Recent experimental studies have shown that well-annealed, unstrained Si(105) surfaces appear disordered and atomically rough when imaged using scanning tunnelling microscopy (STM). We construct new models for the Si(105) surface that are based on single- and double-height steps separated by Si(001) terraces, and propose that the observed surface disorder of Si(105) originates from the presence of several structural models with different atomic-scale features but similar energies. This degeneracy can be removed by applying compressive strains, a result that is consistent with recent observations of the structure of the Ge/Si(105) surface.
@article{arxiv.cond-mat/0306547,
title = {Structure and stability of the Si(105) surface},
author = {C. V. Ciobanu and V. B. Shenoy and C. Z. Wang and K. M. Ho},
journal= {arXiv preprint arXiv:cond-mat/0306547},
year = {2009}
}