TCAD Simulation Modeling of Mold Epoxy Resin Applied for Encapsulation of Power Devices

The impact of carrier injection into mold epoxy resin on the device leakage current of power modules is investigated by our proposed model of the resin and its application to a simplified power module. Charge redistribution or polarization of the resin alters the surface potential of the edge termination region, leading to electric failure during reliability tests such as High- Temperature Reverse Bias test. While attempts to simulate such behavior have been reported, the modeling of the epoxy resin and its interaction with the device termination and bonding wires are not fully understood. This paper shed light on this issue by presenting a physically reasonable assumption that can help resolve it.