Light-enhanced hydrogen motion ina-Si:H

Abstract
We report the first direct observation of light-enhanced hydrogen motion in hydrogenated amorphous silicon. Diffusion enhancement increases with illumination intensity in undoped material and is suppressed in doped and in compensated material. The enhancement is attributed to an increased release rate of hydrogen from silicon-hydrogen bonds in the presence of photogenerated carriers. The implications of the effect for metastable defect formation are discussed.