Abstract :
p-CuPc / n-Si heterojunction cells have been fabricated by thermal evaporation of p-type CuPc thin films onto n-Si 100 single crystal wafers. Current – Voltage and Capacitance – Voltage measurements have been performed to determine some electrical properties of these structures. Rectifying properties have been obtained, which are definitely of the diode type. The analysis of dark Current – Voltage characteristics of cells under test at several temperatures reveals some junction parameters such as: rectification ratio, the series resistance, the shunt resistance, the diode ideality factor, the potential barrier height and the reverse activation energy. The forward current involves thermionic emission as well as space charge limited current at low and high forward bias voltages respectively. The reverse current is probably limited by generation – recombination mechanism. The dark Capacitance – Voltage behavior indicates an abrupt heterojunction, with homogeneous distribution of impurities inside the space charge region. Values of conversion efficiency as high as 1.29 % and open voltage of 0.36 V were evaluated from the loaded I-V characteristics at input power of 50mW/cm2.
