AVS 60th International Symposium and Exhibition
    Graphene and Other 2D Materials Focus Topic Wednesday Sessions
       Session GR+AS+EM+NS+SS-WeA

Invited Paper GR+AS+EM+NS+SS-WeA3
Engineering Chemical Dopants in Monolayer Graphene

Wednesday, October 30, 2013, 2:40 pm, Room 104 B

Session: Dopants, Defects and Interfaces in 2D Materials
Presenter: A. Pasupathy, Columbia University
Correspondent: Click to Email
Chemical doping is a promising route to achieve control over the carrier concentration in graphene. I will describe recent experiments on the growth of graphene that is chemically doped using nitrogen and boron atoms. Using a combination of scanning tunneling microscopy, Raman and x-ray spectroscopies, we are able to obtain a picture of the chemical and electronic structure of doped graphene from the atomic to the macroscale. At the atomic scale, I will describe the local bonding of nitrogen and boron dopants and their effect on free carrier concentration in the graphene sheet. At larger length scales, I will show that nitrogen dopants avoid edges and grain boundaries of the graphene film over length scales that can be as large as a micron. I will also discuss dopant clustering and show that nitrogen and boron behave very differently in this respect. Understanding these various effects requires us to consider both the mechanism by which graphene grows by chemical vapor deposition, and the interaction between the dopant atoms and the underlying substrate during growth.