THE EFFECT OF ANNEALING ON SOME OPTICAL PROPERTIES OF PURE AND DOPED CADMIUM OXIDE

Abstract

In this reaserch the optical properties of pure and doped cadmium oxide thin films prepared by chemical spray pyrolysis method have been studied. The spectra of absorptance and transmittance for the prepared films in the range ( 330 – 900 nm) were measured, the thickness of prepared film was (6240 Å). It was found that, the value of absorption coefficient increases at (1.38-2.5) eV while decreased when the energy increased to (3.85 eV). It was found also that the energy gap value for prepared films for the allowed direct transitions, was (2.25 eV) while for doped films was 2.185 eV. The effect of annealing at (773 K) for one hour on the optical properties of the prepared films also have been done, it was found that the energy gap of pure films after annealing was (2.31 eV) and for the doped films by Cl was (2.20 eV).