溶胶-凝胶法制备宽带减反膜

Preparation of nanoporous broadband antireflective coatings by sol-gel method

为了克服单层减反射膜剩余反射高,色彩还原性能差的缺点,需要制备宽带减反膜。纳米多孔SiO2薄膜可以实现很好的宽带减反效果。本文用光学薄膜设计程序模拟了光学参数的变化对薄膜光学性能的影响,优化了薄膜的光学参数。实验上通过酸碱两步法和溶胶 凝胶技术制备了折射率梯度的纳米多孔SiO2宽带减反膜。采用椭偏仪、FE SEM、紫外 可见分光光度计等方法研究薄膜的光学特性和表面形貌。结果表明实验制备的SiO2薄膜具有可控的纳米多孔结构,折射率在1.18～1.43之间可连续调节。形成的宽带减反膜在可见光区域的平均反射率仅为0.44%。

To overcome the shortcomings of single layer antireflective (AR) coatings, a broadband AR coating composed of nanoporous SiO2 was prepared to reduce the mean reflectance in the visible region and improve the chromatic balance quality. In this paper, based on the thin film optical theory, the effects of optical parameters on reflectance were discussed and optical parameters of the coating were optimized. Structure controlled silica sols were made from TEOS with a base/acid twostep catalytic process by solgel method. And the broadband antireflectance (AR) silica film was obtained by spincoating. The coating was characterized with ellipsometer, FESEM, and spectrophotometer, respectively. The results show that the coating has an excellent broadband AR property with the only 0.44% reflectance in the visible region(400～760nm).