Stabilization of amorphous GaN by oxygen

F. Budde; B. J. Ruck; A. Koo; S. Granville; H. J. Trodahl; A. Bittar; G. V. M. Williams; M. J. Ariza; B. Bonnet; D. J. Jones; J. B. Metson; S. Rubanov; P. Munroe

doi:10.1063/1.2014937

arXiv · cond-mat/0407659

Stabilization of amorphous GaN by oxygen

F. Budde·B. J. Ruck·A. Koo·S. Granville·H. J. Trodahl·A. Bittar·G. V. M. Williams·M. J. Ariza·B. Bonnet·D. J. Jones·J. B. Metson·S. Rubanov·P. Munroe

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Abstract

Ion assisted deposition (IAD) has been investigated for the growth of GaN, and the resulting films studied by x-ray diffraction and absorption spectroscopy and by transmission electron microscopy. IAD grown stoichiometric GaN consists of random-stacked quasicrystals of some 3 nm diameter. Amorphous material is formed only by incorporation of 15% or more oxygen, which we attribute to the presence of non-tetrahedral bonds centered on oxygen. The ionic favourability of heteropolar bonds and its strikingly simple constraint to even-membered rings is the likely cause of the instability of stoichiometric a-GaN.

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F. Budde, B. J. Ruck, A. Koo, S. Granville, H. J. Trodahl, A. Bittar, G. V. M. Williams, M. J. Ariza, B. Bonnet, D. J. Jones, J. B. Metson, S. Rubanov, P. Munroe. 2004-07-26. Stabilization of amorphous GaN by oxygen. https://doi.org/10.1063/1.2014937

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