To provide a semiconductor element having Schottky junction structure superior in backward direction characteristic, without sacrificing the forward direction characteristic, a Schottky barrier diode, and a semiconductor substrate for forming a Schottky junction for forming the diode.

In a Schottky barrier diode, in which a metal layer is formed on an epitaxial layer surface of a semiconductor substrate for forming a Schottky junction in which an epitaxial layer containing impurities, is formed on a silicon substrate, the concentration of an impurity in the epitaxial layer is constant from the surface to a prescribed depth, gradually increasing from the prescribed depth toward the silicon substrate, and sharply increasing toward the substrate in the vicinity of the silicon substrate.