Effect of reactor pressure on catalyst composition and growth of GaSb nanowires

Au-assisted metalorganic chemical vapor deposition was employed for the synthesis of GaSb nanowires. X-ray energy dispersive spectrometry indicates that the composition of catalyst particles depends on the reactor pressure at constant growth temperature and V/III ratio. The catalyst particles were ternary Au–Ga–Sb alloys for nanowires grown at 100 and 200 Torr, suggesting a vapor–liquid–solid (VLS) nanowire growth mechanism. At 300 Torr, the catalyst particles were pure Ga and the self-catalytic VLS mechanism was responsible for the growth of the GaSb nanowires. The diameter and growth rate of the nanowires, as well as the contact angle between the catalyst particle and the nanowire, were found to be dependent on the composition of the catalyst particles.