Patent ID: 8772111
Filing Date: 2014-07-08
Classification: H01L

Abstract:
1. A method of manufacturing a trench gate semiconductor device, the method comprising the steps of: (a) forming a first trench from a surface of a semiconductor substrate using an insulator film for a mask; (b) forming a polysilicon gate electrode in a lower portion of the first trench with a gate insulator film interposed between an inner wall of the first trench and the polysilicon gate electrode; (c) forming a source region in an upper side wall of the first trench using the insulator film and the polysilicon gate electrode as masks, wherein the source region is formed by oblique ion implantation into the upper sidewall of the first trench; (d) loading an insulator in an upper portion of the first trench such that an upper surface of the insulator is at a same level with the surface of the semiconductor substrate; (e) forming a second trench in a surface portion of the semiconductor substrate between the first trenches, the second trench comprising a slanted inner surface extending from a side wall of the first trench to a bottom plane of the second trench positioned lower than a lower end surface of the source region such that the source region is exposed to the slanted inner surface of the second trench; and (f) forming a body-contact region of a first conductivity type along the slanted inner surface of the second trench, wherein the body contact region is thinner than the source region.