A method of manufacturing a semiconductor device comprises steps of: forming a semiconductor stack by growing an AlGaN layer or an InAlN layer, an AlN layer, and a GaN layer on a substrate in this order; forming a recess in the semiconductor stack by a dry etching from a surface of the semiconductor stack, the surface being opposite to the substrate; growing a GaN region in the recess; and forming an ohmic electrode on the GaN region; wherein in the forming of the recess, the dry etching is stopped in response to the recess reaching the AlN layer.