To have a clear insight into the nanowire formation upon catalyst assistant chemical vapor deposition (CCVD), we performed the general thermodynamic and kinetic approaches on nanoscale to elucidate the nanowire nucleation in CCVD with respect to the capillary effect of the nanosized curvature of nanowire nuclei in the initial growing. For the issue of catalyst nanoparticles on nanowires tip or substrate, we deduced the nucleation thermodynamic criteria and diffusion kinetic criteria on the basis of the proposed thermodynamic and kinetic analyses on nanoscale. Taking Si nanowires as the example, we compared the experimental data with the theoretical predictions, and found that they are consistent. We expected that the thermodynamic and kinetic criteria at the nanometer scale to be a general approach applicable to understand nanowires formation in CCVD.

• Received 22 January 2005

DOI:https://doi.org/10.1103/PhysRevB.72.085417