Charge transfer in ZnS-type electroluminescence revisited

Abstract
Electrical characteristics of ac-driven, undoped ZnS electroluminescent layers are reported over a large temperature range. They show that, contrary to the currently assumed model of charge transfer wherein electrons are exchanged between the two ZnS interfaces, the operation involves an appreciable bulk charge evolving through capture and recombination of incident carriers. The meaning of the basic electrical observables is revisited. The results have relevance to the operation of blue emitting SrS-based electroluminescent devices.