Freestanding graphene edge probes for scanning tunneling microscope

We demonstrated the fabrication of individual freestanding graphene edge probes. Graphene was prepared by thermal CVD with solid carbon sources. A Cu wire was act as the substrate for graphene growth. Follow the structure process from a micromanipulator and an optical microscope, the freestanding graphene probes was fabricated. The electron emission pattern from the graphene edge was observed, and a layered structure could be identified from field emission microscopy. The single-layer graphene emitted electrons from limited number of atoms. The graphene emitters required careful conditioning to achieve a stable emission current. Such graphene probes were applied in scanning tunneling microscopes for surface morphology detection. A preconditioned, multi-layer graphene probe presented well resolution compared with a conventional tungsten probe. Our study reveals a practical method by individual freestanding graphene in application for surface probe microscopy.