Cross-sectional imaging of graphene-based devices

The 2D structure and excellent electronic properties of graphene have generated worldwide interest, and offer the potential to overcome the limitations of silicon electronics.1 Early graphene-based devices consisted of a single atomic layer, but the possibility of tailoring electronic properties by stacking several different 2D crystals atop each other has since been discovered.2–5 In the assembly of these multilayer heterostructures, unwanted materials can become trapped between layers, adversely affecting the device quality. Understanding the cause of performance variations and thereby optimizing the properties of these devices is an extremely challenging task.