• Caridad, José M.
• Andryieuski, Andrei
• Pizzocchero, Filippo
• Tang, Peter T.
• Hone, James
• Sørensen Jessen, Bjarke
• Kling, Jens
• Malureanu, Radu
• Bøggild, Peter
• Petrone, Nicholas
• Whelan, Patrick Rebsdorf
• Gammelgaard, Lene
• Shivayogimath, Abhay
• Lavrinenko, Andrei V.
• Booth, Timothy

Abstract

<p>The purity and morphology of the copper surface is important for the synthesis of high-quality, large-grained graphene by chemical vapor deposition. We find that atomically smooth copper foils─fabricated by physical vapor deposition and subsequent electroplating of copper on silicon wafer templates─exhibit strongly reduced surface roughness after the annealing of the copper catalyst, and correspondingly lower nucleation and defect density of the graphene film, when compared to commercial cold-rolled copper foils. The "ultrafoils"─ultraflat foils─facilitate easier dry pickup and encapsulation of graphene by hexagonal boron nitride, which we believe is due to the lower roughness of the catalyst surface promoting a conformal interface and subsequent stronger van der Waals adhesion between graphene and hexagonal boron nitride.</p>

Topics

• density
• impedance spectroscopy
• morphology
• surface
• physical vapor deposition
• nitride
• copper
• Silicon
• defect
• Boron
• annealing
• chemical vapor deposition