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arXiv · 1904.01857

Extended X-ray absorption fine structure study of the Er bonding in AlNO:Er x films with x $\le$ 3.6%

M. Katsikini·V. Kachkanov·Pascal Boulet·P. Edwards·Kevin Peter O'Donnell·Valerie Brien
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Abstract

The structural properties of Er-doped AlNO epilayers grown by radio frequency magnetron sputtering were studied by Extended X-ray Absorption Fine Structure (EXAFS) spectra recorded at the Er L 3 edge. The analysis revealed that Er substitutes for Al in all the studied samples and the increase in Er concentration from 0.5 to 3.6 at.% is not accompanied by formation of ErN, Er 2 O 3 or Er clusters. Simultaneously recorded X-ray Absorption Near Edge Structure (XANES) spectra verify that the bonding configuration of Er is similar in all studied samples. The Er-N distance is 2 constant at 2.18-2.19 {\AA} i.e. approximately 15% larger than the Al-N bondlength, revealing that the introduction of Er in the cation sublattice causes considerable local distortion. The Debye-Waller factor, which measures the static disorder, of the second nearest shell of Al neighbors, has a local minimum for the sample containing 1% Er that coincides with the highest photoluminescence efficiency of the sample set.

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M. Katsikini, V. Kachkanov, Pascal Boulet, P. Edwards, Kevin Peter O'Donnell, Valerie Brien. 2019-04-03. Extended X-ray absorption fine structure study of the Er bonding in AlNO:Er x films with x $\le$ 3.6%. https://doi.org/10.1063/1.5036614

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