Patent ID: 8875523
Filing Date: 2014-11-04
Classification: F04B

Abstract:
1. A cryopump for use in evacuation of a beam path in a beam irradiating apparatus, the apparatus configured to irradiate a beam to a target, the cryopump comprising: a cryopanel configured to capture gas molecules on a surface thereof; a refrigerator configured to cool the cryopanel; and a control unit configured to receive a control signal from the beam irradiating apparatus representing an operation mode thereof and to control the refrigerator based on the control signal, wherein the operation mode includes an irradiation mode for irradiating a beam to a target and an idle mode for diverting the beam away from the target or keeping the beam with a level weaker than that of the irradiation mode, wherein the control unit controls the refrigerator such that the cryopanel is cooled to a cooling temperature at which the gas molecules are held in both the irradiation mode and the idle mode, wherein the control unit allows the cooling temperature in at least a part of a period of the idle mode to be higher than that of the irradiation mode.