Figure 1.

SEM micrographs of GaAs nanowires grown on GaAs (111)B substrates: a from colloidal nanoparticles with 150 nm diameter under TESn supply (IV/III = 0.08), b from colloidal nanoparticles with 150 nm diameter under DitBuSi supply (IV/III = 0.52), c grown under the same conditions as in a but from polydisperse seed particles formed by annealing of a 2.5 nm Au layer. The different nanowire density in a and b is just accidental.

Gutsche et al. Nanoscale Res Lett 2011 6:65   doi:10.1007/s11671-010-9815-7