Proceedings of the 9th International Conference on X-Ray Absorption Fine Structure

J. Phys. IV France 7 (1997) C2-1127-C2-1128
DOI: 10.1051/jp4:19972156

N- and Al-K-Edge EXAFS of AIN Grown on GaAs by MBE

M. Katsikini^{1, 2}, E.C. Paloura^{2, 3}, E. Holub-Krappe², T.S. Cheng⁴ and C.T. Foxon<sup>4

1</sup>  Aristotle University of Thessaloniki, Department of Physics, 54006 Thessaloniki, Greece
²  Hahn-Meitner Institute (A.S.), Glienicker Str. 100, 14109 Berlin, Germany
³  Aristotle University of Thessaloniki, Department of Physics 54006 Thessaloniki, Greece
⁴  University of Nottingham, Department of Physics, NG7 2RD UK

Abstract
Hexagonal AIN, epitaxially grown on GaAs, is studied with X-ray absorption measurements at the N-and Al-K-edges. The measured nearest neighbour (nn) distances are found shorter than expected by 0.04Å to 0.13Å for the 1^st to 3^rd nn shells, respectively, while there is no evidence of undercoordination for the N or Al atoms. The reduction in the nn distances is attributed to the presence of oxygen contamination. The characteristic angular dependence of the N-K-edge NEXAFS spectra verifies the hexagonal structure of the AIN film while the N-AI-N bond angle, determined from the angular dependence of the NEXAFS spectra, is found equal to 53.8±5.7° indicating that the oxygen does not distort significantly the local symmetry around the N atom.

© EDP Sciences 1997