Spectral evidence of spinodal decomposition, phase transformation and molecular nitrogen formation in supersaturated TiAlN films upon annealing
2011 (English)In: Acta Materialia, ISSN 1359-6454, E-ISSN 1873-2453, Vol. 59, no 16, 6287-6296 p.Article in journal (Refereed) Published
Thermal treatment of supersaturated Ti(1-x)Al(x)N films (x approximate to 0.67) with a dominant ternary cubic-phase were performed in the 700-1000 degrees C range. Grazing incidence X-ray diffraction (GIXRD) shows that, for annealing temperatures up to 800 degrees C, the film structure undergoes the formation of coherent cubic AlN (c-AlN) and TiN (c-TiN) nanocrystallites via spinodal decomposition and, at higher temperatures (>= 900 degrees C), GIXRD shows that the c-AlN phase transforms into the thermodynamically more stable hexagonal AIN (h-AlN). X-ray absorption near-edge structure (XANES) at the Ti K-edge is consistent with spinodal decomposition taking place at 800 degrees C, while Al K-edge and N K-edge XANES and X-ray emission data show the nucleation of the h-AlN phase at temperatures >800 degrees C, in agreement with the two-step decomposition process for rock-salt structured TiAlN, which was also supported by X-ray diffraction patterns and first-principle calculations. Further, the resonant inelastic X-ray scattering technique near the N K-edge revealed that N(2) is formed as a consequence of the phase transformation process.
Place, publisher, year, edition, pages
2011. Vol. 59, no 16, 6287-6296 p.
TiAlN, Nanocrystalline materials, X-ray absorption near-edge structure, Resonant inelastic X-ray scattering
Physical Sciences Engineering and Technology
Research subject Engineering Science with specialization in Electronics
IdentifiersURN: urn:nbn:se:uu:diva-159476DOI: 10.1016/j.actamat.2011.06.039ISI: 000294936600009OAI: oai:DiVA.org:uu-159476DiVA: diva2:445395