A vertical semiconductor apparatus includes: a gallium nitride substrate; a gallium nitride semiconductor layer on the gallium nitride substrate; a p-type impurity region in the gallium nitride semiconductor layer and having an element to function as an acceptor for gallium nitride; an n-type impurity region in the p-type impurity region and having an element to function as a donor for gallium nitride; and an electrode provided contacting a rear surface of the gallium nitride substrate. The element to function as the donor in the n-type impurity region includes: a first impurity element to enter sites of gallium atoms in the gallium nitride semiconductor layer; and a second impurity element different from the first impurity element and to enter sites of nitrogen atoms in the gallium nitride semiconductor layer. In the n-type impurity region, a concentration of the first impurity element is higher than that of the second impurity element.