Graphene functionalization and seeding for dielectric deposition and device integration

Abstract

Graphene has recently attracted wide-spread attention because of its unique transport and physical properties that are appealing for a wide range of electronic applications. Integration with scalable high-κ dielectrics is important for the realization of graphene-based top-gated electronic devices, including next generation THz applications. Atomic layer deposition (ALD), a low temperature deposition method based on two separate self-limiting surface reactions, is a preferred technique to achieve high-quality, conformal, ultrathin dielectric films with precise control of thickness and chemical composition at the atomic scale. Unfortunately, ALD of oxides on graphene is hindered by the inertness of the graphene surface. To alleviate this graphene-oxide incompatibility, several different functionalization and seeding methods have recently been developed to render the graphene more susceptible to the ALD process of high-κ dielectrics including: ozone, wet chemical and fluorine pretreatments, low-k polymer seed, e-beam metal, and oxide seed layers. The ability of each approach to enable conformal, uniform high-κ dielectrics on graphene while maintaining its inherent transport properties for low power, high-frequency device applications is discussed.