Semi-superjunction IGBT with floating p-pillar and p-ring for low losses and high breakdown voltage

The semi-SJ IGBTs with floating p-pillar and p-ring are proposed and studied. The floating p-pillar separated from the p-base region by a trench emitter is able to enhance the carrier storage effect so as to reduce the on-state voltage drop (V CE(sat) ). In addition, the p-ring shields high electric field at the bottom of the trench emitter, which helps to reduce the integral of hole impact ionization so as to prevent pre-breakdown. Compared to the conventional semi-SJ IGBT, the proposed semi-SJ IGBTs is able to obtain the same breakdown voltage (V B ) and a 38% lower V CE(sat) under turn-off loss E off = 5 mJ/cm ² .