Structure and chemical bonds in reactively sputtered black Ti–C–N–O thin films

• Published in: Thin solid films 2011-10, Vol.520 (1), p.144-151
• Main Authors: Chappé, J.M., Marco de Lucas, M.C., Cunha, L., Moura, C., Pierson, J.F., Imhoff, L., Heintz, O., Potin, V., Bourgeois, S., Vaz, F.
• Format: Article
• Language: English
• Subjects: Carbon; Chemical bonds; Composition and phase identification; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Deposition by sputtering; Evolution; Exact sciences and technology; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Nanomaterials; Nanoscale materials and structures: fabrication and characterization; Nanostructure; Other topics in nanoscale materials and structures; Partial pressure; Physics; Raman Spectroscopy; Reactive Sputtering; Structure and morphology; thickness; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology; Thin films; Titanium; Titanium Oxy-Carbo-Nitrides; Transmission Electron Microscopy; X-ray Photoelectron Spectroscopy
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2011.06.108

The evolution of the nanoscale structure and the chemical bonds formed in Ti–C–N–O films grown by reactive sputtering were studied as a function of the composition of the reactive atmosphere by increasing the partial pressure of an O 2 + N 2 gas mixture from 0 up to 0.4 Pa, while that of acetylene (carbon source) was constant. The amorphisation of the films observed by transmission electron microscopy was confirmed by micro-Raman spectroscopy, but it was not the only effect associated to the increase of the O 2 + N 2 partial pressure. The chemical environment of titanium and carbon, analysed by X-ray photoemission spectroscopy, also changes due to the higher affinity of Ti towards oxygen and nitrogen than to carbon. This gives rise to the appearance of amorphous carbon coexisting with poorly crystallized titanium oxynitride. The evolution of the films colour is explained on the basis of these structural changes.