Influence of Cu metal on the domain structure and carrier mobility in single-layer graphene

• Published in: Carbon (New York) Vol. 50; no. 6; pp. 2189 - 2196
• Main Authors: Orofeo, Carlo M., Hibino, Hiroki, Kawahara, Kenji, Ogawa, Yui, Tsuji, Masaharu, Ikeda, Ken-ichi, Mizuno, Seigi, Ago, Hiroki
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.05.2012; Elsevier
• Subjects: Boundaries; Carbon; Carrier mobility; Catalysis; Chemical vapor deposition; Chemistry; Copper; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Foils (structural shapes); Fullerenes and related materials; diamonds, graphite; General and physical chemistry; Graphene; Low energy; Materials science; Physics; Specific materials; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Epitaxial layers; Catalysts; Films; Crystals; Mobility; Foils; Crystallinity; Electron microscopy; Orientation; Plane structure; CVD; Energy; Domain structure
• ISSN: 0008-6223; 1873-3891
• DOI: 10.1016/j.carbon.2012.01.030

We demonstrate that domain structure of single-layer graphene grown by ambient pressure chemical vapor deposition is strongly dependent on the crystallinity of the Cu catalyst. Low energy electron microscopy analysis reveals that graphene grown using a Cu foil gives small and mis-oriented graphene domains with a number of domain boundaries. On the other hand, no apparent domain boundaries are observed in graphene grown over a heteroepitaxial Cu(111) film deposited on sapphire due to unified orientation of graphene hexagons. The difference in the domain structures is correlated with the difference in the crystal plane and grain structure of the Cu metal. The graphene film grown on the heteroepitaxial Cu film exhibits much higher carrier mobility than that grown on the Cu foil.