title: Growth by molecular beam epitaxy and properties of inclined GaN nanowires on Si(001) substrate.
abstract: The growth mode and structural and optical properties of novel type of inclined GaN nanowires (NWs) grown by plasma-assisted MBE on Si(001) substrate were investigated. We show that due to a specific nucleation mechanism the NWs grow epitaxially on the Si substrate without any Si(x)N(y) interlayer, first in the form of zinc-blende islands and then as double wurtzite GaN nanorods with Ga-polarity. X-ray measurements show that orientation of these nanowires is epitaxially linked to the symmetry of the substrate so that [0001] axis of w-GaN nanowire is directed along the [111]Si axis. This is different from commonly observed behavior of self-induced GaN NWs that are N-polar and grow perpendicularly to the surface of nitridized silicon substrate independently on its orientation. The inclined NWs exhibit bright luminescence of bulk donor-bound excitons (D(0)X) at 3.472 eV and exciton-related peak at 3.46 eV having a long lifetime (0.7 ns at 4 K) and observable up to 50 K.
authors.affiliation: Institute of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, 02-668 Warsaw, Poland. Faculty of Physics, University of Warsaw, Hoza 69, 00-681 Warsaw, Poland.
authors.forename: J
authors.initials: J
authors.lastname: Borysiuk
authors.forename: Z R
authors.initials: ZR
authors.lastname: Zytkiewicz
authors.forename: M
authors.initials: M
authors.lastname: Sobanska
authors.forename: A
authors.initials: A
authors.lastname: Wierzbicka
authors.forename: K
authors.initials: K
authors.lastname: Klosek
authors.forename: K P
authors.initials: KP
authors.lastname: Korona
authors.forename: P S
authors.initials: PS
authors.lastname: Perkowska
authors.forename: A
authors.initials: A
authors.lastname: Reszka