Catalyst-free Growth of Single-Crystal Silicon and Germanium Nanowires

• Published in: Nano letters 2009-02, Vol.9 (2), p.864-869
• Main Authors: Kim, Byung-Sung, Koo, Tae-Woong, Lee, Jae-Hyun, Kim, Duk Soo, Jung, Young Chai, Hwang, Sung Woo, Choi, Byoung Lyong, Lee, Eun Kyung, Kim, Jong Min, Whang, Dongmok
• Format: Article
• Language: English
• Subjects: Catalytic methods; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronic transport in multilayers, nanoscale materials and structures; Exact sciences and technology; Materials science; Methods of nanofabrication; Nanocrystalline materials; Nanoscale materials and structures: fabrication and characterization; Physics; Quantum wires
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/nl803752w

We report metal-free synthesis of high-density single-crystal elementary semiconductor nanowires with tunable electrical conductivities and systematic diameter control with narrow size distributions. Single-crystal silicon and germanium nanowires were synthesized by nucleation on nanocrystalline seeds and subsequent one-dimensional anisotropic growth without using external catalyst. Systematic control of the diameters with tight distribution and tunable doping concentration were realized by adjusting the growth conditions, such as growth temperature and ratio of precursor partial pressures. We also demonstrated both n-type and ambipolar field effect transistors using our undoped and phosphorus-doped metal-free silicon nanowires, respectively. This growth approach offers a method to eliminate potential metal catalyst contamination and thus could serve as an important point for further developing nanowire nanoelectronic devices for applications.