Influence of Pressure on Silicon Nanowire Growth Kinetics

Abstract

Si nanowire growth kinetics was studied, and the growth rate was shown to be highly sensitive to SiH4 precursor pressures, changing from a second-order dependence at low pressures to first-order and then independent at high pressures. Molecular collisions of SiH4 with He carrier gas account for this finding. The second- and first-order correlation was explained by the unimolecular reaction model and the saturated growth rate was due to the Langmuir adsorption limit. Our results suggest that precursor pressures must be controlled carefully for desired growth kinetics.