Mechanism of Electric Field Induced Conductance Transition in Molecular   Organic Semiconductor Based Thin Films
  We have studied the electrical field induced conductance transition in thin film of Perylenetetracarboxylic dianhydride sandwiched between two metal electrodes, from an insulating state to conducting state with a high ON-OFF ratio in those devices, where one of electrodes is either Al or Cu. Temperature dependence of resistivity shows semiconducting behavior in OFF-state, but it shows metallic behavior in the ON-state. Devices with a thin intermediate layer of LiF between metal electrode and organic layer, or devices fabricated in planar configuration do not show switching behavior. All these suggest that conducting pathways are responsible for the electric field induced conductance transition. 
Ruchi Agrawal and Subhasis Ghosh