Atomic-resolution three-dimensional imaging of germanium self-interstitials near a surface: Aberration-corrected transmission electron microscopy
Atomic-resolution three-dimensional imaging of germanium self-interstitials near a surface: Aberration-corrected transmission electron microscopy
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DOI：
10.1103/physrevb.80.014114
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发表时间：
2009-07
影响因子：
3.7
通讯作者：
D. Alloyeau;B. Freitag;S. Dag;Lin Wang;C. Kisielowski
中科院分区：
文献类型：
--
作者：
D. Alloyeau;B. Freitag;S. Dag;Lin Wang;C. Kisielowski
Received 10 April 2009; revised manuscript received 27 May 2009; published 27 July 2009 We report the formation and direct observation of self-interstitials in surface proximity of an elemental semiconductor by exploiting subthreshold effects in a new generation of aberration-corrected transmission electron microscopes. We find that the germanium interstitial atoms reside close to hexagonal, tetragonal, and S-interstitial sites. Using phase-contrast microscopy, we demonstrate that the three-dimensional position of interstitial atoms can be determined from contrast analysis, with subnanometer precision along the electronbeam direction. Comparison with a first-principles study suggests a strong influence of the surface proximity or a positively charged interstitial. More generally, our investigation demonstrates that imaging of single atom can now be utilized to directly visualize single-defect formation and migration. These high-resolution electron microscopy studies are applicable to a wide range of materials since the reported noise level of the images even allows the detection of single-light atoms.
