Structural and luminescence properties of GaN nanowires grown on Si substrate by Au catalyst

The synthesis of hexagonal wurtzite one-dimensional GaN nanowires on Si (111) substrate was investigated using a thermal chemical vapor deposition process. The diameter of the GaN NWs was controlled by varying the growth time using a mixture of GaN powder and gallium metal with the ammonia gas reaction. The grown GaN nanowires exhibited a hexagonal perfect wurtzite structure which has been confirmed by high resolution X-ray diffraction analysis. The morphology and elemental analysis of grown GaN nanowires has been studied by scanning electron microscopy and energy dispersive X-ray analysis. Photoluminescence spectra under the excitation of 244 nm showed a strong near band-edge emission around ~ 372 nm and a broad emission at 450–650 nm related to deep-level defects.