Cryopump control apparatus, cryopump system, and method for monitoring cryopump

Abstract

A cryopump comprises a cryopanel that cools and thus condenses or adsorbs gas, and a pump housing that contains the cryopanel. a regeneration process of the cryopump includes a basic purge process, an evacuation processes, and an optional purge process that is executed additionally if required. The optional purge process includes one or more gas purge steps. In a cryopump control apparatus that controls the cryopump, a deterioration evaluation unit determines whether a re-purge number, which is the total number of gas purge steps that are required to be executed in one regeneration process, reaches a deterioration evaluation criteria number.

Description

Technical field [0001] The invention relates to a vacuum technology, in particular to a cryopump control device, a cryopump system and a cryopump monitoring method. Background technique [0002] The cryopump is a vacuum pump that realizes a clean high-vacuum environment. For example, the cryopump is used to maintain a high vacuum in a vacuum chamber used in a semiconductor circuit manufacturing process. The cryopump condenses or adsorbs and accumulates gas molecules through a cryoplate cooled to an ultra-low temperature by a refrigerator, thereby discharging gas from the vacuum chamber. [0003] If the cryoplate is covered with gas condensed into a solid or the adsorbed gas is close to the maximum adsorption capacity of the cryoplate's adsorbent, the exhaust capacity of the cryopump will decrease. Therefore, the regeneration process of removing the condensed gas to the outside of the cryopump is appropriately performed. [0004] In the regeneration process, the temperature of the c...

AI Technical Summary

Problems solved by technology

[0010] However, the degree of deterioration or contamination of each component of the cryopump varies greatly depending on the conditions of use, so it is not possible to uniformly determine the appropriate maintenance timing

[0011] Due to the increase in the downtime of the vacuum chamber due to the maintenance of the cryopump, and the decrease in the operation rate of the vacuum processing system, it is necessary to minimize the frequency of maintenance at the manufacturing site where productivity is important.

[0012] However, when deterioration of components etc. proceeds earlier than expected, cryopump failure may occur unexpectedly before periodic inspection or overhaul is carried out, and downtime of vacuum equipment may also occur suddenly

This situation has a negative impact on the manufacturing plan

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