This research focuses on the development of a high-performance, large-scale integrated micro-thermoelectric generator (μ-TEG) utilizing advanced materials and CMOS-compatible fabrication techniques. The primary aim is to enhance the thermoelectric (TE) performance and scalability of μ-TEGs for practical applications such as IoT sensor nodes, wearable devices, and waste heat recovery systems.Initial work by our group on silicon-based thermoelectric devices has demonstrated promising heat flux sensitivity and TE performance. Building on this foundation, the current research introduces Germanium Tin (GeSn), a high-performance TE material with superior conversion efficiency compared to conventional silicon. GeSn integration is expected to significantly boost energy conversion and output voltage.To overcome the limitations of traditional single-stage TEGs—which typically suffer from low output voltage and efficiency—this work emphasizes the integration of multiple stages within a single device. This approach enables cumulative voltage generation and improved energy harvesting capabilities. The μ-TEG will be fabricated on Gallium Arsenide (GaAs) substrates, where the GeSn layer will be patterned into thermoelectric elements using photolithography and reactive ion etching. Metal contacts (TiN/AlCu/TiN/Ti) will be deposited via sputtering to form efficient electrical pathways. A micro-heater and Peltier cooler will be employed to generate the required temperature gradient across the device.The research also addresses key challenges such as optimization of the metal/semiconductor contact layout and wiring architecture to minimize losses and maximize output. Successful integration of GeSn in the CMOS process ensures high-density device fabrication, cost-efficiency, and compatibility with existing semiconductor technologies.The significance of this research is underscored by recent publications and conference presentations that explore thermal characterization, contact layout effects, wiring optimization, and sensitivity analysis of integrated TE devices. These include studies published in Japanese Journal of Applied Physics and Microelectronic Engineering (under review), and presentations at SSDM 2024, JSAP, and DEJl2MA2024.Ultimately, this project aims to deliver a scalable, cost-effective, and energy-efficient μ-TEG platform, pushing the frontiers of self-powered microelectronics and sustainable energy harvesting.