Inverted Organic Solar Cells Fabricated with Room‐Temperature‐deposited Transparent Multilayer Electrodes

Abstract

We investigated the electrical, optical, and structural properties of Al‐doped ZnO ( AZO )/Ag/ AZO and indium gallium zinc oxide ( IGZO )/Ag/ IGZO multilayer films, and the performance of inverted organic solar cells ( OSCs ) fabricated with Sn‐doped indium oxide ( ITO ), AZO /Ag/ AZO , and IGZO /Ag/ IGZO electrodes. Even though deposited at room temperature, AZO /Ag/ AZO (36 nm/19 nm/36 nm) and IGZO /Ag/ IGZO (39 nm/19 nm/39 nm) multilayer films showed sheet resistances of 4.1 and 4.2 Ω/sq, resistivities of 3.3 × 10 −5 and 4.1 × 10 −5 Ω cm, and transmittances of 93 and 88% at 550 nm, respectively. Figures of merit ( FOMs ) were obtained to be 99.9 and 49.9 × 10 −3 Ω −1 for the AZO /Ag/ AZO and IGZO /Ag/ IGZO films, respectively. Inverted OSCs fabricated using the as‐deposited AZO /Ag/ AZO and IGZO /Ag/ IGZO electrodes produced power conversion efficiencies ( PCEs ) of 2.4 and 2.6%, respectively, while that with high‐temperature annealed ITO electrode gave a PCE of 3.2%.