Spital distribution of sputtered atoms of molybdenum material measuring by the aluminum arch array

The grid assembly is the key component of the ion thruster and directly affects the performance and lifetime of the thruster. In the ion thruster, the grid material is sputtered and ejected in different directions under the bombardment of low-energy CEX ions, leading to a redeposition of the sputtered atoms on the grids surface and a deviation of the standard working performance of grid assembly. In this paper, the differential sputtering yield of Mo grid material at different locations is made by using the aluminum arch array. The spatial distribution characteristics of sputtered atoms as a function of azimuthal and injection angles are determined and compared with the standard QCM method. The results show that the differential sputtering yield distributions obtained by the aluminum arc array are in good agreement with the QCM method. Furthermore, the effect of incident ion species and ion energy on the spatial distribution characteristics of Mo sputtered atoms are compared. It is found that, the sputtering yield of Mo under Xe incidence is the lowest among Xe, Kr, and Ar incidence. The related results can be used to determine the deposition orientation of sputtered atoms and provide a practical basis for the establishment of a redeposition simulation model for grid assembly.