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Copper sulfide (CuS) thin films were prepared on commercial glass substrates by Chemical Bath Deposition (CBD) method using solution of different copper salts at 50 °C temperature for seven hours. Different anions of copper salts that is crucial for the properties of the films affect the precipitation mechanism and growth rate. For this reason, the effect of the different copper salts on the properties of CuS thin films was investigated and discussed. The influence of the different copper salts in the chemical bath was determined by means of optical transmission of the thin films in the wavelength range of 400–1100 nm taken at room temperature. Next, using these data, the optical band gap values E g , the extinction coefficient k, the refractive index n , and the real ε 1 and imaginary parts ε 2 of the dielectric constant were calculated. The crystallographic structure of CuS thin films were analyzed with an X-ray diffractometer (XRD). XRD analysis was revealed the polycrystalline and hexagonal phase of CuS thin films. The surface roughness of the films were measured by AFM. The surface roughness of the thin films was different despite the same deposition time. [ABSTRACT FROM AUTHOR]

γ -MnS thin film was deposited at 40 °C temperature on glass substrate by Chemical Bath Deposition (CBD) method that has superior advantageous in terms of fast and cheap production. MnS thin film was annealed in nitrogen atmosphere at temperatures 100, 200, 300, 400, 500 °C for an hour. The effect of annealing temperature on structural and optical properties have been investigated. X-ray diffraction (XRD) analysis revealed that gamma-MnS thin film had the phase change and oxidized at 400, 500 °C annealing temperature. The grain size of the annealed film was calculated between 241 and 280 Å as a function of annealing temperature. It was observed that optical transmission values decreased at wavelength of 400–700 nm (visible region) after annealing at temperatures 400 and 500 °C. Increasing annealing temperature induces reduction in energy band gap values from 3.89 eV down to 3.46 eV. Refractive index ( n ) values were calculated by envelope method. Refractive index values at visible region increased from 2.03 to 2.54 with increasing annealing temperature. [ABSTRACT FROM AUTHOR]

In this work, tin dioxide (SnO 2) thin films were prepared at various substrate temperatures (380–440 °C, in steps of 20 °C) on glass substrates by the Spray Pyrolysis Method. X-ray Diffraction (XRD) measurements revealed that the SnO 2 thin films were formed in a tetragonal crystallized structure. The electronic structure of the tin dioxide thin films that were prepared at several substrate temperatures were investigated with the collected X-ray Absorption Spectroscopy (XAS) data. The crystal structure analysis was also supported by the Extended X-ray Absorption Fine Structure (EXAFS) data analysis extracted from the X-ray Absorption Fine Structure (XAFS) data. Unstable crystal behaviors were detected in the samples due to metastable SnO structure formations as a result of phase transitions from the SnO to SnO 2 structure during the annealing processes. Clear information on the atomic displacements in the samples as a picture of the crystal mechanism was obtained from the analysis of EXAFS data. The SnO 2 thin films were found to exhibit high transmittance (average 90%) in the 400–1100 nm interval. The thickness of the SnO 2 thin film (t) and refractive index (n) were calculated from transmittance spectra in the visible region using envelope method. The direct energy band gaps of the films obtained were 4.01–4.09 eV. Atomic force microscope (AFM) measurements were performed in order to investigate the surface roughness of the SnO 2 thin films. [ABSTRACT FROM AUTHOR]

We have investigated the thickness effect of Cu 2 O thin films on the electronic structure deposited by the successive ionic layer adsorption and reaction (SILAR) method. Crystal, optical and electronic properties of the Cu 2 O thin films were studied by X-ray diffraction (XRD) and X-ray absorption near edge spectroscopy (XANES). According to the crystal structure analysis, films were determined to be mainly in cubic Cu 2 O structures. The XANES study have shown that Cu L 2,3 absorption edges are influenced by the chemical state of the Cu atoms strongly and a sole ionic picture is not enough to describe the L-edge spectra of Cu 2 O. It has been observed that Cu L 2,3 -edge spectra of the samples present typical electronic features of both monovalent Cu (I) and Cu (II) divalent states. The grains have an average size of 2.5 nm and XRD measurements revealed that ( 111 ) plane is the preferential orientation. Optical studies have shown that the optical absorption edge shifted to higher energies as the film thickness increases. It was found that the optical band gap was significantly influenced by the film thickness. Our results exhibited that the increment of the optical band gap of Cu 2 O thin films associated with a significant decrease of Cu-Cu interaction as a result of the increase in the film thickness. [ABSTRACT FROM AUTHOR]

CuS thin films with various molar concentrations at 70 °C temperature were deposited by Chemical Bath Deposition. The effect of molar concentration on the structural, linear optic, nonlinear optic and morphological properties of CuS films were deeply investigated. X-ray diffraction (XRD) analysis exhibited that CuS films were formed in polycrystal structure and hexagonal phase. The fundamental optical parameters of films such as energy band gap, reflection and extinction coefficient were determined with the results of optical transmission and optical absorption by UV–vis spectrophotometer. The energy band gap values were reduced with increasing films thickness. Moreover, the dependence of the optical dielectric constants, loss tangent, optical conductivity, surface and volume energy loss function values on the molar concentrations were studied. Furthermore, the third order nonlinear optical susceptibility and nonlinear refractive index, which is considered to be the base of the first order optical susceptibility with nonlinear optical properties were discussed in detail. • Copper sulfide (CuS, covellite) thin films were prepared at various molar concentrations (0.1 M, 0.3 M, 0.5 M) at a temperature of 70 °C by Chemical Bath Deposition. • The energy band gap reduced with increasing the thickness of CuS thin films. • The refractive indices of the films obtained at 0.1 M, 0.3 M and 0.5 M at 550 nm were calculated as 2.31, 2.63 and 2.64, respectively. • It was determined that the first-order optical susceptibility values of CuS films varied in the range of 0.268–3.031 in the visible region. • The third-order nonlinear optical susceptibility values varied in the range of 8.75 × 10−10–1.44 × 10−5 esu. [ABSTRACT FROM AUTHOR]

Gamma-MnS thin films were deposited on glass and indium tin oxide (ITO) substrates at 40 °C temperature by Chemical Bath Deposition (CBD) method. XRD measurements revealed that the gamma-MnS films are polycrystalline in the wurtzite phases and show a preferential orientation along the c -axis. The grain size of the films that were deposited onto the glass and ITO were calculated as 327 nm and 189 nm, respectively. The energy band gap of the films deposited onto glass and ITO were also calculated as 3.56 eV, 3.74 eV, respectively. The refractive index of the gamma-MnS at the visible region (400–700 nm) were measured as 2.1 and 1.63 for the glass and ITO substrates, respectively. Hall measurement revealed that the gamma-MnS films showed n -type conductivity and the resistivity of the gamma-MnS films deposited on the glass and ITO substrates were measured as 7.1 × 105 Ωcm, 3.04 × 102 Ωcm, respectively. • Gamma-MnS thin film were prepared on glass and indium tin oxide substrates at 40 oC by chemical bath deposition method. • The grain size of the films that were deposited on glass and ITO were calculated as 327 nm, 189 nm, respectively. • The energy band gap of films deposited on glass and ITO substrates was calculated as 3.56 eV, 3.74 eV, respectively. • The refractive index of MnS at the visible region were measured as 2.1, 1.63 for glass and ITO substrates, respectively. • The electrical resistivity of MnS film deposited on glass and ITO were measured as 7.1 × 105 Ωcm, 3.04 × 102 Ωcm, respectively. [ABSTRACT FROM AUTHOR]