Velson Nathan Van, Zobeiri Hamidreza, Wang Xinwei
Opt Express. 2020 Nov 9;28(23):35272-35283. doi: 10.1364/OE.403705.
In the Raman probing of multilayer thin film materials, the intensity of the measured Raman scattered light will be impacted by the thickness of the thin film layers. The Raman signal intensity will vary non-monotonically with thickness due to interference from the multiple reflections of both the incident laser light and the Raman scattered light of thin film interfaces. Here, a method for calculating the Raman signal intensity from a multilayer thin film system based on the transfer matrix method with a rigorous treatment of the Raman signal generation (discontinuity) is presented. This calculation methodology is valid for any thin film stack with an arbitrary number of layers with arbitrary thicknesses. This approach is applied to several thin film material systems, including silicon-on-sapphire thin films, graphene on Si with a SiO capping layer, and multilayer MoS with the presence of a gap between layers and substrate. Different applications where this method can be used in the Raman probing of thin film material properties are discussed.
在多层薄膜材料的拉曼探测中，所测量的拉曼散射光强度会受到薄膜层厚度的影响。由于入射激光和薄膜界面的拉曼散射光的多次反射产生的干涉，拉曼信号强度会随厚度非单调变化。在此，提出了一种基于转移矩阵法并对拉曼信号产生（不连续性）进行严格处理来计算多层薄膜系统拉曼信号强度的方法。这种计算方法对于具有任意层数和任意厚度的任何薄膜堆叠都是有效的。该方法应用于几种薄膜材料系统，包括蓝宝石上硅薄膜、具有SiO覆盖层的Si上石墨烯以及层与衬底之间存在间隙的多层MoS。讨论了该方法可用于拉曼探测薄膜材料特性的不同应用。
