Method for cleaning first mirror in situ through radio frequency plasma

Abstract

The invention provides a method for cleaning a first mirror in situ through radio frequency plasma. The method is characterized in that a coaxial cable is adopted to introduce a radio-frequency power supply into a sample exchange chamber connected with a Tokamak device vacuum chamber, and the radio-frequency power supply is connected to the first mirror; the first mirror is pushed to the Tokamak device vacuum chamber through a sample conveying rod in the sample exchange chamber; the Tokamak device vacuum chamber is filled with a working gas, and the radio-frequency power supply is turned on to apply radio-frequency voltage to the first mirror; the radio-frequency power is gradually improved, a radio-frequency matcher is regulated to enable the radio-frequency reflection power to be zero, and the radio frequency plasma is generated on the surface of the first mirror; the self bias of the first mirror is regulated according to the category of surface deposition layers of the first mirror, and the surface deposition layers of the first mirror are cleaned through plasma sputtering; after cleaning for a certain time, the radio-frequency power supply is turned off and cleaning is stopped; and the first mirror sample is taken out through the sample exchange chamber and the sample conveying rod, and subsequent characterization is carried out.

Description

technical field [0001] The invention relates to a magnetic confinement nuclear fusion technology, in particular to a method for in-situ cleaning of a first mirror by radio frequency plasma. Background technique [0002] In the tokamak type magnetic confinement nuclear fusion device, the optical diagnosis system is one of the important means to monitor the plasma operation status and ensure the safety of the device. With the increase of plasma parameters and device size, the first mirror is used to replace the traditional optical glass window to avoid the damage of optical components caused by plasma radiation and ensure the accuracy and effectiveness of diagnostic signals. The first mirror directly faces the plasma, and suffers from the bombardment of high-energy particles from the plasma, the deposition of wall treatment elements, and the redeposition of sputtered wall materials. The impurity deposition layer appears on the surface, and the deposition layer absorbs and inte...

AI Technical Summary

Problems solved by technology

However, this technology has not yet realized the tokamak ultra-high vacuum and in-situ cleaning work in a strong magnetic field environment.

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