Room temperature electroluminescence from the ZnO homojunction grown on an n+-Si substrate by metal–organic chemical vapor deposition

ZnO film was grown on a heavily phosphor-doped n+-Si substrate by metal–organic chemical vapor deposition technology. X-ray photoelectron spectroscopy measurements indicate that a two-layer structure, comprised of a phosphor-doped ZnO layer and an un-doped ZnO layer, was formed during the diffusion process of phosphor from the n+-Si substrate. The current–voltage characteristic exhibited significant rectifying behavior with low-leakage current for this device. The distinct defect-related blue–white electroluminescence was observed, the origin of which was confirmed to be from the ZnO p–n homojunction.