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A two-dimensional (2D) model of infiltration-mediated combustion in a porous sample with all boundaries closed to gas penetration except for one open to exchange with a large bath of gas is considered. Numerical analysis with account of heat losses through the side surface has shown that the profile of gas pressure is substantially two-dimensional. Due to heat losses, the transversal gas flow begins to occur from a cold wall (where there is no reaction and gas consumption) to the sample center (where gas is deficient). As a result, the distribution of conversion degree over sample cross sections exhibits a maximum near the side surface, which reasonably agrees with the experimental data obtained for combustion of tantalum powder in nitrogen gas in quartz tubes. [ABSTRACT FROM AUTHOR]

Abstract: Ta–N thin films were deposited on AISI 317L stainless steel (SS) substrates by cathodic arc deposition (CAD) at substrate biases of −50 and −200V. The as-deposited films were characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray analysis (EDX). The results show that stoichiometric TaN with hexagonal lattice (300) preferred orientation was achieved at the bias of −200V. On the other hand, Ta-rich Ta–N thin film deposited at −50V shows amorphous nature. According to the XPS result, Ta element in the films surface exist in bonded state, including the Ta–N bonds characterized by the doublet (Ta 4f7/2 =23.7eV and Ta 4f5/2 =25.7eV). Electrochemical properties of the Ta–N coated stainless steel systems were investigated using potentiodynamic polarization and electrochemical impedance spectroscope (EIS) in Hank''s solution at 37°C. For the Ta–N coated samples, the corrosion current (i corr) is two or three orders of magnitude lower than that of the uncoated ones, indicating a significantly improved corrosion resistance. Growth defects in the Ta–N thin films produced by CAD, however, play a key role in the corrosion process, especially the localised corrosion. Using the polarization fitting and the EIS modelling, we compared the polarization resistance (R p) and the porosity (P) of the Ta–N coatings deposited at different biases. It seems that Ta–N film with comparatively lower bias (−50V) shows better corrosion behavior in artifical physiological solution. That may be attributed to the effect of ion bombarding, which can be modulated by the substrate bias. [Copyright &y& Elsevier]

Abstract: The evolution of the interface between organosilicate glass (OSG) and sputter deposited Ta or TaN films has been characterized by X-ray phototelectron spectroscopy (XPS). Cross-sectional TEM (XTEM) was also used to analyze Ta/OSG and TaN/OSG/interfaces for samples formed under different deposition conditions. XPS data show that Ta deposition onto OSG results in formation of an interphase between 1 and 2nm thick composed of oxidized Ta and C. Metallic Ta is then formed on top of the interfacial region. In contrast, Ta-rich TaN formation occurs with some nitridation of the substrate, but with no significant interphase formation. The XPS data are consistent with the XTEM data. The XTEM results for Ta/OSG indicate a spatially irregular interface over a length scale of ∼2nm, while results for TaN/OSG indicate a spatially abrupt region. [Copyright &y& Elsevier]

Abstract: Tantalum nitride films were deposited on silicon wafer and steel substrates by cathodic vacuum arc in N2/Ar gas mixtures. The chemical composition, crystalline microstructure and morphology of the films were investigated by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM), respectively. According to the results, film composition and microstructure depends strongly on the N2 partial pressure and the applied negative bias (V s). [Copyright &y& Elsevier]

Abstract: The effect of inductively coupled plasma (ICP) power on the mechanical properties of tantalum-nitride films was investigated. TaN films were grown on an Si (001) substrate using ICP assisted magnetron sputter deposition in a mixed Ar/N2 discharges at 20 mTorr (2.67 Pa) and 350 °C. For the structural analysis, X-ray diffraction, auger electron scanning and atomic force microscopy were used and the hardness was measured using a micro indentation tester. The structure of the TaN films changed as the ICP power (100–400 W) and nitrogen fraction f N2 (0.1–0.15) were varied. When the ICP RF power was increased from 100 to 400 W, hexagonal ε-TaN appeared in the existing compound of hexagonal γ-Ta2N (f N2 =0.1) or cubic δ-TaN (f N2 =0.125 and 0.15). When the ICP power was increased from 100 W to 400 W, the hardness also increased from 25–35 GPa to around 70 GPa. It is supposed that the significant increase in the hardness was contributed to by the dense microstructure with very small grains and also by the multi-phase structure of the film. [Copyright &y& Elsevier]

Abstract: In this paper, Fourier-transform infrared (FTIR) spectroscopy and ellipsometric spectroscopy were used to characterize the optical properties of atomic layer-deposited (ALD) ultra-thin TaN films on a Si(100) single crystal. The analysis of FTIR spectra indicates that the incorporated impurities are in the form of radicals of NH x , CH x and OH x . SiH x is also detected due to interfacial reactions between NH x and the Si substrate native oxide. These H-containing radicals can be removed by post-annealing the samples. The vibration of Ta–N bonding is at the wavenumber of 1190cm−1, which is independent of the film thickness and post-annealing temperature. The results of ellipsometric spectra show that the band gaps are 3.28eV, 2.65eV and 2.50eV as the films thicknesses are 1nm, 5nm and 10nm, respectively. A slight red-shift of the band gap takes place after annealing the ultra-thin films. The mechanisms of the film optical properties were analyzed in the paper. [Copyright &y& Elsevier]

Abstract: Transition metal nitride coatings are used in electronics industry as a diffusion barrier coating. In the present study, tantalum nitride thin films were coated at room temperature (300 K) on various substrates, such as cemented carbide milling inserts, glass and stainless steel, using pulsed DC magnetron sputtering technique. Optical emission spectroscopy (OES) was employed to analyze the sputtering plasma to understand the reaction kinetics of tantalum nitride formation. The properties of the films were evaluated by various techniques, including X-ray diffraction (XRD), scratch adhesion test, ball-and-crater method and atomic force microscopy (AFM). The deposition rate was found to increase with an increase in sputtering power. The coatings were amorphous at low sputtering power, and showed development of crystalline structure, with (111) orientation. The initial results show that the film structure and adhesion needs to be improved further for tribological applications. [Copyright &y& Elsevier]

Abstract: Seedless copper electrochemical deposition (ECD) becomes a potential interconnect technology while device dimension keeps shrinking in ULSI design. In seedless copper ECD on TaN, which is a widely used diffusion barrier, uniform growth of copper film on TaN is hindered because a robust native Ta2O5 exists on TaN surface. Complete removal of the native Ta2O5 can be attained using a saturated KOH solution that is assisted by an anodic voltage. This then permits that copper film grows on the pretreated TaN surface in a copper–citrate (Cu–Cit) complex electrolyte. Its growing morphology and deposition rate are dependent on the etching depth of as-deposited TaN in the KOH solution. Even for a very short etching time of 0.8 s, thin Ta2O5 is totally etched off and the activated TaN surface appears. Thin and conformal copper films grown in a layer-by-layer mode on the TaN surface are proper to function as an ECD seed or metal lines for ULSI interconnects. [Copyright &y& Elsevier]

Abstract: Tantalum nitride thin films were deposited on AlN substrates at room temperature with an nitrogen/argon flow ratio (N2/(N2 +Ar)) of 3% by dc-magnetron sputtering technique, and then were annealed at 525°C in 6.7×10−4 Pa. The microstructural and electrical properties of the films were investigated as a function of film thickness. The crystallinity of the films decreased with decreasing film thickness and the sheet resistance of 50nm-thick tantalum nitride films is approximately 80Ω/□ suitable for 10dB application in π-type attenuators. The TCR values increase positively with increasing the thickness and 50nm thick films exhibit a near-zero TCR value of approximately −6ppm/K. [Copyright &y& Elsevier]

Abstract: A series of samples of Ta3N5 (Cmcm, , , ) have been produced by high-temperature ammonolysis of amorphous tantalum oxide under various temperature and heating time regimes. These were characterised by powder diffraction (X-ray and neutron), combustion microanalysis, thermogravimetric analysis and transmission electron microscopy. All samples were found to contain oxide in the 3-coordinate anion site and the b-axis length was sensitive to compositional variation. Samples heated for longer times at higher temperatures were anion deficient. The compositions of the samples have been related to their optical band gap UV–visible spectra. This work highlights the importance of careful compositional analysis when samples of nitride materials are produced for real-world applications. [Copyright &y& Elsevier]

Abstract: This paper concentrates on the mechanical, the electrical, and the acoustical properties of the Ta–N films deposited by radio frequency (rf) magnetron reactive sputtering in Ar/N2 gas mixtures. As the nitrogen partial pressure increased, a microstructure transformation of the films from columnar polycrystalline to amorphous was observed, and the differences on the acoustic properties were measured by the picosecond ultrasonic technique. We also found that the electrical resistivities of TaN x films rose steeply by six orders of magnitude owing to the lack of extra nitrogen as the donors, and excess electron scattering caused by the porous structure. [Copyright &y& Elsevier]

Abstract: Atomic layer deposition (ALD) TaN films are designed as diffusion barriers for Cu metallization of silicon devices. In a previous paper, we characterized the compositions and structures of ultrathin ALD TaN films. In this study, the effects of various thermal processes on the characteristics of Cu/ALD TaN/Si stacks are investigated by various analytical techniques. The results indicate that, for the as-received Cu/ALD TaN/Si samples (G1 set samples), thermal treatment at a temperature higher than 500 °C results in formation of the intermetallic compound Cu3Si on the surface. It is interesting to note that the amount of copper silicide on the surface increases with the ALD TaN thickness, as long as the later is less than 10 nm. No Cu3Si is detected after the same thermal process in similar stacks, when the top-layer Cu was deposited on pre-annealed ALD TaN/Si samples (G2 set samples). Cu dewetting occurs after thermally treating the Cu/ALD TaN/Si stacks for both G1 set and G2 set samples. Analysis indicates that impurities play an important role on the thermal behaviors of G1 and G2 stacks. [Copyright &y& Elsevier]

The corrosion behaviour of tantalum nitride (TaN) thin films deposited on AISI 1018 carbon steel, AISI M2 tool steel and AISI 304 stainless steel has been investigated in an aqueous sodium chloride solution. The films were produced by means of magnetron sputtering plasma deposition. Morphological and microstructuctural characteristics of the films were studied by atomic force microscopy and X-ray diffraction analysis. Potentiodynamic polarisation, electrochemical impedance spectroscopy and cyclic voltammetry techniques were used for electrochemical characterisation. The TaN films displayed lower corrosion current densities than those of the substrates. A relaxation time in the impedance analysis was observed in the 1018/TaN system, two relaxation times were observed in the M2/TaN system, and a diffusion process was found in the 304/TaN system. This indicates that the substrates were not completely isolated from the solution and the defects in the films appear to be detrimental owing to electrolyte penetration through the defects which caused localised corrosion. The corrosion behaviour of the films depends mainly on the electrochemical properties of the substrate. [ABSTRACT FROM AUTHOR]

Abstract: Tantalum nitride (Ta2N) films deposited at various substrate temperatures onto silicon (001) substrates can produce amorphous and crystalline phase with different preferred orientations. Subsequently, the viability of employing them as the diffusion barriers between copper and silicon is investigated by annealing at various temperatures for 30 min. The characterization of the thin films was carried out by four-point probe and X-ray diffraction. The results indicate that the thermal stability of Ta2N with Cu and Si are dependent on the crystallinity of Ta2N. Ta2N phase with the highest (002) preferred orientation exhibits the highest structural stability to prevent copper diffusion more effectively. [Copyright &y& Elsevier]

Abstract: TaN films were deposited by reactive DC magnetron sputtering onto Si and SiO2 with thicknesses of less than one monolayer up to 10nm. After this, the samples were transferred into the analysis chamber without breaking the vacuum and analysed by means of X-ray photoelectron spectroscopy (XPS) and angular resolved XPS (ARXPS). XPS measurements as a sensitive method to characterise chemical states showed a silicon nitride formation at the interface at deposition on Si. On the SiO2 no reaction was found at the interface. Based on these observations layer models for quantification of ARXPS measurements by means of model calculations were derived, so it was possible to obtain information on the in-depth element distribution in a non-destructive manner. For comparison to the ARXPS investigations analyses of the inelastic background of the Ta4d peak are shown and discussed. [Copyright &y& Elsevier]

Abstract: Reliably acting diffusion barrier films are basically for the functionality of the copper inter-connect technology. Tantalum (Ta) and Tantalum nitride (TaN) are established materials for diffusion barriers against copper diffusion. In this study, the characterization of TaN like films produced using N+ plasma immersion ion implantation (PIII) was performed using Auger electron spectroscopy (AES). Chemical information was extracted from the Auger data using linear least square fit (LLS). The capability of the method in order to detect very little changes in the film composition dependent on small process changes was demonstrated. The nitrogen incorporation by PIII into high aspect ratio contact holes was proven using analytical TEM. [Copyright &y& Elsevier]

Abstract: Electroless (EL) deposition is used as a seeding technology for Cu metallization in the back-end-of-line semiconductor fabrication process. In this work, effect of deposition time and annealing treatment on the properties of electroless copper seed layer are reported. It is found that all seed layers exceeding 2-min deposition possess a (111) texture. The grain size, morphology and resistivity of the electroless Cu vary with deposition time. The largest grain size obtained by current work is around 70 nm. This corresponds to the lowest resistivity of 4.30 μΩ cm. The surface roughness of as-deposited Cu films ranges from 36.6 to 51.9 nm. Annealing results in the growth of copper grains and improvement in surface roughness and film conductivity. The annealing treatment does not change the existing texture. [Copyright &y& Elsevier]

Abstract: Deposition of tantalum films for protective coatings on steel has been investigated. The desired tough and ductile bcc phase of tantalum, rather than the normally deposited hard and brittle tetragonal phase, has been grown by DC magnetron sputtering on unheated substrates first covered with thin layers of tantalum nitride. The nitride was formed by reactive sputtering with nitrogen gas, with the same DC magnetron source and target as used for deposition of tantalum. The crystal structure and composition of the nitride promoting the growth of bcc Ta, previously undefined, has been identified as the metastable fcc (NaCl like) TaN. Alignment of the (111) crystallographic planes of fcc TaN with (110) planes of bcc Ta is discussed as a possible mechanism for this effect. The minimum thickness of TaN underlayer on steel, required to promote the growth of bcc Ta, has been established and found to be dependent on the substrate surface preparation. Scratch tests with a diamond tip showed that the nitride underlayer does not compromise the film adhesion. Stable and well-adhering coatings of bcc Ta with thickness ranging from tens of nanometers to tens of micrometers on steel with a thin TaN underlayer were obtained. The process of deposition of bcc Ta films, including the formation of TaN underlayers is described in detail. [Copyright &y& Elsevier]

Abstract: TaN and Ta are used as diffusion-barriers for Cu interconnects in semiconductor microchips, and both these materials are patterned using the technique of chemical mechanical planarization (CMP). In the present work, we find satisfactory polish rates (∼120 nm/min) for both Ta and TaN by employing an alkaline slurry containing H2O2 and mixed abrasive particles. By combining potentiodynamic measurements with Fourier transform electrochemical impedance spectroscopy (FT-EIS), we show that the chemical mechanism for CMP of TaN is essentially identical to that we recently reported for Ta. This mechanism is governed by catalytic decomposition of H2O2 at the TaN–slurry interface, which leads to a local increase in the interfacial pH, and consequently, leads to conversion of Ta-oxide surface sites into soluble hexatantalate anions. [Copyright &y& Elsevier]

Abstract: Treatment of NbCl5 with excess HN(SiMe2Ph)2 in toluene resulted in the formation of crystalline [NbCl3(NSiMe2Ph)(NH2SiMe2Ph)]2. In the presence of excess 3,5-lutidine (3,5-Me2C5H3N), the reaction of TaCl5 with 2 equivalents of HN(SiMe3)2 resulted in the isolation of the monomeric complex [TaCl3(NSiMe3)(NC5H3Me2-3,5)2]. The X-ray crystal structure of [TaCl3(NSiMe3)(NC5H3Me2-3,5)2] has been determined. Low pressure chemical vapour deposition of [NbCl3(NSiMe2Ph)(NH2SiMe2Ph)]2 and [TaCl3(NSiMe3)(NC5H3Me2-3,5)2] forms thin films of niobium and tantalum nitride, respectively, at 600°C. [Copyright &y& Elsevier]

Abstract: This work investigates the thermal interactions of Cu/Ta–N/Ta/fluorinated silicate glass (FSG) structures after annealing up to 900 °C, where Ta–N layers are as-deposited amorphous TaNx (x∼0.5) or polycrystalline TaN films. It is found that both TaNx and TaN barriers possess excellent capability to prevent Cu from diffusing after annealing at 700 °C or lower. After annealing at 800 °C, however, inward diffusion of Cu occurred in Cu/Ta–N/FSG structures. The outward diffusion of fluorine was also observed. After annealing at 900 °C, reaction spots, which exposed the underlying FSG layer, were observed on the surface and formation of oxide phases was detected in the Cu/TaNx/FSG structure. However, exposure of FSG and oxidation were not found in the Cu/TaN/FSG structure. Nevertheless, in Cu/TaN/FSG structure, the sheet resistance was found to increase drastically after annealing at 900 °C. The significant increase in the sheet resistance could be attributed to the agglomeration of Cu. The influences of TaNx and TaN interlayers on the thermal stability of Cu/FSG system are discussed on the basis of chemical composition of these two Ta–N barriers. [Copyright &y& Elsevier]

Spectroscopic ellipsometry was successfully applied in the evaluation of the thermal stability of thin films in air by detecting the changes in film optical properties and thickness. Tantalum nitride (TaxNy) films with a nominal thickness of 30 nm were deposited on silicon wafer and annealed at different temperatures from 200°C to 700°C. Annealing-induced changes in thickness and optical properties of TaxNy were detected and determined by spectroscopic ellipsometry. Different approaches were adopted in the modeling and analysis of spectroscopic ellipsometric data. The results are consistent with the findings from Fourier Transform Infrared Spectroscopy (FTIR). [ABSTRACT FROM AUTHOR]

The main purpose of the present microstructural analysis by transmission electron microscopy (TEM) and X-ray diffraction was to investigate whether amorphous TaN films are a potential candidate as diffusion barrier for Cu wiring used in Si devices. The TaN thin films were prepared by a sputter-deposition technique using Ar and N2 mixed gas, and the film structure was found to be sensitive to the gas flow ratio of N2 vs. Ar during sputtering. Polycrystalline TaN films were obtained when the N2/(Ar+N2) ratio was smaller than 0.10 and amorphous TaN films were obtained when the ratio was larger than 0.15. Cross-sectional TEM observations revealed that the amorphous films had columnar structure with fine grains and that nano-scaled voids segregated at the boundaries. In addition, two-layered structures were observed in the amorphous TaN films and high density of the grain boundaries was formed close to the substrate. The present results suggested that the amorphous TaN films would not have high resistance against interdiffusion between two different materials because the density of grain boundaries with small voids was extremely high. [Copyright &y& Elsevier]

A 5 Å tantalum nitride (TaNx) thin film was deposited between the Hf- or Zr-doped TaOx high dielectric constant (high-k) film and silicon wafer to hinder the formation of the SiOx interface layer during the subsequent high-temperature annealing step. This interface contributes to the lower leakage current density, higher dielectric constant, and larger charge trapping. The improvement is attributed to the formation of the TaOxNy interfacial layer, which was confirmed by secondary ion mass spectroscopy and X-ray photoelectron spectroscopy. [Copyright &y& Elsevier]

Today it is possible to replace the costly Kjeldahl method by the commonly used Carrier Gas Hot Extraction (CGHE) method for the determination of nitrogen contents of up to 50 wt%, because the accuracy of this method was improved up to a 0.2% relative standard deviation. The remaining problem is the availability of defined and stable standards for N analyses by Carrier Gas Hot Extraction. In this study, we compared different certified standards with ℇ-TaN, which is a so-called “line compound” with a defined nitrogen content. A nitrogen content of almost theoretical composition was found for ℇ-TaN using compact samples analysed by CGHE and combustion-GC (Dumas-GC) analysis while the nitrogen content decreased in powdered samples. ℇ-TaN is a well-suited and stable potential reference material especially if the gas analyser is capable of analysing and decomposing compact pieces of this material. [ABSTRACT FROM AUTHOR]

As the fabrication dimension becomes smaller, it becomes increasingly difficult to ensure storage capacitance for DRAM. For this reason, a capacitor process using high-permittivity insulating films is strongly desired. In the research reported here, an MIM/tantalum pentoxide capacitor process is developed with ruthenium as an electrode material. The ruthenium CVD technique, the use of amorphous tantalum nitride as anti-oxide barrier metal, and a contamination elimination process using periodic acid have been developed. By packaging as 0.13-µm DRAM, capacitance performance equivalent to silica film is realized with a film thickness of 0.8 nm. The process is considered to be applicable to 0.10-µm DRAM. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 87(2): 26–36, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.10111 [ABSTRACT FROM AUTHOR]

The fluorine stability of two parylenes, aliphatic-fluorinated AF-4 (α, α, α′, α′ poly(p-tetrafluoroxylylene) and aromatic-fluorinated VT-4 (2, 3, 5, 6 poly(p-tetrafluoroxylylene), were investigated underneath Al, Al2O3, and TaNX overlayers with and without exposure to oxygen reactive-ion etching (RIE). No fluorine diffusion was observed for Al films deposited onto the as-received parylenes. However, after oxygen RIE, x-ray photoelectron spectroscopy (XPS) depth profiling detected fluorine diffusion throughout Al and to a lesser extent Al2O3 but in contrast to Ta2.67N. Metal-fluoride bonding was evident at the metal/parylene interface for all the overlayers after the parylene was exposed to oxygen RIE and annealed. [ABSTRACT FROM AUTHOR]

TaNx films sputtered from a TaN target were used as diffusion barriers between Cu thin films and Si substrates. Material characteristics of TaNx films and metallurgical reactions of Cu/TaNx/Si systems annealed in the temperature range 400–900 °C for 60 min were investigated by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, cross-sectional transmission electron microscopy, and sheet resistance measurements. We found that the deposition rate decreased with increasing bias. TaN, β-Ta, and Ta2N phases appeared and/or coexisted in the films at specific biases. A step change in N/Ta ratio was observed whenever a bias was applied to the substrate. After depositing a copper overlayer, we observed that the variation percentage of sheet resistance for Cu (70 nm)/TaNx (25 nm, x=0.37 and 0.81)/Si systems stayed at a constant value after annealing up to 700 °C for 60 min; however, the sheet resistance increased dramatically after annealing above 700 and 800 °C for Cu/TaN0.37/Si and Cu/TaN0.81/Si systems, respectively. At that point, the interface was seriously deteriorated and formation of Cu3Si was also observed. [Copyright &y& Elsevier]

TaN/C(carbon microcoils)/TaN composite microcoils/microtubes and pure TaN microcoils/microtubes were prepared by the vapor phase diffusion treatment (tentalizing and nitriding) of the carbon microcoils. The preparation conditions, morphologies and some properties of the microcoils/microtubes were examined. The carbon microcoils were completely modified to the TaN microcoils/microtubes by the treatment at 1200 °C for 20 h. The bulk electrical resistivity and specific surface area of the TaN microcoils/microtubes were 0.1–0.02 Ω cm and 5 m2 g−1, respectively. [Copyright &y& Elsevier]

Ta–N thin films were prepared by RF magnetron sputtering a Ta target in an Ar+N2 atmosphere, with the nitrogen gas flow ratio varying from 0 to 15%. The resistivity and deposition rate were measured and the microstructure of the films was characterized using glancing-angle X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Auger electron spectroscopy and X-ray photoelectron spectroscopy. The resistivity of the Ta–N films increases, while the deposition rate decreases, with increasing N2 flow. The N/Ta ratio of the Ta–N films sputtered with 1% of N2 is 1:2, while those of the films sputtered with 2.5–15% of N2 are all approximately 1. X-Ray diffraction reveals that the zero-N2 film shows a b.c.c. Ta structure, and the films with 1, 2.5–10 and 15% of N2 are amorphous, f.c.c. TaN and amorphous, respectively. However, electron diffraction shows that, in addition to the amorphous phase, the Ta–N film sputtered with 1% of N2 also contains nanocrystalline β-Ta and Ta2N phases. X-Ray photoelectron spectroscopy indicates that the 1% N2 Ta–N film shows an intermediate bonding state between metallic Ta and TaN, while the films with 2.5–15% N2 exhibit TaN bonding. Correlation between the film resistivity and the microstructral characteristics of sputtered Ta–N films is discussed. [Copyright &y& Elsevier]