Hole trapping at hydrogenic defects in amorphous silicon dioxide

We used ab initio calculations to investigate the hole trapping reactions at a neutral defect generated in amorphous silicon dioxide networks by the interaction of strained Si-O bonds with atomic hydrogen, a so-called hydroxyl E' center. It was found that the hole trapping at this defect leads to two distinct charged configurations. The first one consists of an H atom bound to a bridging O in a hydronium-like configuration. The second configuration involves relaxation of a Si atom through the plane of its oxygen neighbors facilitated by a weak interaction with a 2-coordinated O atom. The distribution of total energy differences between these two configurations calculated for a number of amorphous network models has a width of about 1.0 eV. These hole trapping reactions are discussed in the context of Si complementary metal-oxide-semiconductor device reliability issues. (C) 2015 Elsevier B.V. All rights reserved.