A semiconductor device includes a substrate including a first region and a second region, a first silicon-germanium film which is conformally formed inside a surface of the substrate of the first region and defines a first gate trench, a first gate insulating film which extends on the first silicon-germanium film along a profile of the first gate trench and is in physical contact with the first silicon-germanium film, a first metallic gate electrode on the first gate insulating film, a source/drain region formed inside the substrate on both sides of the first metallic gate electrode, a second gate insulating film in the second region and a second metallic gate electrode on the second gate insulating film.