Properties Of TiN Thin Films Research Articles

Kinetic properties of TiN thin films prepared by reactive magnetron sputtering

Results of investigations of kinetic properties of TiN thin films prepared by dc reactive magnetron sputtering are presented. It is established that the TiN thin films are polycrystalline and possess semiconductor n-type conduction. The carrier concentration is ∼1022 cm−3, while electron scattering occurs at ionized titanium atoms.

Influence of Annealing Temperature on Microstructural and Optical Properties of TiN Thin Films Deposited by DC Reactive Magnetron Sputtering

Polycrystalline TiN thin films were deposited on silicon and quartz substrates by DC reactive magnetron sputtering technique. The as-prepared thin films were annealed in air at various temperatures ranging between 400 °C to 700 °C. The effect of annealing temperatures on the microstructural and optical properties have been investigated by field emission scanning electron microscope, Raman scattering spectroscopy and UVVis spectrophotometer, respectively. The raman results indicated the presence of the rutile TiO2 phase for the samples annealed above 500°C. Many hollow-spherical structures appeared on the surface of films annealed at about 600 °C and the hollow-spherical structures occurred increasingly as a function of annealing temperatures. In addition, the optical properties of thin films depended strongly on annealing temperature.

The Effect of Film Thickness on Mechanical Properties of TiN Thin Films

The Effect of Film Thickness on Mechanical Properties of TiN Thin Films

Etch Properties of TiN Thin Film in Metal–Insulator–Metal Capacitor Using Inductively Coupled Plasma

Etch Properties of TiN Thin Film in Metal–Insulator–Metal Capacitor Using Inductively Coupled Plasma

Structural changes induced by argon ion irradiation in TiN thin films

In this work, the effects of 120 keV Ar+ ion implantation on the structural properties of TiN thin films were investigated. TiN layers were deposited by d.c. reactive sputtering on Si(100) wafers at room temperature or at 150?C. The thickness of TiN layers was ~240 nm. After deposition the samples were irradiated with 120 keV argon ions to the fluencies of 1?1015 and 1?1016 ions/cm2. Structural characterization was performed with Rutherford backscattering spectroscopy (RBS), cross-sectional transmission electron microscopy (XTEM), grazing angle X-ray diffraction (XRD) and atomic force microscopy (AFM). It was found that the argon ion irradiation induced the changes in the lattice constant, mean grain size, micro-strain and surface morphology of the TiN layers. The observed micro-structural changes are due to the formation of the high density damage region in the TiN thin film structure.

Preparation and Properties of TiN Thin Films by D.C. Reactive Magnetron Sputtering

TiN thin films were deposited by D.C reactive magnetron sputtering on glass and metal substrate. The relations between the technical conditions and the properties of the thin films are studied, According to control the intensity of gas pressure by changing the flux of Ar and N2, the structure of TiN films could be control. By changing the target power、N2 flux and substrate temperature, the relations between the technical conditions and the structure of TiN thin films were analyzed so as to produce the TiN thin films of excellent decorations, good corrosion resistance and high micro-hardness.

Ion beam modification of structural and electrical properties of TiN thin films

A study of ion beam modification of structural and electrical properties of TiN thin films is presented. The layers were deposited by reactive ion sputtering on (100) Si and glass slide substrates to a thickness of ∼240nm. After deposition the structures were implanted with argon ions at 120keV, to the fluences from 1×1015 to 1×1016ions/cm2. The ion energy was chosen to give the projected ion range within the deposited layers, to minimize the influence of the substrate on the induced structural changes. Structural analysis of the samples was performed by cross-sectional transmission electron microscopy, X-ray diffraction and Rutherford backscattering spectrometry. Electrical characterization included sheet resistivity measurements with a four point probe. It was found that the as-deposited layers have a columnar structure, individual columns stretching from the substrate to the surface and being a few tens of nanometers wide. Ion irradiation rearranges their crystalline structure, which remains polycrystalline, but the columns are broken, and nanocrystals of the same phase are formed. The structural changes can be nicely correlated to the measured electrical resistivity.

The properties of TiN thin films deposited by pulsed direct current magnetron sputtering

This work investigated the effect of sputtering pressure on the properties of titanium nitride films deposited by pulsed dc (direct current) magnetron sputtering. The pulse frequency was 60 kHz, and reverse time of pulse was 5 µs. The preferred-orientation of titanium nitride films transforms from (111) to (200) when the sputtering pressure decreases. At the same time, the deposition rate and hardness of films increase, while the resistivities of titanium nitride films decrease. Comparing with the continuous dc sputtering, the titanium nitride films prepared by pulsed dc process exhibit better properties. Although both pulsed and continuous dc sputtered films possess the same low resistivity 23 µΩ-cm under 0.75 Pa, the resistivities of pulsed dc films are relatively stable with respect to the variation of sputtering pressure. The pulsed dc films also exhibit higher hardness than continuous dc films.

Influence of deposition pressure on the structural mechanical and decorative properties of TiN thin films deposited by cathodic arc evaporation

TiN coatings can be obtained in a relatively wide range of compositions around stoichiometry. Changing the stoichiometry around the 1:1 composition broadens the spectrum of colors and can modify the mechanical properties as compared with those of stoichiometric TiN. In this work, we present the deposition of TiN coatings by using a metallic Ti cathode and varying the nitrogen partial pressure in a cathodic arc evaporation reactive process. The composition, crystalline structure, hardness and color of the different samples are characterized, and the effect of deposition pressure is discussed. The hardest coatings were deposited in the interval of deposition pressures between 5 and 20×10 −3 mbar. From the reflectance spectra in the visible range, a dominant wavelength of 581–582 nm is found for all the TiN samples, very close to that of the pure gold reference spectrum (579 nm) with purity colors that increase with the deposition pressure from 0.67 to 0.84 and approaches the color purity measured for the pure gold reference (0.91).

Effect of tantalum addition on microstructure and optical properties of TiN thin films

Titanium nitride thin films were deposited by direct current magnetron sputtering with various tantalum (Ta) concentrations (2, 4 and 8 at.%). The films were characterized using UV/VIS spectrophotometer. Atomic force microscopy (AFM), high resolution transmission electron microscope (HRTEM) were used to observe the microstructure and X-ray photoelectron spectroscopy was used to investigate the core level and the valence band of the films. It was found that the film with 2 at.% Ta is more reflective in the infrared range and more transparent in the visible region (selective behavior). The AFM showed smooth nanostructured surface for the film without Ta addition. It was found that the films with 2 at.% Ta presented relatively coarser grains with larger roughness and the reflectance are not controlled by the surface morphology. Also, this film presented higher electrical conductivity. HRTEM analysis showed that 2 at.% Ta addition gave rise to well crystallized films with elongated nanocrystallites in comparison with the films having 0, 4 and 8 at.% Ta contents.

Influence of Ge addition on the morphology and properties of TiN thin films deposited by magnetron sputtering

Thin films of TM–X–N (TM stands for early transition metal and X = Si, Al, etc.) are used as protective coatings. The most investigated among the ternary composite systems is Ti–Si–N. The system Ti–Ge–N has been chosen to extend the knowledge about the formation of nanocomposite films. Ti–Ge–N thin films were deposited by reactive magnetron sputtering on Si and WC–Co substrates at T s = 240 °C, from confocal Ti and Ge targets in mixed Ar/N 2 atmosphere. The nitrogen partial pressure and the power on the Ti target were kept constant, while the power on the Ge target was varied in order to obtain various Ge concentrations in the films. No presence of Ge–N bonds was detected, while X-ray photoelectron spectroscopy measurements revealed the presence of Ti–Ge bonds. Transmission Electron Microscopy investigations have shown important changes induced by Ge addition in the morphology and structure of Ti–Ge–N films. Electron Energy-Loss Spectrometry study revealed a significant increase of Ge content at the grain boundaries. The segregation of Ge atoms to the TiN crystallite surface appears to be responsible for limitation of crystal growth and formation of a TiGe y amorphous phase.

Effect of nitrogen flow rate on structure and properties of nanocrystalline TiN thin films produced by unbalanced magnetron sputtering

Nanocrystalline TiN thin films were deposited on (100) silicon wafers using an unbalanced magnetron (UBM) sputtering system. The structure and properties of the TiN thin films were studied under single-variable experimental condition by varying nitrogen flow rate ranging from 0.25 to 1.75 sccm. The grain size of the films was determined by X-ray diffraction (XRD), and the size was less than 7 nm. The images of transmission electron microscopy (TEM), scanning electron microscopy (SEM) and atomic force microscopy (AFM) also showed a nanometer-size grain structure of the TiN thin films. The N/Ti ratio increased (N/Ti=0.4–1.1) while the deposition rate decreased with increasing nitrogen flow rate. The preferred orientation changed from (111) to (200), then back to (111) as the nitrogen flow rate increased. There was no significant variation in the film hardness with nitrogen flow rate or preferred orientation. It is noted that the film hardness was high, ranging from 23.4 to 27.6 GPa, even for the film thickness down to 140 nm. The resistivity decreased with increasing packing factor. Ti/TiN nano-composite was found in the films with N/Ti ratio below 0.6.

Influence of nitrogen content on the structural, mechanical and electrical properties of TiN thin films

This paper reports on the preparation of TiN x thin films by d.c. reactive magnetron sputtering. The coating thickness ranged from 1.7 to 4.2 μm and the nitrogen content varied between 0 and 55 at.%. X-Ray diffraction showed the development of the hexagonal α-Ti phase, with strong [002] orientation for low nitrogen contents, where the N atoms fit into octahedral sites in the Ti lattice as the amount of nitrogen is increased. For nitrogen contents of 20 and 30 at.%, the ε-Ti 2N phase appears with [200] orientation. With further increasing the nitrogen content, the δ-TiN phase becomes dominant. The electrical resistivity of the different compositions reproduces this phase behavior. The hardness of the samples varied from approximately 8 GPa for pure titanium up to 27 GPa for a nitrogen content of 30 at.%, followed by a slight decrease at the highest contents. A similar increase of stresses with nitrogen is observed. Structure and composition with the consequent changes in crystalline phases and the lattice distortion were found to be crucial in the evolution of the mechanical properties.

Effects of Nitrogen Gas Flow and Film Thickness on Electric Properties of TiN Thin Film Deposited at Room Temperature

In this study, TiN thin film was deposited onto a glass substrate by the inclined opposite target type DC magnetron sputtering method with the good electric characteristics. The coating of TiN thin film was carried out onto substrate at the temperature of 303 K. The effects of nitrogen gas flow and film thickness on transparency, electric resistivity and electromagnetic wave shielding effectiveness of TiN thin films were discussed. The experimental results obtained were summarized as follows: (1) The TiN thin film deposited at the room temperature showed very low electric resistivity of 8.8×10-5Ω.cm. The TiN film showed the crystal structure when the depositing time was over 20 min. (2) When the film thickness of TiN was very thin, the TiN thin film was transparent for the visible light. The electric resistivity decreased with increasing the deposition time. (3) The electric resistivity and the transparency of TiN thin film depended greatly on the nitrogen gas flow.

OS04W0452 X-ray study of mechanical properties of TiN thin films with <001> fiber texture

OS04W0452 X-ray study of mechanical properties of TiN thin films with <001> fiber texture

Physical and morphological characterization of reactively magnetron sputtered TiN films

The present paper reports the influence of growth conditions on the properties of TiN thin films deposited by rf reactive magnetron sputtering in the low-pressure range. The effects of rf power at the Ti target and the negative bias voltage at the substrate in the morphology, structure, electrical resistivity and colour of the samples were studied in detail. X-Ray diffraction results showed that the δ-TiN phase ( a 0∼0.430 nm) is detected in all the samples. The sample prepared with grounded substrate revealed a lattice parameter close to the bulk value (0.424 nm), which is a consequence of a low stress state, due to the absence of ion bombardment. The sample deposited at 1000 W has a lattice parameter of 0.426 nm, close to that of the stress-free material ( a 0=0.424 nm), probably due to some stress relief. All films have a columnar-type structure, lying in the T and I zone of the Thornton Model. The resistivity of the TiN films is almost constant and close to 60 μΩ cm independently of the preparation conditions, except for the films deposited at 1000 W, ρ∼215 μΩ cm, and for the grounded sample, ρ∼153 μΩ cm. These values are probably due to cracks associated with stress relieves, in the first case, and the lack of ion bombardment that leads to films with lower density and higher number of defects in the second. No significant variations in colour were observed.

Correlation between microstructure and barrier properties of TiN thin films used Cu interconnects

In order to develop a fabrication process to prepare thermally stable TiN thin films, the TiN films were prepared by the sputter-deposition technique with various process parameters. The barrier property of the TiN films which prevented the Cu diffusion into Si or SiO 2 were found to be influenced by the radio-frequency power, Ar/N 2 gas ratio, and substrate temperature of the sputtering system. By adjusting these process parameters, the 25-nm-thick TiN films with excellent thermal stability that prevented the Cu diffusion at 850 °C for 30 min were successfully prepared. Microstructural analysis by X-ray diffraction and transmission electron microscopy indicated that the microstructure of the TiN films was sensitive to the thermal stability and that the TiN films with strong fiber structure and large grain size had higher resistance to the Cu diffusion into Si.

Optical characterization of TiN produced by metal-plasma immersion ion implantation

The dependence of the optical properties of TiN thin films prepared by metal-plasma immersion ion implantation (Me-PIII), using a cathodic arc as the source of Ti ions, on the pulse voltage and the gas composition was investigated. High voltage pulses up to −10 kV at a duty cycle of 9% were used while the gas flow was varied between 20 and 50 sccm. For all bias voltages TiN films oriented with the (100) axis normal to the surface was obtained. For the screened plasma energy ω ps a strong dependence on the gas mixture was found, increasing from 2.6 eV for high flow/current ( F N2/ I arc) ratios to more than 3.5 eV for low F N2/ I arc ratios. This is correlated with a reduction of the nitrogen content as the composition changes concurrently from TiN 0.95 to TiN 0.55.

Properties of Tin Thin Films Deposited by Alcvd as Barrier for Cu Metallization

AbstractIn advanced multi-level metallization schemes, the application of copper as interconnect metal requires the prevention of Cu diffusion into the active area and into interlevel dielectrics by total encapsulation of Cu with barrier films. Critical requirements for diffusion barriers are very small thicknesses, low resistivity, low deposition temperature and conformality on high aspect ratio trenches and vias. For this application, we have studied TiN films deposited by atomic layer chemical vapour deposition (ALCVD) at 400°C and 350°C. This paper discusses the ALCVD TiN films properties and compares them to the properties of TiN deposited by ionized physical vapour deposition (I-PVD).The ALCVD TiN deposited at 400°C exhibits a resistivity comparable to I-PVD TiN resistivity. However, the ALCVD films deposited at 350°C show higher resistivity. The Cl residue in ALCVD films is 1.5% at 400°C and 3% at 350°C. The microstructure is fine-grained. A very high level of conformality on trenches characterizes the ALCVD TiN films. We believe this property gives a clear advantage over the sputtered I-PVD TiN since its coverage in high aspect ratio trenches and vias is expected to be limited for the future devices interconnection scheme.

Electrical and colorimetric properties of TiN thin films prepared by DC reactive sputtering in a facing targets sputtering (FTS) system

The aims of the present work are twofold: first, to confirm the condition for obtaining gold–yellow TiN films without bias application; second, to examine the quantitative relationship between the colorimetric properties and electrical resistivity of these films. For the first aim, TiN films were prepared by DC reactive sputtering under a no-bias condition in the facing targets sputtering (FTS) apparatus, in which discharge is maintained even at a low gas pressure of less than 0.3 Pa. For the second aim, the color of the films was evaluated by means of the chromaticity coordinates, x and y, and the luminance factor Y, which is an index of the brightness based on a CIE standard colorimetric system. Gold–yellow TiN films having low resistivity were obtained, and a study of their electrical and colorimetric properties has provided the following conclusions. (i) The colorimetry of the films is affected by both the mixing ratio and total gas pressure. In particular, the brightness (the luminance factor) Y varied greatly with a change in total gas pressure. (ii) Even without bias application, a gold-colored TiN film with higher brightness Y has been obtained by deposition at an appropriate mixing ratio of N2/Ar and also under lower total gas pressure (ρ=0.31 μΩ m and Y=49 for the films deposited at 0.15 Pa). (iii) As the total gas pressure was increased, the column size, the surface roughness and oxygen content showed a clear increase. Thus, the films deposited under an atmosphere higher than 0.15 Pa had higher resistivity and lower brightness. (iv) Based on our results, the quantitative relationship between the resistivity and brightness of the TiN films is shown by the relation of ρ=775Y−2.