Study of thickness effect on some structural and optical properties of (CdO) thin films prepared by vacuum thermal evaporation method.

Abstract

Three different thickness ( 200 ٫ 300 ٫400 ) ±20 nm thin films of ( CdO ) were prepared by vacuum thermal evaporation by depositing pure cadmium on a glass substrates at a temperature ( 300 ) K with a deposition rate ( 3.2 ± 0.1 ) nm/sec. The prepared films were oxidized at a temperature of (623) K for two hours in air. The structural properties study for the films were carried out using ( XRD ) . It is found that all the prepared films were polycrystalline and have a cubic type with preferred orientation along [111] plane. Transmittance spectrum was recorded as a function of wavelength ranging from (300 – 1100) nm for the films in order to calculate the value of the optical energy gap, kind of transitions ,optical constants as a function of photon energy, absorption coefficient , refractive index were included .