Patent ID: 8084831

Claim:
A semiconductor device, comprising: an n-type transistor comprising a first gate electrode formed on a semiconductor substrate via a first gate insulating film, a first channel region formed in the semiconductor substrate under the first gate insulating film, and first source/drain regions formed in the semiconductor substrate on both sides of the first channel region, the first gate electrode comprising a first metal layer formed on the first gate insulating film to contact the first insulating film, and a first conductive layer on the first metal layer; and a p-type transistor comprising a second gate electrode formed on the semiconductor substrate via a second gate insulating film, a second channel region formed in the semiconductor substrate under the second gate insulating film, and second source/drain regions formed in the semiconductor substrate on both sides of the second channel region, the second gate electrode comprising a second metal layer formed on the second gate insulating film to contact the second insulating film, and a second conductive layer on the second metal layer, the second metal layer being thicker than the first metal layer and having the same constituent element as the first metal layer.