We investigate the nanoscale damage precursors that will cause laser damage initiation on fused silica surface during KOH-based wet etching. Some nanoscale damage precursors, like impurity contamination and chemical structure defects on different etched surface with a KOH solution, are explored through a variety of testing methods at nanoscale spatial resolution. The etched surface roughness and photothermal absorption level are also studied. The results show that KOH-based etching can keep a good surface roughness, reduce impurity contamination significantly, and thus decrease surface photothermal absorption level. However, it can mitigate little chemical structure defect and has a risk of secondary pollution induced by residual deposition such as K₂SiO₃. The work can be a reference on using KOH-based wet etching technology to mitigate nanoscale damage precursors of fused silica ultraviolet optics.

中文翻译：

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KOH溶液中湿法腐蚀对熔融石英纳米损伤前体的影响

我们研究了纳米损伤前驱物，该损伤前驱物会在基于KOH的湿法蚀刻过程中引起熔融石英表面的激光损伤引发。通过各种测试方法在纳米级空间分辨率下探索了一些纳米级损伤前体，例如不同的腐蚀表面（使用KOH溶液在不同的蚀刻表面上的杂质污染和化学结构缺陷）。还研究了蚀刻的表面粗糙度和光热吸收水平。结果表明，基于KOH的蚀刻可以保持良好的表面粗糙度，显着减少杂质污染，从而降低表面光热吸收水平。但是，它几乎可以减轻化学结构缺陷，并具有由残留沉积物（例如K ₂ SiO _3）引起的二次污染的风险。。该工作可以为使用基于KOH的湿法蚀刻技术减轻熔融石英紫外光学器件的纳米级损伤前体提供参考。