Luminescence and recombination in hydrogenated amorphous silicon

Abstract Luminescence and related investigations of recombination in hydrogenated amorphous silicon prepared by glow discharge and sputtering are described. Emphasis is given to a detailed discussion of the various competing radiative and non-radiative recombination mechanisms. The evidence of the luminescence data is compared to other measurements that involve recombination processes. The experiments demonstrate that the dominant luminescence is a tunnelling transition between band tail electrons and holes. Other luminescence transitions involving defects and impurities, and the role of phonon interactions in the transition are discussed. Experiments in which luminescence is used as a probe of the properties of a-Si:H and related materials are also discussed.