Accelerated degradation in amorphous silicon solar cells by a combination of current injection and light insolation

Influence of pin Amorphous Silicon Stack Deposition Sequence on Solar Cell Performance and Degradation

“…It was reported that the electric stress is more effective in generating defects than the light illumination. 8 It was reported that the mechanism of defect generation in electric stress is the same as that in light illumination. 9 Since the np product in the former condition is larger than that in the latter condition, the former is responsible for the high defect generation rate.…”

“…1 is associated with the recovery of the deteriorated cell, which is caused by the thermal effect from light illumination or electric stress. 8,22 Under the simultaneous electric stress and light illumination, the defect generation rate is much faster than the thermal annealing recovery rate, 8 i.e., the defect generation term in Eq. 1 is non-negligible.…”

“…It can vary with not only the stress condition but also the cell's property. 8,9 The defect generation rates of different cells can be compared from their exponent numbers. For example, the exponent number of the cell under the electric stress condition is larger than that under the light illumination condition.…”

“…For example, the exponent number of the cell under the electric stress condition is larger than that under the light illumination condition. 8 The exponential relationship between the cell deterioration and the stress time is related to the distribution of the band tail states in the p − layer. 23,24 The defect density saturates at around 10 18 −3 , which is the density of deeply localized states in the valence band tail.…”

“…4,5 The SWE in a-Si:H is dependent on the light illumination time. [6][7][8] Separately, when an a-Si:H nip cell is stressed with a forward current, its performance deteriorates. 9 It appears that the defect creation mechanism under the current stress condition is similar to that under the light illumination condition.…”