Complete characterization of rough polymorphous silicon films by atomic force microscopy and the combined method of spectroscopic ellipsometry and spectroscopic reflectometry

In this paper the results of the complete characterization of hydrogenated polymorphous silicon (pm-Si:H) films deposited onto silicon single crystal substrates performed by atomic force microscopy (AFM) and the combined method of spectroscopic ellipsometry and spectroscopic reflectometry are presented. This combined method is applied in the multi-sample modification. The experimental data are measured within the near-UV, visible and near-IR regions (190-1000 nm). For treating the experimental data the dispersion model recently formulated for amorphous chalcogenide films is employed. This model is based on the parameterization of the density of electronic states. Moreover, for the treatment of the experimental data the structural model containing the defects, i.e. roughness of the upper boundaries of the films, overlayers, transition layers and refractive index profile inhomogeneity is employed. The results of the characterization consist of the determination of the spectral dependences of the optical constants of the pm-Si:H films and the values of the parameters describing the defects of these films.