A method for treating gastroesophageal reflux disease in a body of a mammal is provided. The method of forming a carbon-containing thin film includes the steps of introducing a substrate into a chamber, injecting hydrocarbon gas and at least nitrogen gas simultaneously into the chamber, and depositing a carbon-containing thin film including carbon and nitrogen on the substrate, thereby forming a carbon-containing thin film having high selectivity and uniform thickness. A transmittance correction coefficient map is generated by dividing a pattern formation region into a plurality of subregions, and determining a transmittance correction coefficient for each of the plurality of subregions. The fixture may further include a diffuser mounted to the enclosure to distribute light from the HID lamp in a uniform manner. As a result, recessed and raised areas are formed in the foil. Reliability of operation is improved with the provision of a pressure-limiting device with two lines arranged in parallel with two pressure-limiting valves each arranged in the same direction in series.