Semiconductor device

A semiconductor device comprising:

• a single-crystal silicon carbide substrate having a 4H type crystal structure;
• a silicon carbide epitaxial layer having a 4H type crystal structure and formed on one main surface of the single-crystal silicon carbide substrate;
• a recessed portion and a protruding portion formed on a surface of the silicon carbide epitaxial layer and an inclined surface formed between the recessed portion and the protruding portion;
• a first contact area of first conductivity type formed on the inclined surface side of a bottom surface of the recessed portion;
• a second contact area of second conductivity type in contact with the first contact area at the bottom surface of the recessed portion;
• a drift area of first conductivity type formed on an upper surface of the protruding portion;
• a body area of second conductivity type formed on the inclined surface between the first contact area and the drift area;
• a gate insulating film that covers the inclined surface;
• a gate electrode formed on the gate insulating film;
• a source electrode formed on the first contact area and the second contact area;
• and
• a drain electrode formed on the other main surface of the single-crystal silicon carbide substrate,
• wherein an angle of the inclined surface with respect to the one main surface of the single-crystal silicon carbide substrate is 40° or more and 70° or less,
• wherein a boundary between the drift area and the body area is located at the inclined surface,
• wherein the boundary is vertical to the one main surface of the single-crystal silicon carbide substrate, and
• wherein an impurity concentration in the body area is 1×1017 cm−3 or more and 3×1019 cm −3 or less.