Patent ID: 8242572
Filing Date: 2012-08-14
Classification: H01L

Abstract:
1. A semiconductor apparatus comprising: a supporting base; a first insulator film on the supporting base; a semiconductor layer of a first conductivity type on the first insulator film; a trench extended from a surface of the semiconductor layer to the first insulator film, the trench comprising a second insulator film buried therein; a first semiconductor layer of the first conductivity type surrounded by the trenches; a second semiconductor layer of the first conductivity type in a surface portion of one of the first semiconductor layers, the second semiconductor layer being doped more heavily than the first semiconductor layer; a third semiconductor layer of a second conductivity type in the surface portion of the one of the first semiconductor layers, the third semiconductor layer being formed selectively around the second semiconductor layer with a spacing left between the third semiconductor layer and the second semiconductor layer; a fourth semiconductor layer of the first conductivity type in a surface portion of the third semiconductor layer, the fourth semiconductor layer being doped more heavily than the third semiconductor layer; a fifth semiconductor layer of the second conductivity type in the surface portion of the third semiconductor layer, the fifth semiconductor layer being doped more heavily than the third semiconductor layer; a first main electrode in contact with the second semiconductor layer; a second main electrode in contact with the fourth and fifth semiconductor layers; a gate electrode above an extended portion of the third semiconductor layer extended between the fourth semiconductor layer and the one of the first semiconductor layers with a gate insulator film interposed between the gate electrode and the extended portion; a sixth semiconductor layer of the second conductivity type in the surface portion of the one of first semiconductor layers, the sixth semiconductor layer being in contact with the second semiconductor layer, the sixth semiconductor layer being extended toward the trench; a seventh semiconductor layer of the second conductivity type in the surface portion of the one of the first semiconductor layers, the seventh semiconductor layer being in contact with the sixth semiconductor layer, the seventh semiconductor layer being extended toward the trench, the seventh semiconductor layer being doped more heavily than the sixth semiconductor layer; a high-potential wiring above the sixth and seventh semiconductor layers with a third insulator film interposed between the high-potential wiring and the sixth and seventh semiconductor layers, the high-potential wiring connecting the first main electrode and another one of the first semiconductor layers in adjacent to the one of the first semiconductor layers crossing over the trench; and the third semiconductor layer being spaced apart from the seventh semiconductor layer, so that the third semiconductor layer does not cross the seventh semiconductor layer.