Study of dark electrical properties and photoelectric performance of organic/inorganic (ZnPc/p-Si) Solar cells

Abstract

Abstract A Zinc Phthalocyanine (ZnPc) film was deposited by thermal evaporation on a monocrystalline p-Si substrate to provide a p-ZnPc/p-Si organic/inorganic heterojunction. The electrical characteristics of the fabricated cell were examined by measuring the current density versus voltage (J-V). The fabricated cell was characterized by a contact barrier of 0.56 eV and a rectification ratio of 230 calculated at ± 1 V−1. The dark J-V measurement suggested that the DC current density in this junction contains a thermionic conduction mechanism when the applied voltage is relatively low. At higher voltages another conduction is dominated called the space-charge limited conduction mechanism (SCLC) controlled by a single trapping level. The I-V measurement was performed with an illumination of 100 mWcm−2 and the photoelectric conversion characteristics of the junction were also studied, achieving a power conversion efficiency of 2.7%. The other solar cell parameters such as the short-circuit current Isc, the open-circuit voltage Voc and the filling factor FF were evaluated and equaled to 2.5 A, 1.132 V and 0.477 at room temperature. The dependence of these parameters as a function of the temperature has also been studied in the temperature range from 300 to 400 K.