Package-Level Integration of Liquid Cooling Technology with Microchannel IHS for High Power Cooling

Liquid cooling using an integrated microscale heat exchanger is a promising future technology option to address issues associated with integrated circuit thermal management. A new class of liquid cooling technology that involves package-level integration for enhanced stack-up thermal resistance, thus providing superior thermal performance compared to the state-of-the-art air- or liquid-cooled solutions across a broad range of package applications, is described in this paper. This innovative, liquid cooling technology concept called Micro-Channel IHS (i.e., MC-IHS (Integrated Heat Spreader)) involves introducing internal liquid-flow microchannels into the IHS lid in the package, such that IHS effectively becomes an integrated "cold-block" and eliminates the TIM interface between cold plate and IHS. MC-IHS prototypes, which emulate high-end XPU device were built on a TTV to characterize thermal performance. Thermal test results showed that MC-IHS technology can provide ~30% superior cooling capability over a standard cold plate and can reach performance of Rf-in of ~0.05 °C/W with >1,000 W cooling capability. New class of future XPU products can take advantage of this cooling capability to significantly improve computing performance.