Memory effect and negative differential resistance in tris-(8-hydroxy quinoline) aluminum/bathocuproine bilayer devices

摘要

Memory effect and negative differential resistance (NDR) were observed in simple tris-(8-hydroxyquinoline) aluminum/bathocuproine (BCP) bilayer devices. The devices could be switched from a low conductance state to a high conductance state when a negative bias was applied and could be restored to an OFF state when a positive bias was applied beyond the NDR region. The memory effect is nonvolatile, and an ON/OFF ratio of over 10~3 was achieved. The memory effect was observed only in the presence of both Alq_3 and BCP layers, and the NDR is attributed to the defects formed in the BCP layer upon evaporation of an Al cathode.