Realization of a High Mobility Dual-gated Graphene Field Effect Transistor with Al2O3 Dielectric

摘要

We fabricate and characterize dual-gated graphene field-effect transistors(FETs) using Al2O3 as top-gate dielectric. We use a thin Al film as anucleation layer to enable the atomic layer deposition of Al2O3. Our devicesshow mobility values of over 8,000 cm2/Vs at room temperature, a finding whichindicates that the top-gate stack does not significantly increase the carrierscattering, and consequently degrade the device characteristics. We propose adevice model to fit the experimental data using a single mobility value.