Power cycling lifetime model of sliver sintered SiC MOSFET power module based on physics-of-failure approach

Inhalt:
With the application of new packaging materials such as sintered silver in SiC modules, the high reliability characteristics poses new challenges to the product reliability evaluation, especially the lifetime modeling. Traditional modeling methods have problems such as time consumption and poor reusability, and the physics-of-failure methodology is used in this paper to infer fast lifetime prediction in early design stages. Firstly, a liquid-to-liquid thermal shock test was used to conduct an accelerated fatigue test, and the degradation of the sintered layer is quantitatively characterized through SAM images, then the fatigue model parameters are inverted combining finite element (FE) simulation and experiments. Finally, the electrical-thermal-mechanical FE model of the power module is established to simulate different power cycling conditions, and a lifetime model is established based on the predicted lifetime. The research methods and results can provide guidance for lifetime modeling and reliability forward design of power modules.