EVIDENCE FOR PROTON MOTION IN THE RECOVERY OF LIGHT-INDUCED DEGRADATION IN AMORPHOUS-SILICON SOLAR-CELLS

The light-induced degradation of amorphous silicon solar cells can be reversed by: the application of a strong electric field in the dark, a nd the rate of reversal increases with field strength, temperature, an d light intensity. The activation energy for annealing the degradation in the dark is reduced from about 1.34 eV under open circuit conditio ns to 1.16 eV by applying a strong reverse bias. When the degraded cel ls are exposed to intense illumination in addition to a strong reverse bias, the activation energy for the recovery of the performance decre ases to about 0.77 eV. Both the light-induced degradation and the reve rsal of the degradation can be explained by a model based on proton mo tion within a metastable defect complex. (C) 1998 American Institute o f Physics.[S0021-8979(98)04203-0].