title: Three-dimensional multiple-order twinning of self-catalyzed GaAs nanowires on Si substrates.
abstract: In this paper we introduce a new paradigm for nanowire growth that explains the unwanted appearance of parasitic nonvertical nanowires. With a crystal structure polarization analysis of the initial stages of GaAs nanowire growth on Si substrates, we demonstrate that secondary seeds form due to a three-dimensional twinning phenomenon. We derive the geometrical rules that underlie the multiple growth directions observed experimentally. These rules help optimizing nanowire array devices such as solar or water splitting cells or of more complex hierarchical branched nanowire devices.
authors.affiliation: Laboratoire des Matériaux Semiconducteurs, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland.
authors.forename: Emanuele
authors.initials: E
authors.lastname: Uccelli
authors.forename: Jordi
authors.initials: J
authors.lastname: Arbiol
authors.forename: Cesar
authors.initials: C
authors.lastname: Magen
authors.forename: Peter
authors.initials: P
authors.lastname: Krogstrup
authors.forename: Eleonora
authors.initials: E
authors.lastname: Russo-Averchi
authors.forename: Martin
authors.initials: M
authors.lastname: Heiss
authors.forename: Gabriel
authors.initials: G
authors.lastname: Mugny
authors.forename: François
authors.initials: F
authors.lastname: Morier-Genoud
authors.forename: Jesper
authors.initials: J
authors.lastname: Nygård
authors.forename: Joan Ramon
authors.initials: JR
authors.lastname: Morante
authors.forename: Anna
authors.initials: A
authors.lastname: Fontcuberta I Morral