Failure initiation of IGBT due to emitter contact degradation: A 2D finite elements electro-thermal multi-cell simulation approach under hard switching, short-circuit and avalanche operations

This paper reports, for the first time, the internal physics of IGBT under severe switching conditions based on 2D finite elements multi-cell device simulation pointing out the advantages of such approach particularly in the case of a packaging degradation due to wire-bonding lift-off or top metallization ageing. The results show that the multi-cell simulation highlights intercellular electro-thermal phenomena which may lead the IGBT into failure. A full internal analysis allows to focus on the main internal physics parameters and to provide useful information on the device failure initiation and interesting issue to increase the device robustness for devices designers.