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Surface Diffusion Directed Growth of Anisotropic Graphene Domains on Different Copper Lattices.

ABSTRACT: Anisotropic graphene domains are of significant interest since the electronic properties of pristine graphene strongly depend on its size, shape, and edge structures. In this work, considering that the growth of graphene domains is governable by the dynamics of the graphene-substrate interface during growth, we investigated the shape and defects of graphene domains grown on copper lattices with different indices by chemical vapor deposition of methane at either low pressure or atmospheric pressure. Computational modeling identified that the crystallographic orientation of copper strongly influences the shape of the graphene at low pressure, yet does not play a critical role at atmospheric pressure. Moreover, the defects that have been previously observed in the center of four-lobed graphene domains grown under low pressure conditions were demonstrated for the first time to be caused by a lattice mismatch between graphene and the copper substrate.

SUBMITTER: Jung DH

PROVIDER: S-EPMC4756662 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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Surface Diffusion Directed Growth of Anisotropic Graphene Domains on Different Copper Lattices.

Jung Da Hee DH Kang Cheong C Nam Ji Eun JE Jeong Heekyung H Lee Jin Seok JS

Scientific reports 20160217

Anisotropic graphene domains are of significant interest since the electronic properties of pristine graphene strongly depend on its size, shape, and edge structures. In this work, considering that the growth of graphene domains is governable by the dynamics of the graphene-substrate interface during growth, we investigated the shape and defects of graphene domains grown on copper lattices with different indices by chemical vapor deposition of methane at either low pressure or atmospheric pressu ...[more]

PMID: 26883174

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