Growth of (Ti,Zr)N Films on Si by DC Reactive Sputtering of TiZr in N[sub 2]/Ar Gas Mixtures

Titanium zirconium nitride [(Ti, Zr)N] films were prepared on Si substrates by dc reactive magnetron sputtering from a Ti-5 atom % Zr alloy target in N-2/Ar gas mixtures. Material characteristics of the (Ti, Zr)N films were investigated by X-ray photoelectron spectroscopy, four-point probe, X-ray diffraction, atomic force microscopy, and cross-sectional transmission electron microscopy. According to those results, the deposition rate, chemical composition, crystalline structure, and film resistivity of the deposited films correlate with the N-2/Ar flow ratio. The microstructure of the (Ti, Zr)N films was an assembly of very small columnar crystallites with a rock-salt (NaCl) structure and an enlarged lattice constant (over pure TiN). A minimum film resistivity of 59.3 muOmega cm was obtained at an N-2/Ar flow ratio of 2.75, corresponding to near stoichiometric film composition [N/(Ti, Zr) = 0.96] and crystalline structure. (C) 2004 The Electrochemical Society.