| 摘要 |
PURPOSE:To enable a Schottky barrier diode used for a bipolar integrated circuit adapted for high speed operation and high integration by a method wherein a P-type diffusion layer is formed in a substrate through a thermal treatment using a polysilicon film formed in an opening as a diffusion source, and a metal electrode containing a metal silicide layer is formed on the opening. CONSTITUTION:A silicon oxide film 2, a BSG film 3, and a silicon nitride film 4 are formed on the surface of a silicon substrate 1. Then, an opening is formed, a polysilicon film is formed, and boron is made to diffuse into all the polysilicon film on the side wall of the opening through a thermal treatment to form a P-type polysilicon film 5a and a non-doped polysilicon film 5b in which no boron is diffused. In succession, the non-doped silicon film 5b is selectively etched, which is then thermally treated in an atmosphere of nitrogen to form a P-type diffusion layer 6 which serves as a guard ring, a platinum silicide layer 7 is formed, and a Ti-W film 8 and an aluminum electrode 9 are formed. |
