采用溶胶凝胶方法在K9玻璃基片上镀制了SiO₂增透膜,并对其中一些样品进行了氨处理。分别采用原子力显微镜、红外光谱仪、椭偏仪、透射式光热透镜测试了氨处理前后薄膜的微观表面形貌、化学结构、折射率和弱吸收。实验结果表明:经氨处理后薄膜的孔隙率从0.73降低到0.63,其弱吸收从67.88×10^-6增加到74.58×10^-6,薄膜的激光损伤阈值从处理前的18.0J/cm²降低到16.9J/cm²。考虑到氨处理能提高SiO₂增透膜的机械性能,实际应用中应根据需要折中处理。

The sol-gel silica films on K9 glass substrates were prepared with the dip method, and some of them were treated in saturated ammonia gas. Microcosmic surface morphology, chemical structure, refractive index and weak absorption of the films before and after ammonia treatment were respectively measured by Atomic Force Microscopy (AFM), infrared spectrophotometer, ellipsometer and transmission photo-thermal lens. The experimental results indicated that the porous ratio of the films decreased from 0.73 to 0.63 after ammonia treatment, and the weak absorption increased from 67.88×10^-6 to 74.58×10^-6. The Laser-induced Damage Threshold (LIDT) of silica films decreased from 18.0 J/cm² to 16.9 J/cm² after ammonia treatment. Considering the improved mechanical property of films with ammonia treatment, a trade-off is always needed between mechanical property and LIDT according to the requirement in practice.