Comparison of AES analyses of transition‐metal nitride coatings with carrier‐gas heat extraction analyses

In spite of some work on the quantification of Auger spectra of transition-metal nitride thin films (hard coatings), a correlation with the true nitrogen content is rather difficult. In order to get a measure of the validity of the generally applied calibration of AES results by means of Handbook relative sensitivity factors, TiNx, ZrNx, NbNx and MoNx films of different nitrogen content were deposited by reactive magnetron sputtering on thin high-purity platinum foils and were analysed subsequently for their nitrogen content by carrier-gas heat extraction analysis (GA). The GA results were compared with the above-mentioned AES evaluation. Whereas the agreement between GA and AES is fairly good for TiNx (based on a special AES evaluation procedure), it depends significantly on the use of either high- or low-energy Auger peaks for Zr, Nb and Mo. Corrections of AES elemental sensitivity factors for changes in density, Auger electron escape depth and primary electron back-scattering only show a minor influence in the direction of higher nitrogen contents. Comparison of GA and AES results yields sensitivity correction factors for the used metal peak energies in the systems studied.