| 摘要 |
PURPOSE:To prevent the formation of an interfacial silicon oxide film and to increase the capacity of a capacitor, by making the upper part of a lower electrode out of a titanium nitride film. CONSTITUTION:A lower electrode 18 is made out of a titanium nitride film on the whole surface of a silicon substrate 1 having a field insulating film 2, word limes 4, and a silicon oxide film 5. On the whole surface of the lower electrode 18, a tantalum oxide film 17 is formed by thermal CVD using pentaethoxytantalum and oxygen. And the surface of a titanic acid nitride film constituting the lower electrode 18 being a base by existing oxygen during the CVD reaction is oxidized, and an interfacial titanium oxide film 19 is formed. After that an upper electrode 11 is made out of an N<-> type polycrystal silicon film on the whole surface of the tantalum oxide film 17, and a DIWM capacitor is completed. Consequently, it becomes possible to increase the capacitance per unit area of the capacitor and integrate DRAMs with higher density. |
