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arXiv · 1403.6306

Negative-U properties for substitutional Au in Si

Fabiano Corsetti·Arash A. Mostofi
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Abstract

The isolated substitutional gold impurity in bulk silicon is studied in detail using electronic structure calculations based on density-functional theory. The defect system is found to be a non-spin-polarized negative-U centre, thus providing a simple solution to the long-standing debate over the electron paramagnetic resonance signal for gold in silicon. There is an excellent agreement (within 0.03 eV) between the well-established experimental donor and acceptor levels and the predicted stable charge state transition levels, allowing for the unambiguous assignment of the two experimental levels to the (1+/1-) and (1-/3-) transitions, respectively, in contrast to previously held assumptions about the system.

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Fabiano Corsetti, Arash A. Mostofi. 2014-03-25. Negative-U properties for substitutional Au in Si. https://doi.org/10.1209/0295-5075%2F105%2F57006

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