Hydrogen collision model of light-induced metastability in hydrogenated amorphous silicon

A new model of light-induced metastability (Staebler-Wronski effect) in hydrogenated amorphous silicon is proposed. When two mobile H atoms generated by photo-induced carriers collide, they form a metastable, immobile complex containing two Si-H bonds. Excess metastable dangling bonds remain at the uncorrelated sites from which the colliding H were excited. The model accounts quantitatively for the kinetics of light-induced defect creation, both near room temperature and at 4.2 K. Other experimental results, including light-induced and thermal annealing kinetics, are also explained. (C) 1998 Elsevier Science Ltd.