High-Mobility Few-Layer Graphene Field Effect Transistors Fabricated on Epitaxial Ferroelectric Gate Oxides

The carrier mobility of few-layer graphene (FLG) field-effect transistors increases tenfold when the SiO₂ substrate is replaced by single-crystal epitaxial Pb (Zr₀. ₂Ti₀. ₈) O₃ (PZT). In the electron-only regime of the FLG, reaches 710^4 cm^2/V s at 300 K for n=2. 410^12/cm^2, 70% of the intrinsic limit set by longitudinal acoustic (LA) phonons; it increases to 1. 410^5 cm^2/V s at low temperature. The temperature-dependent resistivity (T) reveals a clear signature of LA phonon scattering, yielding a deformation potential D=7. 80. 5 eV.