Through-chip microchannels for three-dimensional integrated circuits cooling

Abstract: Cooling high-power electronics in multilayer integrated circuits (ICs) is challenging for existing cooling methods. In this work, we designed through-chip microchannels (TCMCs) that cross the entire chip perpendicularly to the layers, with water circulating inside to provide direct cooling to each layer. TCMCs are organized in a square array where the pitch and radius of the microchannels are explored. Our computational fluid dynamics (CFD) simulations show that a pitch 10 {\mu}m and a radius 1 {\mu}m optimize the cooling performance to support a power higher than 10^4 W/cm2 while the maximum temperature rise remains below 60 K with a water inlet temperature of 300 K. We show that the cooling properties do not change with the number of layers for a given chip thickness which provides flexibility to the functional design of the chip. Though manufacturing may be challenging, TCMCs offer a new way for chip cooling that could provide a leap forward in the performance of multilayer 3D ICs and high-power electronics.