Since the first report on heterojunction-type organic solar cells using a phthalocyanine by Tang in 1986, the phthalocyanines have been widely used for the organic solar cells owing to their long exciton diffusion length, large absorption coefficients, high charge generation efficiency and high thermal stability at room temperature. In general, the phthalocyanine-based organic solar cells can be fabricated by vacuum deposition techniques due to their poor solubility to organic solvents.
In this study, characterization of zinc phthalocyanine-based coating-type solar cells fabricated by using various kinds of organic solvents is performed. High photoelectric conversion efficiency of 6.39×10^-4 is obtained for the solar cell prepared by a mixture of chloroform (CF) and chlorobenzene (CB) (CF:CB=3:1). The difference of the conversion efficiencies between the fabricated solar cells is discussed in terms of molecular aggregation and crystallinity of the films.