A first parallel pn layer having a first n-type region and a first p-type region junctioned alternately and repeatedly is disposed in an element active portion. The first parallel pn layer has a striped planar layout. A second parallel pn layer having a second n-type region and a second p-type region junctioned alternately and repeatedly is disposed in a high voltage structure. The second parallel pn layer has a striped planar layout in a direction identical to that of the first parallel pn layer. An intermediate region having a third parallel pn layer and a fourth parallel pn layer of a lower impurity quantity than the first parallel pn layer is disposed between the first and second parallel pn layers, and formed by diffusing impurity implanting regions becoming the first and the second parallel pn layers formed separated from each other to a region in which no impurity is ion-implanted.