Drift Region Integrated Microchannels for Direct Cooling of Power Electronic Devices: Advantages and Limitations

Direct liquid microchannel cooling is of great interest when considering the thermal management of high-heat flux power devices and modules. This paper presents an original concept for efficient cooling of power devices based on the integration of a microchannel cooler, including numerous parallel through wafer fluid vias, directly into the drift region of the vertical power device and perpendicular to the PN junction of the device. Simulation results proved that no negative side effects are resulting from this integration regarding the electrical performance of the device. Electrical tests were carried out to validate the functionality of the fabricated prototypes. The effectiveness of the proposed cooling technique was evaluated with hydraulic and thermal numerical models. In line with the design of the device and the microchannel cooler analysis, an experimental setup for the measurement of the thermal and hydraulic performances of the concept was realized. Pressure drops were measured and compared with the theoretical results.