J. Phys. Colloques
Volume 42, Numéro C4, Octobre 1981Proceedings of the Ninth International Conference on Amorphous and Liquid Semiconductors
|Page(s)||C4-395 - C4-398|
J. Phys. Colloques 42 (1981) C4-395-C4-398
LASER-INDUCED METASTABLE STATES IN AMORPHOUS SEMICONDUCTORSM. Wautelet, R. Andrew, M. Failly-Lovato and L.D. Laude
Faculté des Sciences, Université de l'Etat, B-7000 Mons, Belgium
A model is presented in which dehybridisation of dangling bond sites is responsible for the creation , under laser irradiation , of metastable states in GD a-Si and in a-Ge. Due to strong electron-phonon coup1ing, the activation energy necessary to recover the initial state is as large as 1.5 eV in GD a-Si and points at extremely long lifetimes for such states . This model describes very well the fatigue of luminescence and metastable changes in dc conductivity which have been observed in amorphous semiconductors . It predicts a shift of the Fermi level of undoped materials after laser irradiation.