梳状滤光片是一种特殊的非均匀光学薄膜器件, 其膜层折射率渐变分布结构使它与常规均匀光学薄膜相比具有更好的光学和机械性能。利用反应磁控溅射工艺, 改变沉积SiOx(0≤x≤2)膜氧化程度, 获得折射率从2.74逐渐变化到1.58(λ=1550 nm)的SiOx渐变折射率薄膜材料。通过调制膜层折射率振幅和引入膜层-外部介质折射率匹配层, 成功地设计并制备了具有较好光学性能的SiOx渐变折射率红外梳状滤光片光学薄膜器件。使用单一的硅溅射靶材, 通过改变氧化程度获得可变折射率材料的方法, 为特殊光学薄膜器件的制备提供了一种经济实用的工艺路线。

Rugate filter is a special inhomogeneous optical coating. The graded refractive-index profile makes it have better optical and mechanical properties than conventional homogeneous optical coating. The graded refractive index SiOx (0≤x≤2) coating materials with precisely controlled refractive index ranging from 2.74 to 1.59 (λ=1550 nm) are deposited by tuning its oxidation degree in reactive magnetron sputtering. Then high quality SiOx infrared rugate filters are successfully designed and fabricated by choosing proper refractive index amplitude apodization function and introducing refractive index matching layer on the interface, which provides a practical and economical technique for industrial fabrication of rugate filters.