Germanium nanowires were grown onto Ge(111) substrates by the vapour-liquid-solid process using gold droplets. The growth was carried out in a molecular beam epitaxy chamber at substrate temperatures between 370 and 510C. The resulting nanowire growth rate turned out to be highly dependent upon the substrate temperature exhibiting a maximum at 430C. The temperature dependence of the growth rate could be attributed to surface diffusion both along the substrate and nanowire sidewalls. Analyzing the diffusive material transport yields a diffusion length of 126nm at a substrate temperature of 430C.

Germanium Nanowire Growth Controlled by Surface Diffusion Effects. J.Schmidtbauer, R.Bansen, R.Heimburger, T.Teubner, T.Boeck, R.Fornari: Applied Physics Letters, 2012, 101[4], 043105