Study of Erbium Doping Effect on Structural, Morphological and Optical Properties of Dip Coated ZnO Under Alkaline Conditions

Abstract

Undoped Zinc oxide (ZnO) and erbium (Er) doped ZnO thin films have been grown on glass substrate by dip coating technique under alkaline conditions (pH 9). The pH was maintained at 9 for all prepared sols by controlling the amount of Monoethanolamine (MEA). The eff ;ects of Er doping concentration on the ZnO films properties was studied by using XRD, SEM, EDX, AFM, Raman spectroscopy, FTIR analysis and UV–vis spectrophotometer. The results showed that the incorporation of Er3+ under alkaline pH had a great effect on the ZnO properties. All samples exhibit a pure ZnO polycrystalline hexagonal wurtzite structure with a high crystalline quality. Homogenous, smooth and dense granular morphology nanostructures were revealed by AFM and SEM analysis. Raman spectroscopy and FTIR analysis confirm the formation of ZnO hexagonal wurtzite structure for samples. It was found that Er doping concentration enhance optical transmittance of ZnO based thin films. A red-shift was observed in the band gap of Er doped ZnO films with increasing Er concentration. The obtained results make EZO based thin films suitable for solar cells applications.