title: Nucleation and growth of GaN nanowires on Si(111) performed by molecular beam epitaxy.
abstract: GaN nanowires (NWs) have been grown on Si(111) substrates by plasma-assisted molecular beam epitaxy (PAMBE). The nucleation process of GaN-NWs has been investigated in terms of nucleation density and wire evolution with time for a given set of growth parameters. The wire density increases rapidly with time and then saturates. The growth period until the nucleation of new nanowires is terminated can be defined as the nucleation stage. Coalescence of closely spaced nanowires reduces the density for long deposition times. The average size of the well-nucleated NWs shows linear time dependence in the nucleation stage. High-resolution transmission electron microscopy measurements of alternating GaN and AlN layers give valuable information about the length and radial growth rates for GaN and AlN in NWs.
authors.affiliation: Institute of Bio- and Nanosystems (IBN-1) and Center of Nanoelectronic Systems for Information Technology (CNI), Research Centre Jülich GmbH, D-52425 Jülich, Germany. r.calarco@fz-juelich.de
authors.forename: Raffaella
authors.initials: R
authors.lastname: Calarco
authors.forename: Ralph J
authors.initials: RJ
authors.lastname: Meijers
authors.forename: Ratan K
authors.initials: RK
authors.lastname: Debnath
authors.forename: Toma
authors.initials: T
authors.lastname: Stoica
authors.forename: Eli
authors.initials: E
authors.lastname: Sutter
authors.forename: Hans
authors.initials: H
authors.lastname: Lüth
mesh_terms: D003460:Crystallization / Q000379:methods*; D005708:Gallium / Q000737:chemistry*; D020450:Heavy Ions; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008968:Molecular Conformation; D036103:Nanotechnology / Q000379:methods*; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D012825:Silicon / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D046911:Macromolecular Substances; C473348:gallium nitride; D005708:Gallium; D012825:Silicon