Structure and photoelectric properties of copper-phthalocyanine lead telluride multilayer thin film prepared by laser ablation and thermal evaporation

We prepared highly crystallized copper-phthalocyanine (CuPc)/lead telluride (PbTe) hetero-multilayer structures for the first time. The crystallized CuPc (alpha-form) and PbTe films are formed by thermal evaporation and laser ablation techniques, respectively. Both films are grown at 300 degrees C, which is a lower growth temperature than that of other transition metal chalcogenide films. We observed the transverse current-voltage characteristics of CuPc/Si, PbTe/Si and PbTe/CuPc/Si junctions in the dark and under illumination. The PbTe/CuPc/Si junction exhibits a strong photovoltaic response with quantum efficiency of 15.4% and a power conversion efficiency of 3.46x10(-2). The photocarrier is generated in the CuPc layer and the carriers are separated by the steep incline of the potential near the CuPc/PbTe interface. The CuPc/PbTe multilayers exhibit a high level of photoconductivity in the in-plane direction.