Power semiconductor device having semiconductor-layer-forming position controlled by ion implantation without using photoresist pattern, and method of manufacturing such power semiconductor device

摘要

A first insulator (710) having an opening within a central region (551) is formed on a main surface (61S) of an epitaxial layer (610). Then, p-type impurities are ion implanted through the opening of the first insulator (710) and then heat treatment is carried out, thereby to form a p base layer (621) in the main surface (61S). An insulating film is formed to fill in the opening and then etched back, thereby to form a second insulator (720) on a side surface (71W) of the first insulator (710). Under conditions where the second insulator (720) is present, n-type impurities are ion implanted through the opening and then heat treatment is carried out, thereby to form an n<+> source layer (630) in the main surface (61S) of the p base layer (621).