As 2 S 3 :Cd films with nominal Cd content x up to 4 at.% were prepared by thermal evaporation. Their amorphous structure is confirmed by Raman spectroscopy. The film surface roughness estimated from atomic force microscopy does not exceed 1 nm. Energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy show a strong decrease of Cd content with the film depth. Peaks of CdS longitudinal optical phonon and its overtones emerging in the Raman spectra of films with x ! 2 at.% Cd are the evidence for the laser irradiation-induced formation of CdS crystallites in the As 2 S 3 :Cd films. The downward shift of the CdS Raman peak frequencies is mainly explained by tensile strain undergone by the CdS crystallites in the films caused by material transfer from the laser spot due to the photoplastic effect.

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Amorphous Zn-doped As2Se3 films with a nominal zinc content x up to 10 at.% were prepared by thermal evaporation. Their structure is characterized by atomic force microscopy (AFM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray photoemission spectroscopy (XPS), and Raman spectroscopy. The AFM data show a considerable increase of the film surface roughness for films with x > 5 at.%. A strong gradient of the Zn content decreasing into the film depth is confirmed by the EDX and XPS data. Heavily Zn-doped (above 7 at.%) As2Se3 films reveal photostructural changes in the course of the Raman measurements. New Raman features are attributed to TO and LO vibrations of ZnSe nanocrystallites formed in the film under laser illumination. Depending on the laser wavelength and power density, the ZnSe nanocrystallites can experience tensile strain in the film due to a non-thermal photoplastic effect in the As2Se3 film resulting in a partial removal of the material from the laser spot. The tensile strain value, estimated from the TO and LO phonon frequency shift, is shown to reach up to 2.9 GPa.

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