Development of Quantum Well Thermocouples in Thermoelectric Energy Harvesters

S.M. Yang
National Cheng Kung University,
Taiwan

Keywords: smart energy, thermoelectric energy harvester, CMOS device

Summary:

CMOS (Complementary Metal Oxide Semiconductor) process by using pand n-type field effect transistors has been available for microprocessors and microsensors. With the advent of foundry services in IC industry over the past two decades, standard CMOS/BiCMOS process have been considered the perfect platform for semiconductor thermoelectric energy generator (TEGs). Many TEG designs have therefore adopted the mature, reliable, and high yield process, where the polysilicon layers facilitate high integration density of thermocouples on a wafer. This work aims at summarizing the progress of semiconductor TEGs from tailored MEMS process to commercially available standard CMOS/BiCMOS process. By comparing the reports in the open literature, semiconductor TEGs are shown to achieve performance competitive to present mainstream BiTe-based TEGs. The performance of a semiconductor TEG can be improved by exploiting configuration design, thermocouple dimension and materials properties in modern silicon processing technology. State-ofthe-art semiconductor TEGs have been shown to achieve power factor about 10-1~10-2 μW/cm2K2 and voltage factor 10~100 V/cm2K.