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Quantitative study of molecular N_2 trapped in disordered GaN:O films

B. J. Ruck·A. Koo·U. D. Lanke·F. Budde·S. Granville·H. J. Trodahl·A. Bittar·J. B. Metson·V. J. Kennedy·A. Markwitz
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Abstract

The structure of disordered GaN:O films grown by ion-assisted deposition is investigated using x-ray absorption near-edge spectroscopy and Raman spectroscopy. It is found that between 4 and 21 % of the nitrogen in the films is in the form of molecular N_2 that interacts only weakly with the surrounding matrix. The anion to cation ratio in the GaN:O host remains close to unity, and there is a close correlation between the N_2 fraction, the level of oxygen impurities, and the absence of short-range order in the GaN:O matrix.

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B. J. Ruck, A. Koo, U. D. Lanke, F. Budde, S. Granville, H. J. Trodahl, A. Bittar, J. B. Metson, V. J. Kennedy, A. Markwitz. 2004-08-09. Quantitative study of molecular N_2 trapped in disordered GaN:O films. https://doi.org/10.1103/physrevb.70.235202

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