title: Quasi-periodic nanoripples in graphene grown by chemical vapor deposition and its impact on charge transport.
abstract: The technical breakthrough in synthesizing graphene by chemical vapor deposition methods (CVD) has opened up enormous opportunities for large-scale device applications. To improve the electrical properties of CVD graphene grown on copper (Cu-CVD graphene), recent efforts have focused on increasing the grain size of such polycrystalline graphene films to 100 μm and larger. While an increase in grain size and, hence, a decrease of grain boundary density is expected to greatly enhance the device performance, here we show that the charge mobility and sheet resistance of Cu-CVD graphene is already limited within a single grain. We find that the current high-temperature growth and wet transfer methods of CVD graphene result in quasi-periodic nanoripple arrays (NRAs). Electron-flexural phonon scattering in such partially suspended graphene devices introduces anisotropic charge transport and sets limits to both the highest possible charge mobility and lowest possible sheet resistance values. Our findings provide guidance for further improving the CVD graphene growth and transfer process.
authors.affiliation: Department of Physics, 2 Science Drive 3, National University of Singapore, Singapore 117542.
authors.forename: Guang-Xin
authors.initials: GX
authors.lastname: Ni
authors.forename: Yi
authors.initials: Y
authors.lastname: Zheng
authors.forename: Sukang
authors.initials: S
authors.lastname: Bae
authors.forename: Hye Ri
authors.initials: HR
authors.lastname: Kim
authors.forename: Alexandre
authors.initials: A
authors.lastname: Pachoud
authors.forename: Young Soo
authors.initials: YS
authors.lastname: Kim
authors.forename: Chang-Ling
authors.initials: CL
authors.lastname: Tan
authors.forename: Danho
authors.initials: D
authors.lastname: Im
authors.forename: Jong-Hyun
authors.initials: JH
authors.lastname: Ahn
authors.forename: Byung Hee
authors.initials: BH
authors.lastname: Hong
authors.forename: Barbaros
authors.initials: B
authors.lastname: Ozyilmaz