Titanium Nitride Deposition Research Articles

Remote plasma enhanced atomic layer deposition of titanium nitride film using metal organic precursor (C12H23N3Ti) and N2 plasma

Deposition of titanium nitride (TiN) thin films has been studied by remote plasma enhanced atomic layer deposition (PEALD) using MAP Ti (Mecaro Advanced Precursor-C12H23N3Ti) precursor and nitrogen plasma. Consequently, it was possible to use a temperature window of 275–325 °C, lower than the window required by other TiN films using TiCl4 precursor and NH3 gas. The auger electron spectroscopy (AES) analysis showed that as plasma power and plasma exposure times increase, impurity content decreases and TiN film deposited at plasma power of 400 W and exposure time of 35 s has lower impurity content than films deposited by other methods such as metal organic chemical vapor deposition (MOCVD). For TiN thin film deposited at 300 °C, plasma power of 400 W, and plasma exposure time of 35 s, the X-ray diffraction (XRD) analysis showed crystallinity and resistivity of approximately 320μΩcm. Atomic force microscopy (AFM) measurements determined a TiN film surface roughness of under 0.5 nm. TEM (transmission electron microscope) analysis showed 98% step coverage.

Thermal Atomic Layer Deposition of TiNx Using TiCl4 and N2H4

Atomic layer deposition (ALD) of titanium nitride (TiN) is carried out by the alternate surface reactions of titanium tetrachloride (TiCl4) and hydrazine (N2H4) at temperatures ranging from 150 to 350°C. The film deposition process is monitored in situ by quartz piezoelectric microweighing (QPM) and Fourier transform infrared spectroscopy (FTIRS). The QPM data detects the self-limiting character of the surface reactions between TiCl4 and N2H4, as well as the linearity of the film growth with the number of cycles at 200 and 225°C. The growth constant of the TiNx film is found to be 0.36 A/cycle at the optimum growth temperature of 275°C. The roughness and density of the 116.3-A-thick film deposited at this temperature are determined to be 7.2 A and 87.5% (of the TiN volume’s density), respectively. The X-ray photoelectron spectroscopy (XPS) analysis of these films shows the content of chlorine impurities to be below the instrument’s sensitivity limit (<0.2 аt %) and the oxygen content to be near 14 at %. The X-ray diffraction measurements indicate the cubic polycrystalline structure of these films. The FTIRS method is used for surface deposition chemistry at 200 and 275°C. The possibility of depositing titanium-aluminum nitride (TiAlxNy) films by ALD with trimethylaluminum (TMA) as a precursor is also shown. Films deposited at 275°С are found to contain oxygen and chlorine impurities near 3 and 4 at %, respectively.

Mechanism of titanium–nitride chemical mechanical polishing* *Project supported by the National Natural Science Foundation of China (Grant Nos. 61874178 and 61874129) and the National Key Research and Development Program of China (Grant Nos. 2018YFB0407500 and 2017YFA0206101).

During the preparation of the phase change memory, the deposition and chemical mechanical polishing (CMP) of titanium nitride (TiN) are indispensable. A new acidic slurry added with sodium hypochlorite (NaClO) as an oxidizer is developed for the CMP of TiN film. It has achieved a material removal rate of 76 nm/min, a high selectivity between TiN film and silica (SiO2) films of 128:1, a selectivity between TiN film and tungsten film of 84:1 and a high surface quality. To understand the mechanism of TiN CMP process, x-ray photoelectron (XPS) spectroscope and potentiodynamic polarization measurement are performed. It is found that the mechanism of TiN CMP process is cyclic reaction polishing mechanism. In addition, both static corrosion rate and the inductively coupled plasma results indicate TiN would not be dissolved, which means that the mechanical removal process of oxide layer plays a decisive role in the material removal rate. Finally, the mechanism of TiN polishing process is given based on the analysis of surface potential and the description of blocking function.

Corrosion resistance of functionally graded TiN/Ti coatings for proton exchange membrane fuel cells

Bipolar Plates (BPP) are important components of proton exchange membrane fuel cell (PEMFC) stacks. In the development of innovative fuel cell designs, it is advantageous to use aluminum for these applications, however, this material lacks the necessary corrosion resistance. Since the performance of PEMFC stacks depends on BPP properties, in particular, corrosion resistance, depositing titanium nitride (TiN) thin films onto aluminum substrates may improve their efficiency and durability. The present work focuses on improving corrosion resistance and hydrophobicity of TiN/Ti by using N graded films deposited onto aluminum substrates (AA-1100) by grid-assisted magnetron sputtering (GAMS). Electrochemical impedance spectroscopy (EIS) and potentiodynamic and potentiostatic polarization are used to investigate the performance of the substrate/film system at room temperature and 70 °C, thus simulating a prototypic PEMFC electrolyte environment. Electrochemical test results showed that graded TiN films improved corrosion resistance when compared with both the homogeneous films and the AA1100 uncoated substrate. Furthermore, contact angle results reveal improved hydrophobicity for both homogeneous and graded TiN coatings when compared with the AA1100 substrate.

Multi-objective optimization of Pulsed direct current magnetron sputtered titanium nitride thin film using Grey relational analysis

Titanium nitride coatings are extensively adopted as an intermediate adhesion layer in the cutting tools because of its superior mechanical properties. The interdependence of each process parameter during the deposition of such a coating process is nonlinear, and hence, it becomes a challenge to determine the output responses without carrying out a wide range of experiments. So to minimize the experiments, Taguchi-based L9 design of experiments were employed in this study with three factors and three levels such as Argon (Ar): Nitrogen (N2) gas mixture, Pulsed direct current power, and deposition time for depositing titanium nitride thin films on silicon (100) and tungsten carbide substrates using Pulsed direct current magnetron sputtering technique, where conventional direct current magnetron sputtering cannot be deployed using titanium nitride target. Multiple output responses such as average thickness, surface roughness, nano-hardness, Young’s modulus, wear track deformation, and coefficient of friction were measured by carrying out the systematic investigations, and a single optimum solution was obtained using Grey relational analysis. From the Grey relational analysis, the optimum Ar:N2 gas flow mixture, Pulsed direct current power, and deposition time for improved titanium nitride adhesion layer are 300 W, 10:5 sccm, and 5 min, respectively. Further, grazing incidence x-ray diffractometer profiles of deposited films exhibits (111) and (200) reflections corresponding to the titanium nitride phase, and the morphological analysis also revealed the existence of strongly faceted nano-grains with a triangular-shaped morphology.

Synthesis of TiN and TiO2 thin films by cathodic cage plasma deposition: a brief review

The cathodic cage plasma deposition (CCPD) is an advanced technique recently developed from an active screen plasma nitriding system, which has been used for thin film deposition such as titanium nitride and titanium dioxide (TiO2). These coatings can improve the physical, mechanical, and optical properties of numerous materials, and such coatings can be developed by several techniques. Unfortunately, the conventional deposition techniques exhibit certain drawbacks, including high cost, the complexity of the operation, very low pressure, and high processing temperature; as a result, CCPD is an advantageous technique. In this review, brief information on the deposition of titanium nitride and oxide coatings on steel alloys, titanium, glass, and silicon substrates, and the effect of control parameters on deposition efficiency is provided. The effectiveness of this system for the synthesis of thin films on various substrates, including insulators and conductors, is also summarized. The recent developments and applications of CCPD for titanium-based coatings are described in detail.

Correlation between ferroelectricity and nitrogen incorporation of undoped hafnium dioxide thin films

The ferroelectric characteristics of undoped hafnium oxide (HfO2) in titanium nitride (TiN)/HfO2/TiN stacks exhibited improved remanent polarization by controlling the nitrogen gas flow during TiN deposition in this work. Electrical measurements revealed that samples with a higher N2/(Ar + N2) ratio obtained a higher remanent polarization of approximately 10 μC/cm2 at 2.5 V but exhibited a larger leakage current and less reliability. Among all the samples, the sample with a N2/(Ar + N2) ratio of 33% exhibited a relatively high remanent polarization of 12 μC/cm2 and excellent endurance over 108 cycles. Through X-ray photoelectron spectroscopy (XPS) analysis, it was observed that increasing the N2 gas flow during TiN electrode deposition contributed to excessive N-diffusion, leading to the creation of more oxygen vacancies and subsequently to device failure. Therefore, controlling the appropriate N2 gas flow during TiN deposition is crucial to enhance the ferroelectric characteristics of undoped HfO2. The results of this study may be applicable to future work on nonvolatile memory applications.

Application of a Novel CVD TiN Coating on a Biomedical Co-Cr Alloy: An Evaluation of Coating Layer and Substrate Characteristics.

Titanium nitride (TiN) was deposited on the surface of a cobalt–chromium (Co–Cr) alloy by a hot-wall type chemical vapor deposition (CVD) reactor at 850 °C, and the coating characteristics were compared with those of a physical vapor deposition (PVD) TiN coating deposited on the same alloy at 450 °C. Neither coating showed any reactions at the interface. The face-centered cubic (fcc) structure of the alloy was changed into a hexagonal close-packed (hcp) phase, and recrystallization occurred over at 10 μm of depth from the surface after CVD coating. Characteristic precipitates were also generated incrementally depending on the depth, unlike the precipitates in the matrix of the as-cast alloy. On the other hand, the microstructure and phase of the PVD-coated alloy did not change. Depth-dependent nano-hardness measurements showed a greater increase in hardness in the recrystallization zone of the CVD-coated alloy than in the bulk center of the alloy. The CVD coating showed superior adhesion to the PVD coating in the progressive scratch test. The as-cast, PVD-coated, and CVD-coated alloys all showed negative cytotoxicity. Within the limitations of this study, CVD TiN coating to biomedical Co–Cr alloy may be considered a promising alternative to PVD technique.

Effect of Contact Plug Deposition Conditions on Junction Leakage and Contact Resistance in Multilevel CMOS Logic Interconnection Device.

Here, we developed the optimal conditions in terms of physical and electrical characteristics of the barrier and tungsten (W) deposition process of a contact module, which is the segment connecting the device and the multi-layer metallization (MLM) metal line in the development of 100 nm-class logic devices. To confirm its applicability to the logic contact of barrier and W films, a contact hole was formed, first to check the bottom coverage and the filling status of each film, then to check the electrical resistance and leakage characteristics to analyze the optimal conditions. At an aspect ratio of 3.89:1, ionized metal plasma (IMP) Ti had a bottom coverage of 40.9% and chemical vapor deposition (CVD) titanium nitride (TiN) of 76.2%, confirming that it was possible to apply the process to 100 nm logic contacts. W filling was confirmed, and a salicide etching rate (using Radio Frequency (RF) etch) of 13–18 Å/s at a 3.53:1 aspect ratio was applied. The etching rate on the thermal oxide plate was 9 Å/s. As the RF etch amount increased from 50–100 Å, the P active resistance increased by 0.5–1 Ω. The resistance also increased as the amount of IMP Ti deposition increased to 300 Å. A measurement of the borderless contact junction leakage current indicated that the current in the P + N well increased by more than an order of magnitude when IMP Ti 250 Å or more was deposited. The contact resistance value was 0.5 Ω. An AC bias improved the IMP Ti deposition rate by 10% in bottom coverage, but there was no significant difference in contact resistance. In the case of applying IMP TiN, the overall contact resistance decreased to 2 Ω compared to CVD TiN, but the distribution characteristics were poor. The best results were obtained under the conditions of RF etch 50 Å, IMP Ti 200 Å, and CVD TiN 2 × 50 Å.

Obliquely Deposited Titanium Nitride Nanorod Arrays as Surface-Enhanced Raman Scattering Substrates.

In this work, titanium nitride (TiN) nanorod arrays were prepared as surface-enhanced Raman scattering (SERS) substrates using glancing angle deposition (GLAD) in a magnetron sputtering system. The nitrogen flow rate was varied from RN2 = 1 to 3 sccm, yielding five TiN uniform thin films and five TiN nanorod arrays. The figure of merit (FOM) of each TiN uniform film was measured and compared with the SERS signal of each TiN nanorod array. Rhodamine 6G (R6G) was used as the analyte in SERS measurement. For an R6G concentration of 10−6 M, the analytical enhancement factor (AEF) of the TiN nanorod array that was prepared at RN2 = 1.5 sccm was 104. The time-durable SERS performance of TiN nanorod arrays was also investigated.

Study of TiN and TaN Underlayer Properties and Their Influence on W Growth

The changes in tungsten (W) film growth and resistance are studied using different titanium nitride (TiN) and tantalum nitride (TaN) underlayer films. The underlayers are analyzed by surface characterization techniques to obtain the differences in surface morphology and grain sizes that influence the growth of W on these films. Different precursors and processes used for TiN deposition affect the W growth and film properties. It is important to monitor the changes in incoming TiN resistance as a part of the W process qualification. This enables maintaining W process stability and reducing fab downtime due to false fails.

Highly Plasmonic Titanium Nitride by Room-Temperature Sputtering

Titanium nitride (TiN) has recently emerged as an attractive alternative material for plasmonics. However, the typical high-temperature deposition of plasmonic TiN using either sputtering or atomic layer deposition has greatly limited its potential applications and prevented its integration into existing CMOS device architectures. Here, we demonstrate highly plasmonic TiN thin films and nanostructures by a room-temperature, low-power, and bias-free reactive sputtering process. We investigate the optical properties of the TiN films and their dependence on the sputtering conditions and substrate materials. We find that our TiN possesses one of the largest negative values of the real part of the dielectric function as compared to all other plasmonic TiN films reported to date. Two-dimensional periodic arrays of TiN nanodisks are then fabricated, from which we validate that strong plasmonic resonances are supported. Our room-temperature deposition process can allow for fabricating complex plasmonic TiN nanostructures and be integrated into the fabrication of existing CMOS-based photonic devices to enhance their performance and functionalities.

Proton exchange membrane (PEM) fuel cell bipolar plates prepared from a physical vapor deposition (PVD) titanium nitride (TiN) coated AISI416 stainless-steel

Metal nitrides (and particularly TiN) are among the most extensively investigated proton exchange membrane fuel cell bipolar plates (BP) coatings. The most employed methods of nitrides coating deposition are various modifications of physical vapor deposition (PVD), while different types of stainless steels are the most common BP materials coated with TiN PVD films. In the current work, we report on the integrity maintenance of TiN PVD coating of AISI416, considering this as a clue to the sustainability of such a film. The advantage of this combination lies in the fact that the coefficients of thermal expansion (CTE) of this alloy is close to the CTE of the TiN film. Thus, the thermal stresses of such coating are expected to be minimal, as well as related coating cracks. We conducted a thorough surface analysis of roughness evolution in the course of BP corrosion process, investigating different initial surface pretreatments. Finally, we found that fine mirror-like polished BP substrate prior to deposition is essential for TiN film’s integrity during corrosion analysis time.

Surface Characteristics of Plasma Treated and Titanium Nitride (TiN) Deposited Aluminum Alloy

Abstract This investigation highlights the rationale of the magnetron sputtering technique to deposit titanium nitride (TiN) coatings on aluminum alloy 2024 (AA 2024). TiN deposition on aluminum was systematically optimized, with nitrogen flow rate (mL/min) as the varying parameter. The developed TiN coatings were compared with the atmospheric pressure plasma treated and raw (uncoated) AA 2024 aluminum substrate surface. The crystalline phase formations of TiN on the alloy surface were studied using X-ray diffractometer technique. The scanning electron microscopy imaging technique was used to study the morphology of the formed ceramic layer. Fine and pore-free grains of TiN on the alloy surface were obtained at 1.5 mL/min nitrogen flow rate (TiN layer thickness ∼ 630 nm). X-ray photoelectron spectroscopy analysis was conducted on the surface in order to characterize elemental composition of the surface. Surface characteristic and wettability studies on the developed coatings were conducted using atomic force microscopy (AFM) and by measurement of contact angle, respectively. The roughness parameter (Ra) (obtained from AFM) increased by ∼72 % with TiN deposition on the AA 2024, while the contact angle value decreased by ∼18 %. The adhesion of the coating to the metal substrate (using scratch test) and the Vickers hardness measurements were also performed. Corrosion resistance imparted by the coatings was also confirmed from the electrochemical measurements. A significant positive shift in the corrosion potential (Ecorr) value from −0.96 V to −0.75 V was observed from the analysis.

Effect of the substrate on structure and properties of titanium nitride films grown by plasma enhanced atomic layer deposition

The authors deposited titanium nitride (TiN) films by plasma-enhanced atomic layer deposition on various types of amorphous, polycrystalline, and single crystalline substrates and found that the crystallinity of the substrate strongly affects the morphology, orientation, and resistivity of the films. An appropriate substrate choice yields TiN films with bulk resistivity values of about ∼20 μΩ cm. The preferred crystallographic orientation of the films, either (111) or (001), does not affect film resistivity.

Durability of nano-reinforced polyimide adhesive bonding of titanium nitride deposited aluminium for aerospace applications

This investigation highlights novel surface modification techniques of aluminium by titanium nitride deposition to increase adhesion characteristics of aluminium, when fabricated by polyimide adhesive (PI) and its durability under aerospace environments. The aluminium substrate surface when modified by titanium nitride deposition under physical vapour deposition (PVD), its adhesion strength increases considerably. Incorporation of nano particles in to the polyimide adhesive increases cohesive properties of the adhesive up to a great extent. It is observed that surface modified aluminium shows better adhesion properties in comparison to unmodified aluminium surface because surface modified aluminium results strong interfacial force of attraction with the polyimide adhesive. Addition of silica nano powder increases the adhesive bond strength considerably. However, it is observed that adhesive bond strength increases up to an optimum dispersion of silica nano powder and thereafter it decreases. Thermogravimetric Analysis (TGA) reveals that there is an improvement of thermal stability of the adhesive due to dispersion of silica nano powder. Effects of surface modification of aluminium and reinforced nanoparticles on durability were analysed. It is observed that due to titanium nitride deposition on aluminium and dispersion of silica nano powder in to the polyimide adhesive increases the durability of the adhesive joint up to certain extent. Failure analysis under Scanning Electron Microscopy (SEM) reveals that there is interfacial failure of adhesive bonded joints of unmodified aluminium and in the case of titanium nitride deposited aluminium, the adhesive joint fails cohesively resulting in significant increase in adhesive bond strength.

Study on Interface Engineering of TiN/SiO2 Layers to Reduce the Parasitic Capacitance in CMOS Circuits

Recent developments in CMOS (Complementary Metal-Oxide-Semiconductor) technology have heightened the need for high-quality interface between mold and metal line, in order to decrease the RC delay in CMOS circuit. This technical trend indicates that the understanding of the interface reaction between the silicon dioxide (SiO2) and the titanium nitride (TiN) is emerging as an important issue in the thin film deposition process. However, only few researchers have focused on the interface researches to investigate the formation of parasitic capacitance and its material properties of TiN/SiO2 layer. In this work, we report the formation mechanism of Titanium dioxide (TiO2) on SiO2 surface during the TiN deposition process based on a Plasma Enhanced Chemical Vapor Deposition (PECVD) and Titanium tetrachloride (TiCl4) gas reactions. This research has explored the effects of the partial pressure of TiCl4 gas in the initial step of TiN deposition on the formation of the intermetallic compound of TiN/SiO2 interface layer. The results of atomic composition and the position of valance band of the composite material analyzed by X-ray photoelectron spectroscopy (XPS) reveals that the parasitic capacitance material is the TiO2. The high partial pressure of TiCl4 leads to an increased oxygen-titanium ratio (O/Ti ratio) and a decreased maximum position of valance band at the interface between TiN and SiO2, which is attributed to TiO2 formation. Furthermore, we investigated the effect of the thickness of TiO2 and its Oxygen intensity induced by TiCl4 gas treatment on the change of the parasitic capacitance using X-ray fluorescence (XRF) analysis and Secondary Ion mass spectrometry (SIMS).

Substrate slip steps promote cracking and buckling of thin brittle film

Cracking and buckling are the two major failure phenomena of brittle film/metal substrate structures. Herein, by depositing titanium nitride brittle films with strong and poor adhesion on stainless steel substrates, we report that the substrate slip steps promote the cracking and the ensuing buckling process of them. The large stress concentration at the interface due to film the inhibitory effect on dislocations in the substrate, contributes to the film breakage and the interface delamination. The small separation of interface allows the easier formation of slip steps, thus accelerating the buckling process under compressive stress due to Poisson's contraction.

Synthesis and Characterization of Titanium and Titanium Nitride Deposition on High Speed Steel Substrate

Abstract In the present study, titanium and titanium nitride are deposited on the high speed steel at ambient temperature and the tribological behavior is investigated. The deposited high speed steels are characterized by different experimental techniques. scanning-electron microscopy (SEM) is used for film morphology and fractured cross-section examination. However, Profilometer is used for measuring the film thickness and roughness. Nano-indentation is used to extract the intrinsic hardness and youngs modulus evaluation. Ball on-disc sliding test under dry condition at ambient temperature is employed for tribological properties of deposited high speed steels. The test results indicate the improvement in the hardness of titanium nitride deposited high speed steel as compared to other deposition leads to improvement in the tribological properties. The tribological properties have been correlated with the hardness and the morphology of the worn surfaces.

The effect of the surface structure of titanium alloy medical screws on their wear resistance

In this work, the effect of vacuum ion-plasma treatment on the wear resistance of the medical screws surface made of VT6 titanium alloy is studied as well as on the mechanical characteristics of the screws in contact with the plate for osteosynthesis. It is shown that the TiN titanium nitride deposition on the screw head increases the surface microhardness by 3 times and also provides lowering the torque during removal of the screw out of the plate.