Abstract
The local structure around In atoms in an m-plane In0.06Ga0.94N film coherently grown on a freestanding m-plane GaN substrate was investigated by polarization-dependent X-ray absorption fine-structure. A step-by-step fitting procedure was proposed for the m-plane wurtzite structure. The interatomic distance for the first nearest neighbour In - N atomic pairs was almost isotropic. For the second nearest In - Ga pairs, the interatomic distances along the m- and a-axes were longer and shorter, respectively, than that in strain-free virtual crystals as expected for the m-plane compressive strain. In contrast, the In - Ga interatomic distance in the c-direction was elongated in spite of the compressive strain, which was explained in terms of the anisotropic atomic structure on the m-plane. The local strain in the m-plane film was more relaxed than that in coherently grown c-plane single quantum wells. A few In atoms were atomically localized in all directions, and thus localized excitonic emission is expected as in the case of c-plane InGaN.The local structure around In atoms in an m-plane In0.06Ga0.94N film coherently grown on a freestanding m-plane GaN substrate was investigated by polarization-dependent XAFS measurements. A step-by-step fitting procedure was proposed for the m-plane wurtzite structure.
Original language | English |
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Pages (from-to) | 1012-1016 |
Number of pages | 5 |
Journal | Journal of Synchrotron Radiation |
Volume | 24 |
Issue number | 5 |
DOIs | |
Publication status | Published - 2017 Sep 1 |
Keywords
- InGaN
- XAFS
- local structure
- m-plane
- step-by-step fitting procedure
ASJC Scopus subject areas
- Radiation
- Nuclear and High Energy Physics
- Instrumentation