| 摘要 |
PURPOSE:To obtain a high integrated system by a method wherein an element for the great electric power use and a plural number of elements for the small signal use are installed by using the conventional preparation technology on a semiconductor substrate. CONSTITUTION:An N<-> epitaxial layer on an N<3> substrate 10 is separated from a P<+> layer 1 and an N<+> embedded collector 2 of a transistor for the small signal use is installed. On this upper plane, an N<-> epitaxial layer 12 is formed and it is separated by a P<+> layer 4 and an N<+> layer 5 is connected with an N<+> embedded layer 2. Apart from these, on the N<-> layer 12 a P<+> base 13, an N<+> emitter 14 of a transistor A for the great power use are installed sequentially. Next thereto, a P<+> base 6, an N<+> emitter 7 of a transistor for the small signal use are formed within an N<-> island 12. With this constitution, a collector layer of the transistor A for the great power use can be formed in a required thickness and it is the same as that of individual transistor, as a result, a high withstand voltage element can be formed and the collector covers the whole substrate 10 and its area is wide and vast and is of a vertical type, on this account, a great current can be flowed. And further, the separate voltage is the same as an inverse withstand voltage of a transistor A, thus, being high. In this way, mass-production is feasible with the conventional technology. |
