Semiconductor device and method for fabricating the same

A semiconductor device, comprising:

• a substrate including a first active region and a second active region;
• an NMIS transistor provided on the first active region;
• and
• a PMIS transistor provided on the second active region, wherein
• the NMIS transistor includes a first gate insulating film provided on the first active region and containing a high-k dielectric and a first gate electrode provided on the first gate insulating film and containing a metal material,
• the PMIS transistor includes a second gate insulating film provided on the second active region and containing a high-k dielectric and a second gate electrode provided on the second gate insulating film and containing a metal material,
• a side surface of the first gate insulating film is located at an inner side of a side surface of the first gate electrode, and
• a ratio of a length of the first gate insulating film along a gate length direction to a length of the first gate electrode along the gate length direction is lower than a ratio of a length of the second gate insulating film along the gate length direction to a length of the second gate electrode along the gate length direction.