title: Synthesis, Morphological, and Electro-optical Characterizations of Metal/Semiconductor Nanowire Heterostructures.
abstract: In this letter, we demonstrate the formation of unique Ga/GaAs/Si nanowire heterostructures, which were successfully implemented in nanoscale light-emitting devices with visible room temperature electroluminescence. Based on our recent approach for the integration of InAs/Si heterostructures into Si nanowires by ion implantation and flash lamp annealing, we developed a routine that has proven to be suitable for the monolithic integration of GaAs nanocrystallite segments into the core of silicon nanowires. The formation of a Ga segment adjacent to longer GaAs nanocrystallites resulted in Schottky-diode-like I/V characteristics with distinct electroluminescence originating from the GaAs nanocrystallite for the nanowire device operated in the reverse breakdown regime. The observed electroluminescence was ascribed to radiative band-to-band recombinations resulting in distinct emission peaks and a low contribution due to intraband transition, which were also observed under forward bias. Simulations of the obtained nanowire heterostructure confirmed the proposed impact ionization process responsible for hot carrier luminescence. This approach may enable a new route for on-chip photonic devices used for light emission or detection purposes.
authors.affiliation: Institute of Solid State Electronics, TU Wien , Floragasse 7, 1040 Wien, Austria.
authors.forename: Markus
authors.initials: M
authors.lastname: Glaser
authors.affiliation: Institute of Solid State Electronics, TU Wien , Floragasse 7, 1040 Wien, Austria.
authors.forename: Andreas
authors.initials: A
authors.lastname: Kitzler
authors.affiliation: Institute for Solid State Physics, Friedrich-Schiller-University Jena , Max-Wien-Platz 1, 07743 Jena, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Johannes
authors.affiliation: Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf , Bautzner Landstraße 400, 01328 Dresden, Germany.
authors.forename: Slawomir
authors.initials: S
authors.lastname: Prucnal
authors.affiliation: Laboratoire des Matériaux Semiconducteurs, Ecole Polytechnique Fédérale de Lausanne , 1015 Lausanne, Switzerland.
authors.forename: Heidi
authors.initials: H
authors.lastname: Potts
authors.affiliation: Laboratoire des Matériaux Semiconducteurs, Ecole Polytechnique Fédérale de Lausanne , 1015 Lausanne, Switzerland.
authors.forename: Sonia
authors.initials: S
authors.lastname: Conesa-Boj
authors.affiliation: Institute for Microelectronics, TU Wien , Gußhausstraße 25-29, 1040 Wien, Austria.
authors.forename: Lidija
authors.initials: L
authors.lastname: Filipovic
authors.affiliation: Institute for Microelectronics, TU Wien , Gußhausstraße 25-29, 1040 Wien, Austria.
authors.forename: Hans
authors.initials: H
authors.lastname: Kosina
authors.affiliation: Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf , Bautzner Landstraße 400, 01328 Dresden, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Skorupa
authors.affiliation: Institute of Solid State Electronics, TU Wien , Floragasse 7, 1040 Wien, Austria.
authors.forename: Emmerich
authors.initials: E
authors.lastname: Bertagnolli
authors.affiliation: Institute for Solid State Physics, Friedrich-Schiller-University Jena , Max-Wien-Platz 1, 07743 Jena, Germany.
authors.forename: Carsten
authors.initials: C
authors.lastname: Ronning
authors.affiliation: Laboratoire des Matériaux Semiconducteurs, Ecole Polytechnique Fédérale de Lausanne , 1015 Lausanne, Switzerland.
authors.forename: Anna
authors.initials: A
authors.lastname: Fontcuberta I Morral
authors.affiliation: Institute of Solid State Electronics, TU Wien , Floragasse 7, 1040 Wien, Austria.
authors.forename: Alois
authors.initials: A
authors.lastname: Lugstein
keywords: GaAs; Nanowires; Schottky; Si; electroluminescence; heterostructures