Understanding the effect of HF-based wet shallow etching on optical performance of reactive-ion-etched fused silica optics
Laixi Sun, Ting Shao, Xinda Zhou, Weihua Li, Fenfei Li, Xin Ye, Jin Huang, Shufan Chen, Bo Li, Liming Yang, Wanguo Zheng
Abstract
F to HF solution makes it possible to produce a high-quality optical surface with a high laser-induced damage threshold, which is strongly associated with the surface roughness and fluorescence defect density. Additionally, changing the HF-based etching depth over the range from 1 μm to 3 μm can affect the surface damage resistance and absorption performance of RIE-treated fused silica. The light-scattering results indicate that the point defect density plays an important role in the determination of the HF-based etching depth. Understanding these trends can enable the advantages of the combined technique of RIE and HF-based etching during the fabrication of high-quality fused silica optics.