Chemical Vapor Deposition TiN Research Articles

Growth and Properties of TiN/Al2O3/Ti(C, N)/TiN Multilayer CVD Coatings on Ti (C, N)-Based Cermet Substrates with Ni, Co and Fe Binders

In this article, Ti (C, N)-based cermets with Ni, Co and Fe binder phase were manufactured by traditional powder metallurgical techniques. The multilayer TiN/Al2O3/Ti (C, N)/TiN CVD (chemical vapor deposition) coatings were deposited on the three kind of cermets, and the growth and properties of the coatings were studied. The results show that massive cores-incomplete rims are found in the cermet-Ni (cermets with Ni binder) and cermet-Fe (cermets with Fe binder), while in the cermet-Co (cermets with Co binder), the small black cores are surrounded by a complete and well-developed rim phase. When the TiN coating is deposited on the cermets with cores-incomplete rims, the Ti and N atoms stack on the face-centered cubic structure of Ti (C, N) first, and epitaxial growth of the TiN crystals takes place. The epitaxial growth is attributed to the same preferred orientation (2 0 0) of the TiN layers to the Ti (C, N) of the substrate. While on the cermets with cores-complete rims, (Mo, Ti) (C, N) solid solution and binder phase (Ni/Co/Fe), which has a distinct crystal structure or lattice parameters, TiN grains nucleate first and then grow. In this case, the TiN coatings show a (1 1 1)-oriented structure. Dense and thin coatings grow on the cermets-Co. The adhesion of the multilayer coatings to the substrate increases in the order cermets-Fe, cermets-Ni and cermets-Co. In addition, the coating on the cermets-Co has the lowest COF (coefficient of friction) as the thin TiN layer (0.7 μm) is propitious to diffusion of Al and O, and a protective transfer layer is formed by AlOx.

Comparison of Growth Characteristics and Properties of CVD TiN and TiO2 Anti-Coking Coatings

Coating metals with anti-coking materials inhibit their catalytic coking and are especially beneficial in the pyrolysis of hydrocarbon fuels. It is believed that growth characteristics and properties may play a pivotal role in the anti-coking performance of chemical vapor deposition (CVD) coatings. In this study, TiN and TiO2 coatings were obtained by CVD using TiCl4–N2–H2 and TiCl4–H2–CO2 systems, respectively. The effects of deposition time, residence time, and partial pressure were examined, and the coating microstructure was characterized by scanning electron microscopy (SEM). The results reveal that the effect of deposition parameters on the growth characteristics of TiN and TiO2 coatings is very different. The growth of the TiN coating shows characteristics of the island growth model, while the TiO2 coating follows the layer model. In general, the growth rate of the star-shaped TiN crystals is higher than that of crystals of other shapes. For the TiO2 coating, the layer mode growth characteristics indicate that the morphology of the TiO2 coating does not change significantly with the experimental conditions. Coking tests showed that the morphology of non-catalytic cokes is not only affected by the temperature, pressure, and coking precursor, but is also closely related to the surface state of the coatings. Both TiN and TiO2 coatings can effectively prevent catalytic coking and eliminate filamentous cokes. In some cases, however, the N or O atoms in the TiN and TiO2 coatings may affect common carbon deposits formed by non-catalytic coking, such as formation of needle-like and flaky carbon deposits.

Impact of TiN Barrier Layer on Contact Resistance of Tungsten Filled Vias

In this paper, we directly compare the influence of sputtered and chemical vapor deposited TiN liners on the contact resistance of large tungsten filled vias with an aspect ratio of 3:1. Scanning transmission electron microscopy, energy-dispersive X-ray spectroscopy, and time-of-flight secondary ion mass spectrometry studies revealed that during WF6-based tungsten chemical vapor deposition (CVD), fluorine diffuses through a poor physical vapor deposited (PVD) TiN barrier layer and reacts with the underlying titanium and aluminum to form high resistive compounds. Aside from depositing a thicker TiN PVD barrier, the replacement of the 40 nm PVD layer with a thinner TiN CVD liner has led to significantly reduced via resistances with very small deviations across the wafer and lot. We show that the CVD layer has a superior barrier performance against fluorine penetration, provides a conformal coverage and can be used at a reduced thickness compared to the PVD process.

Control of the electrical resistivity of Ni-Cr wires using low pressure chemical vapor deposition of tin

Control of the electrical resistivity of Ni-Cr wires is demonstrated using low pressure chemical vapor deposition (LPCVD) of tin on the surface of the wire, after which the effects of the deposition temperature on the structural, morphological, and compositional characteristics of the tin-deposited Ni-Cr wires are investigated. As the deposition temperature is increased, the resistivity of the Ni-Cr wires increases in the temperature range 300–400°C; then remains nearly constant as the temperature increased to 700°C. The increase in the resistivity of the Ni-Cr wires is attributed to formation of Ni3Sn2 particulates on the surface of the wire. Compositional analysis shows that the pattern of change in the tin content with the deposition temperature is similar to that of resistivity with temperature, implying that the atomic content of tin on Ni-Cr directly affects the electrical resistivity.

Study on the Effect of Plasma Treatment on Flat-band-voltage and Equivalent Oxide Thickness using Metal-organic Chemical Vapor Deposition TiN Film as p-MOSFETS Metal Gate Electrode

This work aimed to study on the effects of plasma treatment on flat band voltage (Vfb) and equivalent oxide thickness (EOT) using Metal-organic Chemical Vapor Deposition (MOCVD) TiN film as p-MOSFETs metal gate electrode. Theplasma treatment conditions effect on the resistance and composition properties of MOCVD TiN, consequently, they can modulate work function and control threshold voltage. The effects of “plasma treatment” were imposed to favor the formation of Ti-N bonds, thus decreasing the rate Ti-C bond and favoring a crystallized stoichiometric TiN phase to increase PMOS Vfb shift. Meanwhile, plasma treatments accelerate interfacial oxide formation and increase EOT. On the other hand, EOT increases with the increase of plasma treatment time and power in this work, but Vfb does not always increase and reach a max value.

Numerical Simulation of Heat and Mass Transfer during Nanosecond Laser Chemical Vapor Deposition on a Particle Surface

Chemical vapor deposition of TiN on a spherical particle surface subjected to nanosecond laser heating is simulated numerically here. A thermal model is developed to describe the heat transfer within the particle, chemical reaction on the particle surface, and mass transfer in the gases. The heat conduction and mass diffusion equations are discretized using the finite volume method with fully implicit schemes, and solved with tridiagonal matrix method. Temporal distributions of particle surface temperature and deposited film thickness resulting from multiple-pulse irradiation are analyzed for a wide range of parameters including laser fluence, pulse repetition frequency, pulse width, initial particle temperature, particle radius, and total pressure in the reaction chamber.

Influence of Precursor Chemistry on Morphology and Composition of CVD-Grown SnO2 Nanowires

Tin oxide (SnO2) nanowires (NWs) were synthesized via the gold-catalyzed chemical vapor deposition of tin(IV) and tin(II) precursors, namely, [Sn(OtBu)4] (1) and [Sn(OtBu)2]2 (2). Nanowires were de...

Effects of Post-SiH4 and Plasma Treatments on Chemical Vapor Deposited Cu Seeds with Chemical Vapor Deposited TiN Barrier in Porous Low Dielectric Constant and Cu Integration

A Cu seed deposited by chemical vapor deposition (CVD) was integrated with a CVD TiN barrier and electroplated Cu in a double level metal interconnect scheme using a dual damascene process. The post-SiH4 treatment of CVD TiN inhibits agglomeration of thin Cu by improving the wettability of Cu seeds as well as reducing the TiN sheet resistance. Post-plasma treatment on CVD Cu seeds decreases impurities in CVD Cu and eliminates interface voids between the CVD Cu seed and electroplated Cu, improving the gap filling properties of electroplated Cu layers. Inherently poor adhesion of the CVD Cu layers between the Cu barrier metal and the electroplated Cu is overcome by CVD TiN post treatments and CVD Cu post-plasma treatment. Bias-thermal-stress (BTS) tests were performed to verify the effect of post-SiH4 treatment. The SiH4 treated CVD TiN barrier and CVD Cu seed show feasibility for 65-nm technology in terms of low via resistance and chain yields.

Effects of Post-SiH4and Plasma Treatments on Chemical Vapor Deposited Cu Seeds with Chemical Vapor Deposited TiN Barrier in Porous Low Dielectric Constant and Cu Integration

A Cu seed deposited by chemical vapor deposition (CVD) was integrated with a CVD TiN barrier and electroplated Cu in a double level metal interconnect scheme using a dual damascene process. The post-SiH4 treatment of CVD TiN inhibits agglomeration of thin Cu by improving the wettability of Cu seeds as well as reducing the TiN sheet resistance. Post-plasma treatment on CVD Cu seeds decreases impurities in CVD Cu and eliminates interface voids between the CVD Cu seed and electroplated Cu, improving the gap filling properties of electroplated Cu layers. Inherently poor adhesion of the CVD Cu layers between the Cu barrier metal and the electroplated Cu is overcome by CVD TiN post treatments and CVD Cu post-plasma treatment. Bias-thermal-stress (BTS) tests were performed to verify the effect of post-SiH4 treatment. The SiH4 treated CVD TiN barrier and CVD Cu seed show feasibility for 65-nm technology in terms of low via resistance and chain yields.

Selected Thermochemical Parameters for Tin(II) Halides, SnXX′ (X, X′ = Cl, Br, I)

The tin(II) halides are important in a number of industrial processes and technological devices, for example, in the chemical vapor deposition of tin(IV) oxide films for the semiconductor industry, in the production of catalysts, and as a method of refining the spectral output of high intensity discharge lamps. Modeling of such processes requires databases of reliable, self-consistent thermochemical parameters. A survey of the physicochemical properties and appropriate standard thermochemical data has been made for the tin(II) halides, SnXX' (X, X' = Cl, Br, I), and a self-consistent set of thermochemical parameters are selected for the solid, liquid, and gas phases of these materials. In a few cases where data are simply unavailable, data are derived using a variety of estimation techniques. The benchmark employed to select the parameters in this work is that they accurately predict experimental vapor pressures where these are available. Finally, estimation techniques (Supporting Information) are used to provide supporting evidence as to the correctness of the magnitudes of data selected using the benchmark.

Characteristics of ALD Tungsten Nitride Using B2H6, WF6, and NH3 and Application to Contact Barrier Layer for DRAM

Tungsten nitride thin films were grown by atomic layer deposition (ALD) within the temperature range of from diborane , tungsten hexafluoride , and ammonia for application to a contact barrier layer in dynamic random access memory (DRAM). Herein, was used as an additional reducing agent to produce a low-resistivity film, and its resistivity was in the range of , depending on the deposition conditions for the thick film. An increase in the growth rate was observed with increasing deposition temperature, but an almost constant growth rate of was obtained in the temperature range from . The properties of the as-deposited film, including the resistivity, ratio, density, B and F impurity content, and phase, were affected by the deposition temperature and flow rate during the process. As the deposition temperature and flow rate increased, the ratio and film density increased and the impurity content decreased, leading to a reduction in the resistivity of the film. An increased ratio was found to be favorable to the formation of a face-centered-cubic phase. Excellent step coverage was obtained even on a diameter contact hole with an aspect ratio of 16:1. The film in this study was thermally stable to annealing at for , but after annealing at , it converted to body-centered-cubic with the accompanying release of N. The film was evaluated as a barrier layer for W-plug deposition for design-rule DRAM. The results showed that the integration scheme with showed lower contact resistance than metallorganic chemical vapor deposition TiN or -based chemical vapor deposited TiN.

Bio-mimetic surface structuring of coating for tribological applications

A novel multilayered coating was developed for applications associated with friction reduction and wear resistance improvement. The nano-engineered coating integrates a soft lubricating layer, consisting of MoS 2–PTFE, onto hard load-supporting layers, with controlled surface morphology (roughness and patterning) of cBN–TiN. The coating was synthesized by sequential procedures including electrostatic spray deposition of cBN particles with different average particle sizes, chemical vapor deposition of TiN, deposition of nano- and micro-sized MoS 2 dispersed in PTFE, and curing. The effect of cBN particle size (with different combinations of particle size) and deposition parameters (specifically electrical voltage) on the cBN–TiN surface morphology were studied experimentally and optimized. SEM characterization of the as-synthesized cBN–TiN coating shows surface features similar to that of colocasia esculenta, with alternating nano- and micro-sized domes and “pockets”; the MoS 2–PTFE top layer has MoS 2 particles retained in the pockets by a basket structure formed during PTFE curing. Tribological and scratch tests were carried out for the as-prepared cBN–TiN and cBN–TiN/MoS 2–PTFE multilayered coatings. Sliding test results demonstrate significantly lower friction coefficient for the multilayered coating, showing that the unique integration of soft lubricating layer and biomimetically structured hard layer can effectively improve tribological performance. It is suggested that lubrication at the frictional contacts was realized by continuous release of the lubricants, MoS 2 and PTFE, from the pockets.

Impact of TiN post-treatment on metal insulator metal capacitor performances

When deposited by chemical vapor deposition (CVD), TiN layers must be post-treated with N 2/H 2 plasma. Metal-insulator-metal (MIM) capacitors using CVD–TiN as electrodes and Al 2O 3 as insulator are studied from both electrical and physico-chemical points of view. We verify that N 2/H 2 plasma is efficient concerning the TiN layers, while ensuring a low and uniform resistivity. However, the MIM capacitor figures of merit are impacted by the N 2/H 2 plasma, especially by the top electrode post-treatment. In particular, capacitance at 0 V has been found to increase with TiN post-treatment, as well as the quadratic linearity coefficient. As for leakage currents, the top electrode densification induces non-standard mechanism and trapping phenomenon. Finally, the dielectric relaxation is also degraded when top electrode is post-treated. Electron energy loss spectroscopy (EELS) shows that the top electrode post-treatment is associated to Nitrogen diffusion, from the TiN top electrode into the alumina. Thus, chemical interactions between top electrode and alumina layer, induced by the top electrode post-treatment, may be at the origin of such behaviours.

Study of metal organic chemical vapor deposition TiN thin films in real structures

In integrated circuits manufacturing industry, metal organic chemical vapor deposition (MOCVD) TiN thin films are widely used as barrier layers. To remove impurities such as carbon and oxygen in as-deposited films, a N2/H2in situ plasma treatment (IPT) is usually applied. In this paper, transmission electronic microscopy analysis and electrical tests were carried to study the properties of MOCVD TiN thin films in real structures, especially under different conditions of IPT and film thickness. IPT efficiency was proved to be significantly higher at horizontal planes than vertical planes due to the plasma motion perpendicular to wafer surface. This leads to an obvious difference of film thickness and structure at different locations in real structures. It was also found that IPT efficiency is sensitive with via size and aspect ratio in our electrical properties study.

Thermal stabilities of metal bottom electrodes for Ta2O5 metal-oxide-metal capacitor structure

Abstract Thermal stabilities of various metal bottom electrodes were examined by using a Ta 2 O 5 metal-oxide-metal (MOM) capacitor structure. After depositing 10-nm thick Ta 2 O 5 on metal-electrode/poly-Si, we performed rapid thermal oxidation (RTO) at 850 °C for 60 s in an O 2 ambient. A chemical-vapor-deposition (CVD) WSi 2 electrode showed satisfactory thermal stability after the RTO, while other examined electrode materials exhibited thermal degradation caused by oxidation failure or interfacial reaction between the substrate poly-Si and the Ta 2 O 5 . After post-annealing at 650 °C for 30 min (in N 2 condition) with CVD TiN top electrode, an effective oxide thickness ( T ox ) of ∼32 A and a leakage current density of ∼10 7 A/cm 2 at 1.25 V were obtained from the MOM capacitor with the WSi 2 bottom electrode. Other electrode materials, such as TiN, TiSi x , WN x , W, and Ta, were severely oxidized during the RTO in the MOM structures, and very poor capacitor properties were obtained in terms of T ox and leakage current.

Impact of Metal Gate Deposition Method on Characteristics of Gate-First MOSFET with Hf-Silicate

This paper compares metal oxide semiconductor field effect transistor (MOSFET) characteristics of TiN metal gate deposited by atomic layer deposition (ALD) and chemical vapor deposition (CVD) on Hf-based high- dielectrics. Despite many similarities between these two techniques, clear differences were found in device characteristics such as equivalent oxide thickness (EOT), mobility, dopant diffusion, and trap generation. ALD TiN results in a thicker EOT than CVD TiN due to its inherent purging cycle and higher process temperature, but it has a stronger resistance to dopant diffusion. The ALD TiN process also provides better interfacial characteristics, thus better device performance.

Kinetics of TiN Chemical Vapor Deposition Process using TiCl4 and NH3 for ULSI Diffusion Barrier Applications: Relationship between Step Coverage and NH3 Partial Pressure

TiN films were deposited by chemical vapor deposition (CVD) using NH3 and TiCl4 as the source precursors. The effect of partial pressures of TiCl4 (PTiCl4 ) and NH3 (PNH3 ) on the growth rate and step coverage quality of these TiN films was measured, revealing the growth rate of TiN films followed the Langmuir–Hinshelwood (L–H) type isotherm as a function of PTiCl4 . The sticking probability of film-forming species was estimated from the step coverage profile simulated by using the Monte Carlo method. The relationship between the sticking probability of Ti-containing species and PNH3 was investigated, revealing that the sticking probability in the 1st-order kinetic regime depended on PNH3 . The effect of NH3 on the growth kinetics could be expressed by G.R.×ρTiN=[ksKCTiCl4 /(1+KCTiCl4 )]·(CNH3 )2 in the wide range of PTiCl4 . The reason for 2nd-order reaction for PNH3 is not clear yet, but the rate equation suggests the complicated gas-phase and/or surface reaction chemistries to form TiN.

Investigations on the effects of plasma-assisted pre-treatment for plasma-assisted chemical vapour deposition TiN coatings on tool steel

Different mixtures of hydrogen, nitrogen and argon were tested for the cleaning and nitriding of cold-working, high chromium tool steel, prior to TiN deposition with the aim of improving adhesion of the TiN layer. It is well known that the condition of the substrate surface and hardening of the substrate by nitriding have a large influence on the adhesion strength of films. Good adhesion was achieved when nitrogen–hydrogen atmosphere with 40%–80% nitrogen (and 20%–60% hydrogen, respectively) was used, the best adhesion quality values were achieved (HF 1–2) with 40% nitrogen. With higher or lower fractions of nitrogen in the pre-treatment gas, adhesion was reduced. Argon addition also had negative effects on the adhesion strength. The microstructure and chemical composition of the near-interface region of the differently pretreated samples were analysed using secondary ion mass spectrometry, X-ray diffraction and light optical microscopy.

Use of average value of Langmuir probe characteristic for characterization of pulsed discharges

AbstractBased on numerical calculations a new method has been developed, which enables plasma analysis from the average value of the Langmuir probe current measured in pulsed discharge. The application of this method for characterization of a planar reactor used for plasma enhanced chemical vapor deposition of TiN and (TiAl)N hard coatings is described as an example. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Effect of Underlayer on the Via Filling and the Microstructure of the Aluminum Film in Aluminum Plug Process

The effects of the underlayer on the via filling and the microstructure of the chemical vapor deposition (CVD)-physical vapor deposition (PVD) Al films were investigated. Three types of underlayers were examined in this work: the Ti film deposited by the ionized PVD (I-PVD) method, the metalorganic CVD (MOCVD) TiN film stacked on the I-PVD Ti film, and the PVD Al film deposited on the I-PVD Ti film. Excellent via filling was achieved by employing the MOCVD TiN/I-PVD Ti or the PVD Al/I-PVD Ti as an underlayer. When only I-PVD Ti film was used as an underlayer, complete via filling was not obtained, because the CVD Al film sealed the top of vias. The CVD-PVD Al film deposited on the PVD Al/I-PVD Ti underlayer also showed excellent crystallographic texture of Al <111> and surface morphology, which is superior to those of the CVD-PVD Al film deposited on the MOCVD TiN/I-PVD Ti underlayer.