| 摘要 |
PURPOSE:To obtain a fine connection with a high accuracy easily by connecting an Al wiring and a semiconductor substrate through a poly Si left at the connection following the total conversion thereof of into SiO2. CONSTITUTION:An opening is etched through an SiO2 film 2 on an Si substrate 1 and a poly Si wiring 3 is provided thereon. P-doped poly Si 7 is laminated by a decompression CVD method and a mask of Si3N4 8 is applied thereon. The poly Si 7 is converted into PSG 9 by a high pressure oxidation. After Si3N4 8 is etched by a solution of phosphoric acid, PSG 9 is smoothed by treatment at about 1,000 deg.C while a P-diffusion layer is formed in the substrate 1. When an Al wiring 6 is laminated thereon, the PSG layer is electrically connected to the substrate through the poly Si 7. Accordingly, the smooth step allows P to be diffused through the substrate from the PSG eliminating disconnection. There is no penetrating of Al thereby improving the reliability. |
