Studying ZnO:Al's Structural and Optical Characteristics by Chemical Spray Pyrolysis Method

Abstract

In this study, pure zinc oxide films doped with (Al) were prepared by spray pyrolysis technique, with percentages of (3,5 and 7%) and molar concentrations (0.05), on glass substrates at a temperature of (350 ^oC). X-ray diffraction pattern showed that pure zinc oxide films are all polycrystalline and have a hexagonal structure with a preferred growth direction (002). Using atomic force microscopy (AFM), the surface topography of the produced films was investigated. The findings that emerged from the analysis demonstrated a reduction in the membrane's surface roughness after doping as well as a reduction in particle size (126-55.64nm). Besides, the scanning electron microscopy (FE-SEM) results of all generated films were examined and reviewed in order to understand the composition of their surfaces and to determine the particle size, in order that practically all surfaces are covered with the spherical particles, which are collected longitudinally into ribbon-like structures linked to one another. On the other hand, optical properties have shown that the values of the energy gap for direct transitions increased from (3.73 eV) for pure films to (3.80 eV) for aluminum doped films. The optical properties investigation included transmittance spectrum, absorption coefficient and energy gap. The transmittance (89%) was within the visible spectrum region.