6533b7d4fe1ef96bd126204f

RESEARCH PRODUCT

Substrate and atmosphere influence on oxygen p-doped graphene

Franco Mario GelardiMichelangelo ScopellitiAntonino La MagnaGabriele FisichellaFabrizio RoccaforteFilippo GiannazzoSimonpietro AgnelloMarco CannasGianpiero BuscarinoAurora PiazzaAurora PiazzaBruno Pignataro

subject

Materials sciencegenetic structuresSettore FIS/01 - Fisica SperimentaleDopingAnalytical chemistrychemistry.chemical_element02 engineering and technologyGeneral ChemistrySubstrate (electronics)Dielectric010402 general chemistry021001 nanoscience & nanotechnology01 natural sciencesNitrogenOxygenGraphene doping substrate effects thermal effects Raman Spectroscopy0104 chemical sciencesp-type doped grapheneX-ray photoelectron spectroscopychemistryoxygen annealingGeneral Materials ScienceThin film0210 nano-technologySpectroscopy

description

Abstract The mechanisms responsible for p-type doping of substrate supported monolayer graphene (Gr) by thermal treatments in oxygen ambient have been investigated by micro-Raman spectroscopy, atomic force microscopy (AFM) and X-ray Photoelectron Spectroscopy (XPS), considering commonly employed dielectric substrates, such as SiO 2 and Al 2 O 3 thin films grown on Si. While a high p-type doping (∼10 13  cm −2 ) is observed for Gr on SiO 2 , no significant doping is found for Gr samples on the Al 2 O 3 substrate, suggesting a key role of the Gr/SiO 2 interface states in the trapping of oxygen responsible for the Gr p-type doping. Furthermore, we investigated the doping stability of Gr on SiO 2 during subsequent thermal treatments in nitrogen (N 2 ), carbon dioxide (CO 2 ), water (H 2 O) or in vacuum controlled atmospheres. These processes induce only minor effects on the doping of Gr but for H 2 O and principally affect its defectiveness, suggesting that the literature reported air influence on the doping depends on water present in the atmosphere.

yearjournalcountryeditionlanguage
2016-10-01Carbon
https://doi.org/10.1016/j.carbon.2016.06.077