Tailoring the structural and optical properties of Mg-doped ZnO Thin films via sol-gel spin coating for ultraviolet optoelectronics

OpenAlex İngilizce

Abstract This study reports the characterization of undoped and Mg-doped zinc oxide (ZnO) thin films obtained using the sol–gel spin-coating method. Zn 1-x Mg x O films with x = 0, 0.01, 0.03, 0.05, and 0.07 were successfully deposited onto glass substrates. X-ray Diffraction analysis confirmed that films crystallized in the hexagonal wurtzite structure, with no secondary phases detected, indicating successful incorporation of Mg. Structural analysis revealed a systematic decrease in lattice parameters with increasing Mg content, consistent with the substitution of larger Zn ions by smaller Mg ions. Optical properties were investigated using absorption and photoluminescence spectroscopies. Absorption results demonstrated a significant blue-shift of the absorption edge with increasing Mg concentration, leading to a tunable optical bandgap that expanded from approximately 3.28 eV for undoped ZnO to 3.37 eV for the highest Mg doping (7%). Photoluminescence spectra exhibited near-band-edge ultraviolet emission, whose intensity was notably enhanced at optimal Mg doping levels, suggesting improved optical quality. These findings underscore the effectiveness of Mg doping via the sol–gel route in precisely tailoring thecharacteristics of ZnO thin films, making them candidates for optoelectronic applications.