1999 Volume 48 Issue 3Appendix Pages 45-50
The structure and residual stresses of TiN films deposited on a steel substrate were investigated by X-ray diffraction. TiN films approximately 4μm thick were deposited on one side of the substrate by thermal chemical vapor deposition (TiNCVD film). The TiNCVD film exhibited high {100} orientation. The two-exposure method was used to evaluate residual stresses in the TiN films by measuring lattice strains in the directions determined by the crystal orientation of the film. The TiNCVD films had the compressive residual stress of -1.8GPa, which is as large as the thermal residual stress expected from a thermal strain mismatch between the film and the substrate. The residual stresses did not change by annealing at temperatures below 1073K, but they increased with increasing annealing temperatures above 1073K, almost along with the thermal residual stresses. By X-ray photoelectron spectroscopy (XPS), we determined the ratio of nitrogen to titanium (N/Ti) after the annealing treatments. The results of the XPS analysis showed that the initial value of N/Ti was about 1.08 in the as-deposited TiN films and that the ratio of N/Ti did not change after annealing at temperatures below 1073K, but decreased to 1.00 after annealing at temperatures above 1073K.
