| 摘要 |
PURPOSE:To integrate a high pressure resistance circuit element and a low resistance circuit element simultaneously, by providing a high impurity concentration layer, which adjoins a dielectric film, and a medium impurity concentration semiconductor layer between the layer and an adjoining semiconductor layer. CONSTITUTION:Between a high impurity concentration layer n<+>, which adjoins a dielectric film, and a semiconductor layer nB or nC, which adjoins the layer n<+>, a semiconductor layer n, whose impurity concentration is medium between those of the two layers, is formed. In an island region 11, a wiring 20 makes ohmic contact with the layer n and wirings 17-19 do not make ohmic contact, and therefore, the layer n becomes a field alleviating layer and the layer n<+> functions as a channel stopper. In an island region 12, a wiring 23 of a collector terminal makes ohmic contact with the layer n, and current passes to the layer n<+>, the layer n and the layer nC. The layer nC is made thinner by thickness of the layer n, and specific resistance of the layer n is lower, and therefore, saturation resistance of a transistor made in the region 12 is reduced. |
