On the mechanism of potential-induced degradation in crystalline silicon solar cells

Abstract

Multicrystalline standard p-type silicon solar cells, which undergo a potential induced degradation, are investigated by different methods to reveal the cause of the degradation. Microscopic local ohmic shunts are detected by electron-beam-induced current measurements, which correlate with the sodium distribution in the nitride layer close to the Si surface imaged by time-of-flight secondary ion mass spectroscopy. The results are compatible with a model of the formation of a charge double layer on or in the nitride, which inverts the emitter