الفهرس 
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Abstract
Alizarin red S (ARS) thin films has been prepared by the conventional thermal evaporation technique. The structural, optical, electrical and photovoltaic properties of the films have been investigated. The structural properties of the films have been studied by using the differential scanning calorimeter (DSC), X-ray diffraction (XRD) and Fourier transforms infrared spectroscopy (FTIR) techniques. The spectra of the transmittance and reflectance determined at the normal incidence of light for ARS thin films showed that as-deposited ARS thin films are good absorber for light waves in the spectral range of (200-1000 nm) and they are optically transparent in the spectral range of (1000-2500 nm).
The dispersion analysis has been carried out on the as-deposited and annealing thin films to obtain the dispersion parameters such as dispersion energy, oscillator energy, the high frequency dielectric constant and the lattice dielectric constant of the ARS thin films. The absorption analysis has been performed to determine the type of electronic transitions and to evaluate the optical band gap of the films. Both of direct and indirect transitions are found to be probable for ARS thin films in both as-deposited, and annealed thin films. The study of non-linear optical properties such as susceptibility, refractive index and absorption coefficient have been carried out for as deposited and annealed thin films.
The direct current electrical conductivity of ARS thin films with two gold electrodes in planar configuration is measured as a function of temperature. The temperature dependence of the conductivity showed a semiconductor behavior. Furthermore, the dielectric properties and alternating current conductivity, of ARS thin film in the frequency range 100 Hz - 5 MHz through the temperature range 303 - 393 K were investigated. The activation energy, ΔEac, was found to decrease as the frequency increases. The dark current-voltage (I-V) characteristics of Au/ARS/n-Si/Al hetero-junction solar cell measured at different temperatures ranging from (303-333 K) have been investigated.