SEMICONDUCTOR DEVICE AND METHOD FOR PRODUCING SEMICONDUCTOR DEVICE
A light emitting device of the present invention includes a substrate, a semiconductor element, a first external electrode, and a second external electrode. The substrate has a first conductivity type and contains a single-crystal silicon. The substrate has an upper surface and a lower surface on which thermally-oxidized films are formed. A first opening portion and a second opening portion are formed to be mutually spaced in the thermally-oxidized film formed on the lower surface. The substrate includes a diode structure unit that includes a first well region and a second well region. The first well region is formed in a first region along the lower surface, is exposed at the first opening portion, and has a second conductivity type different from the first conductivity type. The second well region is formed in a second region along the lower surface in the first region, is exposed at the second opening portion, and has the first conductivity type. The semiconductor element is disposed on the substrate and includes a semiconductor layer. The first external electrode is formed on a lower surface of the thermally-oxidized film and in contact with the first well region at the first opening portion. The second external electrode is formed on the lower surface of the thermally-oxidized film, spaced from the first external electrode, and in contact with the second well region at the second opening portion. The second well region extends to the first opening portion side exceeding a middle line between the first opening portion and the second opening portion along the lower surface of the substrate.