Titanium Zirconium Nitride Research Articles

Ceramic nanocomposites prepared via the in situ formation of a novel TiZrN2 nanophase in a polymer-derived Si3N4 matrix

The first demonstration of a nanoscaled titanium zirconium nitride (TiZrN2) single-phase isolated during the preparation of polymer-derived silicon nitride (Si3N4) matrix nanocomposites is discussed. We employed a polysilazane, which was chemically modified with Zr[N(CH2CH3)2]4 and Ti[N(CH3)2]4 then ammonolyzed before a pyrolysis step under ammonia (1000 °C) and a heat-treatment in flowing nitrogen (1000–1700 °C). Based on a careful control of the precursor chemistry in the early stage of the process and nano-/microstructural investigations of the material performed during its preparation, we were able to identify TiZrN2 nanocrystals with a size as low as 9 nm distributed in α- and β-Si3N4 phases at a temperature as low as 1500 °C. We particularly proved that the TiZrN2 nanophase could be generated because of the use of the polysilazane evoluting towards a covalently-bonded Si3N4 matrix . This unique nanostructure is expected to provide particular functionality to Si3N4 as noble metal-free catalysts and components with high plasmonic quality.

Oblique angle deposition of nanocolumnar TiZrN films via reactive magnetron co-sputtering technique: The influence of the Zr target powers

Nanocolumnar titanium zirconium nitride (TiZrN) films deposited on silicon wafer substrates were fabricated via reactive magnetron co-sputtering with oblique angle deposition (OAD) at room temperature. The influences of the sputtering power of Zr target varied from 100 to 300 W, on the structure, morphology and composition of the nanocolumnar TiZrN film were investigated by gracing-incidence X-ray diffraction (GIXRD), field emission scanning electron microscope (FE-SEM), transmission electron microscope (TEM), energy dispersive X-ray spectroscopy (EDS), atomic force microscope (AFM) and photoelectron spectroscopy (PES). The GIXRD patterns revealed that the prepared films deposited at different sputtering powers of Zr target were crystalline in cubic phase with preferential orientation (111) and (222) planes of ZrN and TiN, respectively. The morphology obtained from FE-SEM showed well aligned slanted nanocolumnar structure, which come from the OAD technique. Increasing the sputtering power of Zr target, led to high adatom energy and enhanced collision effect during film deposition which the nanocolumnar showed obvious change in the diameter, length and tilt angle. The EDS mapping inside the nanocolumnar confirmed the homogeneity of the Ti, Zr and N element distributed in the nanocolumnar TiZrN films. Finally, the tribology behavior was preliminarily investigated based on the hardness of the nanocolumnar film and discussed in this manuscript.

Antimicrobial activity of Ti-ZrN/Ag coatings for use in biomaterial applications

Severely broken bones often require external bone fixation pins to provide support but they can become infected. In order to reduce such infections, novel solutions are required. Titanium zirconium nitride (Ti-ZrN) and Ti-ZrN silver (Ti-ZrN/Ag) coatings were deposited onto stainless steel. Surface microtopography demonstrated that on the silver containing surfaces, Sa and Sv values demonstrated similar trends whilst the Ra, average height and RMS value and Sp values increased with increasing silver concentration. On the Ti-ZrN/Ag coatings, surface hydrophobicity followed the same trend as the Sa and Sv values. An increase in dead Staphylococcus aureus and Staphylococcus epidermidis cells was observed on the coatings with a higher silver concentration. Using CTC staining, a significant increase in S. aureus respiration on the silver containing surfaces was observed in comparison to the stainless steel control whilst against S. epidermidis, no significant difference in viable cells was observed across the surfaces. Cytotoxicity testing revealed that the TiZrN coatings, both with and without varying silver concentrations, did not possess a detrimental effect to a human monocyte cell line U937. This work demonstrated that such coatings have the potential to reduce the viability of bacteria that result in pin tract infections.

Microstructure, residual stress and hardness study of nanocrystalline titanium–zirconium nitride thin films

The pulsed cathodic arc deposition technique was used to synthesize titanium–zirconium nitride (TiZrN) thin films at different substrate temperatures. A microstructural analysis extracted from the X-ray powder diffraction pattern was performed to identify the dependence of crystallite size and microstrain on TS. The residual stress state was also determined with the X-ray powder diffraction pattern assuming that the material behaved isotropically based on Young׳s modulus and the Poisson coefficient. The morphological analysis used atomic force microscopy to determine the grain size evolution with substrate temperature during deposition. The nanohardness values were obtained using nanoindentation measurements. Finally, the synthesis–property relationships were obtained with the microstructural information.

Chemical and morphological properties of (Ti–Zr)N thin films grown in an arc pulsed system

Due to its extensive field of application in different areas, including mechanics, electronics, tribology and optics the last decade has seen a large interest the study of titanium–zirconium–nitride (Ti–Zr)N thin films grown by different techniques. We had produced (Ti–Zr)N thin films and in this work chemical, morphological and electronics analysis are presented. Thin films were produced by the PAPVD (plasma assisted physics vapor deposition) technique, by pulsed arc in a mono-vaporizer system using a titanium–zirconium target with 99.99% purity. Argon–nitrogen mixture for the discharge was used. For the analyses X-ray photoelectron spectroscopy (XPS) and scanning probe microscopy (SPM) techniques were used, XPS results shown the chemical composition of the films. Films were morphologically and tribologically characterized using SPM, obtaining grain size and friction coefficient.

The evolution of diffusion barriers in copper metallization

Refractory metal nitride thin films have been widely developed as the diffusion barriers for the aluminum or copper interconnects in integrated circuits. This study reviewed the evolution of diffusion barriers in copper metallization. First, materials characteristics and electrical properties of various diffusion barriers, titanium nitride (TiN), tantalum nitride (TaN), and titanium zirconium nitride (TiZrN), were examined. These diffusion barriers were prepared by reactive magnetron sputtering in N2/Ar gas mixtures. Next, barrier performance was evaluated by annealing the Cu/barrier/Si systems at 400–1,000°C for 60 min. in vacuum as well as the measurements of copper diffusion coefficients. The results suggest that TiZrN films can be used as a diffusion barrier for copper metallization better than the well-known TaN films. Therefore, the evolution of diffusion barriers in copper metallization, from TiN to TaN and then from TaN to TiZrN, is addressed.

Growth of (Ti,Zr)N Films on Si by DC Reactive Sputtering of TiZr in N 2 / Ar Gas Mixtures: Effect of Flow Ratio

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 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 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 μΩ cm was obtained at an flow ratio of 2.75, corresponding to near stoichiometric film composition and crystalline structure. © 2004 The Electrochemical Society. All rights reserved.

Titanium Zirconium Nitride by XPS

Titanium zirconium nitride (Ti0.53Zr0.47N) coatings have been deposited on polished steel substrates by dc reactive sputtering in a Sputron (Balzers AG) plasma-beam sputtering apparatus at 200 °C. A thin intermediate layer of TiZr (0.08 μm) was deposited between the substrate and the 2.8 μm thick TiZrN coating. The deposition rate was 12 nm min−1. The partial pressure of nitrogen was 3 × 10−2 Pa, while the total working pressure was 2 × 10−1 Pa. Using a planetary substrate holder with double rotation, thickness and composition uniformity better than 2% were obtained. The average roughness, Ra, of the substrate was <0.04 μm, whereas after the deposition Ra values between 0.06 and 0.08 μm were measured for TiZrN coatings. The XPS measurements were performed in an Escalab 200-X spectrometer (VG Instruments) using nonmonochromatized Al Kα radiation from a twin Mg/Al anode operating at 300 W. The hemispherical energy analyzer was operated in the CAE mode with a constant pass energy of 20 eV. In the present paper the following spectra are presented: survey spectrum, spectra of major elements titanium, zirconium, and nitrogen (Ti 2p, Zr 3d, and N 1s), spectra of minor elements oxygen and carbon (O 1s and C 1s), and valence band spectrum. Spectra were background subtracted using a Shirley method. Peak positions and widths were determined by least squares fitting.