摘要：The back-sputtering effect of an electric thruster used in a vacuum chamber has an adverse effect on the thruster, vacuum chamber and experimental equipment. An anti-sputtering target （AST） can extend the operating life of the vacuum chamber by reducing the back-sputtering deposition effect. Vacuum chambers used in international facilities have successfully incorpo- rated ASTs. To improve an AST＇s performance, a double layer structure AST based on the plume effects experimental system （PES） was designed. The structure of primary-end of the AST was designed as a flat while the secondary end was designed as a shutter to resolve factors such as service life, back flow rate of the sputtered material, economy and system security. To veri- fy the effects of the double layer AST, the sputtering effects of the AST with and without the secondary-end were evaluated by a DSMC-PIC algorithm. Additionally, the experimental verifications of the bare chamber and the target were performed. The results indicate that the secondary end graphite sheets can reduce the back flow yield approximately 50%. The design of the double layer AST can be introduced as a reference for the design of an anti-sputtering target.

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