Cryopump

Abstract

A cryopump includes a radiation shield provided with a main inlet at one end thereof and a sub-inlet in a side thereof; and a cryopanel assembly cooled to a temperature lower than that of the radiation shield. The cryopanel assembly includes an upper structure having at least one cryopanel and a lower structure having at least one cryopanel. The upper and lower structures are arranged inside the radiation shield along a direction away from the main inlet. A frost accommodating space connected to the sub-inlet may be arranged between the upper and lower structures such that an amount of captured gas on an upper end cryopanel of the lower structure is greater than an amount of captured gas on a lower end cryopanel of the upper structure.

Dependencies are inferred from the claim text.