Simulation and Analysis of CMOS Based Micro Thermoelectric Power Generator

Abstract

This paper presents a Complementary Metal Oxide Semiconductor (CMOS) based Thermoelectric Power Generator (TPG) to harvest unused heat and convert it to usable electrical current. Detailed simulation and analysis of various model has been shown for thermoelectric power generator (TPG) to achieve improved performance. Thermal analysis using the ANSYS software has been done for various models to show the increase in output current of the thermocouple. Different techniques like change in heat sink material, formation of cavities, change in contact materials, change in thermocouple length and width to improve the temperature difference between hot and cold junction and the output current. Comparison has been made for different devices by changing parameters to select the best model to deliver more electrical current. Large Seebeck effects are found in doped Poly-Silicon, which makes it a suitable choice for CMOS based thermoelectric devices. Thin film of poly-Si is deposited and patterned to form thermocouples, and an array of thermocouples, i.e., a thermopile, could be arranged in a tiny area. For a device in the size of $500\mu \text{m}^{2}$ with effective length (L) of each thermocouple is $5\ \mu \text{m}$, an output current of O.4mA is obtained with a 5K temperature difference across two sides.