Semiconductor device and manufacturing method thereof

A semiconductor device, comprising:

• a silicon substrate;
• a P-channel field effect transistor comprising a first gate insulating film over said silicon substrate, a first gate electrode on the first gate insulating film, and first source and drain regions;
• and
• an N-channel field effect transistor comprising a second gate insulating film over said silicon substrate, a second gate electrode on the second gate insulating film, and second source and drain regions,
• wherein the first gate electrode comprises, at least in part in contact with the first gate insulating film, a crystallized Ni silicide region containing p-type impurities;
• the second gate electrode comprises, at least in part in contact with the second gate insulating film, a crystallized Ni silicide region containing n-type impurities;
• at least one of the crystallized Ni silicide regions of the first and second gate electrodes includes a first silicide region having an NiSi2 phase and a second silicide region having an NiSi phase disposed above the first silicide region;
• the silicides making up the crystallized Ni silicide regions of the first and second gate electrodes are of a composition represented by NixSi1-x(0.2≦x<0.4);
• the first gate insulating film comprises a silicon oxide film, a silicon oxynitride film or a silicon nitride film, the silicon oxide film, the silicon oxynitride film or the silicon nitride film being in contact with the crystallized Ni silicide region of the first gate electrode;
• and
• the second gate insulating film comprises a silicon oxide film, a silicon oxynitride film or a silicon nitride film, the silicon oxide film, the silicon oxynitride film or the silicon nitride film being in contact with the crystallized Ni silicide region of the second gate electrode.

A semiconductor device, comprising:

• a silicon substrate;
• and
• a field effect transistor comprising a gate insulating film over the silicon substrate, a gate electrode on the gate insulating film, and source and drain regions,
• wherein said gate electrode comprises, at least in part in contact with said gate insulating film, a crystallized Ni silicide region containing an impurity element of a conductivity type opposite to a conductivity type of a channel region in the field effect transistor,
• the silicide making up said crystallized Ni silicide region is of a composition represented by NixSi1-x(0.2≦x<0.4),
• said gate insulating film comprises a silicon oxide film, a silicon oxynitride film or a silicon nitride film, the silicon oxide film, the silicon oxynitride film or the silicon nitride film being in contact with said crystallized Ni silicide region of the gate electrode, and
• the gate electrode comprises a first silicide region comprising an NiSi2 phase, the first silicide region being in contact with the gate insulating film, and a second silicide region comprising an NiSi phase, the second silicide region being above the first silicide region.

A semiconductor device, comprising:

• a silicon substrate;
• a P-channel field effect transistor comprising a first gate insulating film over said silicon substrate, a first gate electrode on the first gate insulating film, and first source and drain regions;
• and
• an N-channel field effect transistor comprising a second gate insulating film over said silicon substrate, a second gate electrode on the second gate insulating film, and second source and drain regions,
• wherein the first gate electrode comprises, at least in part in contact with the first gate insulating film, a crystallized Ni silicide region containing p-type impurities,
• the second gate electrode comprises, at least in part in contact with the second gate insulating film, a crystallized Ni silicide region containing n-type impurities,
• the silicides making up the crystallized Ni silicide regions of the first and second gate electrodes are of a composition represented by NixSi1-x(0.2≦x<0.4),
• the first gate insulating film comprises a silicon oxide film, a silicon oxynitride film or a silicon nitride film, the silicon oxide film, the silicon oxynitride film or the silicon nitride film being in contact with the crystallized Ni silicide region of the first gate electrode,
• the second gate insulating film comprises a silicon oxide film, a silicon oxynitride film or a silicon nitride film, the silicon oxide film, the silicon oxynitride film or the silicon nitride film being in contact with the crystallized Ni silicide region of the second gate electrode, and
• the first and second gate electrodes each comprise a first silicide region comprising an NiSi2 phase, the first silicide region being in contact with the first or second gate insulating film, and a second silicide region comprising an NiSi phase, the second silicide region being above the first silicide region.