PHOTOINDUCED EFFECTS AND METASTABILITY IN AMORPHOUS-SEMICONDUCTORS AND INSULATORS

Amorphous semiconductors, being intrinsically metastable in nature, ex hibit a wide variety of changes in their physical properties, particul arly when photoinduced using bandgap illumination. This article review s the photoinduced phenomena exhibited by amorphous semiconductors suc h as amorphous hydrogenated silicon (and other tetrahedrally coordinat ed materials) and chalcogenide glasses. Features exhibited in common b y all types of amorphous semiconductors, whether in the experimentally observed photoinduced metastability or the theoretical models used to account for such behaviour, are stressed.