Syposium F Poster Session

Thursday, May 2, 2013 5:00 PM in Room Grand Hall

FP1 Mechanical Properties of Patterned Oxide Structures on Compliant Substrates for Flexible Optoelectronics
Konstantinos Sierros (West Virginia University); Theodros Bejitual, Nicholas Morris, Darran Cairns (West Virginia University, US)

There is currently great interest to design and fabricate novel flexible devices for solar cell, solid-state lighting, biomedical and energy harvesting applications. Such devices require the use of electrode components. Desired electrodes must exhibit structural integrity, low electrical resistivity and, in most cases, high optical transparency in the visible range.

Despite growing efforts to replace them, transparent conducting oxides layers deposited on polymer compliant substrates are still enjoying a dominant role as the electrode material. This is because of their excellent electrical and optical properties. However, their performance when they are subjected to externally applied mechanical stresses is limited. Such performance has been extensively investigated for the case of continuous brittle oxide films on polymer substrates. However, there is relatively little work reported to date on the mechanical behavior of patterned conducting layers on compliant substrates. Patterned brittle structures may be able to accommodate higher mechanical strains because of their controlled shape, size and edge definition.

In this study we report on the mechanical behavior of various patterned indium tin oxide (ITO) shapes on polyethylene terephthalate. Micron-sized shapes include lines, circles, squares and zigzag-based structures. Uniaxial tensile and buckling experiments are performed in-situ using an optical microscope in order to monitor critical strains and potential failure mechanisms. In addition, in-situ electrical resistance measurements are conducted during mechanical deformation. We also report on the effect of ITO etching time and edge definition. Furthermore, ex-situ characterization using scanning electron and atomic force microscopies is conducted. Finally, experimental results are compared with modeling studies.

We believe that this work is providing an improved understanding that will aid towards designing patterned flexible device platforms with enhanced structural integrity.

FP2 Influence of H-radical Irradiation on the Properties of a Ge/SiC Nanodot/SiC Stacked Structure
Kai Satou, Yutaka Anezaki (Nagaoka University of Technology, Japan); Maki Suemitsu (Tohoku University, Japan); Hideki Nakazawa (Hirosaki University, Japan); Yuzuru Narita (Yamagata University, Japan); Ariyuki Kato, Takahiro Kato (Nagaoka University of Technology, Japan); Kanji Yasui (Nagaoka Univeversity of Technology, Japan)

Semiconductor quantum dots can confine carriers such as electrons and holes in three-dimensions and exhibit unique electronic and optical properties. For highly efficient IR light-emitting devices using Ge nanodots, a high density of small Ge nanodots, less than 10 nm in diameter, is required. It has been reported that a density of 2×1011 cm2 nanodots was achieved by the pregrowth of submonolayer carbon.[1] In this case, carbon atoms were incorporated into a Si(001) substrate and surface strain was induced, leading to the formation of a Si(001) c(4×4) reconstruction structure at the surface layer, which changed the Ge growth from the Stranski–Krastanov (SK) mode to the Volmer-Weber (VW) mode and resulted in formation of a high density of nanodots. Strong repulsive interaction can operate between Ge and C; therefore, Ge atoms deposited on the SiC layer do not interdiffuse. The c(4×4) surface was expected to function as a template substrate for the formation of a high density of Ge nanodots. We have previously reported that the c(4×4) structure is formed by the reaction of monomethylgermane (MMGe) on the Si(001) 2×1 surface. The Ge nanodots embedded in the SiC structure are expected to strongly confine carriers, due to the difference in the bandgap between Ge and SiC. Ge nanodot formation using MMGe resulted in the formation of SiC and Ge nanodots after the appearance of the c(4×4) reconstructed surface. Using a pulse-controlled nucleation method, the formation of a high density (1.3×1011 cm-2) of nanodots (6 nm) with a small standard deviation (1 nm) was achieved. We have previously reported reflection high-energy electron diffraction (RHEED) and scanning tunneling microscopy (STM) results for the surface structure of Ge and SiC nanodots fabricated using MMGe.[2] Photoluminescence (PL) spectra of Ge nanodots capped with a SiC layer were also measured at low temperatures.

In this study, the influence of H-radical irradiation on the photoluminescence properties of Ge/SiC nanodots was investigated. The apparatus configuration and conditions for the growth of Ge/SiC nanodots were the same as those reported previously, except for the addition of a tungsten wire. The tungsten wire (0.2 mm diameter) was heated at 2073 K to generate H-radicals after the growth of Ge/SiC dots and after deposition of the SiC capping layer. The substrate temperature was maintained at 473K-673 K according to the temperature for H-desorption from the Ge-H surface.[3]

Reference s

[1] M. Stoffel et al., Thin Solid Films 380, 32 (2000).

[2] Y. Anezaki et al., Abstracts of the 39th ICMCTF, San Diego (2012) p. 120.

[3] J. Y. Lee et al., J. Chem. Phys. 118, 1929 (2003).

FP3 Shape Controllability and Photoluminescence Properties of ZnO Nanorods Grown by Chemical Bath Deposition
Tomoaki Terasako, Toshihiro Murakami (Graduate School of Science and Engineering, Ehime University, Japan); Masakazu Yagi (Kagawa National College of Technology, Japan); Sho Shirakata (Graduate School of Science and Engineering, Ehime University, Japan)
Much attention has been given to the fabrication of ZnO nanostructures because of their potential applications in opt-electric devices. Chemical bath deposition (CBD) method permits low growth temperatures suited for the fabrication of the nanostructures on the flexible substrates, such as metal foils and polymers. In this paper, shape-controllability and photoluminescence properties of ZnO nanorods (NRs) grown by the CBD method using the aqueous solution of zinc chloride (ZnCl2) and the mixed aqueous solution of zinc acetate dehydrate (ZnAc) and hexamethylenetetramine (HMT) will be discussed.

Glass slides, Au films and (Mg,Zn)O/glass films prepared by chemical spray pyrolysis were used as substrates. The concentration of ZnCl2 in the aqueous solution was changed in the range from 0.02 to 0.24 M. The pH value of the ZnCl2 solution was adjusted to 10.0 by adding ammonia water. The concentration of ZnAc was changed in the range from 0.01 to 0.02 M and the molar ratio of HMT to ZnAc was kept at 1:1. The temperature of the water bath was kept at 90°C during the deposition process. Growth time (tg) was varied in the range from 15 to 240 min.

X-ray diffraction (XRD) measurements and scanning electron microscope (SEM) observations revealed the successful growth of vertically aligned ZnO NRs with preferred c-axis orientation on the Au and (Mg,Zn)O seed layers. When tg increased from 15 to 180 min, the average diameter of the NRs grown using the ZnCl2 solution of 0.17 M increased from 150 to 1000 nm together with the change in shape from cones to hexagonal prisms. For the ZnAc solution of 0.03 M, the diameter increased from 100-400 nm for tg=60 min to 550-1000 nm for 240 min.

PL spectra from the as-grown NRs were composed of an orange (OR) emission and a near-band-edge (NBE) emission. The appearance of the OR emission suggests that the NRs have the high density of interstitial oxygen atom in their surface regions. For the NRs grown using the ZnCl2 solution, the relative intensity of the NBE emission to the OR emission was independent of tg. For the NRs grown using the ZnAc solution, however, the relative intensity of the NBE emission to the OR emission became larger with increasing tg, suggesting the improvement of the crystalline quality. PL excitation (PLE) measurements for the NRs grown using the ZnAc solution revealed that the OR emission was effectively excited at the photon energy corresponding to the A free-exciton energy. However, PLE spectra for the OR emission from the NRs grown using the ZnCl2 solution showed that the secondary phase Zn(OH)2 formed at the surface regions of the NRs contributed to the excitation process for the OR emission.

FP4 Optical Properties of La2O3 Thin Films Deposited by RF Magnetron Sputtering
SilviaBeatriz Brachetti-Sibaja, MiguelAntonio Domínguez-Crespo, AideMinerva Torres-Huerta (Instituto Politécnico Nacional, Mexico); Sandra Rodil (Universidad Nacional Autónoma de México, Mexico)
In spite of the high potential applications of lanthanum oxide thin films, only few studies have investigated the correlation between deposition conditions and optical properties. La2O3 films have been deposited by different physical thin film growth methods such as electron-beam evaporation, pulsed-laser evaporation and vacuum evaporation, but not by sputtering.

In the present work, lanthanum oxide films were deposited by radiofrequency magnetron sputtering from a La2O3 target in an Argon atmosphere (20 mTorr). The films were deposited onto Si(100) and glass substrates. Two different RF-powers were tested (60 and 90 watts) and for each power, the deposition time was changed from 25, 40 and 60 minutes, as well as the substrate temperature (ambient and 200°C). The film thickness was measured by profilometry obtaining variations between 102 nm for the 60 W with 25 minutes and ambient temperature and 1097 nm for 90 W with 60 minutes and 200 ºC of temperature. The structure, morphology and chemical composition was studied by X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), and Scanning Electron Microscopy (SEM), respectively. The optical properties were estimated by modeling the ellipsometric spectra (1.5 to 5 eV) using Tauc-Lorentz dispersion models. The results from the ellipsometric model were compared with the transmission spectra obtained in the UV-VIS range for the films deposited on glass.

Acknowledgements for authors to CONACYT CB-2009, SIP 2012-1303 and PAPIIT IN103910.

FP5 ZnO Nanostructures as Efficient Antireflection Layers in High Efficiency Non-selenized Cu(In,Ga)Se2 Solar Cells
Bao-Tang Jheng (National Tsing Hua University, Taiwan, Republic of China); Po-Tsung Liu (National Chiao Tung University, Taiwan, Republic of China); Ying-Pin Chang (Nan Kai University of Technology Nantou, Taiwan); Meng-Chyi Wu (National Tsing Hua University, Taiwan, Republic of China)
Non-selenized Cu(In,Ga)Se2 (CIGS) thin-film solar cells with a zinc oxide (ZnO) nanorod/ Al and Y codoped ZnO(AZOY)/ ZnS/ CIGS/ Mo/ SLG structure have been fabricated using an aqueous synthesis solution method-ZnO nanorod arrays layer and high quality CIGS absorber layers grown using sputtering system.The use of ZnO nanorod arrays antireflection (AR) coating, which is a higher light-trapping probability than dielectric MgF2, improved the reflectance of fabricated cells at UV–visible wavelengths, leading to an increase in the short-circuit current. In the work, we successfully applied ZnO nanorod arrays in the production of non-selenization CIGS thin-film solar cell devices, to achieve the low reflection incident light and to better the solar cell device conversion efficiency to around 10%.
FP7 Phase Stability of Bi2O3 Thin Films prepared by Reactive Magnetron Sputtering
Osmary Depablos-Rivera, Phaedra Silva-Bermudez, Sandra Rodil (Universidad Nacional Autónoma de México - Instituto de Investigaciones en Materiales, Mexico); Enrique Camps (Instituto Nacional de Investigaciones Nucleares de Mexico)

Bismuth oxide thin films were deposited by reactive magnetron sputtering from a Bi2O3 target (99.95 at%) using RF and an Ar/O2 atmosphere (80/20). The films were deposited on silicon and glass substrates at 120 W and 150oC. Under these conditions, the films were stoichiometric and showed the cubic delta phase, which is usually the stable phase of bismuth oxide at high temperatures (725-850oC). However, as a thin film, it has been shown that the delta-phase can be obtained even at room temperature conditions. The delta Bi2O3 is the high ionic conductivity, which is searched for solid oxide fuel cell applications, as the solid electrolyte. The objective of this work is to study the structural stability of the delta-phase films as a function of the both the storage-time and thermal treatments in air. The films were storage under environmental conditions (25oC, 760 Torr). The film structure was obtained by X-ray diffraction and Raman spectroscopy, which is a very useful technique to identify the presence of the disorder inherent to the delta phase. Similarly, the optical properties have been measured by both transmission and spectroscopic ellipsometry. The films kept at ambient conditions have been analyzed periodically, after a year no changes in the structure have been observed, which is a good indication. Annealing experiments were done in air from 120oC to 500oC, in order to identify the temperature at which phase transition occurs. The results indicated that the film structure is stable up 210oC where the d-phase remained unchanged. Higher temperatures lead to phase transitions into the beta phase up to 360oC, above this temperature, some regions started to show the alpha-phase. The optical transmission increases with the annealing temperature.

Acknowledgement: The research leading to these results has received funding from the European Community Seven Framework Program (FP7-NMP-2010-EU-MEXICO) and CONACYT under grant agreements nº 263878 and 125141, respectively.

FP8 Photocatalytic Activity of Bismuth Oxide Thin Films
JuanC Medina, Sandra Rodil, Monserrat Bizarro, Phaedra Silva-Bermudez (Universidad Nacional Autónoma de México - Instituto de Investigaciones en Materiales, Mexico)

Bismuth oxide (Bi2O3) thin films were deposited by Magnetron Sputtering technique under different deposition conditions; substrate temperature and RF power in order to obtain films having different crystalline phases. X-ray diffraction, profilometry, scanning electron microscopy, and optical transmission were used to characterize the films. The results indicated that it was possible to obtain oxide films in the alpha, beta and delta phase, depending on the deposition conditions. The photocatalytic activity for each one of the Bi2O3 phases was evaluated testing the degradation of methyl orange dye (C14H4N3SO3Na) under different light energies (ultraviolet, white and solar light). The photocatalytic activity was measured as a function of the irradiation time, light-energy, concentration and pH of the solution. The colorant degradation and the kinetic of the reaction were estimated using the variation of the corresponding absorption band situated at 508 nm (acid media) and 461 nm (neutral and basic media). For the UV light (380 nm and power of 9 W), the results pointed out that the photocatalytic effect was only activated under acidic conditions, for the other pHs, the activity was negligible. Moreover, it was also found that the delta-phase films presented larger photocatalytic efficiency reaching almost 100% of degradation of the dye solution in only 60 minutes, which was an remarkable result considering the photocatalytic performance of other oxides in similar conditions. The rate of reaction of the delta-phase samples was almost twice than that obtained for the other phases. The rate of reaction was used to compare the efficiency of the catalytic reactions and to correlate it with other physicochemical properties, such as the band gap. These results suggest that the Bi2O3 films are a rather new and promising photocatalytic material for water treatment application.

Acknowledgement: The research leading to these results has received funding from the European Community Seven Framework Programme (FP7-NMP-2010-EU-MEXICO) and CONACYT under grant agreements nº 263878 and 125141, respectively.

FP9 Synthesis and Characterization of Copper Nanoparticles by Solution Plasma Processing
SungMin Kim, SungChul Kim, SangHoon Jin (Korea Aerospace University, Republic of Korea); GoocJin Yoon, SangWoo Nam, JungWan Kim (University of InCheon, Republic of Korea); SangYul Lee (Korea Aerospace University, Republic of Korea)
Copper nanoparticles were synthesized with various discharge durations in the presence of amide and acid capping agent using solution plasma processing (SPP), and the effects of the discharge duration between 60 and 600 s on the size and shape of the copper nanoparticles were investigated using UV–Vis NIR spectrophotometry, X-ray diffactometer (XRD), and transmission electron microscopy (TEM). The results showed that discharge duration had a strong effect on the formation of copper nanoparticles. Using high voltage power supply, copper nanoparticles was rapidly formed after discharge at 60 sec and the size and shape of copper nanoparticles were dependent on discharge time, indicating a strong effect of capping agent under various discharge media characteristics (pH and temperature). With long discharge time, copper nanoparticle size tended to decrease with the formation of various particle morphologies, spherical, cubic, hexagonal, triangular, and rod–like shapes. The decrease in size as a function of discharge time could be explained by the dissolution of copper nanoparticles in lower pH solution at higher temperature. After discharge at 300 sec, the role of capping agent evidently showed the shape control and oxidation protection of the synthesized copper nanoparticles. The desirable size and shape of copper nanoparticles without the undesirable oxidation could be controlled by adjusting discharge time of solution plasma. Detailed experimental results will be presented.
FP12 Effect of Substrate Bias and Hydrogen Addition on the Residual Stress of Hexagonal Boron Nitride Film Prepared by Sputtering of B4C Target with Ar/N2 Reactive Gas
Jong-Keuk Park, Jung-Hoon Lee, Wook-Seong Lee, Young-Joon Baik (Korea Institute of Science and Technology, Republic of Korea)

cBN (cubic boron nitride) shows outstanding mechanical properties such as hardness and wear resistance. Despite of the excellent properties, high stress developed during the deposition of cBN film deteriorates adhesive strength of the film and restricts the application for coating material. Recently, addition of hydrogen [1,2] was reported to be useful technique to reduce the residual stress of cBN film prepared by sputtering of B4C as well as hBN targets. Ar incorporation between (0002) planes of hBN (hexagonal boron nitride) was suggested to be the main origin for the residual stress observed in boron nitride film, which could be suppressed by the hydrogen addition through the formation of sp3 bonding at the growing hBN (0002) plane edge. In this study, we have investigated systematically the effect of substrate bias and hydrogen addition on the residual stress of hBN film prepared by magnetron sputtering of B4C target. The deposition was performed on Si (100) substrate under the chamber pressure of 0.27 Pa with substrate bias from -200V to -300V. After the deposition of B4C layer, hBN film was deposited with a step-wise increase of nitrogen flow rate from 0 sccm to 4.5 sccm in Ar/N2 mixed gas with a constant Ar flow rate of 25 sccm. Hydrogen (5 sccm) was added to a gas mixture of argon and nitrogen flowing 25 sccm and 5 sccm, respectively to investigate hydrogen effect on the residual stress. The compressive residual stress of hBN film was observed to be decreased from 5.0 GPa to 2.8 GPa, with increasing substrate bias voltage from -200V to -300V. The hydrogen addition reduced the compressive residual stress value of hBN film further. The decreasing behavior of the compressive residual stress observed in the hBN film with increasing substrate bias is difficult to be explained only by the effect of lattice defect and distortion induced by ion bombardment. In this presentation, the stress variation with substrate bias and hydrogen addition was discussed in terms of the relation between the penetration probabilities of argon ions into the film.

[1] H.-S. Kim, J.-K. Park, W.-S. Lee and Y.-J. Baik, Thin Solid Films 519 (2011) 7871–7874.

[2] J.-K. Park, Ji-Sun Ko, W.-S. Lee and Y.-J. Baik, B1-2-12, 39th ICMCTF (2012).

This research was supported by a grant from the Fundamental R&D Program for Core Technology of Materials funded by the Ministry of Knowledge Economy, Republic of Korea

FP13 In-situ Biaxial Loading During X-Ray Diffraction and Digital Image Correlation Measurements: Application to Metallic Thin Films Supported by Polyimide Substrates
PierreOlivier Renault, Eric Le Bourhis (University of Poitiers, France); Damien Faurie (University of Paris 13, France); Guillaume Geandier (University of Lorraine, France); Philippe Goudeau (University of Poitiers, France); Dominique Thiaudière (Synchrotron SOLEIL, France)

The objective of the present work is to study the co-deformation of composite exhibiting strong mechanical contrast components: nanostructured metallic thin film deposited onto polymeric substrate. The mechanical characterization of such composite structures and the relationship with the microstructure still required for further understanding both for fundamental and technological applications. In order to mimic the stress field of thin films in actual applications, we used a biaxial tensile device dedicated to the DiffAbs beamline at the French synchrotron SOLEIL. The machine allows for controlling equi- or non-equi-biaxial loading onto thin films supported onto compliant substrates, e.g. polyimide substrates. The applied strains are measured in situ both by X-ray diffraction (XRD) and by digital image correlation (DIC). Those two methods are non-destructive: XRD strain is related to the shift of Bragg peaks and DIC strain is obtained from photography of the surface or the backside of the sample. The inherent phase selectivity of XRD technique is a useful tool to get a deeper understanding of the mechanical behaviour of a composite, e.g. the load transfer between the different crystallographic phases and between different orientation grains. The in-situ mechanical testings have been performed onto metallic thin films (produced by Physical Vapor Deposition technique) deposited at the center of a cruciform-shaped polyimide substrate (Kapton ®). In order to verify the accuracy and the feasibility of the combination of the two techniques, the first in situ coupling correlation-diffraction techniques have been performed on W based thin films. Indeed the mechanical modeling using homogenization methods is quite specific for thin films; it has to take into account both the crystallographic texture and morphology of the metallic films. The grain interaction model is very simple in the case a perfect local elastic isotropy such as W. W based thin films allows for directly comparing lattice strains (measured at the microscopic grain scale by X-ray diffraction) to macrostrains (measured at the macroscopic scale by DIC).

FP14 Antimicrobial Brass Coatings Prepared on Poly(ethylene terephthalate) Textile by High Power Impulse Magnetron Sputtering
Ying-Hung Chen, Guo-Wei Chen, Ju-Liang He (Feng Chia University, Taiwan, Republic of China)

Silver coating, particularly prepared by magnetron sputter deposition, has been proven to be antimicrobial and on the way towards commercialization for application in textile industry. However, the expensive raw material and unsatisfactory film adhesion has limited its usage. Copper, on the other hand provides good enough antimicrobial efficacy of all the metals, is considered for silver substitution, but unfortunately suffers poor corrosion resistance in form of thin film coating. Brass, known to be good corrosion resistance, is a good candidate material for antimicrobial coating. The purpose of this study is to obtain an antimicrobial coating starting with brass alloy as target material to grow onto poly(ethylene terephthalate) (PET) textiles by high power impulse magnetron sputtering (HIPIMS), which is known to provide high plasma density, so as to produce strongly adhered film and high quality films at a reduced deposition temperature.

The results show that under a peak target power density of 0.6 kW/cm2, the obtained brass film exhibited layer-by-layer growth mode in the initial stage, followed by island growth mode and reached a film thickness of 238 nm for 10 min deposition. Film composition retained their Cu/Zn ratio (1.86) close to that of brass target, and the phase structure of the film was found to be mainly α-brass. From the results of color fastness to rubbing tests, the film ultimately reached graded 5 and graded 4-5 at dry and wet rubbing, respectively, indicating strong adhesion of the obtained film. Antimicrobial efficacy test show that simply 1 min deposition time can achieve good bactericidal (> 0) and bacteriostatic (> 2.0) efficacy according to the JIS Standard.

Keywords: antimicrobial, poly(ethylene terephthalate), textile, high power impulse

FP16 Influences of Various Feedstocks on Characteristics of the Plasma Sprayed NiO/YSZ Anode in Solid Oxide Fuel Cell
Yung-Chin Yang, Han-Cheng Tseng, Chen-Te Cheng (National Taipei University of Technology, Taiwan, Republic of China)
In the present study, porous electrode coating of NiO/YSZ on the stainless steel was made by the plasma-spraying. By introducing the Na2CO3 as the pore former into the composite feedstock powder (NiO/8YSZ/Na2CO3), the porous structure of SOFC anode was obtained. Two kinds of feedstocks from various synthesis processes were employed. The powder made by the spraying-dry method reveal more porous than that from the hand made granulated method. The porosity of porous anode after Na2CO3 dissolved and reduction in 5% hydrogen could be varied from 30 to 40%. The results suggest that the method exhibits the potential to manufacture the porous ceramic/metal anode of SOFC to achieve the large triple phase boundary. Moreover, the plasma spraying technique for SOFC fabrication could avoid the thermal failure between the components of SOFC which made from the traditional sintering method at high temperature.
FP17 Effect of Mo Content on Structure and Corrosion Resistance of Arc Ion Plated Ti-Mo-N Films on 316L Stainless Steel as Bipolar Plates for Polymer Exchange Membrane Fuel Cells
Min Zhang (Liaoning Normal University, China); Kim Kwang Ho (Pusan National University, Republic of Korea); Shao Zhigang (Dalian Institute of Chemical Physics); Pan Yunli, Hu Xiaogang, Huang Ye (Liaoning Normal University, China)
Bipolar plates are one of the most important components in PEMFC stack and have multiple functions, such as separators and current collectors, distributing reactions uniformly, mechanically supporting the cell stack and managing the heat and water of the cells. Stainless steel is ideal candidate for bipolar plates owing to good thermal and electrical conductivity, good mechanical properties etc. However, stainless steel plate still cannot resist the corrosion of working condition.
In this work, solid solution Ti-Mo-N films were fabricated on 316L stainless steel (SS316L) as a surface modification layer to enhance the corrosion resistance and conductivity. A hybrid system, which combines arc ion plating and magnet sputtering, was employed to prepare the Ti-Mo-N films. Mo content in the Ti-Mo-N films is controlled by adjusting the sputtering power of Mo target. The effect of Mo content on structure and corrosion resistance of the Ti-Mo-N films was investigated by means of XRD, EPMA, and anode polarization tests.
Mo content in the Ti-Mo-N films increases linearly from 0 to 48 at% when the sputtering current increases from 0 to 1.0 A. XRD results show the films are solid solution, crystallize in TiN phase, and the preferred orientation changes from (111) to (200) plane as Mo content increases. The corrosion resistance of the coated SS316L bipolar plates becomes worse as Mo content increases, and the TiN (Mo content is 0) coated plates show the best corrosion resistance. Compared to the bare SS316L bipolar plates, the coated plates show improved corrosion resistance and lower ICR, i.e. for the TiN coated plates, corrosion and passivation current density reduces by one and four orders of magnitude, respectively; the ICR decreases by two orders of magnitude. The improved corrosion resistance and conductivity of the TiN coated bipolar plates is attributed from the integrate lattice and a (111) preferred orientation in the TiN film, which is the close-packed plane in body-centred cubic TiN phase.

FP18 The Smoke Density Evaluation of Acrylic Emulsion and Intumescent
Zhishi Li, Huajin Wang, Wei Zhao, Wei Lu, Jun Zhao (Marine Chemical Research Institute, State Key Lab of Marine Coatings, China)
The emulsion based coatings have induced pollutions to the environment, eliminate the fire dangerous, and saving resources. More and more investigations are focused on the emulsion based coatings. Herein, we fabricated a novel kind of intumescent fire resist coatings with acrylic emulsion, and discuss the smoke density feathers of both acrylic emulsion and intumescent. Initially, the static smoke density of both acrylic emulsion and intumescent is measured, and the capability influence of acrylic emulsion to intumescent is discussed. Meanwhile, the thermal decomposition kinetics of both acrylic emulsion and intumescent are investigated. Results show that acrylic emulsion has a quite higher smoke density comparing to intumescent during burning process. The thermogravimetric (TG) and derivative thermogravimetric (DTG) curves of both acrylic emulsion and intumescent are obtained. Through multiple peaks fitting of intumescent DTG curve, every step of thermal decomposition could be separated, and be identified to each ingredient of intumescent. Combining with the smoke density data, the smoke contribution of acrylic during the intumescent burning process could be estimated. Approximately, acrylic emulsion is decomposed 13.1% for whole, that’s the 3.51% of intumescent. These results can be deduced that acrylic contributes 51.57% in smoke density during the intumescent burning process. The intumescent exhibits lower smoke density while comparing to acrylic emulsion. The reason of such phenomenon could be speculate that during the burning process, the fire retardant system may restrain the decomposition of intumescent, cause the total smoke density reduce.

Keywords emulsion, smoke density, acrylic, intumescent

FP19 Effects of Duty Cycle and Pulse Frequency on the Fabrication of AlCrN Thin Films Deposited by High Power Impulse Magnetron Sputtering
Yu-Chiao Hsiao (National Taipei University of Technology, Taiwan, Republic of China); Jyh-Wei Lee (Ming Chi University of Technology, Taiwan, Republic of China); Yung-Chin Yang (National Taipei University of Technology, Taiwan, Republic of China)

High power impulse magnetron sputtering (HIPIMS) is a novel coating technology, which is characterized for its high peak power density to achieve unique thin film properties, such as high hardness, good adhesion and tribological performance. The aim of this work was to systematically study the microstructure evaluation and mechanical properties of AlCrN coatings as a function of duty cycle and pulse frequency evolutions. The experimental results showed that the peak power density increased linearly as the duty cycle decreaseing from 5% to 1.5%. A maximum peak power density of 2.06kW/cm2 was achieved at the duty cycle of 1.5 %. The AlCrN coatings that exhibited a dense microstructure and excellent mechanical properties was fabricated by using the HIPIMS technology under optimal duty cycle and pulse frequency in this work.

FP20 Enhancing the Thermal Stability and Oxidation Resistance of the Cr Zr N Films by Adding Oxygen
DongJun Kim, JoungHyun La, SungMin Kim, YehSun Hong, SangYul Lee (Korea Aerospace University, Republic of Korea)
CrZrON coatings were produced by reactive magentron sputtering at different N2/O2 flow ratios on the Si wafer substrate and H13 tool steel substrates. The structure, and mechanical properties of the coatings depend strongly on their oxygen content. T he coatings crystallize in the rhombohedral Cr2O3 structure and CrZrN cubikc stricture . The morphology of the samples, as studied by scanning electron microscopy (SEM), is columnar. The hardness of the CrZrN coatings (31.6±0.8 GPa) decreases with increasing oxyzen content in the coatings and the hardness decreased down to 15.5±0.8 Gpa in CrZrO coatings. Higher oxygen contents lower the hardness of the coatings. X-ray powder diffraction (XRD) studies were performed in air and t he increase of the oxygen content leads to an enhancement of the (002) preferred orientation and CrZrO coatings became amorphous structure. The Cr Zr ON coatings showed an improved thermal stability against oxidation with increasing oxygen contents in the coatings, which could be attributed to the protective oxide layer on the surface of the coatings and the experimental details will be presented.
FP21 Novel Synthesis of Conductive Nano-crystalline Carbon Film by Advanced Magnetron Sputtering
JeonGeon Han, SungI. Kim, JaeD. Nam (Sungkyunkwan University, South Korea)

Conductive carbon film attracts a great interest for application as electrode materials with its inherent chemical stability in various energy devices such as fuel cell and capacitor etc.. It is well known that conventional deposition processes by plasma including magnetron sputtering and PECVD at low temperature have been limited to synthesize carbon films with high conductivity comparable to that of conductive bulk or powder carbon materials with graphite structure. The design of film structure and process for synthesis of conductive carbon film is performed by energy model deposited onto the surface by control of various plasma parameters in magnetron sputtering, which is closely associated with process parameters. Nano-crystalline(nc) graphite clusters are then synthesized in the matrix of amorphous carbon, and conductivity of the film is therefore significantly enhanced. The conductivity is closely associated with proportion of nc graphite clusters and can be enhanced down to 2x10E-3 ohm.cm in our study.

This paper will discuss on the mechanism of energy deposition at the substrate surface during magnetron sputtering and corresponding changes of nucleation and growth of film with variation of process parameters during magnetron sputtering by integrated plasma diagnostics.

The mechanism of nc carbon film control is then discussed based on the film nucleation and growth theory for designed microstructure of various porosity and corresponding film properties in comparison with empirical data measured for the films deposited by magnetron sputtering with plasma control .

FP22 Reactive Sputtering Al2O3 and Cr2O3 Coatings using Arc Free High Power Pulsed Magnetron Sputtering
Jianliang Lin, William Sproul, Bo Wang, Yixiang Ou (Colorado School of Mines, US)
Deep oscillation magnetron sputtering (DOMS) is an alternative high power pulsed magnetron sputtering technique which offers virtually arc free depositions for reactive sputtering of insulating films at high target powers and currents. In this study, DOMS has been used to deposit Al2O3 and Cr2O3 coatings from either flow control or partial pressure control of the reactive gas with or without applying a RF substrate bias voltage. The hysteresis effects for the deposition process have been measured. The effects of the substrate temperature on the crystal structure of the coatings were investigated. It was found that dense and well crystallized Cr2O3 coatings can be obtained by DOMS without using external substrate heating. The coatings exhibited high hardness values between 25 GPa to 30 GPa and smooth surface. Approaches for obtaining crystalline Al2O3 coatings using DOMS at elevated substrate temperatures will also be presented. The microstructure, optical properties, mechanical and tribological properties of the oxide coatings deposited by DOMS were characterized and compared to those deposited using traditional pulsed dc magnetron sputtering.