Bismuth catalyzed growth of GaAsBi nanowires by metalorganic vapor phase epitaxy

Abstract We report the synthesis of GaAsBi nanowires using Bi as catalyst. Nanoislands of bismuth are grown on GaAs substrates by atmospheric pressure metalorganic vapor phase epitaxy, these acts appear as local points of the nucleus for the growth of the GaAsBi nanowires. Catalysis by the metal droplet can make growth possible at low temperatures. Surface morphology of the elaborated samples is investigated using scanning electron microscopy. The growth of the nanowires at low temperature results in round Bi-rich balls can be found on the tips of all nanostructures. The growth conditions affect the initial nucleation of GaAsBi structures, resulting in different numbers and shapes of nanowires. The bases of the tapered structures can be quite large. Likewise, the growth conditions have also a great impact on the orientation and structural quality of the nanowires.