MANUFACTURE OF BIPOLAR TYPE SEMICONDUCTOR DEVICE

摘要

PURPOSE:To prevent a situation wherein a short circuit fails to be established between an external base region and activation base region by a method wherein a lamination of a non-single-crystal silicon film and metal silicide film is subjected to etching for the removal of the metal silicide film and the remaining silicon film is subjected to oxidation for the formation of a lead-out electrode. CONSTITUTION:On a P type silicon substrate 1, an N+ type buried region 2, field oxide film 4, and N+ type collector contact region 5 are formed. Then a polycrystalline silicon film 6, MoSi2 film 7 are deposited. Etching is accomplished for the formation of a lamination pattern of the films 6, 7. A process follows of the selective implantation of boron ions. An SiO2 film 8 is deposited, the films 7, 8 are subjected to etching with a resist 9 serving as a mask for the exposure of the polycrystalline silicon film 6. Thermal oxidation is accomplished for the conversion of the exposed portion of the film 6 into an oxide film 11 for an electrode 10 for leading out a base. Heat treatment follows wherein boron is diffused for the formation of a P+ type external base region 12 and boron ions are implanted through the opening for the formation of a P type activation base region 13. With the surface of an epitaxial layer 3 being not affected by etching, the regions 12, 13 are ensured to be connected by a short circuit.