| 主权项 |
1. A semiconductor device comprising:
a semiconductor substrate which comprises:
a first conductivity type drift layer;a second conductivity type body layer provided on a front surface side of the drift layer; anda first conductivity type first semiconductor layer provided on a part of a front surface of the body layer; and a trench gate extending from a front surface of the semiconductor substrate through the body layer and the first semiconductor layer to reach the drift layer, wherein the trench gate comprises a gate insulating film formed on an inner wall of a trench, and a gate electrode disposed inside of the gate insulating film, the inner wall of the trench, which is located at a depth where the inner wall makes contact with the body layer of the semiconductor substrate, is a crystal plane of the semiconductor substrate, the crystal plane is a plane perpendicular to the front surface of the semiconductor substrate, the trench comprises a first width and a second width in a transverse direction which is perpendicular to a longitudinal direction of the trench in a plan view, the first width is a width located at the front surface of the semiconductor substrate, the second width is a width located at a depth from a lower end of the first semiconductor layer to a lower end of the body layer of the semiconductor substrate, and the first width is narrower than the second width. |
