Diffusion of atomic oxygen on the Si(100) surface
Issue Date
2010
Abstract
The processes of etching and diffusion of atomic oxygen on the reconstructed Si(100)-2 × - 1 surface are investigated using an embedded cluster QM/MM (Quantum Mechanics/Molecular Mechanics) method, called SIMOMM (Surface Integrated Molecular Orbital Molecular Mechanics). Hopping of an oxygen atom along the silicon dimer rows on a Si15H16 cluster embedded in an Si136H92 MM cluster model is studied using the SIMOMM/UB3LYP (unrestricted density functional theory (UDFT) with the Becke three-parameter Lee-Yang-Parr (B3LYP) hybrid functional) approach, the Hay-Wadt effective core potential, and its associated double-ζ plus polarization basis set. The relative energies at stationary points on the diffusion potential energy surface were also obtained with three coupled-cluster (CC) methods, including the canonical CC approach with singles, doubles, and noniterative quasi-perturbative triples (CCSD(T)), the canonical left-eigenstate completely renormalized (CR) analogue of CCSD(T), termed CR-CC(2,3), and the linear scaling variant of CR-CC(2,3) employing the cluster-in-molecule (CIM) local correlation ansatz, abbreviated as CIM-CR-CC(2,3). The pathway and energetics for the diffusion of oxygen from one dimer to another are presented, with the activation energy estimated to be 71.9 and 74.4 kcal/mol at the canonical CR-CC(2,3)/6-31G(d) and extrapolated, CIM-based, canonical CR-CC(2,3)/6-311G(d) levels of theory, respectively. The canonical and CIM CR-CC(2,3)/6-31G(d) barrier heights (excluding zero point vibrational energy contributions) for the etching process are both 87.3 kcal/mol. © 2010 American Chemical Society.
Source or Periodical Title
Journal of Physical Chemistry C
ISSN
1932-7447
Volume
114
Issue
29
Page
12649-12658
Document Type
Article
Language
English
Subject
Chemical structure, Silicon, Energy, Chemical calculations, Diffusion
Recommended Citation
Arora, P., Li, W., Piecuch, P., Evans, J., Albao, M., Gordon, M. (2010). Diffusion of Atomic Oxygen on the Si(100) Surface. Journal of Physical Chemistry C, 114 (29), 12649–12658. doi:10.1021/jp102998y.
Identifier
doi:10.1021/jp102998y.
Digital Copy
yes
