Study of RBSOA reliability of nanoscale Partially Narrow Mesa IGBT (PNM-IGBT)

In this paper, the RBSOA characteristic of nanoscale Partially Narrow Mesa IGBT (PNM-IGBT) is studied by numerical simulation. Result shows that the maximum turn-off critical current of nanoscale PNM-IGBT increases about 12.3% compared with the conventional trench IGBT. The main reason is that the electric field distribution of PNM-IGBT at turn-off state is more flat and uniform than the conventional trench IGBT. Thus, local carrier concentration is attenuated and the happening chance of the dynamic avalanche effect is less. Furthermore, the location of the peak electric field is shifted to the center of mesa area and the hole below the Nplus area is reduced correspondingly. Therefore, the turn-off ruggedness of this PNM-IGBT becomes much better compared with the conventional trench IGBT.