1700V reverse-blocking IGBTs with V-groove isolation layer for multi-level power converters

1700V reverse-blocking IGBTs(RB-IGBTs) are developed for the first time as bidirectional switches in multilevel converter applications. In this work, our hybrid isolation process by combining thermal diffusion and V-Groove etching for 1200V RB-IGBTs is further developed to form 1700V devices. Sufficient blocking capability and switching robustness have been successfully demonstrated. At the same switching loss level, on-state voltage drop of 50A- rated planar gate RB-IGBT is reduced approximately 2.0V compared with that of serially connected trench-gate field-stop IGBT and FWD. Experimental benchmarking on 1200A module demonstrated that the energy loss in three-level inverter was reduced 18% by using RB-IGBTs instead of IGBT and FWD pairs at typical switching frequency for high-power, medium voltage applications.