Production of Large‐Area Nucleus‐Free Single‐Crystal Graphene‐Mesh Metamaterials with Zigzag Edges

Abstract

In addition to conventional monolayer or bilayer graphene films, graphene‐mesh metamaterials have attracted considerable research attention within the scientific community owing to their unique physical and optical properties. Currently, most graphene‐mesh metamaterials are fabricated using common lithography techniques on exfoliated graphene flakes, which require the deposition and removal of chemicals during fabrication. This process may introduce contamination or doping, thereby limiting their production size and application in nanodevices. Herein, the controlled production of wafer‐scale high‐quality single‐crystal nucleus‐free graphene‐mesh metamaterial films with zigzag edges is demonstrated. The 13C‐isotopic labeling graphene‐growth approach, large‐area Raman mapping techniques, and a uniquely designed high‐voltage localized‐space air‐ionization etching method are utilized to directly remove the graphene nuclei. Subsequently, a hydrogen‐assisted anisotropic etching process is employed for transforming irregular edges into zigzag edges within the hexagonal‐shaped holes, producing a large‐scale single‐crystal high‐quality graphene‐mesh metamaterial film on a Cu(111) substrate. The carrier mobilities of the fabricated field‐effect transistors on the as‐produced films are measured. The findings of this study enable the large‐scale production of high‐quality low‐dimensional graphene‐mesh metamaterials and provide insights for the application of integrated circuits based on graphene and other 2D metamaterials.

From Top to Down—Recent Advances in Etching of 2D Materials

“…b-e) Reproduced with permission. [78] Copyright 2022, Wiley-VCH. f) AFM images of hexagon flower-etched Cu patterns embedded into large-scale graphene located on a liquid Cu/W substrate.…”

“…The results indicates that the nucleus free zigzag-edge features improved the electronic transport properties of graphene nanomesh materials. [78] A contamination-free and physical contact-free approach was proposed in this study in which the 2D mesh materials were prepared by the assistance of etching. Importantly, this method can be utilized for the etching and patterning of other 2D materials in the development of waferscale 2D heterostructures in the future.…”

“…e) Schematic of the FETs based on the GMM film fabricated on the SiO 2 /Si substrate. b-e) Reproduced with permission [78]. Copyright 2022, Wiley-VCH.…”

Morphology‐Control Growth of Graphene Islands by Nonlinear Carbon Supply

“…[41] Graphene was attached to a two-layer (111) slab cleaved from face-centered cubic Cu and augmented in the out-of-plane direction with a vacuum slab of 12 Å thickness. The energetically favorable stacking was taken from previous work [34] to construct 8 × 8 × 1 and 12 × 12 × 1 supercells. Models of petal-, hexagonal-, and circular-shaped graphene islands with small, medium, and large sizes were built.…”

“…Notably, in all cases, the as-synthesized hexagonal graphene islands exhibited extremely sharp and straight edges, which suggests that the edges of these hexagonal islands have a zigzag atomic arrangement consistent with the earlier claim. [31][32][33]…”