdS4元混晶の組成制御とUVAセンサの分光感度特性の評価

    榎並正晃, 廣瀬文昭, 堤 一陽, 勝田昇平, 小林正和

    第64回応用物理学会学術講演会   (福岡大学(七隈キャンパス))  応用物理学会  

    発表年月: 2003年08月

     概要を見る

    30p-B-10

  • Zn分子線支援原子状水素処理による(001)ZnTe基板の前処理とCdS量子ドットの作製

    堤一陽, 寺門洋, 榎並正晃, 勝田昇平, 廣瀬文昭, 小林正和

    第50回応用物理学関係連合講演会   (神奈川大学(横浜キャンパス))  応用物理学会  

    発表年月: 2003年03月

     概要を見る

    29p-x-10

  • UVAセンサ用ZnMgCdS 4元混晶の作製

    榎並正晃, 廣瀬文昭, 寺門洋, 堤一陽, 勝田昇平, 小林正和

    第50回応用物理学関係連合講演会   (神奈川大学(横浜キャンパス))  応用物理学会  

    発表年月: 2003年03月

     概要を見る

    29p-x-3

  • ボールミル法を用いたCdSe/ZnOナノ粒子の作製

    陰山孔貴, 上西正晃, 草刈勇介, 小林正和

    第50回応用物理学関係連合講演会   (神奈川大学(横浜キャンパス))  応用物理学会  

    発表年月: 2003年03月

     概要を見る

    28a-ZA-1

  • Low Temperature Treatment of the (001) ZnTe Substrate Surface with the Assist of Atomic Hydrogen

    K. Tsutsumi, H. Terakado, M. Enami, M. Kobayashi

    30th Conference on the Physics and Chemistry of Semiconductor Interfaces   (Salt Lake City Utah) 

    発表年月: 2003年01月

  • ポルフィリン化合物の添加がElastin・NADHの自家蛍光特性へ与える影響の検討

    上田泰央, 小林正和

    第63回応用物理学会学術講演会   (新潟大学)  応用物理学会  

    発表年月: 2002年09月

     概要を見る

    26p-ZK-9

  • 原子状水素処理による(100)ZnTe基板の前処理とホモエピタキシャル膜の作製

    堤 一陽, 寺門, 洋, 榎並正晃, 小林正和

    第63回応用物理学会学術講演会   (新潟大学)  応用物理学会  

    発表年月: 2002年09月

     概要を見る

    26p-YE-3

  • 乳酸添加が生体内自家蛍光物質の光学的特性へ与える影響の検討

    上田泰央, 小林正和

    第49回応用物理学関係連合講演会   (東海大学(神奈川))  応用物理学会  

    発表年月: 2002年03月

     概要を見る

    28a-Q-3

  • 分光画像解析システムによる生体材料の自家蛍光評価

    澤田 理奈, 小林雄, 小林正和

    第49回応用物理学関係連合講演会   (東海大学(神奈川))  応用物理学会  

    発表年月: 2002年03月

     概要を見る

    28a-Q-2

  • 紫外線レーザダイオードを用いたヒト気管支の自発蛍光測定

    小林正和, 渋谷潔, 星野英久, 藤澤武彦

    第48回応用物理学関係連合講演会   (明治大学)  応用物理学会  

    発表年月: 2002年03月

  • ZnTe基板のSe熱拡散によるZnSe/ZnSeTe/ZnTe構造の形成

    寺門洋, 澤田理奈, 小林正和

    第62回応用物理学会学術講演会   (愛知工業大学(豊田市))  応用物理学会  

    発表年月: 2001年09月

     概要を見る

    12a-P6-8

  • Diffusion Profiles of Se in the bulk ZnTe

    M. Kobayashi, H. Terakado, R. Sawada, A. Arakawa, K. Sato

    10 TH INTERNATIONAL CONFERENCE ON II-VI COMPOUNDS   (BREMEN GERMANY) 

    発表年月: 2001年09月

  • Autofluorescence Spectroscopy Analysis of the Human Bronchus using a UV Laser Diode

    M. Kobayashi, K. Shibuya, H. Hoshino, T. Fujisawa

    14TH WORLD CONGRESS OF THE INTERNATIONAL SOCIETY FOR LASER SURGERY AND MEDICINE   (CHENNAI MADRAS INDIA) 

    発表年月: 2001年08月

  • 紫外線レーザダイオードによるヒト気管支の自発蛍光スペクトル測定

    小林正和, 渋谷潔, 星野英久, 藤澤武彦

    第24回日本気管支学会総会   (幕張)  日本気管支学会  

    発表年月: 2001年05月

     概要を見る

    P-60

  • 半導体レーザダイオードを用いたヒト気管支組織の蛍光特性評価

    小林正和, 渋谷潔, 星野英久, 藤澤武彦

    平成13年度日本分光学会春季講演会   (早稲田大学)  日本分光学会  

    発表年月: 2001年05月

  • CdS based novel light emitting device structures grown by MBE

    M.Kobayashi, K. Kitamura, H. Umeya, A. W. Jia, A. Yoshikawa, M. Shimotomai, Y. Kato, K. Takahashi

    3rd International Symposium on Blue laser and Light Emmitting Diodes   (Berlin Germany) 

    発表年月: 2000年03月

  • Cross-Sectional Scanning Tunneling Microscopy Characterization of Cubic GaN Epilayers Grown on (001) GaAs

    T. Kazama, F, Yasunaga, Y. Taniyasu, A. Jia, Y. Kato, M. Kobayashi, A. Yoshikawa, K. Takahashi

    3rd International Symposium on Blue laser and Light Emmitting Diodes   (Berlin Germany) 

    発表年月: 2000年03月

  • Cubic InGaN/GaN Double-Heterostructure Light Emitting Diodes Grown on GaAs (001) Substrates by MOVPE

    Y. Taniyasu, K. Suzuki, D.H. Lim, A. Jia, M.Shimotomai, Y. Kato, M. Kobayashi, A. Yoshikawa, K. Takahashi

    3rd International Symposium on Blue laser and Light Emmitting Diodes   (Berlin Germany) 

    発表年月: 2000年03月

  • Growth of hexagonal ZnCdS on GaAs (111)B and (001) substrates by MBE

    H. Umeya, K. Kitamura, A. W. Jia, M. Kobayashi, A. Yoshikawa, M. Shimotomai, Y. Kato, K. Takahashi

    International Conference on II-VI Compounds   (Kyoto) 

    発表年月: 1999年11月

  • Self-assembled CdS quantum dot structures grown on ZnSe and ZnSSe

    K. Kitamura, H. Umeya, A. W. Jia, M. Kobayashi, A. Yoshikawa, M. Shimotomai, Y. Kato, K. Takahashi

    International Conference on II-VI Compounds   (Kyoto) 

    発表年月: 1999年11月

  • Design of new UV/blue/green light emitters made of hexagonal-phase ZnMgCdOSSe mixed-crystal system fabricated on GaAs- and InP-(111) substrates

    A. Jia, T. Furushima M. Kobayashi, Y. Kato, M, Shimotomai, A. Yoshikawa, K. Takahashi

    International Conference on II-VI Compounds   (Kyoto) 

    発表年月: 1999年11月

  • Spectroscopy of self-assembled quantum dots in ZnSe

    H. Zhou, A.V. Nurmikko, M. Kobayashi, A. Yoshikawa

    Conference on Lasers and Electro-Optics /Quantum Electronins and Laser Science Conference   (Baltimore) 

    発表年月: 1999年05月

  • MOVPE法による立方晶InGaN/GaNヘテロ構造の作製

    谷保芳孝, 佐藤英史, 佐藤弘人, 渡邊泰弘, 下山紀夫, 賈岸偉, 下斗米道夫, 加藤嘉則, 小林正和, 吉川明彦, 高橋清

    第46回応用物理学関係連合講演会   (野田)  応用物理学会  

    発表年月: 1999年03月

     概要を見る

    30p-M-4

  • 窒素供給方向に起因したMBE成長立方晶GaNの結晶軸の傾き

    林秀樹, 林田章裕, 秦志新, 賈岸偉, 下斗米道夫, 加藤嘉則, 小林正和, 吉川明彦, 高橋清

    第46回応用物理学関係連合講演会   (野田)  応用物理学会  

    発表年月: 1999年03月

     概要を見る

    30a-N-4

  • ZnO透明導電膜上への多結晶GaN成長

    渡邊泰弘, 谷保芳孝, 佐藤英史, 佐藤弘人, 辻隆志, 賈岸偉, 下斗米道夫, 加藤嘉則, 小林正和, 吉川明彦, 高橋清

    第46回応用物理学関係連合講演会   (野田)  応用物理学会  

    発表年月: 1999年03月

     概要を見る

    30a-M-3

  • MOVPE法によるGaAs(111)基板上への六方晶ZnCdSの成長及び立方晶混在比低減化の検討

    古島達弥, 河内福賢, 賈岸偉, 下斗米道夫, 加藤嘉則, 小林正和, 吉川明彦, 高橋清

    第46回応用物理学関係連合講演会   (野田)  応用物理学会  

    発表年月: 1999年03月

     概要を見る

    28p-Q-14

  • MBE法によるGaAs(001), (111)基板上へのZnCdSの成長と評価および六方晶相の混在の検討

    梅谷治樹, 中村眞一郎, 北村和也, 賈岸偉, 下斗米道夫, 加藤嘉則, 小林正和, 吉川明彦, 高橋清

    第46回応用物理学関係連合講演会   (野田)  応用物理学会  

    発表年月: 1999年03月

     概要を見る

    28p-Q-13

  • CdS自己構築量子ドットLEDの輝度特性の制御

    中村眞一郎, 北村和也, 梅谷治樹, 賈岸偉, 下斗米道夫, 加藤嘉則, 小林正和, 吉川明彦, 高橋清

    第46回応用物理学関係連合講演会   (野田)  応用物理学会  

    発表年月: 1999年03月

     概要を見る

    28a-Q-9

  • ZnSxSe1-x (001)上へのCdS自己構築量子ドットの作製及び評価

    北村和也, 中村眞一郎, 梅谷治樹, 賈岸偉, 下斗米道夫, 加藤嘉則, 小林正和, 吉川明彦, 高橋清

    第46回応用物理学関係連合講演会   (野田)  応用物理学会  

    発表年月: 1999年03月

     概要を見る

    28a-Q-8

  • MBE法による高品質六方晶GaNエピ膜の成長

    勝康夫, 有馬茂幸, 林田章裕, 林秀樹, 木村龍平, 秦志新, 賈岸偉, 下斗米道夫, 加藤嘉則, 小林正和, 吉川明彦, 高橋清

    第46回応用物理学関係連合講演会   (野田)  応用物理学会  

    発表年月: 1999年03月

     概要を見る

    28p-L-7

  • Electron-Hole Dynamics in CdS Self-Assembled Quantum Dots on ZnSe

    H. Zhou, A.V. Nurmikko, M. Kobayashi, A. Yoshikawa

    American Physical Society Centennial Meeting Program   (Atlanta) 

    発表年月: 1999年03月

  • Luminescence properties of CdS quantum dots on ZnSe

    M. Kobayashi, S. Nakamura, K. Kitamura, H. Umeya, A. Jia, M. Kobayashi, A. Yoshikawa, M. Shimotomai, Y. Kato

    26th Conference on Physics and Chemistry of Semiconductor Interfaces   (San Diego USA) 

    発表年月: 1999年01月

  • A study on initial nucleation using an ultra thin amorphous buffer layer for the growth of GaN on Al2O3 (0001) by molecular beam epitaxy

    R. Kimura, K. Takahashi, A. W. Jia, M. Kobayashi, A. Yoshikawa

    2nd International Symposium on Blue laser and Light Emitting Diodes   (Kisarazu Chiba) 

    発表年月: 1998年09月

  • Study on initial growth stage of device-quality cubic GaN on (001) GaAs by RHEED and AFM: the nitridation and buffer-layer deposition processes in MBE

    H. Hayashi, A. Hayashida, Y. Sugure, Z. Qin, A, W. Jia, M. Kobayashi, M. Shimotomai, Y. Kato, A. Yoshikawa, K. Takahashi

    2nd International Symposium on Blue laser and Light Emitting Diodes   (Kisarazu Chiba) 

    発表年月: 1998年09月

  • In-Situ Monitoring of the Surface Kinetics of the Cubic GaN Films in MOVPE Using Spectroscopic Ellipsometry

    Y. Taniyasu, E. Sato, H. Sato, N. Shimoyama, A. W. Jia, M. Shimotomai, Y. Kato, M. Kobayashi, A. Yoshikawa, K. Takahashi

    2nd International Symposium on Blue laser and Light Emitting Diodes   (Kisarazu Chiba) 

    発表年月: 1998年09月

  • Effect of V/III source-sully ratio on the crystalline-structure quality of the cubic GaN epilayer grown on (001) GaAs by MBE

    Z. Qin, H. Nagano, Y. Sugure, A. Jia, M. Kobayashi, Y. Kato, A. Yoshikawa, K. Takahashi

    2nd International Symposium on Blue laser and Light Emitting Diodes   (Kisarazu Chiba) 

    発表年月: 1998年09月

  • MBE成長によるZnSe再成長層界面の結晶性の改善

    梅谷治樹, 中村眞一郎, 北村和也, 賈岸偉, 下斗米道夫, 加藤嘉則, 小林正和, 吉川明彦, 高橋清

    第59回応用物理学術講演会   (広島)  応用物理学会  

    発表年月: 1998年09月

     概要を見る

    18a-YM-6

  • MBE法による高品質立方晶GaN成長の高速化・厚膜化の検討

    林田章裕, 勝康夫, 秦志新, 林秀樹, 賈岸偉, 下斗米道夫, 加藤嘉則, 小林正和, 吉川明彦, 高橋清

    第59回応用物理学術講演会   (広島)  応用物理学会  

    発表年月: 1998年09月

     概要を見る

    17p-YB-5

  • MOVPE法によるAlGaN成長のその場観察

    佐藤英史, 谷保芳孝, 佐藤弘人, 渡邊泰弘, 下山紀夫, 賈岸偉, 下斗米道夫, 加藤嘉則, 小林正和, 吉川明彦, 高橋清

    第59回応用物理学術講演会   (広島)  応用物理学会  

    発表年月: 1998年09月

     概要を見る

    17p-YA-2

  • 分光エリプソメトリーを用いた立方晶AlGaNおよびInGaNのMOVPE成長過程のその場観察

    谷保芳孝, 佐藤英史, 佐藤弘人, 下山紀夫, 賈岸偉, 下斗米道夫, 加藤嘉則, 小林正和, 吉川明彦, 高橋清

    第59回応用物理学術講演会   (広島)  応用物理学会  

    発表年月: 1998年09月

     概要を見る

    17a-YA-11

  • ZnSe(001)上CdS自己構築量子ドットの青色発光特性

    中村眞一郎, 北村和也, 梅谷治樹, 賈岸偉, 下斗米道夫, 加藤嘉則, 小林正和, 吉川明彦, 高橋清

    第59回応用物理学術講演会   (広島)  応用物理学会  

    発表年月: 1998年09月

     概要を見る

    16a-YL-1

  • ZnO透明導電膜上への多結晶GaNのMOVPE成長

    渡邊泰弘, 谷保芳孝, 佐藤英史, 佐藤弘人, 下山紀夫, 辻隆志, 賈岸偉, 加藤嘉則, 小林正和, 吉川明彦, 高橋清

    第59回応用物理学術講演会   (広島)  応用物理学会  

    発表年月: 1998年09月

     概要を見る

    15a-YC-4

  • Homoepitaxy of ZnSe on the citric acid etched (001) ZnSe Surface

    M. Kobayashi, K. Wakao, S. Nakamura, Y. Sugure, A. W. Jia, A. Yoshikawa, M. Shimotomai, Y. Kato, K. Takahashi

    Tenth International Conference on Molecular Beam Epitaxy   (Canne France) 

    発表年月: 1998年08月

  • Al2O3上へのh-GaNのMBE成長(2):成長初期過程のエピ層へ与える影響

    木村龍平, 高橋清, 勝康夫, 永野元, 秦志新, 賈岸偉, 小林正和, 吉川明彦

    第45回応用物理学関係連合講演会   (八王子)  応用物理学会  

    発表年月: 1998年03月

     概要を見る

    30a-ZP-7

  • ZnSe(001)上へのCdS自己構築量子ドットの光学的特性

    中村眞一郎, 若尾和弘, 賈岸偉, 下斗米道夫, 加藤嘉則, 小林正和, 吉川明彦, 高橋清

    第45回応用物理学関係連合講演会   (八王子)  応用物理学会  

    発表年月: 1998年03月

     概要を見る

    30a-ZN-9

  • 分光エリプソメトリーを用いた立方晶GaN成長表面のその場観察

    谷保芳孝, 佐藤英史, 佐藤弘人, 下山紀夫, 賈岸偉, 下斗米道夫, 加藤嘉則, 小林正和, 吉川明彦, 高橋清

    第45回応用物理学関係連合講演会   (八王子)  応用物理学会  

    発表年月: 1998年03月

     概要を見る

    29p-ZP-14

  • 立方晶GaNのGaAs(001)上へ成長における原子状水素のサーファクタント効果

    秦志新, 永野元, 勝康夫, 賈岸偉, 下斗米道夫, 加藤嘉則, 小林正和, 吉川明彦, 高橋清

    第45回応用物理学関係連合講演会   (八王子)  応用物理学会  

    発表年月: 1998年03月

     概要を見る

    29p-ZP-11

  • GaNバッファ層成長条件が立方晶GaNエピ層の表面平坦性に与える影響

    永野元, 勝康夫, 秦志新, 賈岸偉, 下斗米道夫, 加藤嘉則, 小林正和, 吉川明彦, 高橋清

    第45回応用物理学関係連合講演会   (八王子)  応用物理学会  

    発表年月: 1998年03月

     概要を見る

    29p-ZP-10

  • クエン酸水溶液を用いたZnSeのエッチングとZnSe/ZnSe界面の評価

    若尾和弘, 中村眞一郎, 賈岸偉, 下斗米道夫, 加藤嘉則, 小林正和, 吉川明彦, 高橋清

    第45回応用物理学関係連合講演会   (八王子)  応用物理学会  

    発表年月: 1998年03月

     概要を見る

    28p-ZN-2

  • A New In-situ Optical Probing Method with an Atomic Scale Resolution for Thin Film Deposition: Surface Photo-Interference (SPI )

    Y. Nakamura, T, Yamashita, M. Kobayashi, Y. Kato, A. Yoshikawa

    1995 Japan International Electronic Manufacturing Technology Symposium   (Omiya Japan) 

    発表年月: 1995年12月

  • Phase Instability of n-CdS Grown by MBE

    T. Yamada, C. Setiagung, A.W. Jia, M. Kobayashi, A. Yoshikawa

    15th Annual North American Conference on Molecular Beam Epitaxy   (Maryland USA) 

    発表年月: 1995年09月

  • MBE法によるZnS/CdSおよびZnS/CdS/ZnSe超格子の作製

    C. Setiagung, 山田剛, 賈岸偉, 小林正和, 吉川明彦

    第56回応用物理学会学術講演会   (富山)  応用物理学会  

    発表年月: 1995年08月

     概要を見る

    29a-W-2

  • MOVPE成長ZnSeへのTANを用いた窒素ドーピングの検討

    田中由紀夫, 小松茂樹, 伊藤良一, 小林正和, 吉川明彦

    第56回応用物理学会学術講演会   (富山)  応用物理学会  

    発表年月: 1995年08月

     概要を見る

    27p-W-11

  • 分光表面光干渉法によるZnSeのMOMBE成長過程のその場観察(2)

    中村豊, 山下寿康, 小林正和, 吉川明彦

    第56回応用物理学会学術講演会   (富山)  応用物理学会  

    発表年月: 1995年08月

     概要を見る

    27p-W-5

  • 立方晶、六方晶CdSのGaAs(100)基板上へのMBE成長

    山田剛, C. Setiagung, 賈岸偉, 小林正和, 吉川明彦

    第56回応用物理学会学術講演会   (富山)  応用物理学会  

    発表年月: 1995年08月

     概要を見る

    27a-W-3

  • Real Time Monitoring of Growth and p-type Doping Process in Ar Ion Laser-Assisted MOVPE of ZnSe

    M. Miyaji, Y. Ohira, S. Komatsu, M. Kurihara, N. Shimoyama, M. Kobayashi, Y. Kato, A. Yoshikawa

    7th International Conference on II-VI Compounds and Devices   (Edinburgh UK) 

    発表年月: 1995年08月

  • Reduction of p-ZnTe/p-ZnSe Valence Band Discontinuity by a Ga2Se3 Interfacial Layer

    T. Yoshida T, Nagatake, M. Kobayashi, A. Yoshikawa

    7th International Conference on II-VI Compounds and Devices   (Edinburgh UK) 

    発表年月: 1995年08月

  • MBE Growth of ZnTe/ZnSe Heterojunction with (Ga,Se) Interfacial Layer and Reduction of Band Discontinuity

    T. Yoshida, T. Kurusu, M. Kobayashi, A. Yoshikawa

    14th Electronic Materials Symposium   (IzuNagaoka Japan) 

    発表年月: 1995年07月

  • Formation of a Thin III-VI Compound Interfacial Layer at ZnTe/ZnSe Heterojunction and Its Effect on Energy Band Discontinuity

    T. Yoshida T, Nagatake, M. Kobayashi, A. Yoshikawa

    37th Electric Materials Conference   (Virginia USA) 

    発表年月: 1995年06月

  • ZnSe/ZnTeヘテロ界面の制御II

    吉田孝, 長竹剛, 村口昭一, 来栖武志, 小林正和, 吉川明彦

    第42回応用物理学関係連合講演会   (神奈川)  応用物理学会  

    発表年月: 1995年03月

     概要を見る

    30p-ZX-7

  • MBE成長p型ZnSe:Nのドナーアクセプタペア発光特性の評価 II

    高橋政志, 古山俊行, 小林正和, 吉川明彦

    第42回応用物理学関係連合講演会   (神奈川)  応用物理学会  

    発表年月: 1995年03月

     概要を見る

    29p-ZX-12

  • S単体を原料としたCdSのMBE成長とドーピング

    賈岸偉, 山田剛, 伊福徹, C. Setiagung, 小林正和, 吉川明彦

    第42回応用物理学関係連合講演会   (神奈川)  応用物理学会  

    発表年月: 1995年03月

     概要を見る

    29a-ZX-8

  • 分光表面光干渉法によるZnSeのMOMBE成長過程のその場観察

    中村豊, 秋葉学, 小林正和, 吉川明彦

    第42回応用物理学関係連合講演会   (神奈川)  応用物理学会  

    発表年月: 1995年03月

     概要を見る

    28p-ZX-6

  • MBE growth of sulfur-based binary and ternary widegap II-VI alloys using elemental sulfur source

    An W. Jia, T, Yamada, Masakazu Kobayashi, Akihiko Yoshikawa

    European workshop on II-VI compounds   (Linz Austria) 

    発表年月: 1994年09月

  • Theoretical Approach to 460nm ZnCdSSe Laser Diodes

    W. Imajuku, M. Takahashi, M. Kobayashi, A. Yoshikawa

    Intn'l Workshop on Metastable and Strained Semiconductor Structures   (Tsukuba Japan) 

    発表年月: 1994年09月

  • 高濃度アクセプタドーピングの現状と問題点

    小林 正和

    第55回応用物理学会学術講演会   (名古屋)  応用物理学会  

    発表年月: 1994年09月

     概要を見る

    21p-MC-1

  • ZnSe/ZnTeヘテロ界面の制御

    吉田 孝, 長竹 剛, 小林 正和, 吉川 明彦

    第55回応用物理学会学術講演会   (名古屋)  応用物理学会  

    発表年月: 1994年09月

     概要を見る

    21a-MB-2

  • S単体を原料としたMBE法によるS系二元化合物およびSリッチ混晶膜の成長

    賈 岸偉, 山田剛, 小林正和, 吉川明彦

    第55回応用物理学会学術講演会   (名古屋)  応用物理学会  

    発表年月: 1994年09月

     概要を見る

    19p-MB-5

  • Observation of a new in-situ optical monitoring signal with monolayer resolution in MOMBE and MOVPE of widegap II-VI compounds

    A. Yoshikawa, M. Kobayashi, S. Tokita

    7th International Conference on Metalorganic Vapor Phase Epitaxy   (Yokohama Japan) 

    発表年月: 1994年05月

  • Surface reaction mechanism in MOMBE-ALE of ZnSe and CdSe as Determined by a new in-situ optical probing method

    A. Yoshikawa, M. Kobayashi, S. Tokita

    3rd International Symposium on Atomic layer epitaxy and related surface processes   (Sendai Japan) 

    発表年月: 1994年05月

  • Acceptor Concentration Control of p-ZnSe Using N2+He Gas Plasma by Molecular Beam Epitaxy

    M. Kobayashi, A. Yoshikawa  [招待有り]

    Materials Research Society Meeting   (San Francisco CA) 

    発表年月: 1994年04月

  • ZnSe量子井戸レーザの活性層歪が動作特性に及ぼす影響

    今宿亙, 小林正和, 吉川明彦

    第41回応用物理学関係連合講演会   (神奈川)  応用物理学会  

    発表年月: 1994年03月

     概要を見る

    30a-W-2

  • MBE成長p型ZnSe:Nのドナーアクセプターペア発光特性の評価

    高橋政志, 小林正和, 吉川明彦

    第41回応用物理学関係連合講演会   (神奈川)  応用物理学会  

    発表年月: 1994年03月

     概要を見る

    29a-W-7

  • 表面光干渉法によるCdSeのMOMBE成長過程のその場観察

    時田茂, 小林正和, 吉川明彦

    第41回応用物理学関係連合講演会   (神奈川)  応用物理学会  

    発表年月: 1994年03月

     概要を見る

    28p-W-2

  • A New In-situ Optical Monitoring Method for the Surface Reaction in Photo-Excited Heteroepitaxy of Compound Semiconductors

    A. Yoshikawa, M. Kobayashi, S. Tokita, K. Sato

    1st International Conference on Photo-Excited Processes and Applications   (Sendai Japan) 

    発表年月: 1993年10月

  • 室温で460nm発振を可能にするZnCdSSeレーザ構造としきい値電流密度

    今宿亙, 小林正和, 吉川明彦

    第54回応用物理学会学術講演会   (北海道)  応用物理学会  

    発表年月: 1993年09月

     概要を見る

    30p-HB-6

  • (N2+He)混合プラズマドーピングによるp-ZnSSeのMBE成長

    長竹剛, 登坂裕之, 小林正和, 吉川明彦

    第54回応用物理学会学術講演会   (北海道)  応用物理学会  

    発表年月: 1993年09月

     概要を見る

    29p-ZL-14

  • p-ZnSeの高濃度ドーピング

    小林正和, 吉川明彦

    第54回応用物理学会学術講演会   (北海道)  応用物理学会  

    発表年月: 1993年09月

     概要を見る

    27a-HC-5

  • New In-situ Optical Probing Method in Heteroepitaxy: Surface Photo-Interference (SPI) and Its Application to the Study of ZnSe MOMBE Growth Process

    A. Yoshikawa, M. Kobayashi, S. Tokita

    3rd Japan-Korea Joint Symposium on Advanced Science and Technology for Semiconductor Materials and Devices   (Sapporo Japan) 

    発表年月: 1993年09月

  • Helium gas mixing in the nitrogen plasma for the control of the acceptor concentration in p-ZnSe

    M. Kobayashi, H. Tosaka, T, Nagatake T, Yoshida, A. Yoshikawa

    6th International Conference on II-VI compounds and Related Optoelectronic Materials   (Newport RI) 

    発表年月: 1993年09月

  • Design on Structures of Lattice-matched Zn(Cd)S(Se) Superlattice

    A.W. Jia, M. Kobayashi, A. Yoshikawa

    20th Alloy Semiconductor Physics and Electronics Symposium   (IzuNagaoka Japan) 

    発表年月: 1993年07月

  • MBE Growth of p-type ZnSe Using a Mixture of N2 and He and the Application to Laser Diodes

    H. Tosaka, S, Matsumoto T, Nagatake T, Yoshida M. Kobayashi, A. Yoshikawa

    20th Alloy Semiconductor Physics and Electronics Symposium   (IzuNagaoka Japan) 

    発表年月: 1993年07月

  • In-situ probing of the ZnSe MOMBE growth process by surface photo-interference method

    S. Tokita, M. Kobayashi, A. Yoshikawa

    4th International Conference on Chemical Beam Epitaxy and Related Growth Technique   (Nara Japan) 

    発表年月: 1993年07月

  • Design of Pseudo-Ternary and Quaternary Alloys by Superlattices Consisting of (Zn,Cd)(S,Se) Binary II-VI Compounds

    A.W. Jia, M. Kobayashi, A. Yoshikawa

    35th Electric Materials Conference   (Colorado USA) 

    発表年月: 1993年06月

  • ZnCdSe/ZnSSeレーザ素子の解析

    今宿亙, 高橋政志, 小林正和, 吉川明彦

    第40回応用物理学関係連合講演会   (東京)  応用物理学会  

    発表年月: 1993年03月

     概要を見る

    1a-ZN-7

  • N2とHeの混合ガスを用いたプラズマ励起ドーピングによるp型ZnSeのMBE成長

    登坂裕之, 松本繁之, 長竹剛, 吉田孝, 小林正和, 吉川明彦

    第40回応用物理学関係連合講演会   (東京)  応用物理学会  

    発表年月: 1993年03月

     概要を見る

    31p-ZN-6

  • プラズマ励起窒素を用いたMBE成長ZnSeへのプレーナ・ドーピング

    松本繁之, 登坂裕之, 長竹剛, 吉田孝, 小林正和, 吉川明彦

    第40回応用物理学関係連合講演会   (東京)  応用物理学会  

    発表年月: 1993年03月

     概要を見る

    31a-ZN-7

  • MOVPE法におけるプラズマ励起窒素のZnSeへのドーピング

    徐増儀, 小林正和, 吉川明彦

    第40回応用物理学関係連合講演会   (東京)  応用物理学会  

    発表年月: 1993年03月

     概要を見る

    31a-ZN-6

  • ZnCdSSe系格子整合超格子構造の設計

    賈岸偉, 小林正和, 吉川明彦

    第40回応用物理学関係連合講演会   (東京)  応用物理学会  

    発表年月: 1993年03月

     概要を見る

    30a-ZN-2

  • ZnSeの光MOVPE成長機構の光によるその場観察法を用いた検討

    佐藤浩太郎, 高村義明, 小林正和, 吉川明彦

    第40回応用物理学関係連合講演会   (東京)  応用物理学会  

    発表年月: 1993年03月

     概要を見る

    29p-ZN-8

  • 表面光干渉法によるCdSのALE成長過程のその場観察

    山口俊哉, 田尾中, 秦野孝行, 小林正和, 吉川明彦

    第40回応用物理学関係連合講演会   (東京)  応用物理学会  

    発表年月: 1993年03月

     概要を見る

    29p-ZN-7

  • 表面光干渉法によるZnSeのMOMBE成長過程のその場観察

    時田茂, 宮地護, 小林正和, 吉川明彦

    第40回応用物理学関係連合講演会   (東京)  応用物理学会  

    発表年月: 1993年03月

     概要を見る

    29p-ZN-6

  • DMSe2をSe原料に用いたZnSeのMOVPE成長と評価

    田中丈久, 松井亮, 小林正和, 吉川明彦

    第40回応用物理学関係連合講演会   (大阪)  応用物理学会  

    発表年月: 1993年03月

     概要を見る

    29p-ZN-2

  • p型ZnSe:Nとラジカルドーピング

    吉川明彦, 小林正和

    第53回応用物理学会学術講演会   (大阪)  応用物理学会  

    発表年月: 1992年09月

     概要を見る

    18p-K-8

  • 減圧MOVPEによるCdSの原子層成長

    山口俊哉, 賈岸偉, 小林正和, 吉川明彦

    第53回応用物理学会学術講演会   (大阪)  応用物理学会  

    発表年月: 1992年09月

     概要を見る

    18a-SL-28

  • ZnSeのMOVPE成長におけるRD法によるその場観察

    佐藤浩太郎, 徐増儀, 小林正和, 吉川明彦

    第53回応用物理学会学術講演会   (大阪)  応用物理学会  

    発表年月: 1992年09月

     概要を見る

    18a-SL-23

  • N2Oの光励起による窒素ドープZnCdSeのMBE成長

    松本繁之, 吉田孝, 登坂裕之, 小林正和, 吉川明彦

    第53回応用物理学会学術講演会   (大阪)  応用物理学会  

    発表年月: 1992年09月

     概要を見る

    17a-SL-19

  • N2Oの光励起による窒素ドープZnSeのMBE成長

    登坂裕之, 松本繁之, 吉田孝, 小林正和, 吉川明彦

    第53回応用物理学会学術講演会   (大阪)  応用物理学会  

    発表年月: 1992年09月

     概要を見る

    17a-SL-18

  • ZnCdSSe系格子整合超格子のバンドギャップの解析

    賈岸偉, 山口俊哉, 小林正和, 吉川明彦

    第53回応用物理学会学術講演会   (大阪)  応用物理学会  

    発表年月: 1992年09月

     概要を見る

    16a-SM-14

  • 表面光吸収法によるZnSe成長過程のその場観察

    時田茂, 小林正和, 吉川明彦

    第53回応用物理学会学術講演会   (大阪)  応用物理学会  

    発表年月: 1992年09月

     概要を見る

    16a-SM-9

  • MOMBE of ZnSe Using Cracked Metalorganic-gases with Hydrogen

    S. Matsumoto, M. Kobayashi, A. Yoshikawa

    The 3rd International Conference on High Technology   (Makuhari Chiba) 

    発表年月: 1992年09月

  • Review (present experimental status) and N Doping Using RF Plasma in ZnSe and ZnTe and Blue-Laser

    M. Kobayashi  [招待有り]

    The 5th International Conference on Shallow Impurities in Semiconductors   (kobe Japan) 

    発表年月: 1992年08月

  • Blue and green laser diodes and LEDs in ZnSe-based quantum structures

    A. V. Nurmikko, Robert L. Gunshor, Nobuo Otsuka, M. Kobayashi  [招待有り]

    Conference on Solid State Devices and Materials   (Tsukuba Japan) 

    発表年月: 1992年08月

     概要を見る

    Recent advances in pn-junction quantum well light emitter structures in the blue-green in the authors laboratories are reviewed. The results include relatively efficient (0.1% at T = 300 K) LEDs and injection diode lasers, the latter having reached cw operation at T = 77K and pulsed to room temperature with threshold current density of 1 kA/cm2.

  • Widegap II-VI Blue Laser Diodes

    R. L. Gunshor, M. Kobayashi, A. V. Nurmikko, N. Otsuka  [招待有り]

    The 11th Alloy Semiconductor Physics and Electronics Symposium   (Kyoto Japan) 

    発表年月: 1992年07月

  • Blue and Blue/green Injection Laser Diodes and Light Emitting Diodes

    W. Xie, D.C. Grillo, R.L. Gunshor, M. Kobayashi, N. Otsuka, G.C. Hua, H. Jeon, J. Ding, A.V. Nurmikko

    March Meeting of the American Physical Society   (Indianapolis IN)  応用物理学会  

    発表年月: 1992年03月

  • Growth and Characterization of ZnSe/ZnCdSe Diode Structures on (In,Ga)As Buffer Layers

    G.C. Hua, N. Otsuka, W. Xie, D.C. Grillo, M. Kobayashi, R.L. Gunshor

    Fall Meeting of Materials Research Society   (Boston MA) 

    発表年月: 1991年12月

  • The MBE Growth of Widegap II-VI Injection Lasers and LEDs

    W. Xie, D.C. Grillo, M. Kobayashi, R.L. Gunshor, H. Jeon, J. Ding, A.V. Nurmikko, G.C. Hua, N. Otsuka

    Fall Meeting of Materials Research Society   (Boston MA) 

    発表年月: 1991年12月

  • Blue/Green Injection Lasers and Light Emitting Diodes

    W. Xie, D.C. Grillo, R.L. Gunshor, M. Kobayashi, G.C. Hua, N. Otsuka, H. Jeon, J. Ding, A.V. Nurmikko

    11th Molecular Beam Workshop   (Austin TX) 

    発表年月: 1991年09月

  • ZnSe/Zn0.8Cd0.2Se Quantum Well LEDs and Lasers

    W. Xie, D.C. Grillo, M. Kobayashi, R.L. Gunshor, G.C. Hua, N. Otsuka, H. Jeon, J. Ding, A.V. Nurmikko

    5th International Conference on II-VI Compounds   (Okayama Japan) 

    発表年月: 1991年09月

  • Optical Properties and Device Prospects of ZnSe-based Quantum Structures

    A.V. Nurmikko, R.L. Gunshor, M. Kobayashi  [招待有り]

    5th International Conference on II-VI Compounds   (Okayama Japan) 

    発表年月: 1991年09月

  • II-VI/III-V Interface Formation

    R.L. Gunshor, M. Kobayashi, N. Otsuka  [招待有り]

    7th International Conference on Vapor Growth and Epitaxy   (Nagoya Japan) 

    発表年月: 1991年07月

  • III-VI Interfacial Compounds

    M. Kobayashi, D.R. Menke, R.L. Gunshor

    IEEE/LEOS Summer Topical Meeting on Epitaxial Materials and In-situ Processing for Optoelectronic Devices   (Newport CA) 

    発表年月: 1991年07月

  • Interface Properties of II-VI/III-V Heterostructures

    R.L. Gunshor, M. Kobayashi, N. Otsuka  [招待有り]

    Materials Research Society Meeting Symposium C   (Anaheim CA) 

    発表年月: 1991年03月

  • Vacancy Ordering at the Ga2Se3/GaAs Epitaxial Interface

    D. Li, Y. Nakamura, N. Otsuka, J, Qiu, M. Kobayashi, R.L. Gunshor

    1991 March Meeting of the American Physical Society   (Cincinnati OH) 

    発表年月: 1991年03月

  • Interface Properties of InSb Based Heterovalent Multilayer Structures

    D.R. Menke, J, Han T, Stavrinides R.L. Gunshor, M. Kobayashi, Y. Nakamura, N. Otsuka

    1991 March Meeting of the American Physical Society   (Cincinnati OH) 

    発表年月: 1991年03月

  • Reconstruction at the Ga2Se3/GaAs Epitaxial Interface

    D. Li, Y. Nakamura, N. Otsuka, J, Qiu, M. Kobayashi, R.L. Gunshor

    18th Anual Conference on Physics & Chemistry of Semiconductor Interfaces   (Long Beach CA) 

    発表年月: 1991年01月

  • An XPS Study of Bonding at ZnSe/GaAs Heterovalent Interfaces

    D.R. Menke, J, Qiu, R.L. Gunshor, M. Kobayashi, D. Li, Y. Nakamura, N. Otsuka

    18th Anual Conference on Physics & Chemistry of Semiconductor Interfaces   (Long Beach CA) 

    発表年月: 1991年01月

  • Structural Properties of InSb/CdTe Heterovalent Multilayer Structures

    J.L. Glenn Jr, S. O M. Kobayashi, R.L. Gunshor, L.A. Kolodziejski D. Li, N. Otsuka

    the Materials Research Society Fall Meeting   (Boston MA) 

    発表年月: 1990年11月

  • High-Resolution Magnetooptics and Excitation Spectroscopy of Ultra-Pure MBE-Grown ZnSe/GaAs Epilayers

    G. Kudlek, J, G?towski, S. Durbin, D. Menke, M. Kobayashi, R.L. Gunshor

    20th Int'l Conference on the Physics of Semiconductors   (Thessaloniki GREECE) 

    発表年月: 1990年08月

  • Hot Luminescence and Exciton in ZnTe Quantum Wells: Effects of Dimensionality and Finite Disorder

    N. Pelekanos, Q. Fu, J. Ding, A.V. Nurmikko, M. Kobayashi, S. Durbin, J. Han, R.L. Gunshor

    20th Int'l Conference on the Physics of Semiconductors   (Thessaloniki GREECE) 

    発表年月: 1990年08月

  • Formation of Heterojunction Band Offsets: Isoelectronic Viewpoint in ZnSe:Te Quantum Wells

    J. Ding, Q. Fu, N, Pelekanos W. Watecki, A.V. Nurmikko, S. Durbin J, Han, M. Kobayashi, R.L. Gunshor

    20th Int'l Conference on the Physics of Semiconductors   (Thessaloniki GREECE) 

    発表年月: 1990年08月

  • Strong Electronic Confinement in CdTe Single Quantum Wells; Excitonic Emission from Infrared to Blue

    J. Ding, N. Pelekanos, Q. Fu, W. Walecki, A.V. Nurmikko J. Han, S. Durbin, M. Kobayashi, R.L. Gunshor

    20th Int'l Conference on the Physics of Semiconductors   (Thessaloniki GREECE) 

    発表年月: 1990年08月

  • Reconstruction Structure at Ga2Se3/GaAs Epitaxial Interface

    D. Li, Y. Nakamura, N. Otsuka, J, Qiu, M. Kobayashi, R.L. Gunshor

    6th Int'l. Conference on MBE   (San Diego CA) 

    発表年月: 1990年08月

  • . Quantum Wells with Zincblende MnTe Barriers

    J. Han, S.M. Durbin, R.L. Gunshor, M. Kobayashi, D.R. Menke, Q. Fu, N. Pelekanos, A.V. Nurmikko, Y. Nakamura, N. Otsuka

    6th Int'l. Conference on MBE   (San Diego CA) 

    発表年月: 1990年08月

  • ZnSe/GaAs Heterovalent Interfaces: Interface Microstructure vs Electrical Properties

    J. Qiu, M. Kobayashi, R.L. Gunshor, Q.-D. Qian, D.R. Menke, D. Li, N. Otsuka

    6th Int'l. Conference on MBE   (San Diego CA) 

    発表年月: 1990年08月

  • Blue Luminescence from CdTe/MnTe Single Quantum Wells

    S.M. Durbin, J, Han, M. Kobayashi, R.L. Gunshor, D.R. Menke, Q. Fu, N. Pelekanos, A.V. Nurmikko

    Electronic Materials Conference   (Santa Barbara CA) 

    発表年月: 1990年06月

  • Growth and Characterization of pseudomorphic ZnTe/AlSb/GaSb Heterostructures

    D.L. Mathine, J, Han, M. Kobayashi, R.L. Gunshor, D.R. Menke, M. Vaziri, J. Gonsalves, N. Otsuka, Q. Fu, M. Hagerott, A.V. Nurmikko

    1990 March Meeting of the American Physical Society   (Anaheim CA) 

    発表年月: 1990年03月

  • Hot Luminescence in ZnTe/MnTe Single Quantum Wells: The Role of Excitons and Disorder

    N. Pelekanos, Q. Fu, J. Ding, A.V. Nurmikko, S. Durbin, M. Kobayashi, R.L. Gunshor

    1990 March Meeting of the American Physical Society   (Anaheim CA) 

    発表年月: 1990年03月

  • . Kinetics of Exciton Capture at Tellurium Isoelectronic Centers in Delta-doped ZnSe Quantum Wells

    D. Lee, Q. Fu, A.V. Nurmikko, R.L. Gunshor, M. Kobayashi

    1990 March Meeting of the American Physical Society   (Anaheim CA) 

    発表年月: 1990年03月

  • Far Infrared Magnetooptical Study of MBE-grown CdTe/InSb/CdTe Single Quantum Well

    G.L. Yang, T. Wojtowicz, M. Dobrowolska, J.K. Furdyna, J. Glenn, M. Kobayashi, L.A. Kolodziejski, R.L. Gunshor

    1990 March Meeting of the American Physical Society   (Anaheim CA) 

    発表年月: 1990年03月

  • Atomic Structure of the ZnSe/GaAs Heteroepitaxial Interface

    D. Li, N. Otsuka, Y. Nakamura, J. Qiu, M. Kobayashi, R.L. Gunshor

    1990 March Meeting of the American Physical Society   (Anaheim CA) 

    発表年月: 1990年03月

  • Electrical Properties of ZnSe/GaAs Heterointerfaces

    R.L. Gunshor, M. Kobayashi, L.A. Kolodziejski N. Otsuka, Q.-D. Qian  [招待有り]

    1990 March Meeting of the American Physical Society   (Anaheim CA) 

    発表年月: 1990年03月

  • Radiative Recombination in CdTe/MnTe Quantum Wells; Emission from Near Infrared to Blue Wavelengths

    Q. Fu N. Pelekanos, J. Ding, A.V. Nurmikko, S. Durbin J, Han, M. Kobayashi, R.L. Gunshor

    International Quantum Electronics Conference  

    発表年月: 1990年

  • . Influence of GaAs Surface Stoichiometry on the Electrical Properties of As-grown Epitaxial ZnSe/epitaxial GaAs Heterointerfaces

    J. Qiu, Q.D. Qian, R.L. Gunshor, M. Kobayashi, D.R. Menke, D. Li, N. Otsuka

    the 17th Annual Conference on Physics and Chemistry of Semiconductor Interfaces   (Clearwater Beach FL) 

    発表年月: 1990年01月

  • Transmission Electron Microscopy of II-VI/III-V Semiconductor Interfaces

    D. Li, N, Otsuka M, Kobayashi, R.L. Gunshor, L.A. Kolodziejski

    the Materials Research Society Fall Meeting   (Boston MA) 

    発表年月: 1989年11月

  • Effect of GaAs Surface Stoichiometry on the Interface of As-grown Epitaxial ZnSe/Epitaxial GaAs Heterostructures

    J. Qiu, Q.-D. Qian, M. Kobayashi, R.L. Gunshor, D.R. Menke, D. Li, N. Otsuka

    the Materials Research Society Fall Meeting   (Boston MA) 

    発表年月: 1989年11月

  • Pseudomorphic ZnTe/AlSb/GaSb Heterostructures by Molecular Beam Epitaxy

    D.L. Mathine, J, Han, M. Kobayashi, R.L. Gunshor, D.R. Menke, M. Vaziri, J. Gonsalves, N. Otsuka, Q. Fu, M. Hagerott, A.V. Nurmikko

    the Materials Research Society Fall Meeting   (Boston MA) 

    発表年月: 1989年11月

  • Recent Advances in Strained Wide-Gap II-VI Semiconductor Superlattices

     [招待有り]

    MRS Fall Meeting '89 Symposium E "Properties of II-VI Semiconductors: Bulk Crystals Epitaxial Films Quantum Well Systems and Dilute Magnetic Systems"   (Boston MA) 

    発表年月: 1989年11月

  • Pseudomorphic ZnTe/AlSb/GaSb for Widegap Light Emitters

    D.L. Mathine, S.M. Durbin, M.Kobayashi, R.L. Gunshor, D.R. Menke, J. Gonsalves, N. Otsuka, Q. Fu, M. Hagerott, A.V. Nurmikko

    Molecular Beam Epitaxy Workshop   (Raleigh NC) 

    発表年月: 1989年09月

  • Molecular Beam Epitaxy of Pseudomorphic ZnSe/Epitaxial GaAs with Low Interface State Density

    Q.-D. Qian, J. Qiu, M. Kobayashi, R.L. Gunshor, L.A. Kolodziejski, M.R. Melloch, J.A. Cooper, Jr, J.M. Gonsalves, N. Otsuka

    16th International Symposium on GaAs and Related Compounds   (Karuizawa Japan) 

    発表年月: 1989年09月

  • Strong Confinement Effects in CdTe/MnTe Quantum Wells: A New Strained Layer Binary II-VI Heterostructure

    Q. Fu N. Pelekanos, A.V. Nurmikko, S. Durbin, J, Han Sungki, O, D. Menke, M. Kobayashi, R.L. Gunshor

    EP2DS   (Grenoble France) 

    発表年月: 1989年09月

  • Optical Spectroscopy of ZnTe/MnTe Quantum Well Structures

    N. Pelekanos, Q. Fu, S. Durbin, M. Kobayashi R. Gunshor, A.V. Nurmikko

    Fourth International Conference on II-VI Compounds   (Berlin Germany) 

    発表年月: 1989年09月

  • High-Density Luminescence and Excitation Spectroscopy of MBE Grown ZnSe/GaAs Epilayers

    G. Kudlek N, Presser J. G?towski, S.M. Durbin, D. Menke, M. Kobayashi, R.L. Gunshor

    Fourth International Conference on II-VI Compounds   (Berlin Germany) 

    発表年月: 1989年09月

  • Widegap II-VI Heterostructures

    R.L. Gunshor, M. Kobayashi, L.A. Kolodziejski, A.V. Nurmikko  [招待有り]

    Fourth International Conference on II-VI Compounds   (Berlin Germany) 

    発表年月: 1989年09月

  • MBE of Wide Bandgap II-VI Compounds

    R.L. Gunshor, M. Kobayashi, L.A. Kolodziejski, A.V. Nurmikko, N. Otsuka  [招待有り]

    9th International Conference on Crystal Growth (ICCG-9)   (Sendai Japan) 

    発表年月: 1989年08月

  • ZnTe/MnTe: A New Metastable Wide Gap II-VI Heterostructure

    S.M. Durbin, M. Kobayashi, Q. Fu, N. Pelekanos, R.L. Gunshor, A.V. Nurmikko

    Fourth International Conference on Modulated Semiconductor Structures   (Ann Arbor MI) 

    発表年月: 1989年07月

  • Molecular Beam Epitaxy of Pseudomorphic ZnTe/AlSb/GaSb

    D.L. Mathine, S.M. Durbin, R.L. Gunshor, M. Kobayashi, D.R. Menke, J. Gonsalves, N. Otsuka, Q. Fu, M. Hagerott, A.V. Nurmikko

    Fourth International Conference on Modulated Semiconductor Structures   (Ann Arbor MI) 

    発表年月: 1989年07月

  • Transmission Electron Microscope Study of II-VI/III-V Semiconductor Interfaces

    N. Otsuka, D. Li, J.M. Gonsalves, C. Choi, M. Kobayashi, L.A. Kolodziejski, R.L. Gunshor  [招待有り]

    Fourth International Conference on Modulated Semiconductor Structures   (Ann Arbor MI) 

    発表年月: 1989年07月

  • Pseudomorphic ZnTe/AlSb/GaSb Heterostructures Grown by Molecular Beam Epitaxy

    D.L. Mathine, S.M. Durbin, M. Kobayashi, R.L. Gunshor, D.R. Menke, J. Gonsalves, N. Otsuka, Y.R. Lee, A.K. Ramdas, Q. Fu, M. Hagerott, A.V. Nurmikko

    1989 Electron Materials Conference   (Urbana-Champaign IL) 

    発表年月: 1989年06月

  • MBE of Wide Bandgap II-VI Compounds

    R.L. Gunshor, M. Kobayashi, L.A. Kolodziejski, A.V. Nurmikko, N. Otsuka  [招待有り]

    American Vacuum Society 4th Annual Illinois Chapter Spring Meeting   (Urbana-Champaign IL) 

    発表年月: 1989年04月

  • Low Interface State Density at a Pseudomorphic ZnSe/epitaxial GaAs Interface

    Q.-D. Qian, J. Qiu, M. Kobayashi, R.L. Gunshor, L.A. Kolodziejski, M.R. Melloch, J.A. Cooper, Jr, J.M. Gonsalves, N. Otsuka

    MRS Meeting Spring   (San Diego CA) 

    発表年月: 1989年04月

  • Wide Gap II-VI DMS Superlattices: MBE Growth and Characterization

    R.L. Gunshor, L.A. Kolodziejski M. Kobayashi, A.V. Nurmikko, N. Otsuka  [招待有り]

    MRS Meeting Spring   (San Diego CA) 

    発表年月: 1989年04月

  • Molecular Beam Epitaxy of InSb/CdTe Multilayered Structures

    M. Kobayashi, J.L. Glenn Sungki, O, R.L. Gunshor, L.A. Kolodziejski D. Li, N. Otsuka, M. Hagerott, T. Heyen, A.V. Nurmikko

    1989 March Meeting of the American Physical Society   (St. Louis MO) 

    発表年月: 1989年03月

  • Low Interface State Density at an MBE Grown Pseudomorphic ZnSe/Epitaxial GaAs Interface

    Q.-D. Qian, J. Qiu, M. Kobayashi, R.L. Gunshor, L.A. Kolodziejski M, R. Melloch, J. A. Cooper, Jr. J, M. Gonsalves, N. Otsuka

    1989 March Meeting of American Physical Society   (St. Louis MO) 

    発表年月: 1989年03月

  • Electrical Characterization of an Epitaxial ZnSe/epitaxial GaAs Heterointerface

    Q.-D. Qian, J. Qiu, M. Kobayashi, R.L. Gunshor, M.R. Melloch, J.A. Cooper

    16th Physics and Chemistry of Semiconductor Interface Conference   (Bozeman MO) 

    発表年月: 1989年02月

  • II-VI/III-V Heterostructures: Epilayer-on-epilayer Structures

    R.L. Gunshor, L.A. Kolodziejski M. Kobayashi N. Otsuka, A.V. Nurmikko  [招待有り]

    SPIE-The International Society for Optical Engineering   (Santa Clara CA) 

    発表年月: 1988年11月

  • Electron Microscope Study of Initial Stage of Growth of ZnSe on GaAs

    J.M. Gonsalves, N. Otsuka, J, Qiu M. Kobayashi, R.L. Gunshor, L.A. Kolodziejski

    Materials Research Society Meeting   (Boston MA) 

    発表年月: 1988年11月

  • II-VI/III-V Heterointerfaces: Epilayer of Epilayer Structures

    R.L. Gunshor, L.A. Kolodziejski, N. Otsuka, A.V. Nurmikko, M. Kobayashi, M.R. Melloch  [招待有り]

    Electrochemical Society Fall Meeting   (Chicago IL) 

    発表年月: 1988年10月

  • Molecular Beam Epitaxy of InSb/CdTe Heterostructures

    J.L. Glenn, Jr. Sungki, O, L.A. Kolodziejski, R.L. Gunshor, M. Kobayashi

    Molecular Beam Epitaxy Workshop   (West Lafayette IN) 

    発表年月: 1988年09月

  • Low Interface State Density at the Molecular Beam Epitaxialy Grown Thermally Annealed ZnSe/GaAs Interface

    Q.-D. Qian, J. Qiu, M.R. Melloch, J.A. Cooper, Jr, R.L. Gunshor, L.A. Kolodziejski M. Kobayashi

    15th International Symposium on Gallium Arsenide and Related Compounds   (Altanta GA) 

    発表年月: 1988年09月

  • Passivation of Epitaxial GaAs with Epitaxial ZnSe

    Q.-D. Qian, J. Qiu, G.D. Studtmann, R.L. Gunshor, L.A. Kolodziejski, M.R. Melloch, J.A. Cooper Jr, M. Kobayashi

    5th International Conference on Molecular Beam Epitaxy   (Sapporo) 

    発表年月: 1988年08月

  • Molecular Beam Epitaxy of InSb/CdTe Heterostructures

    J.L. Glenn, Jr.. Sungki, O, L.A. Kolodziejski, R.L. Gunshor, M. Kobayashi, J.M. Gonsalves, N. Otsuka, M. Hagerott, T. Heyen, A.V. Nurmikko  [招待有り]

    5th International Conference on Molecular Beam Epitaxy   (Sapporo) 

    発表年月: 1988年08月

  • ZnSe-ZnTe歪超格子の評価(V)

    道正志郎, 小林正和, 今井彰, 小長井誠, 高橋清

    応用物理学会秋季大会   応用物理学会  

    発表年月: 1987年10月

  • MBE法によりGaAs基板上に作製したZnSe-ZnTe歪超格子の断面観察

    小長井誠, 高橋清, 小林正和, 浦部和順

    日本窯業協会写真展   日本窯業協会  

    発表年月: 1987年10月

  • ZnSe-ZnTe Strained-layer Superlattices: Novel Material for the Future Optoelectronic Devices

    M. Konagai, M. Kobayashi, R. Kimura, K. Takahashi

    The Third International Conference on II-VI compounds   (Montrey CA) 

    発表年月: 1987年07月

  • Electrical Properties of ZnSe-ZnTe Strained-layer Superlattices

    M. Kobayashi, S. Dosho, A. Imai, M. Konagai, K. Takahashi  [招待有り]

    The Third International Conference on Superlattice Microstructures and Microdevices   (Chicago IL) 

    発表年月: 1987年07月

  • Doping Characteristics of ZnSe-ZnTe Strained-layer Superlattice Grown by Molecular Beam Epitaxy

    R. Kimura, S. Dosho, A. Imai, M. Kobayashi, M. Konagai, K. Takahashi

    SPIE's International Conference on Advances in Semiconductors and Semiconductor Structures   (Bay Point FL) 

    発表年月: 1987年03月

  • ZnSe-ZnTe歪超格子の評価(IV)

    今井彰, 小林正和, 木村龍平, 道正志郎, 小長井誠, 高橋清

    応用物理学会春季大会   応用物理学会  

    発表年月: 1987年03月

  • ZnSe-ZnTe歪超格子の断面観察

    小長井誠, 高橋清, 小林正和, 浦部和順

    日本窯業協会写真展   日本窯業協会  

    発表年月: 1986年10月

  • ZnSe-ZnTe歪超格子の評価(III) -界面急峻性の評価-

    小林正和, 木村龍平, 小長井誠, 高橋清

    応用物理学会秋季大会   応用物理学会  

    発表年月: 1986年09月

  • Growth and Characterization of ZnSe-ZnTe Strained-layer Superlattices

    M. Kobayashi, R. Kimura, M. Konagai, K. Takahashi

    The Fourth International Conference on Molecular Beam epitaxy (York  

    発表年月: 1986年09月

  • ZnSe-ZnTe歪超格子の評価(II)

    木村龍平, 三野直樹, 片桐裕則, 小林正和, 小長井誠, 高橋清

    応用物理学会春季大会   (千葉)  応用物理学会  

    発表年月: 1986年04月

  • ZnSe-ZnTe歪超格子の評価(I)

    小林正和, 三野直樹, 片桐裕則, 小長井誠, 高橋清, 浦部和順

    応用物理学会春季大会   (千葉)  応用物理学会  

    発表年月: 1986年04月

  • MBE法により作製したZnSe-ZnTe/InP歪超格子の構造評価

    片桐裕則, 小林正和, 三野直樹, 小長井誠, 高橋清, 浦部和順

    電子通信学会総合全国大会   (新潟)  電子通信学会  

    発表年月: 1986年03月

  • MBE法によるZnSe-ZnTe/InP歪超格子

    小林正和, 三野直樹, 片桐裕則, 木村龍平, 小長井誠, 高橋清

    応用物理学会秋季大会   (京都)  応用物理学会  

    発表年月: 1985年10月

  • ZnSe-ZnTe Strained-layer Superlattice on InP Substrate by Molecular Beam Epitaxy

    M. Kobayashi, N. Mino, M. Konagai, K. Takahashi

    発表年月: 1985年06月

  • プラズマMOCVD法によるZnSe膜の形成

    三野直樹, 小林正和, 小長井誠, 高橋清

    応用物理学会春季大会   (東京)  応用物理学会  

    発表年月: 1985年03月

  • MBE法によるSi基板上へのZnSeの成長と評価

    小林正和, 三野直樹, 小長井誠, 高橋清

    応用物理学会秋季大会   (岡山)  応用物理学会  

    発表年月: 1984年10月

  • ZnSe:Mn薄膜直流EL素子におけるZnSe:Inバッファ層の効果

    小林正和, 三野直樹, 犬塚肇, 小長井誠, 高橋清

    応用物理学会春季大会   (東京)  応用物理学会  

    発表年月: 1984年03月

▼全件表示

特定課題研究

  • m面サファイア基板の高温熱処理とナノファセット形成技術の改善

    2021年  

     概要を見る

    m-面サファイア基板を大気中1500度程度の温度で長時間熱処理を行うと表面の平坦化が進むと同時に特定の2つの面方位が数十ナノメータの間隔で周期的に組み合わさったナノファセット構造が現れることが確認されてきた。どのような温度でどのような時間加熱するとナノファセット構造の状態がどのように変化するかはまだ詳細には確認されていなかったため、ナノファセットを基板として用いた場合に最適な構造がどのようなものであるかは明確に検討されてこなかった。 そこで今期間において、数種類の熱処理条件を実際に試み、どのようなナノファセット構造が得られるのか、どのような状態にすると基板としての特徴を示すことが可能になるのかについて検討を行った。そして、1600度30時間程度の熱処理によってナノファセット構造が明瞭に出現することが確認され、基板として用いることで高品質ZnTe薄膜の作製が可能なことを示した

  • サファイア基板上のZnTe成長初期過程の評価

    2020年  

     概要を見る

    テラヘルツ波検出のためZnTeに注目しておりr面とS面が周期的かつ連続的に並ぶナノファセット構造を持つサファイア基板上ZnTe薄膜の作製を行っている。単一ドメインZnTe薄膜成長のためにナノファセットS面上にZnTe成長核の選択形成を行う必要がある。しかし17.66°の傾斜角をS面方向へつけることによりS面の表面積が小さくなるためZnTe成長核の選択形成は困難であった。SEM解析の結果,RHEEDによるその場観察を行いrナノファセット面からの脱離を確認した後にZn照射を始めることによって多くのZnTeバッファ層をSナノファセット面上に残すことができ,それによりZnTe成長核のS面選択形成が可能となることが明らかとなった

  • 熱処理によるサファイア基板表面形状の制御と薄膜成長に与える影響の評価

    2019年  

     概要を見る

    m面サファイア基板上に分子線エピタキシー法で高品質ZnTe薄膜の作製に取り組んできた。1200~1500℃の高温で基板を大気中に放置することでナノファセットと呼ばれるr面とS面の周期構造が形成可能なことが明らかになった。r面とS面で核形成から成長初期の状態までの間が大きく異なること、特に成長温度によって大きな影響を受けることを明らかにした。特に温度が高くなるにつれてr面上に堆積が減少してくることを明らかにした。さらに成長初期に高温で原料の交互供給をすることが高品質の薄膜作製に重要なことであると明らかにした。実際に成長初期核をS面上に選択的に形成することが可能になったことで極めて配向性の高いZnTe薄膜が得られた。

  • 濡れ性制御近接昇華法によるカルコゲン化合物微細構造作製と太陽電池構造への応用

    2018年  

     概要を見る

    近接昇華法を用いてMo/quartz基板上にソース温度を変化させてCu2Te膜と二段階目のCuGaTe2膜の作製を行い、それぞれの膜厚に与える影響を探査した。また、1段階目のCu2Te中間層の膜厚を一定とし、2段階目のCu2TeとGa2Te3の混合粉末原料の重量を変化させることでCu-Ga-Te膜の形成相にどのような影響を与えるか探査した。ソース温度を上げて作製することにより、太陽電池応用に向けて必要な膜厚1μmのCuGaTe2の作製に成功した。また、二段階目のCu2TeとGa2Te3の混合粉末原料の重量を変化させることで堆積物のGa2Te3のモル分率が変化し、Cu-Ga-Te膜の形成相の種類や量が変化することが明らかとなった。

  • 二段階近接昇華法による高品質カルコパイライト薄膜の光学的特性解析

    2017年  

     概要を見る

    2段階近接昇華法を用いることで高品質テルル系カルコパイライト薄膜の作製が可能になってきた。様々な条件によってシリコン基板上に作製されたAgGaTe2の光学的特性を極低温フォトルミネッセンス(PL)法によって評価した。PLスペクトルから1.02 eV付近と1.32 eV付近に2つのピークが観測された。詳細解析の結果1.32 eV付近の発光は自由励起子由来の発光であった。状態図をもとに薄膜内の結晶について検討を行ったところ、AgGa5Te8を含むAgGaTe2薄膜においては自由励起子由来の発光がつよく確認されるがAg2Teを含むと自由励起子由来の発光が消光することが明らかになった。

  • 2段階近接昇華法による高品質カルコパイライト薄膜の作製と多接合型太陽電池構造応用

    2017年  

     概要を見る

    2段階近接昇華法を用いることで高品質テルル系カルコパイライト薄膜の作製が可能になってきた。AgGaTe2の成果をもとに、CuGaTe2の2段階近接昇華法が応用可能かどうかについて検討を行った。そこで中間層材料としてCu2Teに着目した。シリコン基板上にCu2Te中間層を作製したところ、面内密度の改善が進み、比較的高密でのCu2Te粒状構造が確認された。さらにMo上にCu2Teを作製したところ、ほぼ膜状に分布した構造も作製できることが明らかになった。さらにその上にCuGaTe2を作製したところ、平坦性の高い薄膜状の結晶が得られるようになった。X線回折法を用いて結晶性を評価したところ、CuGaTe2が得られていることが明らかになった。

  • テルル系カルコパイライト薄膜の開発と高効率太陽電池応用

    2016年  

     概要を見る

    Te系I-III-VI2族カルコパイライト材料のなかでもAgGaTe2は室温でのバンドギャップが1.3eVと太陽電池応用に適している。しかし、ソースにAg2TeとGa2Te3の混合粉末を用いて、Ag2Te中間層上に堆積させているため、ストイキオメトリ制御が難しく、Ag2TeやAgGa5Te8といった副生成物が生成されやすい。そこで本研究ではそれぞれの膜厚をコントロールすることで組成制御が比較的容易に行えるGa2Te3/Ag2Teという2層構造に着目し、AgGaTe2薄膜の形成をGa2Te3/Ag2Teを連続して堆積させることにより試みた。Ag2Te層上にGa2Te3層を堆積させた膜は、AgGaTe2由来のピークのみが表れた。このことよりGa2Te3堆積中にGa2Te3の堆積とGa2Te3/Ag2Te層の再結晶化が同時に起こり、結果としてAgGaTe2膜が形成されていることが明らかとなった。

  • 界面制御による異種結晶構造積層の高品質化

    2015年  

     概要を見る

    電気光学効果を利用した高感度テラヘルツ波検知器の実現に向け、透明基板であるサファイア上に面方位が制御された状態の高品質ZnTe薄膜を作製することを目指している。サファイアS面やR面を基板にもちい、成長薄膜との界面の方位関係を調べた。S面上に作製されたZnTeをX線回折法、特に極点図法を用いて解析した。S面基板上に作製する場合にはサファイアC面が大きな影響を与えているが、R面上には異なった形で結晶成長が行われた。ただし、結晶性に関してはS面上に作製されたZnTeより高品質であることが明らかになった。界面を詳細に検討し、C面の情報を引継ぐと同時に表面の原子配置も大きな影響を及ぼしていることが明らかになった。

  • 高分散BaZnS:Mnナノ粒子による透明インキ作製と高性能薄膜の開発

    2013年  

     概要を見る

    再生可能なエネルギー源に関する研究開発が現在盛んに行われている。中でも太陽電池に関する研究は実用化に近付いており、社会においてニーズの高い重要な研究テーマである。太陽電池デバイスの中でも単結晶Si太陽電池は、他の太陽電池に比べて寿命が長く太陽光の変換効率が高い。しかし、Si太陽電池の変換効率は約20%で理論限界値に近づいている。シリコン太陽電池の課題の一つに太陽光の高エネルギー成分である短波長成分を有効活用出来ていないことが挙げられる。本研究では、この短波長成分を蛍光体の利用により長波長光へ変換し太陽光エネルギーの利用効率を改善することについて注目した。特に波長変換材料には、蛍光効率の高い赤色蛍光体Ba2ZnS3:Mn (BZS)に注目した。この赤色蛍光体BZSをナノ粒子にし単結晶Si太陽電池の前面に配置することで、太陽光の長波長光を損失無くそのまま透過させ短波長光だけを変換することが期待出来る。従来の研究では、BZSを物理的粉砕法によりナノ粒子にし、スピンコート法を用いることで赤色蛍光ナノ粒子塗布膜を作製してきた。しかしこの赤色蛍光ナノ粒子塗布膜は、粉砕されたままのBZSナノ粒子の発光強度が劣化していることが原因で光学的特性が十分なものとは考えにくかった。そこで粉砕されたままのBZSナノ粒子の発光強度回復について検討を行った。粉砕によるダメージは真空中のアニール処理により回復させることに注目した。 アニール温度を1100℃まで上げるにつれ試料のX線回折信号測定の信号強度が強くなっていることから、BZSの結晶性が回復していることが確認出来た。また、1000,1100℃でアニール処理したBZSは従来のアニール処理のBZSと比較すると、131の回折強度が2.5倍になった。このことからBZSの結晶性が従来よりも良くなっていることが明らかになった。今回用いたアニール条件の範囲ではアニールを行ってもスペクトル形状への影響は確認されなかった。PLスペクトルのピーク値は630nmであり、半値幅は全て同じであった。また、従来のZnSを隣接しないアニール処理を施したBZSと比較して、蛍光強度が約8倍になった。アニール温度を1000℃まで上昇させると、それに伴ってPL強度は単調に増加した。そして1000℃以上ではでPL 強度の変化は、ほとんど無くなっていることも明らかになった。アニール温度が高温になるに従い、強い蛍光が観測されたのは高温のアニール処理により粒子表面に存在していた欠陥が回復されたためであると考えられる。

  • 紫外線A領域直測センサ用ZnMgCdS系混晶材料の創製

    2004年  

     概要を見る

    GaAsに格子整合し、かつ室温でのEgを3eVに制御可能なZnMgCdS系材料に注目し、紫外線センサへの適応性を検討した。4元混晶に限定することなく、センサ特性改善のため超格子構造のZn0.6Cd0.4S/Mg0.8Cd0.2Sを作製し、紫外線センサへの適応性の検討を行なったところZnMgCdS材料の場合と同様に紫外光のみ選択的に感度のあるセンサを作製することができた。しかし、結晶成長とともに3次元成長が起こり結晶性が悪化し、センサ特性に影響が出るという問題が明らかになった。そこで、従来とはことなり、GaAs基板上に作製する代わりにエピタキシャル成長させた平坦なGaAs上にZnCdS/MgCdSを作製し、結晶性の改善とセンサの分光感度特性の改善を試みた。(100)GaAsエピタキシャル膜上にZnSeバッファ層成長後、ZnMgS/CdMgSをZn、Mg及びCdS化合物を用いて成長させた。組成はZn 0.4Cd 0.6S/Mg 0.8Cd 0.2S付近に設定し、層厚は9 &#8211;60Å/8 &#8211;20Åで作製した。RHEED観察においてGaAs基板上にZnSeバッファ層を成長した場合は成長開始直後からスポットになった。それに対しGaAsエピタキシャル膜上の場合は成長開始直後からストリークが見られ、超格子600nm成長後でもGaAsエピタキシャル膜上に成長したものはストリークが保たれていた。これらのことはGaAsとの界面の平坦性が改善されたことにより超格子の結晶性を改善できたためと考えられる。PL・反射スペクトルから2.95eV付近にEgに対応した強い発光が得られた。本超格子を用いて光導電素子のUVAセンサを作製したところ、従来の構造に比べカットオフ波長付近での感度特性が改善された。

  • ワイドギャップ材料基板上ZnMgCdS系紫外線A直測センサの作成に関する基礎研究

    2002年  

     概要を見る

    近年紫外線に関する諸問題が注目されており,紫外線センサの研究が活発に進められている.GaN系材料ではUVAを感知することは困難なため,Ⅱ-Ⅵ族の4元混晶が注目されている.ZnMgCdSは(100)GaAs基板に格子整合し,かつUVAのエネルギーに対応する3eVをMg濃度10%で実現できる.また,Ⅱ-Ⅱ-Ⅱ-Ⅵ系の材料であることから組成制御もしやすいと考えられる.そこで,ZnMgCdSをMBEにより成長し,UVAセンサとしての適応性について検討した. ZnMgCdSをZn,Mg及びCdS化合物を用いて(100)GaAs基板上に成長させた.条件は基板温度150-230℃,BEP比(Zn+Mg)/CdS=0.03-0.35の間で変化させた.基板温度150℃でBEP比=0.03の場合,CdがZn,Mgに置換されなかった.次に220℃,BEP比=0.068ではCdがZnとMgに対して1:1の割合で置換されていた.その結果,GaAsにほぼ格子整合し,室温でのバンド端が3eV付近のZnMgCdSを成長させることができた.さらに,230℃でBEP比=0.35に上げるとCdがほぼ100%置換されていた.これらのことは従来報告されているZnCdSのSの被服率によるZn,Cd付着率の関係と一致していた.10KでのPLスペクトル測定の結果より、Zn,Mgの含有量が増えるに従ってエネルギーギャップが増大していることが明らかになった.但し組成比が面内で分布しているためかピークは比較的ブロードなものになった.また,Au電極を蒸着することによりMSM構造のセンサを作製した.その結果,UVA以上のエネルギーをもつ光にのみ選択的に反応し,伝導率が変化していることが明らかになった。

  • クエン酸系試薬によるZnTe表面の改質と高性能純緑色発光素子開発への適応

    2000年  

     概要を見る

     ワイドギャップII-VI族化合物半導体は禁制帯幅が広いことから可視光領域の発光・受光素子用材料として注目されている。特に近年はその量子ドット構造に関しては特徴的な発光特性が期待できることより注目されている。量子ドットを電子素子として作りこむことを想定するとエピタキシャル膜中に量子ドットを作りこむことが課題となってくる。我々は特に基板の中でも、結晶性がよく、広く普及されつつあるZnTe基板に注目し、その基板上に量子ドットを形成することを意図した。 基板が普及しつつあるとはいうものの、まだ、エピタキシャル成長用の基板表面処理技術が確立していないことは、量子ドットの成長に対して大きな問題点となっている。そこで、さまざまな化学エッチャントにより基板表面を処理し、エッチングの表面平坦性・表面ストイキオメトリ・表面酸化膜(保護膜)の厚みなどについて検討を行った。 基板の化学処理方法としては、通常の化合物半導体で広く使われている硫酸系の試薬、HBr系試薬、クエン酸系試薬などを用いた。まず、表面平坦性の観点では硫酸系の試薬を使った場合には鏡面が得られなくなるほど悪化してしまうため、適当でないとの結論に達した。その他の試薬では、薬品濃度が表面平坦性の再現性に影響を与えるが、条件を十分に設定することにより、エピタキシャル膜の成長に利用できる程度の表面平坦性が得られることがAFM観察より明らかになった。また、HBr系の試薬を用いた場合は表面酸化膜の厚みが薄いこと、クエン酸系の試薬を用いた場合には表面がTeリッチになることなどがXPS測定やAES測定より明らかになった。 今後は表面平坦性がエピタキシャル成長としても対応可能であると考えられる試薬を用いて表面処理を行い、その表面上に実際にZnTe層や量子ドット層等の成長を試み、どの処理方法が量子ドット形成に最適であるかを明らかにする予定である。

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海外研究活動

  • 多元系材料の開発技術の研究調査

    2010年04月
    -
    2010年09月

    ニュージーランド   カンタベリ大学

    アメリカ   アリゾナ大学

 

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担当経験のある科目(授業)

  • 電子材料学

    千葉大学  

  • 半導体デバイス

    千葉大学  

  • 電子材料学

    早稲田大学  

  • 電子回路

    早稲田大学  

  • 電子デバイス

    早稲田大学  

  • 電磁気学

    千葉大学  

  • 電磁気学

    早稲田大学  

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