Abstract: Zirconium nitride thin films were deposited on SiO₂/Si(111) substrates by direct current(DC) reactive magnetron sputtering of a zirconium target with different nitrogen ratio(5%, 10%, 20%, 30%, 40%, 50%, 60%). The structure, morphology and composition of films were determined by XRD, SEM and EDS analysis. The reflection spectrum of the films was obtained by using a spectrophotometer, and the coordinates of L^*a^*b^* chromaticity were further determined. The effect of nitrogen partial pressure on the color of ZrN films and the relationship between the color and the composition and structure of ZrN films were studied. The experimental results show that all films are compact and homogeneous with increasement of nitrogen ratio. While the deposition rate decreased, the nitrogen content of the ZrN films increased, the crystallinity of the films increased first and then decreased, and the preferred(111) orientation of the films appeared with the nitrogen ratio of 10%. The film color changed significantly with the changing of the composition and structure of the films(from light gold to gold, dark gold, dark brown and non-intrinsic color). When the reaction gas N₂ is low, the zirconium and nitrogen atoms bonded easily with the increasing of nitrogen ratio. Naturally, the content of N in the films increased, and the crystallinity of ZrN increased and the preferred orientation appeared. When the nitrogen ratio over 10%, the excess nitrogen atoms in the interstitial positions of crystal makes the lattice distance larger and the crystallinity decreased. The film color also changed with the changing of composition and structure of the films.

Key words: zirconium nitride, magnetron sputtering, composition and structure, chroma