ICMCTF2011 Session BP: Symposium B Poster Session

Thursday, May 5, 2011 5:00 PM in Town & Country

Thursday Afternoon

Time Period ThP Sessions | Topic B Sessions | Time Periods | Topics | ICMCTF2011 Schedule

BP-2 Oxygen Impurities in Ti-Si-N System are Hindering the Phase Segregation, Formation of Stable Nanostructure and Degrading the Cutting Performance of Tools Coated with the Nanocomposites
Stan Veprek, Maritza Veprek-Heijman (Technical University Munich, Germany); Mojmir Jilek (SHM Ltd., Czech Republic); Miroslav Piska (Brno Technical University, Czech Republic); Xianting Zeng (Singapore Inst. of Manufacturing Technology, Singapore); Andreas Bergmaier (Universität der Bundeswehr, Germany); Q.F. Fang (Chinese Academy of Sciences, China)
We have shown earlier, that oxygen impurities of >3000 atomic ppm strongly degrade the hardness of the nc-TiN/a-Si3N4 nanocomposites. Here we show that such impurities also hinder the phase segregation and formation of stable and strong nanostructure consisting of 3-4 nm size TiN nanocrystals "glued" together by about 1 monolayer thick interfacial Si3N4 -like layer, thus apparently stabilizing the solid solution at high temperature of ≥900°C, which has been reported by other researchers. At the impurity content of only few hundred at. Ppm, the segregation is completed, and stable nanostructure formed at temperature of ≤550°C, whereas with increasing oxygen impurity content the temperature needed for the segregation strongly increases. By decreasing the impurity content from 2000-3000 ppm down to about 700-1000 ppm in an industrial PVD coating unit, the life time of cutting tools has been increased by about a factor of ≥2. The results to be presented will underline the need for the improvement of the purity of the nanocomposite coatings applied in the industry, as well as those used for fundamental studies in academia.
BP-3 Structural and Mechanical Properties of Multilayered ZrN/CrAlN Coatings Synthesized by a Cathodic-Arc Deposition Process
Tung-Han Yang, Yin-Yu Chang, Chia-Yuan Hsiao (Mingdao University, Taiwan)
Multilayered ZrN/CrAlN coatings with superlattice structure were deposited by using cathodic-arc evaporation with plasma enhanced duct equipment. Zirconium and Cr0.3Al0.7 alloy (30/70 at.% ratio) cathodes were used for the deposition of ZrN/CrAlN coatings. During the coating process of multilayered ZrN/CrAlN, ZrN was deposited as an interlayer. The total cathode current of both Zr and CrAl targets was controlled at 140 A. With different cathode current ratios (I[CrAl]/I[Zr]) of 0.75, 1.0, and 1.33, the deposited multilayered ZrN/CrAlN coatings possessed different chemical contents and periodic thicknesses. The effect of alloy content (Al, Cr, and Zr) and layer thickness ratio of CrAlN/ZrN on the mechanical properties of ZrN/CrAlN coatings were investigated. From the X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM) analyses, the crystal structure of CrAlN layer in the ZrN/CrAlN multilayers has a metastable cubic lattice structure, matching coherently with the ZrN layer. The periodic thickness and layer thickness ratio of CrAlN/ZrN increased with I[CrAl]/I[Zr] cathode current ratio. Hardness and Young’s modulus of the deposited coatings were determined by nano-indentation. The multilayered ZrN/CrAlN coating with layer thickness ratio of CrAlN/ZrN=1.4 exhibited the highest H3/E*2 ratio value of 0.338 GPa, indicating the best resistance to plastic deformation, among the studied ZrN, CrAlN and multilayered ZrN/CrAlN coatings.
BP-4 Evaluation of Depth Profile of Residual Stress in a TiN Thin Film
Ching-Ju Lan, Jia-Hong Huang, Ge-Ping Yu (National Tsing Hua University, Taiwan)
Residual stress plays an important role on structure and properties of thin films. Most measurement methods determine the average residual stress in thin film, but not the depth profile of stress along thickness. In this study, the depth profile of residual stress of a titanium nitride (TiN) thin film was established using grazing incident X-ray diffraction (XRD) accompanied with calculation using layer-by-layer method. TiN films were deposited by unbalanced magnetron sputtering (UBMS). Laser curvature technique was used to measure the residual stress and conventional sin2ψ XRD method was employed to determine the strain components in the thin films. By combining these two techniques, the X-ray elastic constants (XECs), Young’s modulus and Poisson’s ratio, of the thin films can be obtained. A modified sin2ψ method, cos2αsin2ψ method, with asymmetric Bragg–Brentano (B-B) geometry using grazing incident X-ray was adopted to measure the residual stress at different depth. The cos2αsin2ψ method has the advantages of increasing diffraction volume and reducing anisotropic effect of thin film specimens. The XECs determined by the X-ray and laser curvature combining technique can be applied in the cos2αsin2ψ method to obtain the residual stress at different depth by appropriately changing the grazing angles γ (α = θo-γ, where θo is the diffraction angle of the chosen diffraction plane.). Then simplified layer-by-layer method was used to establish the depth profile of residual stress in the TiN thin film. The stress gradient in the thin film was compared with that modeled by Finite element method.
BP-5 Measurement of Fracture Toughness on TiN Thin Films
An-Ni Wang, Ge-Ping Yu, Jia-Hong Huang (National Tsing Hua University, Taiwan)
This research was in an attempt to develop a new method without applying external stress for measuring fracture toughness of transition metal-nitride (TMN) thin films. TMN thin film was selected to be the model material, owing to its well-characterized mechanical properties and appropriate elastic isotropy. At present, there has been no standard methodology or test procedure for assessing the fracture toughness of hard coatings. Previous literatures have proposed various approaches on the measurement of fracture toughness, which can be divided into two categories: stress based or energy based. However, those methods need to design special specimen geometry because of the requirement in producing valid pre-cracks, and thus the substrate effect cannot be eliminated. In addition, special stages are often needed to externally apply stress, which increases the difficulty of the test methods. TiN thin films deposited by PVD methods normally have high residual stress which can be controlled by adjusting deposition parameters and measured nondestructively. Instead of externally applying stress, the residual stress was utilized in the assessment of fracture toughness. From Griffith 's criterion, energy stored in the film due to elastic mismatch strain can be released by the formation of cracks. The difference in stress states before and after crack initiated was used to evaluate the average energy release rate, from which fracture toughness can be calculated by fracture mechanics. This method involved residual stress measurement by laser curvature technique and elastic modulus measurement by nanoindentation according to ISO 14577-4:2007. The Poisson’s ratio of single-crystal TiN was used. The results were compared with those obtained from other techniques and the strong and weak points of this method were discussed.
BP-6 Nanocomposite PVD Coatings for Milling of Hardened Steels and Cast Ion
Philipp Immich, Uwe Schunk, Uwe Kretzschmann (LMT Fette, Germany)
The ever increasing demand for higher productivity in manufacturing requires advanced PVD hard coatings. The coatings can be tailored to exhibit for example higher hardness and / or enhanced oxidation resistance and good adhesion. One such way to influence coating properties is addition of silicon to a conventional TiAlN coating made by arc PVD. As silicon cannot be easily incorporated into the cubic lattice a so-called nanocomposite coating with special properties is formed. The silicon content of coating can be varied in a wide range resulting in different mechanical properties and coating structure. The properties of the deposited films were analyzed by common thin film techniques revealing hardness, Young´s modulus and coating adhesion. As a result from theses investigations a nanocomposite coating with excellent coating properties like a high hardness and a good adhesion was developed and deposited onto special carbide shank tools. These tools are tested in cutting experiments in, hardened steel (> 54 HRC) and cast iron, comparing conventional state of the art coatings and the developed nanocomposite coating. The developed coating shows an increase of tool with a significant reduction in the tool wear during the milling operation.
BP-7 An Experimental Trial of Prediction and Control Technology of Film Properties by a Numerical Model in Vacuum Vapor Deposition
Jae-In Jeong, Ji-Hoon Yang, Hye-Sun Park, Seung-Hyun Jang (Research Institute of Industrial Science and Technology, Korea)

In vacuum vapor deposition techniques such as physical vapor deposition (PVD) and chemical vapor deposition (CVD), the film properties are strongly depending on the process conditions. It is customary and is considered to be reasonable that the deposition system be controlled by the ordered sequence with pre-determined parameters. The process conditions were fixed by the operator and the values are determined prior to deposition. After the coating, the film properties are evaluated and then the process conditions are changed to obtain optimum film properties. Generally, this optimization process is troublesome and it takes much time to have optimum process conditions, especially for complex films having multilayer or multistep structures with so many parameter values.

In this study, it has been tried to predict and obtain best coating quality by a numerical model. The model was based on the data obtained from the experimental values and interpolation and/or extrapolation method was employed. The synchronization of the system, i.e., the unification of the difference between one system and the other was fulfilled on a trial basis by diagnostic equipments such as Langmuir probe and/or Optical Emission Spectroscopy (OES).

The first preliminary trial was manifested with TiN coating on the stainless steel plate. The brightness was measured with two variables of nitrogen flow rate and substrate temperature. The numerical equation was derived from the measured data according to the variation of the two variables. The interpolation method was used to obtain the best curve fitted to derive the numerical equation. With this equation the system was operated by inputting the user-defined brightness value. The hit rate which signifies the accuracy of brightness prediction turned out to be more than 70%.

BP-8 The Effect of Laser Annealing on the Crystal Structure of Magnetron Sputtered Alumina Thin Films
Husam Abu-Safe (Lebanese American University, Lebanon); Fuad Rawwagh (Yarmouk University, Lebanon); Malek Tabbal (American University of Beirut, Lebanon); Mohammad Roumie (the National Council for Research, Lebanon)

The effect of laser annealing on the crystal structure of alumina thin films has been investigated. The crystal structure of the films is basically determined by the deposition conditions during the process. Gibbs free energy stored in the various films is changed with an external thermal deposition. The thermal deposition is established using a cw Ar ion laser system. Within certain thermal limits, an exothermic process in the crystal planes is activated leading to partial release of the internal energy in the fabricated films. The crystal structure of the processed films is “healed” to the minimum energy status which will lead to the alpha phase. Three sets of alumina thin films have been prepared for this study using an inverted cylindrical magnetron sputtering system with an unbalanced magnetic field. All sets were laser annealed at different energy densities and annealing times. The crystal structure before and after annealing is investigated and the stoichiometry of the fabricated films are reported.

BP-9 Wear and Corrosion Properties of TiSiN and TiSiN/CrN Coatings by Cathodic Arc Deposition
Wei-Yu Ho, Ching-Hui Hsieh, Yin-Yu Chang, Chi-Lung CHang, Chen-Jui Wu (MingDao University, Taiwan)

In a thermodynamically favored process, TiSiN ternary system segregates into the two binary compounds which are usually formed by nanocrystalline TiN embedded in a matrix of amorphous SiNx. The influence of the Si content in the coatings on the

mechanical properties and tribological behaviors of the TiSiN coatings were systematically studied by several researches. Nanoindentation result shows that the hardness and Young's modulus of the TiSiN coatings increase with increasing Si content in the coatings. TiSiN coatings exhibit an increase in the friction coefficient with an increasing Si content in the coatings.

The advantage of TiSiN coating is feasible for machining applications owing to its dense, highly adhesive, high hardness properties. However, TiSiN coating, in general, shows poorer performance than TiN in the case of low sliding speed or interrupted cutting process due to its brittleness and high friction coefficient. Previous study shows that TiSiN/TiAlN were dependent on lamellae thicknesses in film structure, resulting in improved mechanical, wear and corrosion properties. The similar study presented that the mechanical and tribological property can be improved by the design of multilayered TiSiN/CrN coating. It showed the multilayered TiSiN/CrN coating possessed excellent resistance to plastic deformation as compared with the monolayered TiSiN. However, the effect of the deposition parameters on the properties of TiSiN/CrN coating was not studied in combination of bias voltage and multilayer structure.

In this study, a monolayered TiSiN and a multilayered TiSiN/CrN coatings deposited with different bias voltages were synthesized by a cathodic arc deposition process. TiSi (80/20 at.%) and chromium targets were used for the deposition of TiSiN and multilayered TiSiN/CrN coatings. The performance of the coating was evaluated by microstructure, ball-on-disc wear test and corrosion test.

BP-10 Properties of Carbon-Based Coatings on Injection Mold Steel Prepared by Nitriding and PCVD Hybrid Process
K.H. Lee, J.W. Park, K.S. Park, D.W. Kim (Research Institute of Industrial Science and Technology, Korea)

Industrial application of carbon-based coatings has been paid attention owing to their excellent mechanical properties, such as high hardness, elastic module and low friction coefficient. In recent, exciting ongoing researches try to deposit carbon-based protective film on automobile engine parts, tools and molds taking into account not only high hardness, but also solid lubricating properties. On the other hand, it is well known that carbon-based coatings have a low adhesion to metal surface due to their high internal stress. It is a big problem to apply on automobile, tool and mold industrials. It is also difficult to increase a film thickness.

In this study, carbon-based coatings were prepared on injection mold steel and silicon wafer by plasma chemical vapor deposition after plasma nitriding in the same chamber as continues process. Plasma nitriding process was performed under 0.1 torr of pressure using N2 and H2 gases with a pulsed DC bias voltage of -400V at 400°C for 3 hours. Carbon-based coatings were fabricated under pressure of 0.05 and 0.1 torr with CH4 gas, temperature of room temperature, 100°C and 150°C, and bias voltage of - 400V, -500V and -700V, respectively. In case of nitriding and PCVD hybrid process, the temperature of chamber was controlled to test condition after plasma nitriding process. Hardness was evaluated by nanoindentation and low load vickers hardness tests. Friction coefficients against a SUJ2 (JIS) steel ball were measured by tribometer (ball-on-disk) with load of 5 N under humidity of 56 to 76%. Chemical bonding states were investigated by X-ray photoelectron spectroscopy and Raman spectrometry. Surface morphology was observed by atomic force microscopy.

Several types of samples were prepared. The sample (#1) of plasma nitriding without carbon coating is showed above two times higher hardness than the sample without substrate (KP4). Hardness for the sample(#2) prepared by PCVD carbon coating shows 1224 Hv. The sample(#3) prepared by nitriding and PCVD hybrid process with carbon coating shows lower hardness than that of #2. It is considered that hardness is affected the nitrided substrate owing to overly thin film thickness. Friction coefficient of samples showed about 0.4 for sample #1, 0.3 for sample #2, 0.15 for sample #3. Friction coefficient for sample #2 shows the lowest in initial stage, but it is gradually increased to 0.3, and then stabilized to the end of the test. It is considered that coating delamination occured from substrate. This study will be discussed on the properties of carbon-based coatings injection mold steel prepared by hybrid process, and designing layers and complex materials.

This work was financially supported by the grant from the Industrial Strategic Technology Development Program, Republic of Korea.
BP-13 Tetrahedral Amorphous Carbon Tetrahedral Amorphous Carbon Deposited by Filtered Cathodic Vacuum Arc Bombarded by Argon Ions
Edison Motta, Gustavo Viana, Douglas Silva, Andressa Cortês, Francisco Marques (Universidade Estadual de Campinas, Brazil)

The effect of argon bombardment in tetrahedral amorphous carbon (ta-C) deposited by the filtered cathodic vacuum arc (FCVA) technique is investigated. The films were prepared with 5 ms current pulses of 190 A at a frequency of 3 Hz. The deposition substrate was polarized in the 0 to - 500 V bias voltage range. The density of the films, also determined by RBS, was in the 2.5 to 3.0 g/cm3 range, depending on the substrate bias voltage. The stress of the films (up to about 10 GPa) was determined by the bending beam technique. Nanohardness measurements were performed indicating that the films prepared in the 100-200 bias voltage is about 50 GPa. Argon gas was incorporated in a series of films using an ion gun source to simultaneously bombard the films with a beam of argon ion with energy in the 0-180 eV range. Argon concentration in the films was determined by RBS measurements. A study of argon effusion, realized from room temperature up to 1000 oC, shows that the structure of the films depends on the bombardment energy of the argon ions. It was observed that the stress reduces significantly as a function of the effusion temperature. Raman measurements were used to investigate the structure of the films as a function of the bias voltage and annealing temperature.

BP-14 Thermal Stability of V-Al-C Thin Films Grown by DC Magnetron Sputtering Using a Multi-component Target
Yan Jiang, Riza Iskandar, Tetsuya Takahashi, Jie Zhang, Moritz to Baben, Mayer Joachim, Jochen Schneider (RWTH Aachen University, Germany)

V-Al-C thin films were deposited on Al2O3 (11-20) substrate at 500°C by DC magnetron sputtering using a hot-sintered multi-component target with 2:1:1 MAX phase-like composition. TEM and XRD data suggest that hexagonal Al-containing vanadium carbide solid solution was formed. The films exhibited a strong basal plane texture. The lattice parameter of the hexagonal solid solution was dependent on annealing time and temperature: the c lattice parameter of V2(Al)C decreased by 3.5 % after annealing for 1 hour at 750°C as compared to the as deposited film. Meanwhile, the formation of V2AlC MAX phase was observed at 650°C and a phase-pure V2AlC thin film was obtained at 850°C. Previously, the formation of phase-pure V2AlC thin films was reported at 750°C, suggesting that surface diffusion is affecting the structure evolution of V2AlC thin films at low substrate temperatures.

BP-15 The Effect of Composition on the Structure, Mechanical Properties, and Thermal Stability of Sputter Coated Ternary Chromium-Molybdenum-Nitride Coatings
Yujiao Zou (University of Alabama, Birmingham)

Hard nitride coatings of the group VIB transition metals are increasingly used in a wide range of tribological applications to improve performance and to extend the life of metal cutting, drilling, and forming tools, as well as bearings and various machine parts. Among the nitrides of group VIB elements, binary CrN and MoN have been well studied. CrN has excellent corrosion resistance under severe environment conditions, superior oxidation resistance, and good wear resistance; MoN has been found to have many unique physical and mechanical properties such as high hardness, low solubility in non-ferrous alloys and low friction, etc. As a result, ternary Cr-Mo-N coatings could have superior properties tailored through appropriate combinations of CrN and MoN.

We have prepared ternary Cr-Mo-N coatings with different compositions on Si wafers by using a dual rf-magnetron sputtering system with Cr and Mo targets and nitrogen as reactive gas. The metal target bias voltages were varied from -500 V to -900 V which allowed to preparing the ternary layers with Cr/Mo ratios in the range from 1/3 to 3/1. Binary CrN and MoN coatings were also prepared under similar conditions for comparison. The resulting coatings had up to 1.8 micron thickness and were well adherent to the substrate. The hardness, surface morphology, microstructure, and composition were studied by nanoindentation, SEM, AFM, XRD, and XPS, respectively. All coatings were smooth and nanocrystalline with mean grain size 15-20 nm and showed single XRD-observable phase with the characteristic XRD peaks varying between those of CrN and MoN depending on the composition. The hardness and Young’s modulus were found in the range of 9.0 - 16 GPa and 120 - 215 GPa, respectively, with larger values observed for Mo-richer layers. To investigate the effect of thermal treatment on the microstructure and mechanical properties, the samples were annealed in air at temperatures up to 700 °C for 1 hour. The thermal stability of the coatings was found to increase with a larger amount of Cr in the ternary system. The MoN coating was completely oxidized after annealing in air at 600 °C for one hour, whereas the ternary Cr-Mo-N coatings with Cr content more than 75 at.% survived under up to 700 °C without cracking or delamination. The final result of the annealing was Cr2O3 as main crystalline phase. However, the hardness was increased at intermediate annealing temperatures while the coatings maintained their initial structure.

This work has been supported by the U.S. National Science Foundation Grant #DMR-0806521 and the Regional Council of Burgundy, France.

BP-16 Oxidation Resistance and Microhardness of (Ti,Al,Si)N/(Cr,Al,Y)N Nano-Multilayered Film
Takanori Mori, Keita Yoshiwara, Mari Takahashi (Keio University, Japan); Toshiyuki Watanabe (Kanagawa Industrial Technology Center, Japan); Tetsuya Suzuki (Keio University, Japan)

In the field of hard coatings, oxidation resistance and high hardness of the coatings are among the main concerns. Incorporation of yttrium into ceramics has become an attractive method to impart improved mechanical and chemical properties to the ceramics. Multilayered structure of the coatings has also attracted much attention as an effective approach to obtaining improved properties. We have reported superior oxidation resistance of (Cr,Al,Y)N compared to (Cr,Al)N and improved mechanical and chemical properties of (Ti,Al,Si)N/(Cr,Al)N multilayered films.

In this study, we synthesized nano-multilayered (Ti,Al,Si)N/(Cr,Al,Y)N films and investigated their oxidation resistance and microhardness. The films were deposited on Si or WC-Co substrates by cathodic arc ion plating (AIP) method using TiAlSi and CrAlY alloy targets. The two nitrides, (Ti,Al,Si)N and (Cr,Al,Y)N, were deposited alternately on the substrates and the multilayer period was controlled by varying the rotation speed of the substrates from 2.5 to 5.0 rpm. Microstructure of the films was investigated under scanning electron microscope (SEM) and transmission electron microscope (TEM). The microhardness was measured using a conventional micro-Vickers hardness tester. For the evaluation of the oxidation resistance, X-ray diffraction (XRD) and glow discharge optical emission spectrometry (GDOES) were performed to identify oxide layers of the films before and after annealing at 900ºC and 1000ºC for 1 hour.

The microhardness of (Ti,Al,Si)N/(Cr,Al,Y)N film was about 33 GPa, which was higher than the value calculated based on the rule of mixtures. Some metal oxide peaks were observed for (Ti,Al,Si)N or (Cr,Al,Y)N films annealed at 900ºC and 1000ºC, while no peaks indicating metal oxide were observed for the (Ti,Al,Si)N/(Cr,Al,Y)N films. These results demonstrate that the (Ti,Al,Si)N/(Cr,Al,Y)N multilayered films possess highly improved oxidation resistance with higher hardness compared to monolayer films, which indicates that the multilayered films presented here could be a suitable candidate for cutting tools.
BP-17 Evaluation of Ti3SiC2 Coatings Deposited by HTCVD from Methyltrichlorosilane and Titanium Tetrachloride
Sorana Luca, Rachel Martin, Pierre-Olivier Robert, Didier Pique (ACERDE, France); Magali Morais, Elisabeth BLANQUET, Michel Pons (SIMAP, France)

MAX phases received great interest the last years due to a combination of metallic and ceramic properties: they are very good thermal and electrical conductors and are easily machinable. They exhibit a great interest for electrical contacts and also for machining tools.

Compared to PVD techniques (such as magneton sputtering or PLD) which are largely adopted for MAX phases thin films deposition, it seems to be more difficult to obtain single –phase Ti3SiC2 by CVD techniques. Few studies on the direct deposition of Ti3SiC2 coating by CVD using TiCl4 –SiCl4-CCl4 (or CH4)-H2 system are reported. Ti3SiC2/SiC multi layer coatings were fabricated by reactive CVD (RVCD) using the reaction between a gas mixture (TiCl4/H2) and solid SiC.

In this paper we present the first study on the fabrication of the Ti3SiC2 MAX phase coatings by High Temperature Chemical Vapor Deposition (HTCVD). Experiments have been conducted (using Methylchlorosilane (MTCS) and Titanium Tetrachloride (TiCl4) as reactants (with hydrogen as carrier gas) from 1200°C to 1350°C, with different values of TiCl4 to MTCS ratio and of the dilution coefficient α = Q(H2)/(Q(MTCS) + Q(TiCl4)

Thermodynamic calculations performed on this system in the temperature range are compared to the experimental results.

The composition of the deposited films was analysed using X-ray diffraction technique and WDS (Castaing microprobe). SEM (Scanning Electron Microscopy) and TEM (Transmission Electron Microscopy) were used to observe the coatings microstructure. It was found that nearly pure Ti3SiC2 was deposited at 1300°C with a high dilution coefficient of the reactants in hydrogen.

BP-18 Annealing Effect on Microstructure and Mechanical Properties of Titanium Nitride Thin Film
Shiuh-Chuan Her, Wei Nan Lin, Cheng-Lin Wu (Yuan Ze University, Taiwan)
Titanium Nitride (TiN) coatings with high surface hardness, good wear and corrosion resistance, low friction coefficient have been widely used in many applications such as a hard coating of cutting tool, a diffusion barrier layer. In this work, TiN thin films were deposited by D.C. magnetron sputtering process on SUS 304 steel substrate. The effects of postdeposition annealing on the microstructure and mechanical properties of TiN thin films were studied in details using atomic force microscopy, potentiostat and nanoindentation test. The TiN films were annealed at temperatures ranging from 100oC to 300oC in steps of 100oC by using thermal annealing equipment in air for 80 minutes. The thicknesses of the films measured by surface profiler were decreased from 181nm to 137nm as the annealing temperatures increasing from 100oC to 300oC. The surface roughnesses of the films observed by atomic force microscopy were decreased from 3.83nm to 2.43nm as the annealing temperatures increasing from 100oC to 300oC. The corrosion rates of the films measured by a potentionstat in 0.5 molar H2SO4 solution were decreased from 8.57x10-2 mmPY to 4.59x10-2 mmPY as the annealing temperatures increasing from 100oC to 300oC. The increase in the corrosion resistance is attributed to the increase in hardness and modulus of the film with the annealing temperature. Atomic force microscopy image of the film revealed fine-grained morphology for the TiN annealed at higher temperature. Experimental results showed that the mechanical properties of TiN films could be significantly improved by the annealing process. The control of annealing process is proved to be critical for the improvement of the TiN film performance.
BP-19 Texture and Magnetic Properties of Electrodeposited FePd Films
Hung-Pin Lin, Jui-Chao Kuo (National Cheng Kung University Taiwan)

The preferred orientation (texture) and magnetic properties of electrodeposited FePd films were investigated using electron back-scatter diffraction (EBSD) and vibrating sample magnetometer (VSM). Fe-Pd films were electrodeposited on brass and Cu (001) substrates using an alkaline electrolyte which was composed of Fe sulfate, Pd chloride and 5-sulfosalicylic acid and ammonium sulfate. The potential for the electrodeposition process was varied from -0.9V to -1.1V. The chemical compositions of the deposited films were analyzed using EDS, and the crystallographic structures of deposited films were characterized using XRD, TEM and EBSD.

BP-20 Effect of Oxygen in Aerosol Assisted Chemical Vapor Deposition of TiO2 Using Titanium tetra-iso-propoxide/acetylacetone Solutions.
Francis Maury, Dan Duminica (CIRIMAT CNRS-INPT-UPS ENSIACET, France)
Functional titania thin films have been deposited on various substrates under atmospheric pressure to produce self-cleaning surfaces by aerosol assisted chemical vapor deposition (AACVD). Titanium tetra-iso-propoxide (TTIP) was used as titanium source in solution with acetylacetone (acac). The influence of an oxygen partial pressure has been investigated in the temperature range 723-923 K. The growth rate increases by 10-40 % in presence of O2 using a 1.5 M TTIP/acac solution. The films grown at 773 K on Si and glass substrates in presence of O2 using pure TTIP are single phased (anatase structure) while those synthesized without O2 exhibit a low proportion of rutile. By contrast, always at 773 K, the presence of O2 favors the formation of rutile for the films grown on steel. Without addition of O2 the C content of the films is high and it was found to increase with the deposition temperature. It essentially originates from the acac solvent. The C contamination decreases in presence of O2. The by-products of the growth process were analyzed by IR and NMR to elucidate the role of O2 in the mechanism. When oxygen partial pressure is used the formation of CO2 at the expense of propene gives evidence for a mechanism of combustion in addition to pyrolysis. The hydrophilicity of the layers increases with the O2 partial pressure. The wettability is not improved by UV irradiation when acac solvent is used in the AACVD process likely because the photocatalytic behavior of these layers is not efficient.
BP-21 Cylindrical Magnetrons Sputter Deposition of Ta on Carbon Steels using DC Magnetron Sputtering, HIPIMS and MPPMS
Ronghua Wei (Southwest Research Institute); Sabrina Lee, Michael Riley (US Army ARDEC Benet Labs)

In this paper, we present the results from a study in which Ta was sputter deposited on the inner surface of tubes of carbon steels using various cylindrical magnetron sputtering processes. The inner surface of cylinders often requires protection from erosion and corrosion from high temperature chemicals. Currently electroplated Cr is applied for protection. To reduce and eventually eliminate electroplating for this application, cylindrical magnetron sputtering (CMS) driven by a DC power supply has been pursued for a number of years. Pulsed DC power supplies that promise to deliver extremely high peak power have been used in conventional planar magnetron sputtering, and the resultant films are proven to be significantly better in microstructural characteristics and tribological performance than those produced using standard DC power supply. In the current study, three sputtering methods were used to deposit Ta on the inner surface of cylinders (100 mm in diameter by 300 mm long) made of carbon steels 1018 and A723. These three sputtering methods include DC magnetron sputtering (DCMS), high power impulse magnetron sputtering (HIPIMS) and modulated pulsed power magnetrons sputtering (MPPMS). Carbon steel 1018 was used for the initial study; then thick Ta coatings were deposited on A723 steel. After the deposition, SEM, XRD, AFM, microhardness, Rc indentation, and scratch test were performed to understand the coating microstructure including the phase formation and transformation, and mechanical properties including the coating adhesion and internal stress. It has been observed that all coatings produced by these three techniques are dense with fairly good adhesion. The coating internal stress is similar for both DCMS and HIPIMS and increases with the coating thickness. Under the same average power, the HIPIMS process resulted in a similar deposition rate as the DCMS, in contradiction with the results obtained in the planar magnetron sputtering. This paper will present the detailed microstructural and mechanical characterization results.

BP-22 Effects of Nitrogen Ratio on Resistive Switching Characteristics of Titanium Oxynitride Thin Films by DC Reactive Magnetron Sputtering
Li-Chun Chang, Kang-Hua Chang (Ming Chi University Of Technology, Taiwan); Keng-Hao Liu (Chang Gung University, Taiwan); Hsin-Jung Tsai, Wei-Zhong Wang (Ming Chi University of Technology, Taiwan)

Ru/TiNxOy/Ru structures were prepared by dc magnetron sputtering. The resistive switching characteristics of Ru/TiNxOy/Ru structures were investigated as a function of nitrogen partial pressure during TiNxOy deposition. Reproducible resistive switching characteristics were observed in TiNxOy thin films deposited at N2/O2 ratios of 2.0, 2.5, and 3.0. The conduction mechanisms in high and low resistance states are dominated by space-charge-limited conduction and ohmic behavior respectively, which suggests that resistive switching behaviors in such structures are related to filament formation and rupture. It is also found that the reset current decreased as nitrogen partial pressure increased, due to the variation of oxygen vacancy concentration in the TiNxOy thin films.

BP-23 Plasma Diagnostics for Pulsed-dc Plasma-Polymerizing Para-Xylene using QMS and OES
Chia-Man Chou (Feng Chia University & Taichung Veterans General Hospital, Taiwan); Chih-Cheng Chuang, Chia-Hao Lin (Feng Chai University, Taiwan); Chi-Jen Chung (Central Taiwan University of Science and Technology & Taipei Medical University, Taiwan); Ju-Liang He (Feng Chai University, Taiwan)
Following the successful demonstration of our work on plasma-polymerized para-xylene (C8H10, C8H9, C7H7, C6H5, CH3, H2(H3C -C6H4-CH3, PPX) thin films for biomedical applications in our previous study, we used quadrupole mass spectrometry (QMS) and optical emission spectrometry (OES) to identify active species in plasma space in this study, so as to link process parameters (para-xylene monomer flow rate, fp, and pulse frequency of the power supply, ωp, in particular) with film microstructure and properties. In QMS analysis, C8H10, C8H9, C7H7, C6H5, CH3, H2 and H were found (with their concentration increased as a function of fp) in plasma space, while the molecules CxHy (2 ≦ x ≦ 5), bond-broken from the benzene ring, were not detected due to their prompt condensation into solid film. By increasing ωp (equivalent to the increased power density), significant fragmentation occurred to the larger molecular species (C8H10, C8H9, C7H7, C6H5). This accounted for the films that were obtained at low fp and high ωp, which exhibited a long-chain alkene inorganic feature, and consequently less water repelling. Moreover, the increased Hα and H2 at an increased ωp detected by OES in plasma space indicated that the recombination of active species (in plasma) and dehydrogenation reaction (with the condensed film) prevailed. The dehydrogenation effect explains the decreased film growth rate as well as the decreased surface roughness of the films deposited at an increased ωp.
BP-24 Corrosion Evaluation of Ductile Iron Duplex-Treated by Electroless Ni-P and TiAlZrN Coating
Cheng-Hsun Hsu (Tatung University, Taiwan); Chung-Kwei Lin (Feng Chia University, Taiwan); Kai-Lin Chen, Y.-H. Chang (Tatung University, Taiwan); C.-Y. Su (National Taipei University of Technology, Taiwan)

This study utilized two surface techniques consisting of electroless nickel (EN) and arc ion plating (AIP) to treat the ductile iron substrates. That is, EN was first used as an interlayer, and then TiAlZrN film was coated on superficial by using the AIP method. Coating morphology, structure, and adhesion were analyzed, as well as polarization and immersion tests were also performed for understanding the effect of the duplex coatings on corrosion behavior of ductile iron. The results showed that EN is an amorphous structure, while the TiAlZrN film is a multilayer type. Ductile iron after the monolithic EN or TiAlZrN coating has better corrosion resistance as compared with uncoated one. In particular, a combination of EN/TiAlZrN duplex coatings not only increases the adhesion, but also evidently improves the corrosion resistance of ductile iron in 3.5 wt% NaCl and 10 vol.% H2SO4, respectively.

BP-26 Microstructures and Mechanical Properties of Nano-Structured TiAlCN/Amorphous Carbon Films
Wen-Hsiung Wu, Yin-Yu Chang, Ho-Yi Kao (Mingdao University, Taiwan)
Ternary TiAlN and TiAlCN/amorphous carbon(a-C) coatings with different carbon contents were synthesized by a cathodic arc evaporation process, equipped with a plasma enhanced duct, using AlTi (25/75 and 50/50 at. % ratio) alloy targets. Reactive gas (N2) and CH4 activated by the AlTi alloy plasma in the evaporation process was used to deposit the TiAlCN/a-C coatings. At a total gas pressure of 2.0 Pa, a mixture of reactive N2 and CH4 with different CH4 flow rate from 0 sccm to 25 sccm was introduced into the chamber to form the TiAlCN/a-C coating with different carbon contents. The crystallographic texture of the deposited coatings was characterized using glancing incidence X-ray diffraction (GIXRD), while the structure was studied using field emission scanning electron microscopy (FESEM) and cross-sectional transmission electron microscopy (TEM). The characteristics of composition and chemical binding of the deposited films were identified by X-ray photoelectron spectrometry (XPS). It showed the nano-grain structure transformation by the addition of carbon to TiAlN films. A nanocomposite structure of coexisting metastable hard TiAlCN crystallites and amorphous carbon phases was found in the coatings, those possessed smaller crystallite sizes than the ternary TiAlN film. Scratch tests and Rockwell indentation were performed to determine the interfacial adhesion between substrate and TiAlCN/a-C films. Mechanical properties, such as hardness and elastic modulus, were measured by a nano-indentation test. Tribological investigations were performed by using a ball-on-disk test. The effects of carbon concentration on the microstructure and mechanical properties of TiAlCN/a-C coatings were studied.
BP-27 The Effect of Bias on The Structure and Property of (Ti,Zr)N Thin Film Deposited by Radio Frequency Magnetron Sputtering
Yu-Wei Lin (Instrument Technology Research Center, Taiwan); Jia-Hong Huang (National Tsing Hua University, Taiwan); Ge-Ping Yu (National Tsing Hua University, Taiwan, Republic of China)
Nanocrystalline thin films of (Ti Zr)N were deposited by radio frequency magnetron sputtering based on our previous optimum coating conditions for TiN and ZrN. The effect of bias on the microstructure and properties of (Ti Zr)N film was investigated . The negative bias voltage ranging from –20 V to –120 V was applied to the substrate. The film thickness measured by SEM ranges from 588 to 1827 nm. The grain size of (Ti Zr)N thin films can be obtained from the FWHM of (111) or (200) peaks using Scherrer equation, the grain sizes of the nanocrystalline (Ti Zr)N are about 10~18 nm. The packing factors and N/(Ti,Zr) ratios of the (Ti Zr)N films were obtained byRutherford backscattering spectroscopy (RBS). The packing factor of (Ti,Zr)N films relate with the substrate bias, the increase of the packing factor was from 0.83 to 1 with low substrate bias ranging from –20V to –60V. Hardness of the (Ti,Zr)N films was measured with the nanoindenter. Hardness of (Ti,Zr)N films was ranged from 30.2 ~ 37.8 GPa, increasing with increasing packing factor. Electrical resistivity decreased with the negative bias from 20 V to 60 V and then increased with the negative bias from 60 V to 120 V. Proper substrate bias may enhance the mobility of the adatoms to stable site on the substrate surface, it will decrease the resistivity and increase the crystalline quality. However, a high substrate bias may induce radiation damage to the growing film and produce lattice defects.
BP-29 Multi Pulse Modulated Pulse Power (MPMPP) Magnetron Sputtering of the Structural Modulated Hard Tribological Coatings
Jianliang Lin, John Moore (Colorado School of Mines); William Sproul (Reactive Sputtering, Inc.); Sabrina Lee (US Army ARDEC Benet Labs)
The multi pulse modulated pulse power (MPMPP) magnetron sputtering is a new form of the modulated pulse power (MPP) magnetron sputtering technique. In the MPMPP technique, two different high power pulses, which generate different peak target powers and currents on the same target, are fast switched alternately by the MPP generator for different durations. With this approach, thin films with periodical structure modulation in the nanometer range can be obtained. In this study, CrN coatings have been deposited by sputtering of a metal Cr target in an Ar and N2 gas mixture in a closed field unbalanced magnetron sputtering system using the MPMPP technique as the technical example. The films deposited by direct current magnetron sputtering (DCMS) and single pulse MPP techniques were used as the baseline. The microstructure and properties of the films were characterized using x-ray diffraction, transmission electron microscopy, nanoindentation, and ball-on-disk wear tests. The MPMPP CrN films exhibited decreased grain size and increased density as compared to the DCMS and single pulse MPP CrN films . The Structure and properties of the MPMPP CrN films depended on the durations of different pulse shapes, which determine the modulation period of the nanolayered structure. The MPMPP CrN films exhibited high hardness (27-30 GPa), significantly improved H/E ratio (>0.9) and wear resistance (low coefficient of friction of 0.23) as compared to the DCMS and single pulse MPP CrN coatings.
BP-31 Multilayer Diamond Coatings for the Machining of Aircraft Materials
Christian Bareiss, Werner Koelker, Manfred Weigand, Christoph Schiffers, Oliver Lemmer (CemeCon AG, Germany)

Since several years CFRPs are getting more and more important as construction material in the aircraft industry. Their unique combination of light weight and high performance predestine these materials for airplanes of the newest generation and open up new perspectives in various other applications. One of the dominating problems in all these applications is the machining of the extreme abrasive CFRP materials, where diamond coatings demonstrated already their suitability for an economic and reliable production process. For mastering the future machining of the ongoing material improvement, the CemeCon AG developed new multilayer diamond coatings on cemented carbide tools, which combine the excellent performance and fracture toughness of micro-crystalline diamond films and the smooth component part surface, achieved by nano-crystalline, smooth diamond films. On the one hand these multilayer diamond films already proofed their excellent performance in the machining of CFRPs and are commonly used in the run production process. On the other hand they are under continuous further development for future challenges in working with CFRPs. Various results of the multilayer diamond films in the development and in the run production will be presented and compared to other coatings and uncoated tools.

BP-32 Characterization of NiAl / TiAlSiN Thin Films Deposited by Unbalanced Magnetron Sputtering for Glass Modeling Dies Application
Da-Yung Wang, Wei-Chih Chen, Tsung-An Li (Mingdao University, Taiwan)
On the advent of the high demand for high quality and high productivity of non-spherical glass lenses in cell phone, compact camera and car electronics industries, glass modeling becomes the fabrication technique of choice for producing high precision glass lenses at low cost. In this study, the NiAl surface releasing films co-deposited on top of a supportive TiAlSiN thin film was examined as a protection mechanism for glass modeling dies. NiAl /TiAlSiN nano-layered thin films were deposited from Ni, Al and Ti80Si20 compound alloy targets by using pulsed magnetron sputtering technique. The results indicated that the nano-layered NiAl /TiAlSiN films showed higher hardness (28-32 Gpa), higher residual stress (-5GPa), lower surface roughness(Ra<10nm) and better adhesion strength than the conventional mono-layered coatings. The films were characterized by using scanning electron microscopy (SEM), X-ray diffractomery (XRD), X-ray photoelectron spectroscopy (XPS), Nano-indentation, Atomic Force Microscope (AFM) and thermal gravimetric analysis (TGA)/differential scanning calorimetry (DSC) and contact angle measurement.
BP-33 Evaluation of Ca Doped Ce0.8 Gd0.2O1.9 Electrolyte by Various Deposition Method
Seon Ho Yang, Kyung Hwan Kim, Hyung Wook Choi (Kyungwon University, Korea)
SOFCs (Solid oxide fuel cells) based on doped ceria electrolytes offer operating low temperatures. Recently much attention was aimed at successful powder preparation with high sinter activity and conductivity. The properties of ceria electrolyte are very sensitive to impurities introduced during powder and electrolyte fabrication. So, electrolyte powder made of 2% Ca dope Ce0.8 Gd0.2O1.9 (GDC) by glycine-nitrate process and supported by Ni-GDC cermet anode pellets. GDC electrolyte was vapor deposited by screen printing method, RF-magnetic sputtering and E-beam evaporating on the Ni-GDC cermet anode pellets surface. The formation of single-phase monoclinic structure was confirmed by X-ray diffraction (XRD) for the doped 2% Ca Ce0.8 Gd0.2O1.9 (GDC) electrolyte and Ni-GDC anode. The crystal structure and morphology were measured by scanning electron microscopy (SEM) for the sintered samples were performed. The as complex impedance were measured in the temperature of ~60°C (Computer Impedance Grain-Phase Analyzer).
BP-34 Large Scale Deposition of TiC/a-C Nanocomposite Coatings by Magnetron Sputtering using Novel Ceramic Compound Targets
Michael Stueber, Sven Ulrich, Harald Leiste (Karlsruhe Institute of Technology, Germany); Peter Polcik, Michael O`Sullivan (PLANSEE Composite Materials GmbH, Germany)
Carbon-based nanostructured composite thin film materials such as TiC/a-C have attracted large scientific and technical attention with regard of their interesting properties, addressing not only excellent tribological applications (by high wear resistance and simultaneously low friction coefficients) but also electrical, optical and other applications. In the past few years the knowledge on the correlation between synthesis conditions, growth, microstructure and properties of these kind of materials has enormously increased. On the other hand, industrial applications have so far mainly been established for WC/a-C coatings in tool applications. This situation is partially related to the lack of appropriate processes for large scale deposition of such materials over a wide range of coating compositions and on complex shaped component geometry. In this article the large scale deposition of TiC/a-C nanocomposite coatings by means of non-reactive d.c. magnetron sputtering is reported. A novel process route on production level using innovative, newly developed hot-pressed ceramic compound targets of individual TiC:C compositions is presented. The sputtering experiments were carried out with a Hauzer HTC 625 system in the unbalanced magnetron mode. TiC/a-C nanocomposite coatings were deposited under systematic variation of the cathode coil current, substrate temperature, and substrate bias, while the sputtering power density and the gas pressure were kept constant. Coatings of 3-4 microns thickness, well adherent to cemented carbide substrates, are thoroughly characterized by electron microprobe analysis (EPMA), X-Ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Vickers micro hardness measurements, stress measurements and scratch tests. It is clearly shown, that TiC/a-C coatings of identical constitution, microstructure and properties as reported earlier on laboratory scale magnetron sputter deposition from similar hot-pressed ceramic compound targets can be synthesized by this new method. The coatings exhibited Vickers micro hardness values up to 1750 HV0.05, moderate compressive stress up to – 1 GPa and critical load of failures Lc1 of up to 40 N. Applying the new ceramic compound targets very stable, reproducible and easily to control and monitor deposition processes on large scale are available. The results will be discussed both from a materials science perspective and as well with regard to future improving and utilization of the new process and target technology for advanced nanocomposite coating development.
BP-36 Enhanced Efficiency in Dye-Sensitized Solar Cells Based on TiO2 Nanotube/Nanoparticle Composition Powder
Chang Hyo Lee, Kyung Hwan Kim, Hyung Wook Choi (Kyungwon University, Korea)
Enhancing efficiency of dye-sensitized solar cells by combining use of TiO2 nanotube and nanoparticle. TiO2 nanotube is prepared by hydrothermal growth method. TiO2 nanotube and nanoparticle was coated on FTO glass by screen printing method. The dye-sensitized solar cells were fabricated using dye of ruthenium(II)(N719) and electrolyte (I3/I3-). The crystalline structure and morphology were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM). The absorption spectra was measured by UV-vis spectrometer. The conversion efficiency was measured by solar simulator (100mW/cm2). The size and structure of TiO2 nanotubes were adjusted by hydrothermal temperatures. It was found that the conversion efficiency of dye-sensitized solar cells was highly affected by the properties of TiO2 nanotubes. The dye-sensitized solar cell based on TiO2 nanotube/nanoparticle hybrids showed a better photovoltaic performance than the cell purely made of TiO2 nanoparticles.
BP-39 Theoretical Investigation of the Dynamical and Thermodynamic Stability of One Monolayer SiNx Interfaced with TiN
Tobias Marten, Eyvaz Isaev, Björn Alling, Lars Hultman, Igor Abrikosov (Linköping University, Sweden)

The Ti­-Si-N system is attractive for its superhardening, for use as e.g. coatings on cutting tools. The increased hardness upon Si addition to TiN has qualitatively been ascribed to the nanometer dimension of the TiN grains together with the prevention of grain boundary sliding by the so called SiNx tissue phase. However, a quantitative understanding of the hardness enhancement is still not present. The structure of the tissue phase is an important issue and is discussed in the literature.

We study the dynamical and thermodynamic stability of a single monolayer of SiNx embedded isostructurally between B1­TiN (001) and (111) oriented slabs. Phonon calculations show that upon distortion of the Si­N bond the (001) interface is almost stabilized dynamically while the (111) interface is dynamically stable. Moreover, the stoichiometric degree of freedom was relaxed by allowing for Si vacancies in the lattice. Calculations show that the ideal 1:1 SiN stoichiometry in both interfaces are thermodynamically unstable with respect to Si vacancy formation. Thus, the real structure of TiN/SiNx should have another stoichiometry than the ideal B1 interfaces.

BP-41 Magnetron Sputtered ZrN/SiNx Nanocomposite Thin Films: Relationship Between Chemical Composition, Film Morphology and Electrical Properties
David Oezer, Silviu Cosmin Sandu, Rosendo Sanjinés (EPFL, Switzerland)
ZrN/SiNx nanocomposite thin films have been deposited by reactive magnetron co-sputtering using a negative bias voltage of -150V applied to the substrate. X-ray diffraction measurements and TEM investigations suggest a picture of film morphology consisting of ZrN crystallites surrounded by a SiNx layer, where both the size of the ZrN crystallites and the composition of the grain boundaries depend on the deposition parameters. Besides the dependence of the film properties on the substrate temperature and the Si content, the nitrogen flow during the deposition process strongly influences the film structure. Whereas slightly sub-stoichiometric coatings ZrNy/SiNx films (with 0.9 < y < 1) are polycrystalline without preferential orientation, nearly stoichiometric films develop a slight (200) texture in growth direction. Furthermore sub-stoichiometric films show relatively moderate room temperature resistivity values of about 40μΩcm to 100μΩcm depending on the Si concentration, whereas nearly stoichiometric coatings exhibit values that are more than one order of magnitude higher for comparable Si concentrations. The enhancement of the resistivity can be understood by means of higher grain boundary scattering rates due to higher Si incorporation in the grain boundary regions and higher degree of nitridation at the grain boundaries.
BP-42 The Effect of H2S Addition on the Crystal Quality of the Nanocrystalline Diamond Films Grown by the Down-Flow Microwave Plasma-Assisted Chemical Vapor Deposition
Hidenori Gamo (Toppan Printing Co., Ltd., Japan); Mayuko Kikuchi, Kentaro Shimada (Toyo University, Japan); Toshihiro Ando (Northeastern University, Japan); Mikka Gamo (Toyo University, Japan)

Nanocrystalline diamond growth has been extensively studied because its optical, mechanical, and electrical properties are expected to be attractive for both of future applications and scientific interests. In order to grow diamond nanocrystallites, many studies have been performed to introduce defects into diamond structure. For introducing defects, high-energy ions are used to impact the growth surface by applying DC bias voltage to the surface in the plasma. Contrary to this, our growth method in this study focused to realize a damage-free growth process suitable for a high-quality crystal growth.

We used tubular type microwave plasma chemical vapor deposition (MPCVD) reactor for the growth experiments. In our system, the substrate position was apart from the plasma-ball during the growth in the MPCVD quartz reactor. The down stream position is expected to prevent the growth surface from being damaged by ion bombardments and electron irradiation from the plasma. The flow ratio of CH4 to H2 was 10%, and that of H2S to H2 was varied in the range of 0-5.0%. From the analogy of the effect of H2S both on the diamond MPCVD growth and the carbon nanotube MPCVD growth, the added H2S is expected to enhance the sp3 formation and assist the diamond crystal growth.

The film grown with 0.1% H2S in the gas phase was consisted with diamond nanocrystallites approximately 1-2 nm in size from a TEM observation. Negligible amorphous phases and defects were observed in the grain boundaries. The crystal quality was high. The electron diffraction pattern of the film revealed that the nanostructure was diamond.

BP-44 Characterization of Cu-Ag Alloy Thin Films
Jang-Hsing Hsieh, Shummi Hung (Ming Chi University of Technology, Taiwan)

Cu-Ag thin films are known to have better mechanical and electrical properties than Cu or Ag alone. In this study, Cu-Ag thin films with various compositions were prepared using co-sputtering technique followed by rapid thermal annealing at various temperatures. The films’ mechanical and electrical properties were then characterized using XRD, AFM, FESEM, and TEM, as functions of compositions and annealing conditions. The results show that the as-deposited films would transform from one-phase structures to two-phase ones without annealing. The hardness would reach the maximum and 50/50 alloy compositions, and the resistivity would follow Nordheim’s rule prior to the formation of separated phases. After being annealed, the films’ resistivity would follow the mixture rule roughly, mainly due to the formation of Ag-rich and Cu-rich phases. The surface morphology and structure would vary as a function of annealing temperature. From the results, it is found that grain growth varied depending on Ag-Cu compositions.

BP-46 A Comparative Research on Magnetron Sputtering and Arc Evaporation Deposition of Ti-Al-N Coatings
Li Chen, Quan Wang (ZhuZhou Cemented Carbide Cutting Tools Co., LTD, China)
Ti-Al-N coating has been proven to be an effective protective coating for machining applications. Here, the differences of cubic Ti-Al-N coatings with a similar Ti/Al atomic ratio of 1 deposited by magnetron sputtering and cathodic arc evaporation have been studied in detail. Main emphasis was laid on the characterization of the thermal stability and cutting performance. Both coatings during annealing exhibit a structural transformation into stable phases c-TiN and h-AlN via an intermediate step of spiondal decomposition with the precipitation of c-AlN, however, a difference in decomposition process. Compared to sputtered coating inserts, an increase of tool life-time by 42% is obtained by evaporated coating inserts at the higher speed of 200 m/min, whereas the similar cutting life is observed at the speed of 160 m/min. It is attributed to the better stability of evaporated coating due to its later structural transformation at elevated temperature. A post-deposition vacuum annealing of both coated inserts in their corresponding temperature range of spiondal decomposition improves their cutting performance due to an increase in hardness arising from the precipitation of coherent cubic-phase nanometer-size c-AlN domains. Additionally, the sputtered coating behaves worse oxidation resistance due to its more open structure. These behaviors can be understood considering the difference in microstructure and morphology of as-deposited coatings originating from adatom mobility of deposited particles, where arc evaporation technique with higher ion to neutral ratio shows higher adatom mobility.
BP-48 Evaluation of Microstructures and Mechanical Properties of Niobium and Vanadium Carbide Coated H11 Tool Steels
Jyh-Wei Lee (Mingchi University of Technology, Taiwan); Chi-Tsan Lin (Unilift Corp., Taiwan); Meng-Ko Wu, Jen-Ching Huang (Tungnan University, Taiwan)

Niobium and vanadium carbide coatings provide a surface modification layer on steel surface with high hardness and adequate wear resistance. In this study, AISI H11 tool steel was immersed in a molten bath consisting of borax, boric acid, and ferro-niobium and ferro-vanadium to form a carbide coating mixture on the surface.

Surface and cross-sectional morphologies of carbide layers were studied with a scanning electron microscope (SEM) and Energy dispersive spectrometer (EDS). The hardness and elastic modulus of carbide layer was evaluated by nanoindentation. The wear resistance of steels was investigated by pin-on-disk wear tests. Daimler-Benz Rockwell-C adhesion and scratch tests were further conducted to explore the adhesion properties of carbide layers. Carbide layer around 10 um thick with an outer V8C7 and inner (Nb)6C5 phases were observed. The adhesion strength quality of carbide layers was related to HF1 indicating good adhesion properties. It is concluded that the hardness and tribological properties of AISI H11 tool steel were improved effectively by the vanadium and niobium carbide coating.

BP-50 Effect of Nitrogen Content in SiCxNy Thin Films Deposited by Magnetron Co-Sputtering Technique
Rodrigo Pessoa, Henrique Medeiros, Lucia Santos, Homero Maciel, Argemiro da Silva Sobrinho, Marcos Massi (Technological Institute of Aeronautics, Brazil)

The industries of microelectronic devices have been searching for materials capable to operate at aggressive environment. For this, the SiC thin films is a great candidate for this application due some properties as, for example, high operate temperature, good thermal conductivity and high breakdown electric field. However, to improve the electric conductivity is necessary to add nitrogen to the film.

Studies about the effect of nitrogen content in SiCxNy thin films deposited by magnetron co-sputtering technique without substrate heating are presented. This consists of two magnetrons targets arranged in parallel and angled at approximately 20º of the central axis. The magnetron targets are made of 100 mm diameter and 90 W, respectively. The working pressure was fixed at 5 mTorr and the N2/Ar flow ratio was adjusted by varying the N2 flow rate and maintaining the Ar flow rate at 10 sccm. Moreover, SiCxNy films were deposited on p-type (100) silicon substrate that was placed at a substrate-to-target distance of 160 mm. Fourier Transformed Infra Red (FTIR), Composition, chemical bonds and thickness of as-deposited SixCy films were investigated by Rutherford Back Scattering (RBS), Raman spectroscopy and profilometry, respectively. The RBS results indicate that the condition of applied power in magnetron targets allows obtaining approximately stoichiometric SiC films at pure Ar plasma. With the addition of N2 in plasma, the carbon concentration increases for N2 flow > 5 sccm due to the effect of chemical sputtering of carbon target by N2 gas. Raman spectra clearly reveal that the deposited SiCxNy films are amorphous and exhibited C-C bonds corresponding to D and G bands.

BP-52 Enhancement of Thermal Stability on DLC Nanofilm by Using Addition of Silicon Top-Layer
Chen-Kuei Chung, Terry-Yuanfun Chen, Chun-Wen Lai, Ming-Wei Liao (National Cheng Kung University, Taiwan)
The effect of added silicon top-layer on thermal stability of diamond-like carbon (DLC) film annealed at 750°C and 900°C has been investigated. Single carbon film and two-layer Si/C film with thickness of 100 nm and 50/100 nm were used to realize the influence of Si top-layer on the hardness and thermal stability of carbon nanofilm under rapid thermal annealing (RTA). The evolution of surface morphology, microstructure and reaction between C and Si was examined by high resolution field emission scanning electron microscope, Raman and FTIR spectroscopy. The hardness of films was investigated using G-200 Nano Indenter® with Nano CSM-DCM technique. After 750 -900°C annealing, the hardness of single carbon layer decreased seriously at 750°C and then slightly increased at 900 °C due to the formation of SiC at the interface between carbon film and silicon substrate. On the other hand, no significant variation occurred on the hardness of two-layer Si/C film under RTA at 750 -900°C . Although the higher annealing temperature resulted in higher sp2/sp3 bonding ratio as well as more sp2 bonding formation in the carbon layer to soften the structure, the added Si top-layer can sustain the hardness of the composite film because of the SiC film formed on the surface and/or the residual compressive stress of two-layer Si/C films.
BP-53 Formation and Characteristics of ZnNO Thin Film From n-Type to p-Type Conductivity by Thermal Annealing
Yi-Jiun Chen, Tai-Fa Young, Ting-Chang Chan, Tsung-Ming Tsai, Kuan-Chang Chang, Cheng-Hua Li (National Sun Yat-sen University, Taiwan)

In this work, the p-type zinc oxinitride films were fabricated by thermal annealing in air ambience. The Zinc nitride films were deposited onto glass substrate in N2–Ar mixtures by reactive RF magnetron sputtering. The as-grown zinc nitride thin film is a n-type material. It is found that the film treated at 300oC for 3 hours can be changed to a p-type material. The zinc oxinitride films reveal a very low resistance (2.2×10-2 Ω-cm) and high carrier concentration (3.88×1019 cm-3) after the heat treatment. The optical band gap of zinc nitride was determined as a direct band gap varying from 1.1 eV to 1.6 eV according to the temperature of heat treatment. The zinc oxinitride can be prepared with various electrical characteristics and the band gaps modulation by controlling the temperature of heat treatment.

BP-54 Microstructure and Properties of Arc Sprayed Coatings Prepared by Conventional and Nanocomposite Cored Wires
Man Tuiprae, Sittchai Wirojanupatump, Sukanda Jiansirisomboon (ChiangMai University, Thailand)
Ni-base and Fe-base cored wires including WC-Cr-Ni, WC-Cr-Fe, and W-Cr-Fe nano-composite were arc sprayed. The starting cored wires and coatings obtained were characterized by optical microscope (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD), Vicker microhardness tester and dry sand rubber wheel abrasion tester. The results showed that WC-Cr-Fe nanocomposite coating had superior coating microstructure and properties; smoother surface, lower porosity and highest hardness compared to that of conventional cored wire (WC-Cr-Fe and WC-Cr-Ni coating). WC-Cr-Ni coating having high carbide content resulted in high coating hardness; however, this coating exhibited a less dense structure. The WC-Cr-Fe nanocomposite coating exhibited higher abrasive wear resistance than others. Correlation between coating properties and cored wire characeristics will be presented.
BP-56 Study of the Structural and Mechanical Properties of Tungsten Zirconium Nitride Nanostructured Coatings Deposited by by Physical Vapor Deposition
Paritosh Dubey, Ramesh Chandra (Indian Institute of Technology Roorkee, India)
We hereby report the synthesis of Nano-ceramic thin films of Tungsten zirconium nitride on Silicon and 13-4 Cr-Ni steel substrate through DC/RF reactive magnetron sputtering. We have studied the effects of the deposition parameters on the structural and mechanical properties. XRD analysis of the nano-structured samples shows that at low nitrogen pressure the samples are polycrystalline while at high nitrogen pressure it becomes single crystalline. XRD analysis also reveals that there is reduction in grains size with increase in the nitrogen pressure. Microstructural analysis using FE-SEM reveals that the thickness of the film decreases with increase in nitrogen percentage in mixture. AFM study shows, that the roughness of the samples decreases with increase in the percentage of N2 in the ambient gas.

As par survey, we have not found any literature reporting on tungsten zirconium nitride (W-Zr-N) nano-ceramic coating so far. Thus W-Zr-N coating represent a new class of materials which exhibit improved mechanical properties including high hardness and high fracture toughness.

BP-58 Coating of Superalloy with Laser Surface Alloying
Meung Ho Rhee (Korea Automotive Technology Institute, Korea); Won Young Jeung (Korea Institute of Science and Technology, Korea); Joon Won Min, Woo Young Chung (Korea Automotive Technology Institute, Korea)
Superalloys based on Cr-Ni-V-Mo-Fe composition were synthesized by Laser Surface Alloying. The surface treatment temperature of coatings was accurately controlled using continuous wave Nd:YAG laser combined with an infrared sensor in compressed nitrogen atmosphere. For the coatings, multilayer or mixed compounds for the listed Cr-Ni-V-Mo-Fe composition was jointly deposited by RF sputtering and Laser coating at various temperature in nitrogen atmosphere and then synthesized into superalloys through laser surface alloying. Experimental results depending on laser power of depositing and surface alloying, surface temperature of depositing and alloying, and alloying time will be presented. In addition, test data SEM morphology and the evaluated friction resistance of superalloys will be posted. This coating showed a good high temperature resistance behavior and comparatively high were resistance.
BP-60 Heat Treatment of Nanocrystaline TiZrN Film Deposited by Unbalanced Magnetron Sputtering
Qi-You Chen, Jia-Hong Huang, Ge-Ping Yu (National Tsing Hua University, Taiwan); Yu-Wei Lin (Instrument Technology Research Center, Taiwan)
Metal nitride films have been commonly used in industry as protective coatings and metallization layer in industry due to its excellent properties. Moreover, improvements in the properties of thin films were obtained by the deposition of binary, ternary or even higher component systems.

In this study, the nanocrystalline TiZrN thin films were deposited on Si(100) wafer and AISI 304 stainless steel substrate respectively using unbalanced magnetron sputtering. Specimens were later annealed in flowing nitrogen at different temperature ranging from 500°C to 1100°C for two hours. The process of heat treatment affected its microstructure and properties. The texture of the TiZrN films was characterized by X-ray diffraction (XRD); grain sizes were both calculated according to the result of θ/2θ scans. The FWHMs of specimens are decreased with increased temperature. The thickness of the TiZrN thin films was further observed and measured using field-emission gun scanning electron microscope (FE-SEM), measuring about 500 nm. The composition and packing factor of the TiZrN thin films were determined by the Rutherford Backscattering Spectroscopy (RBS). The hardness of the TiZrN films was measured using nanoindenter, which was then observed obviously varying with annealing temperature. The compositional depth profiles were characterized using Auger electron spectroscopy (AES). The electrical resistivity of the TiZrN films was measured using a four-point probe. The corrosion resistance of the TiZrN thin films was obtained from potentiodynamic scanning conducted from -600 to 800 mV in 5%NaCl and 1M H2SO4 + 0.05M KSCN solutions respectively.

BP-61 Morphology and Growth Mechanism of SiC Films Synthesized by Liquid Phase Epitaxy Assisted Chemical Vapor Deposition
Pei-Ting Lee (National Cheng Kung University, Taiwan); Sheng-Chang Wang (Southern Taiwan University, Taiwan); Pramoda Nayak (National Cheng Kung University, Taiwan); James Sung (KINIK Company, Taiwan); Jow-Lay Huang (National Cheng Kung University, Taiwan)

Silicon carbide layers were grown on a Si substrate by liquid phase epitaxy assisted chemical vapor deposition (LPECVD) at a temperature below 1100oC and pressure of 1 atmosphere without SiC seeding. The liquid phase epitaxy assisted chemical vapor deposition was carried out in a tube furnace through cyclic heating process using methane as a carbon source and Sm-Co mixed powder as a solvent for carbon and silicon. The growth of SiC from rare earth Sm-based solvent is an innovative approach, and Co can promote the formation of solvent during the process. X-ray diffraction (XRD), micro-Raman spectroscopy, Electron probe micro-analyzer (EPMA), Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM) were used to characterize the properties of SiC. The growth mechanism of SiC deposited by LPECVD was also discussed in this study. Results indicated that β-SiC was successfully fabricated on (111) Si substrate without SiC seeding by LPECVD. The heterogeneous nucleation of β-SiC was found to be observed initially at the edge of triangle-shaped sites on (111) Si surface, which was formed due to the existence of Co, and then grew and expanded to form β-SiC film.

BP-62 Synthesis of CrN and CrAlN Coatings for High Temperature Wear Applications
HÜSEYİN ALAGÖZ, Mustafa Fatih Genisel (Bilkent University, Turkey); MERT UĞRAŞ (Atılım University, Turkey); Erman Bengu (Bilkent University, Turkey)
Transition metal nitrides as protective coatings have been studied by scientists and engineers, since they were shown to have good wear, erosion and corrosion resistance. In this study, two of the most promising nitride based-coatings, namely CrN and CrAlN, were synthesized by reactive magnetron sputtering technique on Si(100) and steel (100Cr6) substrates using different gas ratios, substrate bias and target power levels. We investigated the change in the phase make-up, hardness, high-temperature wear properties and surface roughness of these coatings. Scanning electron microscopy (SEM) was used to understand the effect of process parameters on surface roughness and microstructure of the films. We utilized atomic force microscopy to quantify the roughness of the films. Also, during SEM investigation, we used energy dispersive spectroscopy (EDS) to obtain the Cr/Al ratios of the films. The hardness values of the films were measured using the nano-indentation technique and, we used a high-temperature tribometer (up to 800°C) to investigate the high-temperature wear-rates of the coatings. X-ray photo-electron spectroscopy (XPS) has been employed to understand the bonding states of Cr and Al to nitrogen and oxygen on the as-deposited surfaces and on wear tracks. Our findings revealed that the surface roughness of the films improved with decreasing the Ar/N2 ratio, while measured hardness values for the films increased. Increasing the Al content of the films caused an improved high-temperature behavior, as well. Furthermore, our investigations at the wear tracks showed presence of higher ratio of Al-O species which we believe to have contributed to the lower wear rates of the CrAlN coatings with higher Al content.
BP-64 Hot Filament CVD Grown Diamond Films at Various Total Mass Flow Rates under Constant Residence Time
Mubarak Ali, Mustafa Urgen (Istanbul Technical University, Turkey)
In the present study, a self-biased Hot-Filament Chemical Vapour Deposition system was used to deposit diamond film over Silicon substrate. A constant residence time (tr = 1010 sec) for precursor’s gases (H2 +CH4) at total mass flow rates of 200, 300 and 400 sccm was selected with two different concentrations of CH4; to compare the quality of deposited diamond. To analyze the morphology, growth rate, crystal orientation and quality of deposited diamond, standard characterization techniques were utilized. Surface morphology and fracture cross-section images of SEM reveal that deposited coatings exhibit similar surface morphology and crystal orientation but improved growth rate at all total mass flow rates. By increasing CH4 concentration at tr = 1010 sec increased the growth rate but deteriorated the quality of deposited diamond. The results obtained indicate that by adjusting ‘tr’ coating deposited at total mass flow rate of 100 sccm represent a similar trend in its properties for forthcoming like wise 200, 300, 400 sccm and so on. Present approach enable us to evaluate the diamond coating properties at higher mass flow rates by keeping constant ‘tr’ without the execution of original line of experiment.
BP-65 Improved Adhesion and Tribological Properties of Hard Graphite-Like Hydrogenated Amorphous Carbon Films Grown by a Remote Plasma on Steel Substrates
Teodor Zaharia (Eindhoven University of Technology, Netherlands); Roland Groenen (N.V. Bekaert S.A., Belgium); Richard van de Sanden (Eindhoven University of Technology, Netherlands)

Recently we reported on a novel form of hard graphite-like hydrogenated amorphous carbon deposited by an expanding thermal remote plasma in an Ar – C2H2 environment [1, 2]. The graphite-like films deposited on Si and steel substrates are dense (~2.0 g/cm3) and very smooth, with RMS roughness below 4 nm for film thicknesses above 1µm, which makes them ideal candidates for tribological applications.

However, dense a-C:H material commonly leads to high compressive stress, which in turn causes poor adhesion on metallic substrates. The influence of a Ti metallic interlayer in between M2 steel substrates and the hard graphite-like films is investigated by monitoring adhesion with the Rockwell C test and the scratch test as a function of carbon film thickness, interlayer thickness and deposition temperature. It is shown that a sputtered Ti interlayer deposited at substrate temperatures of 200 – 250°C and with an adjusted thickness dependant on the carbon film thickness improves the adhesion drastically. This can be explained by a more densely packed film structure at higher temperatures and by a roughening effect of the top Ti surface with increasing thickness, due to grain coarsening. The wear rates of the a-C:H/Ti/M2 steel stack against a 100Cr6 ball counterpart in a ball-on-disk test were found to be very competitive, in the order of 2.5 × 10-17 m3/Nm.

[1] S.V. Singh et al., Appl. Phys. Lett. 92 (2008) 221502.

[2] S.V. Singh et al., J. Appl. Phys. 107 (2010) 013305.

BP-66 Structure Characterization and Antibacteria Behavior of TaN-Ag, TaN-Cu and TaN(Ag,Cu) Nanocomposite Thin Films
Yin-Jei Lin, Jang-Hsing Hsieh, Shummi Hung (Ming Chi University of Technology, Taiwan); Chuan Li (National Central University, Taiwan)

TaN-(soft metal) nanocomposite thin films have been shown to have good mechanical properties. This study aims at comparing the antimicrobial behaviors of TaN–Cu, TaN-Ag, and TaN-(Ag,Cu) nanocomposite films. These films were deposited by reactive co-sputtering on Si. They were then annealed using RTA (Rapid Thermal Annealing) at 400°C to induce the nucleation and growth of metal particles in TaN matrix and on film surface. After being characterized using XRD, FESEM, and TEM, the samples were tested for their anti-bacterial behaviors against Gram-negative and Gram-positive bacteria. It is found that TaN-Ag is more effective against E. Coli (Gram-negative), while Cu ion or TaN-Cu is more effective against Staphylococcus aureus (Gram-positive). For TaN-(Ag,Cu), a synergistic effect is observed. This film is effective against both types of bacteria. The wider application is expected.

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