A Novel Packaging Method Using Flexible Printed Circuit Board for High-Frequency SiC Power Module

In this paper, a novel packaging method which features wirebond-less structure by using flexible printed circuit board (FPCB) are presented. Detailed comparisons are also conducted with the wirebonding hybrid packaging structure in a half-bridge (HB) module. The results reveal the better performances of the FPCB packaging method in smaller parasitic inductances, less switching losses, better thermal stability. Compared with the wirebonding packaging structure, the parasitic inductances in power loop and gate loop decrease by 52% and 76% respectively. The double pulse test (DPT) was established in simulation to compare the switching losses which decreases by 22% relatively. Furthermore, the simulation is conducted by Finite Element Analysis (FEA), and the temperature of the FPCB structure decreases by 20°C. This paper also focuses on the reliability of solder layer between FPCB and DBC substrate. In general, it clearly manifests that, the FPCB packaging structure has smaller parasitic inductances, better thermal performance and reliability.