Reduction of 1/f noise in graphene after electron-beam irradiation

We investigated experimentally the effect of the electron-beam irradiation on the level of the low-frequency 1/f noise in graphene devices. It was found that 1/f noise in graphene reduces with increasing concentration of defects induced by irradiation. The increased amount of structural disorder in graphene under irradiation was verified with micro-Raman spectroscopy. The bombardment of graphene devices with 20-keV electrons reduced the noise spectral density, S-I/I-2 (I is the source-drain current) by an order-of magnitude at the radiation dose of 10(4) mu C/cm(2). We analyzed the observed noise reduction in the limiting cases of the mobility and carrier number fluctuation mechanisms. The obtained results are important for the proposed graphene applications in analog, mixed-signal, and radio-frequency systems, integrated circuits and sensors. (C) 2013 AIP Publishing LLC [http://dx.doi.org/10.1063/1.4802759]