Low-voltage-operated top-gate polymer thin-film transistors with high capacitance poly(vinylidene fluoride-trifluoroethylene)/poly(methyl methacrylate) dielectrics

We report on low-voltage-operated polymer transistors with poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)]/poly(methyl methacrylate) (PMMA) blended films as a gate dielectric layer. Top-gate polymer transistors are fabricated by all-solution processes on poly(9,9-dioctylfuorene-co-bithiophene) (F8T2) as an active layer. Both the operating voltage and charge carrier mobility are improved using P(VDF-TrFE)/PMMA blended films as a dielectric layer and by optimization of the ratio of the composite. F8T2 transistors have a high field-effect mobility of 1 x 10(-2) cm(2)/V s and a low operation gate voltage of less than 10 V. The operation voltage effectively decreases owing to the high permittivity of the P(VDF-TrFE)]/(PMMA) blended film (10.4-8.4). The hysteresis induced by the ferroelectric polymer effectively disappears with the addition of a small amount of amorphous PMMA (5 wt%). (C) 2010 American Institute of Physics. [doi:10.1063/1.3511697]