Finite Element Numeric Simulation of Organic Solar Cells with Gold Thin Film

Abstract

In this paper, we have explored the potential of organic solar cells with gold layers, simulating different geometries and comparing them with the experimental data obtained from the devices produced at the “optoelectronic organic devices laboratory at Ben Gurion University of the Negev, Israel.” Thin-film heterojunction solar devices are analyzed using a basic chemical technology of GLASS/ITO/PEDOT,PSS/P3HT, PCBM, and another type of nanostructure where the gold layer is added. A standard device is realized on top of a transparent substrate such as glass or flexible polymer Polyethylene Terephthalate (PET). The first layer is the anode, which is made of conductive material and is also transparent. In our case, the very common material Indium-Tin-Oxide (ITO) is used. To facilitate the transition between the active layer and the anode, an intermediate layer is introduced. Hole Transport Layer (HTL) 's high hole mobility allows holes to move towards the anode instead of the cathode. On top of these layers the organic active layer is constituted by a blend of two organic materials configuring a multiple junction morphology (Bulk Heterojunction or BHJ). In our case, two commonly organic materials [6,6]-Phenyl C61 Butyric acid Methyl ester and Poly(3-Hexylthiophene-2,5-diyl) (PCBM:P3HT) are used. The cathode on top organic active layer is made of highly conductive opaque metal, mostly Aluminum (Al). The finite-element method has been used to compute the electromagnetic field distributions. The results show that the model with the gold layer increases the electrical performance of organic solar cells.