SnS films have been deposited at room temperature by the chemical bath deposition technique. The films have been examined to evaluate their structure, morphology, composition and optical properties. SnS films were polycrystalline with an orthorhombic-herzenbergite structure. The lattice parameters and crystallite size of the sample have been calculated to be a = 4.39 Å, b = 11.17 Å, c = 3.97 Å with a/c = 1.106, and 67 nm, respectively. SnS films have been well crystallized in the form of cylindrical rods and the atomic ratio of Sn to S is 49.8 : 50.2. The optical properties of the sample have been studied using the transmittance and reflectance measurements as a function of wavelength between 190 and 3300 nm. The optical band gap is direct with a value of 1.31 eV. The refractive index and extinction coefficient as a function of wavelength for the film were investigated from the transmittance spectrum by applying the envelope method. The optical parameters of the material such as dielectric constants (n, k, ε1 and ε∞), plasma frequency ωp and carrier concentration Nopt were also evaluated.

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Polycrystalline CdS films have been deposited by ultrasonic spray pyrolysis method. The electrical properties of the sample have been studied by means of an analysis based on the thermally stimulated current (TSC) spectrum at a heating rate of 0.06 K s−1 in the temperature range of 40–250 K. In order to evaluate the trap parameters of the sample, we have used curve fitting and initial rise methods. The TSC spectrum indicates that the sample has seven overlapped peaks located at levels in the range of 0.021–0.138 eV below the conduction band. The values of the frequency factor, the capture cross section and the concentration of the traps have been determined from the observed peaks in the TSC spectrum of the sample.

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PbS film has been produced by chemical bath deposition (CBD) method onto glass substrates using aqueous solution containing Pb(NO3)2, Na2SO3, NaOH and SC(NH2)2. The deposition was carried out at room temperature of 26°C and a stirring speed of 60 rpm for an hour. The PbS film has been characterized by x-ray diffraction, field emission scanning electron microscopy, Fourier transform infrared spectroscopy, Raman spectroscopy and optical absorption spectroscopy techniques. The PbS film is polycrystalline face centered cubic phase having randomly preferential orientation in the [101], [200], [220] and [400] directions. The texture coefficient, lattice parameter, strain, crystallite size, and dislocation density were estimated from x-ray diffraction results. Fourier transform infrared result reveals that the presence of PbS and various functional groups in PbS sample. Raman spectrum of the sample shows PbS phase and lead oxysulfates. The optical band gap of the PbS film has been studied using the optical absorbance measurement as a function of wavelength between 200 and 2750 nm. The optical direct band gap of the sample is calculated to be 1.28 eV. The optical band gap of PbS sample exhibited a blue-shift compared with that of bulk PbS.

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