| 摘要 |
PURPOSE:To prevent a substrate from damaging by etching in case of etching a silicon nitride film by providing a silicon oxide film between the substrate and the silicon oxide film. CONSTITUTION:A silicon oxide film 2 is formed on the surface region of a semiconductor substrate 1. The first silicon nitride film 3 is formed on the film 2, and etched to form a predetermined pattern having an inversely tapered shape. A metal film 5 is formed by depositing on the surface which includes a pattern. With the film 5 as a mask the oxide film 3' of the end of the film 3 is etched. The side wall of the etched film is coated with the second silicon nitride film 4. The film 4 is selectively etched to allow the film 4 to remain on the side wall of the oxide film. A heat treatment is executed in oxygen, hydrogen or mixed gas atmosphere to form a silicon oxide film 6. Thus, it can prevent the substrate 1 from damaging by etching in case of etching the film 4. |
