A first layer has n type conductivity. A second layer is epitaxially formed on the first layer and having p type conductivity. A third layer is on the second layer and having n type conductivity. ND is defined to represent a concentration of a donor type impurity. NA is defined to represent a concentration of an acceptor type impurity. D1 is defined to represent a location in the first layer away from an interface between the first layer and the second layer in a depth direction. D1 in which 1≦ND/NA≦50 is satisfied is within 1 μm therefrom. A gate trench is provided to extend through the third layer and the second layer to reach the first layer. A gate insulating film covers a side wall of the gate trench. A gate electrode is embedded in the gate trench with the gate insulating film interposed therebetween.