Flexible thermoelectric generator for ambient assisted living wearable biometric sensors

摘要

In this work we proposed design, fabrication and functional characterization of a very low cost energy autonomous, maintenance free, flexible and wearable micro thermoelectric generator (μTEG), finalized to power very low consumption electronics ambient assisted living (AAL) applications. The prototype, integrating an array of 100 thin films thermocouples of Sb_2Te_3 and Bi_2Te_3, generates, at 40℃, an open circuit output voltage of 430 mV and an electrical output power up to 32 nW with matched load. In real operation conditions of prototype, which are believed to be very close to a thermal gradient of 15℃, the device generates an open circuit output voltage of about 160mV, with an electrical output power up to 4.18nW. In the first part of work, deposition investigation Sb_2Te_3 and Bi_2Te_3 thin films alloys on Kapton HN polyimide foil by RF magnetron co-sputtering technique is discussed. Deposition parameters have been optimized to gain perfect stoichiometric ratio and high thermoelectric power factor; fabricated thermo-generator has been tested at low gradient conditioned to evaluate applications like human skin wearable power generator for ambient assisted living applications.