Simulation of Space Charge Behavior in Silicone Gel Above Edge Termination Area of Power Chip

In recent years, IGBT modules have been required to ensure high reliability under severe environment with high temperature and high humidity. During the reliability test, space charge injected from electrodes accumulates in the encapsulating resin above edge termination of IGBT chips. Then, the space charge distorts the electric field distribution inside the chips, potentially could lead to failures such as increase of leakage current. Therefore, it is important to understand the space charge distribution in resin for more reliable IGBT design. In this study, we investigated the space charge distribution of the silicone gel on the high voltage IGBT chip using TCAD simulation and discussed its effects on electrical properties of the device.