Cu Intercalation under a Zero Layer Graphene Grown on a SiC(0001) Surface

Abstract

Graphene has attracted much attention since the discovery of its superior carrier-transport-properties. In this paper, we report the intercalation of Cu atoms under a zero layer graphene (ZLG) formed on a SiC(0001) substrate, which makes a “free-standing” single layer graphene. Cu atoms are deposited on the ZLG at room temperature. After annealing of the substrate above 600℃, it is confirmed by various experimental methods that a single layer graphene is formed as a consequence of the intercalation of Cu atoms between the ZLG and the SiC substrate. A honeycomb lattice corresponding to the graphene with a moiré pattern is observed by scanning tunneling microscopy. A specific linear dispersion at the K point and a characteristic peak in the C1s core level spectrum, which is originated from a free-standing graphene, are demonstrated by angle-resolved photoemission spectroscopy and X-ray photoemission spectroscopy, respectively.