Substitutional mechanism for growth of hexagonal boron nitride on epitaxial graphene

Abstract

Monolayer-thick hexagonal boron nitride (h-BN) is grown on graphene on SiC(0001), by exposure of the graphene to borazine, (BH)3(NH)3, at 1100 C. The h-BN films form ~2-m size grains with a preferred orientation of 30 relative to the surface graphene. Low-energy electron microscopy is employed to provide definitive signatures of the number and composition of twodimensional (2D) planes across the surface. These grains are found to form by substitution for the surface graphene, with the C atoms produced by this substitution then being incorporated below the h-BN (at the interface between the existing graphene and the SiC) to form a new graphene plane. * feenstra@cmu.edu

Transfer‐Free Synthesis of Lateral Graphene–Hexagonal Boron Nitride Heterostructures from Chemically Converted Epitaxial Graphene

“…Recently, an h‐BN substitution reaction was observed in epitaxial graphene by exposure to borazine at 1100 °C under vacuum resulting in an epitaxial layer of h‐BN on top of epitaxial graphene via liberation of carbon atoms from the topmost graphene layer . In our experiments, observation of CN and CB bonds in the XPS data and observation of a domain interface by STM provide evidence of an in‐plane heterostructure of graphene and h‐BN.…”

Influence of Proximity to Supporting Substrate on van der Waals Epitaxy of Atomically Thin Graphene/Hexagonal Boron Nitride Heterostructures

“…In our experiments, we used considerably lower growth temperatures and rates, and the 30°twisted domains were observed on SLG on micrometer-large terraces, far away from the step edges. On SLG, h-BN has been reported to form with a 30°relative rotation to EG via a substitutional growth above 1000 °C, 32 while the differently stacked rhombohedral BN (r-BN) has been shown to form with an epitaxial relation of r-BN[101̅ 0] // SiC[101̅ 0] on bare SiC. 68 We attribute the occurrence of the 30°rotated domains between h-BN and graphene in our samples, grown at temperatures well below 1000 °C, to a stabilization due to the potential of the SiC substrate through the SLG, which is screened by an additional layer on BLG, similar to the observations during the remote epitaxy of GaAs on graphene-covered GaAs.…”

“…Growing h-BN at high temperatures above 1000 °C on a highly oriented pyrolytic graphite via PAMBE resulted in a formation of h-BN domains, which were aligned toward graphite at a relative rotation angle of 0°, but the plasma-assisted growth also induced damage in the substrate. , Depending on the growth rate on the few-layer graphene (FLG), both orientations could be achieved above 1000 °C using chemical beam epitaxy . On the single-layer graphene (SLG), h-BN was shown to form with a 30° rotation by substituting graphene at temperatures above 1000 °C using borazine as a precursor . Besides defects and lattice matching, the vdWE on atomically thin layers is further influenced by the underlying substrate, below the 2D materials.…”

“…31 On the single-layer graphene (SLG), h-BN was shown to form with a 30°rotation by substituting graphene at temperatures above 1000 °C using borazine as a precursor. 32 Besides defects and lattice matching, the vdWE on atomically thin layers is further influenced by the underlying substrate, below the 2D materials. For GaAs/ graphene heterostructures, the potential field of the underlying substrate below graphene has been demonstrated to influence the orientation of the GaAs heterolayer.…”

Chemical vapour deposition of sp2-hybridised B-C-N materials from organoborons

“…262 Recent works report epitaxy of a few layer BN on graphene. [320][321][322] Methane can be used to compensate for the etching of the graphene template. 322…”