Substrate processing apparatus, method of processing substrate, method of manufacturing semiconductor device, and gas rectifier

Abstract

There is provided a configuration that includes at least one port that is provided in a process container in which a substrate is accommodated and heat-treated, the port providing an optical path that penetrates an interior of the process container and an exterior of the process container; an optical window that is mounted to the port and transmits light while maintaining the port airtight; a purge gas supplier that is disposed inside the process container and provides a purge gas to an inner surface of the optical window; and a partition that guides the purge gas from the purge gas supplier to the optical window. Figure 1