Patent ID: 9231081
Filing Date: 2016-01-05
CPC Classification: H01L

Claim Text:
1. A method of manufacturing a semiconductor device, comprising: forming, on a semiconductor substrate of a first conductivity type, a buried layer of a second conductivity type; forming an epitaxial layer of the second conductivity type on the buried layer; forming a body region of the first conductivity type at a certain depth from a surface of the epitaxial layer of the second conductivity type; selectively lowering a surface of the body region to form a convex-type contact region which protrudes from the lowered surface of the body region and form a shallow trench around the convex-type contact region; forming a deep trench region in the shallow trench so as to extend from a part of the lowered surface of the body region to inside of the epitaxial layer of the second conductivity type; forming a gate insulating film on an inner wall of the deep trench region; filling the deep trench region with polycrystalline silicon so that the polycrystalline silicon is held in contact with the gate insulating film; forming a source region of the second conductivity type in the shallow trench in the surface of the body region; forming a body contact region of the first conductivity type in the convex-type contact region on the surface of the body region; and forming a silicide layer for connecting the source region and the body contact region to each other, wherein the body contact region comprises an entire surface of the convex-type contact region, and the entire surface and a surface of the source region are covered with the silicide layer.