The effects of encapsulating graphene with poly(methyl methacrylate) (PMMA) polymer are determined through in situ electrical transport measurements. After regenerating graphene devices in dry-nitrogen environments, PMMA is applied to their surfaces. Low-temperature annealing decreases the overall doping level, suggesting that residual solvent plays an important role in the doping. For few-layer graphene devices, we even observe stable n-doping through annealing. Application of solvent onto encapsulated devices demonstrates enhanced hysteric switching between p and n-doped states. The stability and ubiquitous use of PMMA in nanolithography make this polymer a potentially useful localized doping agent for graphene and other two-dimensional materials.
|Journal||Applied Physics Letters|
|State||Published - Dec 16 2013|
Bibliographical noteFunding Information:
We acknowledge useful discussions with J. W. Brill and J. Todd Hastings. The work was supported in part by the National Science Foundation (NSF) through Grant No. DMR-0805136, the Kentucky NSF EPSCoR program through Award No. EPS-0814194, the University of Kentucky (UK) Center for Advanced Materials (CAM), a grant from the Kentucky Science and Engineering Foundation as per Grant/Award Agreement No. KSEF-2928-RDE-016 with the Kentucky Science and Technology Corporation, and a Research Support Grant from the University of Kentucky Office of the Vice President for Research.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)