| 摘要 |
PURPOSE:To prevent a short-circuit between each of layers, while to hold capacitance between the layers at a prescribed constant value by a method wherein the two polycrystalline silicon layers provided on a semiconductor substrate are made to have overlapping structure mutually interposing a dielectric containing a silicon nitride film between them. CONSTITUTION:The dielectric containing the silicon nitride film 17 is provided between the polycrystalline silicon layer 15 and the polycrystalline silicon layer 19 extending over the whole region of the overlapping part. An insulating film to cover the part other than the connecting part of the polycrystalline silicon layer 19 to an outside wiring is constituted of a silicon oxide film 20 and phosphorus glass 18. Outside wirings 21-23 are provided respectively at the opening parts of the lower electrode wiring 15, the upper electrode wiring 19 and an N<+> type layer 12. Moreover the silicon nitride film 17 is provided directly under the connecting part of the outside wiring 22 to the upper electrode wiring 19. Because the silicon nitride film is not corroded by a corrosive liquid, hydrogen fluoride corrosive liquid, for example, to form an opening in the second insulating film consisting of the silicon oxide film 20 and phosphorus glass 18, insulation between the lower electrode wiring and the upper electrode wiring can be maintained. |
