title: Dopant segregation in polycrystalline monolayer graphene.
abstract: Heterogeneity in dopant concentration has long been important to the electronic properties in chemically doped materials. In this work, we experimentally demonstrate that during the chemical vapor deposition process, in contrast to three-dimensional polycrystals, the substitutional nitrogen atoms avoid crystal grain boundaries and edges over micron length scales while distributing uniformly in the interior of each grain. This phenomenon is universally observed independent of the details of the growth procedure such as temperature, pressure, substrate, and growth precursor.
authors.affiliation: Department of Physics, Columbia University , New York, New York 10027, United States.
authors.forename: Liuyan
authors.initials: L
authors.lastname: Zhao
authors.forename: Rui
authors.initials: R
authors.lastname: He
authors.forename: Amir
authors.initials: A
authors.lastname: Zabet-Khosousi
authors.forename: Keun Soo
authors.initials: KS
authors.lastname: Kim
authors.forename: Theanne
authors.initials: T
authors.lastname: Schiros
authors.forename: Michael
authors.initials: M
authors.lastname: Roth
authors.forename: Philip
authors.initials: P
authors.lastname: Kim
authors.forename: George W
authors.initials: GW
authors.lastname: Flynn
authors.forename: Aron
authors.initials: A
authors.lastname: Pinczuk
authors.forename: Abhay N
authors.initials: AN
authors.lastname: Pasupathy
keywords: Chemical vapor deposition; dopant segregation; micro-Raman spectroscopy; nitrogen-doped graphene; scanning tunneling microscopy