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This work presents a suspended graphene ribbon device for electrostatic discharge (ESD) applications. The device structure was proposed and fabricated after careful design considerations. Compared to the conventional ESD devices such as diodes, bipolar junction transistors, and metal-oxide-semiconductor field effect transistors, the proposed device structure is believed to render several advantages including zero leakage, low parasitic effects, fast response, and high critical current density. A process flow was developed for higher yield and reliability of the suspended graphene ribbons. Direct current (DC) and transmission-line pulse (TLP) measurements were carried out to investigate the switching behavior of the device, which is crucial for ESD operation. DC measurements with a different configuration were used to assess the mechanical shape evolution of the graphene ribbon upon biasing. Finite Element Simulations were conducted and agreed well with the experimental results. Furthermore, the current carrying capability of non-suspended graphene ribbons was tested using TLP. It was found that the critical current density of graphene is higher than that of copper wires widely used as interconnects in integrated circuits (ICs).

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Graphene is a two-dimensional carbon material with extraordinary mechanical properties. However, recent studies have found that the presence of grain boundaries significantly decreases fracture stress of graphene, warranting further investigation. This work reports the development of a new method to measure the fracture stress of monolayer graphene with a novel nanoelectromechanical system (NEMS) structure. Suspended graphene ribbon devices with a range of geometries were electrostatically actuated while the graphene sheet was pinned down with various nail structures. By recording the electromechanical responses at fracture and using finite element simulations, the fracture stress was calculated. Using this novel NEMS structure, the fracture stress of polycrystalline graphene grown using conventional chemical vapour deposition (CVD) and single-crystalline graphene grown using local feeding CVD were found to be ∼30 and ∼90 GPa, respectively.