title: Precise Identification of Graphene's Crystal Structures by Removable Nanowire Epitaxy.
abstract: Monitoring crystallographic orientations of graphene is important for the reliable generation of graphene-based nanostructures such as van der Waals heterostructures and graphene nanoribbons because their physical properties are dependent on crystal structures. However, facile and precise identification of graphene's crystallographic orientations is still challenging because the majority of current tools rely on complex atomic-scale imaging. Here, we present an identification method for the crystal orientations and grain boundaries of graphene using the directional alignment between epitaxially grown AuCN nanowires and the underlying graphene. Because the nanowires are visible in scanning electron microscopy, crystal orientations of graphene can be inspected with simple procedures. Kernel density estimation that we used in analyzing the nanowire directions enables precise measurement of graphene's crystal orientations. We also confirm that the imaged nanowires can be simply removed without degrading graphene's quality, thus showing that the present method can be practically used for measuring graphene's crystal structures.
authors.affiliation: Department of Mechanical Engineering, Hanyang University , Ansan, Gyeonggi 15588, Republic of Korea.
authors.forename: Jonghyeok
authors.initials: J
authors.lastname: Kim
authors.affiliation: Department of Mechanical Engineering, Hanyang University , Ansan, Gyeonggi 15588, Republic of Korea.
authors.forename: Kitaek
authors.initials: K
authors.lastname: Lim
authors.affiliation: Department of Physics, Ulsan National Institute of Science and Technology (UNIST) , Ulsan 44919, Republic of Korea.
authors.forename: Yangjin
authors.initials: Y
authors.lastname: Lee
authors.affiliation: Department of Mechanical Engineering, Hanyang University , Ansan, Gyeonggi 15588, Republic of Korea.
authors.forename: Jongin
authors.initials: J
authors.lastname: Kim
authors.affiliation: Department of Mechanical Engineering, Hanyang University , Ansan, Gyeonggi 15588, Republic of Korea.
authors.forename: Kihwan
authors.initials: K
authors.lastname: Kim
authors.affiliation: School of Chemical and Biological Engineering, Seoul National University , Seoul 08826, Republic of Korea.
authors.forename: Jungwon
authors.identifier: http://orcid.org/0000-0003-2927-4331
authors.initials: J
authors.lastname: Park
authors.affiliation: Department of Physics, Ulsan National Institute of Science and Technology (UNIST) , Ulsan 44919, Republic of Korea.
authors.forename: Kwanpyo
authors.identifier: http://orcid.org/0000-0001-8497-2330
authors.initials: K
authors.lastname: Kim
authors.affiliation: Department of Mechanical Engineering, Hanyang University , Ansan, Gyeonggi 15588, Republic of Korea.
authors.forename: Won Chul
authors.identifier: http://orcid.org/0000-0001-8479-0836
authors.initials: WC
authors.lastname: Lee