Patent ID: 7189637

Claim:
A method of manufacturing a semiconductor device comprising the steps of: (a) forming a first wiring and a second wiring over a semiconductor substrate; (b) after said step (a), forming a first insulating film in contact with said first and second wirings; (c) after said step (b), forming a second insulating film over said first insulating film; (d) after said step (c), cleaning a surface of said second insulating film; (e) after said step (d), forming a plurality of holes in said first and second insulating films; and (f) after said step (e), forming a third wiring over said second insulating film, said third wiring being connected to said first and second wirings via said holes, wherein, in between said step (a) and said step (e), said first wiring is in a floating state and said second wiring is connected to said semiconductor substrate, and wherein said first insulating film is formed so as to have an electric conductivity higher than said second insulating film, so that an electric charge accumulated in said step (d) is escaped through said first insulating film.