| 摘要 |
PURPOSE:To increase the thickness of an insulating layer and to cover the surface of a polysilicon completely with a thermally oxidized film by laminating a non-doped polysilicon on the thermally oxidized film and selectively oxidizing the polysilicon by a nitrided film. CONSTITUTION:A P type base region 1 and an N type emitter region 2 are formed. At this time, an oxidized film 3 is formed on the surface. Then, a polysilicon 5 is laminated on the overall surface, and selectively etched to form a base and collector junction at the periphery. A nitrided film 4 is laminated on the portion except the polysilicon layer 5 at the outer periphery of the region 1, with the film as a mask of oxygen only the surface of the exposed layer 5 is oxidized to alter to the oxidized film 6. A contacting hole is opened at the film 3 to form aluminum electrodes 7. |
