| 摘要 |
PROBLEM TO BE SOLVED: To prevent damage of a device and the degradation of a degree of vacuum at emergency stop of an air bearing for vacuum by stopping air supply or exhaust in order from a high atmospheric pressure place of an air supply or exhaust place from a fixed part after stopping a linear motor for moving a movable part when stopping an air bearing device. SOLUTION: A movable part 2 is opposed at an interval of about 5μm to a fixed part 1, and air or nitrogen under about 4 atmospheric pressure is blown out of an air supply groove 31. Air supply grooves 41, 51 are respectively connected to a dry pump and a turb-molecular pump via bellows to exhaust gas blown out of the air supply groove 31. A stage is moved by using a linear motor having the stage fixed to the movable part 2. When an error is caused, an air supply value 33 is closed to stop the blow-off of the gas. Next, degree of vacuum of an air exhaust groove 41 is measured, and when the degree of vacuum reaches a certain preset value, an air exhaust valve 43 is closed to stop air exhaust in the dry pump to thereby shorten stopping time of an electron beam plotting device by the degradation of a degree of vacuum in a vacuum chamber.
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