Study of the electronic structure of amorphous silicon using reverse-recovery techniques

Abstract
We have carried out a series of reverse‐recovery experiments on pin diodes of amorphous‐Si:F:H of thicknesses up to 3.5 μm under pulsed high‐level injection conditions. No evidence for charge storage was obtained. Our results indicate that the room‐temperature band mobility for electrons moving near the mobility edge in a‐Si:F:H is larger than 100 cm2/Vs. In addition, our data suggest that either an intrinsic or induced gap exists in the density of localized states below the conduction‐band mobility edge, in surprising contrast with conclusions deduced from a variety of recent experiments.