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Abstract: Different sequentially stacked binary chalcogenide layers (CuSe, ZnSe, and SnSe) deposited by vacuum evaporation onto molybdenum covered soda-lime glass substrates were used as precursors to form Cu2ZnSnSe4 films. The influence of the stacked binary layer sequence, substrate temperature, both the duration and speed of deposition and the post deposition treatment atmosphere on the structural and the morphological parameters of the Cu2ZnSnSe4 thin films was studied. Our results indicate the possibility of replacing the Se2 selenisation with a thermal treatment in an SnSe2 atmosphere to avoid the selenisation of the Mo substrate and MoSe2 formation. This SnSe2 treatment forms p-type Cu2ZnSnSe4 films with an optical band-gap of 1.14eV and a solar cell structure with an efficiency of up to 3%. [Copyright &y& Elsevier]

Abstract: Hybrid solar cells on the basis of CuInS2 (CIS) photoabsorber on Cu-tape (CISCuT) in combination with organic buffer layers of Zn-phthalocyanine (ZnPc), ZnPc:fullerene (ZnPc:C60) composite and conductive polymer buffer layers of poly(3,4-ethylenedioxythiophene) (PEDOT) doped with polystyrenesulfonate (PSS) were prepared using vacuum evaporation and spin-casting techniques. To prepare solar cells with an active area of 2 cm2, the appropriate deposition parameters and thickness of ZnPc, ZnPc:C60 and PEDOT-PSS layers were selected experimentally. For preparation of semitransparent contact-window layers, chromium and gold were evaporated on the surface of ZnPc, ZnPc:C60 and PEDOT-PSS films. It was found that an intermediate chromium layer improves PV properties of the structures with organic buffer layers. The photosensitivity at small illumination intensities of complete structures with ZnPc and ZnPc:C60 layers increased more than one order of magnitude in comparison with the structures where the PEDOT-PSS buffer layer was deposited. The presence of C60 in the composite-buffer layer results in increased photoconductivity. The best structure with composite ZnPc:C60 buffer layer showed an open-circuit voltage of 560 mV, a short-circuit current density of around 10 mA/cm2 and a photoconversion efficiency of around 3.3% under the light illumination with an intensity of 100 mW/cm2 from a tungsten–halogen lamp. The low transmission of the semitransparent chromium–gold window layer is the reason for relatively low current density. [Copyright &y& Elsevier]

Abstract: The mechanism of the underpotential electrodeposition of copper indium diselenide (CIS) in the presence of an excess of In3+ was studied. It was found that the value of indium and copper ratio (In/Cu) in the films electrodeposited in the potentials area from −0.2 to −0.6 V (vs. SCE) is independent of the concentration ratio of Cu2+/In3+. At the same time, the concentration of indium in the films obtained is determined both by the deposition potential and the ratio of Se(IV)/Cu2+ in the solution. The proposed model provides the list of the formed compounds as a function of the solution concentration and the applied potential. [Copyright &y& Elsevier]

Abstract: CuInSe2 (CIS) films have been prepared by one-step electrodeposition technique. The effect of thermal treatment in vacuum and under selenium vapour pressure on the composition and structure of CIS electrodeposited layers has been investigated. The structure and composition of these samples have been investigated by SEM, XRD, EDX and Raman spectroscopy. It was found that recrystallization of CIS thin film occurs with segregation of Cu–Se phases onto the bottom of films and formation of CIS grains different by size and composition. [Copyright &y& Elsevier]

Abstract: Cu–In–Ga (CIG) layers of graded composition have been grown by one-step electrodeposition from thiocyanate complex electrolytes. The Ga-content is adjusted from two to 30 at.% by changing stirring rate, deposition time and solution composition. The as prepared CIG precursors are selenizated at 500 °C in a two-temperature zone furnace at different Se-vapour pressures. The influence of the Se-vapour pressure on morphology and photoluminescence properties of Cu(In, Ga)Se2 films are discussed. [Copyright &y& Elsevier]

Abstract: The Cu–In–Ga layers with various Ga-content were produced from one bath by electrodeposition on molybdenum substrates. The use of complex thiocyanate electrolyte allows for a remarkable shift of the deposition potential of elemental copper to the deposition potentials of indium and gallium. The influence of different deposition conditions on film properties was investigated and the possibility of reproducible Cu–In–Ga precursor layer deposition with good composition control was demonstrated. The Cu–In–Ga precursors were selenized in a quartz tube furnace at 560 °C under the selenium pressure of 10 mbar. Cross-sectional energy dispersive X-ray analysis (EDX) line scan measurements showed an accumulation of Ga towards the Mo back contact. The best solar cell structures on the base of selenized Cu(In,Ga)Se2 (CIGS) thin film gave the photoconversion efficiency of 4%. [Copyright &y& Elsevier]