Real-time observation of light-induced macroscopic changes in thin film solar cells: Device degradation mechanism

Abstract

Hydrogenated polymorphous silicon (pm-Si:H) is a material consisting of a small volume fraction of nanocrystals embedded in an amorphous matrix. pm-Si:H solar cells demonstrate interesting initial degradation behaviors such as rapid initial change in photovoltaic parameters and large macroscopic structural change during light-soaking. The precise dynamics of the light-induced degradation was studied in a series of light-soaking experiments. Complementary studies reveal that the initial degradation of pm-Si:H solar cells originate from the modification of silicon-hydrogen bonding on the surface of silicon nanocrystals in pm-Si:H.