Patent ID: 8198155

Claim:
A method of manufacturing a semiconductor device, for forming an N-type transistor in a first region on a substrate, and forming a P-type transistor in a second region on the substrate, the method comprising: forming a first gate insulation film containing silicon, on the substrate in the first and second regions; forming a second gate insulation film containing first metal and oxygen, on the first gate insulation film in the first region; forming a third gate insulation film containing second metal different from the first metal and oxygen, on the first gate insulation film in the second region; forming a fourth gate insulation film containing hafnium, on the second and third gate insulation films in the first and second regions; depositing a first conductive film containing metal and nitrogen, on the fourth gate insulation film in the first and second regions; removing the first conductive film on the fourth gate insulation film in the first region; depositing a second conductive film containing metal and nitrogen, on the fourth gate insulation film and the first conductive film in the first and second regions; introducing excess nitrogen from the first and second conductive films into the fourth gate insulation film; and etching the first and second conductive films in the first and second regions to form a gate electrode for the N-type transistor including the second conductive film, and a gate electrode for the P-type transistor including the first and second conductive films.