Fabrication and characterization of p-type ZnO nano-thin films prepared by in situ oxidation of sputtered Zn3N2

The precursor Zn₃N₂ films were deposited on quartz glass substrates by reactive DC magnetron sputtering and oxidized in situ at various temperatures by introducing pure oxygen gas directly into the deposition chamber. X-ray diffraction (XRD), scanning electron microscopy (SEM), UVNIS transmittance, Hall-effect measurements and photoluminescence (PL) were carried out to investigate the structural, optical and electrical properties of the samples. The results showed that the properties of ZnO:N films strongly depended on the oxidation temperature and duration. By optimizing the oxidization conditions, high-quality p-type ZnO:N films with c-axis preferential orientation were obtained. Hall effect measurement results showed that the ZnO:N films oxidized at 500degC had a resistivity of 0.7 Omega-cm, a hole concentration of 6.2times10¹⁸cm^-3 and a mobility of 4.95 cm²/Vldrs while the films still showed high transmittance in the visible region and strong excitonic UV emission at 387 nm.