Integrated Reduced-Expansion Microchannel Cooling for SiC Power Modules

High power semiconductor devices suffer from difficulty in dissipating heat and thermal stresses. Silicon carbide-based power modules, in particular, have increasingly challenging heat loads despite their high efficiencies. In general terms, the module packaging methods used to improve cooling (moving metal heatsinks closer to the die) also increase thermal stresses, and the methods used to reduce stresses (introducing ceramics or compliant bonds between the heatsink and the die) make cooling more difficult.   In the proposed effort, microchannel cooling passages will be introduced into a reduced thermal expansion metal such as molybdenum/copper, and this cooling system will be packaged as the baseplate of existing silicon carbide power modules. This reduces thermal stresses and improves thermal performance compared to conventional methods, resulting in a package capable of dissipating more than 500 W/cm2.   The Phase I will optimize the microchannel and flow distribution designs, build prototypes, and begin development of a silicon carbide power module suitable for testing at high heat fluxes in Phase II. The Phase I Option will evaluate the prototypes and finalize the design and fabrication plan for the power module to be built in Phase II.