X-ray diffractometry analysis of rf-magnetron-sputtered chromium chromium nitride coatings

The effect of nitrogen content on the microstructure of chromium-based coatings deposited by r.f. magnetron sputtering was studied using various X-ray diffraction techniques. Cr, Cr2N and CrN were the major phases identified, respectively, for 5, 34 and 50 at.% by recording 8/28 and glancing incidence (1 degrees) scans. Between these well- identified crystallographic structures, we have noted a peak broadening with poor intensities that could be interpreted as mixtures of Cr, Cr2N and/or Cr(N) phases. The influence of nitrogen on the preferred crystal orientation of the films was investigated. Highly textured Cr(110) and CrN (111) were evidenced, and texture was found to be a function of nitrogen content in the sputtering atmosphere. Finally, the Langford method was applied for line profile analyses leading to results concerning crystallite sizes and strains. (C) 1998 Published by Elsevier Science S.A. All rights reserved.