Silicon intercalation into the graphene-SiC interface

TL;DR

This study investigates how excess silicon at the graphene-vacuum interface intercalates into the graphene-SiC interface at high temperatures, revealing rapid diffusion and successful intercalation of approximately six monolayers of silicon.

Contribution

It demonstrates the process and conditions for silicon intercalation into the graphene-SiC interface using advanced microscopy and spectroscopy techniques.

Findings

Silicon rapidly diffuses to the interface above 1020°C.

Approximately 6 monolayers of silicon can be intercalated.

Intercalation is achieved through sequential depositions.

Abstract

In this work we use LEEM, XPEEM and XPS to study how the excess Si at the graphene-vacuum interface reorders itself at high temperatures. We show that silicon deposited at room temperature onto multilayer graphene films grown on the SiC(000[`1]) rapidly diffuses to the graphene-SiC interface when heated to temperatures above 1020. In a sequence of depositions, we have been able to intercalate ~ 6 ML of Si into the graphene-SiC interface.