A first layer constituting a first surface of a silicon carbide layer and of a first conductivity type is prepared. An internal trench is formed at a face opposite to the first surface of the first layer. Impurities are implanted such that the conductivity type of the first layer is inverted on the sidewall of the internal trench. By the implantation of impurities, there are formed from the first layer an implantation region located on the sidewall of the internal trench and of a second conductivity type, and a non-implantation region of the first conductivity type. A second layer of the first conductivity type is formed, filling the internal trench, and constituting the first region together with the non-implantation region.