Physics-of-Failure Based Lifetime Approach for Silver Sintered Power Modules in Power Cycling

New reliability requirements for power modules due to increasing demands, new materials and new technologies render classical empirical lifetime models not sufficient anymore. The paradigm change towards a physics-of-failure framework for lifetime modeling within power electronics offers the possibility to connect stress tests, microstructural analysis and finite element simulations. Especially, power cycling plays a crucial role as reliability test of power modules as it features the most application-like conditions with the semiconductor serving as heat source. To successfully model this stress test multidomain simulations are needed which comprise electro-thermal and thermo-mechanical setups. In this study, power cycling experiments with three different testing conditions are performed and followed by an in-detail microstructural analysis. Multidomain FE simulations accompany the experiments to determine the failure mechanisms and are used to generate the lifetime model.