Electrical properties of amorphous semiconductor selenium and its alloys: I. Monolayers

Various monolayer a-Se-based photoreceptor devices were fabricated by vacuum evaporation and their electrical properties were investigated. Three experimental techniques, namely xerographic time of flight (XTOF), electroded time of flight (TOF) and xerographic discharge were used to determine the drift mobility, carrier lifetime, dark decay and residual voltage. Where possible, these measurements were carried out as a function of applied field and composition, namely As approximately 0.3 wt.%, Te up to 17 wt.% and Cl up to 60 ppm. The addition of As or Te alone reduced both hole and electron drift mobilities and increased the carrier lifetime.