J. Phys. IV France 7 (1997) C2-1129-C2-1130
Angle Resolved NEXAFS Spectra of Hexagonal and Cubic GaNM. Katsikini1, 2, E.C. Paloura2, 3, T.S. Cheng4 and C.T. Foxon4
1 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
Phase stabilised cubic and hexagonal GaN thin films, grown by MBE, are studied using angle (φ) resolved NEXAFS measurements at the N-K-edge. It is demonstrated that the energy positions and intensities of the characteristic NEXAFS resonances depend on the crystal symmetry and can be used as a fingerprint of the symmetry of the examined crystal. Deviations from the cubic or hexagonal symmetries are clearly detectable since they lead to a shift in the resonances of the NEXAFS structure and a characteristic intensity angular dependence. Based on the above results, a formalization for a quantitative assessment of the cubic and hexagonal contributions in a mixed crystal is discussed.
© EDP Sciences 1997