title: Fast growth synthesis of GaAs nanowires with exceptional length.
abstract: We report the first synthesis of GaAs nanowires (NWs) by Au-assisted vapor-liquid-solid (VLS) growth in the novel hydride vapor phase epitaxy (HVPE) environment. Forty micrometer long rodlike <111> monocrystalline GaAs nanowires exhibiting a cubic zinc blende structure were grown in 15 min with a mean density of 10(6) cm(-2). The synthesis of such long figures in such a short duration could be explained by the growth physics of near-equilibrium HVPE. VLS-HVPE is mainly based on solidification after direct and continuous feeding of the arsenious and GaCl growth precursors through the Au-Ga liquid catalyst. Fast solidification (170 microm/h) is then assisted by the high decomposition frequency of GaCl. This predominant feeding through the liquid-solid interface with no mass and kinetic hindrance favors axial rather than radial growth, leading to twin-free nanowires with a constant cylinder shape over unusual length. The achievement of GaAs NWs several tens of micrometers long showing a high surface to volume ratio may open the field of III-V wires, as already addressed with ultralong Si nanowires.
authors.affiliation: Clermont Université, Université Blaise Pascal, LASMEA, BP 10448, Clermont-Ferrand, France.
authors.forename: M R
authors.initials: MR
authors.lastname: Ramdani
authors.forename: E
authors.initials: E
authors.lastname: Gil
authors.forename: Ch
authors.initials: Ch
authors.lastname: Leroux
authors.forename: Y
authors.initials: Y
authors.lastname: André
authors.forename: A
authors.initials: A
authors.lastname: Trassoudaine
authors.forename: D
authors.initials: D
authors.lastname: Castelluci
authors.forename: L
authors.initials: L
authors.lastname: Bideux
authors.forename: G
authors.initials: G
authors.lastname: Monier
authors.forename: C
authors.initials: C
authors.lastname: Robert-Goumet
authors.forename: R
authors.initials: R
authors.lastname: Kupka
mesh_terms: D001152:Arsenicals / Q000138:chemical synthesis*; D003460:Crystallization / Q000379:methods*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005708:Gallium; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D013499:Surface Properties
chemical_list: D001152:Arsenicals; D046911:Macromolecular Substances; C043055:gallium arsenide; D005708:Gallium