Semiconductor device, method of manufacturing semiconductor device, inverter circuit, drive device, vehicle, and elevator

A method of manufacturing a semiconductor device, comprising:

• forming a mask material having an opening on a surface of a silicon carbide layer;
• forming a trench in the silicon carbide layer by using the mask material as a mask;
• performing first ion implantation for implanting carbon (C) to form a carbon region by using the mask material as a mask, a depth of the carbon region from the surface being equal to or more than twice a depth of the trench from the surface;
• forming a sidewall material on a side surface of the trench after the performing the first ion implantation;
• performing second ion implantation for implanting aluminum (Al) to form a first impurity region by using the sidewall material as a mask, a depth of the first impurity region from the surface being equal to or more than twice the depth of the trench from the surface;
• performing third ion implantation for implanting aluminum (Al) to form a second impurity region by using the sidewall material as a mask, a depth of the second impurity region from the surface being shallower than the depth of the first impurity region from the surface;
• and
• performing a heat treatment at a temperature equal to or more than 1600° C., after the performing second ion implantation and the performing third ion implantation,
• wherein a dose amount of carbon (C) implanted by the first ion implantation is equal to or more than 10 times a dose amount of aluminum (Al) implanted by the second ion implantation,
• an aluminum (Al) concentration of the second impurity region is more than an aluminum (Al) concentration of the first impurity region,
• the aluminum (Al) concentration of the first impurity region is more than 1×1017 cm−3, and
• the aluminum (Al) concentration of the second impurity region is more than 1×1020 cm−3.