title: Crystal Phases in Hybrid Metal-Semiconductor Nanowire Devices.
abstract: We investigate the metallic phases observed in hybrid metal-GaAs nanowire devices obtained by controlled thermal annealing of Ni/Au electrodes. Devices are fabricated onto a SiN membrane compatible with transmission electron microscopy studies. Energy dispersive X-ray spectroscopy allows us to show that the nanowire body includes two Ni-rich phases that thanks to an innovative use of electron diffraction tomography can be unambiguously identified as Ni3GaAs and Ni5As2crystals. The mechanisms of Ni incorporation leading to the observed phenomenology are discussed.
authors.affiliation: Center for Nanotechnology Innovation @NEST, Istituto Italiano di Tecnologia , Piazza San Silvestro 12, 56127 Pisa, Italy.
authors.forename: J
authors.initials: J
authors.lastname: David
authors.affiliation: NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR , Piazza S. Silvestro 12, I-56127 Pisa, Italy.
authors.forename: F
authors.identifier: 0000-0002-0601-4927
authors.initials: F
authors.lastname: Rossella
authors.affiliation: NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR , Piazza S. Silvestro 12, I-56127 Pisa, Italy.
authors.forename: M
authors.identifier: 0000-0002-3907-5275
authors.initials: M
authors.lastname: Rocci
authors.affiliation: NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR , Piazza S. Silvestro 12, I-56127 Pisa, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Ercolani
authors.affiliation: NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR , Piazza S. Silvestro 12, I-56127 Pisa, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Sorba
authors.affiliation: NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR , Piazza S. Silvestro 12, I-56127 Pisa, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Beltram
authors.affiliation: Center for Nanotechnology Innovation @NEST, Istituto Italiano di Tecnologia , Piazza San Silvestro 12, 56127 Pisa, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Gemmi
authors.affiliation: NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR , Piazza S. Silvestro 12, I-56127 Pisa, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Roddaro
keywords: Electron diffraction tomography; GaAs nanowires; hybrid metal−semiconductor nanowires; thermal annealing; transmission electron microscopy