Thermoelectric generator

Electrical engineering

Physics

Infrared

CMOS

Optics

Engineering

Thermocouple

Composite material

Microelectronics

Materials science

Integrated circuit

Silicon

Thermopile

Optoelectronics

Thermoelectric effect

Thermodynamics

Nature Electronics

Microelectronic thermoelectric generators (TEGs), which can recycle waste heat into electrical power, have applications ranging from the on-chip thermal management of integrated circuits to environmental energy sources for Internet-of-things sensors. However, the incompatibility of TEGs with silicon integrated circuit technology has prevented their broad adoption in microelectronics. Here, we report TEGs created using nanostructured silicon thermopiles fabricated on an industrial silicon complementary metal–oxide–semiconductor (CMOS) process line. These TEGs exhibit a high specific power generation capacity (up to 29 μW cm−2 K−2) near room temperature, which is competitive with typical (Bi,Sb)2(Se,Te)3-based TEGs. The high power capacity results from the ability of CMOS processing to fabricate a very high areal density of thermocouples with low packing fraction and to carefully control electrical and thermal impedances. TEG power was also found to increase significantly when thermocouple width was decreased, providing a path to further improvements. Unlike (Bi,Sb)2(Se,Te)3 TEGs, our silicon integrated circuit TEGs could be seamlessly integrated into large-scale silicon CMOS microelectronic circuits at very low marginal cost. Thermoelectric generators based on nanostructured silicon thermopiles, which are fabricated on an industrial silicon CMOS process line and are thus compatible with integrated circuit technology, exhibit a high specific power generation capacity of up to 29 μW cm−2 K−2 near room temperature.

Silicon integrated circuit thermoelectric generators with a high specific power generation capacity