Unambiguous analytical inversion of multiple thickness ellipsometric data for an embedded nonabsorbing uniform layer

We give an unambiguous analytical solution of the inverse problem of multiple ellipsometric data, taken at different (arbitrary and preliminary unknown) thicknesses of an embedded nonabsorbing uniform layer. The solution uses all available data in the least square sense for the determination of the layer refractive index and then the corresponding thickness for each measured point is determined. Its usage is illustrated with treating experimental ellipsometric data for two systems. The error propagation analysis of the above solution shows its very high robustness to uncertainties in the input data.