Stability of polymer solar cells: Dependence on working pressure

• Published in: Solar energy materials and solar cells Vol. 111; pp. 212 - 215
• Main Authors: Roesch, Roland, Seeland, Marco, Bärenklau, Maik, Gobsch, Gerhard, Hoppe, Harald
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.04.2013; Elsevier
• Subjects: Applied sciences; Degradation; Devices; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrodes; Energy; Evaporation; Exact sciences and technology; Impurity; Natural energy; Operation. Load control. Reliability; Photovoltaic cells; Photovoltaic conversion; Physical vapor deposition; Polymer solar cell; Power networks and lines; Pressure; Solar cells; Solar cells. Photoelectrochemical cells; Solar energy; Stability; Degradation; Stability; Impurity; Polymer solar cell; Pressure; Performance evaluation; Profitability; Power system economics; Organic solar cells; Burn in test; Trade; Physical vapor deposition; Fullerenes; Irradiation; Power markets; Damaging
• ISSN: 0927-0248; 1879-3398
• DOI: 10.1016/j.solmat.2012.12.020

We investigated the degradation behavior of polymer/fullerene solar cells processed at different working pressures during the deposition of the metal back electrode by physical vapor deposition (PVD). The temporal development of the photovoltaic parameters was determined with a homemade automated degradation setup for constant irradiation of ∼1000W/m2 in air. The initial device efficiency improved with evacuation time. The device stability itself depended also on the PVD working pressure: the larger the PVD pressure, the more pronounced was the fast decay of the performance. As reactive remnants, still present within the evaporation chamber due to the larger PVD working pressure, seemed to contribute to the so-called device “burn-in”, yielding overall stronger decays for larger PVD working pressures. As a consequence a trade-off between final base working pressure and pumping time seems to be a requirement for cost-effective industrial evaporation processes. ► Performance investigation of polymer solar cells as a function of PVD working pressure. ► Influence of oxygen content in active layer on device stability: stronger burn-in. ► Initial solar cell performance almost independent of PVD working pressure.