Spectral response of a-Si:H p-i-n solar cells degraded by blue and red light

We have degraded a-Si:H p-i-n solar cells at Voc using both red and blue light to investigate the effect of a possible different spatial distribution of defects in the intrinsic layer. We have found that the I-V and the spectral response curves of the degraded cells depend on the total density of defects only and are not sensitive to the wavelength of the degradation light. These experimental results and some peculiar features of the spectral response of the degraded cells are explained with the aid of a numerical simulation program.