CHIH-I WUShim, H.-S.H.-S.ShimChang, J.-H.J.-H.ChangYoo, S.-J.S.-J.YooWu, C.-I.C.-I.WuKim, J.-J.J.-J.KimCHIH-I WU2018-09-102018-09-102014http://www.scopus.com/inward/record.url?eid=2-s2.0-84896467994&partnerID=MN8TOARShttp://scholars.lib.ntu.edu.tw/handle/123456789/387675We report the correlation of the electrical properties of the p-doped layer in an interconnection unit with the performance of tandem organic photovoltaic (TOPV) cells where the interconnection unit (ICU) is composed of an electron-transporting layer (ETL)/metal/p-doped hole-transporting layer (p-HTL) by systematically varying the doping concentration of the p-HTL in the ICU. The open circuit voltage is significantly increased as the doping concentration of the p-HTL increases due to the reduction of the difference between the Fermi level and the highest occupied molecular orbital level of the p-HTL. The fill factor is also enhanced with increases in the doping concentration of the p-HTL due to the enhancement of the conductivity in the p-HTL and efficient hole transport at the interface between Ag and the p-HTL through the tunneling process, rather than through the thermionic process. © 2014 the Partner Organisations.[SDGs]SDG7Electric properties; Electronic structure; Hole concentration; Open circuit voltage; Device performance; Doping concentration; Electron-transporting layers; Highest occupied molecular orbital; Hole-transporting layers; Organic photovoltaics; Organic solar cell; Thermionic process; Intensive care unitsjournal article10.1039/c3ta14628f