| 摘要 |
PURPOSE:To obtain a semiconductor device characterized by a long life and high reliability by providing a silicon nitride film which is formed on a first electrode layer as an insulating layer for a capacitor and a silicon oxide film which is formed on the upper surface of the silicon nitride layer, and specifying the thickness of the silicon oxide film. CONSTITUTION:A capacitor having first and second electrode layers 18 and 22 and an insulating layer which is formed between the electrode layers 18 and 22 is provided. The insulating layers of the capacitor is formed of the following films: a lower oxide film 19 which is formed by natural oxidation of the upper surface of the first electrode layer 18 and comprises silicon; a nitride film 20 which is formed on the film 19 and comprises silicon nitride; and an upper oxide film 21 which is formed on the film 20 and comprises silicon oxide. The thickness of the upper oxide film 21 is made to be 25Angstrom or more and 35Angstrom or less. Therefore, the defect density in the silicon nitride film 20 is decreased. Even if the device is used for a long time, charge accumulation in the silicon oxide is suppressed. In this way, the semiconductor device having the capacitor characterized by a long life and high reliability can be obtained. |
