Evidence for hydrogen motion in annealing of light-induced metastable defects in hydrogenated amorphous silicon

Abstract

The annealing of light-induced metastable defects, as measured by electron-spin resonance, exhibits a time dependence that is consistent with the kinetics of other metastable effects found in hydrogenated amorphous silicon $\ensuremath{\alpha}\ensuremath{-}\mathrm{Si}:\mathrm{H}$. The decay kinetics for these light-induced defects is related to the dispersive diffusion of hydrogen in $\ensuremath{\alpha}\ensuremath{-}\mathrm{Si}:\mathrm{H}$ providing strong support for the hypothesis that hydrogen motion is involved in the defect formation process. Mechanisms involving the motion of other defects motions, such as three- or fivefold coordinated silicon atoms, are found to be unlikely.