Plasma-free nitrogen doping and homojunction light-emitting diodes based on ZnO

The authors develop a plasma-free metalorganic chemical vapour deposition method to grow N-doped p-type ZnO films. The incorporation of the N acceptor and the corresponding change in the Fermi level are well confirmed by x-ray photoelectron spectroscopy. Temperature-dependent photoluminescence reveals the acceptor-related emissions, namely, neutral acceptor-bound exciton and probably donor–acceptor pair transition. In addition, typical rectifying I–V characteristics and room-temperature electroluminescence from ZnO homojunction light-emitting diodes are demonstrated.