Abstract
The structural properties of Er doped GaN epilayers were studied by means of extended X-ray absorption fine structure (EXAFS) measured at the Er L-III and Ga K-edges. The samples were doped with Er in-situ during growth by molecular beam epitaxy (MBE). The Ga local structure was found to be the same in all samples studied. Er L-III-edge EXAFS showed that when growth conditions were gradually changed from Ga-rich to Ga-poor, an increase in Er concentration from 0.15 at.% to 0.64 at.% is accompanied by the sequential formation of ErGaN, ErGaN clusters with locally high Er content and finally a pure ErN component. This study indicates that Er incorporation into GaN is enhanced under Ga-poor conditions, at the expense of the formation of Er-rich clusters and ErN precipitates. (c) 2005 Elsevier B.V. All rights reserved.
Original language | English |
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Pages (from-to) | 785-789 |
Number of pages | 5 |
Journal | Optical Materials |
Volume | 28 |
Issue number | 6-7 |
DOIs | |
Publication status | Published - 1 May 2006 |
Keywords
- absorption
- optical materials
- molecular beams