Conductivity change of defective graphene by helium ion beams

Yuichi Naitou,Shinichi Ogawa

doi:10.1063/1.4979983

Abstract

Applying a recently developed helium ion microscope, we demonstrated direct nano-patterning and Anderson localization of single-layer graphene (SLG) on SiO2/Si substrates. In this study, we clarified the spatial-resolution-limitation factor of direct nano-patterning of SLG. Analysis of scanning capacitance microscopy measurements reveals that the conductivity of helium ion (H+)-irradiated SLG nanostructures depends on their geometrical size, i.e., the smaller the H+-irradiated SLG region, the higher its conductivity becomes. This finding can be explained by the hopping carrier transport across strongly localized states of defective SLG.

Highlights

Due to its superior, often surprising electrical and mechanical properties, graphene has currently attracted much interest in basic physics as well as applied device physics.[1,2,3] Graphene-based devices are commonly fabricated using electron-beam (EB) lithography with subsequent plasma etching.[4,5,6] EB lithography requires photoresist processing, which contaminates the graphene surface and degrades its transport properties
We investigated the impact of accelerated helium ion (He+)-beam irradiation of graphene using the recently developed Orion Plus helium ion microscope (HIM) and demonstrated direct nanoscale patterning of graphene.[7]
Current flowing between probe tip of Conductive AFM (C-AFM) and graphene surface induce anodic oxidation

Summary

Introduction

Often surprising electrical and mechanical properties, graphene has currently attracted much interest in basic physics as well as applied device physics.[1,2,3] Graphene-based devices are commonly fabricated using electron-beam (EB) lithography with subsequent plasma etching.[4,5,6] EB lithography requires photoresist processing, which contaminates the graphene surface and degrades its transport properties. Conductivity change of defective graphene by helium ion beams

Results

Conclusion