الفهرس 
Theoretical Considerations and Literature SurveyOnly 14 pages are availabe for public view
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Abstract
AB thin films of different thickness have been prepared by conventional thermal evaporation technique, using a high vacuum coating unit. Optical flat glass or fused quartz substrates of rectangular shape were used. The AB films were evaporated using quartz crucible that was heated by induction from a molybdenum boat in vacuum of 10-4 Pa.
Uniform thin films of Azure B (AB) have been successfully prepared by the thermal evaporation technique. Fourier transform infrared (FTIR) measurements proved no change in chemical bonds of AB films upon annealing. XRD pattern showed that the powder of Azure B has polycrystalline structure with a triclinic crystal system. Thermally evaporated thin films of Azure B have amorphous structure which is retained in films being subjected to different annealing temperatures. It was concluded that AB films have chemical and thermal stability.
Thermal annealing increases absorption coefficient. The type of electron transition is indirect allowed transition in pristine and annealed films. The dispersion parameters such as Eo, Ed , dielectric constants ε∞, ԑL and plasma frequency ωp have been determined by applying single oscillator model.
Results show that all of these parameters are influenced by the annealing temperatures. Values of ԑL are found to be greater than ε∞ due to free carrier absorption and defects present in energy gap. The spectral behavior of the dielectric constant, ε2, depends on the energy of the incident photon, hυ,. The type of polarization process taking place in this material is determined from the spectral behavior of ε2. The spectral behavior shows four types of polarization in Azure B thin films.
The DC electrical measurements showed that AB films have a semiconductor behavior up to 403 K. the calculation of activation energy in the extrinsic conduction temperature region , 353-408K, is 0.022 eV and in the following temperature region, 413 – 458K is 0.19 eV.
AC conductivity of AB in thin film form showed frequency dependence of the AC conductivity at different temperatures. The carrier transport mechanism is correlated barrier hopping.