环形抛光中频误差的计算模拟

Calculation and simulation on mid-spatial frequency error in continuous polishing

通过建立环形抛光的去除模型,从理论上分析了转速比、槽形、元件摆动对于抛光结果的影响,并分析了中频误差产生的原因。模拟结果表明:转速比的差异会产生较大的低频误差,而中频误差会随着低频误差的降低而降低;槽形是中频误差的主要来源,复杂的非对称不规律槽形使抛光路径复杂化,降低中频误差;同时元件的小幅度摆动能够使抛光更加均匀,减小定心式抛光造成的元件表面规则状纹路结构,从而有效减小元件的中频误差。

Based on theoretical model of continuous polishing, the influence of processing parameters on the polishing result was discussed. Possible causes of mid-spatial frequency error in the process were analyzed. The simulation results demonstrated that the low spatial frequency error was mainly caused by large rotating ratio. The mid spatial frequency error would decrease as the low spatial frequency error became lower. The regular groove shape was the primary reason of the mid-spatial frequency er ror. When irregular and fitful grooves were adopted, the mid-spatial frequency error could be lessened. Moreover, the workpiece swing could make the polishing process more uniform and reduce the mid-spatial frequency error caused by the fix-eccentric plane polishing.