Thermal simulation and optimization of a SiC power module based on graphite-embedded structure
Compared to silicon, SiC devices have higher power density and exhibit higher device junction temperature and thermal resistance. To enhance its thermal dissipation capability, a packaging structure of SiC power module was proposed based on graphite-embedded layered DBC, whose packaging model was also established. The graphite layer thickness, copper layer thickness and thermal conductive copper column diameter were analyzed with ANSYS software to understand their effects on the heat dissipation performance, and the packaging structure was optimized to obtain better thermal performance. The simulation results show that the junction temperature of the graphite embedded packaging structure is 61. 675℃, which is reduced by 19. 32% from traditional single-layer DBC packaging with thermal resistance decreased by 27. 05%. Among the influential factors, the graphite layer thickness has the most significant impact on the packaging junction temperature and thermal resistance. Copper pillar diameter and copper layer thickness are the second and the third influential factors respectively. After optimization, the junction temperature is reduced by 2. 1%, and the thermal resistance decreases by 3.4%. Therefore, the packaging structure could achieve excellent thermal performance and provides a reference for the application of high thermal conductivity graphite in the thermal management of power modules.
SiC power modulegraphitepackagingthermal simulationstructure optimization