Investigation of the formation of nanowires from silicon whiskers

Nanowires have been prepared by the high-temperature oxidation of Si whiskers. The dependences of the nanowire formation on the oxidation parameters have been investigated. The oxidation rate is shown to depend on the whisker diameter. Oxidation in dry oxygen at temperatures no higher than 950°C results in self-stopping; i.e., the nanowire diameter is stabilized. Stabilization is not observed at oxidation temperatures above 950°C or at oxidation in wet oxygen. Oxidation at higher temperatures made it possible to obtain nanowires ≤5 nm in diameter in relatively thick (up to 200 nm in diameter) whiskers.