【摘要】 提出了一种同时测量强吸收衬底上薄膜厚度和折射率的方法。对生长于强吸收衬底上的透明薄膜,提出在该薄膜上镀一层薄金属,形成金属-薄膜-强吸收衬底的类波导结构。由于小角度入射光在强吸收衬底上具有较强的反射率,使该结构可容纳一系列共振模。利用自由空间耦合技术和导出的共振模模式本征方程,同时确定透明薄膜的厚度和折射率。实验中测量了硅衬底上制备的聚甲基丙烯酸甲酯(PMMA)薄膜的折射率和厚度,测量的相对误差均小于10-3。该方法具有简便、可靠、可测量任意折射率薄膜的优点。更多还原

【Abstract】 A measuremant method of thickness and refractive index of film grown on the strong absorption substrate is proposed.A thin metal layer is deposited on a transparent film which is grown on a strong absorption substrate.As a result,an analogue waveguide configuration of metal-transparent film-absorption substrate,which can accommodate a series of resonant modes,is formed due to a bigger reflectivity on the absorption substrate for the small angle of incidence.Based on the free-space coupling technique and the eigenvalue equation of the resonant modes derived by the standard electromagnetic field theory,the thickness and refractive index of the transparent film are simultaneously determined with a relative error of 1×10~-3.The proposed method is simple and reliable,and can be used for the film with different refractive indexes.更多还原