A multistage in-plane micro-thermoelectric cooler

This paper presents a mutli-stage thermoelectric micro cooler designed for integration with a wide variety of MEMS devices, including MEMS resonators, which benefit from decreased phase noise at low temperatures. The cooler is fabricated using a multilayer process that allows the device to achieve thermal isolation greater than 10,000 K/W while still maintaining mechanical robustness for practical applications. Co-evaporated thin film bismuth telluride and antimony telluride are used as the thermoelectric materials. The cooler is 9 x 9 mm² and a preliminary prototype has achieved cooling of 3.8 K, comparable to values predicted using a one-dimensional mathematical model.