| 摘要 |
PURPOSE:To prevent a parasitic element, and to eliminate the need for tub bonding by forming a P<+> type layer having high concentration onto the opposite main surface of a P<-> type semiconductor substrate and making contact with a metallic surface as a supporter ohmic. CONSTITUTION:An N<-> type Si layer 2 is formed to the main surface of the P<-> type Si substrate 1 having high resistance. A P type isolation layer 3 is formed selectively to the layer 2. The P<+> type diffusion layer 10 having high concentration is formed to the main surface at the reverse side of the substrate 1. A P<+> type base region 4 is shaped to the surface of an N<-> type island region 2 isolated by the P<+> isolation layer 3. An N inversion layer between a metallic film 6 as a mounting section to a supporting metallic plate 5 and the substrate 1 is not formed by the layer 10 of the back of the substrate 1. |
