Patent ID: 8796694

Claim:
A semiconductor device comprising: a semiconductor substrate made of silicon carbide and having a surface, a normal vector for the surface having an off angle with respect to a <0001>direction or a <000-1>direction; a semiconductor layer of a first conductivity type formed on the semiconductor substrate, a first semiconductor region of a second conductivity type formed in a surface region of the semiconductor layer; a source region of a first conductivity type formed in a surface region of the first semiconductor region; a second semiconductor region of a second conductivity type formed in the surface region of the semiconductor layer, the second semiconductor region having a lower part and an upper part; a gate insulation film formed on the semiconductor layer, the first semiconductor region, and the source region; a gate electrode formed on the gate insulation film; a source electrode formed on the source region and the second semiconductor region; and a drain electrode formed on a back surface of the semiconductor substrate, wherein at least one end of the bottom surface of the second semiconductor region is perpendicular to an off angle direction of the normal vector with respect to the <0001>direction or the <000-1>direction, the lower part of the second semiconductor region contacts a side surface of the source region and a side surface of the first semiconductor region, and has a bottom surface located in a lower position relative to a bottom surface of the first semiconductor region, and the upper part of the second semiconductor region contacts a side surface of the source region, and has a bottom surface located in a higher position relative to a bottom surface of the source region.