Amorphous chalcogenide thin films of Ge25S75 composition have been deposited by spin-coating technique. Optical properties of thin films were investigated by spectroscopic ellipsometry in UV-MIR spectral range. Obtained results prove increase of thin films refractive index in the transparent region and decrease of their thickness with increasing annealing temperature implying densification of the glass structure. Short wavelength absorption edge is shifting to lower energies (red shift) with increasing annealing temperature. Decreasing organic molecules content with increasing temperature of annealing was observed in MIR part of extinction coefficient and verified by Raman spectroscopy and EDS. Raman spectra also gave evidence of thermo-induced structural polymerization and decomposition of organic salts molecules yielding thin films with structure similar to the structure of the source bulk glass.

Crystal growth in the surface of selenium bulk samples and in selenium thin films of different thicknesses has been studied under isothermal conditions using different microscopy techniques (optical, infrared, and scanning electron microscopy). The structure of the formed crystals is described with respect to previous publications focused on crystal growth in selenium thin films and bulk samples. Crystal growth rates were obtained from the linear dependence of crystal sizes on annealing time. Such behavior assumes that crystal growth is driven by liquid–crystal interface kinetics. The crystal growth rates found in the surface of bulk samples are comparable with those found in thin films and a few orders of magnitude higher than previously published growth rates of volume crystals formed in selenium undercooled melts. The crystal growth rates were scaled with the viscosities to analyze the Stokes–Einstein relation. A relatively high decoupling between the crystal growth rate and viscosity occurs in the studied samples of amorphous selenium. Therefore, the standard screw dislocation growth model is corrected for the decoupling, which provides a satisfactory description of the crystal growth rate over a wide temperature range.

Chalcogenide glass thin layers are useful to many practical applications especially for the fabrication of infrared (IR) optical elements. In comparison to the conventional vacuum deposition methods of their preparation, recently chemical methods such as spin coating are gaining attention. They involve dissolution of the source bulk glass in appropriate solvent and then depositing its thin layer. Chemical processes occurring during the glass dissolution and thin layer deposition determine the physicochemical properties of deposited thin layers. The structure of chalcogenide bulk glasses (As x S 100-x , where 30  x  40) and their solutions in n-butylamine has been studied in this work by Raman spectroscopy. From the composition and time dependence of Raman spectra of solutions the mechanism of arsenic-sulfur glass dissolution involving the reaction of aliphatic amine solvent with homopolar S-S bonds is proposed and the presence of alkyl ammonium arsenic sulfide salts in thin layers is established.

This paper reports the dry and wet synthetic procedures and characterization by Raman spectroscopy of amorphous arsenic sulfide reference pigments. Reference spectra of two amorphous materials obtained by wet process methods and four dry process references of amorphous arsenic sulfide pigments of known composition are presented and discussed.While all materials present a main band characteristic for the amorphous pigment centered on 341 cm −1 , additional small contributions indicate the presence of sulfur, arsenic oxide, and crystalline nano phases embedded in the amorphous matrix. Although only the broad 341-cm −1 peak is necessary to identify the arsenic sulfide as an amorphous material, the smaller additional features allow for the characterization of the various manufacturing processes and initial materials used. In ideal conditions, these small features also enable to assess the As/S ratio of the studied amorphous arsenic sulfide pigments based on their relative intensity. In this context, the latter reference spectra were used to characterize the amorphous arsenic sulfide pigments and their arsenic to sulfur elemental composition in four 18th-to 20th-century historical samples and compared with scanning electron microscopy with energy dispersive X-ray semiquantitative analyses. The identification of the amorphous arsenic sulfide used in these historical samples was compared with the description of the manufacturing processes reported in historical sources of the time, allowing for a better understanding of the evolution of the amorphous arsenic sulfide pigments manufacturing methods.

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Thin amorphous films of Ge20Sb5S75 composition have been deposited by spin-coating and vacuum thermal evaporation techniques. Their optical properties were investigated by spectroscopic ellipsometry in UV-NIR spectral region. We report on the comparison of thermoand photo-induced changes in optical parameters, structure and chemical resistance of studied samples. Induced changes of films structure connected with changes of chemical stability were exploited for their surface structuring by photolithography and electron beam lithography.

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Thermoelectric effects are one of the promising ways to utilize waste heat. Novel approaches have appeared in recent decades aiming to enhance thermoelectric conversion. The theory of energy filtering of free carriers by inclusions ranks is among the latest developed methods. Although the basic idea is clear, experimental evidence of this phenomenon is rare. Based on this concept, we searched suitable systems with stable structures showing energy filtering. Here, we report on the anomalous behavior of Cr-doped single-crystal Bi 2 Se 3 that indicates energy filtering. The solubility of chromium in Bi 2 Se 3 was studied, which is the key parameter in the formation process of inclusions. We present recent results on the effect of Cr-doping on the transport coefficients on a wide set of single crystalline samples. Magnetic measurements were used to corroborate the conclusions drawn from the transport and X-ray measurements.