In this work, the optical properties of Cu2S with different thickness(1400, 2400, 4400) Ǻ have been prepared by chemical spray pyrolysis method onto clean glass substrate heated at 283 oC ±2. The effectof thickness on the optical properties of Cu2S has been studied. Itwas found that the optical properties of the electronic transitions onfundamental absorption edge were direct allowed and the value of theoptical energy gap of Cu2S (Eg) for direct transition decreased from(2.4-2.1) eV with increasing of the thickness from (1400 - 4400)Ǻrespectively. Also it was found that the absorption coefficient isincreased with increasing of thicknesses. The optical constants suchas extinction coefficient, refractive index and the imaginary part ofthe dielectric constant have similar termed of variation for theabsorption coefficient.

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In this study, Cadmium Sulphide (CdS) thin films are deposited on glass substrates by means of Spray Pyrolysis method to examine the influence of electromagnetic and optical features of these films by diode laser . Accordingly, samples are feasibly irradiated by laser pointer with a power of 500 mw and a wavelength of 532 nm at distance of 10 cm from the source during dissimilar exposure times of 10, 20, 30, 40, 50, 60, 70 and 80 minutes. The absorbance spectrums have been measured by UV-visible spectrophotometer under range of 190-1100 nm. Optical parameters such as transmission, reflection, absorption coefficient (α), extinction coefficient (K), optical band gap (Eg), refractive index (n), and complex dielectric constants were evaluated from absorbance spectra. The results shows that the laser pointer irradiation cause decreased in transmittance (T), reflectance (R), absorption coefficient α, the extinction coefficient (K), refractive index (n) and the real and imaginary parts of dielectric constant and decrease in the value of the energy gap (Eg). In study of FTIR-spectrum of CdS films in different ratio of irradiation times, there was no change in the peak positions just bigger or smaller with increase in times of irradiation.

CdS and CdS:Sn thin films were successfully deposited on glasssubstrates by spray pyrolysis method. The films were grown atsubstrate temperatures 300 C°. The effects of Sn concentration on thestructural and optical properties were studied.The XRD profiles showed that the films are polycrystalline withhexagonal structure grown preferentially along the (002) axis. Theoptical studies exhibit direct allowed transition. Energy band gapvary from 3.2 to 2.7 eV.

Thin films of (Cu2S)100-x( SnS2 )x at X=[ 30,40, &50)]% with thickness (0.9±0.03)µm , had been prepared by chemical spray pyrolysis method on glass substrates at 573 K. These films were then annealed under low pressure of(10-2) mbar ,373)423&473)K for one hour . This research includes , studying the the optical properties of (Cu2S)100-x-(SnS2)x at X=[ 30,40, &50)]% .Moreover studying the effect of annealing on their optical properties , in order to fabricate films with high stability and transmittance that can be used in solar cells. The transmittance and absorbance spectra had been recorded in the wavelength range (310 - 1100) nm in order to study the optical properties . It was found that these films had direct optical band gap which decreases with the increasing SnS2 ratio , while it increasing with the increase in the annealing temperature at all ratio