| 摘要 |
PROBLEM TO BE SOLVED: To monitor an operating condition adapted to vacuum processing in a vacuum device attached with a cryopump.SOLUTION: The cryopump evacuates gas from the vacuum chamber of the vacuum device performing the vacuum processing. The cryopump includes a refrigerator, a cryopanel cooled by the refrigerator, and a control unit controlling the operational frequency of the refrigerator so that the cryopanel is controlled to a target temperature. The control unit monitors the operational frequency for a first determination time when the operational frequency of the refrigerator reaches a first criterion, and monitors the temperature of the cryopanel for a second determination time shorter than the first determination time when the operational frequency reaches a second criterion corresponding to a load higher than the first criterion. |
