| 摘要 |
PURPOSE:To contrive the realization of the self-alignment between a base, an emitter and a collector, form element dimensions more finely, and thus enable to improve the frequency characteristic, by forming semiconductor polycrystalline layers respectively on the surface of the high density base region and the emitter region. CONSTITUTION:An N<+> burried layer 2 by partial diffusion of Sn (antimony) is formed on the surface of a P<-> type Si substrate 1, and isolation oxide films 5 which surround the base and the collector by isolating them each other on the surface are formed. An Si3N4 film 7 is deposited over the entire surface, and then B implantation is performed into the ring formed part. A P<+> base contact part 11 is formed deeper than a P layer 9 by high density B ion implantation and diffusion through the poly Si layers 6. A contact photoetching is performed, and an emitter Al electrode 15 is formed to the emitter via a poly Si layer 6 by wiring pattern etching, while a collector Al electrode 16 which directly connect the N<+> contact layer is formed to the collector. |
