Anatase TiO2 and ITO co-sputtered films for an indium-saving multicomponent electrode in organic solar cells

Abstract

We report the characteristics of a Ti-In-Sn-O (Ti-ITO) multicomponent electrode prepared by co-sputtering of ITO and anatase TiO2 targets for reducing high-cost indium content in the anode layer of organic solar cells (OSCs). The dependence of electrical, optical, structural, and surface properties of the Ti-ITO multicomponent electrodes on the RF power was investigated in detail. The optimized Ti-ITO (80W TiO2 co-sputtered ITO) electrode exhibited a low sheet resistance of 18.06 Omega/square, a high average optical transmittance of 80.61% and a root mean square roughness of 2.40 nm. The anatase TiO2 phase in the ITO matrix prevents the bixbyite structure from attaining the preferred orientation, producing a smooth surface of the Ti-ITO electrode. Moreover, the OSC with the optimized Ti-ITO anode showed an open circuit voltage (0.60 V), short circuit current (8.33 mA/cm(2)), fill factor (63.99%) and power conversion efficiency (3.18%) comparable to those of OSCs with a reference ITO electrode. This indicates that the Ti-ITO multicomponent electrode is a promising indium-saving multicomponent electrode that to reduces the indium content in ITO electrodes for low-cost OSCs. (C) 2011 Elsevier B.V. All rights reserved.