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Thermal and chemical vapor deposition of Si nanowires: Shape control, dispersion, and electrical properties

2007; American Institute of Physics; Volume: 102; Issue: 3 Linguagem: Inglês

10.1063/1.2764050

1520-8850

A. Colli, Andrea Fasoli, Paul Beecher, Peyman Servati, Simone Pisana, Yongqing Fu, Andrew J. Flewitt, W. I. Milne, John Robertson, Caterina Ducati, S. De Franceschi, Stephan Hofmann, A. C. Ferrari,

Semiconductor materials and interfaces

We investigate and compare complementary approaches to SiNW production in terms of yield, morphology control, and electrical properties. Vapor-phase techniques are considered, including chemical vapor deposition (with or without the assistance of a plasma) and thermal evaporation. We report Au-catalyzed nucleation of SiNWs at temperatures as low as 300°C using SiH4 as precursor. We get yields up to several milligrams by metal-free condensation of SiO powders. For all processes, we control the final nanostructure morphology. We then report concentrated and stable dispersions of SiNWs in solvents compatible with semiconducting organic polymers. Finally, we investigate the electrical response of intrinsic SiNWs grown by different methods. All our SiNWs exhibit p-type behavior and comparable performance, though in some cases ambipolar devices are observed. Thus, processing and morphology, rather than the growth technique, are key to achieve optimal samples for applications.