Direct observation of elemental segregation in InGaN nanowires by X-ray nanoprobe

ISSN
1862-6254
Date Issued
2011
Author(s)
Segura-Ruiz, J.
Martinez-Criado, G.
Sans, J. A.
Tucoulou, R.
Cloetens, P.
Snigireva, I.
Denker, C.
Gomez-Gomez, M. I.
Garro, N.
Cantarero, A.
DOI
10.1002/pssr.201004527
Abstract
Using synchrotron radiation nanoprobe, this work reports on the elemental distribution in single In(x)Ga(1-x)N nanowires (NWs) grown by molecular beam epitaxy directly on Si(111) substrates. Single NWs dispersed on Al covered sapphire were characterized by nano-X-ray fluorescence, Raman scattering and photoluminescence spectroscopy. Both Ga and In maps reveal an inhomogeneous axial distribution inside single NWs. The analysis of NWs from the same sample but with different dimensions suggests a decrease of In segregation with the reduction of NW diameter, while Ga distribution seems to remain unaltered. Photoluminescence and Raman scattering measurements carried out on ensembles of NWs exhibit relevant signatures of the compositional disorder. (C) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim