Growth of Nb-catalysed GaN nanowires

GaN nanowires have been successfully synthesized on Si(1 1 1) substrate by ammoniating Ga2O3 films at 950 °C. The structure and morphology of GaN nanowires are characterized by X-ray diffraction, scanning electron microscopy, field-emission transmission electron microscope and X-ray photoelectron spectroscopy. The results show that the synthesized nanowires are single-crystal hexagonal wurtzite GaN with diameters ranging from 50 to 100 nm and lengths up to several microns. Finally, the growth mechanism of GaN nanowires is explored.