A High-Performance Embedded SiC Power Module Based on a DBC-Stacked Hybrid Packaging Structure

Abstract

Silicon carbide (SiC) devices have the advantage of high switching speed. However, the switching speed is limited by the high parasitic inductance which could cause high voltage overshoot, parasitic turn-on, oscillation, and electromagnetic interference (EMI) issues. Thus, the parasitic inductance of the SiC power module has to be reduced for better performance. This paper proposed an integrated half-bridge (HB) power module based on a direct bonding copper (DBC)-stacked hybrid packaging structure. This packaging structure utilizes two DBC substrates to stack together, which form a 3-D power commutation loop. The SiC chips are embedded on the top of the bottom DBC substrate to reduce the thermal resistance. Based on an optimized mutual inductance cancellation design, the proposed DBC-stacked hybrid packaging structure has only 1.8-nH commutation power loop inductance for a 1200-V, 120-A HB power module. Moreover, the geometrical parameters of the laminated power terminal have been analyzed and optimized for the symmetrical current sharing in the multichip paralleled power module. A compact 1200-V, 120-A full SiC HB power module with integrated decoupling capacitors has been fabricated and the dc-link capacitor board, gate drivers can be integrated on the power module compactly. Finally, the static and dynamic characteristics of the proposed module have been tested. The results of double pulse test (DPT) under zero external driver resistor indicate that the voltage overshoot of the proposed module is reduced by approximately 55% compared to the commercial power module, and the total switching energy is only 43% of the commercial module. Moreover, the loss of the 5.5-kW single-phase inverter based on the proposed module is reduced by 28.3% compared with the inverter based on the commercial module under 120-kHz switching frequency.