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ZnO lms were deposited on glass substrates by ultrasonic spray pyrolysis technique at a substrate temperature of 300 ± 5• C. All of the lms have been annealed at 500• C temperature for dierent time (1, 2, and 3 h) to improve the optical, electrical and surface properties. The eect of annealing time on the lms of physical properties has been investigated. UV-Vis spectrophotometer has been used for transmittance measurements. Also, band gap values of the lms have been determined by optical method. Atomic force microscopy has been used to have information the surface morphology and roughness values of the lms. Thicknesses, refractive index and extinction coecient values of the lms have been determined by spectroscopic ellipsometry technique. The electrical conduction mechanisms and resistivity of the lms were investigated using two probe technique. After all the investigations it was concluded that annealing time has a dramatic eect especially on the surface, optical properties and electrical resistivity values of ZnO lms. From the results of these investigations, the application potential of the lms for solar cell devices as transparent electrode was searched.

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In this study, undoped and cobalt (Co)-doped zinc oxide (ZnO) films were successfully produced by ultrasonic spray pyrolysis (USP) technique at low temperature (350[Formula: see text]C). The optical and surface properties were investigated as a function of Co content. The optical parameters (thickness, refractive index and extinction coefficient) were determined using spectroscopic ellipsometry (SE) and it was seen that the refractive index and extinction coefficient values of Co-doped ZnO films decreased slightly depending on the increasing of Co doping. For investigation, the transmittance and photoluminescence (PL) spectra of the films, UV–Vis spectrophotometer and PL spectroscopy were used at room temperature. The transmittance spectra show that transmittance values decreased and Co[Formula: see text] ions substitute Zn[Formula: see text] ions of ZnO lattice. The optical band gap values decreased from 3.26 eV to 2.85 eV with the changing of Co content. The results of PL spectra exhibit the position of the different emission peaks unchanged but the intensity of peaks increased with increasing Co doping. Also, the surface properties of the films were obtained by atomic force microscopy (AFM) and these results indicated that the surface morphology and roughness values were prominently changed with Co doping.

Zn 1Àx Mg x O (ZMO) films were prepared by the ultrasonic spray pyrolysis technique and effects of doping on structural, optical, electrical, and surface properties were examined. The film structures were studied by X-ray diffraction. X-ray diffraction patterns of the films showed that the ZMO films exhibited hexagonal wurtzite crystal structure with a preferred orientation along (0 0 2) direction. Texture coefficient, grain size values, and lattice constants were calculated. The optical properties like transmission, reflection, and absorption were investigated with UV-Vis spectrophotometer. The optical measurements reveal a shift in absorption edge and optical band gap of ZMO films changed with Mg content. Optical parameters (refractive index, extinction coefficient) and thicknesses of the films were investigated by spectroscopic ellipsometry (SE). Surface and electrical properties of the films were studied using atomic force microscopy and four-probe technique, respectively. After all investigations, it is concluded that the ZMO thin films can be used in photovoltaic solar cells as window materials and cell efficiencies can be increased using different content rates.

The interest in NiO films has been growing fast due to their importance in many applications in science and technology. NiO films are an attractive material and are used common application area such as an antiferromagnetic layer, p-type transparent conducting film, electrochromic devices and chemical sensors. Also, NiO is a good candidate for p-type semiconductor films due to its wide band gap energy from 3.6 to 4.0 eV. In this work, NiO films have been grown on glass substrates by ultrasonic spray pyrolysis technique using NiCl 2 .6H 2 O as spraying solution. Films have been annealed at 500 °C in air during 1 h. Optical measurements of NiO film have been carried out at room temperature using a UV-VIS spectrophotometer. Band gap of as-deposited and annealed films have been calculated by using optical method and found as 3.67 eV and 3.7 eV, respectively. Thicknesses of the films have been determined by filmetrics thin film measurement system. Surface properties of the films have been investigated with an atomic force microscope and electrical resistivity measurements have been performed by a four probe set-up. Consequently, the optical, electrical and surface differences have been determined between as-deposited and annealed NiO films produced by ultrasonic spray pyrolysis.