Performance and stability improvement of single junction a-Si:H solar cell by interface engineering

In this study, the influence of p/i interface on the stability of amorphous silicon solar cells has been investigated by light-induced degradation study. To peruse this study a series of p-i-n solar cells with and without p/i interface buffer layer have been fabricated using plasma enhanced chemical vapor deposition (PECVD) technique. In the light soaking experiment, the samples were kept under one sun illumination for 1000 h. The degradation results reveal that the stability of the solar cell with buffer layer at p/i interface has significantly improved. It has been found that the solar cell with p/i buffer layer has only 13.42% degradation in power conversion efficiency after 1000 h light soaking. Whereas the cell without any interface treatment, the degradation in efficiency has reached 23.56%. The quantum efficiency and dark current measurement were also performed to establish the correlation between interface degradation and stability of the a-Si:H solar cells. Our extensive light soaking studies indicate that the light-induced degradation in a-Si:H solar cell is not only a bulk or material degradation effect. The p/i interface deterioration also has a major influence on the instability of the cell. Based on this hypothesis, a solar cell designed through proper device engineering has shown improved performance and stability against light soaking.