Effect of multiple-step annealing on the structural, optical and electrical properties of ZnO:In-N films

Abstract The intrinsic defects in ZnO:In-N films can be regulated efficiently by multiple-step annealing together with the ambient atmosphere. Correspondingly, the conductivity of films changes from n to p-type, then to n-type (n → p → n). The experimental results indicate high-quality films annealed at 600 °C for 8 min in N2 ambience can be obtained by the analysis of X-ray diffraction (XRD) patterns and the concentrations of donor defects (Zni, VO) are dramatically decreased from Raman and photoluminescence (PL) spectra. When the films are further annealed in air for 3 min, the concentrations of acceptors such as oxygen interstitials (Oi) are increased slightly. Meanwhile, N-related acceptor complexes in the films are dominantly activated in terms of relative X-ray photoelectron spectroscopy (XPS) peak area ratio of P1 (395.5 eV) and P2 (397.3 eV) to P3 (403.5 eV), which plays an important role in realizing the conversion of the ZnO p-type conductivity. Noted that the p-type ZnO:In-N films with the hole concentration of 1017 cm−3 can be obtained in this way.