title: Composition-dependent structure of polycrystalline magnetron-sputtered V-Al-C-N hard coatings studied by XRD, XPS, XANES and EXAFS.
abstract: V-Al-C-N hard coatings with high carbon content were deposited by reactive radio-frequency magnetron sputtering using an experimental combinatorial approach, deposition from a segmented sputter target. The composition-dependent coexisting phases within the coating were analysed using the complementary methods of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), X-ray absorption near-edge spectroscopy (XANES) and extended X-ray absorption fine-structure spectroscopy (EXAFS). For the analysis of the X-ray absorption near-edge spectra, a new approach for evaluation of the pre-edge peak was developed, taking into account the self-absorption effects in thin films. Within the studied composition range, a mixed face-centred cubic (V,Al)(C,N) phase coexisting with a C-C-containing phase was observed. No indication of hexagonal (V,Al)(N,C) was found. The example of V-Al-C-N demonstrates how important a combination of complementary methods is for the detection of coexisting phases in complex multi-element coatings.
authors.affiliation: Institut für Photonenforschung und Synchrotronstrahlung (IPS), Karlsruher Institut für Technologie, Karlsruhe, Germany.
authors.forename: Bärbel
authors.initials: B
authors.lastname: Krause
authors.forename: Susan
authors.initials: S
authors.lastname: Darma
authors.forename: Marthe
authors.initials: M
authors.lastname: Kaufholz
authors.forename: Stefan
authors.initials: S
authors.lastname: Mangold
authors.forename: Stephen
authors.initials: S
authors.lastname: Doyle
authors.forename: Sven
authors.initials: S
authors.lastname: Ulrich
authors.forename: Harald
authors.initials: H
authors.lastname: Leiste
authors.forename: Michael
authors.initials: M
authors.lastname: Stüber
authors.forename: Tilo
authors.initials: T
authors.lastname: Baumbach
keywords: X-ray absorption near-edge spectroscopy (XANES); X-ray photoelectron spectroscopy (XPS); amorphous carbon; carbides; extended X-ray absorption fine-structure spectroscopy (EXAFS); hard coatings; metastable phases; nitrides; sputter deposition
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