Theoretical study of strain fields and local order in hydrogenated amorphous silicon

This paper presents the results of a tight-binding molecular-dynamics simulation which demonstrates that the local order and intrinsic stress in hydrogenated amorphous silicon are influenced by the hydrogen concentration. Snapshots of the atomic-level stresses in the simulated structures show that amorphous silicon exhibits a broad distribution in the magnitude of the local stress, rather than a uniform stress field over the whole simulated structure. The corresponding spatial and temporal correlations of the stress fields are interpreted to provide information on the effects of hydrogen on the short- and medium-range order.