RT info:eu-repo/semantics/article
T1 Spectrally and spatially resolved cathodoluminescence of undoped/Mg-doped GaN core-shell nanowires: a local probe into activation of Mg acceptors in non-polar and semi-polar crystal faces
A1 Hortelano Santos, Vanesa
A1 Martínez Sacristán, Óscar
A1 Artús, L.
A1 Cuscó, R.
A1 Jiménez López, Juan Ignacio
K1 Cathodoluminescence
AB Spectrally and spatially resolved cathodoluminescence (CL) measurements were carried out at 80 K on undoped/Mg-doped GaN core-shell nanowires grown by selective area growth metalorganic vapor phase epitaxy in order to investigate locally the optical activity of the Mg dopants. A study of the luminescence emission distribution over the different regions of the nanowires is presented. We have investigated the CL fingerprints of the Mg incorporation into the non-polar lateral prismatic facets and the semi-polar facets of the pyramidal tips. The amount of Mg incorporation/activation was varied by using several Mg/Ga flow ratios and post-growth annealing treatments. For lower Mg/Ga flow ratios, the annealed nanowires clearly display a donor-acceptor pair band emission peaking at 3.26-3.27 eV and up to 4 LO phonon replicas, which can be considered as a reliable indicator of effective p-type Mg doping in the nanowire shell. For higher Mg/Ga flow ratios, a substantial enhancement of the yellow luminescence emission as well as several emission subbands are observed, which suggests an increase of disorder and the presence of defects as a consequence of the excess Mg doping,
PB IOP Publishing
SN 0957-4484
YR 2016
FD 2016
LK http://uvadoc.uva.es/handle/10324/21760
UL http://uvadoc.uva.es/handle/10324/21760
LA eng
NO Nanotechnology, 2016, 27(9), p. 095706
NO Producción Científica
DS UVaDOC
RD 24-nov-2024