An approach to investigate the structural, morphological, and optical properties of spray pyrolyzed B and Mg co-doped ZnO thin films

Abstract

Thin films of Boron (B) and Magnesium (Mg) co-doped Zinc Oxide (BMZO) were produced by spray pyrolysis on a glass substrate at a temperature of 350 °C. This study considers BZO as the base material and then varies the Mg (as dopant) percentage to produce BMZO thin films. The surface morphology and structural aspects of the films are affected by different doping concentrations. By altering the Mg (dopant) content between 1%, 3%, and 5%, the influence of varied doping concentrations on the surface morphology and structural properties of the BMZO thin films was examined and discussed. Scanning Electron Microscopy (SEM) and X-ray diffraction (XRD) were used to investigate the surface morphology and structural characteristics of the synthesized films. All ZnO films, according to X-ray diffraction, are polycrystalline and preferred orientations along the (100), (002), (101), (102), and (110). The prominent peak orientation of the crystal was in the (002) direction. A typical hexagonal wurtzite structure was identified in the films, with crystallite sizes ranging from 6.12 to 13.5 nm. The Crystallite size increased with Mg doping up to a certain threshold (3% Mg doping), and then decreased with more doping. According to SEM results, nano-fiber diameter and area grew when Mg concentration in MgxB.03Zn.97-xO (BMZO) increased and subsequently decreased at 5% Mg-doped BZO. The optical characterization was done using a UV–Visible spectrophotometer. Transparency of the films was very high (above 90%) in the ultraviolet range of spectral for 3% Mg-doped BZO with a corresponding band-gap was 3.28 eV. Transparency reduced slightly for 1% Mg-doped and undoped BZO with increasing deposition concentration, while it decreased significantly for 5% Mg-doped BZO.