Cross-Linked Microchannels for VLSI Hotspot Cooling

Thermal management for the future generations of electronics faces challenges including total heat dissipations exceeding 100 W and local hotspots resulting from non-uniform heating. This work develops microchannel heat sinks with cross-linked channels to achieve a better chip temperature uniformity under non-uniform heating conditions. Stream-wise microchannels with a hydraulic diameter of 420 μm are subjected to pressure driven water flow. Channel cross-links with a hydraulic diameter of 150 μm, under non-uniform heating conditions, allow fluid lateral transport between the stream-wise channels in the region receiving the largest heat flux and those on the rest of the chip. As a result, a better chip temperature uniformity is achieved by utilizing the local pressure difference and capillary effect. Experimental results with a localized heating condition demonstrate an improvement of approximately 10% in the ratio of temperature of the heater to that of the rest of the chip. Analysis suggests that greater improvement can be achieved through optimization of the dimensions of the cross-links with respect to those of the stream-wise channels and through tailoring more cross-links within the hotspot region.