| 主权项 |
1. A silicon carbide semiconductor device comprising:
a silicon carbide substrate including a first layer having first conductivity type, a second layer provided on said first layer and having second conductivity type, and a third layer provided on said second layer, separated from said first layer by said second layer, and having said first conductivity type, said silicon carbide substrate being provided with a trench having a side wall and a bottom portion, said side wall extending through said third layer and said second layer and reaching said first layer, said bottom portion being formed of said first layer; a gate insulating film provided on said trench, said gate insulating film including a trench insulating film and a bottom insulating film, said trench insulating film covering each of said side wall and said bottom portion, said bottom insulating film being provided on said bottom portion with said trench insulating film being interposed therebetween, said bottom insulating film having a carbon atom concentration lower than that of said trench insulating film; and a gate electrode provided in said trench, said gate electrode being in contact with a portion of said trench insulating film on said side wall. |
