| 摘要 |
PURPOSE:To restrain an interface between a lower polycrystalline silicon and an upper metal silicide from decreasing in boron concentration by a method wherein the upside and side face of an electrode wiring are covered with a nitride film. CONSTITUTION:A base lead-out electrode composed of a P<+>-type polycrystalline silicon layer 6 and a tungsten silicide layer 13 and connected to a base diffusion layer 8 is formed above an outer base diffusion layer 7. Furthermore, a nitride film 9 and a side wall 9A of nitride are formed to serve as an interlayer insulating film covering the lead-out electrode composed of the layers 6 and 13, and an emitter electrode of an N<+>-type polycrystalline silicon layer 11 connected to an emitter diffusion layer 12 is formed thereon. By this setup, an interface of the lower polycrystalline silicon layer 11 with the upper metal silicide 13 is restrained from decreasing in boron concentration, so that a bipolar transistor which is restrained from increasing in base resistance and capable of executing a high speed switching operation can be realized. |
