Patent ID: 7985678

Claim:
A method of manufacturing a semiconductor integrated circuit device, comprising steps of: (a) forming a first insulating film over a semiconductor substrate; (b) forming a mask material over the first insulating film; (c) forming a first opening in the mask material by using a first photo mask; (d) after the step (c), forming a second opening in the mask material by using a second photo mask different from the first photo mask; (e) after the step (d), removing the first insulating film by using the mask material as a mask, wherein, in the step (e), a first trench is formed in the first insulating film and is positioned at the area of the first insulating film exposed by the first opening, wherein, in the step (e), a second trench is formed in the first insulating film and is positioned at the area of the first insulating film exposed by the second opening.