Dopant Segregation in Polycrystalline Monolayer Graphene
journal contributionposted on 11.02.2015, 00:00 by Liuyan Zhao, Rui He, Amir Zabet-Khosousi, Keun Soo Kim, Theanne Schiros, Michael Roth, Philip Kim, George W. Flynn, Aron Pinczuk, Abhay N. Pasupathy
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.