title: Semi-quantitative chemical analysis of hard coatings by Raman micro-spectroscopy: the aluminium chromium nitride system as an example.
abstract: A new method for chemical analyses of nitride-based hard coatings is presented. Raman band shifts in the spectra of Al(x)Cr(1-x)N coatings, deposited by physical vapour deposition from Al(x)Cr(1-x) targets with x (T,Al) = 0, 0.25, 0.50, 0.70 and 0.85, are calibrated using compositional data of the coatings derived by elastic recoil detection analysis (ERDA) and electron probe micro-analysis (EPMA). Inserting the composition-dependent Raman shift of a combinatorial acoustic-optic lattice mode into an empirically derived equation allows the determination of Al/Cr ratios of the coating with an accuracy of about +/-2%. Spot, line and area analyses of coated cemented carbide and cold work steel samples by using a computer-controlled, motorized x,y-stage are demonstrated and the most important errors influencing precision and accuracy are discussed. Figure Raman map of a coated cold-work steel sample.
authors.affiliation: Institute of Mineralogy and Petrography, University Innsbruck, Innrain 52, 6020 Innsbruck, Austria. reinhard.kaindl@uibk.ac.at
authors.forename: R
authors.initials: R
authors.lastname: Kaindl
authors.forename: B
authors.initials: B
authors.lastname: Sartory
authors.forename: J
authors.initials: J
authors.lastname: Neidhardt
authors.forename: R
authors.initials: R
authors.lastname: Franz
authors.forename: A
authors.initials: A
authors.lastname: Reiter
authors.forename: P
authors.initials: P
authors.lastname: Polcik
authors.forename: R
authors.initials: R
authors.lastname: Tessadri
authors.forename: C
authors.initials: C
authors.lastname: Mitterer