DIRECT GRAPHENE GROWTH ON MGO (111) BY PHYSICAL VAPOR DEPOSITION: INTERFACIAL CHEMISTRY AND BAND GAP FORMATION

摘要

Graphene can be grown directly on MgO(111) by industrially practical and scalable methods: free radical-assisted chemical vapor deposition (CVD), and physical vapor deposition (PVD). Single layer and double layer films can be produced by PVD, with a ~ 2 monolayer thick film as the apparent limiting thickness. C(1s) x-ray photoemission spectra (XPS) indicate that in both layers, carbon atoms are in two different oxidation states. A band gap of - 0.5 -1 eV has been observed for the two layer film. The XPS, LEED and band gap findings indicate that the graphene/MgO interface is commensurate, and that the MgO surface layer is reconstructed, resulting in carbon-MgO charge transfer. The ability to grow MgO(111) films on Si(100) or Si(111)- reported in the literature- points to a direct path to the development of graphene-based field effect transistors (FETs) and spin-FETs on MgO(111)/Si(100).