THERMAL RELIEF OF STRESSES IN SPUTTERED REFRACTORY-METALS AND COMPOUNDS

The compressive stresses in sputtered films produced with ion bombardment can be very high, increasing hardness, bending substrates, and causing adhesion failure. The thermal relief of the lattice strains produced by these stresses in chromium, molybdenum and TiN films made with bombardment from unbalanced magnetrons was studied using X-ray diffraction in films deposited at various temperatures. Significant thermal stress relief was observed during deposition for all materials, even at quite low temperatures. The lattice strain data for chromium and molybdenum were observed to overlay one another upon plotting against deposition temperature normalized by the melting temperature. The results for TiN show significant stress relief in (111) oriented crystallites, and small stresses in (200) oriented crystallites.