Silver nanoparticles have potential applications in fields of nanosicence and technology. In this work, polycrystalline silver (Ag) thin films were deposited on quartz substrates by DC magnetron sputtering method at the same deposition conditions and then, the Ag films were annealed in oxygen atmosphere for 65 min at different annealing temperatures namely 300, 400, 500 and 600• C. The crystal structure of the films was evaluated by X-ray diffraction. The atomic force microscopy and scanning electron microscopy were employed for surface morphological studies of the films. Normal-incidence transmittance over the wavelength range of 200-2500 nm was measured using a spectrophotometer. The results show that the crystallization of the films increases after annealing and that the Ag films without annealing have lowest roughness. Annealing temperature effectively influences the surface morphology of the films. Optical studies reveal that the as-deposited Ag film has metallic behavior with zero transmittance and after annealing, the transmittance increases due to the formation of silver oxide phases in the films.

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The structural and optical properties of aluminum nitride (AlN) films deposited on glass and silicon substrates by single ion beam sputtering technique have been investigated. The X-ray diffraction and Fourier transform infrared spectroscopy (FTIR) study revealed the formation of the amorphous phase of AlN. The optical characteristics of films, such as refractive index, extinction coefficient, and average thickness, were calculated by Swanepoel's method using transmittance measurements. The refractive index and average roughness values of the films increased with film thickness. Moreover, it was found that thickness augmentation leads to a decrease in optical band gap energy calculated using Tauc's relation.

Nanocrystalline a-MoO 3 thin films were prepared successfully by thermal annealing of molybdenum (Mo) thin films deposited on quartz and silicon substrates using DC magnetron sputtering method. The influence of annealing temperatures ranging from 400 to 1,000°C on the structural, morphological and optical properties of the prepared films was investigated by X-ray diffraction, Fourier transform infrared spectrophotometer (FTIR) atomic force microscopic and UV-vis spectroscopy, respectively. The results show that the crystallinity and surface morphology of the films are strongly dependent on the annealing temperature. Also, the optimum annealing temperature of Mo films in our experiment was 600°C and the films formed at this temperature exhibit only the (0k0) reflections and indicated the layered structure of a-MoO 3 . The FTIR spectra confirm the formation of MoO 3 . The transmittance of the MoO 3 films on quartz substrate was improved with increasing annealing temperature.

Silver (Ag) nanolayers were deposited on nickel oxide (NiO) thin films by DC magnetron sputtering. The thickness of Ag layers was in range of 20-80 nm by variation of deposition time between 10 and 40 s. X-ray diffraction results showed that the crystalline properties of the Ag/NiO films improved by increasing the Ag film thickness. Also, atomic force microscopy and field emission scanning electron microscopy images demonstrated that the surface morphology of the films was highly affected by film thickness. The film thickness and the size of particles change by elevating the Ag deposition times. The composition of films was determined by Rutherford back scattering spectroscopy. The transmission of light was gradually reduced by augmentation of Ag films thickness. Furthermore; the optical band gap of the films was also calculated from the transmittance spectra.