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Ga doped ZnO thin films were formed by the Ultrasonic Chemical Spray Pyrolysis method onto substrates using zinc acetate and gallium (III) nitrate hydrate as precursors. The structural, optical, surface and electrical properties were studied as a function of increasing Ga doping concentration from 0 to 6 at %. Structural studies were shown polycrystalline with a hexagonal crystal structure. The transparency in the visible range was around 85% for thin film deposited using 6 at % Ga doping. With the aim of determining surface images and surface roughness of the films atomic force microscope images were taken. Ga doping of ZnO thin films could markedly decrease surface roughness. Electrical resistivity was determined by four point method. The resistivity 2.0% Ga doped ZnO film was the lowest resistivity of 1.7 cm. In the photoluminescence measurements of the films, existence of UV and defect emission band was observed. As a result, Ga doped ZnO films have advanced properties and promising materials for solar cells.

Ga doped ZnO thin films were formed by the Ultrasonic Chemical Spray Pyrolysis method onto substrates using zinc acetate and gallium (III) nitrate hydrate as precursors. The structural, optical, surface and electrical properties were studied as a function of increasing Ga doping concentration from 0 to 6 at %. Structural studies were shown polycrystalline with a hexagonal crystal structure. The transparency in the visible range was around 85% for thin film deposited using 6 at % Ga doping. With the aim of determining surface images and surface roughness of the films atomic force microscope images were taken. Ga doping of ZnO thin films could markedly decrease surface roughness. Electrical resistivity was determined by four point method. The resistivity 2.0% Ga doped ZnO film was the lowest resistivity of 1.7 cm. In the photoluminescence measurements of the films, existence of UV and defect emission band was observed. As a result, Ga doped ZnO films have advanced properties and promising materials for solar cells.

In this work optical, electrical, structural and surface properties of polycrystalline ZnO thin films grown from aqueous solutions (with pH = 5) have been reported. The films have been deposited on glass substrates by ultrasonic spray pyrolysis technique at a substrate temperature of 350 ± 5 °C. Zinc acetate dissolved in deionized water has been used as starting solution. The ZnO thin films have been annealed in air at 450 and 500 °C to improve their physical characteristics. X-ray diffraction reveals that the films are polycrystalline in nature having zincite type crystal structure. Electrical resistivity values of the films have been increased after annealing process. Films are highly transparent in the visible region. The dependence of refractive index, n, and extinction coefficient, k, on the wavelength for ZnO films has been also reported. Optical band gap values have been determined using optical method. Finally, it has been concluded that annealing temperature has an important effect on the optical, structural, surface and electrical properties of the deposited films.