A semiconductor device may include: an n type of layer disposed on a first surface of a substrate; a p+ type of region disposed on the first surface of the substrate; a p− type of region disposed at a top portion of the n type of layer; a first electrode disposed on the p+ type of region and the p− type of region; and a second electrode disposed on a second surface of the substrate, wherein the side surface of the p+ type of region and the side surface of the n type of layer are in contact, and the thickness of the p+ type of region is the same as the thickness of the n type of layer and the thickness of the p− type of region.