| 摘要 |
PROBLEM TO BE SOLVED: To prevent a capacitor insulating film from deteriorating in quality by a method wherein a semiconductor substrate is irradiated with ultraviolet rays in an atmosphere of chloride so as to remove a natural oxide film formed on a polycrystalline silicon film, and then a silicon nitride film is formed. SOLUTION: An element isolating region 2, a word line 3, and a CVD silicon oxide film 4 are formed on a semiconductor substrate 1, and then a polycrystalline silicon film 5 is deposited thereon and formed into a lower electrode 51 by patterning. A natural oxide film 10 is grown on the surface of the lower electrode 51, and the semiconductor substrate 1 is irradiated with ultraviolet rays 61 in an atmosphere of chloride to remove the natural oxide film 10, and then a silicon nitride film 6 is deposited on the lower electrode 51 through a CVD method. Furthermore, a silicon oxide film 7 is formed on the silicon nitride film 6, a polycrystalline silicon film 52 is deposited thereon and formed into an upper electrode 53 by patterning. Therefore, a sit icon nitride film 6 serving as a capacitor insulating film can be prevented from deteriorating in quality. |
