Electroluminescence of the p-ZnO:As/n-ZnO LEDs grown on ITO glass coated with GaAs interlayer

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.