Low-frequency noise in graphene field-effect transistors

The low frequency noise has been studied in mechanically exfoliated single- and bilayer graphene deposited on Si/SiO2 substrates. Measurements were performed in 2- and 4-probe configuration schemes. The analysis of the gate voltage dependences of noise showed that noise in graphene transistors does not comply with the McWhorter model. Aging of graphene transistors due to exposure to ambient resulted in increased noise attributed to the decreasing mobility of graphene and increasing contact resistance. The model linking noise in graphene to the mobility fluctuations is discussed.