Patent ID: 7579264

Claim:
A method for manufacturing a semiconductor device, comprising the steps of: (a) forming a first region and a channel stopper in an upper region of a semiconductor substrate by: (1) selectively forming a first impurity implantation region with a first impurity concentration in the upper region of the semiconductor substrate by selectively implanting ions in the upper region of the semiconductor substrate; (2) selectively forming a second impurity implantation region with a second impurity concentration which is greater than the first impurity concentration in the upper region of the semiconductor substrate by selectively implanting ions in the upper region of the semiconductor substrate; and (3) simultaneously forming by thermal diffusion treatment a first impurity diffusion region with a third impurity concentration and a second impurity diffusion region with a fourth impurity concentration which is greater than the third impurity concentration in the first region, and a third impurity diffusion region with fifth impurity concentration which is greater than the third impurity concentration in the channel stopper; (b) forming a first insulating film over the semiconductor substrate; (c) forming a laminated body on the first insulating film by (1) forming a polysilicon film on the first insulating film; (2) forming a contact hole that is in contact with the first region on the semiconductor substrate through the first insulating film and the polysilicon film; and (3) forming a metal film on the polysilicon film and in the contact hole so that the metal film is separated from the first insulating film by means of the polysilicon film; and (d) forming a first wiring layer and a first electrode simultaneously by patterning the laminated body.