Embedded Cooling of High-Heat-Flux Hotspots Using Self-Adaptive Microchannel/Pin-Fin Hybrid Heat Sink

Abstract

The chips present unsteady and highly concentrated heat fluxes and the available volume for cooling solution is significantly constrained with the trend of miniaturization and integration. Traditional liquid cooling techniques fail to regulate the coolant distribution according to the changing thermal environment and remove the unevenly distributed thermal loads effectively. In this article, embedded cooling with self-adaptive microchannel/pin-fin hybrid heat sink is proposed. Hybrid channels with thermal-sensitive hydrogels at the outlet are designed and integrated into the substrate. A numerical model is established and an iteration procedure is designed to investigate the flow regulation behavior. The hydrogel downstream of the hotspot undergoes volume reduction and the local coolant flow rate is enlarged, illustrating the autonomous flow regulation effect. Various nonuniform heat load distributions are considered. Taking advantage of the current self-adaptive cooling solution, heat flux of up to 500 W/cm2 can be dissipated and the peak temperature is reduced by 12.2 K with a pressure drop of 34.0 kPa. The embedded self-adaptive cooling provides both effective and intelligent thermal management for densely integrated electronics.