Effect of the active-layer thickness on the short-circuit current analyzed using the generalized transfer matrix method

The effect of the active-layer thickness on the short-circuit current of organic solar cells (OSCs) was numerically investigated using a new optical modeling approach, the generalized transfer matrix method, where the optical interaction of an incoherent glass substrate with coherent layers is analyzed with simple matrix forms. The effect of the optical-spacer thickness on the spatial distribution of the electric-field intensity, time-averaged Poynting vector, and absorptivity was calculated. By incorporating the spectral absorptance with the solar irradiance, the short-circuit current was obtained at various thicknesses of the poly(3-hexylthiophene):phenyl-C61-butyric acid methyl ester (P3HT:PCBM) active layer to show how the variation of the P3HT:PCBM active-layer thickness affects the performance of the OSC.