• 文献标题:   Regulating Top-Surface Multilayer/Single-Crystal Graphene Growth by "Gettering" Carbon Diffusion at Backside of the Copper Foil
  • 文献类型:   Article
  • 作  者:   ABIDI IH, LIU YY, PAN J, TYAGI A, ZHUANG MH, ZHANG QC, CAGANG AA, WENG LT, SHENG P, GODDARD WA, LUO ZT
  • 作者关键词:   carbon gettering, cvd graphene, multilayer, nucleation, single crystal
  • 出版物名称:   ADVANCED FUNCTIONAL MATERIALS
  • ISSN:   1616-301X EI 1616-3028
  • 通讯作者地址:   Hong Kong Univ Sci Technol
  • 被引频次:   20
  • DOI:   10.1002/adfm.201700121
  • 出版年:   2017

▎ 摘  要

A unique strategy is reported to constrain the nucleation centers for multilayer graphene (MLG) and, later, single-crystal graphene domains by gettering carbon source on backside of the flat Cu foil, during chemical vapor deposition. Hitherto, for a flat Cu foil, the top-surface-based growth mechanism is emphasized, while overlooking the graphene on the backside. However, the systematic experimental findings indicate a strong correlation between the backside graphene and the nucleation centers on the top-surface, governed by the carbon diffusion through the bulk Cu. This understanding steers to devise a strategy to mitigate the carbon diffusion to the top-surface by using a carbon "getter" substrate, such as nickel, on the backside of the Cu foil. Depth profiling of the nickel substrate, along with the density functional theory calculations, verifies the gettering role of the nickel support. The implementation of the backside carbon gettering approach on single-crystal graphene growth results in lowering the nucleation density by two orders of magnitude. This enables the single-crystal domains to grow by 6 mm laterally on the untreated Cu foil. Finally, the growth of large-area polycrystalline single layer graphene, free of unwanted MLG domains, with significantly improved field-effect mobility of approximate to 6800 cm(2) V-1 s(-1) is demonstrated.