Self-Catalyzed Growth of InAs Nanowires on Graphene by MBE

We used epitaxial graphene obtained via thermal decomposition of silicon carbide (SiC) to grow InAs nanowires in a high purity MBE system. We studied the effect of the growth parameters (substrate nucleation and growth temperature, indium and arsenic fluxes) on the nanowires density, aspect ratio morphology and crystal structure. The nucleation turns out to be quite easily facilitated, and the growth quite readily guided by an indium droplet as observed by SEM, an essential requirement for obtaining a pure crystal structure. TEM exposes a mixed structure yet suffering from a large number of lattice rotations which besides the relatively large diameter we relate to fluctuations in supersaturation associated with the relatively low density.