A semiconductor device includes a first semiconductor region of a first conductivity type and formed of a material having a band gap wider than that of silicon; a first layer selectively disposed on a surface of and forming a first junction with the first semiconductor region; a second layer selectively disposed on the first semiconductor region and forming a second junction with the first semiconductor region; a first diode formed by a region including the first junction; a second diode formed by a region including the second junction; and a fourth semiconductor region of a second conductivity type and disposed in the first semiconductor region, between and contacting the first and second junctions. A recess and elevated portion are disposed on the first semiconductor region. The first and the second junctions are formed at different depths. The second diode has a lower built-in potential than the first diode.