| 摘要 |
PROBLEM TO BE SOLVED: To provide an etching method in which a silicon nitride film can be etched with respect to a silicon oxide film and/or a polysilicon film by a method for generating no plasma in a chamber at a high selection ratio.SOLUTION: Disclosed is an etching method in which a processed substrate W having a silicon nitride film on the surface and also having a polysilicon film and/or a silicon oxide film provided adjacent to the silicon nitride film, fluorine-containing gas and Ogas are supplied into the chamber 40 in a state where at least Ois excited, and, as a result, the silicon nitride film is selectively etched with respect to the polysilicon film and/or the silicon oxide film. |
