FE analysis the effect of bonding wire and solder failure on the resistance and temperature of IGBT

As the demand of power module in higher power density occasion is increasing, bonding wire and solder failure of insulated gate bipolar transistor (IGBT) becomes more severe. Accordingly, it is of great significance to quantify the contribution of these two different failure modes on the overall module degradation. In this paper, the finite element (FE) modes of different bonding wire quantity and solder void area have been established. The resistance variation of these models has been calculated and compared. Furthermore, basing on the relationship of resistance and saturation voltage (V_ce), the degradation degree of two failure modes has been evaluation. Meanwhile, the effect of failure ratio of bonding wire and solder on temperature has been measured and analyzed. Results show that solder void has a greater impact on module failure than bonding wire lift off. When the lift off ratio of bonding wire is 44%, Vce only increases by 3.5% and the module has not failure. Nevertheless, when the void area ratio of solder is 22%, V_ce increases by 38.7%, which has cause the module failure. This results not only provide a simple method to evaluate the electrical and thermal properties of IGBT module. It also establishes a foundation for distinguishing the impact of different failure modes on the degradation degree of the overall module.