| 摘要 |
PURPOSE:To prevent the generation of crystal defects and reduce the difference of pattern conversion by a method wherein the first oxide film, first nitride film, second oxide film, and second nitride film are successively formed, and an element isolation region is formed by thermal oxidation after the films other than at the lowermost layer are patterned. CONSTITUTION:A thermal oxide film 12 is formed on an Si substrate 11, and thereafter the nitride film 13, oxide film 14, and nitride film 15 are successively formed on this oxide film 12 by e.g. a CVD method. Afterwards, with a photo resist as a mask, the films 15, 14, and 13 are patterned respectively. Then, the thick oxide film (element isolation region) 16 is formed by selective oxidation of the substrate 11 by thermal oxidation. |
