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Title: Mechanism of oxidation protection of the Si(001) surface by sub-monolayer Sr template

Abstract

We investigate theoretically the oxidation stability of the Si(001) (2 × 1) reconstructed surface passivated by Sr. Using density functional theory, we find that the Sr surface with ½ monolayer of Sr is protected against oxidation. The presence of Sr delays the oxidation of the surface dimer, and even when the dimer is oxidized, O does not react with the back-bond, preventing the unwanted vertical growth of SiO{sub 2}. We also show that ¼ monolayer of Sr protects the Si surface in a different way. In the presence of ¼ monolayer of Sr, O atoms are attracted to the Sr-Si dimer complexes, thus preventing the formation of SiO{sub 2}.

Authors:
; ;  [1]
  1. Department of Physics, The University of Texas at Austin, Austin, Texas 78712 (United States)
Publication Date:
OSTI Identifier:
22597673
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 120; Journal Issue: 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ATOMS; DENSITY; DENSITY FUNCTIONAL METHOD; DIMERS; OXIDATION; SILICA; SILICON OXIDES; STRONTIUM; SURFACES

Citation Formats

Fredrickson, Kurt D., Seo, Hosung, and Demkov, Alexander A., E-mail: demkov@physics.utexas.edu. Mechanism of oxidation protection of the Si(001) surface by sub-monolayer Sr template. United States: N. p., 2016. Web. doi:10.1063/1.4960575.
Fredrickson, Kurt D., Seo, Hosung, & Demkov, Alexander A., E-mail: demkov@physics.utexas.edu. Mechanism of oxidation protection of the Si(001) surface by sub-monolayer Sr template. United States. doi:10.1063/1.4960575.
Fredrickson, Kurt D., Seo, Hosung, and Demkov, Alexander A., E-mail: demkov@physics.utexas.edu. 2016. "Mechanism of oxidation protection of the Si(001) surface by sub-monolayer Sr template". United States. doi:10.1063/1.4960575.
@article{osti_22597673,
title = {Mechanism of oxidation protection of the Si(001) surface by sub-monolayer Sr template},
author = {Fredrickson, Kurt D. and Seo, Hosung and Demkov, Alexander A., E-mail: demkov@physics.utexas.edu},
abstractNote = {We investigate theoretically the oxidation stability of the Si(001) (2 × 1) reconstructed surface passivated by Sr. Using density functional theory, we find that the Sr surface with ½ monolayer of Sr is protected against oxidation. The presence of Sr delays the oxidation of the surface dimer, and even when the dimer is oxidized, O does not react with the back-bond, preventing the unwanted vertical growth of SiO{sub 2}. We also show that ¼ monolayer of Sr protects the Si surface in a different way. In the presence of ¼ monolayer of Sr, O atoms are attracted to the Sr-Si dimer complexes, thus preventing the formation of SiO{sub 2}.},
doi = {10.1063/1.4960575},
journal = {Journal of Applied Physics},
number = 6,
volume = 120,
place = {United States},
year = 2016,
month = 8
}
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