A transistor is provided comprising: a substrate; a gate electrode; a semiconducting material not located between the substrate and the gate electrode; a source electrode in contact with the semiconducting material; a drain electrode in contact with the semiconducting material; and a dielectric material in contact with the gate electrode and the semiconducting material; wherein the semiconducting material comprises: 1-99.9% by weight of a polymer having a dielectric constant at 1 kHz of greater than 3.3; 0.1-99% by weight of a functionalized pentacene compound as described herein.