Low on-state losses trench IGBT with high-k dielectric layer

A novel trench IGBT with a high-k (HK) buried layer below the trench gate is proposed and investigated by simulation. The HK dielectric causes a self-adapted assistant depletion of the n enhancement layer. This not only increases the n enhancement layer doping concentration and thus lowers the on-state losses without compromising the switching performance or the breakdown rating. The forward voltage drop of the proposed device reduces by 40% compared with that of a conventional FS IGBT.