Influence of aluminum doping on microstructure, optical and electrical properties of c axis oriented zinc oxide nano films prepared by nebulizer spray pyrolysis technique

Transparent conducting aluminum-doped ZnO thin films have been prepared by nebulizer spray pyrolysis technique for different doping concentrations on glass substrates. X-ray diffraction patterns reveal that all the films are polycrystalline of hexagonal structure with c–axis orientations. Atomic force microscopy (AFM) images noticed that the films have a uniform surface morphology consist spike shaped particles and low surface roughness. The optical transmittance in visible region was escalated from 85 to 93% and optical band gap of thin films is also improved from 3.27 to 3.37 eV. Photoluminescence spectra show mainly five emissions peaks and a blue shift observed in UV emission peak. Hall Effect measurements show that the prepared films having n-type conductivity with low resistivity and high carrier concentrations.