ANM
2010
3rd
International Conference on Advanced Nano Materials
12-15 September 2010 - Agadir, Morocco
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Abstract
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ANMM286 |
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OPTICAL CHARACTERIZATION OF INN AND INGAN NANOWIRES FOR
ENERGY APPLICATIONS |
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N. Garro, M.
Gómez-Gómez, J. A. Segura-Ruiz, A. Frau, A. Cantarero, C.
Denker, J. Malindretos, A. Rizzi |
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a Institut de Ciència dels Materials,
Universitat de València, E-46071 Valencia, Spain
b IV. Physikalisches Institut, Georg-August Universitaet
Göttingen, Germany |
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The
energy band gap of the InxGa1-xN alloy could be potentially tuned
between those of the two binary compounds over a wide energy range from
the near IR to the near UV region. Such degree of freedom along
with its radiation resistance locates InxGa1-xN as the most suitable
material for high-efficiency multijunction solar cells. However,
the limited miscibility of In induces composition inhomogeneities
and a strong drop-off in the optical efficiency for high indium
concentration. It has been pointed out that nanocolumnar
morphologies favour strain relaxation and full composition tunability
of InxGa1–xN nanowires (with x = 0 to 1) has recently been
demonstrated. While InN and GaN nanowires have been successfully grown
by several means, ternary nanowires are still rather unexplored.
The aim of this work was achieving InxGa1-xN nanowires with a
controlled In composition. The morphology and
composition of ensembles of InxGa1-xN nanowires grown by molecular beam
epitaxy on bare Si (111) under different conditions have been
investigated by means of SEM, photoluminescence, Raman scattering, and
XR-fluorescence. According to the overall results, ternary
nanowires with a good morphology and a reasonable tunability could be
achieved. Single nanowires were also investigated by optical means.
Photoluminescence spectra revealed the existence of In-rich zones even
within a single nanowire. The nanowire surfaces were functionalised
with Au nanoparticles in order to enhance the Raman scattering signal
of individual wires.
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