抄録
Charge carrier generation and charge carrier separation in organic photoreceptors are reviewed with attention to the dissociation processes of excitons into free carriers. Special emphasis has been placed on the striking differences in the mechanism of the charge carrier formation process between organic and inorganic semiconductors. Two dominant mechanisms of exciton dissociation caused by an electrostatic field are reviewed : (a) due to the Schottky-barrier, and (b) due to the local field caused by ionically-adsorbed oxygen molecules. The former is discussed on the basis of a merocyanine solar cell and the latter through the thermal photocurrent-quenching effect observed in β-copper phthalocyanine. The above dissociation processes occur, more or less, at the same time in all organic photoreceptors. Hence, photoreceptors should be designed by taking into consideration which mechanism prevails.
