Leakage conduction behavior for top- and bottom-contact pentacene thin film transistors

The leakage conduction mechanisms for top-contact and bottom-contact pentacene-based organic thin film transistors (OTFTs) are studied. OTFTs that use a bottom-contact design exhibit lower leakage conduction than those that use a top-contact design. For top-contact OTFTs, the dominant leakage conduction mechanism is via Schottky emission and the density of the leakage current increases significantly as the bias voltage increases. For bottom-contact OTFTs, the dominant leakage conduction mechanism is via displacement current. OTFTs that use a bottom-contact design exhibit lower leakage conduction than those that use a top-contact design.