Thermal Analysis, Characterization and and Material Selection for SiC Device Based Intelligent Power Module (IPM)

In this paper, a silicon carbide chip based dual side liquid cooling power module with integrated temperature sensors is designed. The designed power module has footprint of 40mm x 40mm. The major components of the designed power module include the silicon carbide dies and thin film type thermistor chips. To develop this new generation power module, the approach combining the thermal performance analysis, packaging material selection, cooling plate optimization and test sample realization is implemented. At first, a thermal model is constructed and the thermal simulation is performed to simulate the thermal characteristic of the proposed IPM. Effect of different packaging materials on the power module thermal resistance is investigated and analyzed. A group of materials which produce the lowest thermal resistance is recommended for the proposed SiC chip based IPM. Then the IPM sample is manufactured with the recommended materials. Furthermore, the liquid cooling cold plates with jet impingement technology and optimized parameters are designed and fabricated. Finally, the test samples for thermal performance characterization is assembled. The simulation results indicate that the thermal interface material (TIM) imposes the most remarkable effects to the thermal resistance of the proposed IPM, while the effect of the other packaging materials, such as die attach (DA), epoxy molding compound (MC) and interconnect joint material (JM), on the thermal resistance of the proposed IPM are insignificant. Meanwhile, nozzle length, jet to wall distance and flow channel width are critical parameters to be optimized for the cooling performance of the liquid cooling plate.