Synthesis and field emission properties of triangular-shaped GaN nanowires on Si(1 0 0) substrates

Gallium nitride (GaN) nanowires, grown on gold-coated n-type Si(1 0 0) substrates, were synthesized using the vapor-phase epitaxy method. The grown GaN nanowires, with diameters in the range 20-60 nm and lengths of several micrometers, were uniformly distributed on Si substrates. The GaN nanowires were grown via a vapor-liquid-solid mechanism. The characteristics of the grown GaN were investigated using X-ray diffraction, micro-Raman, and transmission electron microscopy, which found that the GaN nanowires on the Si(1 0 0) are of good crystalline quality. The electron field emission properties of the GaN nanowires (at room temperature) showed a low turn-on field of ∼3.96 V/μm and a field enhancement factor of ∼1050. The sharp ends and rough surfaces of the GaN nanowires are responsible for their good field emission properties.