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The In 2 S 3 thin film is prepared using sulfurate method under a vacuum in a sealed tube of amorphous indium thin film. The later film is pre-deposited on glass with thermal evaporation. We have studied the effect of the temperature and the annealing time on the structural and morphological properties In 2 S 3 thin films. The X-ray diffraction (XRD) shows a good crystallinity found until the annealing temperature reach 280°C for an annealing duration of 30 mn. The scanning electron microscopy (SEM) for the thin films of In 2 S 3 layer, synthesized at different temperature for the annealing time at 15mn, revealed more homogenous layer until 320°C. Optical analyses by absorption spectroscopy show that the energy band gap is a function of the annealing condition. This band gap decreases from 3 eV to 2.6 eV when the annealing temperature is varied from 200°C to 400°C. The obtained In 2 S 3 thin films have a transmittance higher than 65%.

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Tin-doped indium oxide (ITO) films have been prepared by a screen printing (SP) method. The obtained SPITO films are granular and porous. Sheet resistance of as-made layers, measured by the four-probe method, varies from 5 to 10 IdL depending on firing time. The electrical behaviour of ITO films under different storage conditions was studied. We show qualitatively that the sheet resistance of ITO films depends on oxygen and water vapour pressures. The effect d heat treatment on sheet resistance in air and vacuum was also studied. The interpretation of the observed behaviours is based on the adsorption-desorption and diffusion phenomena. The refractive index n of the films has been determined from experimental R(A) spectra. The dielectric constant &-of the films is deduced from an n2 = fo?) plot by using Drude theory. The degree of porosity of the films and the refractive index of the ITO crystallites were evaluated.by simulating SP ITO as an effective medium. Carrier concentration and mobility were estimated from optical parameters by taking the electron reduced mass m' = O.3me. Finally, the first allowed direct transitions between the valence band and the conduction band, estimated from an a2(hv) plot, were found to be in the range 44.12 eV, depending on fabrication parameters