@article{Wang2013, 
author = {Zhou-jun Wang and Mingming Wei and Li Jin and Yanxiao Ning and Liang Yu and Qiang Fu and Xinhe Bao},
title = {Simultaneous N-intercalation and N-doping of epitaxial graphene on 6H-SiC(0001) through thermal reactions with ammonia},
year = {2013},
journal = {Nano Research},
volume = {6},
number = {6},
pages = {399-408},
keywords = {graphene, SiC, doping, intercalation, STM},
url = {https://www.sciopen.com/article/10.1007/s12274-013-0317-7},
doi = {10.1007/s12274-013-0317-7},
abstract = {Surface functionalization of epitaxial graphene overlayers on 6H-SiC(0001) has been attempted through thermal reactions in NH3. X-ray photoelectron spectroscopy and micro-region low energy electron diffraction results show that a significant amount of N is present at the NH3-treated graphene surface, which results in strong band bending at the SiC surface as well as decoupling of the graphene overlayers from the substrate. The majority of the surface N species can be removed by annealing in vacuum up to 850 ℃, weakening the surface band bending and resuming the strong coupling of graphene with the SiC surface. The desorbed N atoms can be attributed to the intercalated species between graphene and SiC. Low temperature scanning tunneling spectroscopy and density functional theory simulations confirm the presence of N dopants in the graphene lattice, which are in the form of graphitic substitution and can be stable above 850 ℃. This is the first report of simultaneous N intercalation and N doping of epitaxial graphene overlayers on SiC, and it may be employed to alter the surface physical and chemical properties of epitaxial graphene overlayers.}
}