High Efficiency Polymer based Direct Multi-jet Impingement Cooling Solution for High Power Devices

A high efficiency 3D-shaped polymer multi-jet impingement cooler based on cost efficient fabrication techniques is introduced for the cooling of high power applications. State of the art highly efficient multi-jet cooling solutions rely on expensive Si or ceramic fabrication techniques, while low cost cooling solutions have been proposed for less performant single jet impingement. In this paper, we present the concept, modeling, design, fabrication, experimental characterization and benchmarking with literature data of a multi-jet impingement based liquid cooling solution, fabricated using low cost polymer fabrication techniques, targeted to directly cool the backside of high power devices. For the modeling study, unit cell model and full system level models are used to study the nozzle array scaling trends and thermal and fluidic the jet-to-jet interactions. Furthermore, design guidelines for high power electronics cooling are provided, including geometry selections, material selection, and fabrication techniques. Based on the design guidelines and cooling concept, this paper demonstrates a 3D-shaped polymer impingement cooler with a 4× nozzle array, showing a very good thermal performance with low required pumping power. The multi-jet cooler can achieve heat transfer coefficients up to 6.25×104 W/m 2 .K with a pump power as low as 0.3 W. The benchmarking study confirms furthermore that multi-jet cooling is more efficient than single jet cooling and that direct cooling on the backside of the semiconductor device is more efficient than cooling the substrate or base plate.status: publishe