| abstract |
A method for forming an insulating film includes a step of preparing a substrate, which is to be processed and has silicon exposed on the surface; a step of performing oxidizing to the silicon on the surface, and forming a silicon oxide thin film on the surface of the silicon; a step of performing first nitriding to the silicon oxide film and the base silicon thereof, and forming a silicon oxynitride film; and a step of performing first heat treatment to the silicon oxynitride film in N2O atmosphere. In such method, a step of performing second nitriding to the silicon oxynitride film may be further included after the first heat treatment, and furthermore, a step of performing second heat treatment to the silicon oxynitride film after the second nitriding may be included. |