SELF-TRAPPING OF HOLES AND RELATED PHENOMENA IN A-SI-H

Self-trapping of holes at specific weak Si-Si bonds in a-Si:H is consi dered on the basis of an extrinsic mechanism of self-trapping suggeste d by experimental evidence. The nature of the hole wave function is el ucidated from a tight-binding approach on the basis of optically detec ted electron-nuclear double resonance experiments. Phenomena related t o self-trapping of holes and excitons are discussed.