InGaAs/InP core–shell and axial heterostructure nanowires

InGaAs/InP heterostructure nanowires were grown by gas source molecular beam epitaxy on InP (111)B substrates using self-assembled Au particles as a growth catalyst. These structures were analysed by scanning electron microscopy, high resolution transmission electron microscopy, and energy dispersive x-ray spectroscopy. The material interfaces showed significant transition regions and a distinct bulging morphology, attributed to transient group-III material in the Au catalyst. Sidewall growth of InGaAs on InP and a deficiency of Ga in the InGaAs section were observed, and occur due to the shorter surface diffusion length of Ga adatoms compared to In.