Effect of Gamma Ray Irradiation on Structural and Optical Properties of ZnO Thin Films

Abstract

In this research, the structural and optical measurements were made on the Zinc oxide(ZnO) films prepared by two methods once by using chemical spray pyrolysis technique, andanother by using thermal evaporation technique before and after irradiation by Gamma –Ray(γ – rays) from source type (Cs 137) with an energy (0.611)MeV as a function of gamma dose(0.15,0.3 and 0.45) Gy. The thickness of all films prepared by two method was about (300 ±50) nm.XRD is used to characterize the structural properties, the results demonstrated that allsamples prepared by two method before and after irradiation have polycrystalline structurewith a preferred orientation (002).Also it showed that the structural properties are weaklydependent on the gamma dose. The optical measurement shows that all ZnO films preparedby two method have a direct energy gap, and they in general decrease with the increase ofGamma dose while the optical constant such as absorption coefficient, refractive index,extinction coefficient, real and imaginary parts of the dielectric constant and opticalconductivity showed an opposite trend, these values increase with the increase of irradiationdose. As well as all optical properties for the samples prepared by thermal evaporationtechnique is higher than the samples prepared by chemical spray pyrolysis technique