Effect of Deposition Sequence in MoO3 and HAT-CN Dual-anode Buffer Layer on Inverted Organic Photovoltaics

초록

Interface engineering plays a critical role in the device performance of organic photovoltaics (OPVs). In inverted OPVs, the top anode must have a high work function to match the highest occupied molecular orbital level of a p-type organic semiconductor. Therefore, a functional interlayer with a high work function is inserted between the light-absorbing layer and anode. OPVs with a dual-anode buffer layer have been reported to exhibit a superior performance than those with a single-anode buffer layer. Herein, the device performance of inverted OPVs with a poly(3-hexylthiophene-2,5-diyl):[6,6]-phenyl-C₆₁-butyric acid methyl ester light-absorbing layer and dual-anode buffer layer of MoO₃ and 1,4,5,8,9,11-hexaazatriphenylenehexacarbonitrile (HAT-CN) is investigated. The power conversion efficiency (PCE) of the OPV with the HAT-CN/MoO₃/Al anode system is lower than that with the conventional MoO3/Al anode system. However, the PCE of the OPV with MoO₃/HAT-CN/Al is slightly higher than that with MoO₃/Al. The change in the device performance by varying the deposition sequence of HAT-CN and MoO₃ is discussed based on the built-in potential. © The Korean Vacuum Society.

키워드