Influence of Fe Doping on the Optical and Magnetic Characteristics of RTA Treated Transparent Zn1-xFexO Nanocrystalline Films

Abstract

Herein transparent Zn1-xFexO nanocrystalline films have been prepared on glass substrates by sol-gel method followed by rapid thermal annealing treatment. The effecs of Fe doping on the microstructure, transmittance and magnetism of Zn1-xFexO nanocrystalline films are investigated. The x-ray diffraction patterns of all compositions show the same wurtzite hexagonal structure with the space group P63/mc. FE-SEM images show uniform spherical grains of all Zn1-xFexO nanocrystalline films in which the grain size decreases progressively from 38.85 nm (x = 0.00) to 15.35 nm (x = 0.04). Red shift of the absorption edges is obtained from the optical transmittance spectra from 372 nm of undoped ZnO film to 367 nm of Zn0.96Fe0.04O film. The corresponding wide band gap energy of undoped ZnO film is 3.2986 eV which decreases slightly by 0.0191 eV of Zn0.96Fe0.04O film. The saturation magnetization increases with the increase of Fe concentration. All Fe-doped ZnO films exhibit feromagnetic hysteresis curves which can be well fitted by the law of approaching to saturation with the formula, M = MS (1 − a/Hm).