The influence of substrate orientation on the density of silicon nanowires grown on multicrystalline and single crystal substrates by electron cyclotron resonance chemical vapour deposition

Autor: J. Ball, H.S. Reehal
Rok vydání: 2012
Předmět:
Zdroj: Thin Solid Films. 520:2467-2473
ISSN: 0040-6090
DOI: 10.1016/j.tsf.2011.10.019
Popis: The Au catalysed, vapour–liquid–solid growth of Si nanowires on Si substrates of different orientations has been studied using electron cyclotron resonance plasma-assisted chemical vapour deposition (ECRCVD). ECRCVD plasma excitation is found to strongly promote wire growth rate and density with wire diameters in excess of 200 nm under the conditions used. Substrate orientation and nanowire density are strongly correlated. This has been studied using multicrystalline as well as single crystal Si substrates. It is suggested that the Gibbs–Thomson effect can account for the behaviour of wire density with orientation. The application of an RF generated, DC self-bias of − 5 V on the substrate during growth strongly enhances wire density without affecting growth rate or diameter. A tentative model for wire growth has been proposed which is based on an initial incubation/crystallisation step, followed by silicon incorporation at the vapour–liquid interface being rate-limiting.
Databáze: OpenAIRE