The arrangement of B~atoms in a doped Si(111)-(3×3)R30∘:B system was studied using near-edge x-ray absorption fine structure (NEXAFS). Boron atoms were deposited via segregation from the bulk by flashing the sample repeatedly. The positions of B~atoms are determined by comparing measured polarized (angle-dependent) NEXAFS spectra with spectra calculated for various structural models based on ab-initio total energy calculations. It is found that most of boron atoms are located in sub-surface L1c positions, beneath a Si atom. However, depending on the preparation method a significant portion of B~atoms may be located elsewhere. A possible location of these non-L1c-atoms is at the surface, next to those Si atoms which form the (3×3)R30∘ reconstruction.
@article{arxiv.1902.06244,
title = {Local geometry around B atoms in B/Si(111) from polarized x-ray absorption spectroscopy},
author = {Saleem Ayaz Khan and Martin Vondráček and Peter Blaha and Kateřina Horáková and Jan Minár and Ondřej Šipr and Vladimír Cháb},
journal= {arXiv preprint arXiv:1902.06244},
year = {2019}
}