Step driven competitive epitaxial and self-limited growth of graphene on copper surface

Abstract

The existence of surface steps was found to have significant function and influence on the growth of graphene on copper via chemical vapor deposition. The two typical growth modes involved were found to be influenced by the step morphologies on copper surface, which led to our proposed step driven competitive growth mechanism. We also discovered a protective role of graphene in preserving steps on copper surface. Our results showed that wide and high steps promoted epitaxial growth and yielded multilayer graphene domains with regular shape, while dense and low steps favored self-limited growth and led to large-area monolayer graphene films. We have demonstrated that controllable growth of graphene domains of specific shape and large-area continuous graphene films are feasible

Improved transport properties of graphene/GaN junctions in GaN-based vertical light emitting diodes by acid doping

“…After dissolving the underlying copper substrate in FeCl 3 aqueous solution (1 M), the floating CVD-grown graphene film 7 was transferred onto epitaxial p-GaN and n-GaN substrates which were grown on (0001) oriented sapphire substrates by metal organic chemical vapor deposition (MOCVD). The p-GaN sample contains unintentionally doped GaN (u-GaN) layer (2 mm) and p-type GaN:Mg layer (0.2 mm) in sequence.…”

Controllable growth of shaped graphene domains by atmospheric pressure chemical vapour deposition

“…Such findings can be attributed to stepdriven competitive epitaxial and self-limited growth of graphene. 19 It is also observed that near a big domain, a small domain exists as indicated by the arrow, suggesting that when methane is introduced into the reaction tube, many seeds/islands nucleate and grow into domains at certain positions. When graphene domains grow larger, new islands nucleate at the same time, which means not all domains nucleate simultaneously.…”

Evolutionary Kinetics of Graphene Formation on Copper

“…While no further nucleations were observed for the main graphene layer after the near instantaneous nucleations, secondary layers of graphene emerge around the nucleation centers of the already growing graphene flakes (Figure a). These secondary nucleations were only observed under larger flakes, resulting in smaller flakes enlarging and adhering to the top layer from their underside . The growth of these secondary layers continued until the first monolayer completely covered the surface.…”