Cryopump hybrid frontal array
AssigneeEdwards Vacuum LLC
InventorJeffrey A Wells
Life of this patent
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Abstract
A cryopump comprises a refrigerator, a condensing array cooled by the refrigerator, a radiation shield surrounding the condensing array and cooled by the refrigerator. The radiation shield has a frontal opening covered by a frontal array that is also cooled by the refrigerator. The frontal array comprises louvers across an otherwise substantially open center region of the frontal opening and an orifice plate across an outer region of the frontal opening. The hybrid frontal array allows for pumping speeds approximating those of a louver frontal array but with flow control comparable to an orifice plate.
Claims13
A cryopump for evacuating a chamber comprising:
- a refrigerator;
- a condensing array cooled by the refrigerator;
- a radiation shield surrounding the condensing array and cooled by the refrigerator, the radiation shield having a frontal opening;
- and
- a frontal array across the frontal opening of the radiation shield, the frontal array cooled by the refrigerator and comprising:
- concentric louvers of increasing diameter across a center region of the frontal opening;
- and
- an orifice plate having orifices therein, through which gas flows form the chamber, across an outer region of the frontal opening, the orifice plate surrounding the concentric louvers at a central opening in the plate.
Dependencies are inferred from the claim text.