Fabrication and characterization of vertically aligned ZnMgO/ZnO nanowire arrays

A new method for fabricating large-area well-aligned ZnMgO nanowire arrays, using radio frequency (RF) magnetron co-sputtering, is reported. ZnO nanowire arrays, prepared by metal organic chemical vapor deposition (MOCVD), were used as seed layers for ZnMgO nanowires. For the fabrication of ZnMgO nanowires, RF powers and sputtering pressure were varied to control the supersaturation condition and the kinetic energies of the sputtered materials. Vertically aligned ZnMgO nanowires with [0 0 0 1] preferred orientation were obtained at a working pressure of 20 × 10−3 Torr, RF power of 50 W and 15 W for ZnO and Mg targets, respectively. Crystallinity of the nanostructures were improved with rapid thermal annealing (RTA) at 900 °C. Furthermore, the blue shift in the near-band-edge emission of RTA-treated ZnMgO nanowires was observed during photoluminescence study.