A Comparative Study of the VOC in CuPc and SubPc Organic Solar Cells

The open-circuit voltage (V-OC) with respect to the reverse dark saturation current density in planar CuPc/C-60 and non-planar boron subphthalocyanine chloride (SubPc)/C-60 organic solar cell (OSCs) devices is compared in the present study. The fabricated OSCs devices were: ITO/CuPc/C-60/BCP(90 angstrom)/Al(1000 angstrom) and ITO/SubPc/ C-60/BCP(90 angstrom)/Al(1000 angstrom) organic solar cells. We observed that the dark saturation current and the V-OC values vary in the CuPc/C-60 solar cells, whereas almost no variation of the dark saturation current and V-OC values in SubPC/C-60 solar cells occur. All SubPC devices show almost similar value of dark current. These differences may be attributed to the surface morphologies of planar CuPc and non-planar SubPC donor layers.