Structural, optical and electrical properties of F doped ZnO films: Experimental and theoretical study

Abstract

In this paper, we theoretically and experimentally investigated the structural, optical and electronic properties of Fluorine-doped zinc oxide (FZO) with different concentrations of the doping element. The undoped and F doped ZnO thin films have been elaborated on glass substrate by spray pyrolysis technique. X-ray diffraction (XRD) and photoluminescence measurement are used to characterize the structural and optical properties of ZnFxO1-x films with x = 0.0, 0.02, 0.05, 0.07. The results showed that all the elaborate thin films crystallize in the hexagonal structure of the wurtzite type with a preferential orientation of the crystallites along the direction (002) along the c axis perpendicular to the surface of the substrate. All FZO thin films had relatively higher average transmittances, approximately 80–90%, in the visible region as compared to the undoped ZnO thin films. The electronic band structure, total and partial density of states of FZO were investigated studied by Density Functional Theory to examine the change in the band gap of ZnO with F doping. The results of this study indicate that with the increase of the fluorine concentration in the ZnO matrix, the band gap energy decreases which is in good agreement with the experimental results.