Dry air generation apparatus, dry air generation method, and substrate processing system

A dry air generation method comprising:

• providing a dry air generation apparatus including:
• a first heat exchanger and a second heat exchanger provided in an air flow path, and configured to cool air flowing in the air flow path to 0° C. or lower, thereby
• removing moisture contained in the air;
• a switching valve configured to switch a direction of air flowing in the first heat exchanger and the second heat exchanger;
• a first pipe connected to an air inlet;
• a second pipe connected to an air outlet;
• and
• a controller configured to control the first heat exchanger, the second heat exchanger, and the switching valve,
• wherein the first heat exchanger and the second heat exchanger are connected in series in the air flow path,
• the switching valve is provided between a side of the first pipe and the second pipe and a side of one end of the air flow path and a remaining end of the air flow path,
• the first heat exchanger is provided on the side of the one end of the air flow path, and
• the second heat exchanger is provided on the side of the remaining end of the air flow path,
• operating the second heat exchanger and stopping the first heat exchanger by the controller when a heat exchange efficiency of the first heat exchanger becomes equal to or lower than a predetermined efficiency in a state where the first heat exchanger is operated and the second heat exchanger is stopped;
• operating the first heat exchanger and stopping the second heat exchanger by the controller, when the heat exchange efficiency of the second heat exchanger becomes equal to or lower than the predetermined efficiency in a state where the first heat exchanger is stopped and the second heat exchanger is operated;
• controlling, by the controller, the switching valve to connect the first pipe to the remaining end of the air flow path and to connect the second pipe to the one end of the air flow path when operating the first heat exchanger and stopping the second heat exchanger;
• and
• controlling, by the controller, the switching valve to connect the first pipe to the one end of the air flow path and to connect the second pipe to the remaining end of the air flow path when stopping the first heat exchanger and operating the second heat exchanger.

A substrate processing system comprising:

• a low-temperature plate provided in a substrate processing apparatus that processes a substrate and having a temperature lower than room temperature;
• a support that surrounds at least a portion of the low-temperature plate to form a space;
• a dry air generation apparatus configured to generate a dry air;
• and
• a flow rate controller provided between the dry air generation apparatus and the space, and connected to the space by a pipe, the flow rate controller being configured to control a flow rate of the dry air generated by the dry air generation apparatus and supply the dry air into the space through the pipe,
• wherein the dry air generation apparatus includes:
• a first heat exchanger and a second heat exchanger provided in an air flow path, and configured to cool air flowing in the air flow path to 0° C. or lower, thereby removing moisture contained in the air;
• a switching valve configured to switch a direction of air flowing in the first heat exchanger and the second heat exchanger;
• a first pipe connected to an air inlet;
• a second pipe connected to an air outlet;
• and
• a controller configured to control the first heat exchanger, the second heat exchanger, and the switching valve,
• wherein the first heat exchanger and the second heat exchanger are connected in series in the air flow path,
• the switching valve is provided between a side of the first pipe and the second pipe and a side of one end of the air flow path and a remaining end of the air flow path,
• the first heat exchanger is provided on the side of the one end of the air flow path, and the second heat exchanger is provided on the side of the remaining end of the air flow path,
• wherein the controller is configured to:
• stop the first heat exchanger after a predetermined time elapses after the second heat exchanger is operated when heat exchange efficiency of the first heat exchanger becomes equal to or lower than a predetermined efficiency,
• stop the second heat exchanger after a predetermined time elapses after the first heat exchanger is operated when heat exchange efficiency of the second heat exchanger becomes equal to or lower than the predetermined efficiency,
• control the switching valve to connect the first pipe to the remaining end of the air flow path and to connect the second pipe to the one end of the air flow path when operating the first heat exchanger and stopping the second heat exchanger, and
• control the switching valve to connect the first pipe to the one end of the air flow path and to connect the second pipe to the remaining end of the air flow path when stopping the first heat exchanger and operating the second heat exchanger.