CHARGE TRANSPORT AND TRAPPING AT THE INTERFACE IN 2-LAYER ORGANIC PHOTOCONDUCTORS

Photocarrier generation and injection processes in two-layer organic photoconductors consisting of a charge generation layer (CGL) and a charge transport layer (CTL) were studied by using photoacoustic and xerographic discharge techniques. The photoacoustic method provides the photocarrier generation efficiency in the CGL. On the other hand, the xerographic efficiency includes both the photocarrier generation efficiency in the CGL and the injection efficiency at the CGL/CTL interface. From a comparison of the two experimental results, we evaluated the injection efficiency of holes at the CGL/CTL interface. The injection efficiency is determined by the trapping of holes at the CGL/CTL interface. © 1989.