Energy efficient liquid-thermoelectric hybrid cooling for hot-spot removal

We report a study on a liquid-thermoelectric hybrid cooling that allows a multiple larger heat flux (>;600 W/m²) hotspots on a chip that is never achievable with a reasonable pump power for a microchannel with single phase liquid cooling. Thermoelectric effect is realized in this study by embedding to the silicon chip in superlattice microcooler which has been studied in our previous work. We went through an analytic modeling including spreading resistance through the substrate and modeled the fluid dynamic characteristic of microchannel so that we were able to find the pump power and cooling power of superlattice cooler. We also verified the performance with 3D numerical simulation. The results show that the hybrid system allows much higher heat flux for a hotspot while superlattice cooler locates correctly. As an example, if we have a ZT=0.5 material, a 500μm × 500μm hotspot can be maintained at 85°C (ambient 35°C) with around 850W/cm² while a simple liquid cooling reaches 620W/cm² for the same 12W/cm² of overall cooling power.