Design and Investigation of MEMS-Based Thermopile Detector Arrays for Infrared Sensing Applications

This research paper focuses on the design and optimization of MEMS-based thermopile arrays for infrared (IR) sensor applications. Thermopiles, constructed using materials such as bismuth telluride and polysilicon, exhibit the Seebeck effect, generating voltage in response to temperature differences. We explore the optimization of thermocouple configurations to enhance output voltage and sensitivity to IR radiation. The study involves single-layer, double-layer, and stacked double-layer thermocouple designs. Finite element analysis is employed for modeling and analysis, considering material properties and layer thicknesses. Comparative analyses between polysilicon and bismuth telluride thermocouples are presented for horizontal array configurations. The results acquired indicate that stacked double-layer thermocouples produce the highest output voltage, achieving optimal minimum thickness for ${SiO}_{2}$ and the thermocouple strip. Bismuth telluride, possessing a higher figure of merit, surpasses polysilicon due to its superior thermoelectric properties.