FDTD Optical Simulation for Organic Solar Cells Incorporated with Antireflection Nanostructures

Abstract

. To improve the performance of organic photovoltaics, we investigate an integrated device design in which the hybrid antireflection structure, composed of a surface moth-eye nanotexture and a multilayer interference film, is applied with a high-refractive-index glass substrate. The moth eye texture with a relatively long period, which is near the bandgap wavelength of organic semiconductors, is used to enhance light absorption. We perform the optical finite-difference time-domain simulation for the integrated device and find the optimal layer configuration of the multilayer interference film to maximize the photocurrent generation. In addition, we compare the absorption spectrum of the integrated device and that of the device with only moth eye coating, and show that the integrated structure is beneficial to re-alize a high level of absorption relatively uniformly as function of wavelength.