Updated on 2022/10/01

写真a

 
IWASE, Eiji
 
Affiliation
Faculty of Science and Engineering, School of Fundamental Science and Engineering
Job title
Professor

Concurrent Post

  • Faculty of Science and Engineering   Graduate School of Fundamental Science and Engineering

Research Institute

  • 2020
    -
    2022

    理工学術院総合研究所   兼任研究員

Education

  • 2002.04
    -
    2005.03

    The University of Tokyo   Graduate School of Information Science and Technology   Dept. of Mechano-Informatics  

  •  
    -
    2005

    The University of Tokyo   Graduate School of Information Science and Technology   Department of Mechano-Informatics  

  • 2000.04
    -
    2002.03

    The University of Tokyo   Graduate School of Engineering   Dept. of Mechano-Informatics  

  •  
    -
    2002

    The University of Tokyo   Graduate School of Engineering   Department of Mechano-Informatics  

  • 1996.04
    -
    2000.03

    The University of Tokyo   School of Engineering   Dept. of Mechano-Informatics  

  •  
    -
    2000

    The University of Tokyo   Faculty of Engineering   Department of Mechano-Informatics  

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Degree

  • The University of Tokyo   Ph.D (Information Science and Technology)

Research Experience

  • 2019.04
    -
    Now

    Waseda University   Department of Applied Mechanics and Aerospace Engineering, School of Fundamental Science and Engineering, Faculty of Science and Technology   Professor (PI)

  • 2018.08
    -
    Now

    Ministry of Education, Culture, Sports, Science and Technology (MEXT)   Research Promotion Bureau   Senior Scientific Research Specialist (Concurrent Post)

  • 2014.04
    -
    2019.03

    Waseda University   Department of Applied Mechanics and Aerospace Engineering, School of Fundamental Science and Engineering, Faculty of Science and Technology   Associate Professor (PI)

  • 2012.04
    -
    2014.03

    Waseda University   Department of Applied Mechanics and Aerospace Engineering, School of Fundamental Science and Engineering, Faculty of Science and Technology   Assistant Professor (PI)

  • 2010.06
    -
    2012.03

    Harvard University   School of Engineering and Applied Sciences (SEAS)   Postdoctoral Fellow

  • 2007.04
    -
    2010.06

    The University of Tokyo   Dept. of Mechano-Informatics, Graduate School of Information Science and Technology   Assistant Professor

  • 2006.05
    -
    2007.03

    The University of Tokyo   Dept. of Mechano-Informatics, Graduate School of Information Science and Technology   Assistant Professor

  • 2006.04
    -
     

    The University of Tokyo   Dept. of Mechano-Informatics, Graduate School of Information Science and Technology   Technical Assistant

  • 2004.04
    -
    2006.03

    Japan Society for the Promotion Science (JSPS)   Research Fellow

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    (2011年10月より Harvard University, Wyss Institute for Biologically Inspired Engineering 兼担)

  •  
     
     

    (東京大学 工学部 機械情報工学科 兼担,2008年4月より 東京大学 IRT研究機構 兼担)

  •  
     
     

    (東京大学 工学部 機械情報工学科 兼担)

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Professional Memberships

  •  
     
     

    THE JAPAN SOCIETY OF APPLIED PHYSICS

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    電気学会

  •  
     
     

    Institute of Electrical and Electronics Engineers (IEEE)

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    日本ロボット学会

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    日本機械学会

  •  
     
     

    Optical Society of Japan (OSJ)

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    The Institute of Electrical Engineers of Japan (IEEJ)

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    Institute of Electrical and Electronics Engineers (IEEE)

  •  
     
     

    The Robotics Society of Japan (RSJ)

  •  
     
     

    The Japan Society of Mechanical Engineers (JSME)

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Research Areas

  • Robotics and intelligent system

  • Nano/micro-systems

  • Intelligent robotics

  • Mechanics and mechatronics

Research Interests

  • Micro-Electro-Mechanical Systems

Papers

  • Programming Stepwise Motility into a Sheet of Paper Using Inkjet Printing

    Hiroki Shigemune, Shingo Maeda, Eiji Iwase, Shuji Hashimoto, Shigeki Sugano, Hideyuki Sawada

    Advanced Intelligent Systems     2000153 - 2000153  2020.10

    DOI

  • Self-Healing Metal Interconnect for Flexible Electronic Device

    Tomoya Koshi, Eiji Iwase

    2019 International Conference on Electronics Packaging (ICEP)    2019.04

    DOI

  • High Performance Flexible Thermoelectric Device Included Rigid Material

    Makoto Kashiwagi, Tomoya Koshi, Eiji Iwase

    2019 IEEE 32nd International Conference on Micro Electro Mechanical Systems (MEMS)    2019.01

    DOI

  • Rapid prototyping of fluoropolymer microchannels by xurography for improved solvent resistance

    Takuma Hizawa, Atsushi Takano, Pravien Parthiban, Patrick S. Doyle, Eiji Iwase, Michinao Hashimoto

    Biomicrofluidics   12 ( 6 ) 064105 - 064105  2018.11  [Refereed]

    DOI

  • Design of Substrate Stretchability using Origami-Like Folding Deformation for Flexible Thermoelectric Generator

    Kana Fukuie, Yoshitaka Iwata, Eiji Iwase

    Micromachines   9 ( 3 ) 135  2018.06  [Refereed]

    DOI

  • Measurement of conformability and adhesion energy of polymeric ultrathin film to skin model

    Junki Sugano, Toshinori Fujie, Hiroyasu Iwata, Eiji Iwase

    Japanese Journal of Applied Physics   57 ( 6 ) 06HJ04  2018.06  [Refereed]

     View Summary

    We measured the conformability and adhesion energy of a polymeric ultrathin film "nanosheet" with hundreds of nanometer thickness to a skin model with epidermal depressions. To compare the confirmability of the nanosheets with different thicknesses and/or under different attaching conditions, we proposed a measurement method using skin models with the same surface profile and defined the surface strain ϵS as the quantified value of the conformability. Then, we measured the adhesion energy of the nanosheet at each conformability through a vertical tensile test. Experimental results indicate that the adhesion energy does not depend on the liquid used in wetting the nanosheet before attaching to the skin model and increases monotonously as the surface strain ϵS increases.

    DOI

  • Self-rolling up micro assembly using temperature - Responsive hydrogel sheet with rigid plate array

    Yoshitaka Iwata, Shuhei Miyashita, Eiji Iwase

    Proceedings of the IEEE International Conference on Micro Electro Mechanical Systems (MEMS)   2018-   93 - 96  2018.04  [Refereed]

     View Summary

    We propose a design method of a micro self-rolling up structure using a temperature-responsive hydrogel sheet with rigid plate array. Our self-rolling up is a method for developing a micro three-dimensional (3D) structure performed by rolling up a two-dimensional (2D) flat sheet, like making a croissant, through a continuous self-folding. The local curvature of the self-rolled up structure could be controlled by the length of rigid plates. By controlling the local curvature, we designed and developed self-rolled up structures with or without gaps between the self-rolled up layers, such as cylindrical and croissant-like ellipsoidal structures. In addition, all the structures demonstrated repetitive deformation of forward and backward rolling up by changing a temperature of water.

    DOI

  • Crack-configuration analysis of metal conductive track embedded in stretchable elastomer

    Tomoya Koshi, Eiji Iwase

    Micromachines   9 ( 3 ) 130  2018.03  [Refereed]

     View Summary

    This paper reports the analysis of the crack configuration of a stretched metal conductive track that is embedded in a stretchable elastomer. The factor determining the crack configurations is analyzed by modeling as well as experiments. The modeling analysis indicates that the crack configuration is determined by the ratio of the elongation stiffness of the track and elastomer, and is classified into two types: multiple-crack growth and single-crack growth. When the track stiffness is considerably lower than the elastomer stiffness, multiple-crack growth type occurs
    in the opposite case, single-crack growth type occurs. Hence, to verify the modeling analysis, metal conductive tracks with different thicknesses are fabricated, and the cracks are studied with respect to the crack width, number of cracks, and crack propagation speed. In this study, two conventional metal-track shapes are studied: straight-shaped tracks with track thickness of 0.04-1.17 μm, and wave-shaped tracks with track thickness of 2-10 μm. For straight-shaped tracks, multiple-crack growth type occurred, when the track thickness was 0.04 μm, and the crack configuration gradually changed to a single crack, with the increase in the track thickness. For wave-shaped tracks with track thickness of 2-10 μm, only single-crack growth type occurred
    however, the crack propagation speed decreased and the maximum stretchability of the track increased, with the increase in the track thickness.

    DOI

  • Electro-mechano-optical detection of nuclear magnetic resonance

    Kazuyuki Takeda, Kentaro Nagasaka, Atsushi Noguchi, Rekishu Yamazaki, Yasunobu Nakamura, Eiji Iwase, Jacob M. Taylor, Koji Usami

    Optica   5 ( 2 ) 152 - 158  2018.02  [Refereed]

     View Summary

    Signal reception of nuclear magnetic resonance (NMR) usually relies on electrical amplification of the electromotive force caused by nuclear induction. Here, we report up-conversion of a radio-frequency NMR signal to an optical regime using a high-stress silicon nitride membrane that interfaces the electrical detection circuit and an optical cavity through the electro-mechanical and the opto-mechanical couplings. This enables optical NMR detection without sacrificing the versatility of the traditional nuclear induction approach. While the signal-to-noise ratio is currently limited by the Brownian motion of the membrane as well as additional technical noise, we find it can exceed that of the conventional electrical schemes by increasing the electro-mechanical coupling strength. The electro-mechano-optical NMR detection presented here opens the possibility of mechanical parametric amplification of NMR signals. Moreover, it can potentially be combined with the laser cooling technique applied to nuclear spins.

    DOI

  • Structure design of electronic nanosheet for shortening skin-adhesive process

    N.SHINODA, S.MIYABAYASHI, E.IWASE, T.FUJIE, H.IWATA

    Proc. of the 9th Int, Conf. on Flexible and Printed Electronics (ICFPE2018)   accepted  2018  [Refereed]

  • Self-rolling up micro 3D structures using temperature-responsive hydrogel sheet

    Y. Iwata, S. Miyashita, E. Iwase

    JOURNAL OF MICROMECHANICS AND MICROENGINEERING   27 ( 12 ) 124003  2017.12  [Refereed]

     View Summary

    This paper proposes a micro self-folding using a self-rolling up deformation. In the fabrication method at micro scale, self-folding is an especially useful method of easily fabricating complex three-dimensional (3D) structures from engineered two-dimensional (2D) sheets. However, most self-folded structures are limited to 3D structures with a hollow region. Therefore, we made 3D structures with a small hollow region by self-rolling up a 2D sheet consisting of SU-8 and a temperature-responsive hybrid hydrogel of poly(N-isopropylacrylamide- co-acrylic acid) (pNIPAM-AAc). The temperature-responsive hydrogel can provide repetitive deformation, which is a good feature for micro soft robots or actuators, using hydrogel shrinking and swelling. Our micro self-rolling up method is a self-folding method for a 3D structure performed by rolling up a 2D flat sheet, like making a croissant, through continuous self-folding. We used our method to fabricate 3D structures with a small hollow region, such as cylindrical, conical, and croissant-like ellipsoidal structures, and 3D structures with a hollow region, such as spiral shapes. All the structures showed repetitive deformation, forward rolling up in 20 degrees C cold water and backward rolling up in 40 degrees C hot water. The results demonstrate that self-rolling up deformation can be useful in the field of micro soft devices.

    DOI

  • Effect of Living Body on Performance of RF Identifier Antenna Printed on Ultrathin Polymer Film

    H.HAYATA, M.OKAMOTO, S.TAKEOKA, E.IWASE, T.FUJIE, H.IWATA

    International Conference on Flexible and Printed Electronics (ICFPE 2017)   paper no. P083  2017.09  [Refereed]

  • Epidermal pH-sensor capable of operating only with NFC energy harvesting

    S.MIYABAYASHI, H.HAYATA, E.IWASE, T.FUJIE, H.IWATA

    International Conference on Flexible and Printed Electronics (ICFPE 2017)   paper no. P082  2017.09  [Refereed]

  • Voltage and current conditions for nanoparticle chain formation using dielectrophoresis

    Tomoya Koshi, Yuta Nakajima, Eiji Iwase

    MICRO & NANO LETTERS   12 ( 8 ) 532 - 535  2017.08  [Refereed]

     View Summary

    Here, the voltage and current conditions required to form a nanoparticle chain bridging a gap between electrodes that is several tens of micrometres wide have been examined. When a voltage is applied to a gap between electrodes covered with a dispersion of nanoparticles, the nanoparticles are trapped in the gap by dielectrophoresis, forming a nanoparticle chain. It has been considered that a nanoparticle chain is formed in a gap only when a voltage higher than a certain value with a current lower than a certain value is applied to the gap. In this work, certain voltages were first applied with changing current to a 10 mu m-wide gap between electrodes covered with a dispersion of 150 nm-diameter gold nanoparticles, and they found that a nanoparticle chain was formed only when 6.1 V-rms or more with 15 mA(rms) or less was applied. Next, the process of nanoparticle chain formation in a 10 mu m-wide gap was directly observed with high-magnification and high-speed microscopy, and they clarified the behaviour of nanoparticle chain formation when a low voltage, high voltage with high current, and high voltage with low current were applied. Finally, they measured the critical value of current for nanoparticle chain formation in a gap several tens of micrometres wide.

    DOI

  • Sample shape design for a micro-volume NMR spectroscopy

    Takuma Hizawa, Masato Takahashi, Eiji Iwase

    MICRO & NANO LETTERS   12 ( 8 ) 550 - 553  2017.08  [Refereed]

     View Summary

    The authors examined a shape of sample on micro-volume, which is a several L, nuclear magnetic resonance (NMR) spectroscopy in order to obtain uniformed magnetic flux density in the sample and a sharp NMR spectrum by using a conventional NMR apparatus. Firstly, they simulated the magnetic flux density distribution in spherical and cubic shaped samples and calculated NMR spectra from each shape. The simulated NMR spectra from spherical samples were sharp enough, being <0.1 ppb in a full width at half maximum (FWHM). On the other hand, the simulated NMR spectra from cubic samples were much broader than those from spherical samples. Then, they made polydimethylsiloxane sample chambers with spherical or cubic sample of several mu L in volume and they evaluated NMR spectra from those micro-volume sample chambers. As a result, they obtained a sharp NMR spectrum with FWHM of 2 ppb from the sample chamber with the spherical sample, and a broad spectrum with FWHM of 220 ppb from the sample chamber with the cubic sample. These results indicate that the spherical shape is essential to obtain a shape spectrum in micro-volume NMR spectroscopy by using a conventional NMR apparatus.

    DOI

  • Operation of three-dimensional MEMS mirror by single superposed driving signal

    Toshiya Nagasawa, Yohei Oguchi, Eiji Iwase

    JAPANESE JOURNAL OF APPLIED PHYSICS   56 ( 6 ) 06GN12  2017.06  [Refereed]

     View Summary

    We have realized a three-dimensional (3D) operation of a microelectromechanical systems (MEMS) mirror with three resonant modes and a single driving apparatus by a single superposed signal with three frequencies. We fabricated a 3D MEMS mirror with a single pair of beams having three resonant modes (x-and y-axis rotational modes and a z-axis vertical mode). We demonstrated the 3D operation by a single driving apparatus using the Lorentz force. In addition, we have shown that the x-and y-axis rotational angles and z-axis vertical displacement are proportional to the voltage amplitudes of each resonant frequency in the superposed signal, and the proportionality constants for each angle and deformation are approximately determined as 0.10 degrees/V, 0.10 degrees/V, and 70nm/V, respectively. This result indicates that the mechanical amplitude of each mode is easy to control by the signal amplitude of each resonant frequency in the superposed signal. (C) 2017 The Japan Society of Applied Physics

    DOI

  • Micropatterning of Multiple Photonic Colloidal Crystal Gels for Flexible Structural Color Films

    Noriyuki Suzuki, Eiji Iwase, Hiroaki Onoe

    LANGMUIR   33 ( 24 ) 6102 - 6107  2017.06  [Refereed]

     View Summary

    We herein report the micropatterning of flexible multiple photonic colloidal crystal gels (PCCGs) using single-layered microchannels. These patterned PCCGs exhibit structural colors that can be tuned by adjustment of the diameter and concentration of the colloidal particles in precursor solutions of N-isopropylacrylamide (NIPAM) or polyethylene glycol diacrylate (PEGDA). The precursor solutions containing dispersed colloidal particles were selectively injected into single-layered microchannels where they polymerized rapidly. The shape, density, and height of the patterned PCCG pixels were determined by the microchannels, which in turn determined the optical properties of the PCCG arrays. Furthermore, the preparation of three different types of PCCGs exhibiting three different structural colors at a high pixel density was demonstrated successfully using the single-layered polydimethylsiloxane (PDMS) microchannels. Finally, the optical reflective properties and the mechanical flexibility of the patterned multiple PCCG arrays were evaluated. We expect that our method for the preparation of such patterned PCCG arrays will contribute to the development of flexible optical devices.

    DOI

  • Printed high-frequency RF identification antenna on ultrathin polymer film by simple production process for soft-surface adhesive device

    Hiroki Hayata, Marin Okamoto, Shinji Takeoka, Eiji Iwase, Toshinori Fujie, Hiroyasu Iwata

    JAPANESE JOURNAL OF APPLIED PHYSICS   56 ( 5 ) 05EC01  2017.05  [Refereed]

     View Summary

    In this paper, we present a simple method for manufacturing electronic devices using ultrathin polymer films, and develop a high-frequency RF identification. To expand the market for flexible devices, it is important to enhance their adhesiveness and conformability to surfaces, to simplify their fabrication, and to reduce their cost. We developed a method to design an antenna for use on an operable RF identification whose wiring was subjected to commercially available inkjet or simple screen printing, and successfully fabricated the RF identification. By using ultrathin films made of polystyrene-block-polybutadiene-block-polystyrene (SBS) as substrates-less than 750nm-the films could be attached to various surfaces, including soft surfaces, by van der Waals force and without using glue. We succeeded in the simple fabrication of an ultrathin RF identification including a commercial or simple printing process. (C) 2017 The Japan Society of Applied Physics

    DOI

  • Printed Paper Robot Driven by Electrostatic Actuator

    Hiroki Shigemune, Shingo Maeda, Vito Cacucciolo, Yoshitaka Iwata, Eiji Iwase, Shuji Hashimoto, Shigeki Sugano

    IEEE Robotics and Automation Letters   2 ( 2 ) 1001 - 1007  2017.04  [Refereed]

     View Summary

    © 2017 IEEE. Effective design and fabrication of 3-D electronic circuits are among the most pressing issues for future engineering. Although a variety of flexible devices have been developed, most of them are still designed two-dimensionally. In this letter, we introduce a novel idea to fabricate a 3-D wiring board. We produced the 3-D wiring board from one desktop inkjet printer by printing conductive pattern and a 2-D pattern to induce self-folding. We printed silver ink onto a paper to realize the conductive trace. Meanwhile, a 3-D structure was constructed with self-folding induced by water-based ink printed from the same printer. The paper with the silver ink self-folds along the printed line. The printed silver ink is sufficiently thin to be flexible. Even if the silver ink is already printed, the paper can self-fold or self-bend to consist the 3-D wiring board. A paper scratch driven robot was developed using this method. The robot traveled 56 mm in 15 s according to the vibration induced by the electrostatic force of the printed electrode. The size of the robot is 30 × 15 × 10 mm. This work proposes a new method to design 3-D wiring board, and shows extended possibilities for printed paper mechatronics.

    DOI

  • Microfluidically Patterned Dome-Shaped Photonic Colloidal Crystals Exhibiting Structural Colors with Low Angle Dependency

    Noriyuki Suzuki, Eiji Iwase, Hiroaki Onoe

    ADVANCED OPTICAL MATERIALS   5 ( 4 ) 1600900  2017.02  [Refereed]

    DOI

  • Sandwich fixation of electronic elements using free-standing elastomeric nanosheets for low-temperature device processes

    Marin Okamoto, Mizuho Kurotobi, Shinji Takeoka, Junki Sugano, Eiji Iwase, Hiroyasu Iwata, Toshinori Fujie

    JOURNAL OF MATERIALS CHEMISTRY C   5 ( 6 ) 1321 - 1327  2017.02  [Refereed]

     View Summary

    We fabricated free-standing, flexible and physically adhesive ultrathin elastomeric films (nanosheets) for application as electronic substrates and packaging films. In this work, electronic elements such as a chip resistor and a chip LED were sandwiched between elastomeric nanosheets of less than 1 mu m thickness to obtain electrical conduction in silver lines that were inkjet-printed on the nanosheet. This sandwich-fixation process contributed to the development of an electronic device showing conformable adhesion and operation on the skin surface.

    DOI

  • Flexible Coloring Element by Using Bending Deformation of Electroactive Hydrogel

    Kodai Usuki, Hiroaki Onoe, Eiji Iwase

    ELECTRONICS AND COMMUNICATIONS IN JAPAN   100 ( 1 ) 44 - 48  2017.01  [Refereed]

     View Summary

    We demonstrated coloring elements with high ratio change of the coloring area by using bending deformation of electroactive hydrogel. By using the nondimensional deflection of a gel, we showed that the response time for the color change and the thickness of the coloring element can be designed. We fabricated a 3 x 3 dot-matrix display with of 0.56 and evaluated the performance of the coloring element. As a result, the coloring area ratios in black state and colored state were 7.64 +/- 4.6% and 92.1 +/- 4.6%, respectively. The response times were 12 s from blank state to colored state, and 13 s from colored state to blank state.

    DOI

  • Arrangement of Divided Dihedral Corner Reflector Array for Wide Viewing Angle of Floating Image using Retrotransmission

    YOSHIMIZU Yuta, IWASE Eiji

    The Proceedings of JSME annual Conference on Robotics and Mechatronics (Robomec)   2017   2A1 - K10  2017

     View Summary

    <p>We proposed divided-type dihedral corner reflector array (DCRA) in order to display floating image with wide viewing angle. DCRA is a kind of optical device which can display floating image of real object by retrotransmission. The viewing angle of the floating image is, however, narrow, because the angle of incident ray which can be retrotransmission is limited. Therefore, we expand a range of viewing angle by dividing and combining DCRA to use the region in which the ray can be retrotransmission. In this paper, we evaluated the viewing angle of our divided DCRA by analyzing angular distribution of retrotransmissive ratio. As a result, we showed that the divided DCRA can be expanded the viewing angle of floating image to 180 deg.</p>

    DOI CiNii

  • Improvement of Stretchability using Ratio of Stiffness between Metal and Substrate for Stretchable Electronic Device

    ISHII Tomoyuki, PARK Chije, KOSHI Tomoya, IWASE Eiji

    The Proceedings of JSME annual Conference on Robotics and Mechatronics (Robomec)   2017   1P2 - K10  2017

     View Summary

    <p>We investigated an effect of an elongation stiffness of a substrate and a metal wire to stretchability of a wavy metal wire. We focused on a ratio of the elongation stiffness of the substrate to that of the metal wire. In tensile test using two kinds of wavy specimens, most of the results showed increase of the maximum elongation at increase of the elongation stiffness ratio. When the elongation stiffness ratio is changed from 0 to 0.910, the stretchability is increased from 0.322 to 0.594 and from 0.337 to 0.425. This result suggests that stretchability can be improved by designing the elongation stiffness ratio.</p>

    DOI CiNii

  • Fabrication and Measurement of Mechanical Resonator with Large Freestanding Nanomembrane

    OSAMURA Toru, IWASE Eiji

    The Proceedings of JSME annual Conference on Robotics and Mechatronics (Robomec)   2017   1A1 - M11  2017

     View Summary

    <p>Our goal is to realize a mechanical resonator with large freestanding nanomembrane. First of all, we measured residual stress caused by deposition of gold layer and designed the thickness of the gold layer on the nanomenbrane as 500 nm. Then, we practically fabricated and measured a structure of a nanomechanical resonator with a 500-nm-thick gold layer on a 50-nm-thick silicon nitride nanomembrane. In the part of freestanding nanomembrane, there was no breaks nor bucking, and roughness of the surface was less than 100 nm. The average height of pillars was 578 nm. Finally, we measured that the resonant frequency of the fabricated structure was 188.83 kHz and the Quality factor was 797 in the atmosphere.</p>

    DOI CiNii

  • Fabrication and Evaluation of Heat Conduction Skin Moisture Sensor with Multiple Temperature Measuring Parts

    FUKUIE Kana, IWASE Eiji

    The Proceedings of JSME annual Conference on Robotics and Mechatronics (Robomec)   2017   1A1 - J10  2017

     View Summary

    <p>We proposed a skin moisture sensor with multiple temperature measuring parts for self-calibration. A resistance temperature detector (RTD) can be used for both heat source and temperature measurement. We fabricated a device with four RTDs to measure the skin moisture content. The temperature coefficients of resistance of the fabricated RTDs are almost the same. On the other hand, a fluctuation of temperature rise was, however, observed. Therefore, we proposed a method of self-calibration of the difference in the calorific value of the heat source by the temperature rise measured by the heat source. By using the proposed method, we showed that the temperature rise fluctuation measured by the resistance can be reduced.</p>

    DOI CiNii

  • STRETCHABLE ELECTRONIC DEVICE WITH REPEAT SELF-HEALING ABILITY OF METAL WIRE

    Tomoya Koshi, Eiji Iwase

    30TH IEEE INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS (MEMS 2017)     262 - 265  2017  [Refereed]

     View Summary

    This paper reports a stretchable electronic device with repeat self-healing ability of a wire crack caused by stretching deformation. The crack of metal wire is healed with assembled metal nanoparticles by dielectrophoresis, when a voltage is applied to the cracked wire covered with the nanoparticle solution. By designing a circuit, we controlled the applied voltage and current for the self-healing to be avoid excessive Joule heating in the assembled nanoparticles. This consideration enables us to heal a crack of tens of micrometers in width and to practically achieve a stretchable electronic device.

  • STRESS-FREE STRETCHABLE ELECTRONIC DEVICE USING FOLDING DEFORMATION

    Yoshitaka Iwata, Eiji Iwase

    30TH IEEE INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS (MEMS 2017)     231 - 234  2017  [Refereed]

     View Summary

    We developed a two-dimensionally (2-D) stretchable electronic device with stress-free region by applying origami folding. The key idea is to achieve "a stretching deformation of whole device" by "a local bending deformation". Because our device has stress-free region, we can use a rigid chip (such as LED chips and MEMS sensors) and a metal wire without mechanical fracture or metal fatigue. In this paper, first, we proposed a 2-D stretchable structure by developing "miura-ori" folding. Next, we fabricated a 2-D stretchable electronic device, and confirmed that wire fatigue or cracks are not generated by repeated deformation. Finally, we demonstrated 2-D stretchability and bendability using the device with inorganic LED chips.

  • HYBRID FILM FOR SELF-ADHESION AND SHAPE-CONTROLLING

    Sota Shimbo, Toshinori Fujie, Eiji Iwase

    30TH IEEE INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS (MEMS 2017)     624 - 627  2017  [Refereed]

     View Summary

    We report a hybrid film that is composed of "polymer nanosheet" with a hundreds-of-nanometer-thick film and "punched film" with hundreds-of-micrometer-thick film. Because of the thickness, the nanosheet is able to adhere to biological tissues without a glue, but is sometimes difficult to handling. Our hybrid film is established both adhesiveness of the nanosheet and shape-controlling ability of the punched film. In this paper, first, we fabricated the cylindrical-shaped hybrid film. Next, we achieved the hybrid film unfold into flat shape. Finally, we evaluated the adhesion force of the hybrid film and confirmed that the hybrid film can adhere to biological tissues.

  • Dynamic transformation of self-assembled structures using anisotropic magnetized hydrogel microparticles

    Satoru Yoshida, Masahiro Takinoue, Eiji Iwase, Hiroaki Onoe

    JOURNAL OF APPLIED PHYSICS   120 ( 8 ) 084905  2016.08  [Refereed]

     View Summary

    This paper describes a system through which the self-assembly of anisotropic hydrogel microparticles is achieved, which also enables dynamic transformation of the assembled structures. Using a centrifuge-based microfluidic device, anisotropic hydrogel microparticles encapsulating superparamagnetic materials on one side are fabricated, which respond to a magnetic field. We successfully achieve dynamic assembly using these hydrogel microparticles and realize three different self-assembled structures (single and double pearl chain structures, and close-packed structures), which can be transformed to other structures dynamically via tuning of the precessional magnetic field. We believe that the developed system has potential application as an effective platform for a dynamic cell manipulation and cultivation system, in biomimetic autonomous microrobot organization, and that it can facilitate further understanding of the self-organization and complex systems observed in nature. Published by AIP Publishing.

    DOI

  • Sheet shape-controlling method for hundreds-of-nanometer-thick polymer film using soluble polymer layer

    Sota Shimbo, Toshinori Fujie, Eiji Iwase

    JAPANESE JOURNAL OF APPLIED PHYSICS   55 ( 6 ) 06GP21  2016.06  [Refereed]

     View Summary

    We proposed a sheet shape-controlling method for a hundreds-of-nanometers-thick polymeric ultrathin film (referred to as a "nanosheet") for folding the film into a cylindrical shape and unfolding the film into a flat shape. To control the shape of the nanosheet, we used a triple-layered structure, which included a nanosheet and additional two layers of a water-soluble polymer. The additional two layers are thicker than the nanosheet, and one of the two layers was loaded to prestretch that layer. Therefore, the triple-layered structure was folded into a cylindrical shape owing to strain mismatch between the two layers and unfolded into a flat shape after the dissolution of the two layers. In this study, we could successfully estimate the radius of curvature of the triple-layered structure by considering the strain mismatch between the two layers. In addition, we confirmed that the triple-layered structure unfolded into a flat shape by the dissolution of the two layers. (C) 2016 The Japan Society of Applied Physics

    DOI

  • Particle Size Dependence on Self-Healing Metal Wire using an Electric Field Trapping of Metal Nanoparticles

    古志知也, 岩瀬英治

    日本機械学会論文集   82 ( 834 ) 15-00470  2016.02  [Refereed]

     View Summary

    On a metal wire with a self-healing function of a crack using electric field trapping of metal nanoparticles, we examined a healable crack width by using the different particle size. The electric field trapping is a phenomenon where the nanoparticles are trapped in the crack by the electric field in the region of the crack only, when a voltage is applied to the cracked wire covered with the nanoparticle solution. In this paper, first, we theoretically analyzed and calculated the particle size dependence of forces acting on the nanoparticles. Next, we fabricated gold wires with patterned cracks on a glass substrate, and measured the healable crack width by comparing 20 nm, 100 nm and 200 nm in particle radius. In the experiments, gold nanoparticles aqueous solution was used as nanoparticles solution. As a result, in the each case of 20 nm, 100 nm and 200 nm in particle radius, cracks up to 1.5 μm, 2.5 μm and 4.0 μm were successfully healed by applying less than 4.2 V in amplitude and 100 kHz in frequency of AC voltage, respectively. These results indicate that the larger nanoparticle can heal the wider crack with the same cross-sectional shape of the wire and the approximately same applied voltage. After the experiments, we confirmed that assembled nanoparticles were bridging the crack at the inside of the crack through scanning electron microscope (SEM) observations.

    DOI CiNii

  • MICROFLUIDIC PATTERNING OF HEMISPHERICAL DOME-SHAPE PHOTONIC COLLOIDAL CRYSTALS FOR WIDE-VIEWING-ANGLE REFLECTIVE DISPLAY

    Noriyuki Suzuki, Eiji Iwase, Hiroaki Onoe

    2016 IEEE 29TH INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS (MEMS)     613 - 616  2016  [Refereed]

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    This paper describes a micropatterning method of hemispherical dome shape photonic colloidal crystals (PCCs) in microchannels for a wide-viewing-angle optical color filter of a reflective display. We fabricated hemispherical dome-top PDMS microchannels and crystalized colloidal particles inside the microchannel. These dome-shape micorchannels enable us to observe reflected light (structural color) from the PCCs in wide viewing-angle (Fig. I). We succeeded in patterning of two types of hemispherical PCCs in the dome-top micorchannels, and confirmed that those patterned PCCs reflected their structural color in wide-viewing-angle. Our patterning method could be effective to realize an optical filter for full-color, wide-viewing-angle and low-energy consumption reflective displays

  • Development of Inexpensive Skin Adhesive Electronic Device - RFID Tag Implementation on Ultrathin Polymer Film -

    H.HAYATA, M.OKAMOTO, S.TAKEOKA, E.IWASE, T.FUJIE, H.IWATA

    Int. Conf. on Flexible and Printed Electronics   O5-4  2016  [Refereed]

  • The design of MEMS scanner for the three dimensional actuation with a pair of beams

    Yohei Oguchi, Chisa Iino, Eiji Iwase

    IEEJ Transactions on Sensors and Micromachines   136 ( 10 ) 448 - 453  2016  [Refereed]

     View Summary

    We propose the design for three-dimensional (3-D) scanning micromirror with single pair of beams. A 3-D scanning micromirror is powerful solution for projection/detection of a 3-D image in tiny devices. We succeed in designing and fabricating the micromirror having three separated resonance modes (two torsion modes and one parallel mode) with high fill-factor. Our design of single pair of beams can contribute to simpleness and compactness of a 3-D scanner because of easy fabrication and high fill-factor.

    DOI

  • Flexible coloring element by using bending deformation of electroactive hydrogel

    Kodai Usuki, Hiroaki Onoe, Eiji Iwase

    IEEJ Transactions on Sensors and Micromachines   135 ( 12 ) 480 - 483  2015.12  [Refereed]

     View Summary

    We demonstrated coloring elements with high ratio change of the coloring area by using bending deformation of electroactive hydrogel. By using the nondimensional deflection α of a gel, we showed that the response time for the color change and the thickness of the coloring element can be designed. We fabricated a 3 × 3 dot-matrix display with α of 0.56 and evaluated the performance of the coloring element. As a result, the coloring area ratios in blank state and colored state were 7.6±4.6% and 92.1±4.6%, respectively. The response times were 12 seconds from blank state to colored state, and 13 seconds from colored state to blank state.

    DOI

  • Moisture sensor based on heat transfer possessing insusceptibility to coating materials on skin

    Minako Hosono, Akihiro Isozaki, Koki Katoh, Yasumasa Ichikawa, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    SENSORS AND ACTUATORS A-PHYSICAL   235   265 - 272  2015.11  [Refereed]

     View Summary

    This paper presents a thermal-based skin moisture sensor that is insusceptible to thin coating materials on skin. To realize this sensor, numerical simulations are performed to evaluate the influence of surface-coating materials, such as Vaseline moisturizer, on the heat transfer from a heat source in the sensor to the skin. The simulation results show that the influence of the thin Vaseline layer on the temperature change of the heat source is negligible, but the existence of air gaps between the sensor and the skin drastically interrupts the heat transfer. Considering the simulation results, the thermal-based skin moisture sensor is designed and fabricated with a microelectromechanical systems (MEMS) pressure sensor to avoid heat transfer interruption due to air gaps. The measurement results of water content in a water-absorbing polymer, covered with a 10-mu m-thick polyethylene film, show that the moisture sensor can assess the water content of materials that are covered with a thin layer. Finally, we demonstrate the hydration measurement of skin with Vaseline coating. The measurement results confirm the potential of the moisture sensor to measure the water content of skin covered with moisturizing substances. (C) 2015 Elsevier B.V. All rights reserved.

    DOI

  • Deformable coloring element using an electroactive hydrogel with bottom-arranged electrodes

    Kodai Usuki, Hiroaki Onoe, Eiji Iwase

    JAPANESE JOURNAL OF APPLIED PHYSICS   54 ( 6 )  2015.06  [Refereed]

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    By using an electroactive hydrogel, we proposed and fabricated a deformable coloring element. The proposed element is composed of a dyed electroactive hydrogel piece and bottom-arranged electrodes. By using the bottom arrangement of electrodes, we can use a simple fabrication and achieve a high fill factor (FF). To design the element, we analyzed the electric field in various dimensions of the electrodes by using a charge simulation method. The bending factor (BF) was defined as an index of bending direction and speed of the gel. From the difference between the BFs for each dimension, we found the optimal parameters required to maximize BF on the chosen boundary condition of FF &gt;= 0.9. We then determined the dimensions of a coloring element on the basis of the results of the analysis. Finally, a 3 x 3 dot-matrix display was fabricated to demonstrate a color change in all nine cells. (C) 2015 The Japan Society of Applied Physics

    DOI

  • Self-healing metal wire using electric field trapping of metal nanoparticles

    Tomoya Koshi, Eiji Iwase

    JAPANESE JOURNAL OF APPLIED PHYSICS   54 ( 6 ) 06FP03  2015.06  [Refereed]

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    We propose a self-healing metal wire using electric field trapping of gold nanoparticles by a dielectrophoresis force. A cracked gold wire can retrieve its conductivity through the self-healing function. In this paper, we examine the healing voltage causing the electric field trapping and determine the healing time, which is relevant to future device applications. First, the forces acting on a nanoparticle are analyzed and a theoretical healing voltage curve is calculated. Then, gold wires with 200- to 1,600-nm-wide cracks are fabricated on glass substrate and the self-healing function is verified through healing experiments. As a result, gold wires with cracks of up to 1,200 nm in width are successfully healed by applying less than similar to 2.5 V (on average), and the experimental results correspond almost exactly with the calculated healing voltage curve. The average healing times are 10 to 285 s for 200- to 1,200-nm-wide cracks. Through scanning electron microscope analysis after the healing experiments, we confirm that the cracks are healed by assembled nanoparticles. (C) 2015 The Japan Society of Applied Physics

    DOI

  • SELF-HEALING METAL WIRE USING AN ELECTRIC FIELD TRAPPING OF GOLD NANOPARTICLES FOR FLEXIBLE DEVICES

    Tomoya Koshi, Eiji Iwase

    2015 28TH IEEE INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS (MEMS 2015)     81 - 84  2015  [Refereed]

     View Summary

    We developed a self-healing metal wire using an electric field trapping of gold nanoparticles. A cracked metal wire on a stretchable substrate can get its conductivity again by the self-healing function. In this paper, first, we theoretically analyzed force acting on a nanoparticle and calculated a critical voltage which cause the electric field trapping. Next, we fabricated gold wires with artificially patterned cracks on a glass substrate and verified the self-healing function by experiments of a crack healing. Finally, we demonstrated the self-healing of a cracked metal wire on a stretchable substrate to show a usefulness of the self-healing for flexible devices.

  • Strong Mechanical Nonlinearity of Optomechanically Driven Suspended Photonic Crystal Membrane

    Pui-Chuen Hui, Alejandro Rodriguez, David Woolf, Eiji Iwase, Mughees Khan, Federico Capasso, Marko Loncar

    2015 CONFERENCE ON LASERS AND ELECTRO-OPTICS (CLEO)    2015  [Refereed]

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    We demonstrated the nonlinear mechanics of an optomechnaically driven silicon membrane suspended 100nm over a nearby substrate. The estimated optical force-induced Duffing nonlinearity is 10(28)Hz(2)/m(2), significantly larger than that afforded by the nonlinear Casimir potential.

  • MICROPATTERNING OF MULTIPLE PHOTONIC COLLOIDAL CRYSTALS IN SINGLE-LAYERED MICROCHANNELS FOR STRUCTURAL-COLOR OPTICAL FILTER

    Noriyuki Suzuki, Eiji Iwase, Hiroaki Onoe

    2015 TRANSDUCERS - 2015 18TH INTERNATIONAL CONFERENCE ON SOLID-STATE SENSORS, ACTUATORS AND MICROSYSTEMS (TRANSDUCERS)     407 - 410  2015  [Refereed]

     View Summary

    We describe a simple and rapid micropatterning method of multiple types of photonic colloidal crystals (PCCs) on a single substrate for an optical color filter of a reflective display. We developed a "Channel-Cut Method" to introduce multiple colloidal suspensions selectively and sequentially into a microchannel network. By combining this method with centrifugal crystallization, we succeeded in patterning of two different PCCs made of silica or polystylene in a single-layered microchannel. We believe that our method could contribute to develop a colorized reflective display that achieves low energy consumption and high color expression.

  • Stretchable cell culture platforms using micropneumatic actuators

    Yun Jung Heo, Tetsuo Kan, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    MICRO & NANO LETTERS   8 ( 12 ) 865 - 868  2013.12  [Refereed]

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    A stretchable cell culture platform in which elastic micropneumatic actuators are embedded has been developed. By using the softlithography of polydimethylsiloxane (PDMS), the platform can be fabricated to any size and shape. It also permits cell culture by using the same standard methods that one would use with a Petri dish and it is transparent, permitting optical inspection of the cells. Thus, the platform is promising for studying cell responses because of mechanical stimulus. In this reported work, cells were cultured on a PDMS diaphragm of the micropneumatic actuators. Owing to input pressure, the micropneumatic actuators swell like a balloon, thereby stretching the cell membranes on the PDMS. The design flexibility of the presented approach is demonstrated by developing two kinds of stretchable platforms with diaphragm diameters of 558 and 24.8 m to stretch whole and local cell membranes, respectively. Then, the cell membranes attached on the PDMS diaphragms are stretched by applying pressure on the pneumatic actuators. The applied stress causes an increase in the intracellular calcium ion concentration that is a fast cellular mechanotransduction. Therefore, it is concluded that the method for stretching cell membranes can stimulate either whole or local cell membranes, thus showing the potential to be used in in vitro studies of cellular mechanotransduction.

    DOI

  • Optical bistability with a repulsive optical force in coupled silicon photonic crystal membranes

    Pui-Chuen Hui, David Woolf, Eiji Iwase, Young-Ik Sohn, Daniel Ramos, Mughees Khan, Alejandro W. Rodriguez, Steven G. Johnson, Federico Capasso, Marko Loncar

    APPLIED PHYSICS LETTERS   103 ( 2 ) 21102  2013.07  [Refereed]

     View Summary

    We demonstrate actuation of a silicon photonic crystal membrane with a repulsive optical gradient force. The extent of the static actuation is extracted by examining the optical bistability as a combination of the optomechanical, thermo-optic, and photo-thermo-mechanical effects using coupled-mode theory. Device behavior is dominated by a repulsive optical force which results in displacements of approximate to 1 nm/mW. By employing an extended guided resonance which effectively eliminates multi-photon thermal and electronic nonlinearities, our silicon-based device provides a simple, non-intrusive solution to extending the actuation range of micro-electromechanical devices. (C) 2013 AIP Publishing LLC.

    DOI

  • A photoresponse-compensated parallel piezoresistive cantilever for cellular force measurements

    Uijin G. Jung, Kenta Kuwana, Yoshiharu Ajiki, Hidetoshi Takahashi, Tetsuo Kan, Yusuke Takei, Kentaro Noda, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Journal of Micromechanics and Microengineering   23 ( 4 ) 45015  2013.04  [Refereed]

     View Summary

    This paper describes a parallel piezoresistive cantilever that is composed of a force-sensing cantilever in addition to a reference cantilever for photoresponse compensation. Piezoresistive cantilevers have been applied in many cellular mechanical measurement studies because of their high sensitivity, high time resolution and ease of handling. However, the electrical resistance changes in response to the excitation light of the fluorescence microscope, which affects the cell measurements. We measured the I-V characteristics of a piezoresistive layer. These photoresponses occurred due to the internal photoelectric effect. We canceled the photoresponses using the reference cantilever. This paper demonstrates compensation of the cantilever photoresponse under irradiation at different angles, wavelengths and light intensities. As a result, the photoresponse could be decreased by 87%. © 2013 IOP Publishing Ltd.

    DOI

  • Optomechanical and photothermal interactions in suspended photonic crystal membranes

    David Woolf, Pui-Chuen Hui, Eiji Iwase, Mughees Khan, Alejandro W. Rodriguez, Parag Deotare, Irfan Bulu, Steven G. Johnson, Federico Capasso, Marko Loncar

    OPTICS EXPRESS   21 ( 6 ) 7258 - 7275  2013.03  [Refereed]

     View Summary

    We present here an optomechanical system fabricated with novel stress management techniques that allow us to suspend an ultrathin defect-free silicon photonic-crystal membrane above a Silicon-on-Insulator (SOI) substrate with a gap that is tunable to below 200 nm. Our devices are able to generate strong attractive and repulsive optical forces over a large surface area with simple in-and out-coupling and feature the strongest repulsive optomechanical coupling in any geometry to date (g(OM)/2 pi approximate to -65 GHz/nm). The interplay between the optomechanical and photo-thermal-mechanical dynamics is explored, and the latter is used to achieve cooling and amplification of the mechanical mode, demonstrating that our platform is well-suited for potential applications in low-power mass, force, and refractive-index sensing as well as optomechanical accelerometry. (C) 2013 Optical Society of America

    DOI

  • Flexible tactile sensor for shear stress measurement using transferred sub-mu m-thick Si piezoresistive cantilevers

    Kentaro Noda, Hiroaki Onoe, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    JOURNAL OF MICROMECHANICS AND MICROENGINEERING   22 ( 11 ) 115025  2012.11  [Refereed]

     View Summary

    We propose a flexible tactile sensor using sub-mu m-thick Si piezoresistive cantilevers for shear stress detection. The thin Si piezoresistive cantilevers were fabricated on the device layer of a silicon on insulator (SOI) wafer. By using an adhesion-based transfer method, only these thin and fragile cantilevers were transferred from the rigid handling layer of the SOI wafer to the polydimethylsiloxane layer without damage. Because the thin Si cantilevers have high durability of bending, the proposed sensor can be attached to a thin rod-type structure serving as the finger of a robotic hand. The cantilevers were arrayed in orthogonal directions to measure the X and Y directional components of applied shear stresses independently. We evaluated the bending durability of our flexible tactile sensor and confirmed that the sensor can be attached to a rod with a radius of 10 mm. The sensitivity of the flexible tactile sensor attached to a curved surface was 1.7 x 10(-6) Pa-1 on average for a range of shear stresses from -1.8 x 10(3) to 1.8 x 10(3) Pa applied along its surface. It independently detected the X and Y directional components of the applied shear stresses.

    DOI

  • MEMS microphone with a micro Helmholtz resonator

    Hidetoshi Takahashi, Akira Suzuki, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    JOURNAL OF MICROMECHANICS AND MICROENGINEERING   22 ( 8 ) 085019  2012.08  [Refereed]

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    This paper reports on the development of a micro electro mechanical system microphone consisting of a piezoresistive cantilever and a micro HR (Helmholtz resonator) for use as an ultrasonic proximity sensor. The resonance frequency of the HR was designed to be equal to that of the cantilever. Therefore, the HR increases the sensitivity of the microphone to ultrasonic waves. The dimensions of the fabricated HR and the cantilever are 1.2 mm x 1.2 mm x 0.6 mm and 130 mu m x 40 mu m x 0.3 mu m, respectively. At a resonance frequency of 22.6 kHz, the cantilever with the HR detected ultrasonic waves with 14 times greater sensitivity than that of the cantilever without the HR. We demonstrated that the fabricated sensor is capable of measuring distances between 0.5 and 6.0 m.

    DOI

  • Control of buckling in large micromembranes using engineered support structures

    Eiji Iwase, Pui-Chuen Hui, David Woolf, Alejandro W. Rodriguez, Steven G. Johnson, Federico Capasso, Marko Loncar

    JOURNAL OF MICROMECHANICS AND MICROENGINEERING   22 ( 6 ) 065028  2012.06  [Refereed]

     View Summary

    In this paper we describe a general method to avoid stress-induced buckling of thin and large freestanding membranes. We show that using properly designed supports, in the form of microbeams, we can reduce the out-of-plane deflection of the membrane while maintaining its stiffness. As a proof of principle, we used a silicon-on-insulator (SOI) platform to fabricate 30 mu m wide, 220 nm thick, free-standing Si membranes, supported by four 15 mu m long and 3 mu m wide microbeams. Using our approach, we are able to achieve an out-of-plane deformation of the membrane smaller than 50 nm in spite of 39 MPa of compressive internal stress. Our method is general, and can be applied to different material systems with compressive or tensile internal stress.

    DOI

  • Towards optical manipulation of Casimir force using free-standing membranes with engineered optical and mechanical properties

    Eiji Iwase, Pui-Chuen Hui, David Woolf, Alejandro W. Rodriguez, Mughees Khan, Steven G. Johnson, Federico Capasso, Marko Loncar

    2012 CONFERENCE ON LASERS AND ELECTRO-OPTICS (CLEO)    2012  [Refereed]

     View Summary

    By engineering supporting beams of a thin opto-mechanical membrane, we are able to reduce the stress-induced deflection, and realize devices that feature strong optical force for probing the Casimir force.

  • Dynamics of a tethered silicon photonic crystal membrane due to optical gradient, photothermal and Casimir forces

    Pui-Chuen Hui, David Woolf, Eiji Iwase, Irfan Bulu, Alejandro Rodriguez, Mughees Khan, Parag Deotare, Steven G. Johnson, Federico Capasso, Marko Loncar

    2012 CONFERENCE ON LASERS AND ELECTRO-OPTICS (CLEO)    2012  [Refereed]

     View Summary

    We experimentally studied the effects of optical gradient and photothermal forces on the optomechanics of tethered silicon membranes. Novel engineering of support arms facilitates tunable optomechanical coupling and probing of Casimir interactions.

  • Designing evanescent optical interactions to control the expression of Casimir forces in optomechanical structures

    Alejandro W. Rodriguez, David Woolf, Pui-Chuen Hui, Eiji Iwase, Alexander P. McCauley, Federico Capasso, Marko Loncar, Steven G. Johnson

    APPLIED PHYSICS LETTERS   98 ( 19 ) 194105  2011.05  [Refereed]

     View Summary

    We propose an optomechanical structure consisting of a photonic-crystal (holey) membrane suspended above a layered silicon-on-insulator substrate in which resonant bonding/antibonding optical forces created by externally incident light from above enable all-optical control and actuation of stiction effects induced by the Casimir force. In this way, one can control how the Casimir force is expressed in the mechanical dynamics of the membrane, not by changing the Casimir force directly but by optically modifying the geometry and counteracting the mechanical spring constant to bring the system in or out of regimes where Casimir physics dominate. The same optical response (reflection spectrum) of the membrane to the incident light can be exploited to accurately measure the effects of the Casimir force on the equilibrium separation of the membrane. (C) 2011 American Institute of Physics. [doi:10.1063/1.3589119]

    DOI CiNii

  • Optical bonding and antibonding forces in asymmetric geometries for Casimir force detection

    David Woolf, Pui-Chuen Hui, Eiji Iwase, Alexajandro Rodriguez, Alexander McCauley, Igor Lovchinsky, Mughees Kahn, Steven Johnson, Marko Loncar, Federico Capasso

    2011 CONFERENCE ON LASERS AND ELECTRO-OPTICS (CLEO)    2011  [Refereed]

     View Summary

    The optical bonding (attractive) and antibonding (repulsive) forces between a suspended, holey Silicon membrane and a Silicon-on-Insulator (SOI) substrate are shown to offer a sensitive new method for plane-plane geometry Casimir force detection. (C) 2010 Optical Society of America

  • Bonding, antibonding and tunable optical forces in asymmetric membranes

    Alejandro W. Rodriguez, Alexander P. McCauley, Pui-Chuen Hui, David Woolf, Eiji Iwase, Federico Capasso, Marko Loncar, Steven G. Johnson

    OPTICS EXPRESS   19 ( 3 ) 2225 - 2241  2011.01  [Refereed]

     View Summary

    We demonstrate that tunable attractive (bonding) and repulsive (anti-bonding) forces can arise in highly asymmetric structures coupled to external radiation, a consequence of the bonding/anti-bonding level repulsion of guided-wave resonances that was first predicted in symmetric systems. Our focus is a geometry consisting of a photonic-crystal (holey) membrane suspended above an unpatterned layered substrate, supporting planar waveguide modes that can couple via the periodic modulation of the holey membrane. Asymmetric geometries have a clear advantage in ease of fabrication and experimental characterization compared to symmetric double-membrane structures. We show that the asymmetry can also lead to unusual behavior in the force magnitudes of a bonding/antibonding pair as the membrane separation changes, including nonmonotonic dependences on the separation. We propose a computational method that obtains the entire force spectrum via a single time-domain simulation, by Fourier-transforming the response to a short pulse and thereby obtaining the frequency-dependent stress tensor. We point out that by operating with two, instead of a single frequency, these evanescent forces can be exploited to tune the spring constant of the membrane without changing its equilibrium separation. (C) 2011 Optical Society of America

    DOI

  • Long-range surface plasmon resonance sensor with liquid micro-channels to maintain the symmetry condition of the refractive index

    Tetsuo Kan, Hiroyuki Kojo, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    JOURNAL OF MICROMECHANICS AND MICROENGINEERING   20 ( 12 ) 125005  2010.12  [Refereed]

     View Summary

    We propose a method to maintain the symmetry of the refractive index with respect to an Au film, in which the refractive indices are the same near both surfaces of the Au film, for LRSPR (long-range surface plasmon resonance) sensors. Maintenance of the symmetry is necessary for exciting the LRSPR mode. However, because the buffer layer under the Au film is usually made of a solid dielectric material with a constant refractive index, the quality of the measurement is reduced when the refractive index of the analyte used is dramatically different from that of the buffer layer. To solve this problem, the proposed sensor is equipped with liquid channels under the Au film. The Au film used in this study was supported by a thin (100 nm) polymer film forming parallel, one-dimensional liquid channels with a 29 mu m pitch. Because the analyte solution flows in the channels, both surfaces of the Au film face the same analyte. Thus, this configuration automatically satisfies the symmetry condition for analytes with a wide range of refractive indices. We examined the validity of the sensor and compared it to that of a conventional sensor by measuring the LRSPR for five analyte solutions with different refractive indices. LRSPR dips were clearly observed for all of the analytes tested. The dip of the conventional LRSPR sensor became shallow when the refractive index increased, with the final dip depth being 65% of the initial dip depth for a refractive index of 1.358. In contrast, the dip depth of the proposed LRSPR sensor remained constant over the entire measured refractive index range of 1.331 to 1.358. These results indicate that the proposed sensor maintains the symmetry condition and confirm that the proposed method is effective for highly sensitive LRSPR measurements for a wide variety of analyte species.

    DOI

  • Differential pressure measurement using a free-flying insect-like ornithopter with an MEMS sensor

    Hidetoshi Takahashi, Yuichiro Aoyama, Kazuharu Ohsawa, Hiroto Tanaka, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    BIOINSPIRATION & BIOMIMETICS   5 ( 3 ) 036005  2010.09  [Refereed]

     View Summary

    This paper presents direct measurements of the aerodynamic forces on the wing of a free-flying, insect-like ornithopter that was modeled on a hawk moth (Manduca sexta). A micro differential pressure sensor was fabricated with micro electro mechanical systems (MEMS) technology and attached to the wing of the ornithopter. The sensor chip was less than 0.1% of the wing area. The mass of the sensor chip was 2.0 mg, which was less than 1% of the wing mass. Thus, the sensor was both small and light in comparison with the wing, resulting in a measurement system that had a minimal impact on the aerodynamics of the wing. With this sensor, the 'pressure coefficient' of the ornithopter wing was measured during both steady airflow and actual free flight. The maximum pressure coefficient observed for steady airflow conditions was 1.4 at an angle of attack of 30 degrees. In flapping flight, the coefficient was around 2.0 for angles of attack that ranged from 25 degrees to 40 degrees. Therefore, a larger aerodynamic force was generated during the downstroke in free flight compared to steady airflow conditions.

    DOI

  • Transparent conductive-polymer strain sensors for touch input sheets of flexible displays

    Seiichi Takamatsu, Tomoyuki Takahata, Masato Muraki, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    JOURNAL OF MICROMECHANICS AND MICROENGINEERING   20 ( 7 ) 075017  2010.07  [Refereed]

     View Summary

    A transparent conductive polymer-based strain-sensor array, designed especially for touch input sheets of flexible displays, was developed. A transparent conductive polymer, namely poly(3, 4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS), was utilized owing to its strength under repeated mechanical bending. PEDOT: PSS strain sensors with a thickness of 130 nm exhibited light transmittance of 92%, which is the same as the transmittance of ITO electrodes widely used in flat panel displays. We demonstrated that the sensor array on a flexible sheet was able to sustain mechanical bending 300 times at a bending radius of 5 mm. The strain sensor shows a gauge factor of 5.2. The touch point on a flexible sheet could be detected from histograms of the outputs of the strain sensors when the sheet was pushed with an input force of 5 N. The touch input could be detected on the flexible sheet with a curved surface (radius of curvature of 20 mm). These results show that the developed transparent conductive polymer-based strain-sensor array is applicable to touch input sheets of mechanically bendable displays.

    DOI

  • Three-dimensional silicon fabrication using microloading effects with a rectangular aperture mask

    Tomoyuki Takahata, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    JOURNAL OF MICROMECHANICS AND MICROENGINEERING   20 ( 7 ) 075022  2010.07  [Refereed]

     View Summary

    Three-dimensional silicon fabrication is demanded in optical lenses for collecting far infrared radiation. We propose a method for the fabrication of shapes, which have depths varying in the x and y directions, vertical walls and smooth surfaces. A mask design with rectangular apertures was used in a two-stage etching process consisting of anisotropic etching to rough out the three-dimensional shape followed by isotropic etching to smooth the surface. The relationship between the etching depth and area and the aspect ratio (length-to-height ratio) of the rectangular apertures was determined experimentally. Based on this relationship, we describe a procedure for designing rectangular apertures. We fabricated a convex microlens with a diameter of 150 mu m and a height of 4.3 mu m surrounded by a vertical wall. The arithmetic mean surface roughness of the microlens was 100 nm.

    DOI

  • Fabrication and demonstration of an electrochromic voxel array for a volume display prototype

    Seiichi Takamatsu, Sachio Murao, Nguyen Binh-Khiem, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    IEICE ELECTRONICS EXPRESS   7 ( 13 ) 920 - 924  2010.07  [Refereed]

     View Summary

    We fabricated and demonstrated electrochromic voxel arrays for a three-dimensional (3D) display prototype. A voxel is a cubic display element of a 3D image. The voxels were constructed with ultraviolet-curable polymer on a substrate with a MEMS process and coated with poly-(3,4-ethylenedioxythiophene): poly-styrenesulfonate (PEDOT:PSS). The resultant substrates were stacked in three-dimensional space. The PEDOT: PSS color changes from transparent to blue when -1V is applied. The coloration of one voxel was observed from the top and side views, and the coloration of a 3 x 3 x 3 voxel array was also observed.

    DOI CiNii

  • Liquid-Phase Packaging of a Glucose Oxidase Solution with Parylene Direct Encapsulation and an Ultraviolet Curing Adhesive Cover for Glucose Sensors

    Seiichi Takamatsu, Hisanori Takano, Nguyen Binh-Khiem, Tomoyuki Takahata, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    SENSORS   10 ( 6 ) 5888 - 5898  2010.06  [Refereed]

     View Summary

    We have developed a package for disposable glucose sensor chips using Parylene encapsulation of a glucose oxidase solution in the liquid phase and a cover structure made of an ultraviolet (UV) curable adhesive. Parylene was directly deposited onto a small volume (1 mu L) of glucose oxidase solution through chemical vapor deposition. The cover and reaction chamber were constructed on Parylene film using a UV-curable adhesive and photolithography. The package was processed at room temperature to avoid denaturation of the glucose oxidase. The glucose oxidase solution was encapsulated and unsealed. Glucose sensing was demonstrated using standard amperometric detection at glucose concentrations between 0.1 and 100 mM, which covers the glucose concentration range of diabetic patients. Our proposed Parylene encapsulation and UV-adhesive cover form a liquid phase glucose-oxidase package that has the advantages of room temperature processing and direct liquid encapsulation of a small volume solution without use of conventional solidifying chemicals.

    DOI

  • FORCE SENSOR BASED ON METAL NANOPARTICLE

    Asuto Koyama, Tetsuo Kan, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    MEMS 2010: 23RD IEEE INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS, TECHNICAL DIGEST     428 - 431  2010  [Refereed]

     View Summary

    We propose a force sensor based on gold nanoparticles, which enable optical detection of force by measurement of the scattering light spectrum. Gold nanoparticles were dispersed on an elastomer sheet. The scattering spectrum changes due to strain were observed to investigate applicability of the sensor to force measurement. The force deforms the elastomer sensor body, and increases the interparticle distance of gold nanoparticles on the sheet. The increase of the interparticle distance gives rise to the scattering characteristic changes. We fabricated a prototype sensor using PDMS sheet and 40 nm of diameter gold nanoparticles. It was demonstrated that 21% strain induced 60% increase of scattering intensity of gold nanoparticles.

  • TRIAXIAL FORCE MEASUREMENT CANTILEVER BY SIDEWALL-DOPING WITH RAPID THERMAL DIFFUSION

    Yuichiro Aoyama, Nguyen Binh-Khiem, Kentaro Noda, Yusuke Takei, Tetsuo Kan, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    MEMS 2010: 23RD IEEE INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS, TECHNICAL DIGEST     619 - 622  2010  [Refereed]

     View Summary

    We propose a triaxial force measurement cantilever with piezoresistors fabricated by rapid thermal diffusion sidewall-doping. The device is developed as a tool for applying quantitative mechanical stimuli to cells and measuring their mechanical properties at the same time. The device consists of a sensing tip, two sensing beams, and four wiring beams. We form piezoresistors on the surface of the sensing tip and the sidewalls of the two sensing beams. We confirmed that our device was able to measure triaxial forces. The displacement sensitivities of the device were 1.59x10(-3) mu m(-1), 1.18x10(-3) mu m(-1) and 3.26x10(-4) mu m(-1) for x, y, and z-direction, respectively.

    DOI

  • SOUND DIRECTION SENSOR WITH AN ACOUSTIC CHANNEL

    Minh Dung Nguyen, Akira Inaba, Akira Suzuki, Hidetoshi Takahashi, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    MEMS 2010: 23RD IEEE INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS, TECHNICAL DIGEST     655 - 658  2010  [Refereed]

     View Summary

    This paper reports on a method for estimating direction of a sound with one directional acoustic sensor. Inspired by the two input structure of bushcricket ear, our sensor was designed to have an acoustic channel and a micro piezo-resistive cantilever. The radiated sound acts simultaneously on the external and on the inner surface of the cantilever. As the result, the directionality of our sensor varies with the frequency of incident sound. The sound direction was estimated by using directional responses of the sensor at multiple frequencies so that it does not require either angle scanning or microphone arrays. We demonstrated that this method enables the sound direction to be estimated with the average error of 4 degrees in laboratory experiments.

  • PHOTO-RESPONSE COMPENSATED PIEZORESISTIVE CANTILEVER FOR USE IN FLUORESCENCE MICROSCOPY

    Uijin Jung, Kenta Kuwana, Hidetoshi Takahashi, Tetsuo Kan, Yusuke Takei, Kentaro Noda, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    MEMS 2010: 23RD IEEE INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS, TECHNICAL DIGEST     588 - 591  2010  [Refereed]

     View Summary

    This paper presents the design, fabrication, and the characterization of a photo-response compensated piezoresistive cantilever. The application field of the cantilever is to measure cellular mechanical properties under fluorescence microscopy. Photo-response which is caused by an excitation light of a fluorescence microscope interferes with measurement. We proposed piezoresistive cantilevers consist of a force-sensing cantilever with a reference cantilever to cancel out the photo-response. We measured the photo-response of the fabricated device, by varying wavelength, light intensity and light incidence angle. The experimental results show that the photo-response was decreased by 87%. This verified that present device has effective photo-response compensation by using the reference cantilever.

    DOI

  • MEASUREMENT OF THE IMPACT STRESS IN A GOLF CLUB HEAD

    Akira Hasegawa, Akihito Nakai, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    MEMS 2010: 23RD IEEE INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS, TECHNICAL DIGEST     592 - 595  2010  [Refereed]

     View Summary

    We directly measured the stresses induced on impact between a golf ball and a golf club head. The strain sensors were embedded into grooves on the face of the club head. 3-axis strain sensors were able to measure one normal stress and two shear stresses at each location. The shear stress directions indicated by the outputs of the sensors were in good agreement with the direction of the ball spin obtained from high speed camera images. The peak of the normal stress and shear stress on the contact face were measured to be 4x10(8) Pa and 1x10(8) Pa, respectively.

  • THERMAL-BASED SKIN MOISTURE DEVICE WITH CONTACT PRESSURE SENSOR

    K. Katoh, Y. Ichikawa, E. Iwase, K. Matsumoto, I. Shimoyama

    MEMS 2010: 23RD IEEE INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS, TECHNICAL DIGEST     276 - 279  2010  [Refereed]

     View Summary

    This paper reports on a thermal-based device for measuring water content in human skin. The device consists of resistive temperature detectors (RTD) and a pressure sensor. The RTD was also used as a heat source, and the pressure sensor was used to obtain constant thermal contact. Water content was measured by heat extraction rate across device interface under constant contact pressure. The device detected difference in water content of a contact object from 0.02 to 0.56g/cm(3) by measuring step response of the RTD in 3 seconds. Difference in water content of the human skin was actually detectable with the device in 3 seconds.

  • Stretchable liquid tactile sensor for robot-joints

    K. Noda, E. Iwase, K. Matsumoto, I. Shimoyama

    2010 IEEE INTERNATIONAL CONFERENCE ON ROBOTICS AND AUTOMATION (ICRA)     4212 - 4217  2010  [Refereed]

     View Summary

    In this paper, we propose a stretchable tactile sensor composed of a pair of silicone rubber channels filled with electro conductive liquid. When a force was applied to this channel, its length and cross-sectional area deforms. By measuring the resistance change of the electro conductive liquid in the channel, its deformation can be measured. The proposed tactile sensor is composed of two parallel channel filled with electro conductive liquid, therefore, by comparing the resistance changes of each channel to the deformation, only the contacting force can be measured independently. Since a liquid is used for the sensing material, the proposed liquid tactile sensor can be easily attached to movable portions as the joints of robots.
    In the paper, we measured the sensing characteristics of the liquid tactile sensor to the stretch, bend, and contact force. Finally, the efficiency of the sensor was demonstrated by measuring the contact force from 0 to 3.0N by attaching the 20% stretched liquid tactile sensor to curved surfaces with 0.05mm(-1) in curvature.

    DOI

  • Planar near-infrared surface plasmon resonance sensor with Si prism and grating coupler

    Tetsuo Kan, Naoko Tsujiuchi, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    SENSORS AND ACTUATORS B-CHEMICAL   144 ( 1 ) 295 - 300  2010.01  [Refereed]

     View Summary

    We have developed a silicon-microfabrication-based surface plasmon resonance (SPR) sensor with Si prisms and an optical grating. Since this sensor is compatible with microelectromechanical systems technology. it can be further miniaturized and integrated with optical parts or fluidic components for the realization of a one-chip SPR sensor. The Si prism structure, transparent in the near-infrared range, was used to lead the 1550-nm measuring light to the sensing Surface where the evanescent light was generated. Smooth prism slopes were obtained by using anisotropic etching to Utilize the (1 1 1) planes on the (1 0 0) Surface plane of single-crystalline Si wafer. The result Was a 200-mu m-pitch array of prisms with 54.74 slope angles. In this configuration the range of incident angles at which near-infrared light produces an SPR dip is from 38.26 degrees to 71.24 degrees. Because the SPR angles for major specimens (16.60 degrees for air. 22.06 degrees for water, and 22.79 degrees for ethanol) are Out of range, we used an optical grating with a roughly 400-nm-pitch to make an SPR clip position move to fit within the available angle range by the diffraction effect. SPR measurements with several specimens confirmed that the combination of Si prisms and the optical grating excited Surface plasmons. The measured SPR dip positions and their sensitivity to refractive index were compared with the theoretical values, and their consistency confirmed the utility of this device as an SPR sensor. (C) 2009 Elsevier B.V. All rights reserved.

    DOI CiNii

  • Fabrication of three dimensional silicon slopes using mask With square openings

    Yusuke Takei, Takahiro Ohori, Tomoyuki Takahata, Tetsuo Kan, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    IEEJ Transactions on Sensors and Micromachines   130 ( 5 ) 6 - 187  2010  [Refereed]

     View Summary

    We propose a fabrication method of three-dimensional silicon slopes using RIE-lag. RIE-lag is a lag of an etching rate depending on square openings area of a mask. We measured relationship between area of square openings and etched depths. We confirmed that etched depths were defined as a function of the square openings. With this relationship, we designed a mask with various sizes of the squares for slope structures. Square openings of various sizes were patterned using EB lithography. Silicon was etched vertically with ICP-RIE (Inductive Coupled Plasma - Reactive Ion Etching). By RIE-lag, trenches with multiple depths depending on the area of the square openings were formed. Silicon surface was smoothed by SF6 isotropic dry etching. As a result, by the combination of ICP-RIE anisotropic etching RIE-lag and SF6 isotropic etching, we fabricated 57° silicon slopes of surface roughness 10 nm in plane and 35 nm in slope surface. © 2010 The Institute of Electrical Engineers of Japan.

    DOI CiNii

  • Self-alignment method on a temperature-controlled transfer

    Eiji Iwase, Hiroaki Onoe, Akihito Nakai, Kiyoshi Matsumoto, Isao Shimoyama

    IEEJ Transactions on Sensors and Micromachines   130 ( 5 ) 7 - 193  2010  [Refereed]

     View Summary

    We propose a method to fix the positioning error of transferred bare chips on a substrate after the Temperature-Controlled Transfer (TCT) that we have previously developed. This TCT method is important for large area integration of heterogeneous materials. In the TCT process, the bare chips on an adhesive sheet are transferred and electrically connected to the substrate via Low-Melting Point Solder (LMPS). We reflowed the LMPS and used the surface tension of the LMPS to self-align the bare chips in position on the substrate. We experimentally confirmed that the self-alignment works when contact pads on the bare chip and the substrate were overlapped. The positioning error after the self-alignment process was within 0-15 % of the contact pad size. © 2010 The Institute of Electrical Engineers of Japan.

    DOI CiNii

  • Differential Pressure Measurement on Insect Modeled Ornithopter with MEMS Sensor in Free-Flight

    大澤一治, 青山雄一郎, 高橋英俊, 田中博人, 岩瀬英治, 松本潔, 下山勲

    日本ロボット学会誌   28 ( 9 ) 1131 - 1136  2010  [Refereed]

     View Summary

    To achieve flight, an insect generates aerodynamic force by flapping its wings. However, this aerodynamic force acting on the wings has not been directly measured during free-flight. In this study, we fabricated an ornithopter modeled on a hawk moth, and attached a MEMS differential pressure sensor on its wing. Then, we measured differential pressure between upper and lower surfaces of the wing during free-flight. Reynolds number of the wing and wing load of the ornithopter were designed to be 4.2 × 103[–], and 7.5[N/m2], which were close to those of a hawk moth. The mass, wing length and flapping frequency were 6.8[g], 110[mm] and 13[Hz], respectively. The maximum differential pressures at the center of the wing were 39[Pa] and 18[Pa] during downstroke and upstroke, which were 5 and 2 times larger than the wing load. The differential pressure contributed vertical pressure of 38[Pa] during downstroke and horizontal pressure of 15[Pa] during upstroke. The time average of vertical differential pressure was 7.0[Pa], which was as large as the wing load of the ornithopter.

    DOI CiNii

  • Encapsulation method of glucose oxidase solution with ionic liquid solvent and direct parylene deposition

    Seiichi Takamatsu, Hisanori Takano, Nguyen Binh-Khiem, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    IEEJ Transactions on Sensors and Micromachines   130 ( 12 ) 1 - 569  2010  [Refereed]

     View Summary

    We developed new encapsulation method of glucose oxidase solution with ionic liquid solvent and direct Parylene deposition for the application to MEMS glucose sensors. Glucose oxidase has been immobilized in gel or polymer on MEMS sensors, but its weak mechanical property has been remained to be solved. Then, its encapsulation has been demanded, but high-temperature MEMS bonding process (&gt
    150*deg
    C) for packaging the solution is destructive to glucose oxidase which is denatured over 50 °C. To solve these problems, we encapsulated the glucose oxidase-ionic liquid solution with room-temperature packaging (25 °C) of direct Parylene deposition process. The glucose oxidase solution array with the area of 1 ×3) mm2 (approximately 1 μl) was patterned on the hydrophilic-hydrophobic surface modification on the MEMS electrochemical electrodes in the use of the wetting phenomenon of the solution and, then, packaged by the chemical vapor deposition of 1.5 μm Parylene. Parylene packages could be opened by pushing when used. The opened glucose oxidase solution reacted to 150 mM glucose solution, revealing the electrochemical potential of 150 mV. The sensitivity of our sensor ranged from 1 to 100 mM, which is the glucose concentration in the blood of the diabetic patients. Therefore, proposed encapsulation method exhibits the potential application to glucose sensor packages for diabetic patients. © 2010 The Institute of Electrical Engineers of Japan.

    DOI CiNii

  • Temperature-controlled transfer and self-wiring for multi-color light-emitting diode arrays

    Onoe, Hiroaki, Nakai, Akihito, Iwase, Eiji, Matsumoto, Kiyoshi, Shimoyama, Isao

    JOURNAL OF MICROMECHANICS AND MICROENGINEERING   19 ( 7 )  2009.07  [Refereed]

    DOI

  • Temperature-Controlled Transfer and Self-Wiring for Multi-Color LED Arrays

    Hiroaki Onoe, Akihito Nakai, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama, equal contribution

    Journal of Micromechanics and Microengineering   19 ( 7 ) 075015 - 1542  2009.07  [Refereed]

    DOI CiNii

  • Ellipsoidal micro lens fabricated by depositing parylene directly on liquid

    Ryoh Miyamoto, N. Binh-Khiem, E. Iwase, K. Matsumoto, I. Shimoyama

    TRANSDUCERS 2009 - 15th International Conference on Solid-State Sensors, Actuators and Microsystems     1365 - 1368  2009  [Refereed]

     View Summary

    We report on an ellipsoidal liquid lens fabricated by PoLD (Parylene on liquid deposition). We fabricated ellipsoidal liquid lenses of 0.50, 1.00, 1.50, and 2.00 μl in volume on hydrophilic elliptical domains with 5.00mm major diameter and 2.50mm minor diameter. We measured the two focal lengths corresponding to major and minor diameters by observing the image formed by a laser beam. We verified that measured focal lengths agreed with theoretical calculated results. In addition, we showed that our method enables us to fabricate ellipsoidal lenses which have the focal lengths as designed. ©2009 IEEE.

    DOI

  • Material discrimination by heat flow sensing

    K. Katoh, Y. Ichikawa, E. Iwase, K. Matsumoto, I. Shimoyama

    TRANSDUCERS 2009 - 15th International Conference on Solid-State Sensors, Actuators and Microsystems     1549 - 1552  2009  [Refereed]

     View Summary

    We propose a heat flow sensing device with a heat source to discriminate a contact object. The device was a three-layered structure separated by 600μm-thick PDMS (Polydimethylsiloxane) spacer, and consisted of a micro heater and three resistance-temperature detectors (RTD). We detected transient heat flow with pulse-heating method when 10mm-cubic blocks of cork, acrylic and aluminum were on contact with the device. Temperature gradient induced by heat flow differed by materials of contact objects. We also evaluated the surface temperature from two RTDs. Our device identified relative difference in thermal effusivity of materials. ©2009 IEEE.

    DOI

  • Self-aligned opposite mirrors for tilting field of view driven by electrowetting

    K. Suzuki, A. Takei, E. Iwase, K. Matsumoto, I. Shimoyama

    TRANSDUCERS 2009 - 15th International Conference on Solid-State Sensors, Actuators and Microsystems     2322 - 2325  2009  [Refereed]

     View Summary

    We propose an optical device which appends pan/tilt functions to cameras by moving mirrors with electrowetting force. The device is composed of two plates and a liquid pillar holding two mirrors. On the lower plate, electrodes are patterned and a hydrophobic layer is coated. When a voltage is applied to the electrode on the lower plate, the liquid is moved toward the electrode by electrowetting force. Consequently, the mirror is tilted and the light path that comes into the device is controlled. When a camera was put below our device, the field of view of the camera was shifted by 25 degrees with 50 V applied. ©2009 IEEE.

    DOI

  • Peristaltic micropump fabricated by depositing parylene directly on liquid

    Satoshi Komatsu, Nguyen Binh-Khiem, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    TRANSDUCERS 2009 - 15th International Conference on Solid-State Sensors, Actuators and Microsystems     2007 - 2010  2009  [Refereed]

     View Summary

    We fabricated a peristaltic micropump by depositing Parylene on liquid directly (PoLD method), and tested its pumping characteristics. The Parylene thin film deposited on liquid not only forms the membrane of the micropump, but also composes the whole structure of the microfluidic system. The pumping membrane can be deformed by electrostatic force. This deformation can create liquid flow. Our micropump can transfer liquid at the flow rate of 2.7μl/min and generate a differential pressure of 41Pa. On the other hand, this pump made a wrinkle when the voltage applied and it leaked liquid. We devised the shape of the channel and electrodes and enabled it to close tightly. ©2009 IEEE.

    DOI

  • Adhesion force mesurement between silicon and carbon nanotubes synthesized by chemical vapor deposition

    A. Hashimoto, Y. Takei, E. Iwase, K. Matsumoto, I. Shimoyama

    TRANSDUCERS 2009 - 15th International Conference on Solid-State Sensors, Actuators and Microsystems     2066 - 2069  2009  [Refereed]

     View Summary

    This paper reports on an evaluation of the adhesion force between silicon and carbon nanotubes (CNTs), which were directly synthesized on a silicon substrate by chemical vapor deposition (CVD). CNTs bridging between silicon tips were pushed with a force-sensing cantilever to break the adhesion between silicon and CNTs. We measured the force acting on the cantilever at the moment of breaking the adhesion between silicon and CNTs. This force was measured to be 28 nN. ©2009 IEEE.

    DOI

  • Sensitivity enhancement by micro helmholtz resonator for ultrasonic distance sensor

    A. Suzuki, H. Takahashi, E. Iwase, K. Matsumoto, I. Shimoyama

    TRANSDUCERS 2009 - 15th International Conference on Solid-State Sensors, Actuators and Microsystems     1557 - 1560  2009  [Refereed]

     View Summary

    This paper reports on a micro Helmholtz resonator (HR) enhancing the sensitivity of an ultrasonic distance sensor. Attaching an HR to the sensor that consists of a piezoresistive cantilever microphone makes its sensitivity against ultrasonic wave higher. A HR of 600 μm height demonstrated a 17.5 times larger maximum amplitude of the cantilever vibration against single frequency wave. We also evaluated the dependence of the sensitivity on frequency and acoustic pressure. Our sensor was able to detect the distance of 0.5-6.0 m with the maximum error of 2.0%. ©2009 IEEE.

    DOI

  • Micro liquid prism

    Y. Yoshihata, A. Takei, N. Binh Khiem, T. Kan, E. Iwase

    Proceedings of the IEEE International Conference on Micro Electro Mechanical Systems (MEMS)     967 - 970  2009  [Refereed]

     View Summary

    This paper presents a micro liquid prism. Two flat transparent plates float on a liquid droplet and these plates serve as prism faces. The two plates are positioned automatically by surface tension, just by putting the plates on the ellipsoidal droplet. Therefore the proposed prism can be fabricated accurately in micro scale without difficulty. As the liquid and the plates are encapsulated by Parylene, the prism can retain its shape. The prism which faces were 400ptm in diameter and whole size was smaller than 1mm3 was fabricated. The adequate function of the fabricated prism for Surface Plasmon Resonance (SPR) measurement was verified. ©2009 IEEE.

    DOI

  • Solution electrochemiluminescent microfluidic cell for flexible and stretchable display

    R. Okumura, S. Takamatsu, E. Iwase, K. Matsumoto, I. Shimoyama

    Proceedings of the IEEE International Conference on Micro Electro Mechanical Systems (MEMS)     947 - 950  2009  [Refereed]

     View Summary

    We developed liquid luminescent flexible displays using electrochemiluminescent solution as deformable luminescent material. The solution consisted of ruthenium complexes as light emitting material and ionic liquid as nonvolatile solvent. We injected the solution, to pattern and seal it, into microfluidic cells between two flexible films of polyethylene terephthalate substrates with indium tin oxide electrodes. The light emitting area of one cell was 2×2 mm2 The gap between the electrodes was 100 μm. We measured the luminance of the cell during application of 5OHz/4.OVpp (peak-to-peak value) rectangular waves of voltage in bent condition. The device was bent along the convex curvature with radii of 60, 30 and 20 mm. The luminance was reduced by only 30 00 when the radius of curvature reached 20 mm. We conclude the electrochemiluminescent cells are suitable for flexible displays because they can tolerate large deformation of bending. ©2009 IEEE.

    DOI

  • Stretchable substrates for the measurement of intracellular calcium ion concentration responding to mechanical stress

    Y. J. Heo, E. Iwase, K. Matsumoto, I. Shimoyama

    Proceedings of the IEEE International Conference on Micro Electro Mechanical Systems (MEMS)     68 - 71  2009  [Refereed]

     View Summary

    This paper presents the design, fabrication, and the characterization of a stretchable substrate, achieving the change of intracellular calcium ion concentration by mechanical stress. We propose the stretchable substrate integrated with the air chambers of the pneumatic actuator. We have measured the areal strain depending on input pressure and the intracellular calcium ion concentration increase in response to the mechanical stress. The present stretchable substrate is able to provide the areal strain of 5.21%~12.3% for the input pressure of 34.5kPa~103kPa. We also verified that the present stretchable substrate is able to stimulate cells by the mechanical stress applied through integrins, showing potential feasible application for monitoring the calcium ion influx caused by the mechanical stress. ©2000 IEEE.

    DOI

  • INTEGRATION OF BRIDGING-STRUCTURAL SWNTS ON FLEXIBLE PDMS SHEET BY STAMPING TRANSFER

    Yusuke Takei, Tetsuo Kan, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    IEEE 22ND INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS (MEMS 2009)     551 - 554  2009  [Refereed]

     View Summary

    This paper describes an integration method of bridging-structural single-walled carbon nanotubes (SWNTs) onto the flexible PDMS sheet by stamping transfer. Silicon microstructures and the SWNTs which directly synthesized between the gaps of the microstructures were lifted off by PDMS stamp sheets with high yield (97.8 %) and accuracy (position error &lt; 100 nm). From the SEM observation of our transferred structures, we confirmed that our method could transfer the bridging-structural SWNTs on to the flexible materials without any damage to the SWNTs' bridging.
    [GRAPHICS]
    .

    DOI

  • TEMPERATURE-CONTROLLED TRANSFER AND SELF-WIRING FOR MULTI-COLOR LED DISPLAY ON A FLEXIBLE SUBSTRATE

    Eiji Iwase, Hiroaki Onoe, Akihito Nakai, Kiyoshi Matsumoto, Isao Shimoyama

    IEEE 22ND INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS (MEMS 2009)     176 - 179  2009  [Refereed]

     View Summary

    We propose an integration method for arranging LED bare chips on a flexible substrate to fabricate a multi-color LED display. LED chips (240 mu m x 240 mu m x 75 mu m) which were arrayed on an adhesive sheet were transferred to a flexible circuit substrate using our temperature-controlled transfer (TCT) and self-wiring (SW) method. Using these methods, we demonstrated a 5-by-5 LED flexible device and a two-color (blue and green) LED device, and observed light emission from the LED chips.

  • Air flow senser for an insect-like flapping wing

    Hidetoshi Takahashi, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the IEEE International Conference on Micro Electro Mechanical Systems (MEMS)     916 - 919  2008  [Refereed]

     View Summary

    This paper reports on a thin piezoresistive cantilever for measuring air flow velocity around flapping wings. To measure the air flow velocity at a point of the wing directly, our sensor was attached to the leading edge of the wing. The sensor was designed to be 1 ?m thick. Because of the scale effect, the influence of the inertial force was small during flow measurement. The sensor had the sensitivity of 0.56 - 0.96 × 10-3 (m/s)-2 as well as the directivity. By using the micro flow sensor, we measured the perpendicular air flow velocity at the point of the leading edge of the wing. ©2008 IEEE.

    DOI

  • Liquid motor driven by electrowetting

    A. Takei, N. Binh-Khiem, E. Iwase, K. Matsumoto, I. Shimoyama

    MEMS 2008: 21ST IEEE INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS, TECHNICAL DIGEST     42 - 45  2008  [Refereed]

     View Summary

    We propose a liquid motor using surface tension. Our liquid motor is composed of a liquid droplet floating plate and a lower plate. The plate floating on thee droplet is rotated continuously by electrowetting actuation. The floating plate is asymmetrically and has four cogs. By electrowetting actuation, the shape of the droplet is deformed. Then, the floating plate rotates to the position where the surface energy of the sandwiched liquid takes a minimum value. On the lower plate, electrodes are patterned in an annular shape. By choosing the voltage-applied electrodes, the position of the floating plate is controlled. In this research, a 2 mm floating plate with a 500 mu m silicon cube was rotated at 180 rpm. This motor is useful for optical devices because the components of the liquid motor can be made of transparent materials.

  • Scanning micromirror using deformation of a parylene-encapsulated liquid structure

    Yuta Yoshihata, Nguyen Binh-Khiem, Atsushi Takei, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    MEMS 2008: 21ST IEEE INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS, TECHNICAL DIGEST     770 - 773  2008  [Refereed]

     View Summary

    This paper presents a scanning micromirror using deformation of a Parylene-Encapsulated Liquid Structure (PELS). Silicone fluid is put between a silicon plate and an electrode-patterned plate. Both of the plates and liquid are encapsulated by a Parylene membrane. Gold is deposited on the surface of the Parylene membrane to fabricate an upper electrode. By applying voltage between the upper and lower electrodes, the encapsulated liquid is deformed and the silicon plate is tilted. The silicon plate is supported by the PELS, instead of usual torsion beams. When a set of four appropriately synchronized voltages is applied between the four lower electrodes and the upper electrode, two dimensional scanning motion is achieved.

  • Hidden vertical comb-drive actuator on PDMS fabricated by parts-transfer

    Eiji Iwase, Hiroaki Onoe, Kiyoshi Matsumoto, Isao Shimoyama

    MEMS 2008: 21ST IEEE INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS, TECHNICAL DIGEST     116 - 119  2008  [Refereed]

     View Summary

    This paper reports complex three-dimensional (3-D) MEMS devices (polydimethylsiloxane) fabricated on PDMS by a parts-transfer method. Our target size of parts is 100-mu m-order in our parts-transfer method. First, we evaluate the transfer yield and the positioning accuracy. Secondly, we assemble a hidden vertical comb-drive actuator, including comb-electrodes and a support beam underneath its upper plate. Finally, we measure the drive characteristics of the actuator. Our actuators are the first demonstration of fabricating movable MEMS devices by parts-transfer technique. The demonstration indicates that complex 3-D MEMS devices with movable mechanical functions can be fabricated simply using our method.

  • Batch fabrication of carbon nanotubes at AFM probe tips and AFM imaging

    Kazuhiko Takagahara, Yusuke Takei, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    MEMS 2008: 21ST IEEE INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS, TECHNICAL DIGEST     713 - 716  2008  [Refereed]

     View Summary

    We synthesized carbon nanotubes (CNTs) at the tips of commercial atomic force microscope (AFM) probes by chemical vapor deposition (CVD) process with applying an electric field. Applying the electric field during the CVD process increased the yield of AFM probes with CNTs at the tips (CNT-AFM probes). We formed a catalyst layer on the surface of AFM probes, and carried out the CVD process to synthesize CNTs. After the CVD process, we observed the tips of the AFM probes with a scanning electron microscope (SEM). The yield of CNT-AFM probes was about 52 %. The CNTs were determined by resonance Raman spectroscopy using a 488 nm argon ion laser. Observed Raman peaks were peculiar to single-walled carbon nanotubes (SWNTs). Then we obtained AFM images of a sample grating with the CNT-AFM probes. The CNT-AFM probes had higher horizontal resolution than standard commercial AFM probes.

  • Tapered waveguide by liquid for a coupler of optical fibers to MEMS devices

    Hisashi Terae, Binh-Khiem Nguyen, Tomoyuki Takahata, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    MEMS 2008: 21ST IEEE INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS, TECHNICAL DIGEST     794 - 797  2008  [Refereed]

     View Summary

    We report a tapered liquid waveguide for an optical fiber-to-chip coupler. The tapered liquid waveguide has a smooth surface and has both a large structure and a micro structure on one chip. The waveguide is able to couple optical fibers of large-diameter to small MEMS devices. A Parylene film on the liquid prevented the liquid from deformation and evaporation. We fabricated the silicone oil waveguide by hydrophobicity of CYTOP. We measured a propagation loss of the tapered waveguide by entering the laser beam from the incident face. From a measurement result, this tapered waveguide can be a coupler which connects optical fibers to MEMS devices.

    DOI

  • Angle-tunable liquid wedge prism driven by electrowetting

    Atsushi Takei, Eiji Iwase, Kazunori Hoshino, Kiyoshi Matsumoto, Isao Shimoyama

    JOURNAL OF MICROELECTROMECHANICAL SYSTEMS   16 ( 6 ) 1537 - 1542  2007.12  [Refereed]

     View Summary

    We developed a tunable wedge prism by electrowetting actuation. Our prism can shift the field of view to the left or to the right and is useful for small cameras and endoscopes because its field of view can be changed without the need for large instruments. It consists of two plates that face each other, and a liquid is sandwiched between them. The liquid and plates form a wedge when the angle between the plates is changed. We used electrowetting to change the angle between the plates. The wedge prism is small because the liquid driven by electrowetting works as a prism. In addition, the prism produces a clear field of view because its optical flatness is determined by the flatness of the plates.

    DOI

  • Three-dimensional integration of heterogeneous silicon micro-structures by liftoff and stamping transfer

    Hiroaki Onoe, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    JOURNAL OF MICROMECHANICS AND MICROENGINEERING   17 ( 9 ) 1818 - 1827  2007.09  [Refereed]

     View Summary

    We propose a method of integrating heterogeneous silicon microstructures ( typical scale of 10-100 mu m) into a single silicon substrate to fabricate MEMS structures. It includes adhesion-based liftoff and stamping transfer ( LIST) processes using poly-(dimethylsiloxane) ( PDMS) sheets. Silicon microstructures fabricated on different wafers are lifted onto the PDMS sheets by breaking the narrow columns supporting the microstructures by applying a vertical load to the PDMS sheet, and then transferred onto the silicon substrate with high yield ( more than 90%) and superior positioning accuracy ( within 0.3 mu m on average in a 2 x 3 mm area). Multiple heterogeneous silicon structures are integrated into a single silicon substrate by repeating this LIST process. We fabricated two-dimensional arrays, three-dimensional pyramidal structures and overhanging bridge microstructures with our method, which proved that the LIST process could be used to integrate heterogeneous MEMS structures into a single wafer.

    DOI CiNii

  • 3D integration of heterogeneous MEMS structures by stamping transfer

    Hiroaki Onoe, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    PROCEEDINGS OF THE IEEE TWENTIETH ANNUAL INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS, VOLS 1 AND 2     366 - 369  2007  [Refereed]

     View Summary

    We propose an integration method of heterogeneous micro-electro-mechanical-system (MEMS) structures by liftoff and stamping transfer using a poly-(dimethylsiloxane) (PDMS) sheet. Silicon structures fabricated on multiple wafers were lifted off by PDMS sheets, and integrated onto a single wafer by the stamping transfer with high yield (&gt; 90%) and high accuracy (position error &lt; 500 nm). A two-dimensional (2D) integration and three-dimensional (3D) assembly of pyramid-like/inverted pyramid-like structures were demonstrated by our method. These demonstrations prove that our method enables us to integrate process-incompatible heterogeneous MEMS structures onto a single wafer.

  • Electrically driven varifocal micro lens fabricated by depositing parylene directly on liquid

    Binh-Khiem Nguyen, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    PROCEEDINGS OF THE IEEE TWENTIETH ANNUAL INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS, VOLS 1 AND 2     398 - 401  2007  [Refereed]

     View Summary

    The design and fabrication process of an electrically-driven varifocal liquid microlens are reported with experimental measurement results and a theoretical calculation model. Droplets of oil are sandwitched between a glass wafer and a thin-film of parylene chemical vapor deposited (CVD) directly onto the droplets' liquid surface. A method for creating fluid-filled micro chambers was realized with two core steps: 1) placing-shaping of oil droplets with hydrophobic/hydrophilic patterns and 2) coating them with a thin CVD parylene film in high vacuum condition. Liquid lenses and lens arrays of diameter from 20 mu m to 10mm were fabricated. In the tuning experiment, focal length was shortened to 20% of its initial value, from 3.8mm to 0.8mm. The values calculated from model match the data collected from experiments within the range of applied voltage from 0V to 150V.

  • Thin electrowetting controlled optical system with pan/tilt and variable focus functions

    A. Takei, E. Iwase, K. Matsumoto, I. Shimoyama

    TRANSDUCERS '07 & EUROSENSORS XXI, DIGEST OF TECHNICAL PAPERS, VOLS 1 AND 2    2007  [Refereed]

     View Summary

    In this paper, we proposed a thin optical system which has pan/tilt and variable focus functions for a small camera. Our optical system is composed of a tunable water prism and a tunable oil lens driven by electrowetting. The optical system can keep its thickness thin, because the oil lens is inside the prism and both of them are controlled on the same plate. In this research, we achieved the optical system capable of shifting the view direction 1.5 degrees and changing the focal plane from 25 mm to 12.5 mm. The thickness of the optical system is 2.5 mm.

  • A design method for out-of-plane structures by multi-step magnetic self-assembly

    E Iwase, Shimoyama, I

    SENSORS AND ACTUATORS A-PHYSICAL   127 ( 2 ) 310 - 315  2006.03  [Refereed]

     View Summary

    We provide the design method of multi-step magnetic self-assembly using ferromagnetic-hinged structures. The process uses the magnetostatic torque generated by an external magnetic field perpendicular to the substrate to lift hinged structures. Hinged structure is composed of a rigid plate connected by elastic hinges to one side of a substrate. If hinged structures are raised in sequential order, it is possible to assemble like Japanese "origami" complex three-dimensional structures. In our previous study, we found that a dimensionless factor that depends on its shape determines the sensitivity of the hinged microstructures to a magnetic field. This factor can be used as a criterion in designing a process for sequential batch self-assembly, because the factor indicates the differences in the sensitivity. In this study, we designed multi-step sequential assembly by using the dimensionless factor. Four-step sequential batch assembly was demonstrated using this method. This method will be useful for optical systems, which consist of many complex three-dimensional structures. (c) 2006 Elsevier B.V. All rights reserved.

    DOI

  • Angle tunable liquid wedge prism driven by electro-wetting

    A Takei, E Iwase, K Hoshino, K Matsumoto, Shimoyama, I

    MEMS 2006: 19TH IEEE INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS, TECHNICAL DIGEST     36 - 39  2006  [Refereed]

     View Summary

    We proposed a wedge prism which is tunable by electrowetting actuation. The wedge prism is useful for a small camera or an endoscope, because the wedge prism is capable of changing the view without a large instrument. Our prism consists of two plates facing each other and liquid sandwiched between the plates. By changing the angle between the two plates, the liquid and the two plates form into the wedge shape. We used electrowetting to change the angle of the prism. The wedge prism keeps the size small, since the liquid driven by electrowetting works as a prism. In addition, the prism keeps the view clear because the optical flatness of the wedge prism is determined by the flatness of the two plates. In this research, we achieved the wedge prism with which we can shift the field of view to the right and the left.

  • &lt;bold&gt;A SURFACE PLASMON RESONANCE SENSOR WITH A V-SHAPED SILICON PRISM ARRAY&lt;/bold&gt;

    N Tsujiuchi, E Iwase, K Hoshino, K Matsumoto, Shimoyama, I

    MEMS 2006: 19TH IEEE INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS, TECHNICAL DIGEST     522 - 525  2006  [Refereed]

     View Summary

    A surface plasmon resonance (SPR) sensor with a prism array made by silicon microfabrication techniques is proposed. We fabricated silicon prisms arrayed in 200 gm in pitch by anisotropic wet etching for deflecting light. We measured SPR curves in specimen of air, water and ethanol using near-infrared laser light (1550 nm) and obtained the SPR dip in each measurement. We fabricated a flexible flap, which was actuated by Lorentz force, to change the incident angle. The silicon prism chip was attached on the flap, the SPR curve was measured by scanning the incident angle of laser light with the flap.

  • Multistep sequential batch assembly of three-dimensional ferromagnetic microstructures with elastic hinges

    E Iwase, Shimoyama, I

    JOURNAL OF MICROELECTROMECHANICAL SYSTEMS   14 ( 6 ) 1265 - 1271  2005.12  [Refereed]

     View Summary

    In this paper, we have developed a process for multistep sequential batch assembly of complex three-dimensional (3-D) ferromagnetic microstructures. The process uses the magnetic torque generated by an external magnetic field perpendicular to the substrate to lift hinged structures. We found that a dimensionless factor that depends on the volume of the magnetic material and the stiffness of the hinges determines the sensitivity of the hinged microstructures to a magnetic field. This factor was used as a criterion in designing a process for sequential batch assembly, i.e., for setting appropriate differences in sensitivity. Using a dimensionless factor in the design of the sequential assembly simplified the assembly process, which requires only placing the structures on a permanent magnet, and which can be used to carry out multistep sequential batch assembly. We fabricated hinged microstructures, which consist of 4.5-mu m-thick electroplated Permalloy plates and 200-nm-thick nickel elastic hinges of various sizes. In an experiment, four plates (600 mu m x 800 mu m) were lifted sequentially and out-of-plane microstructures were assembled in a four-step process. Assembly of more complex out-of-plane microstructures (e.g., regular tetrahedrons; 800 mu m long on one side) was also shown to be feasible using this method of sequential batch assembly.

    DOI CiNii

  • "Pop-up" display with 3-dimensional microlens structures

    M Tohara, E Iwase, K Hoshino, K Matsumoto, Shimoyama, I

    MEMS 2005 Miami: Technical Digest     231 - 234  2005  [Refereed]

     View Summary

    In this paper, we demonstrate a "Pop-up" display. This display provides a pop-up image in the air with double-layered plane-convex microlenses and a hole array. This microlens array is fabricated by melting photoresists and form transfer [1] [2]. The height and diameter of the microlens was 34.6 mu m and 198 mu m, therefore the focal length was calculated as 318 mu m. To inspect the pop-up length, we estimated the position of the focal plane by measuring the light intensity of the image. The "Pop-up" image was formed at 2750 mu m higher from the original image on the display. In addition, we proved that the lens part needs no alignment with the original image.

  • Multi-step sequential batch self-assembly of three-dimensional micro-structures using magnetic field

    E Iwase, Shimoyama, I

    MEMS 2005 MIAMI: TECHNICAL DIGEST     588 - 591  2005  [Refereed]

     View Summary

    We have developed a process for multi-step sequential batch self-assembly of complex three-dimensional ferromagnetic micro-structures. The process uses the magnetic torque generated by an external magnetic field perpendicular to the substrate to lift hinged-structures. In our previous study, we found that a non-dimensional factor that depends on its shape determines the sensitivity of the micro hinged-structures to a magnetic field. This factor can be used as a criterion in designing a process for sequential batch self-assembly, because the factor indicates the differences in the sensitivity. In this study, we designed multi-step sequential assembly by using the non-dimensional factor. Four-step sequential batch assembly was demonstrated using this method.

  • A Turning Gait Generating Network for a Hexapod Robot

    岩瀬英治, 加藤慎一朗, 安田隆, 下山勲

    日本ロボット学会誌   22 ( 4 ) 492 - 498  2004  [Refereed]

     View Summary

    This paper describes a gait generating network for a hexapod robot under various curvature turnings. Formica japonica Motschulsky, that is one of major ant with about 6 [mm] body length in Japan, was used for a gait analysis. Movements of the leg joints during free walking was recoded at 60 to 250 [frame/s] by a high-speed video camera. From the data, we found that the turning gaits were classified into two distinct patterns: a sharp turning gait in which case the radius of curvature is under 5 [mm], a gradual turning gait in which case that is 5 to 40 [mm] . A turning gait generating network, which was possible to generate each gait and to vary a radius of curvature, was devised. That is a neural network which is described by neurons and connections between them using excitation and inhibition. We made a hexapod robot with 3 DOF each leg and verified the accountability of the gait generating network using the robot. As a result, smooth and stable turning in different curvatures was achieved.

    DOI CiNii

  • Sequential Batch Assembly of 3-D Microstructures by using a Magnetic Anisotropy and a Magnetic Field

    Eiji Iwase, Isao Shimoyama

    IEEJ Transactions on Sensors and Micromachines   123 ( 7 ) 224 - 230  2003  [Refereed]

     View Summary

    This paper describes three-dimensional (3-D) microstructure assembly using an external magnetic field. An external magnetic field perpendicular to a substrate lifts a hinged structure by the torque due to the shape magnetic anisotropy. We made micro flap structures (4.5 μm-thick electroplated Permalloy) which have 0.2 μ,m-thick nickel elastic hinges in various size, and made lift the structures in a magnetic field up to 50 kA/m. We demonstrated that the non-dimensional factor depending on the volume of magnetic material and the stiffness of the hinges determine the sensitivity to the magnetic field. As a result, we realized sequential batch assembly using the difference of the sensitivity. The each two plates 600 μm x 600 μm in size were lifted sequentially, and out-of-plane microstructures were assembled. And the complex out-of-plan microstructures, the regular tetrahedrons 800 μm on a side with a closed linkage were able to assemble by our method. © 2003, The Institute of Electrical Engineers of Japan. All rights reserved.

    DOI CiNii

  • Sequential batch assembly of 3-D microstructures with elastic hinges by a magnetic field

    E Iwase, S Takeuchi, Shimoyama, I

    FIFTEENTH IEEE INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS, TECHNICAL DIGEST     188 - 191  2002  [Refereed]

     View Summary

    This paper describes three-dimensional (3-D) microstructure assembly using an external magnetic field. An external magnetic field perpendicular to a substrate lifts up a hinged structure due to the shape magnetic anisotropy. Micro, flap structures (4.5 mum-thick electroplated Permalloy) having 0.2 mum-thick nickel elastic hinges with various lengths and widths are bent in out-of-plane direction in a magnetic field up to 50 kA/m. The volume of magnetic material and the stiffness of the hinges determine the sensitivity to a magnetic field. As a result, we realized sequential batch assembly using the difference of the sensitivity. By way of the example, we have erected plates 600 mum x 600 mum in size. Also, structures bent at 90 and 45 degrees out of the plane have been obtained at the same time.

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Books and Other Publications

  • Origami6: II. Technology, Art, Education

    Eiji Iwase, Isao Shimoyama( Part: Contributor, Magnetic Self-Assembly of Three-Dimensional Microstructures)

    American Mathematical Society  2016.01 ISBN: 9781470418762

  • ウェアラブルデバイスの小型、薄型化と伸縮、柔軟性の向上技術

    岩瀬英治, 古志知也( Part: Contributor, 自己修復型金属配線の開発とウェアラブル機器への応用可能性, (第2章 第6節))

    技術情報協会  2015.12 ISBN: 9784861046063

Misc

  • 自己修復型金属配線と伸縮デバイス応用

    古志知也, 岩瀬英治

    応用物理   86 ( 12 ) 1061 - 1064  2017.12  [Refereed]  [Invited]

    Article, review, commentary, editorial, etc. (scientific journal)  

  • 伸縮性電気配線および自己修復機能を有する金属配線

    古志知也, 岩瀬英治

    接着の技術   37 ( 2 ) 21 - 25  2017  [Refereed]  [Invited]

    Article, review, commentary, editorial, etc. (scientific journal)  

  • 2G26 Layer composition of multi-layered film for unfoldable cell transplantation sheet in body

    SHIMBO Sota, FUJIE Toshinori, IWASE Eiji

      2016 ( 28 ) "2G26 - 1"-"2G26-5"  2016.01

     View Summary

    We propose a sheet shape controlling method of tens/hundreds-nm-thick polymer film (called "nanosheet") by using a triple-layered structure and consider composition of the triple-layered structure. The triple-layered structure includes a nanosheet, a stretching layer with internal stress and a supporting layer. The supporting layer and the stretching layer were dissolved in water. The triple-layered structure was folded into a cylindrical shape due to the internal stress and unfolded into a flat shape after dissolution of a stretching layer. In this paper, we considered the solubility and swelling property of the supporting layer and the stretching layer, and considered compositions of the triple-layered structure which is a parameter of unfolding. After soaking in water, Type-A composition (stretching layer - supporting layer - nanosheet) was unfolded into a flat shape, and immediately after folded into a cylindrical shape because of swelling strain mismatch of supporting layer and stretching layer. However, Type-B composition (stretching layer - nanosheet - supporting layer) was able to keep a flat shape after unfolding because swelling strain of the stretching layer and the supporting layer were the same. Therefore, the type-B composition can reduce influence of swelling.

    CiNii

  • 28am2-E-5 Particle Behavior Analysis on Electric Field Trapping of Metal Nanoparticles

    NAKAJIMA Yuta, KOSHI Tomoya, IWASE Eiji

      2015 ( 7 ) "28am2 - E-5-1"-"28am2-E-5-2"  2015.10

     View Summary

    We analyzed a particle behavior of metal nanoparticles under electric field trapping by directly observing. Electric field trapping is the nanoparticles in the solution is collected toward narrow gap by dielectrophoresis force. We found that the nanoparticles are collected to bridging part, even after the particles are bridged over a narrow gap. Therefore, we fabricated gold wires with a narrow gap and measured diameter of particle cloud corresponding to applied voltage. The diameter of the particle cloud obviously increases as the applied voltage increases. We expect this phenomenon would enable to contribute to additional nanoparticle assembling which is useful for self-healing wire with high healing ability.

    CiNii

  • 29pm2-B-4 Micropatterning of multiple types of photonic colloidal crystals by channel-cut method

    Suzuki Noriyuki, Iwase Eiji, Onoe Hiroaki

      2015 ( 7 ) "29pm2 - B-4-1"-"29pm2-B-4-2"  2015.10

     View Summary

    This paper describes a simple micropatterning method of multiple types of photonic colloidal crystals (PCCs) on a single substrate for an optical color filter attached to a monochromic reflective display. We developed a "channel-cut method" to introduce multiple colloidal suspensions selectively and sequentially into a microchannel network. Colloidal suspensions are crystallized by centrifugal force. We succeeded in patterning of three different PCCs made of polystyrene in a single-layered microchannel. These PCCs exhibit red, blue and green structural color, respectively. We believe that our patterning method will realize a colorized reflective display that achieves low energy consumption and high color expression.

    CiNii

  • 29pm1-F-3 Self-healing of crack on stretching wire

    KOSHI Tomoya, IWASE Eiji

      2015 ( 7 ) "29pm1 - F-3-1"-"29pm1-F-3-2"  2015.10

     View Summary

    This paper reports self-healing of a crack on a stretching metal wire using electric field trapping of metal nanoparticles. The electric field trapping is a phenomenon where the nanoparticles are trapped in a crack on the wire selectively by the electric field, when a voltage is applied to the wire covered with the nanoparticle dispersion. For realizing the self-healing on the stretching wire, we designed elongation stiffnesses of layers of a metal wire and a stretchable substrate in order to control the number of cracks which determine an applied voltage required for the self-healing (healing voltage). This approach enable us to estimate the crack width and the healing voltage. First, we analyzed the deformation of the metal wire on the stretchable substrate to design the elongation stiffnesses. Next, we fabricated the designed metal wire on the stretchable substrate and verified the self-healing on the stretching wire.

    CiNii

  • 30pm1-E-1 A coloring element using a bending deformation of an electroactive elastomer with bottom-arranged electrodes

    USUKI Kodai, ONOE Hiroaki, IWASE Eiji

      2015 ( 7 ) "30pm1 - E-1-1"-"30pm1-E-1-2"  2015.10

     View Summary

    By using a bending deformation of an electroactive elastomer, we proposed and fabricated a deformable coloring element. The proposed element is composed of a flexible plate of TiO_2-loaded PDMS (TL-PDMS) and bottom-arranged electrodes. TL-PDMS is used because of durability, response speed, and producibility. The bottom arrangement of electrodes achieves a simple fabrication for a display device. In this paper, we measured the time response of the repetitive bending deformation of a TL-PDMS with bottom-arranged electrodes to find the bending-characteristic of TL-PDMS. Finally, we fabricated a 1 × 3 dot array of proposed coloring elements and demonstrated a color change by using bending deformation of TL-PDMS.

    CiNii

  • 20pm3-PM029 Optical properties of colloidal crystal element for reflective display

    Suzuki Noriyuki, Iwase Eiji, Onoe Hiroaki

      2014 ( 6 ) "20pm3 - PM029-1"-"20pm3-PM029-2"  2014.10

     View Summary

    Colloidal crystals only reflect light having a specific wavelength in incident light by Bragg diffraction. In this paper, we propose a method to colorize a reflective display using a structural color filter made by photonic colloidal crystals colorize a black and white reflective display. We fabricated a structural color filter, which made of crystallized polystyrene colloids, by evaporation on a glass slide. We analyzed the crystal structure of color filter by SEM images and evaluated the optical properties by measuring reflection spectra of the crystal, which is placed on a white or black substrate. We demonstrated the feasibility of the colorization of reflective displays.

    CiNii

  • 21pm1-A3 Particle Size Dependence on a Self-Healing Wire using an Electric Field Trapping of Gold Nanoparticles

    KOSHI Tomoya, IWASE Eiji

      2014 ( 6 ) "21pm1 - A3-1"-"21pm1-A3-2"  2014.10

     View Summary

    On a self-healing wire using an electric field trapping of gold nanoparticles, we examined a particle size dependence of a healing voltage by comparing 20 nm and 200 nm in particle radii. We fabricated the gold wires with a patterned crack on a glass substrate, and measured the healing voltages. As a result, in the each case of 20 nm and 200 nm in particle radii, cracks up to 1000 nm were healed by applying under 3.2 V in amplitude of AC voltage, and cracks up to 3500 nm were healed by applying under 4.0 V in amplitude of AC voltage, respectively. This result shows that the case of 200 nm in particle radius can heal a larger crack by applying the same voltage than the case of 20 nm in particle radius.

    CiNii

  • Bush-Cricket-Inspired Acoustic Sensor for Sound Localization with One Sensor

    稲葉亮, NGUYEN Minh Dung, 高橋英俊, 岩瀬英治, 松本潔, 下山勲

    日本ロボット学会学術講演会予稿集(CD-ROM)   27th   ROMBUNNO.2I1-03  2009.09

    J-GLOBAL

  • An Autostereoscopic Method Using a Parallax Barrier and a Microlens Array

    奥野和秀, 岩瀬英治, 松本潔, 下山勲

    日本ロボット学会学術講演会予稿集(CD-ROM)   27th   ROMBUNNO.3A3-06  2009.09

    J-GLOBAL

  • Measurement of differential pressure on wing surface using an ornithopter modeled on insects

    青山雄一郎, 大澤一治, 高橋英俊, 岩瀬英治, 松本潔, 下山勲

    日本ロボット学会学術講演会予稿集(CD-ROM)   27th   ROMBUNNO.1M3-07  2009.09

    J-GLOBAL

  • 540 Planar Near-Infrared Surface Plasmon Resonance Sensor with Grating Coupler and Si Prism

    KAN Tetsuo, TSUJIUCHI Naoko, IWASE Eiji, MATSUMOTO Kiyoshi, SHIMOYAMA Isao

    年次大会講演論文集 : JSME annual meeting   2008 ( 8 ) 279 - 280  2008.08

     View Summary

    We have developed a Si microfabrication based SPR (Surface Plasmon Resonance) sensor chip equipped with Si prisms and an optical grating for sensor miniaturization. The Si prism structure was used to introduce the Near-Infrared light (λ = 1550 nm) to the sensing surface and generating the evanescent light there. Smooth prism slope was fabricated by utilizing (111) planes on the (100) plane of single crystalline Si wafer by anisotropic etching, giving small 200-μm prism array with 54.74° slope angle. We also used the optical grating with about 400-μm-pitch to manipulate an SPR dip position so as to increase the design freedom of the optical path within the sensor. SPR measurements with several specimens confirmed that the combination of Si prisms and the optical grating successfully worked to excite Surface Plasmon so that the sensor&#039;s validity as a refractive index sensor was also confirmed. Since this sensor is compatible with a Si microfabrication technology, further integration of optical parts, fluidic components and miniaturization of SPR sensor becomes possible, which is necessary for the application of an SPR sensor toward an environmental sensor.

    DOI CiNii

  • 2P1-A22 Wireless Signal Transmitting System Driven by Piezoelectric Generator

    SUZUKI Kotaro, IWASE Eiji, MATSUMOTO Kiyoshi, SHIMOYAMA Isao

      2008   "2P1 - A22(1)"-"2P1-A22(4)"  2008.06

     View Summary

    We propose a wireless signal transmitting system by gaining energy from the surroundings. As all of energy needed by this system is gained from the surroundings, there are no necessities for refilling fuel or changing battery. For example, Tire Pressure Monitoring System (TPMS) needs such a maintenance-free sensor system. The system consists of a piezoelectric generator, a capacitor, and a circuit. The circuit watches the capacitor's storage and supplies energy to the transmitter. We made an experiment to gain energy from the deformation of a car wheel with the generator. The energy from the environment is estimated to be about 20mW. This estimation shows that we can drive a transmitter for 1 second after 7 second's charge. We were also able to drive the transmitter in another environment from which the generator gains a little energy, so this system is available not only on wheel's surface but also in general environments.

    CiNii

  • Study of Impact Force Measurement on a Golf Club

    長谷川輝, 田中悠輔, 岩瀬英治, 松本潔, 下山勲

    日本機械学会ロボティクス・メカトロニクス講演会講演論文集(CD-ROM)   2008   ROMBUNNO.1A1-H14  2008.06

    J-GLOBAL

  • A Micro Ultrasonic Wave Sensor Using Helmholtz Resonance

    鈴木明, 高橋英俊, 岩瀬英治, 松本潔, 下山勲

    日本機械学会ロボティクス・メカトロニクス講演会講演論文集(CD-ROM)   2008   ROMBUNNO.1P1-H08  2008.06

    J-GLOBAL

  • The Estimation of Surface Shape Using Lined Strain Sensors

    宮本良, 小松哲, 岩瀬英治, 松本潔, 下山勲

    日本機械学会ロボティクス・メカトロニクス講演会講演論文集(CD-ROM)   2008   ROMBUNNO.1P1-I05  2008.06

    J-GLOBAL

  • A Study of Insect Flight Using Motor-driven Ornithopter

    加藤浩気, 橋本温之, 岩瀬英治, 松本潔, 下山勲

    日本機械学会ロボティクス・メカトロニクス講演会講演論文集(CD-ROM)   2008   ROMBUNNO.1P1-F04  2008.06

    J-GLOBAL

  • Surface Shape Detection with Shear Stress Sensor

    石滝公一, 岩瀬英治, 松本潔, 下山勲

    日本機械学会ロボティクス・メカトロニクス講演会講演論文集(CD-ROM)   2007   1A2-A11  2007.05

    J-GLOBAL

  • The Detection of Center of Gravity for Stable Grasp by Using a Shear Stress Sensor

    田中悠輔, 森本雄矢, 岩瀬英治, 松本潔, 下山勲

    日本機械学会ロボティクス・メカトロニクス講演会講演論文集(CD-ROM)   2007   1A2-A10  2007.05

    J-GLOBAL

  • The structural-color reflective dot-matrix display

    岩瀬英治, 松本潔, 下山勲

    日本ロボット学会学術講演会予稿集(CD-ROM)   24th   2A25  2006.09

    J-GLOBAL

  • ナノ表面構造による機能発現

    岩瀬英治, 尾上弘晃, 下山勲

    機械の研究   57 ( 1 ) 182 - 188  2005  [Refereed]  [Invited]

    Article, review, commentary, editorial, etc. (scientific journal)  

  • 有機半導体を用いた複眼型フレキシブルフォトセンサ

    斎藤宏, 岩瀬英治, 星野一憲, 松本潔, 下山勲

    応用物理学関係連合講演会講演予稿集   51st ( 3 ) 1489  2004.03

    J-GLOBAL

  • 2P2-61-088 6 脚ロボットの方向転換時の歩容に関する研究

    岩瀬 英治, 加藤 慎一朗, 安田 隆, 下山 勲

    ロボティクス・メカトロニクス講演会講演概要集   2000   104 - 104  2000

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    アリの歩行を高速度カメラを用いて撮影を行い, 各脚の各節の座標データを抽出し, 脚運びについて数値化した。これの解析から, アリの方向転換時の歩容を分類し, それぞれについて歩容を実現する自律分散的なアルゴリズムを考案した。また, 6脚ロボットを製作し, このアルゴリズムの有効性を検証した。その結果, 6脚ロボットにおいて, ロバスト性が高くかつ滑らかな方向転換行動を実現することができた。

    CiNii

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Industrial Property Rights

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Works

  • 紙とテクノロジー,「折り紙の呼吸 Breathing of ORIGAMI」展,紙に命を与える折りと技術 ((株)竹尾,見本帖本店展示企画)

    2014
     
     

Awards

  • “Inno”vation Program, Generation Award in the Sensing/Data Category

    2017.11   Ministry of Internal Affairs and Communications (MIC)  

    Winner: IWASE Eiji

  • Certificate of Merit for New Field Development

    2017.11   Micro-Nano Science & Technology Division, the Japan Society of Mechanical Engineering (JSME)  

    Winner: IWASE Eiji

  • Waseda Research Award (High-Impact Publication)

    2016.11   Waseda University  

    Winner: IWASE Eiji

  • Okuma Memorial Academic Prize (Encouragement Award)

    2016.11   Waseda University  

    Winner: IWASE Eiji

  • The 19th Marubun Research and Encouragement Award

    2016.04   Marubun Research Promotion Foundation  

    Winner: IWASE Eiji

  • MNC 2014 Outstanding Paper

    2015.11   27th International Microprocesses and Nanotechnology Conference (MNC2014)  

    Winner: IWASE Eiji

  • The Commendation for Science and Technology by the Minister of Education, Culture, Sports, Science and Technology, The Young Scientists’ Prize

    2015.04   Minister of Education, Culture, Sports, Science and Technology (MEXT)  

    Winner: IWASE Eiji

  • Konica Minolta Imaging Science Encouragement Award (Outstanding)

    2014.03   Konica Minolta Science and Technology Foundation  

    Winner: IWASE Eiji

  • The 20th Konica Minolta Imaging Science Encouragement Award (Outstanding)

    2014  

  • Funai Information Technology Award

    2013.04   Fuani Foundation for Information Technology (FFIT)  

    Winner: IWASE Eiji

  • The 12th Funai Information Technology Award, Fuani Foundation for Information Technology (FFIT)

    2013  

  • Outstanding Technical Paper Award

    2009.04   Japan Institute of Electronics Packaging (JIEP)  

    Winner: IWASE Eiji

  • Best Paper Award, Japan Institute of Electronics Packaging (JIEP)

    2009  

  • The 8th Igarashi Award

    2005.10   The Institute of Electrical Engineers of Japan (IEEJ)  

    Winner: IWASE Eiji

  • The 8th Igarashi Award, the Institute of Electrical Engineers of Japan (IEEJ)

    2005  

  • The 17th Young Investigator Excellence Award

    2002.09   The Robotics Society of Japan (RSJ)  

    Winner: IWASE Eiji

  • The 17th Young Investigator Excellence Award, the Robotics Society of Japan (RSJ)

    2002  

  • Hatakeyama Award

    2000.03   The Japan Society of Mechanical Engineering (JSME)  

    Winner: IWASE Eiji

  • Hatakeyama Award, the Japan Society of Mechanical Engineering (JSME)

    2000  

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Research Projects

  • 折り紙エレクトロニクス

    日本学術振興会  科学研究費・基盤研究(A)

    Project Year :

    2018
    -
    2020
     

    岩瀬 英治

  • 断線を自ら診断し自己修復する金属配線

    日本学術振興会  科学研究費・基盤研究(B)特設分野研究

    Project Year :

    2016.08
    -
    2018
     

    岩瀬 英治

  • 単一駆動部による多自由度MEMSスキャナの制御とそのデバイス応用

    日本学術振興会  科学研究費・若手研究(A)

    Project Year :

    2015
    -
    2017
     

    岩瀬 英治

  • さまざまな模様・質感が提示可能な柔軟シート

    日本学術振興会  科学研究費・挑戦的萌芽研究

    Project Year :

    2015
    -
    2016
     

    岩瀬 英治

  • Stamping transfer method for large-area, function-integration, flexible MEMS devices

    Japan Society for the Promotion of Science (JSPS)  Grant-in-Aid for Young Scientists (A)

    Project Year :

    2007
    -
    2008
     

    Eiji Iwase

  • ナノ・マイクロ可動機構による光アクティブ制御

    日本学術振興会  科学研究費・特別研究員奨励費

    Project Year :

    2004
    -
    2005
     

    岩瀬 英治

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Presentations

  • Programmable Medicine: Autonomous, Ingestible, Deployable Hydrogel Patch and Plug for Stomach Ulcer Therapy

    Alexis du, Plessis d’Argentre, Samuel Perry, Yoshitaka Iwata, Haruna Iwasaki, Eiji Iwase, Assunta Fabozzo, Iain Will, Daniela Rus, Dana Damian, Shuhei Miyashita

    Proceedings of the 2018 IEEE International Conference on Robotics and Automation (ICRA2018) 

    Presentation date: 2018.05

  • Self-Rolling up Micro Assembly using Temperature-Responsive Hydrogel Sheet with Rigid Plate Array

    Yoshitaka Iwata, Shuhei Miyashita, Eiji Iwase

    Proceedings of the 31st IEEE International Conference on Micro Electro Mechanical Systems (MEMS2018) 

    Presentation date: 2018.01

  • Micro Sample Chamber by Laminated Fluorinated Films for NMR Spectroscopy of a Micro-volume Spherical Sample

    Takuma Hizawa, Masato Takahashi, Eiji Iwase

    Proceedings of the 30th International Microprocesses and Nanotechnology Conference (MNC2017) 

    Presentation date: 2017.11

  • Measurement of Conformability and Adhesion Energy of Ultrathin Film to Skin Model

    Junki Sugano, Toshinori Fujie, Hiroyasu Iwata, Eiji Iwase

    Proceedings of the 30th International Microprocesses and Nanotechnology Conference (MNC2017) 

    Presentation date: 2017.11

  • Epidermal pH-Sensor Capable of Operating only with NFC Energy Harvesting

    Shun Miyabayashi, Hiroki Hayata, Eiji Iwase, Toshinori Fujie, Hiroyasu Iwata

    Proceedings of the 8th International Conference on Flexible and Printed Electronics (ICFPE2017) 

    Presentation date: 2017.07

  • Effect of Living Body on Performance of RF Identifier Antenna Printed on Ultrathin Polymer Film

    Hiroki Hayata, Marin Okamoto, Shinji Takeoka, Eiji Iwase, Toshinori Fujie, Hiroyasu Iwata

    Proceedings of the 8th International Conference on Flexible and Printed Electronics (ICFPE2017) 

    Presentation date: 2017.07

  • Printed Paper Robot Driven by Electrostatic Actuator

    Hiroki Shigemune, Shingo Maeda, Vito Cacucciolo, Yoshitaka Iwata, Eiji Iwase, Shuji Hashimoto, Shigeki Sugano

    Proceedings of the 2017 IEEE International Conference on Robotics and Automation (ICRA2017) 

    Presentation date: 2017.05

  • Stretchable Electronic Device with Repeat Self-Healing Ability of Metal Wire

    Tomoya Koshi, Eiji Iwase

    Proceedings of the 30th IEEE International Conference on Micro Electro Mechanical Systems (MEMS2017) 

    Presentation date: 2017.01

  • Hybrid Film for Self-Adhesion and Shape-Controlling

    Sota Shimbo, Toshinori Fujie, Eiji Iwase

    Proceedings of the 30th IEEE International Conference on Micro Electro Mechanical Systems (MEMS2017) 

    Presentation date: 2017.01

  • Stress-Free Stretchable Electronic Device using Folding Deformation

    Yoshitaka Iwata, Eiji Iwase

    Proceedings of the 30th IEEE International Conference on Micro Electro Mechanical Systems (MEMS2017) 

    Presentation date: 2017.01

  • Voltage and Current Condition on Self-Healing Metal Wire

    Tomoya Koshi, Eiji Iwase

    Proceedings of the International Symposium on Micro-Nano Science and Technology 2016 (MNST2016) 

    Presentation date: 2016.12

  • Dielectric Microactuator using Dielectrophoretic Force

    Kensuke Ohtsuka, Eiji Iwase

    Proceedings of the International Symposium on Micro-Nano Science and Technology 2016 (MNST2016) 

    Presentation date: 2016.12

  • Characterization of Transfer Positioning Accuracy on Roll-Type Stamping Transfer

    Makoto Tokonami, Eiji Iwase

    Proceedings of the International Symposium on Micro-Nano Science and Technology 2016 (MNST2016) 

    Presentation date: 2016.12

  • Healing Process Behavior on Electric Field Trapping of Gold Nanoparticles

    Yuta Nakajima, Tomoya Koshi, Eiji Iwase

    Proceedings of the International Symposium on Micro-Nano Science and Technology 2016 (MNST2016) 

    Presentation date: 2016.12

  • Observation of Mechanical Stimulus Effect on Cell Culture using Magnetically-Driven Structures

    Noriyuki Fukui, Kaori Kuribayashi-Shigetomi, Hiroaki Onoe, Eiji Iwase

    Proceedings of the International Symposium on Micro-Nano Science and Technology 2016 (MNST2016) 

    Presentation date: 2016.12

  • Shape Evaluation of a Micro-Volume Sample Chamber for NMR Measurement

    Takuma Hizawa, Masato Takahashi, Eiji Iwase

    Proceedings of the International Symposium on Micro-Nano Science and Technology 2016 (MNST2016) 

    Presentation date: 2016.12

  • Optical Characteristics of Flat-Top and Dome-Shape Patterned Photonic Colloidal Crystals

    Noriyuki Suzuki, Eiji Iwase, Hiroaki Onoe

    Proceedings of the International Symposium on Micro-Nano Science and Technology 2016 (MNST2016) 

    Presentation date: 2016.12

  • Operation of Three-Dimensional MEMS Mirror by Single Superposed Driving Signal

    Toshiya Nagasawa, Yohei Oguchi, Eiji Iwase

    Proceedings of the 29th International Microprocesses and Nanotechnology Conference (MNC2016) 

    Presentation date: 2016.11

  • Multiple-Colored Flexible Optical Filter with Patterned Photonic Colloidal Polymer Gels

    Noriyuki Suzuki, Eiji Iwase, Hiroaki Onoe

    Proceedings of the 20th International Conference on Miniaturized Systems for Chemistry and Life Sciences (microTAS2016) 

    Presentation date: 2016.10

  • Development of Inexpensive Skin Adhesive Electronic Device - RFID Tag Implementation on Ultrathin Polymer Film -

    Hiroki Hayata, Marin Okamoto, Shinji Takeoka, Eiji Iwase, Toshinori Fujie, Hiroyasu Iwata

    Proceedings of the 7th International Conference on Flexible and Printed Electronics (ICFPE2016) 

    Presentation date: 2016.09

  • Assembly on a MEMS Scale using Magnetic Field

    Isao Shimoyama, Eiji Iwase  [Invited]

    Proceedings of the 2016 MRS Spring Meeting & Exhibit 

    Presentation date: 2016.03

  • Microfluidic Patterning of Hemispherical Dome-Shape Photonic Colloidal Crystals for Wide-Viewing-Angle Reflective Display

    Noriyuki Suzuki, Eiji Iwase, Hiroaki Onoe

    Proceedings of the 29th IEEE International Conference on Micro Electro Mechanical Systems (MEMS2016) 

    Presentation date: 2016.01

  • Ultra-Conformable Polymer Nanosheets with Inkjet-Printed Electric Circuits

    Marin Okamoto, Toshinori Fujie, Mizuho Kurotobi, Kento Yamagishi, Atsushi Murata, Eiji Iwase, Hiroyasu Iwata, Shinji Takeoka

    Proceeding of the 2015 International Chemical Congress of Pacific Basin Societies (PACIFICHEM2015) 

    Presentation date: 2015.12

  • The Three-dimensional Actuation of the MEMS Scanner with Single Pair of Beams and Single Driving System

    Yohei Oguchi, Chisa Iino, Eiji Iwase

    Proceedings of the 28th International Microprocesses and Nanotechnology Conference (MNC2015) 

    Presentation date: 2015.11

  • Design Method for Cylindrical Self-Folding of Films using a Triple-Layered Structure with Internal Stress

    Sota Shimbo, Toshinori Fujie, Eiji Iwase

    Proceedings of the 28th International Microprocesses and Nanotechnology Conference (MNC2015) 

    Presentation date: 2015.11

  • Micropatterning of Multiple Photonic Colloidal Crystals in Single-Layered Microchannels for Structural-Color Optical Filter

    Noriyuki Suzuki, Eiji Iwase, Hiroaki Onoe

    Proceedings of the 18th International Conference on Solid-State Sensors 

    Presentation date: 2015.06

  • Flexible Devices using Rigid Materials - Device Integration Method and Self-Healing Metal Wire

    Eiji Iwase  [Invited]

    Proceedings of the 6th International Symposium on Advanced Materials Development and Integration of Novel Structured Metallic and Inorganic Materials (AMDI-6) 

    Presentation date: 2015.06

  • Strong Mechanical Nonlinearity of Optomechanically Driven Suspended Photonic Crystal Membrane

    Pui-Chuen Hui, Alejandro W. Rodriguez, David Woolf, Eiji Iwase, Mughees Khan, Federico Capasso, Marko Loncar

    Proceedings of the Conference on Lasers and Electro-Optics (CLEO/QELS:2015) 

    Presentation date: 2015.05

  • Self-healing Metal Wire using an Electric Field Trapping of Gold Nanoparticles for Flexible Devices

    Tomoya Koshi, Eiji Iwase

    Proceedings of the 28th IEEE International Conference on Micro Electro Mechanical Systems (MEMS2015) 

    Presentation date: 2015.01

  • Bottom Arranged Electrodes in an Electroactive Hydrogel Flexible Coloring Element for a High Fill-factor

    Kodai Usuki, Hiroaki Onoe, Eiji Iwase

    Proceedings of the 27th International Microprocesses and Nanotechnology Conference (MNC2014) 

    Presentation date: 2014.11

  • Design and Fabrication of a Self-Healing Metal Wire using an Electric Field Trapping of Gold Nanoparticles

    Tomoya Koshi, Eiji Iwase

    Proceedings of the 27th International Microprocesses and Nanotechnology Conference (MNC2014) 

    Presentation date: 2014.11

  • Magnetic Self-Assembly for Three-Dimensional Microstructures

    Eiji Iwase, Isao Shimoyama

    Proceedings of the 6th International Meeting on Origami in Science 

    Presentation date: 2014.08

  • Dynamics of a Tethered Silicon Photonic Crystal Membrane due to Optical Gradient, Photo-thermal and Casimir Forces

    Pui-Chuen Hui, David Woolf, Eiji Iwase, Irfan Bulu, Alejandro W. Rodriguez, Mughees Khan, Parag B. Deotare, Steven G. Johnson, Federico Capasso, Marko Loncar

    Proceedings of the Conference on Lasers and Electro-Optics (CLEO/QELS:2012) 

    Presentation date: 2012

  • Towards Optical Manipulation of Casimir Force using Free-standing Membranes with Engineered Optical and Mechanical Properties

    Eiji Iwase, Pui-Chuen Hui, David Woolf, Alejandro W. Rodriguez, Mughees Khan, Steven G. Johnson, Federico Capasso, Marko Loncar

    Proceedings of the Conference on Lasers and Electro-Optics (CLEO/QELS:2012) 

    Presentation date: 2012

  • Optomechanical Cooling, Amplification, and Bistability in Coupled-mode Suspended Waveguide Geometries

    David N. Woolf, Pui-Chuen Hui, Eiji Iwase, Alejandro W. Rodriguez, Mughees Kahn, Steven G. Johnson, Marko Loncar, Federico Capasso

    Proceedings of SPIE Photonics West (Photonics West 2012) 

    Presentation date: 2012

  • Simultaneous Assembly of Arrayed 3-D Microstructures using Magnetic Film

    岩瀬英治, 下山勲

    第19回日本ロボット学会学術講演会 

    Presentation date: 2011.11

  • Optical Bonding and Antibonding Forces in Assymetric Geometries for Casimir Force Detection

    David N. Woolf, Pui-Chuen Hui, Eiji Iwase, Alejandro W. Rodriguez, Alexander P. McCauley, Mughees Kahn, Steven G. Johnson, Marko Loncar, Federico Capasso

    Proceedings of the Conference on Lasers and Electro-Optics (CLEO/QELS:2011) 

    Presentation date: 2011

  • Long-Range SPR Sensor with Micro Liquid Channels for Maintaining Symmetrical Condition

    Tetsuo Kan, Hiroyuki Kojo, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 14th International Conference on Miniaturized Systems for Chemistry and Life Sciences (microTAS2010) 

    Presentation date: 2010

  • Integration Method of Bridging-Structural CNTs into Si Wafer by Stamping Transfer

    Yusuke Takei, Atsushi Hashimoto, Tetsuo Kan, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the International Conference on Electronics Packaging (ICEP2010) 

    Presentation date: 2010

  • Stretchable Liquid Tactile Sensor for Robot-Joints

    Kentaro Noda, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the The 2010 IEEE International Conference on Robotics and Automation (ICRA2010) 

    Presentation date: 2010

  • Sound Direction Sensor with an Acoustic Channel

    Minh Dung Nguyen, Akira Inaba, Akira Suzuki, Hideotoshi Takahashi, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 23rd IEEE International Conference on Micro Electro Mechanical Systems (MEMS2010) 

    Presentation date: 2010

  • Photoresponse Compensated Piezoresistive Cantilever under Fluorescence Measurement Environment

    Uijin Jung, Kenta Kuwana, Hidetoshi Takahashi, Kentaro Noda, Yusuke Takei, Tetsuo Kan, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 23rd IEEE International Conference on Micro Electro Mechanical Systems (MEMS2010) 

    Presentation date: 2010

  • Micro-Bead Force Sensor based on Aligned Metal Nanoparticle

    Asuto Koyama, Tetsuo Kan, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 23rd IEEE International Conference on Micro Electro Mechanical Systems (MEMS2010) 

    Presentation date: 2010

  • Triaxial Force Measurement Cantilever by Sidewall-Doping with Rapid Thermal Diffusion

    Yuichiro Aoyama, Binh-Khiem Nguyen, Kentaro Noda, Yusuke Takei, Tetsuo Kan, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 23rd IEEE International Conference on Micro Electro Mechanical Systems (MEMS2010) 

    Presentation date: 2010

  • Measurement of the Impact Stress in a Golf Club Head

    Akira Hasegawa, Akihito Nakai, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 23rd IEEE International Conference on Micro Electro Mechanical Systems (MEMS2010) 

    Presentation date: 2010

  • Thermal-Based Skin Moisture Device with Contact Pressure Sensor

    Koki Katoh, Yasumasa Ichikawa, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 23rd IEEE International Conference on Micro Electro Mechanical Systems (MEMS2010) 

    Presentation date: 2010

  • Adhesion Force Measurement between Silicon and Carbon Nanotubes Synthesized by Chemical Vapor Deposition

    Atsushi Hashimoto, Yusuke Takei, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 15th International Conference on Solid-State Sensors, Actuators and Microsystems (Transducers2009) 

    Presentation date: 2009

  • Sensitivity Enhancement by Micro Helmholtz Resonator for Ultrasonic Distance Sensor

    Akira Suzuki, Hidetoshi Takahashi, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 15th International Conference on Solid-State Sensors, Actuators and Microsystems (Transducers2009) 

    Presentation date: 2009

  • Self-Aligned Opposite Mirrors for Tilting Field of View Driven by Electrowetting

    Koutaro Suzuki, Atsushi Takei, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 15th International Conference on Solid-State Sensors, Actuators and Microsystems (Transducers2009) 

    Presentation date: 2009

  • Ellipsoidal Micro Lens fabricated by Depositing Parylene Directly on Liquid

    Ryo Miyamoto, Nguyen Binh-Khiem, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 15th International Conference on Solid-State Sensors, Actuators and Microsystems (Transducers2009) 

    Presentation date: 2009

  • Peristaltic Micropump fabricated by Depositing Parylene Directly on Liquid

    Satoshi Komatsu, Nguyen Binh-Khiem, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 15th International Conference on Solid-State Sensors, Actuators and Microsystems (Transducers2009) 

    Presentation date: 2009

  • Nano-Mechanical Structure Fabrication Technology for Highly Integrated, Complex MEMS

    Tetsuo Kan, Yusuke Takei, Hiroaki Onoe, Eiji Iwase, Tetsuji Dohi, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the International Conference on Electronics Packaging (ICEP2009) 

    Presentation date: 2009

  • Material Discrimination by Heat Flow Sensing

    Koki Katoh, Yasumasa Ichikawa, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 15th International Conference on Solid-State Sensors, Actuators and Microsystems (Transducers2009) 

    Presentation date: 2009

  • Micro Liquid Prism

    Yuta Yoshihata, Atsushi Takei, Nguen Binh-Khiem, Testuo Kan, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 22nd IEEE International Conference on Micro Electro Mechanical Systems (MEMS2009) 

    Presentation date: 2009

  • Solution Electrochemiluminescent Microfluidic Cell for Flexible and Stretchable Display

    Ryo Okumura, Seiichi Takamatsu, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 22nd IEEE International Conference on Micro Electro Mechanical Systems (MEMS2009) 

    Presentation date: 2009

  • Stretchable Substrates for the Measurement of Intracellular Calcium Ion Concentration Responding to Mechanical Stress

    Yun Jung Heo, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 22nd IEEE International Conference on Micro Electro Mechanical Systems (MEMS2009) 

    Presentation date: 2009

  • Integration of Bridging-Structural SWNTs on Flexible PDMS Sheet by Stamping Transfer

    Yusuke Takei, Eiji Iwase, Tetsuo Kan, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 22nd IEEE International Conference on Micro Electro Mechanical Systems (MEMS2009) 

    Presentation date: 2009

  • Temperature-Controlled Transfer and Self-Wiring for Multi-Color LED Display on a Flexible Substrate

    Eiji Iwase, Hiroaki Onoe, Akihito Nakai, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 22nd IEEE International Conference on Micro Electro Mechanical Systems (MEMS2009) 

    Presentation date: 2009

  • Hidden Vertical Comb-Drive Actuator on PDMS Fabricated by Parts-Transfer

    Eiji Iwase, Hiroaki Onoe, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 21st IEEE International Conference on Micro Electro Mechanical Systems (MEMS2008) 

    Presentation date: 2008

  • Liquid Motor Driven by Electrowetting

    Atsushi Takei, Nguyen Binh-Khiem, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 21st IEEE International Conference on Micro Electro Mechanical Systems (MEMS2008) 

    Presentation date: 2008

  • Batch Fabrication of Carbon Nanotube on AFM Probe Tips and AFM Imaging

    Kazuhiko Takagahara, Yusuke Takei, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 21st IEEE International Conference on Micro Electro Mechanical Systems (MEMS2008) 

    Presentation date: 2008

  • Air Flow Senser for an Insect-like Flapping Wing

    Hidetoshi Takahashi, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 21st IEEE International Conference on Micro Electro Mechanical Systems (MEMS2008) 

    Presentation date: 2008

  • Tapered Waveguide by Liquid for a Coupler of Optical Fibers to MEMS Devices

    Hisashi Terae, Nguyen Binh-Khiem, Tomoyuki Takahata, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 21st IEEE International Conference on Micro Electro Mechanical Systems (MEMS2008) 

    Presentation date: 2008

  • Scanning Micromirror using Deformation of a Parylene-Encapsulated Liquid Structure

    Yuta Yoshihata, Nguyen Binh-Khiem, Atsushi Takei, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 21st IEEE International Conference on Micro Electro Mechanical Systems (MEMS2008) 

    Presentation date: 2008

  • Stretchable Micropatterned Substrates using Pneumatic Actuators for Studying Mechanical-Stress-Dependent Cell Response

    Yun Jung. Heo, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 4th Asia-Pacific Conference on Transducers and Micro-Nano Technology (APCOT2008) 

    Presentation date: 2008

  • Flexible Tactile Sensor Sheet with Thin Si Piezoresistive Cantilevers Peeled off from SOI with PDMS Sheet

    Kentaro Noda, Hiroaki Onoe, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 4th Asia-Pacific Conference on Transducers and Micro-Nano Technology (APCOT2008) 

    Presentation date: 2008

  • Varifocal Infrared Imaging Lens by Parylene-on-Liquid-Deposition

    Hiroyuki Kojo, Nguyen Binh-Khiem, Tomoyuki Takahata, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 4th Asia-Pacific Conference on Transducers and Micro-Nano Technology (APCOT2008) 

    Presentation date: 2008

  • Floating Silicon Structure Supported by Carbon Nanotubes

    Kouichi Ishitaki, Yusuke Takei, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 4th Asia-Pacific Conference on Transducers and Micro-Nano Technology (APCOT2008) 

    Presentation date: 2008

  • Triaxial Tactile Sensor Chips with Piezoresistive Cantilevers Mountable on Curved Surface

    Yusuke Tanaka, Akihito Nakai, Eiji Iwase, Takanori Goto, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 4th Asia-Pacific Conference on Transducers and Micro-Nano Technology (APCOT2008) 

    Presentation date: 2008

  • Flexible Tactile Sensor Sheet with Thin Cantilevers for Shear Stress Detection on Curved Surface

    Kentaro Noda, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 17th CISM-IFToMM Symposium on Robot Design, Dynamics, and Control (RoManSy2008) 

    Presentation date: 2008

  • Stretchable Substrates using Pneumatic Actuators for Monitoring Mechanical-Stress-Dependent Cell Response

    Yun Jung Heo, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 12th International Conference on Miniaturized Systems for Chemistry and Life Sciences (microTAS2008) 

    Presentation date: 2008

  • 3D Integration of Heterogeneous MEMS Structures by Stamping Transfer

    Hiroaki Onoe, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 20th IEEE International Conference on Micro Electro Mechanical Systems (MEMS2007) 

    Presentation date: 2007

  • Electrically Driven Varifocal Micro Lens Fabricated by Deposition Parylene Directly on Liquid

    Binh-Khiem Nguyen, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 20th IEEE International Conference on Micro Electro Mechanical Systems (MEMS2007) 

    Presentation date: 2007

  • Electrochromic Voxel Array for 3D Display

    Sachio Murao, Seiichi Takamatsu, Binh-Khiem Nguyen, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 20th IEEE International Conference on Micro Electro Mechanical Systems (MEMS2007) 

    Presentation date: 2007

  • Thin Electrowetting Controlled Optical Systems with Pan/Tilt and Variable Focus Functions

    Atsushi Takei, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 14th International Conference on Solid-State Sensors, Actuators and Microsystems (Transducers2007) 

    Presentation date: 2007

  • Experimental Analysis of Liposome Water Two Phase Flow in Micro Channel for Localizing Reaction System using Liposome

    Yasumasa Ichikawa, Tetsuo Kan, Hiroaki Onoe, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 11th International Conference on Miniaturized Systems for Chemistry and Life Sciences (microTAS2007) 

    Presentation date: 2007

  • Angle Tunable Liquid Wedge Prism driven by Electro-Wetting

    Atsushi Takei, Eiji Iwase, Kazunori Hoshino, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 19th IEEE International Conference on Micro Electro Mechanical Systems (MEMS2006) 

    Presentation date: 2006.12

  • A Surface Plasmon Resonance Sensor With a V-shaped Silicon Prism Array

    Naoko Tsujiuchi, Eiji Iwase, Kazunori Hoshino, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 19th IEEE International Conference on Micro Electro Mechanical Systems (MEMS2006) 

    Presentation date: 2006.01

  • Angle Tunable Prism for Optical Scanner

    Atsushi Takei, Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 13th International Display Workshops (IDW2006) 

    Presentation date: 2006.01

  • Multi-Step Sequential Batch Self-Assembly of Three-Dimensional Micro-Structures using Magnetic Field

    Eiji Iwase, Isao Shimoyama

    Proceedings of the 18th IEEE International Conference on Micro Electro Mechanical Systems (MEMS2005) 

    Presentation date: 2005.01

  • "Pop-Up" Display with 3-Dimensional Microlens Structures

    Masakazu Tohara, Eiji Iwase, Kazunori Hoshino, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 18th IEEE International Conference on Micro Electro Mechanical Systems (MEMS2005) 

    Presentation date: 2005.01

  • The Structural-Color Based on the Mechanism of Butterfly Wing Coloring for Wide Viewing Angle Reflective Display

    Eiji Iwase, Kiyoshi Matsumoto, Isao Shimoyama

    Proceedings of the 17th IEEE International Conference on Micro Electro Mechanical Systems (MEMS2004) 

    Presentation date: 2004.01

  • Sequential Batch Assembly of 3-D Microstructures with Elastic Hinges by a Magnetic Field

    Eiji Iwase, Shoji Takeuchi, Isao Shimoyama

    Proceedings of the 15th IEEE International Conference on Micro Electro Mechanical Systems (MEMS2002) 

    Presentation date: 2002.01

  • Turning Gait Control of a Hexapod Robot

    岩瀬英治, 加藤慎一朗, 安田隆, 下山勲

    日本機械学会 ロボティクス・メカトロニクス講演会 

    Presentation date: 2000.05

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Specific Research

  • 折り畳みを利用した伸縮変形可能なシート型デバイス 

    2017  

     View Summary

    本申請課題の目的は、蛇腹折りやミウラ折りのような折り畳みを利用することで、伸縮変形や曲面への貼付けが可能なシートデバイスを実現することである。例えば、基板の中立面に電気配線を配置し、曲げ変形を受けない平板部に発光素子やセンサ素子を配置すれば、電気配線や発光素子・センサ素子に曲げ耐性・伸縮耐性がなかったとしても、デバイス全体としては伸縮耐性を有することができる。これにより、金属や半導体など、曲げ耐性・伸縮耐性を有しないが高性能・高機能な材料を用いて、伸縮変形可能なデバイスを実現することが可能となる。研究成果として、2次元の折り畳み方法の1つであるミウラ折りに切り込みを設けることで変形の自由度を増した構造による伸縮変形可能なLEDデバイスを実現した。

  • 少数電極駆動による多自由度MEMSスキャナ

    2014  

     View Summary

    本申請課題の目的は、支持梁の幾何形状を工夫することで各自由度に対する共振周波数を設計し、その構造を用いることで少数駆動電極による多自由度のMEMSスキャナの設計と実現可能性の検証を行うことである。3自由度(x軸回転、y軸回転、z軸回転)を有するMEMSスキャナを対象として、理論的に梁の設計を行うとともに有限要素法シミュレーションにより解析を行った。その結果、1対の梁によって、3自由度の共振周波数の離れた梁形状を設計することができた。さらに、マイクロファブリケーションを用いてMEMSスキャナの試作を行った。試作したMEMSスキャナの共振周波数特性を計測した結果、シミュレーションによる値と同等の特性を得ることができた。

  • 液体を用いた伸縮可能なMEMS配線

    2012  

     View Summary

     近年フレキシブルデバイスの研究が盛んになっているが、曲げのみならず伸縮に耐えられる配線材料はほとんどない。ゴム材料に導電性材料を混ぜた導電性ゴムの電気伝導率は10^1 S/m程度であり、これは固体の配線材料として用いられているAuが4.6×10^7 S/mであることと比べると非常に低い。そのため、高い伝導率と高い伸縮耐性とを兼ね備えた電気配線が求められている。 そこで、本研究では液体を利用することによる曲げられかつ伸縮可能な電気配線を目的とした。柔軟基板上に金属の配線部とそれを覆うように液体を配置した構造を基本とし、MEMS(Micro-Electro-Mechanical Systems)の加工技術により製作する。金属としてはAuを、柔軟基板としてはシリコーンゴムの一種であるPDMS(polydimethylsiloxane)を用いた。液体としては、イオン液体を用いることとした。その理由としては、高いイオン伝導率を持つことに加え、水に比べ広い電位窓をもつため電気的に利用しやすいこと、化学的安定性が高いことが挙げられる。しかしながら、未硬化のPDMSをイオン液体と接した状態で硬化させようとすると硬化阻害が起こり、PDMSが硬化しないという問題が発生した。10 hPa程度の低真空でCVD(Chemical Vapor Deposition: 化学的気相堆積)が可能なパリレンは、シリコーンオイルやグリセリンのような低蒸気圧の液体上に直接成膜することができることが知られている。イオン液体もまた低蒸気圧の液体であるため、イオン液体をパリレン膜で封止した後に未硬化のPDMSを流し込み柔軟基板への埋め込みを行った。 伸縮配線を抑える治具と計測用の電極端子が直動ステージに取り付けられた計測セットアップを用いて歪みに対する伝導率の変化の計測を行った。その結果、歪みが0 %での電気伝導率が8.1×10^6 S/mであったのに対して、歪みが24 %のときにでも2.5×10^6 S/mと10^6オーダの電気伝導率が得られた。

 

Syllabus

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Committee Memberships

  • 2018.08
    -
    Now

    文部科学省 研究振興局  学術調査官

  • 2018.08
    -
    Now

    (一社)電気学会 センサ・マイクロマシン部門  MSS技術委員会,委員

  • 2018.08
    -
    Now

    (一社)日本機械学会 若手の会  委員

  • 2018.04
    -
    Now

    (一社)日本機械学会 情報・知能・精密工学部門  編集委員会,幹事

  • 2018.04
    -
    Now

    (一社)日本機械学会 情報・知能・精密工学部門  運営委員会,委員

  • 2014.04
    -
    Now

    (一社)日本機械学会 マイクロナノ工学部門  運営委員会,委員

  • 2010.06
    -
    Now

    (公財)数学オリンピック財団  評議員

  • 2005.04
    -
    Now

    (公財)数学オリンピック財団  国際数学オリンピック日本委員会(JCIMO),委員(2005年4月1日-現在),常任委員(2009年4月1日-現在)

  • 2017.10
    -
    2018.09

    (一社)日本機械学会 広報・情報部会  委員

  • 2017.10
    -
    2018.09

    (一社)日本機械学会 広報・情報部会  機械工学事典電子版WG,委員

  • 2016.04
    -
    2018.03

    (一社)日本機械学会 マイクロナノ工学部門  総務委員会,委員

  • 2012.04
    -
    2018.03

    (一社)日本機械学会 マイクロナノ工学部門  広報委員会,委員(2012年4月-2018年3月),幹事(2015年4月-2016年3月),委員長(2016年4月-2018年3月)

  • 2008.11
    -
    2010.10

    (一社)電気学会 センサ・マイクロマシン部門  電気等価回路を用いたMEMS設計手法調査専門委員会(EMSS1021),委員

  • 2007.06
    -
    2009.03

    (独)新エネルギー・産業技術総合開発機構(NEDO)  高集積・複合MEMS製造技術開発事業,ファインMEMSシステム設計プラットフォーム検討委員会,委員

  • 2006.09
    -
    2009.03

    (独)新エネルギー・産業技術総合開発機構(NEDO)  高集積・複合MEMS製造技術開発事業,ファインMEMS知識データベース委員会,委員

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