Patent ID: 7361932

Claim:
A semiconductor device of a dual-gate structure comprising: a P-channel type field-effect transistor formed at a first region of a substrate and an N-channel type field-effect transistor formed at a second region of the substrate, said device comprising: a gate electrode including a polycrystalline silicon film continuously formed on the substrate to cover the first and second regions and a metal silicide film formed on the polycrystalline silicon film, wherein the polycrystalline silicon film has a P-type part located on the first region and an N-type part coming into contact with the P-type part and located on the second region, the P-type part is thicker than the N-type part, an end part of the P-type part located above the N-type part and at the interface between the P-type part and the N-type part of the polycrystalline silicon film is normally tapered, and a taper angle of the normally tapered end part is 40 through 60 degrees both inclusive.