Cryopump and Vacuum Pumping Method
AssigneeSumitomo Heavy Industries, Ltd.
InventorHidekazu Tanaka
Life of this patent
Estimating the term…
Abstract
A cryopump 10 includes: a first cryopanel including a radiation shield 18 having a shield opening 20 and a louver 23 arranged in the shield opening 20; a second cryopanel 24 surrounded by the first cryopanel; and a refrigerator 14 configured to cool the first cryopanel to a first cooling temperature and to cool the second cryopanel to a second cooling temperature lower than the first cooling temperature. A rough surface 42 is formed on the louver 23.
Claims7
A cryopump comprising:
- a first cryopanel comprising a radiation shield having an opening and a baffle arranged in the opening;
- a second cryopanel surrounded by the first cryopanel;
- and
- a refrigerator configured to cool the first cryopanel to a first cooling temperature and to cool the second cryopanel to a second cooling temperature lower than the first cooling temperature, wherein
- a rough surface is formed on the baffle.
A vacuum pumping method for pumping a gas including a process gas and moisture by a cryopump in a vacuum process in which supply of the process gas to a vacuum chamber and stop of the supply are repeated, comprising:
- cooling a baffle provided in an inlet of the cryopump to form an ice layer in contact with a rough surface of the baffle such that rerelease of process gas molecules is suppressed during the stop of the supply, the process gas molecules that have been captured by the ice layer due to a cryotrapping phenomenon during the supply of the process gas.
Dependencies are inferred from the claim text.