Electrical characterization of MoS₂ field-effect transistors with different dielectric polymer gate

The characteristics of MoS₂-nanoflake field-effect transistors (FETs) were studied by analyzing the transfer curves in MoS₂-FETs with ferroelectric and general polymers as the gate dielectric. A clear hysteresis, opposite to the electron trapping-detrapping effect in traditional MoS₂-FETs, was observed in the MoS₂-FETs with ferroelectric poly(vinylidene fluoride/trifluoroethylene) [P(VDF-TrFE)] films. The effect carrier mobility of MoS₂ nanoflakes reached approximately 95.6 cm²/Vs under the control of the polarization field of P(VDF-TrFE), whereas the effect carrier mobility was only approximately 15.3 cm²/Vs in MoS₂-FETs with traditional dielectric poly(methyl methacrylate) (PMMA) films. Furthermore, the ferroelectric MoS₂-FETs possess a higher ON/OFF resistance ratio (approximately 10⁷) than do the PMMA MoS₂-FETs (approximately 10⁵).