Mechanical Deformation of Single- and Few- Layer Graphene on Micro-Scale-Grooved PDMS*

The physical properties of the material graphene are currently of wide interest. To explore their mechanical aspects, we placed graphene flakes, of thicknesses ranging from one to seven layers, on a rubbery PDMS (polydimethylsiloxane) substrate containing microgrooves. We used Atomic Force Microscopy (AFM) imaging techniques to study the resulting deformations of the surface, and found that the graphene adhered to the sample and substantially flattened the profile of the grooves. We have examined this flattening effect within a model based on linear elasticity theory. Thus, we have been able to identify, at least tentatively, the point at which shear stress breaks the interlayer coupling and causes the graphene layers to slide against each other.