| 摘要 |
PURPOSE:To prevent a film from reducing and a layer resistance from varying by using as an interlayer inslating film between a polycrystalline silicon layer and upper wirins an insulating film of 3-layer structure of silicon oxidized film- silicon nitrided film-PSG film and reflowing the PSG film of low density. CONSTITUTION:A polycrystalline silicon film is selectively formed on a semiconductor substrate 1, the surface is thermally oxidized to form a silicon oxidized film 7. Then, a silicon nitrided film 8 is grown on the film 7, a phosphorus glass layer 9 is grown on the film 8, the layer 9 is softened, thereby smoothing the stepwise difference on the surface of the substrate 1. The smoothing step is at 950 deg.C or lower and of oxidizing at high pressure is oxidative atmosphere of 4-10kg/cm<2>. |
