Patent ID: 8729600

Claim:
A semiconductor device comprising: a first conductivity-type semiconductor substrate having a substrate surface; a plurality of second conductivity-type channel regions disposed adjacent to the substrate surface; a plurality of second conductivity-type thinning-out regions disposed adjacent to the substrate surface, the thinning-out regions and the channel regions being arranged in a direction parallel to the substrate surface in such a manner that at least one thinning-out region is disposed between the adjacent channel regions; a first conductivity-type emitter region disposed at a surface layer portion of each of the channel regions; a first conductivity-type hole stopper layer disposed in each of the thinning-out regions to divide the thinning-out region into a first part adjacent to the substrate surface and a second part adjacent to a bottom of the thinning-out region; an emitter electrode connected to the emitter region and the first part; a collector layer disposed in the semiconductor substrate at a position separated from the channel regions and the thinning-out regions; and a collector electrode electrically connected to the collector layer, wherein the hole stopper layer has an area density of equal to or less than 4.0×10 12 cm −2 .