Growth of defect-free InAs nanowires using Pd catalyst

To explore the growth mechanism and the effect of non-gold catalysts in growing III-V epitaxial nanowires, InAs nanowires were grown on GaAs(111)B substrates using annealed Pd thin film as catalyst. Through detailed scanning and transmission electron microscopy (SEM/TEM) characterisations, it is found that when the catalyst size is less than 50 nm (from annealing the Pd thin film), defect-free zinc-blende structured epitaxial InAs nanowires are grown along the <;110> directions with four {111} side-facets. The common nanowire/catalyst interface is found to be the unusual {113} planes of the nanowires.