Graphene growth on h-BN by Molecular Beam Epitaxy

TL;DR

This paper demonstrates the controlled growth of single-layer graphene on h-BN substrates using molecular beam epitaxy, highlighting the influence of substrate morphology and temperature on growth quality.

Contribution

It introduces a novel method for graphene growth on h-BN via molecular beam epitaxy, emphasizing the role of surface morphology and temperature in the process.

Findings

Graphene growth depends on h-BN surface morphology.

Growth is governed by high carbon atom mobility on h-BN.

Substrate temperature critically affects graphene layer formation.

Abstract

The growth of single layer graphene nanometer size domains by solid carbon source molecular beam epitaxy on hexagonal boron nitride (h-BN) flakes is demonstrated. Formation of single-layer graphene is clearly apparent in Raman spectra which display sharp optical phonon bands. Atomic-force microscope images and Raman maps reveal that the graphene grown depends on the surface morphology of the h-BN substrates. The growth is governed by the high mobility of the carbon atoms on the h-BN surface, in a manner that is consistent with van der Waals epitaxy. The successful growth of graphene layers depends on the substrate temperature, but is independent of the incident flux of carbon atoms.