摘要 |
A method is provided for using a film formation apparatus including a process container having an inner surface, which contains as a main component a material selected from the group consisting of quartz and silicon carbide. The method includes performing a film formation process to form a silicon nitride film on a product target substrate inside the process container, and then, unloading the product target substrate from the process container. Thereafter, the method includes supplying an oxidizing gas into the process container with no product target substrate accommodated therein, thereby performing an oxidation process to change by-product films deposited on the inner surface of the process container into a composition richer in oxygen than nitrogen, at a part of the by-product films from a surface thereof to a predetermined depth. |