离子发动机栅极材料差分溅射产额分布特性仿真

Simulation on the distribution characteristics of differential sputtering yields on ion engine grid materials

针对离子发动机栅极溅射原子空间分布不明确导致栅极腐蚀模型预测偏差大的问题,采用SDTrimSP程序模拟离子轰击栅极材料的溅射过程;系统研究离子入射能量、入射角度以及离子种类对钼栅极材料差分溅射产额的影响。发现正入射条件下的差分溅射产额仿真结果与实验具有较好的一致性。重点关注斜入射条件下差分溅射产额在不同方位角下的分布轮廓,并通过Modified-Zhang公式对差分溅射产额进行拟合,以拟合结果作为材料边界条件输入溅射腐蚀—再沉积模型,较为真实地模拟了栅极材料的腐蚀过程。以上研究可为离子发动机栅极组件腐蚀形貌的精确预测提供参考。

In view of the unclear spatial distributions of sputtered atoms from ion engine grid,which leads to significant deviations in grid erosion modeling predictions,the SDTrimSP program was used to simulate the sputtering process of ions bombarding the grid materials.The study systematically investigated the impact of ion incident energy,incident angle,and ion species on the differential sputtering yields of molybdenum grid materials.Under normal incidence,the simulated differential sputtering yields were found to be in good agreement with experimental data.Special attention was given to the distribution profiles of differential sputtering yields at different azimuthal angles under oblique incidence.The Modified-Zhang formula was used to fit the differential sputtering yields.The fitting results were applied as material boundary conditions in the erosion-redeposition model,offering a more realistic simulation of the grid materials’erosion process.This approach may provide a reference for the accurate prediction of the erosion morphology of ion engine grid components.