光学学报, 2016, 36 (3): 0331001, 网络出版: 2016-03-03
单层柱状结构薄膜体散射的理论研究
Theoretical Research on Volume Scattering of Thin Films with Single-Layer Columnar Structure
薄膜 体散射 一阶微扰理论 柱状结构因子 非均质性 thin films volume scattering first order perturbation theory columnar structure factor inhomogeneity
摘要
电子束蒸发的单层光学薄膜具有明显的柱状结构,薄膜内部折射率的变化较大,由此引起的体散射现象也较明显。基于一阶电磁微扰理论,建立了单层光学薄膜的体散射理论模型,分析了膜层厚度、入射光偏振态、柱状结构因子、非均质性对体散射的影响。研究了纯柱状结构下,电子束蒸发的单层二氧化铪(HfO2)薄膜体散射的角分布散射值(ARS)随着膜层厚度的变化规律,结果表明纯柱状结构HfO2 薄膜体散射的ARS 量级与表面散射完全非相关模型的ARS值相近,并且在特定的膜厚范围内,体散射的ARS值随着膜厚的增大而增大。对于非均质性薄膜,当非均质性一定时,体散射的ARS值随着膜厚的增大而增大;当膜层厚度一定时,体散射的ARS值随着非均质性绝对值的增大而减小。
Abstract
Single- layer optical film prepared by electron beam evaporation possesses remarkable columnar structure. The variation of its internal film refractive index is large, so the induced volume scattering phenomenon is relatively obvious. Based on the first-order electromagnetic perturbation theory, the volume scattering theory model of single- layer optical film is established. The effects on volume scattering caused by layer thickness, polarization state of incident light, columnar structure factor and inhomogeneity are analyzed. For optical films with pure columnar structure, the variation law between the volume angle resolved scattering (ARS) of single-layer hafnium oxide (HfO2) thin films prepared by electron beam evaporation and the layer thickness is established. The ARS magnitude of volume scattering for pure columnar HfO2 films is similar to that of the completely uncorrelated surface scattering model. Within a certain range of film thickness, the ARS value of volume scattering increases with the increase of film thickness. For inhomogeneous thin films, the ARS value of volume scattering increases with the increase of film thickness when the inhomogeneity is constant. When the layer thickness is constant, the ARS value of volume scattering will decrease the increase of the absolute value of the inhomogeneity.
吴晗, 张锦龙, 李刚正, 孙英会. 单层柱状结构薄膜体散射的理论研究[J]. 光学学报, 2016, 36(3): 0331001. Wu Han, Zhang Jinlong, Li Gangzheng, Sun Yinghui. Theoretical Research on Volume Scattering of Thin Films with Single-Layer Columnar Structure[J]. Acta Optica Sinica, 2016, 36(3): 0331001.