Thermal design and analysis of high power SiC module with low profile and enhanced thermal performance

In this study, a silicon carbide (SiC) device based power module with low profile and enhanced thermal performance is explored. The low profile is achieved by embedded the SiC chips into the direct bonded copper (DBC) substrate which is designed with cavities. The enhanced thermal performance is achieved by eliminating the core layer of the DBC substrate and shortening the thermal path from the SiC Chip (heat source) to the cold plate (heat sink). Furthermore, a flat surface on the top side of the power module is achieved by designing and positioning the top copper clips in the same level as the top copper trace of the DBC substrate. As such a second liquid cooled cold plate can be implemented on the top surface of the module to further enhance the thermal performance of the power module through the dual side liquid cooling solution. The simulation results show that the chip junction to case thermal resistance for the proposed power module is about 50∼60% of the chip junction to case thermal resistance for the conventional power module with similar size and power rates. By applying double side liquid cooling to the proposed power module which is not adaptable for the conventional power module, the thermal performance of the proposed power module further increased about 20%.