Miniaturized in-plane π-type thermoelectric device composed of a II–IV semiconductor thin film prepared by microfabrication

A miniaturized in-plane π-type thermoelectric device based on an epitaxial thin film of the II–IV compound thermoelectric semiconductor Mg2Sn0.8Ge0.2 was developed utilizing the microfabrication techniques of photolithography and dry etching. Highly reliable thermoelectric device operation was successfully achieved. The microfabricated thermoelectric device generated a relatively high output voltage of 0.58 V and an output power of 0.6 μW, corresponding to a comparatively high output power density of 21 mW·cm−2. The successful demonstration of a microfabricated thin-film-based thermoelectric device paves the way toward novel thermoelectric applications for self-powered Internet of Things devices and systems, as well as applications involving the effective use of the waste thermal energy generated from high heat density during the operation of electronic devices and systems.