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In this paper the exact approach of the Rayleigh–Rice theory enabling us to calculate optical quantities of multi-layer systems with boundaries exhibiting slight random roughness is presented. This approach is exact in the sense that it takes into account the propagation of perturbed electromagnetic fields (waves) among randomly rough boundaries including all cross-correlation and auto-correlation effects. The restriction to the second order of perturbation, which is the lowest order that gives nonzero corrections to coherent waves (obeying the Snell’s law), represents the only approximation used in our calculations. It is assumed that the layers and the substrates are formed by optically homogeneous and isotropic materials. The formulae obtained in the theoretical part are used to investigate the influence of layer thicknesses and roughness parameters on reflectances and associated ellipsometric parameters of the selected numerical examples of a three-layer system. The presented approach represents the generalization of the exact approach for single-layer systems and the improvement of the approximate approach for multi-layer systems published earlier. The exact approach of the RRT has a substantial importance for the optical characterization of multi-layer systems occurring in applied research and optics industry applications.

The formulae enabling us to calculate the values of the ellipsometric parameters of randomly rough surfaces and very thin films with randomly rough boundaries with respect to the influence of the shadowing between the irregularities of roughness are presented. These formulae are derived within the scalar diffraction theory of light. The first formula allows the calculation of the ellipsometric parameters using a numerical method, while the second formula is the approximative one but it expresses the ellipsometric parameters in a closed form. The numerical analysis of both formulae is performed for several examples of randomly rough surfaces and thin films. Moreover, the comparison of the results achieved using both formulae respecting the shadowing and an earlier formula not including this effect is performed. The experimental data of two samples of the randomly rough silicon surfaces covered with very thin surface layers are interpreted using all the formulae mentioned. Using this experimental study, the correctness of both formulae taking into account the shadowing, is confirmed.

In this paper results of the optical characterization of double layers consisting of ZnTe and ZnSe thin films prepared by molecular beam epitaxy onto GaAs single crystal substrates are presented. For this optical characterization the optical method based on combining variable angle spectroscopic ellipsometry and near-normal spectroscopic reflectometry is used in the multi-sample modification applied within the spectral region 230–850 nm. Using this method the spectral dependences of the optical constants of the upper ZnTe thin films are determined within the spectral region mentioned above. Spectral dependences of the optical constants of the lower ZnSe thin films were determined within the spectral region 450–850 nm. Boundary roughness of these double layers and overlayers is respected. RMS values of the heights of the irregularities of the boundaries and thicknesses and optical constants of the overlayers are determined by means of the combined optical method as well. The uppermost boundaries of the dou...

In this paper formulae expressing the coherent reflectance, coherent transmittance and scattering losses of multilayer systems with correlated randomly rough boundaries derived within a certain approximation are presented. The theoretical approach employed for deriving these formulae is based on the scalar theory of diffraction of light. A brief numerical analysis of the formulae mentioned is performed for chosen rough multilayer systems. These formulae are also utilized for interpreting experimental data of samples of two chosen multilayers with rough boundaries. Moreover, in this paper formulae enabling us to estimate the errors in the optical quantities calculated using the approximate formulae are also presented.

A method of determination of the basic morphology parameters of rough metal surfaces with periodic and random components of surface roughness by means of laser light scattering is presented. The method is based on interpreting the angular distribution of the laser light intensity scattered from such surfaces. The theory of the method is based on the scalar theory of diffraction and basic theorems of data processing. The new, more general way of interpreting experimental data is specified. It can also be used for the analysis of samples with quasiperiodic and random components of surface roughness; this is the case when standard measurement by means of a stylus profilometer can give incorrect results.

In this theoretical paper, formulae for important optical quantities of single layers with slightly randomly rough boundaries are derived by means of a generalized Rayleigh–Rice theory. Thus the formulae for the specular reflectances and ellipsometric parameters of the layers mentioned are presented. The theoretical results are illustrated by a numerical analysis. Practical features implied by this analysis to be relevant from the experimental point of view are introduced as well. Moreover, relations expressing the flux of scattered light are presented.

In this theoretical paper, general formulae for evaluating the optical parameters that characterize homogeneous and inhomogeneous single layers formed by non-absorbing or weakly absorbing materials are presented. It is shown that these formulae can be used to realize a complete analysis of these layers by a simple method using spectroscopic reflectometry. The layers investigated with this method must be sufficiently thick for there to be several extrema in the spectral dependence of the reflectance describing each of these layers.