Optical and field emission performances of bamboo shoot-shaped GaN nanowires

Abstract

Novel single-crystalline bamboo shoot-shaped gallium nitride (GaN) nanowires were prepared on silicon substrates using Ga2O3 and ammonia (NH3) by chemical vapor deposition (CVD) method. From the view morphology of bamboo shoot-shaped GaN nanowires, it can be seen that the average diameter of sample is 200 nm, and along the axial direction to the tip diameter decreases slowly. The growth mechanism of bamboo shoot-shaped GaN nanowires obeys the vapor-liquid-solid (VLS) mechanism. In addition, field emission tests indicate that the turn on field of bamboo shoot-shaped GaN nanowires is 7.5 V/μm (at the current density of 10 μA/cm2), with field enhancement factor of 646, which is sufficient meets the field emission device and vacuum microelectronic device. Moreover, the photoluminescence (PL) spectrum measurement shows that the main luminescence peak of bamboo shoot-shaped GaN nanowires is at 364 nm (3.41 eV), which indicate the bamboo shoot-shaped GaN nanowires can be used for preparation flexible optoelectronic devices.