Influence of polymer gate dielectrics on n -channel conduction of pentacene-based organic field-effect transistors

This work elucidates the way polymer gate dielectrics affect the accumulation and transport of charge carriers in the active layer of organic field-effect transistors (OFETs). Incorporating a poly(vinyl alcohol) polymer interfacial film and another cross-linked poly(4-vinyl phenol) layer as a double-layer gate dielectric causes the pentacene-based OFETs to exhibit effective n -channel conduction of a saturated, apparent pinch-off drain-source current with the electron mobility of ∼0.012 cm2 V-1 s-1. The formation of an n channel in the pentacene layer is supported by the increased capacitance that is identified by the quasistatic capacitance-voltage measurements of devices with the metal-insulator-semiconductor configuration, biased at a positive gate voltage, in the n -type accumulation regime.