Germanium nanowire growth controlled by surface diffusion effects

Jan Schmidtbauer, Roman Bansen, Robert F. Heimburger, Thomas Teubner, Torsten Boeck, R. Fornari

Applied Physics Letters · 2012 · 14 citations · 17 references

Concepts

Abstract

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

References

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