A semiconductor device with enhanced semiconductor characteristics that is useful for power devices. A semiconductor device, including: an n-type semiconductor layer; an electrode; two or more p-type semiconductors provided between the n-type semiconductor layer and the electrode, the n-type semiconductor layer containing a corundum-structured crystallin oxide semiconductor as a major component, a number of the two or more p-type semiconductor that is equal to or more than three, and the two or more p-type semiconductors that are embedded in the n-type semiconductor layer.