Najoua Kamoun-Turki

Physical properties of Cu2ZnSnS4 thin films deposited by spray pyrolysis technique

Thin films of Cu2ZnSnS4 (CZTS) were deposited on Pyrex substrates at various temperatures by spray pyrolysis technique from aqueous solution containing an economic stannous chloride (SnCl2) precursor for the tin and the effect of substrate temperature on the structural and opto-electronic properties was investigated. X-ray diffraction patterns and Raman spectroscopy reveal that all the CZTS films exhibited kesterite structure with preferential orientation along the (1 1 2) direction and some secondary phases. Also, they possessed different band gaps, which were found to lie between 1.52 and 1.81 eV, indicating that CZTS compound has absorbing properties favorable for applications in solar cell devices. Van der Pauw technique and Hall effect measurements were used to determine the electrical properties of CZTS films and the resistivity was of about 0.12 Ω cm for film grown at 280 °C.

Effect of indium doping on physical properties of nanocrystallized SnS zinc blend thin films grown by chemical bath deposition

SnS:In thin films have been successfully prepared on Pyrex substrates using low cost chemical bath deposition technique with different indium concentrations (y=[In][Sn]=4%,6%,8%,and10%). The structure, the surface morphology, and the optical properties of the SnS:In films were studied by x-ray diffraction, scanning electron microscope, atomic force microscopy, and spectrophotometer measurements. In order to obtain a thickness of the order of 308 ± 10 nm for potential applications in solar cell devices, a multilayer deposition has been prepared. It is found that the physical properties of tin sulphide are affected by indium concentration. In fact, x-ray diffraction study showed that better crystallinity in zinc blend structure with preferential orientations (111)ZB and (200)ZB was obtained for y equal to 6%. According to the AFM analysis, we remark that low average surface roughness value of SnS(ZB) thin film is obtained with In concentrations equal to y = 6%. Energy dispersive spectroscopy showed the exis...

Structural, optical, and electrical properties of In2S3:Sn thin films grown by chemical bath deposition on Pyrex

Sn-doped In2S3 thin films are deposited on Pyrex. Tin is incorporated in the solution using SnCl2·2H2O. The properties of the films are investigated by X-ray diffraction (XRD), atomic force microscopy, scanning electron microscopy, spectrophotometry, and thermally stimulated current (TSC) measurements. XRD analysis reveals that the films become almost amorphous when tin exceeds well determined optimum quantity. The investigation of optical properties shows that the band gap depends on the value of the Sn concentration. It is also observed that upon adding the optimum quantity of tin, the maximum of the TSC intensity increased by 2 orders of magnitude. These results are discussed with respect to introduce the effect of tin incorporated in the physical properties.

Synthesis and characterization of Fe-doped SnS thin films by chemical bath deposition technique for solar cells applications

Undoped zinc blend tin sulphide can be used as an absorber material in thin film solar cells. In the present study, SnS thin film has been doped with iron (Fe) at different concentrations (y = [Fe]/[Sn] = 4%, 6%, 8%, 10%). Structural, morphological, chemical, optical, and electrical properties were studied by X-Ray diffraction, scanning electron microscopy associated with energy dispersive spectroscopy, atomic force microscopy, and thermally stimulated current. X-ray diffraction study shows that better crystallinity is obtained for y = 8%. Scanning electron microscopy reveals that the surface morphology of the films strongly depends on the doping concentration. The energy dispersive spectroscopy shows the presence of Fe. The band gap energy is found to be about 1.6 eV. The thermally stimulated current is dominated by the trapping centers. It increases for y = 4% compared to the undoped SnS thin film. The activation energy of trapping centers in undoped and doped SnS thin layers is also calculated.