The annealing behavior of epitaxial n+p solar cells was characterized by using various techniques. Current-voltage measurements were performed under simulated solar illumination, or in the dark. The radiation-induced defect spectra were monitored by using deep-level transient spectroscopy. The irradiated cells were annealed at temperatures that ranged from 300 to 500K. Some cells were annealed while under illumination, and short-circuited, while others were annealed in the dark. It was found that the results were independent of the presence of illumination and of the nature of the bombarding particle. An annealing stage was detected, at temperatures of between 400 and 500K, within which the radiation-induced defects, H3 and H4, were removed. However, most of the radiation-induced defects did not anneal out.

R.J.Walters, S.R.Messenger, H.L.Cotal, G.P.Summers: Journal of Applied Physics, 1996, 80[8], 4315-21