New X-ray insight into oxygen intercalation in epitaxial graphene grown on 4H-SiC(0001)

Journal Article · Sat Mar 14 00:00:00 EDT 2015 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4914161· OSTI ID:22399270

Tokarczyk, M. ^[1]; Dąbrowski, P.; Ciepielewski, P.; Możdżonek, M.; Strupiński, W. ^[2]; Baranowski, J. M. ^[1]

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1. Faculty of Physics, University of Warsaw, Hoża 69, 00-681 Warsaw (Poland)
2. Institute of Electronic Materials Technology, Wólczyńska 133, 01-919 Warsaw (Poland)

Efficient control of intercalation of epitaxial graphene by specific elements is a way to change properties of the graphene. Results of several experimental techniques, such as X-ray photoelectron spectroscopy, micro-Raman mapping, reflectivity, attenuated total reflection, X-ray diffraction, and X-ray reflectometry, gave a new insight into the intercalation of oxygen in the epitaxial graphene grown on 4H-SiC(0001). These results confirmed that oxygen intercalation decouples the graphene buffer layer from the 4H-SiC surface and converts it into the graphene layer. However, in contrast to the hydrogen intercalation, oxygen does not intercalate between carbon planes (in the case of few layer graphene) and the interlayer spacing stays constant at the level of 3.35–3.32 Å. Moreover, X-ray reflectometry showed the presence of an oxide layer having the thickness of about 0.8 Å underneath the graphene layers. Apart from the formation of the nonuniform thin oxide layer, generation of defects in graphene caused by oxygen was also evidenced. Last but not least, water islands underneath defected graphene regions in both intercalated and non-intercalated samples were most probably revealed. These water islands are formed in the case of all the samples stored under ambient laboratory conditions. Water islands can be removed from underneath the few layer graphene stacks by relevant thermal treatment or by UV illumination.

• OSTI ID: 22399270
• Journal Information: Journal of Applied Physics, Vol. 117, Issue 10; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CLATHRATES
CRYSTAL GROWTH
CRYSTAL STRUCTURE
EPITAXY
GRAPHENE
HEAT TREATMENTS
LAYERS
MAPPING
OXIDES
OXYGEN
RAMAN SPECTROSCOPY
REFLECTIVITY
SILICON CARBIDES
SPECTRAL REFLECTANCE
SURFACES
X-RAY DIFFRACTION
X-RAY PHOTOELECTRON SPECTROSCOPY