In-depth analysis of chloride treatments for thin-film CdTe solar cells

Major, J.D.; Al Turkestani, M.; Bowen, L.; Brossard, M.; Li, C.; Lagoudakis, P.; Pennycook, S.J.; Phillips, L.J.; Treharne, R.E.; Durose, K.

Abstract

CdTe thin-film solar cells are now the main industrially established alternative to silicon-based photovoltaics. These cells remain reliant on the so-called chloride activation step in order to achieve high conversion efficiencies. Here, by comparison of effective and ineffective chloride treatments, we show the main role of the chloride process to be the modification of grain boundaries through chlorine accumulation, which leads an increase in the carrier lifetime. It is also demonstrated that while improvements in fill factor and short circuit current may be achieved through use of the ineffective chlorides, or indeed simple air annealing, voltage improvement is linked directly to chlorine incorporation at the grain boundaries. This suggests that focus on improved or more controlled grain boundary treatments may provide a route to achieving higher cell voltages and thus efficiencies.

Citation

Major, J., Al Turkestani, M., Bowen, L., Brossard, M., Li, C., Lagoudakis, P., Pennycook, S., Phillips, L., Treharne, R., & Durose, K. (2016). In-depth analysis of chloride treatments for thin-film CdTe solar cells. Nature Communications, 7, Article 13231. https://doi.org/10.1038/ncomms13231

• Journal Article Type: Article
• Acceptance Date: Sep 14, 2016
• Online Publication Date: Oct 24, 2016
• Publication Date: Oct 24, 2016
• Deposit Date: Jun 27, 2018
• Publicly Available Date: Jul 17, 2018
• Journal: Nature Communications
• Publisher: Nature Research
• Peer Reviewed: Peer Reviewed
• Volume: 7
• Article Number: 13231
• DOI: https://doi.org/10.1038/ncomms13231
• Public URL: https://durham-repository.worktribe.com/output/1323323