Photovoltaic Characteristics of Copper Phthalocyanine-poly(p-phenylene) Co-evaporation Films

Abstract

Copper phthalocyanine (CuPc) and poly(p-phenylene) (PPP) composite films (CuPc-PPP) were produced by a simultaneous deposition method. Schottky barrier photovoltaic cells consisting of semitransparent aluminum and CuPc-PPP composite films were fabricated. The effects of composition and optimization on the photovoltaic properties of the CuPc-PPP composite films by simultaneous deposition were investigated. The short circuit photocurrent of the CuPc-PPP cells increased in comparison with that of the CuPc film. This behavior was described as follows. One is that an effective surface area of the CuPc is increased by the PPP, which functions as a binder polymer. The other is that the bulk conductivity of the composite film is improved by the PPP, which functions as a carrier transfer material (CTM) for CuPc. It is found that the optimum conditions for simultaneous evaporation are as follows; film thickness: 1200 Å, deposition ratio: 5: 1.25 Å/S (CuPc: PPP), temperature: room-temperature. The power conversion efficiency under these conditions was found to be 2.33%.