Load port and method for carrying wafers

A load port which is provided to be adjacent to a wafer carrying chamber installed in a clean room and configured to take in and out wafers between the wafer carrying chamber and a wafer storage container comprising a container main body and a lid, the load port comprising:

• a tabular portion which constitutes a part of a wall surface of the wafer carrying chamber and comprises an opening through which the wafer carrying chamber is opened;
• a mounting table on which the wafer storage container is mounted in such a manner that the lid of the wafer storage container faces the opening;
• a door section which is fitted in the opening, and drivable in such a manner that the door section is detached from the opening to enable opening and closing of the opening;
• a sucking tool which is installed in the door section, and capable of holding the lid by sucking the lid;
• a latch which is installed in the door section, drivable to unfix the container main body and the lid, and drivable to fix the container main body and the lid;
• a latch driving mechanism storage section which is provided to be adjacent to the door section in the wafer carrying chamber, and stores a latch driving mechanism to drive the latch therein, an air pressure in the latch driving mechanism storage section being settable to be equal to an air pressure in the clean room or lower than the air pressure in the clean room;
• and
• at least one of (i) an inner cap which stores the latch driving mechanism therein in the latch driving mechanism storage section, the inner cap being connected to an exhaust device, and the exhaust device enabling reduction of an air pressure in the inner cap to be lower than the air pressure in the clean room, and (ii) a hollow shaft section which supports the latch driving mechanism storage section, an inner space of the shaft section being connected to an inner space of the latch driving mechanism storage section, and an inside of the shaft section and an inside of the latch driving mechanism storage section being made airtight by the seal material and sealed to the wafer carrying chamber, and the exhaust device being connected to the shaft section enabling reduction of the air pressure in the latch driving mechanism to be lower than the air pressure in the clean room by decreasing an air pressure in the shaft section,
• wherein opening/closing the lid is enabled by unfixing the container main body and the lid by the latch and relatively moving the container main body to the sucking tool in a state where the lid is sucked and held by the sucking tool.