| 摘要 |
PURPOSE:To enable a capacitor large enough in capacity to be easily formed by a method wherein a large number of mask materials which are larger than polycrystalline silicon in etching resistance are formed on the surface of a polycrystalline silicon film, a large number of irregularities are provided to the polycrystalline layer, and a dielectric layer and a second conductive layer are successively deposited. CONSTITUTION:A large number of island-shaped masking materials 9 are provided to the surface of a polycrystalline silicon film 6, where the masking material 9 is formed of material which is larger than polycrystalline silicon in etching resistance. The polycrystalline silicon film is etched until the masking materials 9 are completely removed, whereby the polycrystalline silicon film 6 where irregularities are exposed on the surface can be obtained. Phosphorus is made to diffuse into the polycrystalline silicon film 6 by the use of oxy phosphorus chloride, and a first conductive layer 6a is formed. Furthermore, a silicon nitride film 10 and a silicon oxide film 11 are successively formed on the surface of the first conductive layer 6a to constitute a dielectric layer 12, and a second polycrystalline silicon film 13 is patterned into a second conductive layer 13a. By this setup, irregularities are easily formed on the surface of a conductive layer which constitutes a capacitor. |
