Plasma-enhanced atomic layer deposition of Al2O3 on graphene via an in situ-deposited interlayer

A novel method has been developed for the deposition of high-κ dielectrics on graphene, which uses a nonstoichiometric aluminum oxide (AlOX) protective layer. This approach employs mild plasma conditions to directly grow a thin AlOX layer on graphene, followed by the deposition of aluminum oxide (Al2O3) via plasma-enhanced atomic layer deposition (PEALD) without breaking the vacuum. A sub-3 nm AlOX layer provides effective protection for graphene and facilitates the formation of functional groups, thereby enabling the deposition of high-quality dielectrics without damaging the graphene. Top-gated graphene field-effect transistor (GFET) devices fabricated via this method demonstrated an electric field strength above 11 MV/cm and an equivalent oxide thickness (EOT) of less than 5 nm on a wafer scale. This deposition technique addresses a significant challenge in transitioning next-generation graphene-based electronics from the laboratory to industrial production.