Investigation of charges-driven interaction between graphene and different SiO 2 surfaces

As being only one atom thick, most of the device applications require graphene to be partially or fully supported by a substrate, which is typically silicon dioxide (SiO 2 ). According to a common understanding, graphene interacts with SiO 2 through weak, long-range van der Waals forces, emerging between instantaneous/induced dipoles, in contrast to the experimental evidence that reveals a surprisingly high interaction between graphene and SiO 2 . In order to get further insight into this phenomenon, we carried out diverse physical measurements on SiO 2 substrates, prepared via different fabrication protocols, with and without graphene on top. As a result, the role of the oxide surface charges is recognized for the first time as a main factor causing graphene to strongly interact with SiO 2 . Our findings provide guidelines for designing 2D materials interaction with a substrate through modulation of surface charges. This, in turn, can facilitate the development of new graphene based microelectronic devices.