Abstract: A reverse blocking semiconductor device includes a base region of a first conductivity type and a body region of a second, complementary conductivity type, wherein the base and body regions form a pn junction. Between the base region and a collector electrode an emitter layer is arranged that includes emitter zones of the second conductivity type and at least one channel of the first conductivity type. The channels extend through the emitter layer between the base region and the collector electrode and reduce the leakage current in a forward blocking state.

Abstract: A semiconductor device includes an IGBT cell including a second-type doped drift zone, and a desaturation semiconductor structure for desaturating a charge carrier concentration in the IGBT cell. The desaturation structure includes a first-type doped region forming a pn-junction with the drift zone, and two portions of a trench or two trenches arranged in the first-type doped region and beside the IGBT cell in a lateral direction. Each of the two trench portions or each of the two trenches has a wide part below a narrow part. The wide parts confine a first-type doped desaturation channel region of the first-type doped region at least in the lateral direction. The narrow parts confine a first-type doped mesa region of the first-type doped region at least in the lateral direction. The desaturation channel region has a width smaller than the mesa region in the lateral direction, and adjoins the mesa region.