Reduction of 1/f Noise in Graphene after Electron-Beam Irradiation

TL;DR

This study demonstrates that electron-beam irradiation reduces 1/f noise in graphene devices, likely due to mobility fluctuation mechanisms, which enhances their potential for electronic applications.

Contribution

It provides the first evidence that defect-induced disorder via electron-beam irradiation can decrease 1/f noise in graphene, supported by experimental and theoretical analysis.

Findings

1/f noise decreases with increased irradiation-induced defects

Noise spectral density reduced by an order of magnitude at specific radiation doses

Results suggest mobility fluctuations are key to understanding noise behavior in graphene

Abstract

We investigated 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 reveals an anomalous characteristic - it 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 104 micro-C/cm^2. Our theoretical considerations suggest that the observed noise reduction after irradiation can be more readily explained if the mechanism of 1/f noise in graphene is related to the electron-mobility fluctuations. The obtained results are important for the proposed graphene applications in analog, mixed-signal and radio-frequency systems, integrated circuit interconnects and sensors.