X-RAY RESIDUAL-STRESS MEASUREMENT IN TIN, ZRN AND HFN FILMS USING THE SEEMANN-BOHLIN METHOD

The equation for the effect of stress on the lattice parameters returned by the Seemann-Bohlin fine focus goniometer is generalized for cubic crystals to include the effect of the X-ray elastic constants (XECs) of the individual crystal planes. Using the equation, the analysis of data taken from some group IVB nitride films, TiN, ZrN and HfN, indicates that the residual stress derived when taking the XECs into account can be higher by as much as 20% in the case of ZrN. The analysis also returned values for the bulk Poisson's ratio for all the films which are in good agreement with an earlier study. The study appears to indicate that the grazing angle of incidence in the Seemann-Bohlin method should not be set too low or the results can be affected by the native oxygen-containing layer on the sample surface.