Effect of High-κ Dielectric Layer on 1/f Noise Behavior in Graphene Field-Effect Transistors

We report the 1/ f noise characteristics at low frequency in graphene field-effect transistors that utilized a high-κ dielectric tantalum oxide encapsulated layer (a few nanometer thick) placed by atomic layer deposition on Si 3 N 4 . A low noise level of ∼2.2 × 10 –10 Hz –1 has been obtained at f = 10 Hz. The origin and physical mechanism of the noise can be interpreted by the McWhorter context, where fluctuations in the carrier number contribute dominantly to the low-frequency noise. Optimizing fabrication processes reduced the number of charged impurities in the graphene field-effect transistors. The study has provided insights into the underlying physical mechanisms of the noise at low frequency for reducing the noise in graphene-based devices.