Patent ID: 8592893
Filing Date: 2013-11-26
Classification: H01L

Abstract:
1. A power semiconductor device comprising: a first semiconductor layer of a first conductivity type; a second semiconductor layer of the first conductivity type and a third semiconductor layer of a second conductivity type that are provided periodically in a horizontal direction on the first semiconductor layer; a fourth semiconductor layer of the second conductivity type provided on the third semiconductor layer; a fifth semiconductor layer of the first conductivity type selectively provided on a surface of the fourth semiconductor layer; a first main electrode connected to the first semiconductor layer; a second main electrode connected to the fourth semiconductor layer and the fifth semiconductor layer; a first insulating film provided on sidewalls of a trench that reaches from a surface of the fifth semiconductor layer to the second semiconductor layer; a second insulating film provided closer to a bottom side of the trench than the first insulating film and having a higher permittivity than the first insulating film; and a control electrode embedded in the trench via the first insulating film and the second insulating film.