Evidence for trap-limited transport in the subthreshold conduction regime of chalcogenide glasses

The study of the temperature dependence of subthreshold conduction in amorphous chalcogenide materials reveals a voltage dependent activation energy, which can be attributed to trap-limited conduction. The authors find that the features of subthreshold conduction regime (subthreshold slope and activation energy) can be quantitatively explained by a simple conduction model for Poole-Frenkel transport in the presence of a high concentration of traps. This analysis allows for an accurate prediction of the temperature and voltage dependence of subthreshold current in amorphous chalcogenides, and offers a simple scheme for estimating the average distance between traps in the disordered material. (C) 2007 American Institute of Physics.