In this paper, we proposed a new p-type ZnO doping method with metal organic chemical vapor deposition (MOCVD) technology by inserting a GaAs interlayer between substrate and ZnO epitaxial layer. The doping concentration of p-type ZnO film is able to be controlled by adjusting the thickness of the GaAs interlayer. With this method, we fabricated n-ZnO/p-ZnO: As homojunction light-emitting diode (LED) on ITO-glass substrate pre-coated with 20 nm GaAs interlayer. The device exhibits a typical rectifying behavior by current-voltage (I-V) measurement. When the device is forward biased, UV-vis electroluminescence (EL) emissions can be observed clearly. (C) 2010 Elsevier B. V. All rights reserved.