Band-Edge Conduction in Amorphous Semiconductors
Numerous experiments have shown that the conduction process near the band edges of amorphous semiconductors differs from that in crystals. Three possible explanations for the anomalies have been proposed: long-range potential fluctuations, hopping in band tails, and polaron formation. In this paper the transport energy description will be used to show in a transparent way how band-tail hopping may cause the anomalous transport. Transient measurements provide additional evidence for hopping. In the band-tail-hopping regime, the mobility edge plays no direct role in transport phenomena.
KeywordsTransport Energy Chalcogenide Glass Transport State Amorphous Semiconductor Band Tail
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