A New Reliability Assessment Model for Power Electronic Modules Considering Failure Mechanism Interaction

Abstract

A reliability prediction method is proposed to determine the lifetime of IGBTs (Insulated Gate Bipolar Transistors) under power cycling test based on the performance of solder joint and wire bond. The failure characteristics of solder joint and wire bond are captured via selected PoF model respectively. To provide precise reliability prediction, PoF models are converted into probabilistic models. In addition, the failure interaction between wire bond and solder joint is studied. Wire bond lift-off is treated as the predominant failure mode based upon experiments from literature and solder joint degradation process is triggered by wire bond degradation process. Increased junction temperature is captured as it is affected by the degradation process of both components. In the end, the system reliability is computed in a series system configuration.