Process parameters optimization for fused silica optics by megasonic assisted chemical etching

The traditional static etching method was improved, a new megasonic-assisted chemical etching method of optical components was proposed. The megasonic assisted chemical etching effects were compared with those of static etching. Considering the effects of the ratio of the etching solution, etching time, active agent types and megasonic power, the etching process parameters were optimized. The results showed that megasonics assisted chemical etching was better for all kinds of impurities removal than the manual scrubbing, and it had a higher etching rate than the traditional static etching, its etching liquid could enter into the micro-cracks, which was difficult for the traditional static etching, thus the etching effect was more obvious and laser damage threshold could be further improved.