| 摘要 |
PURPOSE:To enable a high quality oxide insulating film to be formed by a method wherein a gaseous oxide in the ratio exceeding specific range to an inert gas is used for the sputtering process to form the title oxide insulating film. CONSTITUTION:A tantalum oxide film is formed on a silicon semiconductor and then an electrode is formed on the tantalum oxide film by electron beam evaporation process while the results of detected electrical characteristics are as shown in the figures. Within the figures, the slip from the ideal value of the flat band voltage in the less volume of Ar gas than oxidative gas i.e., not exceeding 25 minal % is reduced. A lower side electrode 2 is formed on a substrate 1 by sputtering process of Ar only in an island shape and then an insulating film 8 of tantalum oxide is formed on the electrode 2 next Al as an upper side electrode 4 is formed by Al evaporation process to complete a capacitor. In said procedures, since the breakdown strength is increased when the oxygen number during the film formation process is rapidly decreased at the voluminal % of Ar exceeding 25%, Ar is to be added at the voluminal % during the film formation process not exceeding 25% generally to oxygen of 100%, while in the ratio of specific dielectric constant to oxygen, the oxygen % is the, higher the better. |
