title: Hydrogen-induced rupture of strained Si─O bonds in amorphous silicon dioxide.
abstract: Using ab initio modeling we demonstrate that H atoms can break strained Si─O bonds in continuous amorphous silicon dioxide (a-SiO(2)) networks, resulting in a new defect consisting of a threefold-coordinated Si atom with an unpaired electron facing a hydroxyl group, adding to the density of dangling bond defects, such as E' centers. The energy barriers to form this defect from interstitial H atoms range between 0.5 and 1.3 eV. This discovery of unexpected reactivity of atomic hydrogen may have significant implications for our understanding of processes in silica glass and nanoscaled silica, e.g., in porous low-permittivity insulators, and strained variants of a-SiO(2).
authors.affiliation: Department of Physics and Astronomy and London Centre for Nanotechnology, University College London, Gower Street, London WC1E 6BT, United Kingdom.
authors.forename: Al-Moatasem
authors.initials: AM
authors.lastname: El-Sayed
authors.affiliation: Department of Physics and Astronomy and London Centre for Nanotechnology, University College London, Gower Street, London WC1E 6BT, United Kingdom.
authors.forename: Matthew B
authors.initials: MB
authors.lastname: Watkins
authors.affiliation: Institute for Microelectronics, Technische Universität Wien, A-1040 Vienna, Austria.
authors.forename: Tibor
authors.initials: T
authors.lastname: Grasser
authors.affiliation: Department of Physics, University of Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium.
authors.forename: Valery V
authors.initials: VV
authors.lastname: Afanas'ev
authors.affiliation: Department of Physics and Astronomy and London Centre for Nanotechnology, University College London, Gower Street, London WC1E 6BT, United Kingdom.
authors.forename: Alexander L
authors.initials: AL
authors.lastname: Shluger