Advanced Functional Materials, Vol.25, No.14, 2182-2188, 2015
White Light-Emitting Diode From Sb-Doped p-ZnO Nanowire Arrays/n-GaN Film
A whole interfacial transition of electrons from conduction bands of n-type material to the acceptor levels of p-type material makes the energy band engineering successful. It tunes intrinsic ZnO UV emission to UV-free and warm white light-emitting diode (W-LED) emission with color coordinates around (0.418, 0.429) at the bias of 8-15.5 V. The W-LED is fabricated based on antimony (Sb) doped p-ZnO nanowire arrays/Si doped n-GaN film heterojunction structure through one-step chemical vapor deposition with quenching process. Element analysis shows that the doping concentration of Sb is = 1.0%. The I-V test exhibits the formation of p-type ZnO nanowires, and the temperature-dependent photoluminescence measurement down to 4.65 K confirms the formation of deep levels and shallow acceptor levels after Sb-doping. The intrinsic UV emission of ZnO at room temperature is cut off in electroluminescence emission at a bias of 4-15.5 V. The UV-free and warm W-LED have great potential application in green lights program, especially in eye-protected lamp and display since television, computer, smart phone, and mobile digital equipment are widely and heavily used in modern human life, as more than 3000 h per year.