title: In situ observation of step-edge in-plane growth of graphene in a STEM.
abstract: It is extremely difficult to control the growth orientation of the graphene layer in comparison to Si or III-V semiconductors. Here we report a direct observation of graphene growth and domain boundary formation in a scanning transmission electron microscope, with residual hydrocarbon in the microscope chamber being used as the carbon source for in-plane graphene growth at the step-edge of bilayer graphene substrate. We show that the orientation of the growth is strongly influenced by the step-edge structure and areas grown from a reconstructed 5-7 edge are rotated by 30° with respect to the mother layer. Furthermore, single heteroatoms like Si may act as catalytic active sites for the step-edge growth. The findings provide an insight into the mechanism of graphene growth and defect reconstruction that can be used to tailor carbon nanostructures with desired properties.
authors.affiliation: 1] Nanotube Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8565, Japan [2].
authors.forename: Zheng
authors.initials: Z
authors.lastname: Liu
authors.affiliation: 1] Nanotube Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8565, Japan [2].
authors.forename: Yung-Chang
authors.initials: YC
authors.lastname: Lin
authors.affiliation: Department of Electrical Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan.
authors.forename: Chun-Chieh
authors.initials: CC
authors.lastname: Lu
authors.affiliation: Department of Electrical Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan.
authors.forename: Chao-Hui
authors.initials: CH
authors.lastname: Yeh
authors.affiliation: Department of Electrical Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan.
authors.forename: Po-Wen
authors.initials: PW
authors.lastname: Chiu
authors.affiliation: Nanotube Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8565, Japan.
authors.forename: Sumio
authors.initials: S
authors.lastname: Iijima
authors.affiliation: Nanotube Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8565, Japan.
authors.forename: Kazu
authors.initials: K
authors.lastname: Suenaga