Open this publication in new window or tab >>2011 (English)Licentiate thesis, comprehensive summary (Other academic)
Abstract [en]
This Licentiate Thesis covers experimental and theoretical investigations of the bulk plasmon response to different compositions and strain states of group III-nitride materials. Investigated materials were grown using magnetron sputtering epitaxy and metal organic chemical vapour deposition and studied by Rutherford backscattering spectrometry, X-ray diffraction, electron microscopy and electron energy loss spectroscopy (EELS).
It is shown that low-loss EELS is a powerful method for a fast compositional determination in AlxIn1-xN system. The bulk plasmon energy of the investigated material system follows a linear relation with respect to lattice parameter and composition in unstrained layers.
Furthermore, the effect of strain on the bulk plasmon peak position has been investigated by using low-loss EELS in group III-nitrides. We experimentally determine the AlN bulk plasmon peak shift of 0.156 eV per 1% volume change. The AlN peak shift was corroborated by full potential calculations (Wein2k), which reveal that the bulk plasmon peak position of III-nitrides varies near linearly with unit cell volume variations.
Finally, self-assembled ternary Al1-xInxN nanorod arrays with variable In concentration have been realized onto c-plane sapphire substrates by ultra-high-vacuum magnetron sputtering epitaxy with Ti0.21Zr0.79N or VN seed layer assistance. The nanorods exhibit hexagonal cross-sections with preferential growth along the Al1-xInxN c-axis. A coaxial rod structure with higher In concentration in the core was observed by scanning transmission electron microscopy in combination with low-loss EELS.
Place, publisher, year, edition, pages
Linköping: Linköping University Electronic Press, 2011. p. 47
Series
Linköping Studies in Science and Technology. Thesis, ISSN 0280-7971 ; 1487
National Category
Natural Sciences
Identifiers
urn:nbn:se:liu:diva-67985 (URN)LIU-TEK-LIC-2011:26 (Local ID)978-91-7393-161-8 (ISBN)LIU-TEK-LIC-2011:26 (Archive number)LIU-TEK-LIC-2011:26 (OAI)
Presentation
2011-06-01, Planck, Fysikhuset, Campus Valla, Linköpings universitet, Linköping, 10:15 (English)
Opponent
Supervisors
2011-05-042011-05-042023-02-08Bibliographically approved