New dielectric/metal/dielectric electrode for organic photovoltaic cells using Cu:Al alloy as metal

摘要

Given the rapidly increasing demand for flexible and inexpensive optoelectronic devices, it is necessary to find a substitute for ITO (Indium Tin Oxide). Among the considered alternatives, we have chosen in the present work Dielectric/Metal/Dielectric (D/M/D) trilayer structures deposited under vacuum. In these D/ M/D structures, when Ag is the metal, highly performing and stable Transparent Conductive Electrodes (TCEs) are obtained. When Ag is replaced by Cu, which is far less expensive, results are not similar due to the tendency of Cu to diffuse into the transition metal oxides. Therefore we improve the stability of the new TCEs by using the Cu alloy Cu:Ag in ZnS/M/WO3 structures. The best results were obtained when M = Cu:Ag (16 nm)/Ag (1 nm). Flexible and quite stable TCEs were obtained.