HYDROGEN STATES IN SILICON

The interactions between hydrogen and crystalline, amorphous and polyc rystalline silicon are investigated from a theoretical and computation al point of view. A comprehensive overview of various configurations i s provided. Particular attention is devoted to structures that play an important role in amorphous and polycrystalline material, such as H i nserted into Si-Si bonds, and H at dangling bonds. An examination of t he dissociation mechanism of Si-H bonds suggests an explanation for th e observed difference in stability between hydrogen and deuterium at d angling bonds. Finally, a new model to explain stretched exponential r elaxation in hydrogenated amorphous silicon is presented. (C) 1998 Els evier Science B.V. All rights reserved.