Graphene Nanoribbon Etching for Quantum Devices

Two dimensional transition metal dichalcogenides (TMDs) are atomically thin semiconducting materials which consist of a transition metal layer sandwiched between two layers of chalcogen atoms. These materials have shown great promise in future generations of transistors and for defect-based quantum technologies. TMD device electrical properties are difficult to study and tune without proper interconnects due to the Schottky barrier that forms at the metal-semiconductor interface. Connecting graphene nanoribbons (GNRs) on top of the TMD is used to address this problem. Conventional clean room methods of fabrication for these GNRs leaves polymer residues and some require pretreatment of the sample which is not compatible with high resolution scanning probe microscopy. To alleviate this issue, a novel technique known as electrode-free local anodic oxidation (EFLAO) is used. This method utilizes an alternating current-driven electrochemical reaction to oxidize graphene in a humid environment. This can achieve residue free patterns on graphene with no pretreatment to the sample. To acquire these results, a high yield of graphene flakes was achieved first. The focus was then to learn and operate an atomic force microscope . Etching of the graphene flakes was accomplished along with fine tuning of the AFM parameters.