Structural and optical properties of sol–gel derived Zn0·8−xNaxMg0·2O thin films

Abstract

Na/Mg co-doped zinc oxide nominally named Zn0·8−xNaxMg0·2O films were prepared on pyrex glass substrates by sol–gel spin-coating method. Effects of Na doping concentration as well as annealing temperature on structural and optical properties of the films were investigated in detail by X-ray diffraction, scanning electron microscopy and photoluminescence spectra. Compared with Zn0·8Mg0·2O films, Na/Mg co-doped zinc oxide films have better c-axis preferred orientation and surface morphology, but these structural properties become worse with increasing x values. There is an optimum annealing temperature for preparation of Zn0·8−xNaxMg0·2O films with excellent characteristics. Under the experimental conditions, Zn0·78Na0·02Mg0·2O films annealed at 560°C have the best c-axis preferred orientation, the most neat and uniform surface morphology as well as the best ultraviolet luminescent property to produce a kind of purple luminescent materials and ultraviolet detector.