Modeling of metal-ferroelectric-insulator-semiconductor structures based on Langmuir-Blodgett copolymer films

Among the ferroelectric thin films used in field-effect transistor devices; the ferroelectric copolymer of polyvinylidene fluoride (PVDF) (-CH ₂-CF₂-), with trifluoroethylene (TrFE) (-CHF-CF ₂-), has distinct advantages, including low dielectric constant, low processing temperature, low cost, and compatibility with organic semiconductors. The operation of a metal-ferroelectric-insulator-semiconductor structure with P(VDF-TrFE) as the ferroelectric layer was analyzed and optimized by numerical solution of the Miller and McWhorter model. A model device consisting of 20 nm PVDF/TrFE on a 10-nm-thick high- k dielectric buffer exhibits a memory window of 5 V with an operating voltage of ±15 V. The operating voltage can be reduced to ±12 V by reducing the ferroelectric and dielectric thicknesses to 10 and 5 nm, respectively.