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arXiv · 1208.0666

Monolithic growth of ultra-thin Ge nanowires on Si(001)

Jianjun Zhang·Georgios Katsaros·Francesco Montalenti·Daniele Scopece·Roman O. Rezaev·Christine Mickel·Bernd Rellinghaus·Leo Miglio·Silvano De Franceschi·Armando Rastelli·Oliver G. Schmidt
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Abstract

Self-assembled Ge wires with a height of only 3 unit cells and a length of up to 2 micrometers were grown on Si(001) by means of a catalyst-free method based on molecular beam epitaxy. The wires grow horizontally along either the [100] or the [010] direction. On atomically flat surfaces, they exhibit a highly uniform, triangular cross section. A simple thermodynamic model accounts for the existence of a preferential base width for longitudinal expansion, in quantitative agreement with the experimental findings. Despite the absence of intentional doping, first transistor-type devices made from single wires show low-resistive electrical contacts and single hole transport at sub-Kelvin temperatures. In view of their exceptionally small and self-defined cross section, these Ge wires hold promise for the realization of hole systems with exotic properties and provide a new development route for silicon-based nanoelectronics.

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Jianjun Zhang, Georgios Katsaros, Francesco Montalenti, Daniele Scopece, Roman O. Rezaev, Christine Mickel, Bernd Rellinghaus, Leo Miglio, Silvano De Franceschi, Armando Rastelli, Oliver G. Schmidt. 2012-08-03. Monolithic growth of ultra-thin Ge nanowires on Si(001). https://doi.org/10.1103/physrevlett.109.085502

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