ISSN:
0142-2421
Keywords:
XPS
;
FTIR
;
carbon nitride
;
thin film
;
simulation
;
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Physics
Notes:
The chemical composition and microstructure of dual ion beam-deposited CNx films with nitrogen contents in the range 20-33 at.% have been examined by Fourier transform infrared spectroscopy (FTIR) and x-ray photoelectron spectroscopy (XPS). The FTIR spectra together with other published data have been used to construct a model microstructure of the CNx films. The XPS N 1s peak is composed of two components corresponding to N-sp2 C and N-sp3 C bonds. Using the quantified N 1s data and making certain assumptions, the model microstructure has been used as the basis of a C 1s peak simulation in which nine C components have been combined. At an N content of 20 at.% the simulation agrees well with the experimentally recorded XPS C 1s peak. The FTIR spectra, XPS N 1s peak shape and C 1s peak simulations support a chemical structure of N substitution in an amorphous sp2/sp3 hybridized carbon structure. Above an N content of ∽20%, a new (nitrile-like) chemical form also emerges in the material, its abundance increasing with N content. It is proposed that this new structure occurs due to the presence, in the surface region of the condensing film, of C—N dimers, which are formed when a C atom is surrounded by many N atoms. This molecule becomes trapped in the material and bonds to atoms at neighbouring sites. © 1997 John Wiley & Sons, Ltd.
Additional Material:
12 Ill.
Type of Medium:
Electronic Resource
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