Structural, optical and photoelectric properties of ZnO:In and Mg _x Zn_{1 -x} O nanofilms prepared by sol-gel method

ZnO, ZnO:In and Mg _x Zn_{1- x} O alloy films with hexagonal wurtzite structures were fabricated using sol-gel method. X-ray diffraction (XRD), UV-Vis absorption spectra and photoluminescence spectra were used to characterize the structural and optical properties of the films. XRD spectra illustrated that no single In₂O₃ or MgO phase was observed for the compound materials. The photoluminescence spectra of ZnO showed a strong UV emission band and a very weak visible emission associated with deep level defects. In incorporation induced the shift of optical band gap, quenching of the near-band-edge emission. The photoelectric conversion properties of ZnO:In nanofilms/SiO₂/Si heterostructures were investigated, which showed a high intensity photocurrent response in the UV and visible region. The Mg _x Zn_{1- x} O films with different x values from 0 to 0.15 were obtained. The intense near-band-edge emissions and weak deep level emissions were observed. The photocurrent properties of Mg_0.15Zn_0.85O nanofilms/SiO₂ were studied.