Solution-Processed Ion-Free Organic Ratchets with Asymmetric Contacts.

Abstract

Ion-free organic ratchets with asymmetric injecting contacts (AICs) are fabricated using solution-processable organic semiconductors. Scanning Kelvin probe microscopy analysis reveals that the rectifying function is achieved via the "charge pump" mechanism. Electrical characterizations show that the device can readily operate under industrial standard radio frequency and its high-frequency performance may be enhanced through further material/device engineering. The built-in asymmetric feature exempts the devices from the complicated material design, device processing, and performance decay associated with the use of ion/semiconductor blends in ionic-organic ratchets. Thus, the AIC ratchets can deliver a persisting ratchet effect and have excellent material compatibility toward organic semiconductors.