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Local environment of Nitrogen in GaN{y}As{1-y} epilayers on GaAs (001) studied using X-ray absorption near edge spectroscopy

J. A. Gupta·M. W. C. Dharma-wardana·A. Jürgensen·E. D. Crozier·J. J. Rehr·M. Prange
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Abstract

X-ray absorption near-edge spectroscopy (XANES) is used to study the N environment in bulk GaN and in GaN{y}As{1-y} epilayers on GaAs (001), for y \~5%. Density-functional optimized structures were used to predict XANES via multiple-scattering theory. We obtain striking agreement for pure GaN. An alloy model with nitrogen pairs on Ga accurately predicts the threshold energy, the width of the XANES ``white line'', and features above threshold, for the given X-ray polarization. The presence of N-pairs may point to a role for molecular N_2 in epitaxial growth kinetics.

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J. A. Gupta, M. W. C. Dharma-wardana, A. Jürgensen, E. D. Crozier, J. J. Rehr, M. Prange. 2004-10-20. Local environment of Nitrogen in GaN{y}As{1-y} epilayers on GaAs (001) studied using X-ray absorption near edge spectroscopy. https://doi.org/10.1016/j.ssc.2005.08.018

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