The flexible non-volatile memory devices using oxide semiconductors and ferroelectric polymer poly(vinylidene fluoride-trifluoroethylene)

Abstract
We demonstrated flexible ferroelectric gate thin-film transistors (Fe-TFTs) with ferroelectric polymer poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)] and amorphous indium gallium zinc oxide (a-IGZO) channel on the polyethylene-naphthalate (PEN) substrate. First, we confirm basic ferroelectric properties of the P(VDF-TrFE) film on the PEN substrate with various bending radius. Next, we fabricated Fe-TFTs with Al/120 nm-P(VDF-TrFE)/40 nm-IGZO top gate structure. Excellent electrical characteristics are demonstrated and nonvolatile memory function was confirmed with a memory window of 8.4 V. A subthreshold voltage swing of 400 mV/decade, Ion/Ioff ratio of more than 107 and the field-effect mobility of ∼1 cm2/Vs were obtained.