title: Raman scattering study of GaN nanostructures obtained by bottom-up and top-down approaches.
abstract: GaN nanocolumnar structures were grown by plasma-assisted molecular beam epitaxy (PAMBE) and also fabricated by electron cyclotron resonance reactive ion etching (ECR-RIE) of a compact GaN film parallel to the [111] direction of the Si(111) substrates. Scanning electron microscopy shows that the nanocolumns fabricated by PAMBE have a length of about 300-500 nm with diameters ranging from 20 to 150 nm while nanowhiskers formed by RIE have diameters of 40-80 nm and a height between 1.4 and 1.7 µm. A comparative study of the vibrational spectrum (including optical and interface phonons) of the nanostructures using conventional macro-Raman and micro-Raman scattering as well as surface-enhanced Raman scattering is presented.
authors.affiliation: Institute of Semiconductor Physics, 630090, Novosibirsk, Russia.
authors.forename: A G
authors.initials: AG
authors.lastname: Milekhin
authors.forename: R J
authors.initials: RJ
authors.lastname: Meijers
authors.forename: T
authors.initials: T
authors.lastname: Richter
authors.forename: R
authors.initials: R
authors.lastname: Calarco
authors.forename: S
authors.initials: S
authors.lastname: Montanari
authors.forename: H
authors.initials: H
authors.lastname: Lüth
authors.forename: B A
authors.initials: BA
authors.lastname: Paez Sierra
authors.forename: D R T
authors.initials: DR
authors.lastname: Zahn