Graphene epitaxially grown on vicinal 4H-SiC (0001) substrates

Abstract

The growth mode of graphene epitaxially grown on vicinal SiC(OOOl) substrates as well as on-axis SiC(OOOl) surface has been investigated by scanning tunneling microscopy and low energy electron diffraction. The results show that the graphene favors to start to emerge from the edge of the surface steps, forming narrow graphene domains at the step edges on the vicinal surface with 4° off-axis angle, well separated by carbon rich (6√× 6√) domains, suggesting the possibility of obtaining graphene nano-ribbons. The graphene film grown on vicinal surface with larger off-axis angle (21°) shows a wave-like morphology, exhibiting the continuity of graphene film across the step edges. © 2009 The Surface Science Society of Japan.