二氧化硅减反膜的结构疏松, 且胶粒表面存在大量羟基, 膜层极易吸附环境中的水分和有机蒸气, 透射比稳定性较低。为了改善原有减反膜的环境稳定性, 以3, 3, 3-三氟丙基三甲氧基硅烷和3, 3, 3-三氟丙基甲基二乙氧基硅烷为掺杂剂, 正硅酸乙酯为前躯体, 采用溶胶-凝胶法制备了两个系列的SiO2减反膜。结果表明, 含氟硅氧烷改性的系列膜层的疏水性能均得到显著增强。CF3-CH2-CH2-Si或CF3-CH2-CH2-Si-CH3质量分数在0.40%～1.5%的范围内时, 二氧化硅膜层的减反效果较好。掺入含氟硅氧烷在一定质量分数时, 膜层的抗激光损伤性能受到的影响不大。10-3 Pa高真空环境的实验表明, 膜层的稳定性有较大提高, 含氟硅氧烷改性延长了减反膜的使用寿命。

Antireflective (AR) coatings prepared from colloidal suspensions of silica are porous and quite polar due to residual Si-OH. So the silica coatings readily absorb water or organic vapor which is detrimental to the optical performance. In order to improve the stability of AR coating, two series of antireflective coatings are prepared by sol-gel process with tetraethoxysilane as a precursor. All of them are modified with trimethoxy (3,3,3-trifluoropropyl)-silane and diethoxymethyl (3,3,3-trifluoropropyl)-silane. Experimental results show that hydrophobic performance of the coatings is enhanced significantly. The anti-reflectivity of the coating is high when the mass fraction of CF3-CH2-CH2-Si or CF3-CH2-CH2-Si-CH3 is between 0.40%～1.5%. At a certain mass fraction of fluorine-containing siloxane, the performance of high laser damage threshold is not affected obviously. A series of tests are carried out by exposuring the coatings to vapor contamination in 10-3 Pa vacuum chamber. The test results indicate that the stability and life of AR coatings are improved greatly.