Damage Effect Of Low-to-intermediate Energy Proton Irradiation On Single Layer Graphene

Single layer graphene(SLG),a two-dimensional honeycomb material formed by sp2 hybridization of single layer carbon atoms.Its thickness is only 0.335 nm and the world’s thinnest,hardest and the highest strength of the material.Due to its extraordinary matertial properties,it have great potential and development prospects in the electronic components,photon sensors,thermal materials,gene sequencing and other industries.But because of its zero bandgap,it is limited in the electronic device further application on some extent.In order to introduce defects in graphene by ion irradiation and then open the band gap and study the similarities and differences on interaction between ion beam and the two-dimensional material and the three-dimensional block material.In this work,we study the radiation damage effect on SLG of different energy proton beams,and the main work is divided into three parts.1.750 keV and 1 MeV proton beam irradiate SLG on silicon substrate.2.Comparison of radiation damage effects of SLG on different substrates irradiated by 1 MeV proton beam.3.Comparison of radiation damage effects of SLG on silicon substrates and suspended SLG irradiated by 1 MeV proton beam.By comparing the Raman spectrum of graphene before and after irradiation,the following important phenomenon are found:1、When the proton energy is between 150-400 keV,the damage on SLG on the silicon substrate caused by proton bombardment appear opposite trend with the energy loss of the proton in silicon and carbon,that is,the smaller the energy loss,the greater the damage.This is exactly opposite with the experimental properties of several MeV proton.The correctness of the main experiment finding are fully validated via repeating to verify the experiment on different accelerators and dozens of Raman points with the uniform distribution on each target are carried out.2、In the 100-400 keV energy region,the damage SLG on the silicon substrate caused by the proton beam is much greater than that caused on self-supporting SLG.This characteristic is remarkably different from the MeV energy region.above MeV energy region can be found the damage of self-supporting SLG is greater than that of single layer graphene in the international experiments.In addition to the above important findings,the research work has the following conclusions:1.The ID / IG increases with the increase of the energy of the incident proton at 750 keV ~ 2.2 MeV,and coincides with the trend of the simulation result of the SRIM.The average distance of the defect LD increases with the energy of the incident proton,the defect density nD decreases with the increase of the incident proton energy.This indicates that the damage effect of the proton in graphene is similar to that of the three-dimensional material.2.The damage effect of the 1 MeV proton beam on SLG on silicon substrate is greater than that of SLG on copper substrate.