Substrate processing apparatus, method of manufacturing semiconductor device, and recording medium

A substrate processing apparatus comprising:

• a transfer chamber including a transfer space in which a substrate loaded in from a substrate accommodation container is transferred;
• a gas circulation path connecting one end and another end of the transfer space;
• a fan provided in the gas circulation path or at an end part of the gas circulation path and configured to circulate an atmosphere in the transfer space and the gas circulation path;
• a loading port through which the substrate is loaded into the transfer space from the substrate accommodation container;
• a side surface opening provided on at least one side surface of both side surfaces putting therebetween a side surface of the transfer chamber provided with the loading port, among a plurality of side surfaces forming the transfer chamber, the side surface opening communicating with the transfer space;
• a door provided to close the side surface opening;
• a circulation duct fixed to the door and movable integrally with the door and provided to constitute the gas circulation path in a state where the door is closed;
• a buffer space above the transfer space, the buffer space constituting a portion of the gas circulation path and being in fluid communication with the transfer space via the fan;
• a sealer provided on at least one of (i) an edge of an upper end opening of the circulation duct or (ii) an edge of an opening of the buffer space that connects to the circulation duct;
• and
• wherein the circulation duct is connected to the buffer space via the sealer in a state where the door is closed.