Hydrogen-Induced Rupture of Strained Si─O Bonds in Amorphous Silicon Dioxide

Using ab initio modeling we demonstrate that H atoms can break strained Si{O bonds in continuous amorphous (a)-SiO2 networks, resulting in a defect consisting of a 3-coordinated Si atom with an unpaired electron facing a hydroxyl group, adding to the density of dangling bond defects, such as E0 centres. The 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 signifcant implications for our understanding of processes in nano-scaled silica, e.g., in porous low-permittivity insulators, and strained variants of a-SiO2. ispartof: Physical Review Letters vol:114 issue:11 pages:1-5 ispartof: location:United States status: published