Patent ID: 7468540

Claim:
A semiconductor device, comprising: a first MIS transistor which is driven at a relatively low source voltage; and a second MIS transistor which is driven at a relatively high source voltage, the first MIS transistor and the second MIS transistor being formed on the same semiconductor substrate, wherein the first MIS transistor includes: a first gate insulating film formed on the semiconductor substrate; a first gate electrode formed on the first gate insulating film; a first sidewall insulating film formed at each side face of the first gate electrode; and a first impurity diffusion region formed in a region of the semiconductor substrate which is located on each side of the first gate electrode, the second MIS transistor includes: a second gate insulating film formed on the semiconductor substrate; a second gate electrode formed on the second gate insulating film; a second sidewall insulating film formed at each side face of the second gate electrode; and a second impurity diffusion region formed in a region of the semiconductor substrate which is located on each side of the second gate electrode, and a first channel region is formed beneath the first gate insulting film so as not to be offset relative to the first impurity diffusion region while a second channel region is formed beneath the second gate insulating film so as to be offset relative to the second impurity diffusion region.