Mechanism of Electric Field Induced Conductance Transition in Molecular Organic Semiconductor Based Thin Films

TL;DR

This study investigates how electric fields induce a conductance transition in organic semiconductor thin films, revealing a switch from insulating to metallic states linked to conducting pathways, with implications for device design.

Contribution

It demonstrates the mechanism of conductance transition in organic thin films and highlights the role of conducting pathways in the switching behavior.

Findings

Conductance transition from insulator to metal under electric field.

Presence of conducting pathways correlates with switching behavior.

Intermediate layers or planar configurations suppress switching.

Abstract

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.