摘要 |
A semiconductor device includes a semiconductor substrate of a first conductivity type and a semiconductor layer of a second conductivity type opposite to the first conductivity type formed on the substrate. In the layer are formed a first semiconductor region of the first conductivity type, having a low impurity concentration and formed deep; and a second semiconductor region in a surface area of the layer including the surface of the first semiconductor region. The second region has an impurity concentration higher than that of the first region and formed shallower than it. A power source voltage terminal is connected to the substrate and supplies a voltage applied thereto to the second region through the substrate and the layer. |