The effect of a shielding layer on breakdown voltage in a trench gate IGBT

In this paper we introduced the shielding layer concept in order to alleviate the electric field of concentrated on the trench bottom corner. The shielded trench gate IGBT is a trench gate IGBT with a P+ shielding layer bottom of a trench gate. By simulation results, we verified that a shielding layer reduced the electric fields not only in the gate oxide but in the p-base region. Compared with conventional trench gate IGBT, about 33% increment of forward breakdown voltages are achieved.