| 摘要 |
PROBLEM TO BE SOLVED: To reduce the step on a layer insulation film and lessen the variation of thickness of the resist film on this insulation film to obtain a high reliability device allowing following steps of process to be well executed. SOLUTION: Ammoniacal hydrolysis is applied to BPTEOS to be a layer insulation film 13, thereby forming a low-concn. impurity layer 14 on the surface of the film 13. Using a resist 15, holes are formed for memory cells. Using the resist 15 as a mask, the film 13 is isotropically wet etched. This etching increases the side etching quantity at the lower part of the resist 15 about 4 times, thereby reducing the step on the insulation film 13. Thus a method of manufacturing high-reliability semiconductor devices is obtained. |
