الفهرس 
Introduction and aim of the workOnly 14 pages are availabe for public view
 |  | from | 180 |  |  |
| | | from | 180 | | |
Abstract
Thin films of (As2Se3)1-xAgx (X = 0.0,1.0,2.5 and 5.0 at. %) were prepared by thermal evaporation of the bulk quenched materials. Structural investigations have been carried out by both x-ray diffraction and differential scanning calorimerty (DSC). Results reveal the amorphous nature of the samples withy a crystalline – like structure formed at 1 at.% silver content. The transmission spectra of the samples were obtained using a double beam spectrometer in the wavelength range 500 to 1000 nm at room temperature. The Swanepoel method based on the use of the maxima and minima in the interference fringes has been successfully developed and applied. The technique used took into consideration both the uniform and non-uniform nature in the film thickness. Using the exact calculation of the film thickness and the real refractive index, the extinction coefficient, absorption coefficient, the optical bandgap and the oscillator and dispersion energies were obtained as a function of silver contents. Electrical investigation including current-temperature (I-1/T) dependence, isothermal current (IC) decay and thermal stimulated charge release current (TSCRC) have been carried out as a function of silver metallic concentrations. Results confirm the presence of some different local trap levels within the bandgap, which affect the transport phenomena without changing the electronic structure of the samples. On the other hand, data reveals the formation of some crystalline-like structural units at low metallice Ag (1 at.%) and silver cluster, occupying the interlayer position in the network of the glass matrix, at higher silver contents.