Se concentration dependent band gap engineering in ZnO1-xSex thin film for optoelectronic applications

ZnO1-xSex films with various selenium concentrations are deposited on the sapphire substrate (0 0 0 1) by pulsed laser deposition technique. Structural properties of the thin films studied by X-ray diffraction (XRD) and chemical bonding studied by X-ray photoelectron spectroscopy (XPS) reveals that Se is substituted in O site during the growth of ZnO1-xSex films. Optical properties are analyzed by UV-Visible spectrometer. From the plot for (αhυ)2 vs photon energy, it is inferred that the band gap energy of ZnO1-xSex gradually reduces to 2.85 eV with increasing Se concentration.