Adlayer‐Free Large‐Area Single Crystal Graphene Grown on a Cu(111) Foil

Abstract

To date, thousands of publications have reported chemical vapor deposition growth of “single layer” graphene, but none of them has described truly single layer graphene over large area because a fraction of the area has adlayers. It is found that the amount of subsurface carbon (leading to additional nuclei) in Cu foils directly correlates with the extent of adlayer growth. Annealing in hydrogen gas atmosphere depletes the subsurface carbon in the Cu foil. Adlayer‐free single crystal and polycrystalline single layer graphene films are grown on Cu(111) and polycrystalline Cu foils containing no subsurface carbon, respectively. This single crystal graphene contains parallel, centimeter‐long ≈100 nm wide “folds,” separated by 20 to 50 µm, while folds (and wrinkles) are distributed quasi‐randomly in the polycrystalline graphene film. High‐performance field‐effect transistors are readily fabricated in the large regions between adjacent parallel folds in the adlayer‐free single crystal graphene film.

Chemical Vapour Deposition of Graphene—Synthesis, Characterisation, and Applications: A Review

“…Copper has stable electronic configuration which limits its reaction with C atoms to weak forces and reduces the bulk diffusion of C atoms in Cu substrate [21]. This gives copper an advantage in growing single layer graphene, where the process progresses on the surface [21,139]. Experimenting with different metal substrates, copper soon raised as an excellent substrate for CVD growth of Graphene [38,91,[138][139][140].…”

“…This gives copper an advantage in growing single layer graphene, where the process progresses on the surface [21,139]. Experimenting with different metal substrates, copper soon raised as an excellent substrate for CVD growth of Graphene [38,91,[138][139][140]. Early work by Li et al found that the low C solubility of copper at high temperatures reduces precipitation on the surface and results in more uniform single-layer graphene growth [38].…”

“…Copper has stable electronic configuration which limits its reaction with C atoms to weak forces and reduces the bulk diffusion of C atoms in Cu substrate [21]. This gives copper an advantage in growing single layer graphene, where the process progresses on the surface [21,139].…”

“…Copper has stable electronic configuration which limits its reaction with C atoms to weak forces and reduces the bulk diffusion of C atoms in Cu substrate [21]. This gives copper an advantage in growing single layer graphene, where the process progresses on the surface [21,139]. While the surface diffusion of reaction limits the graphene growth to single layer upon coverage of the copper surface, it has been shown that more layers can be grown on copper [51,52].…”

Sequential growth and twisted stacking of chemical-vapor-deposited graphene

“…8,9 Nowadays the most widely used approach for large-scale graphene synthesis is the chemical vapor deposition (CVD) method using Cu as the substrate, [10][11][12][13] but due to the low solubility of C in Cu and the necessity of Cu to catalyze the decomposition of methane (CH 4 ), the CVD growth of graphene on Cu is usually self-limited, i.e., MLG-dominant films are obtained. 10,14 However, these MLG films are usually decorated with few-layer graphene (FLG) regions. This is due to that, at the beginning of CVD growth, when a graphene layer nucleates on Cu surface, simultaneous growth of more layers (adlayers) underlying this layer usually starts as well.…”