Patent ID: 9404486
Filing Date: 2016-08-02
CPC Classification: F04B

Claim Text:
1. A cryopump comprising: a radiation shield comprising a shield front end that defines a shield opening, a shield bottom portion that faces the shield opening, and a shield side portion that extends from the shield front end to the shield bottom portion; and a cryopanel assembly configured to be cooled to a temperature that is lower than that of the radiation shield, the assembly comprising a plurality of cryopanels arranged along a direction toward the shield bottom portion from the shield opening, wherein the plurality of cryopanels comprises: a first cryopanel comprising a first inner end portion and a first outer end portion that is directed to the shield side portion; a second cryopanel comprising a second inner end portion and a second outer end portion that is directed to the shield side portion, wherein a distance from the shield opening to the second inner end portion is longer than a distance from the shield opening to the first inner end portion, wherein a distance from the shield opening to the second outer end portion is longer than a distance from the shield opening to the first outer end portion, and wherein the distance from the shield opening to the second outer end portion is shorter than the distance from the shield opening to the first inner end portion, wherein each of the plurality of cryopanels comprises an inclined area that is inclined such that the inclined area is away from the shield opening at a site close to a central axis of the radiation shield and is close to the shield opening at a site far from the central axis, and wherein at least half of a width of the cryopanel in a radial direction from the central axis corresponds to the inclined area.