Hydrogen bonding and migration in amorphous silicon
Istituto Nazionale per la Fisica della Materia,
Dipartimento di Fisica, Università di Milano - Via Celoria 16, 20133 Milano, Italy
Accepted: 19 September 1996
We present a theoretical study on the structure of hydrogenated amorphous silicon based on large-scale tight-binding molecular-dynamics simulations. The atomistic model here discussed is consistent with experimental findings and allows for a complete characterization of Si-H complexes embedded in the amorphous network. We also investigate the mechanism of migration of hydrogen in two concentration regimes and compute the activation energy for such a process. The microscopic mechanism emerging from the present investigation gives rise to a diffusion behaviour consistent with experimental results.
PACS: 66.30.Jt – Diffusion, migration, and displacement of impurities / 61.72.Ji – Point defects (vacancies, interstitials, color centers, etc.) and defect clusters / 61.43.Dq – Amorphous semiconductors and metals
© EDP Sciences, 1996