Development of an Innovative Active Cooling System for High Heat Flux Electronics

Many military electronic applications require cooling that is beyond the capabilities of both passive and active conventional cooling techniques. A need exists for cooling technologies that can reach and exceed 1000 W/cm2. Recently, direct spray coolinghas been investigated as a means to remove high heat fluxes from electronic chips. In this approach the coolant, water or dielectric fluid, directly impinges upon the surface of the electronic chips and rapidly vaporizes to remove heat. However, directspray cooling of a chip has severe disadvantages. In this program we will investigate a novel approach to electronic chip cooling that will allow heat flux removal rates of 1000W/cm2 and beyond, using a system that is easier to implement and lesscomplicated than direct spray cooling of the chip surface. Spray cooling will be accomplished on the backside of an advanced heat spreader in a completely self contained system that is separate from the electronics, which will be relatively simple toattach to an electronic chip. A high performance thermal interface material will be utilized to minimize the interface resistance between the advanced cooling system and heat generating chip. The cooling system concepts developed in this program may beuseful for numerous military and commercial packaging applications where devices are thermally constrained, and conventional cooling techniques are inadequate. Potential applications include radar T/R modules, power conditioning electronics, commercial andmilitary hybrid electric vehicles, high power laser diodes, and military pulsed power systems.