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The spray pyrolysis was used for the deposition of CuZnSn(S, Se) (CZTSSe) kesterite thin films. The basic spray pyrolysis solution was prepared from two precursor solutions containing thiourea and cooled to a temperature near 1°C, which leads to minimizing the number of insoluble hydrates of copper chloride. The optimal substrate temperature was 350°C and the distance from the sprayer nozzle 30 cm. The as-deposited CuZnSnS layers were annealed in S atmosphere for the compensation of the sulfur deficiency and with the addition of Sn in order to avoid tin loss. CuZnSn(S, Se) thin films were obtained after the annealing of as-deposited films in the (S + Se) atmosphere. The surface morphology and composition of obtained thin films were investigated using the energy dispersive X-ray (EDX) microanalysis and Raman spectroscopy measurements. The structural characterization by the grazing incidence X-ray diffraction (GIXRD) showed the presence of CuS phases in all of the annealed thin films. For the Se/(S + Se) ratio of the thin films annealed in the (S + Se) atmosphere was established from EDX measurements and analysis of GIXRD data, the results are in satisfactory agreement. [ABSTRACT FROM AUTHOR]

Structures ITO/SiO/ n-Si are fabricated by pulverization of solutions of indium and tin chlorides on the (100) surface of silicon wafers with resistivity 4.5 Ω cm. The influence of the state of the Si surface on the efficiency of structures as photoelectric converters is investigated. It is shown that structures with an unetched surface of silicon wafers are the most efficient. Solar cells based on studied ITO/SiO/ n-Si structures with an inverse layer demonstrate an efficiency close to 16% in AM 1.5 conditions. [ABSTRACT FROM AUTHOR]

Thin films of predominantly amorphous n-type SiC were prepared by non-reactive magnetron sputtering in an Ar atmosphere. A previously synthesized SiC was used as a solid-state target. Deposition was carried out on a cold substrate of p-type Si (100) with a resistivity of 2 Ωcm. The Raman spectrum shows a dominant band at 982 cm−1, i.e., in the spectral region characteristic for SiC. It was found that the root mean square roughness varies from about 0.3 nm to 9.0 nm when the film thickness changes from about 2 nm to 56 nm, respectively. Transmission electron microscopy studies showed that SiC thin films consist predominantly of an amorphous phase with inclusions of very fine nanocrystallites. A heterostructure consisting of a p-type Si (100) and a layer of predominantly amorphous n-type SiC was fabricated and studied. The investigation of its electrical and photoelectric properties shows that the entire space charge region is located in Si. This is in addition confirmed by the spectral dependence of the p-Si/n-SiC photosensitivity. The barrier height at the p-Si/n-SiC interface estimated from dark I- V characteristics is of the order of 0.9-1.0 eV. Load I- V characteristics of p-Si/n-SiC-nanolayer solar cells demonstrate under standard AM1.5 illumination conditions a conversion efficiency of 7.22%. [ABSTRACT FROM AUTHOR]

Luminescence spectra of naphthalene and benzophenone doped with their monosubstituted derivatives at 4.2 K were studied. The multiplet structure of these spectra was analyzed using the symmetry properties of the free molecules and crystal structures. It was shown that fl uorescence and phosphorescence spectra of the studied objects had a doublet character. [ABSTRACT FROM AUTHOR]

The results on the optimization of the parameters of solar cells (SCs) with monofacial and bifacial sensitivity based on nITO-SiO- n- nSi structures with isotype junctions are described. The developed technique of the structurization of silicon wafer surfaces makes it possible to increase the efficiency of solar radiation conversion to electric energy by up to 15.8% for monofacial SCs and up to 20.9% for bifacial SCs. [ABSTRACT FROM AUTHOR]

The possibility of nanostructuring of surfaces of indium phosphide with hole conduction is confirmed. The technique of manufacturing and research of SnO2/InP heterostructures with a nanoporous surface at the interface is developed. It is shown that the investigated structure can form a basis for working out photovoltaic devices with an enlarged active surface. [ABSTRACT FROM AUTHOR]

Peculiarities of obtaining of tin oxide and titanium oxide layers and semiconductor structures on their basis are described. The X-ray diffraction data show that the SnO2 and TiO2 layers possess the tetragonal crystal structure (anatase modification for TiO2). The results of analysis of the elemental composition and impedance investigations of the fabricated structures in model chloride-sulfate solutions demonstrate that the oxide/SiO2/Si structures are obtained if Si substrates are used. In the case of InP substrates, the oxide layer at the interface is not detected and the corresponding structure is oxide/InP. The results of investigations of corrosion show that a substantial shift of the corrosion potential to the anode region is observed in the case of deposition of SnO2 and TiO2 oxide layers on Si and InP crystals and fabrication of corresponding semiconductor structures. This demonstrates the possibility of the use of these materials in photoelectrochemical applications. [ABSTRACT FROM AUTHOR]

The photoelectric properties of ITO/n-Si solar cells with ITO-side oblique incidence of linearly polarized light on the solar cells have been studied. Polarization photosensitivity and an increase in the relative quantum efficiency of photoconversion as a result of a decrease in reflection losses were found. The induced photopleochroism coefficient P[sub I] increases with the angle of incidence θ as P[sub I] ∼ θ². The polarization photosensitivity of solar cells was studied as a function of the photon energy between the band gaps of the two contiguous materials. The results show that the solar cells studied can be used as selective polarimetric photosensors. [ABSTRACT FROM AUTHOR]

An ITO-n-CdTe electroluminescence structure of the semiconductor-insulatorsemiconductor type has been studied. Under forward bias hole injection from the ITO into the n-CdTe base material causes electroluminescence with its wavelength at the maximum (0.87 μm) of the spectral distribution of the luminescence. The injection coefficient and the transparency of the insulator layer are determined for both types of carriers. [ABSTRACT FROM AUTHOR]

Indium phosphide heterostructures and transparent conducting films of wide-gap oxides have previously been used in the development of highly efficient solar cells, making it possible to bring their efficiencies up to 18% [M. M. Koltun, Optics and Metrology of Solar Cells [in Russian], Nauka, Moscow (1985); V. M. Botnaryuk, L. S. Gagara, L. V. Gorchak et al., Geliotekhnika 23, 37 (1990); V. Botnariuc, L. Gagara, E. Negru et al., Solar Energy in Romania 2(1), 53 (1993)]. In the present paper results are reported from the first studies of the photoelectric properties, in linearly polarized light, of solar cells consisting of a heterojunction between single crystal indium phosphide and a mixed indium and tin oxide film (ITO film, E[sub g] ≅ 3.6 eV [G. Check and A. Genis, Solid State Techol. 23(1), 102 (1980)]). [ABSTRACT FROM AUTHOR]