Epitaxial (111) films of Cu, Ni, and Cu{sub x}Ni{sub y} on {alpha}-Al{sub 2}O{sub 3} (0001) for graphene growth by chemical vapor deposition

Journal Article · Sat Sep 15 04:00:00 EDT 2012 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4754013· OSTI ID:22089462

Miller, David L.; Keller, Mark W.; Shaw, Justin M.; Chiaramonti, Ann N.; Keller, Robert R. ^[1]

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1. National Institute of Standards and Technology, Boulder, Colorado 80305 (United States)

Films of (111)-textured Cu, Ni, and Cu{sub x}Ni{sub y} were evaluated as substrates for chemical vapor deposition of graphene. A metal thickness of 400 nm to 700 nm was sputtered onto a substrate of {alpha}-Al{sub 2}O{sub 3}(0001) at temperatures of 250 Degree-Sign C to 650 Degree-Sign C. The films were then annealed at 1000 Degree-Sign C in a tube furnace. X-ray and electron backscatter diffraction measurements showed all films have (111) texture but have grains with in-plane orientations differing by 60 Degree-Sign . The in-plane epitaxial relationship for all films was [110]{sub metal}||[1010]{sub Al{sub 2O{sub 3}}}. Reactive sputtering of Al in O{sub 2} before metal deposition resulted in a single in-plane orientation over 97% of the Ni film but had no significant effect on the Cu grain structure. Transmission electron microscopy showed a clean Ni/Al{sub 2}O{sub 3} interface, confirmed the epitaxial relationship, and showed that formation of the 60 Degree-Sign twin grains was associated with features on the Al{sub 2}O{sub 3} surface. Increasing total pressure and Cu vapor pressure during annealing decreased the roughness of Cu and Cu{sub x}Ni{sub y} films. Graphene grown on the Ni(111) films was more uniform than that grown on polycrystalline Ni/SiO{sub 2} films, but still showed thickness variations on a much smaller length scale than the distance between grains.

• OSTI ID: 22089462
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 6 Vol. 112; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
77 NANOSCIENCE AND NANOTECHNOLOGY
ALUMINIUM OXIDES
ANNEALING
BACKSCATTERING
CHEMICAL VAPOR DEPOSITION
COPPER
COPPER ALLOYS
ELECTRON DIFFRACTION
FILMS
GRAPHENE
LAYERS
NICKEL
NICKEL ALLOYS
SILICON OXIDES
SUBSTRATES
SURFACES
TEMPERATURE RANGE 0400-1000 K
TRANSMISSION ELECTRON MICROSCOPY
X RADIATION
X-RAY DIFFRACTION