Defect Healing in Graphene via Rapid Thermal Annealing with Polymeric "Nanobandage".

Abstract

Overcoming throughput challenges in current graphene defect healing processes, such as conventional thermal annealing, is crucial for realizing post-silicon device fabrication. Herein, a new time- and energy-efficient method for defect healing in graphene is reported, utilizing polymer-assisted rapid thermal annealing (RTA). In this method, a nitrogen-rich, polymeric "nanobandage" is coated directly onto graphene and processed via RTA at 800 °C for 15 s. During this process, the polymer matrix is cleanly degraded, while nitrogen released from the nanobandage can diffuse into graphene, forming nitrogen-doped healed graphene. To study the influence of pre-existing defects on graphene healing, lattice defects are purposefully introduced via electron beam irradiation and investigated by Raman microscopy. X-ray photoelectron spectroscopy reveals successful healing of graphene, observing a maximum doping level of 3 atomic nitrogen % in nanobandage-treated samples from a baseline of 0-1 atomic % in non-nanobandage treated samples. Electrical transport measurements further indicate that the nanobandage treatment recovers the conductivity of scanning electron microscope-treated defective graphene at ≈85%. The reported polymer-assisted RTA defect healing method shows promise for healing other 2D materials with other dopants by simply changing the chemistry of the polymeric nanobandage.