Patent ID: 7981809

Claim:
A film formation method for a semiconductor process for forming a silicon oxynitride film on a plurality of target substrates held at intervals in a vertical direction inside a reaction chamber of a vertical film formation apparatus, the reaction chamber being defined by an inner wall surface consisting mainly of a material selected from the group consisting of quartz and silicon carbide, the method comprising: performing a pre-process of nitriding the inner wall surface of the reaction chamber by a pre-process gas until nitridation of the inner wall surface is saturated, while supplying ammonia gas as the pre-process gas into the reaction chamber without the target substrates loaded therein, and setting an interior of the reaction chamber at a first temperature and a first pressure, wherein the pre-process is arranged to supply the pre-process gas into the reaction chamber while not turning the pre-process gas into plasma, and the first temperature is set to be within a range of 800 to 1,050° C., and the first pressure is set to be within a range of 665 Pa to 100 kPa; and then, loading the target substrates into the reaction chamber, and performing a film formation process to form a silicon oxynitride film on the target substrates.