Impact of deposition methods and doping on structural, optical and electrical properties of ZnO-Al thin films, ISSN 0030-4026

Date Published:

2019

Abstract:

In this work, thin films of aluminum doped ZnO (AZO) were deposited on ultrasonically cleaned glass substrates by sol-gel process using dip and spin coating techniques. For this purpose, Zinc acetate dihydrate, aluminum nitrate nonahydrate, ethanol and mono ethanolamine were employed as precursor, dopant, solvent and stabilizer, respectively. X-ray diffraction, UV–vis, photoluminescence, 4-point probe and Van der pauw techniques were investigated for the characterization of the prepared AZO thin films. X-ray-analysis revealed that all the prepared films have hexagonal wurtzite structure with a relative preferential orientation along the c-axis and the lattice parameters are close to the standard values reported in literature. UV–vis spectroscopy showed that the average value of the films’ transmittance in the visible region is found to be around 85% and the gap ranges in the interval [3.15 eV–3.30 eV]. The photoluminescence spectrum only showed the UV peak while the broad band of the visible region was completely vanished. The electrical measurements indicate that sol-gel methods provide relatively high resistivities compared to those obtained with physical vapor deposition (PVD) techniques.