Prospects of Thin-Film Thermoelectric Devices for Hot-Spot Cooling and On-Chip Energy Harvesting

Advances in thin-film thermoelectric (TE) materials have created opportunities for using TE devices in high heat flux applications such as hot-spot (H-S) cooling and on-chip energy harvesting. In this paper, we compare the performance of TE modules integrated directly on the silicon die with those that are attached to the heat spreader of the chip package. We make use of the Bi₂Te₃/Sb₂Te₃ super lattice material to explore tradeoffs between the two integration options for H-S cooling and energy-harvesting applications. Package level finite element simulations show that on-chip energy harvesting can yield up to 30 mW of power from an H-S with a heat flux of 200 W/cm², or the same H-S can be cooled as much as 19°C in the cooling mode. In addition, the TE module integrated on the die is shown to have a disadvantage due to the higher thermal resistance from the hot side of the module to the ambient.