Sidewall evolution in VLS grown GaAs nanowires

The sidewalk of Au-catalysed GaAs nanowires are studied systematically by using transmission electron microscopy. The cross-sectional shape of the VLS grown nanowires was found to consist of 3 curved surfaces along {112}A. The curved surfaces evolve into three {112}A and three {112}B facets towards the base of the nanowire due to the radial growth around the nanowire. These sidewalls transform to {110} facets at high temperature annealing and the transformation rate is determined by the cross-sectional shape and size of the nanowires.