超高精度离子束抛光工具设计与性能分析

Design and performance analysis of ultra-precision ion beam polishing tool

为了解决高精度光学修形问题,进行离子束抛光工具的设计与性能分析研究。通过开展离子束抛光工具设计方法的研究、聚焦离子光学系统结构设计和离子束流特性的分析,进行计算机仿真研究和中和器一体化设计;研制聚焦离子光学系统和中和器,并采用15mm和10mm的聚焦离子光学系统进行修形加工实验,将口径150mm的熔石英平面镜从初始面形误差RMS15.58nm修正到RMS0.79nm。结果证明了聚焦离子光学系统设计的有效性,一体化离子束抛光工具具有亚纳米精度的修形能力。

In order to solve the problem of ion beam figuring, the design and performance analysis of ultra-precision ion beam polishing tool was studied. The research on ion beam polishing tools design method, the structure design of a 3-grid focused ion optics system and the performance analysis of ion beam was covered. Based on the theoretic calculation and computer simulation, a focused ion optical system was developed. In this ion optical system, an integrated plasma bridge neutralizer was designed to fully neutralize ion beam extracted from ion source. Finally, a 150mm flat optics was figured by two designed focused ion optical systems with 15mm and 10mm output diameter. Figuring result shows that the contour error of this flat is decreased from 15.58nm RMS to 0. 79nm RMS. Result further demonstrates that the designed ion beam polishing tool is very efficient to optical ion beam figuring.