Thickness and Optical Properties of Layers on Solid Supports

Thickness and Optical Properties of Layers on Solid Supports 

The construction of an optical model is required for data analysis to extract physical properties, including the optical constants and Aim thickness of the sample. The model is an idealized representation of a given sample that allows the expected optical properties of the Aim to be calculated the calculated values are then compared to experimental data. Finding the best match between the model 

The complex dielectric function, e = i — ie2, which describes the material properties is connected to the complex refractive index N for discussing optical propagation through e = N, vhth e = n — and = Ink. Eor absorbing media, k and 2 are positive. Ellipsometry allows direct measurements to be made of the refractive index (n) and the extinction coefficient (k). 

This possibility is extremely useful for the structural characterization of polymer blends. The optical properties of the polymer layer can be described by a so-caUed effective dielectric function, which is a suitable average of the dielectric functions of the two components. Three averaging effective medium approximation (EMA)s -the linear, Maxwell-Garnett and Bruggeman EMAs - are widely used for this purpose [9]. These approximations differ in their spectral densities for a given volume fraction. 

---