Mechanism of graphene adhesion to SiO2 after He+ ion beam bombardment determined by SERS

Mechanism of CVD graphene adhesion to SiO2 substrate under 100 keV He+ ions bombardment is investigated. This process in addition to creating defects in graphene lattice induces dangling bonds in the glass substrate and leads to strong increase of adhesion of graphene to the substrate. It is shown that creation of covalent bonds between graphene and substrate is responsible for increase of adhesion of graphene to SiO2. Surface Enhance Raman Spectroscopy (SERS) measurements reveled characteristic for carbonates CO3 complex line at 1078 cm−1, which proves that formation of covalent CO bonds takes place. SERS results indicate that the area around of kicked off carbon atom has to contain several carbon – oxygen bonds. Strong increase of scratch resistance of ion implanted graphene on the surface of SiO2 substrate appear when overlapping of defect areas take place.