The photoluminescence properties of ZnO:N films fabricated by thermally oxidizing Zn3N2 films using plasma-assisted metal-organic chemical vapour deposition

Nitrogen doped ZnO films are directly fabricated by the thermal oxidation of Zn3N2 films. Zn3N2 films are prepared by plasma-assisted metal-organic chemical vapour deposition (PA-MOCVD). By comparing with undoped ZnO photoluminescence spectra, a much stronger bound exciton emission due to a neutral nitrogen acceptor (A(0)X) is observed at low temperature. The neutral acceptor level is located at 130 meV above the valence band maximum. To demonstrate the quality of ZnO:N thin films as a p-type, a Zn3N2/n-Si heterojunction structure was first fabricated. With an increase of oxidation temperature, the structure has gradually shown p-n junction rectification characteristics from I-V measurements.