Carrier Injection from Photoconductors into Insulating Liquid

Abstract

From a viewpoint of electrophotographic applications, fundamental aspects of the photoinjection of charge carriers from a photoconductor into an insulating liquid were studied. Steady state photoinjection currents were measured in a sandwich structure, Au/a-Se or a-As2Sedliquid paraffin/Au, with or without chemical additives in the liquid layer.
The photoinjection current varied linearly against the applied voltage only in a narrow range of experimental conditions, and over that range, the currents showed a superlinear and a sublinear dependences, successively. The log J vs. log V curve changed as a function of the photoconductor, the insulating liquid and the additive used, and also of the polarity of injected carriers. The photoinjection current scarcely depended on the light intensity, and it is independent of the nature and the concentration of additives. Ionizable additives tended to increase photo- and dark-current, injected charges being stabilized and transported by the added molecules. On the other hand, there were some evidences found that the ions produced from additives at the interface region worked to retard the photoinjection by forming a space-charge layer there.