Patent ID: 7737491

Claim:
A semiconductor device of IGBT comprising: an emitter electrode; a top region of a second conductivity type connected to the emitter electrode; a deep region of the second conductivity type; an intermediate region of a first conductivity type isolating the top region and the deep region; a collector region of the first conductivity type connected to the deep region, the collector region being isolated from the intermediate region by the deep region; a collector electrode connected to the collector region; a gate electrode facing a portion of the intermediate region via an insulating layer, the portion of the intermediate region isolating the top region and the deep region; and a barrier region comprising a semiconductor region of the second conductivity type formed within the intermediate region, wherein the intermediate region comprises a dense portion directly connected to the emitter electrode, and a main portion connected to the emitter electrode via the dense portion, wherein the barrier region is in contact with the dense portion, and is separated from the deep region by the main portion.