Silicon intercalation into the graphene-SiC interface

Abstract

In this work we use low-energy electron microscopy, x-ray photoemission electron microscopy, and x-ray photoelectron spectroscopy 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$(000\overline{1})$ rapidly diffuses to the graphene-SiC interface when heated to temperatures above 1020${\phantom{\rule{0.16em}{0ex}}}^{\ensuremath{\circ}}\mathrm{C}$. In a sequence of depositions, we have been able to intercalate $\ensuremath{\sim}$6 ML of Si into the graphene-SiC interface.