Manufacturing and Characterization of a Thermoelectric Energy Harvester Using the CMOS-MEMS Technology

The fabrication and characterization of a thermoelectric energy harvester using the complementary metal oxide semiconductor (CMOS)-microelectromechanical system (MEMS) technology were presented. The thermoelectric energy harvester is composed of eight circular energy harvesting cells, and each cell consists of 25 thermocouples in series. The thermocouples are made of p-type and n-type polysilicons. The output power of the energy harvester relies on the number of the thermocouples. In order to enhance the output power, the energy harvester increases the thermocouple number per area. The energy harvester requires a post-CMOS process to etch the sacrificial silicon dioxide layer and the silicon substrate to release the suspended structures of hot part. The experimental results show that the energy harvester has an output voltage per area of 0.178 mV ̈mm ́2 ̈K ́1 and a power factor of 1.47 ˆ 10 ́3 pW ̈mm ́2 ̈K ́2.