title: Growth Mechanisms of Inductively-Coupled Plasma Torch Synthesized Silicon Nanowires and their associated photoluminescence properties.
abstract: Ultra-thin Silicon Nanowires (SiNWs) were produced by means of an industrial inductively-coupled plasma (ICP) based process. Two families of SiNWs have been identified, namely long SiNWs (up to 2-3 micron in length) and shorter ones (~100 nm). SiNWs were found to consist of a Si core (with diameter as thin as 2 nm) and a silica shell, of which the thickness varies from 5 to 20 nm. By combining advanced transmission electron microscopy (TEM) techniques, we demonstrate that the growth of the long SiNWs occurred via the Oxide Assisted Growth (OAG) mechanism, while the Vapor Liquid Solid (VLS) mechanism is responsible for the growth of shorter ones. Energy filtered TEM analyses revealed, in some cases, the existence of chapelet-like Si nanocrystals embedded in an otherwise silica nanowire. Such nanostructures are believed to result from the exposure of some OAG SiNWs to high temperatures prevailing inside the reactor. Finally, the intense photoluminescence (PL) of these ICP-grown SiNWs in the 620-950 nm spectral range is a clear indication of the occurrence of quantum confinement. Such a PL emission is in accordance with the TEM results which revealed that the size of nanostructures are indeed below the exciton Bohr radius of silicon.
authors.affiliation: Dipartimento di Fisica e Astronomia, Università di Catania, Via S. Sofia 64, I-95123 Catania, Italy.|CNR IMM-MATIS, Via S. Sofia 64, I-95123 Catania, Italy.|Institut national de la recherche scientifique, Centre-Énergie, Matériaux et Télécommunications, 1650 Blvd. Lionel Boulet, Varennes, QC, J3X 1S2, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Agati
authors.affiliation: CNR IMM-MATIS, Via S. Sofia 64, I-95123 Catania, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Amiard
authors.affiliation: Institut national de la recherche scientifique, Centre-Énergie, Matériaux et Télécommunications, 1650 Blvd. Lionel Boulet, Varennes, QC, J3X 1S2, Canada.
authors.forename: V
authors.initials: V
authors.lastname: Le Borgne
authors.affiliation: Dipartimento di Fisica, Università di Roma "Tor Vergata", Via della Ricerca Scientifica 1, Roma, 00133, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Castrucci
authors.affiliation: Tekna Plasma Systems Inc., 2935 Industrial Blvd., Sherbrooke, QC, J1L 2T9, Canada.
authors.forename: R
authors.initials: R
authors.lastname: Dolbec
authors.affiliation: Dipartimento di Fisica, Università di Roma "Tor Vergata", Via della Ricerca Scientifica 1, Roma, 00133, Italy.
authors.forename: M
authors.initials: M
authors.lastname: De Crescenzi
authors.affiliation: Institut national de la recherche scientifique, Centre-Énergie, Matériaux et Télécommunications, 1650 Blvd. Lionel Boulet, Varennes, QC, J3X 1S2, Canada.
authors.forename: M A
authors.initials: MA
authors.lastname: El Khakani
authors.affiliation: CNR IMM-MATIS, Via S. Sofia 64, I-95123 Catania, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Boninelli