• graphene;
  • transistor;
  • ion irradiation;
  • transport gap


We demonstrate the current on-off operation in a novel dual-gated transistor with a He ion irradiated graphene channel in which defect-induced transport gap is formed. The transistor operation was performed by controlling the band configuration of gate-controlled p-i-n junction by independent biasing of top gates. The maximum current on-off ratio of nearly four orders of magnitude was obtained at a temperature of 250 K in the proposed device structure. It was also demonstrated that the transistor polarity can be changed between unipolar and ambipolar just by adjusting the gate bias of one of the dual gates, as expected from the device operation model. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)