Growth of GaN nanorods prepared by ammoniating Ga2O3/ZnO films on Si substrates and their properties: Structure, morphology, chemical state and photoluminescence

Large quantities of GaN nanorods have been successfully synthesized on Si(1 1 1) substrates by magnetron sputtering through ammoniating the Ga2O3/ZnO films at 950 °C in a quartz tube. The GaN nanorods are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), a field-emission transmission electron microscope (FETEM), a Fourier transform infrared (FTIR) spectrophotometer and a fluorescence spectrophotometer. The results show that the nanorods have pure hexagonal GaN wurtzite structure, with lengths of about several micrometers and diameters of about 200 nm. The clear lattice fringes demonstrate that the synthesized nanorods are single-crystal GaN. The FTIR spectrum further confirms that the GaN is obtained under this condition. The representative photoluminescence spectrum at room temperature exhibited a strong emission peak at 375.7 nm and two weak emission peaks at 436.2 and 475.5 nm. The GaN nanorods show a very good emission property, which will have a good advantage for applications in laser device using one-dimensional structures. Finally, the growth mechanism is also briefly discussed.