Patent ID: 8129792

Claim:
A semiconductor device comprising: a semiconductor substrate; an n-type semiconductor region and a p-type semiconductor region formed to be separated from each other on the semiconductor substrate; an interlayer insulating film formed on the semiconductor substrate and having a first trench and a second trench formed to reach the n-type semiconductor region and the p-type semiconductor region, respectively; a first gate insulating film formed along first side walls and a first bottom of the first trench; a second gate insulating film formed along second side walls and a second bottom of the second trench; a first metal layer formed along the first side walls and the first bottom of the first trench via the first gate insulating film; a second metal layer formed along the second side walls and the second bottom of the second trench via the second gate insulating film; a third metal layer formed on the second metal layer and containing at least one selected from the group consisting of a simple substance of a member, a nitride of the member, a carbide of the member and an oxide of the member, the member being at least one metal element selected from the group consisting of alkaline earth metal elements, Sc, Y, lanthanoids, and actinoids; first source/drain regions formed on the n-type semiconductor region to be opposed to each other with a portion of the first gate insulating film formed on the first bottom interposed therebetween; and second source/drain regions formed on the p-type semiconductor region to be opposed to each other with a portion of the second gate insulating film formed on the second bottom interposed therebetween.