In the optical processing, ion beam processing has been used widely for the advantages of highly-precision, less pollution
and no stress and distortion. In order to analysis the preferential sputtering phenomenon, that Ar ion processing SiO2
mirror is considered as an example, which is commonly done in ion beam processing. In order to improve the processing
precision, the influence of Ar ion incident angle and incident energy on SiO2 sputtering yield is analyzed in the case of
considering the preferential sputtering phenomenon. By using the TRIM 2008 software, the sputtering situation of two
elements of Si and O are simulated. The sputtering yield rate of the two elements is always a certain proportion, and the
ratio is not related with the incident angle and it almost stays the same in a certain energy range. So, the SiO2 can be
thought as a whole when considering its sputtering yield, which equals to the sum of Si and O sputtering yield.