In order to improve characteristics of an IGBT, particularly, to reduce steady loss, turn-off time and turn-off loss, a thickness of a surface semiconductor layer is set to about 20 nm to 100 nm in an IGBT including: a base layer; a buried insulating film provided with an opening part; the surface semiconductor layer connected to the base layer below the opening part; a p type channel forming layer formed in the surface semiconductor layer; an n+ type source layer; a p+ type emitter layer; a gate electrode formed over the surface semiconductor layer via a gate insulating film; an n+ type buffer layer; and a p type collector layer.