Stacking domains in graphene on silicon carbide: a pathway for intercalation

TL;DR

This paper reveals that graphene on silicon carbide consists of domains with different stacking, and dislocations between these domains control atom intercalation, offering new pathways for electronic property tuning.

Contribution

It challenges the current view of homogeneous graphene on SiC by showing the domain structure and dislocation influence on intercalation dynamics.

Findings

Graphene on SiC is composed of stacking domains.

Dislocations between domains govern intercalation processes.

Tailoring dislocation networks can enhance intercalation control.

Abstract

Graphene on silicon carbide (SiC) bears great potential for future graphene electronic applications because it is available on the wafer-scale and its properties can be custom-tailored by inserting various atoms into the graphene/SiC interface. It remains unclear, however, how atoms can cross the impermeable graphene layer during this widely used intercalation process. Here we demonstrate that, in contrast to the current consensus, graphene layers on SiC are not homogeneous, but instead composed of domains of different crystallographic stacking. We show that these domains are intrinsically formed during growth and that dislocations between domains dominate the (de)intercalation dynamics. Tailoring these dislocation networks, e.g. through substrate engineering, will increase the control over the intercalation process and could open a playground for topological and correlated electron phenomena in two-dimensional superstructures.