ARNAM2006 Workshop Program

Changes and correction to: Elena Nobleza

Day 1 - Wednesday 28th June 2006
Registration and Coffee
9.00am - 10.30am
Opening Remarks - 10.30am - 10.45am
Session 1: Plenary Addresses 1 & 2
Session Chair: Jim Williams
10.45am - Barry Luther-Davies, ANU
Professor Barry Luther-Davies
ARC Federation Fellow
Professor/Head of Department, Laser Physics Centre Research School of Physical Sciences and Engineering Australian National University
Laser Physics Centre Research School of Physical Sciences and Engineering
Research Activities: Materials for photonic devices; hybrid organic-inorganic optical glasses; nonlinear optical materials; film deposition by pulsed laser ablation; nano-materials grown by pulsed laser ablation
"Nonlinear Optical Materials and Processes for Optical Communications Systems"Barry Luther-Davies - ANU

All-optical processing will be required if single channel data rates on optical fibres is to reach speeds around 160Gb/s. In this talk I will review the various materials available for all-optical processing outlining their advantages and disadvantages for this application.
11.30am - Peter Hodgson, Deakin
Professor Peter Hodgson
ARC Federation Fellow
Professor of Engineering, Assoc. Dean (Research) Faculty Science & Technology, School of Engineering & Technology, Deakin University
Engineering and Technology Faculty of Science and Technology School of Engineering and Technology Waurn Ponds Campus Deakin University
Research Activities: Thermomechanical Processing, Mathematical Modelling, Physical Metallurgy, Steels, Surface Treatment, Sheet Metal Forming
"Challenges for Research in Advanced Manufacturing"Peter Hodgson - Deakin University

The manufacturing industry is going through yet another period of great change. The rise of China and potentially India has altered the nature of the manufacturing industry in Australia. A number of companies have grown through this period by injecting more know how into the products they produce. In some cases this has led to them setting up major manufacturing plants overseas. Where does all of this leave those undertaking research in this sector? This has become a great challenge as we struggle to find the balance between basic research and innovative research.
Lunch Break - 1 hour
12.15pm - 1.15pm
Session 2: Opening Session
Session Chair: Liangchi Zhang
1.15pm - Ms Barbara Fairchild
Masters student
Shool of Physics University of Melbourne Parkville Victoria 3010
Research Activities: Micro machining in diamond

Material issues in the micro-fabrication and functionalization of single-crystal diamond

P. Olivero[1], A. Cimmino[1], M. Draganski[2], B. C. Gibson[3], Andrew D. Greentree[4], D. Hoxley[1], S. T. Huntington[3], A. Mancuso[1], J. Rabeau[1], P. Reichart[1], S. Rubanov[1], A. Stacey[1], E. Trajkov[3], I. Zalziniak[1], D. N. Jamieson[4], S. Prawer[4]

[1] School of Physics, Microanalytical Research Center, The University of Melbourne [2] RMIT, Dept. of Applied Physics, RMIT University Melbourne [3] Quantum Communication Victoria, School of Physics, The University of Melbourne [4] Centre for Quantum Computing Technology, School of Physics, The University of Melbourne

Diamond is known for its extreme physical properties (hardness, chemical inertness, thermal conductivity, optical transparency...), which make diamond microstructures extremely promising in integrated micro-optics, MEMS technology and micro-fluidics. Recently, the properties of optical centers in diamond have shown great potential for diamond nano-devices in quantum cryptography and quantum information processing. Significant progresses have been made in diamond growth and characterizationin the last decades. Nonetheless, the micro-fabrication of diamond, as well as the engineering and control of optical centers, are still challenging tasks where many material issues need to be taken into account, such as impurities and defects in different native crystals, radiation-matter interaction, annealing and etching behavior of pristine and irradiated diamond. We report on our activity in the microfabrication of micro-optics elements, cavities and resonators, and in the engineering and control of optical centers in diamond by ion and electron irradiation, with a focus on the fabrication of practical devices using our novel ion beam lithography technique than can produce micron and nano-scale diamond devices.

(Originally to have been presented by Rongping Wang who was unable to attend due to other research commitments)

Please send any changes or corrections to elena.nobleza@materials.com.au
1.35pm - Dr Alexander Fuerbach
ARC Postdoctoral Fellow
Centre for Ultrahigh-bandwidth Devices for Optical Systems (CUDOS) Centre for Lasers and Applications (CLA) Division of Information and Communication Sciences Macquarie University, Sydney, NSW 2109 Australia
Research Activities: Femtosecond-laser Micro- and Nanomachining, Fabrication of Photonic structures and Devices

High precision material processing using ultrashort laser pulses

Alexander Fuerbach*, Graham Marshall*, Martin Ams*, Nemanja Jovanovic*, Michael Withford*, Alma Fernandez†, Roswitha Graf†, Andreas Isemann‡, Thomas Mueller‡

*Macquarie University, Sydney †Max-Planck Institute of Quantum Optics, Garching, Germany ‡Femtolasers GmbH, Vienna, Austria

Laser micromachining using femtosecond pulses, is a most promising and versatile technique, having a variety of applications. The main features are an efficient and localized energy deposition, low ablation thresholds and no thermal and mechanical damage of the substrate material. The maximum benefits are obtained when one operates just above ablation or modification threshold. Under typical focusing conditions the required energies are 10s of nJ, which is slightly above the output of standard femtosecond oscillators. Amplified laser systems on the other hand are overkill for microstructuring as the pulse energy has to be strongly attenuated, resulting in a low average output power and process speed. This limits the achievable throughput and effects the overall process quality. The Chirped Pulsed Oscillator (CPO) is a new approach that resolves this problem. By adding a multipass cell into a standard oscillator, the cavity is extended. The low repetition rate results in pulse energies an order of magnitude higher. In contrast to a standard femtosecond oscillator, the CPO works in the positive dispersion regime whereby multiple pulsing is avoided. In this talk we will review the basic idea behind the CPO and will give an overview about the work we do at Macquarie University in the field of microfabrication of photonic structures and devices, aiming towards the development of the Photonic Chip. Amongst others, we will include our abilities in point-by-point inscription of fibre-Bragg gratings and the fabrication of waveguide structures in various materials, including laser-active crystals and chalcogenide glasses.

Please send any changes or corrections to elena.nobleza@materials.com.au
1.55pm - Dr Anthony Murphy
Senior Principal Research Scientist
CSIRO Industrial Physics PO Box 218 Lindfield NSW 2070 Australia
Research Activities: Development of semiconductor materials for photocatalytic splitting of water Optical properties of thin films and nanoparticles Plasma processing at atmospheric pressures (waste destruction, nanoparticle production, computational modelling) Transport properties of high-temperature gases and plasmas

Determination of optical properties of semiconductor thin films for photoelectrochemical water splitting

Anthony B Murphy

CSIRO Industrial Physics and CSIRO Energy Transformed National Research Flagship

In photoelectrochemical water splitting, hydrogen is produced in an electrochemical cell by the action of light on a photoelectrode, typically an oxide-semiconductor thin film on a conducting substrate. The semiconductor absorbs photons at wavelengths below its band-gap wavelength, producing electron–hole pairs. These charge carriers diffuse to the water and the conductor, driving the splitting of water into hydrogen and oxygen. Since the diffusion length of the charge carriers is small (~100 nm or less), it is important that the semiconductor has a large absorption coefficient for sub-band-gap wavelengths. I consider here the problem of determination of the band-gap and optical properties of a photoelectrode consisting of an optically-rough titanium-dioxide thin film on a titanium substrate. The diffuse reflectance of the photoelectrode was measured using a UV-Vis spectrophotometer. A two-flux (Kubelka–Munk) radiative transfer model, adapted to take into account reflection from optically-rough surfaces, was used to model the absorption and scattering of the radiation in the semiconductor film, and reflection at the semiconductor–air and semiconductor–metal interfaces. The dependence of the diffuse reflectance on parameters such as the absorption coefficient, scattering coefficient, film thickness and surface roughness was examined. The results show that determination of the semiconductor’s band gap from measurements of diffuse reflectance is by no means straightforward. Nevertheless, it was possible in some cases to derive the band gap, absorption coefficient and refractive index of the semiconductor, using a spectral-projected-gradient method to fit the model to the measured diffuse reflectance.

Please send any changes or corrections to elena.nobleza@materials.com.au
2.15pm - Dr Simon Ruffell
Postdoctoral Research Fellow
Department of Electronic Materials Engineering Research School of Physical Sciences and Engineering Australian National University Canberra, 0200 Australia
Research Activities: Ion-implantation, ion-beam analysis, low energy implants in silicon, defects and dopants in semiconductors Nanoindentation of semiconductors, pressure-induced phase transformations in silicon

Study of the kinetics of phase transformations on unloading during nanoindentation of silicon

S. Ruffell, J. E. Bradby, and J. S. Williams

Department of Electronic Materials Engineering, Research School of Physical Sciences and Engineering, Australian National University, Canberra, 0200, Australia

Silicon undergoes a series of pressure-induced phase transformations during nanoindentation. On loading, at a pressure of ~12 GPa, a transformation to a metallic phase occurs with further transformations to the crystalline phases (Si-III and Si-XII) or amorphous silicon (a-Si) occurring on pressure release. The post-indentation phases are dependent on the unloading conditions with slower rates promoting the formation of the crystalline phases. The effect of unloading conditions on the final structure has been studied in detail but the mechanisms driving the process are relatively poorly understood. Indentations in both crystalline (c-Si) and (ion-implanted) amorphous silicon have been studied via a combination of Raman micro-spectroscopy and cross-sectional transmission electron microscopy where samples prepared by a focused ion beam milling method can be imaged and directly correlated with the Raman spectra and nanoindentation load/unload curves. Rapid unloading during indentation in c-Si has been previously shown to result in only a-Si being formed, an outcome we have exploited to track the high pressure phase transformations by unloading rapidly from selected points on the unload curve. Stark differences in the initial formation and subsequent growth of volumes of high pressure phases on unloading are observed when comparing the residual phases in c-Si and a-Si, with high pressure phases forming much more readily in a-Si.

Please send any changes or corrections to elena.nobleza@materials.com.au
2.35pm - Professor Barry Luther-Davies
ARC Federation Fellow
Professor/Head of Department, Laser Physics Centre Research School of Physical Sciences and Engineering Australian National University
Laser Physics Centre Research School of Physical Sciences and Engineering
Research Activities: Materials for photonic devices; hybrid organic-inorganic optical glasses; nonlinear optical materials; film deposition by pulsed laser ablation; nano-materials grown by pulsed laser ablation

Impact of Annealing Temperature on Ultra Fast Pulsed Laser Deposited As2S3

R P Wang, C. Zha, S. Madden, A. Rode, B. Luther-Davies, R. Jarvis

Laser Physics Centre, RSPhysSE, ANU

Amorphous chalcogenide glases are being studied for their use in all-optical processing for future high speed telecommunications networks. Unfortunately chalcogenides films dsiplay properties quite different from the bulk glasses and this manifests itself in various instabiltiies in the bond structure when the films are subjected to heat or light. Here we report on the properties of films prepared by ultra-fast pulsed laser deposition which have been vacuum annealed at a range of different temperatures. Measurements of the glass transition temperature indicate that a crystallization process initiates at annealing temperatures around 170C. In combination with Raman scattering analysis, we conclude that phase separation is intrinsic for our as-deposited films. During annealing two sorts of phase transformation are identified: one between different amorphous polymorphs, and another from the amorphous to a crystalline state. We point out a correlation between these two types of transformation and two characteristic time scales identified from measurements of the relaxation of the refractive index, and explain the Arrhenius and non-Arrhenius behaviour leading to the observed temporal characteristics.

(Originally to have been presented by Rongping Wang who was unable to attend due to other research commitments)

Please send any changes or corrections to elena.nobleza@materials.com.au
2.55pm - Dr Mihail Ionescu
Senior Research Scientist, Ion Beam Accelerator, ANSTO
ANSTO New Illawarra Rd Lucas Heights NSW 2234
Research Activities: Ion Beam Accelerator Applications (RBS, PIXE, PIGE, PESA, RToF, ERDA, NRA, ion beam implantation) Thin film deposition (PLD, EBE, MS) Thin film characterization (phisical, electric and magnetic properties)

Total Hydrogen in SiNx thin films

M. Ionescu*, B. Richards†, K. McIntosh†, R. Siegele*, E. Stelcer*, D. Cohen*

*ANSTO †ANU

Thin SiN film deposited on Si by plasma enhanced chemical vapour deposition (PECVD) is used for surface passivation of Si. During the PECVD process Hydrogen is incorporated into the SiN film, and the passivation properties of the resulting SiNx:H layers play an important role in enhancing the energy conversion efficiency of solar cells. It is believed that the Hydrogen present in SiNx:H is responsible for this enhancement, and therefore its concentration in the passivating layer is an important parameter. The Hydrogen composition and its depth profile in thin SiNx:H films of 10nm to 200nm was measured by elastic recoil detection analysis (ERDA), using a 1.7MeV He+ ion beam of (1x2)mm2, generated by a high stability 2MV Tandetron ion beam accelerator. In the same time, Rutherford backscattering spectroscopy (RBS) spectra were recorded for each sample. The results show that Hydrogen concentration in the SiNx:H layers is dependent of the deposition conditions. Also, Hydrogen was found to be homogenously distributed across the SiNx:H layer thickness, and the SiNx:H/Si interfaces were well defined.

Please send any changes or corrections to elena.nobleza@materials.com.au
10.50am - Dr Jamie Quinton

School of Chemistry, Physics & Earth Sciences Flinders University GPO Box 2100 Adelaide SA 5001
Research Activities: Surface science Organosilicon coatings Thin films Surface modification

Plasma Modified Carbon Surfaces for Novel Sensor Supports

J.S. Quinton1*, A. Deslandes1, A. Barlow1, J.J. Gooding2, D.B. Hibbert2

1. Smart Surface Structures Group, School of Chemistry, Physics and Earth Sciences, Flinders University, GPO Box 2100 Adelaide, SA, 5001, Australia 2. Electroanalytical and Sensors Group, School of Chemistry, University of New South Wales, Sydney, NSW, 2052, Australia

Surface modification is used to alter the surface properties of a given material to enhance its favourability for a given application. This important aspect of all material applications is essential for optimal performance and working lifetime. In modern nanotechnological applications for materials, modified surfaces tend to be ‘active’ in that they serve a functional purpose (such as sensing, enhancing wettability, preventing bacterial growth, etc), rather than simply serving as an improved form of passivation. In collaboration between our laboratories, we are presently working on various carbon (Highly ordered pyrolytic graphite – HOPG, nanotubes and glassy carbon) surfaces as a new substrate of choice for the preparation of new, novel biological and chemical sensing devices. Flinders role within this project involves modification of these carbon surfaces with various plasma treatments, in preparation for subsequent attachment of sensing architectures. I will highlight our work to date, which has focussed on the surface modification of HOPG and carbon nanotubes with various plasma (CH4, H2, SF6) treatments, followed by characterisation with techniques such as scanning tunnelling microscopy (STM), X-ray Photoelectron Spectroscopy (XPS) and Time of Flight Secondary Ion Mass Spectrometry (ToFSIMS). *email: Jamie.Quinton@flinders.edu.au

Please send any changes or corrections to elena.nobleza@materials.com.au
Afternoon Tea Break - ½ hour
3.15pm - 3.45pm
Session 3: Polymers/Polymer composites
Session Chair: Graham Shaffer
3.45pm - Professor Geoffrey Spinks
Discipline Advisor, School of Mechanical, Materials & Mechatronic Engineering, University of Wollongong

Research Activities: Mechanical properties of polymers, coatings and adhesives, mechanical actuators and sensors for structural health monitoring.

Polymer artificial muscles- current status and applications

G.M. Spinks, P.G. Whitten, B. Xi, V. Mottaghitalab, M. Barami-Samani, G.G. Wallace,

ARC Centre of Excellence in Electromaterials Science, Intelligent Polymer Research Institute, University of Wollongong

Polymer artificial muscles are attractive alternatives to conventional mechanical systems (motors, engines, hydraulics and pneumatics) in applications where space/weight are important. The presentation will review the performance of various polymer actuators and consider recent developments in conducting polymer, carbon nanotube and hydrogel actuators. Various potential applications will also be described.

Please send any changes or corrections to elena.nobleza@materials.com.au
4.05pm - Miss Celeste Gloria-Esparza

Department of Mechanical & Manufacturing Engineering The University of Melbourne Victoria 3010 Australia
Research Activities: conduct experiment work to develop an electrially condcutive polymer nanocomposites

Electrically Conductive Glass Fiber Reinforced Nanocomposites

Celeste Gloria Esparza (1), Qiang Yuan(2), Kenong Xia(1)

(1) University of MElbourne (2) CSIRO

Electrically conductive composites were made from short glass fiber (GF) and carbon black (CB) blended with high-density polyethylene (HDPE) using a single screw extruder. Mechanical Properties were highly enhanced and Percolation threshold was lowered by the addition of Glass Fiber achieving surface conductivity in the static dissipative range of 10-6 to 10-9 S at CB content as low as 1 wt.%, significantly lower than that in the unreinforced CB/HDPE. Addition of coupling agents like MAPE and GMA improved bonding between fibers and the polymer matrix and increased the stiffness and fracture resistance.

Please send any changes or corrections to elena.nobleza@materials.com.au
4.25pm - Mr Indra Kemal
PhD student / Researcher at UNSW

Research Activities:

Development of PVC nanocomposites

A/Prof. Mark Hoffman

School of Materials Science and Engineering The University of New South Wales, Sydney

Recent progress of nano processing technology has enabled production of nano particles of Calcium Carbonates in commercial scales. It has been demonstrated that presence of inorganic nanoparticles could improve toughness of PVC properties when the particles are homogeneously distributed. However, integrating this technology into current manufacturing process has brought another challenge in achieving fine particles dispersion. In this study, PVC/CaCO3 polymer nanocomposites were made by two roll mills and twin screw extruder. TEM micrographs of the two different processing will be shown to indicate which processing give better dispersion.

Please send any changes or corrections to elena.nobleza@materials.com.au
4.45pm - Mr Jian Fang
PhD Student
Centre for Material and Fibre Innovation Geelong Technology Precinct (GTP) School of Engineering and Technology Deakin University, Pigdons Rd. Waurn Ponds, Geelong, VIC, 3217, Australia
Research Activities: functionized textile materials

Toughened Electrospun Nanofibres from a Thermoplastic and a Crosslinkable Elastomer Blend

Jian Fang, Tong Lin, Xungai Wang

Centre for Material and Fibre Innovation, Faculty of Science and Technology, Deakin University, Geelong, Vic 3217

A polymer blend of polyacrylonitrile (PAN) and a crosslinkable elastomeric polyester urethane (PEU) was electrospun into nanofibres. The effects of the PAN/PEU ratio and the crosslinking reaction on fibre morphology and the tensile properties were investigated. When the overall polymer concentration was kept constant during electrospinning, the variation of the PAN/PEU ratio had a little effect on the fibre morphology. With an increase in the PEU composition, the fibre diameter decreased slightly, but the tensile strength and the ultimate strain increased. An interconnected web structure was formed when the polymer blend contained a high PEU composition. The slight crosslinked PEU in the PAN/PEU blend noticeably improved the tensile strength and the ultimate strain.

Please send any changes or corrections to elena.nobleza@materials.com.au
5.05pm - Dr Jamie Booth
Postdoctoral Fellow
Commonwealth Scientific and Industrial Research Organisation, Manufacturing and Infrastructure Technology, Locked Bag 33, Clayton South, Victoria 3169
Research Activities: Sol-Gel Materials Science Nanoparticle Nucleation and Growth Combinatorial Design X-ray Structural Characterisation

A Rehological Investigation of the Inhibition of Hydrolytic Polycondensation of Titanium Butoxide by Protons

Jamie M Booth, CSIRO Manufacturing and Infrastructure Technology

Colin J Rix School of Applied Sciences (Applied Chemistry), Science, Engineering and Technology Portfolio, RMIT University

The high reactivities of transition metal alkoxides with respect to hydrolytic polycondensation, i.e. the sol-gel process, are well known. In order to gain control over the kinetics, and thus the morphologies of the resultant products, methods such as complexation by acetylacetone or 2-methoxyethanol have been employed with some success. However, an equally effective method is the addition of a small amount of an inorganic acid such as HCl. While efforts have been made to determine the mechanism by which the added protons retard the reaction rate, none have proposed a mechanism consistent with all of the available experimental data. The study described herein presents the first rigorous rheological characterization of the sol-gel process for titanium tetra-n-butoxide, and the data obtained allow a new mechanism to be formulated which is consistent with all experimental evidence.

Please send any changes or corrections to elena.nobleza@materials.com.au
5.25pm - Mr Aravind Dasari
PhD Student
Center for Advanced Materials Technology (CAMT) School of Aerospace, Mechanical, and Mechatronic Engineering (Bldg. J07) The University of Sydney Sydney, New South Wales 2006 Australia
Research Activities: • Tribology of polymer nanocomposites at different length scales • Structure-property relationships in polymer nanocomposites • Fracture behaviour of polymers

The Location and Extent of Exfoliation of Clay on the Fracture Mechanisms in Nylon 66-Based Ternary Nanocomposites

Mr. Aravind Dasari, Dr. Zhong-Zhen Yu, Prof. Yiu-Wing Mai

The University of Sydney, NSW 2006, Australia

The primary focus of this work is to elucidate the location and extent of exfoliation of clay during the fracture (under both static and dynamic loading conditions) of melt-compounded nylon 66/clay/SEBS-g-MA ternary nanocomposites prepared by different blending sequences. Distinct microstructures are obtained depending on the blending protocol employed. The state of exfoliation and dispersion of clay in nylon 66 matrix and SEBS-g-MA phase are quantified as the presence of clay in rubber is shown to have negative affect on the fracture toughness of the nanocomposites. The level of enhancement in fracture toughness of the ternary nanocomposites is found to depend on the capability of different fillers to activate the plastic deformation mechanisms in the matrix and the blending protocol employed. These mechanisms included: cavitation of the SEBS-g-MA phase, stretching of the voided matrix material, interfacial debonding of SEBS-g-MA particles, debonding of intercalated clay present inside the SEBS-g-MA phase, and delamination of intercalated clay platelets. Based on these results, some new insights and approaches for producing better toughened polymer ternary nanocomposites will be discussed.

Please send any changes or corrections to elena.nobleza@materials.com.au
Session 4: Materials Structures/Fabrication
Session Chair: Barry Luther-Davies
3.45pm - Mr Shannon Orbons
PhD Student
Rm 210 School of Physics University of Melbourne 3010 Victoria
Research Activities: Nanofabrication, Characterization of Novel Optical Materials and Computational Modelling

Ion Beam Fabrication and Characterization of 3D Periodic Nanoscale Materials

S. M. Orbons1, L van Dijk2,3, M Bozkurt2,3, P N Johnston2, P Reichart1, D N Jamieson1

(1) School of Physics, University of Melbourne, Victoria 3010, Australia (2)Department of Applied Physics, Eindhoven University of Technology, The Netherlands (3)Applied Physics, RMIT University, GPO Box 2476V, Victoria 3001, Australia

The demand for 3D periodic nanoscale materials in photonic systems is ever increasing. However, traditional analytical techniques of nanoscale systems such as Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM), cannot provide any sub-surface information or elemental analysis, without destructive cross sectioning of the sample. In this work, a high aspect ratio sub-m periodic structure fabricated by Focused Ion Beam (FIB) lithography is characterized by Rutherford Backscattering Spectrometry (RBS) using the macrochannelling technique. The technique overcomes the limitations of complementary techniques such as (SEM) and (AFM) by providing sub-surface elemental analysis of periodic materials. The diffraction grating under investigation consists of an array of 100 nm wide trenches in a 300 nm thick Ag film on a Si substrate. Using the surface structure imaged by SEM and AFM as a starting point, a numerical model for the RBS spectrum from the grating is fitted to the experimental spectrum as a function of the sub-surface structure. This process allows the width of the trenches to be determined as a function of depth even though the lateral structure is not resolved by the ion beam.The demand for 3D periodic nanoscale materials in photonic systems is ever increasing. However, traditional analytical techniques of nanoscale systems such as Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM), cannot provide any sub-surface information or elemental analysis, without destructive cross sectioning of the sample. In this work, a high aspect ratio sub-m periodic structure fabricated by Focused Ion Beam (FIB) lithography is characterized by Rutherford Backscattering Spectrometry (RBS) using the macrochannelling technique. The technique overcomes the limitations of complementary techniques such as (SEM) and (AFM) by providing sub-surface elemental analysis of periodic materials. The diffraction grating under investigation consists of an array of 100 nm wide trenches in a 300 nm thick Ag film on a Si substrate. Using the surface structure imaged by SEM and AFM as a starting point, a numerical model for the RBS spectrum from the grating is fitted to the experimental spectrum as a function of the sub-surface structure. This process allows the width of the trenches to be determined as a function of depth even though the lateral structure is not resolved by the ion beam.

Please send any changes or corrections to elena.nobleza@materials.com.au
4.05pm - Dr Paul Stoddart
Research Fellow
Swinburne University of Technology Mail H38 - CAOUS PO Box 218 Hawthorn VIC 3122
Research Activities: Optical fibre chemical sensors Optical fibre distributed sensors Fibre Bragg grating sensors Synchrotron radiation for optical materials processing 3D shape measurement of specular surfaces Bacterial adhesion on textured surfaces Sub-wavelength anti-reflection coatings Miniature spectrometers

Synchrotron Radiation for Lithography and Optical Materials Processing

Paul R. Stoddart(1), Scott A. Wade(2), Ben Smith(1), Peter Kemeny(3)

(1)Centre for Atom Optics and Ultrafast Spectroscopy, Swinburne University of Technology (2)Department of Mechanical Engineering, Monash University (3) Kemeny Consulting

The need for deep sub-micron resolution has driven the development of various “next generation” lithographic techniques, amongst which X-ray lithography (XRL) has emerged as a leading candidate. Although the relatively weak interaction between X-rays and optical elements and photoresists presents a major challenge, XRL techniques based on the collimated flux from a synchrotron storage ring are gaining in popularity. In particular, high aspect ratio structures with very smooth sidewalls can be produced by exposing relatively thick layers of resist with energetic X-rays (7-20 keV). These structural characteristics are particularly useful for the fabrication of photonic devices and a range of recent applications are reviewed. We also discuss the potential for the fabrication of Bragg gratings in optical waveguide devices by means of synchrotron radiation. Although it has been known since at least 1953 that the refractive index of silica can be modified by energetic radiation, it appears that synchrotron light has not yet been used to fabricate optical devices in this way. The refractive index modification has been attributed to a compaction process similar to that observed in silicate glasses exposed to UV radiation with energy greater than the 8 eV band gap. The compaction process offers a number of advantages for the fabrication of Bragg gratings and waveguides. Finally, we discuss some preliminary modelling results relevant to the direct writing of refractive index structures with synchrotron radiation.

Please send any changes or corrections to elena.nobleza@materials.com.au
4.25pm - Dr Zonghan Xie
ARC Postdoctoral Fellow, School of Materials Science and Engineering, University of New South Wales
School of Materials Science and Engineering University of New South Wales NSW 2052, Australia
Research Activities: Effect of microstructure on contact deformation and wear behaviour of ceramics; deformation of hard coatings

Deformation and Fracture Behaviour of Mono- and Multilayered TiN Coatings on Steel Substrates

Z. H. Xie 1, M. Hoffman 1, R. K. Singh 1, P. Munroe 1, A. Bendavid 2 and P. J. Martin 2

1 School of Materials Science and Engineering The University of New South Wales, Sydney, NSW 2052, Australia 2 CSIRO Division of Industrial Physics, PO Box 218, Lindfield, NSW 2070, Australia

TiN coatings have been widely applied onto metallic materials to provide protection against contact damage. An understanding of the behaviour of these coating systems subject to mechanical loading is therefore essential for improving their reliability and durability. This presentation will examine the controlling mechanisms of two typical TiN coating systems, i.e. mono- and multi-layered TiN coatings during micro-indentation and micro-scratch testing. A depth-sensing indentation instrument, equipped with a spherical-tipped conical indenter of 5 micrometer tip radius, was used to introduce deformation and fracture in these coating systems. Cross-sections of the indents were prepared and examined using a state-of-the-art dual ion/electron beam system. Cross-sectional TEM analyses were also conducted to reveal the interactions between cracks and coating microstructure. Based upon the observations, models were developed to understand the effects of coating microstructure, architecture (i.e. structural layering) and interlayer material properties upon the deformation and fracture behaviour of TiN coating systems.

Please send any changes or corrections to elena.nobleza@materials.com.au
4.45pm - Mr Warren McKenzie
PhD Student
Electron Microscope Unit Basement - Red Centre West Wing University of New South Wales Sydney NSW 2052
Research Activities: Dual Beam FIB, TEM, XRD, AFM and Raman analysis of Silicon on Sapphire thin films.

Microstructural Improvement of Silicon-on-Sapphire Thin Films for Integrated Circuit applications

W.R. McKenzie* and P.R. Munroe*, H. Domyo† and T. Ho†

*School of Materials Science and Engineering, University of New South Wales, SYDNEY, NSW 2052, Australia, †Peregrine Semiconductor Australia Pty Ltd, HOMEBUSH, NSW 2140 Australia

Silicon-on-Sapphire (SOS) technologies offer many advantages over conventional bulk silicon in the performance of integrated circuits (IC’s) for radio frequency and microwave applications as the devices are significantly more radiation hard. SOS thin films, grown by chemical vapour deposition (CVD), are subject to a solid phase epitaxial re-growth (SPER) process to improve the quality of the silicon film to a level suitable device processing [1]. This paper studies the evolution of crystalline defects during the CVD and SPER processes. Understanding the evolution of the types and the locations of defects will aid in further improvements of the process currently aiming to support deep submicron device fabrication. Most of the developments of the SPER process since its inception have relied on electrical measurements to quantify crystalline quality. This study utilises the TEM to identify actual types of crystalline defects and their respective densities at different stages of the SPER process. For many of these defects, their origins and termination mechanisms have been identified. Based on these observations, optimisations of the SPER process have been suggested. 1. S.S. Lau, S. Matteson, J.W. Mayer, P. Revesz, J. Gyulai, J. Roth, T.W. Sigmon and T. Cass, Appl. Phys. Lett. 34(1) (1979) pp. 76-78.

Please send any changes or corrections to elena.nobleza@materials.com.au
5.05pm - Professor Nunzio Motta
Adjunct Professor
School of Engineering Systems "O" Block, Level 7, Room O711 Queensland University of Technology (G.P.) 2 George Street, BRISBANE Qld 4001
Research Activities: Growth and characterization of Ge/Si quantum dots and nanostructures. Nanotube-Polymer composites for solar cells.

Towards nanomemories: Ge growth on naturally and artificially nanostructured Si surfaces

Nunzio Motta*, Anna Sgarlata**, P.D.Szkutnik**, A.Balzarotti**, Federico Rosei***, Isabelle Berbezier****

*School of Engineering Systems, Queensland University of Technology, GPO box 2434 Brisbane, Australia 4001 **Dipartimento di Fisica, Università di Roma Tor Vergata, Via della Ricerca Scientifica 1, 00133 Roma (Italy). ***INRS - Varennes (Canada) ****LM2P – Universite’ d’Aix –Marseille 2 (France)

Quantum dots (QDs) grown on semiconductors surfaces are actually the main researchers' interest for applications in the forecoming nanotechnology era. New frontiers in nanodevice technology rely on the precise positioning of the nucleation site and on controlling the shape and size of the dots. Novel approaches to form ordered patterns of homogeneous nanostructures are explored: natural patterning induced by surface instabilities (as step bunching of Si(111) or misoriented Si(001) surfaces), standard patterning with high resolution lithographic techniques, implantation of Ga+ ions by Focused Ion Beam (FIB), or in situ substrate patterning by Scanning Tunneling Microscopy (STM). Based on the analysis of STM images we report on growth and arrangement of Ge islands on Si(001) substrates nanopatterned using several different approaches. The first is a natural method based on the regular step bunching that occurs on Si(111) surfaces with different annealing treatments. The second is based on the self organization of a Si(001) misoriented surface covered by a thin layer of a GeSi alloy. The third exploit an array of holes produced by STM lithography. The forth is a tight pattern created by FIB. We analyze the resulting distribution of islands resulting from all these approaches

Please send any changes or corrections to elena.nobleza@materials.com.au
5.25pm - Dr Jingxian Yu
Student
School of Chemistry, Physics & Earth Sciences Flinders University GPO Box 2100 Adelaide SA 5001
Research Activities: Silicon based nanostructured materials

Molecular Memories using Hybrid Ferrocene/Porphyrin Monolayers

Jingxian Yu, Simon Mathew, Joseph Shapter, Jamie Quinton and Martin Johnston

School of Chemistry, Physics and Earth Sciences, Flinders University of South Australia, Adelaide, SA 5042, Australia

During the past decade there has been an increasing interest in developing molecular-based memory devices. Approaches made toward this goal have generally involved the attachment of a collection of redox-active molecules (such as, porphyrin and ferrocene materials) to an electroactive surface (such as silicon). The redox-active materials serve as the active storage medium, with information stored in the discrete redox states of the molecules. In our paper we will present results of self-assembled monolayers composed of a mixture of ferrocene and porphyrin molecules. Through attachment of ferrocenecarboxylic acid and 5-(4-carboxyphenyl)-10,15,20-[tris(3,5-ditertbutylphenyl)] prophyrin to the terminal hydroxyl groups on the silicon surface, we will demonstrate how these SAMs are excellent candidates for molecular memory devices.

Please send any changes or corrections to elena.nobleza@materials.com.au
Session 5: Poster Presentation Session
· Mr. Alireza Asgari, Deakin
PhD Student

Research Activities: Multiscale modelling of TRIP steel

Multiscale modelling of hardening mechanisms and phase transformation in TRIP steel" Alireza Asgari, Bernard Rolfe, Peter Hodgson

Centre for Material and Fibre Innovation, Faculty of Science and Technology, Deakin University Geelong, Victoria, Australia, 3217

The numerical modelling codes currently used for forming, springback and crash modelling generally represent the sheet as homogenous material, uniform in thickness and material properties and use a continuum mechanics approach to simulate dynamic deformation processes. The assumptions of continuum mechanics are accurate enough for conventional steels where the effects of molecular processes are represented by the equations of state and the constitutive relations. These effective models, which are mostly empirical, have their limitations when complex structural steels are investigated. One of these limitations, besides generally poor accuracy, is the complete neglect of the microscale mechanisms which are of great importance in the case of Advanced High Strength Steels (AHSS), such as TRansformation Induced Plasticity (TRIP) steels. The option of just using microscale modelling methods, which have better accuracy and a physical foundation, is not the best answer. The reason ! is that the models are often too complex and the answers we get will likely contain too much information that is of little interest, further complicating the task of extracting useful data. However, multiscale modelling can efficiently improve the AHSS model predictions, by taking into account the profound effects of microstructural details such as nonlinearities, deformation induced phase transformation and history dependent large deformation. In this presentation, the path to build a multiscale modelling framework based on the hybrid Finite Element/Particle-in-Cell method is presented. This framework can be used to study the effect of hardening mechanisms and phase transformation of TRIP steel in micro scale toward simulation of macro scale metal forming processes.

· Dr Hossein Beladi, Deakin
Research Fellow
Centre for Material and Fibre Innovation GTP Building, Deakin University Geelong, VIC 3217
Research Activities:

Dynamic Strain-Induced Transformation of Bainite" H. Beladi1, Y. Adachi2, M. Wakita3 and P. D. Hodgson1

1. Centre for Materials and Fibre Innovations, Faculty of Science and Technology, Deakin University, Geelong, Australia, VIC 3216 2. National Institute of Materials Science, 1-2-1 Sengen, Tsukuba-Shi, Ibaraki, 305-0047, Japan 3. Sumitomo Metal Industries, Ltd., 1-8 Fuso-cho, Amagasaki 660-0891, Japan

The excellent balance between strength and ductility is a key characteristic of steels compared with other metals. Recently, the costumer demands worldwide for superior mechanical properties have led to new research to further engineer the microstructures of steels. Among the different strengthening mechanisms, refinement of microstructure (such as ferrite and bainite) is the most promising way to improve the strength of steel without sacrificing the toughness. Of the approaches to date, the use of dynamic strain-induced transformation (i.e. inducing the austenite to ferrite transformation during deformation) has shown the greatest potential, with grain sizes of the order of 1µm or less being achieved. However, these high strength ultrafine ferritic microstructures suffer from limited ductility. Dynamic strain-induced transformation is potentially a promising approach to ultrafine bainite structure since the bainite transformation has a similar reaction to the ferrite transformation (i.e. nucleation and growth). In the current study, 0.2C-2Mn steel with high hardanbility was used to investigate the concurrent deformation and bainite transformation using compression testing. The results suggested that the bainite formation was accelerated by deformation at the early stage of transformation resulting fine ferritic bainite. However, the austenite was then stabilized through further transformation resulting retained austenite and martensite at room temperature. The retained austenite characteristics (i.e. volume fraction, size and distribution) can be controlled through thermomechanical parameters to improve the mechanical properties of steel.

· Mr Ivan Blajer, UTS
PhD Student

Research Activities: Polymer optical fibres manufacture, microstructured fibres, imaging,

Method for casting microstructured polymer fibre preforms." I.Blajer, J. Franklin, G.B. Smith

Applied Physics, University of Technology, Sydney, Broadway, Ultimo NSW 2007

We report on an inexpensive method for producing optical quality microstructured pre-forms for production of optical fibre. This is achieved by polymerisation of PMMA in a specially designed mould and subsequent extraction of the finished pre-form. The successful production of the preform requires careful monitoring and control of the polymerisation reaction of the methyl methacrylate monomer. The transverse structure complicates the dynamics of the reaction. Maximum homogeneity of the final product is needed with avoidance of local stresss variations during growth . This varies between samples depending on the number of air channels in the pre-form. We report on the achieved optical losses and qualitative properties of the preform. The advantages and disadvantages of this method compared to others are also outlined.

· Mr Adam Brancher, Griffith
PhD Student- Griffith University Gold Coast Campus
Semaphore Adelaide South Australia 5019
Research Activities: Writing PhD part time at Griffith University, Gold coast QLD on active non-destructive testing of marine fibre compsites using neural network evaluation.

Innovating Small Craft Manufacturing In Australia" A C Brancher, H Zhao, S Zhang

Griffith University

Production composite boat building in Australia has, with few exceptions, not progressed from the original 'bucket and brush' technology developed in the 1960's. This technology is wasteful, environmentally questionable,and often results in poorly engineered structures. Solutions to these issues are emerging in other parts of the world and this paper argues that they merit examination if the Australian industry is to meet its potential.

· Dr Kristin Carpenter, UWollongong
Research Fellow
Faculty of Engineering University of Wollongong Northfields Av Wollongong 2522 Australia
Research Activities: Research for product and process improvement for continuous casting of steel. Conventional Strip casting, Hot ductility testing (Gleeble 3500)

The hot ductility of Nb, Ti, Nb-Ti microalloyed steels and the influence of thermal history on ductility for the Nb-Ti steel." K.R. Carpenter, R. Dippenaar and C.R. Killmore*

Process Engineering Group, University of Wollongong, Wollongong NSW 2522, Australia *BlueScope Steel, Central Laboratory, Port Kembla NSW 2505, Australia.

The hot-ductility of Nb, Ti and Nb-Ti containing steels have been studied under direct-cast conditions and the influence of thermal oscillations on the ductility of Nb-Ti steel was investigated. A Gleeble 3500 thermomechanical simulator was used to determine hot-ductility over the temperature range 1100-700C at a low strain rate of 7.5 x 10-4 s-1. Tensile samples were melted and solidified ‘in-situ’ to simulate direct casting and were subsequently cooled at two different cooling rates, 100K/min and 200K/min, simulating respectively, the cooling rate of thick and thin slab casting processes. Complex thermal patterns designed to simulate the cooling conditions experienced near the surface of a slab during continuous casting were performed for the Nb-Ti steel. The addition of thermal oscillations to hot ductility tests improves the tests accuracy in the simulation transverse cracking during unbending in the continuous casting of troublesome peritectic steels. The Nb-Ti steel had lower ductility than both the Nb and Ti steels. Increasing the cooling rate generally deteriorated ductility. The low recovery of ductility at higher temperatures was explained in terms of a low strain rate and fine precipitation delaying the onset of dynamic recrystallisation, which can promote intergranular cracking because of grain boundary sliding in austenite. At lower temperatures, the ductility decreased further due to the formation of thin ferrite films at the prior austenite grain boundaries. Simulating the thermal history experienced near the surface of thin (90mm) cast slab improved ductility of the Nb-Ti steel by promoting coarser NbTi(C,N).

· Ms Chanokporn Chaiwong, USyd

Applied and Plasma Physics, School of Physics, A28 The University of Sydney, NSW 2006
Research Activities: - Plasma Immersion Ion Implantation and Deposition (PIII&D) for thin film deposition on polymeric materials - Ion Implantation for optical property modification

Effects of the interface region on the adhesion of titanium nitride films grown by plasma immersion ion implantation onto polymer substrates" C. Chaiwong, D.R. McKenzie, M.M.M. Bilek

School of Physics, A28, The University of Sydney, NSW 2006, Australia

Adhesion is a major factor in coating performance. The interface region is of special interest since it is usually the site of adhesion failure. Titanium nitride films were deposited onto polymer substrate by filtered cathodic vacuum arc using the plasma immersion ion implantation (PIII&D) method. Tensile testing was used to ascertain and quantify the strength of the film adhesion. It was found that films grown by PIII&D showed excellent adhesion, comparable to that usual for TiN deposited onto stainless steel. The interfaces and microstructures of the films produced were analysed using cross-sectional TEM to determine the mechanisms by which the film bonds to the polymer.

· Mr. Xiaobo Chen, Deakin
postgraduate student
Geelong Technology Precinct, Deakin Uni. Pigdons Rd. Waurn Ponds, 3217 VIC
Research Activities:

Preparation of bioactive TiZr alloys via thermo-chemical surface pretreatments" X.B. Chen*, A. Nouri, X.J. Wang, P.D. Hodgson and C.E. Wen,

Material and Fiber Innovation, Deakin University

TiZr alloys have a high potential for biomedical applications due to the excellent biocompatibility of both elements of titanium and zirconium. Nevertheless, the surfaces of the TiZr alloys need to be modified by proper way in order to impart the implant materials bioactivity and therefore, eliminate the adverse reaction and shorten the implant-tissue osseointegration time. In the present study, a thermo-chemical pretreatment process followed by the soaking in simulated body fluid (SBF) were performed for the preparation of the bioactive TiZr alloys which exhibit a hydroxyapatite (HA) layer on the surface. Phase transformation, surface morphology, and interfacial microstructure were investigated using optical microscopy, hardness tester and SEM-EDS techniques.

· Mrs Yiqing Chen, USyd
PhD student
School of Aerospace, Mechanical and Mechatronic Engineering University of Sydney NSW 2006 Australia
Research Activities:

Polishing of Polycrystalline Diamond" Y. Chen , L. C. Zhang, J. A. Arsecularatne

School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, Sydney NSW 2006, Australia

Dynamic friction polishing (DFP) utilizes thermo-chemical reaction between a diamond surface and a metal disk tool rotating at a high peripheral speed and enables highly efficient polishing of polycrystalline diamond (PCD). Based on the experimental analyses, the material removal mechanisms can be described as: conversion of diamond carbon into non-diamond carbon by friction heating and contacting with catalytic metals; removal of these non-diamond carbon mechanically, and/or diffusion of carbon atoms into a counterpart metal, and/or oxidization of carbon and evaporation in the form of CO or CO2 gas.

· Miss Suk Chin, UWA
PhD student
The University of Western Australia The University of Western Australia School of Biomedical & Chemical Sciences 35 Stirling Highway Crawley WA 6009 Australia
Research Activities: Synthesis and Characterization of Magnetic Nanoparticles for Biomedical Application

Encapsulation of Magnetic Nanoparticles with Biopolymer for Biomedical Application" Suk Fun Chin, Mohamed Makha, Colin Raston

School of Biomedical, Biomolecular and Chemical Sciences University of Western Australia, Crawley, Western Australia 6009

Magnetic nanoparticles have been extensively studied because of their potential applications as contrast agents in magnetic resonance imaging (MRI) of tumors, cell and DNA separation, magnetically guided drug delivery, tumor hyperthermia etc. Among the magnetic oxides, magnetite nanoparticles are most suitable due to their low toxicity and good magnetic properties. Magnetite is a ferromagnetic iron oxide, Fe3O4 with an inverse spinel crystalline structure in which part of the iron atoms are octahedrally coordinated to oxygen and the rest are tetrahedrally coordinated to oxygen. However, magnetite tends to aggregate due to strong magnetic dipole-dipole attractions between particles combined with inherently large surface energy. In this study, we attempt to encapsulate magnetite nanoparticles with chitosan derivatives using Spinning Disk Processing (SDP). The effects of synthesis parameters such as chitosan derivative concentrations, spinning disk rates, feeding rates of re! actants on the stability and particle size distributions of the magnetite nanoparticles have been studied. Our preliminary results show that particle size distributions, stability and disperbility in aqueous solution of chitosan derivative coated magnetite nanoparticles can be controlled by the choice of synthetic parameters including disk spinning speeds and reactants feeding rates. The coating enhances the stability and dispersibility of the magnetite nanoparticles in aqueous solution. Future work will focus on optimizing the synthesis conditions for preparation of stable chitosan derivative coated magnetite nanoparticles with desirable particles sizes and magnetic properties for biomedical applications.

· Mr Chuan Ming Deng, Deakin
Ph.D candidate
Textile Group Centre for Material and Fibre Innovation Geelong Technology Precinct (GTP) Deakin University, Geelong Victoria Australia 3217
Research Activities:

3-D Deformation Process of Irregular Animal Fibres " Chuanming Deng, Lijing Wang, Xungai Wang

Deakin University

The cross-section of animal fibres varies along the fibre length, and this geometrical irregularity has major implications for the mechanical properties and processing behaviour of these animal fibres. In this study, wool fibres were subjected to tensile loading using a new Single Fibre Analyzer (SIFAN) instrument. The 3D images of fibre specimens were captured during the deformation process, and the fibre diameter variations were analysed. Key words: wool, irregularity, diameter variation, 3-D image

· Mr Alec Deslandes, Flinders
Student
School of Chemistry, Physics & Earth Sciences Flinders University GPO Box 2100 Adelaide SA 5001
Research Activities:

Hydrogenation of Carbon Surfaces via Plasma Treatments" A. Deslandes, J.G. Shapter, J. S. Quinton

School of Chemistry Physic and Earth Sciences, Flinders University, Adelaide, Australia

Graphite (HOPG) has been treated with hydrogen and methane plasmas in order to hydrogenate the surface. Features caused by the plasma treatment are observed as protrusions on the surface via scanning tunnelling microscopy (STM). Etching and/or nucleation and growth features are observed, with the type of features and their distribution dependent on the precursor gas used (either hydrogen or methane) and various plasma variables. Pilot-study results using time-of-flight secondary ion mass spectrometry (ToFSIMS) give an indication of the hydrogen coverage/content of the plasma treated surfaces (observed via the hydrogen content in CxHy groups), which can be correlated with these STM effects. The effects of the plasma hydrogenation are observed to change systematically with changes in the investigated plasma treatment variables, which include exposure time, plasma pressure and applied power. These investigations will enable optimisation of plasma treatments used to prepare surfaces for carbon-based electrochemical sensors.

· Dr Trevor Finlayson, Monash
Associate Professor
School of Physics Monash University Clayton 3800 Victoria
Research Activities: Precursor and time dependent effects in association with displacive phase transitions, particularly in martensitic alloys; relaxation and microstructural studies in triglycine sulphate ferroelectrics; studies of residual stresses in engineering materials particularly using non-destructive diffraction (neutron and x-ray) techniques; microstructural and magnetic studies of Sm-Co-based magnetic alloys; structural studies in YTZ and CaSrTiO3 ceramics.

Time-resolved studies of ferroelectric materials during the application of electric fields." J.E. Daniels*, T.R. Finlayson*, J.L. Jones†, A.J. Studer‡

*School of Physics, Monash University, Clayton, Vic.3800 †University of Florida ‡Bragg Institute, Australian Nuclear Science and Engineering Organisation, Lucas Heights, N.S.W, 2234

An experimental facility to measure the time dependence of neutron Bragg peak intensities, in response to applied high-voltage electric fields has been developed at the Australian Nuclear Science and Technology Organisation. The stroboscopic technique with a timing resolution below 20?s, has been applied to the study of ferroelectric materials such as triglycine sulphate (TGS), a common pyroelectric detector material, and lead zirconate titanate (PZT), the most widely used material for electromechanical transducer applications. The results obtained show the first insight into the real-time structural response of these materials during dynamic electrical loading. Single crystal TGS shows very interesting structural behaviour in the first few hundred microseconds of switching of field intensity, which is apparent in large relaxation effects in the diffracted intensity of particular hkl reflections. In ceramic PZT we have characterised both the intrinsic (lattice strains) and extrinsic (domain wall motion) contributions to the macroscopic strain for the first time during dynamic actuation.

(Originally to have been presented by Rongping Wang who was unable to attend due to other research commitments)

· Mr Benjamin Flavel, Flinders
Student
School of Chemistry, Physics & Earth Sciences Flinders University GPO Box 2100 Adelaide SA 5001
Research Activities:

Nanosphere Lithography Using Thermal Evaporation of Gold" B.S. Flavel, J.G. Shapter, J.S. Quinton

School of Chemistry, Physics & Earth Sciences, Flinders University, Sturt Road, Bedford Park, Adelaide SA 5001

Ordered nanoparticle and patterned metal arrays on surfaces have attracted much recent attention due to their potential for far reaching application in biosensors, magnetic materials, catalysts and data storage. Nanosphere lithography, which allows the fabrication of patterned metal surfaces, is a simple, effective and unconventional technique that exploits a self-assembly process. Using this technique, polystyrene nanospheres with diameters of 100nm, 500nm, and 1μm were assembled onto a ‘muscovite’ mica substrate in a hexagonally close packed monolayer array, to provide a physical mask for material deposition. Thermal evaporation was subsequently used to deposit gold through the nanosphere mask layer, to generate a periodic array of quasi triangular gold nanostructures. Upon changing the mask to a multi-layered array of nanospheres, slightly more complex nanostructures were achieved. While nanosphere lithography is capable of producing arrays that are scalable to large areas, the technique is strongly influenced by defects in the crystalline nanosphere mask, the various types of which and their origin are investigated and discussed. Carbon nanotubes, which were chemically shortened with high carboxylic acid functionality from 3:1 concentrated sulphuric and nitric acid treatment, were immobilised onto the lithographically fabricated gold nanostructures using a surface condensation reaction. An amine terminated monolayer was assembled onto the gold array using the alkanethiol cysteamine to provide an anchor site for the nanotube.

· Mr Rajkumar Gopiraj, Monash
Undergraduate Student
School of Materials Engineering Monash University Faculty of Engineering
Research Activities: Prioritizing research in Light Alloys by using a process of 'Virtual Materials Selection' with the aid of new software and computer modelling. Instead of asking which material is best for a given set of properties, we see if new light alloys could be theoretically created and used to replace existing materials in the market-place.

Researching ‘Research’ in the Light Alloys: Can we objectively prioritize our research activities?" Rajkumar Gopiraj and Christopher R. Hutchinson§

§ARC Centre of Excellence for Design in Light Metals, Department of Materials Engineering, Monash University, Clayton, 3800, Vic. Australia

In selecting a material for a particular application, an engineer has to make a choice from ~80,000 currently available distinct materials. For an optimal choice, we should consider the competition between all materials, considering their properties, combinations of properties, economic factors, processability, etc. Software is now available to facilitate this and ‘Computed Materials Selection’ is now used by many leading engineering companies and has become a core component of the materials education at many institutions around the world. The methodology is now rather well developed but clearly it can only be applied to existing and well characterized commercially available materials. Instead of asking which material is best for a given application we may instead want to ask: If I can make a new material with properties X, Y and Z, what could it be used for? What materials could it replace? What might be the market impact? Or, what improvement in properties must I achieve in the lab to make a new material which will have a large impact in the market. In many ways, these are reverse materials selection questions and a similar methodology can be used. Here we describe our work in using a process of ‘Virtual Materials Selection’ to help prioritize and quantify those areas of materials property development that would offer the greatest competitive advantage for the light alloys (Al, Mg and Ti). Such a process may help prioritize fundamental research in these areas.

· Mr Joel Gresham, ANU
Student
Department of Engineering (Bldg 32) The Australian National University Canberra, ACT 0200 Australia
Research Activities:

Stamp Forming Fibre-Metal Laminates at Elevated Temperatures" Joel Gresham

Dept of Engineering, Australian National University

Fibre-Metal Laminates (FML) are manufactured by means of bonding alternate layers of metal and fibre-reinforced composite materials. The result is a sandwich structure with the potential to tailor the overall mechanical properties based on the properties of the constituents. Typically, manufacturing techniques used in the production of Fibre-Metal Laminates are time consuming with low volume output. Due to this, there has been limited use of FMLs in the high volume industries such as automotive. Stamp forming, a common manufacturing technique used in the automotive industry, has the potential to increase the production rate of FMLs. Current research identifies important parameters affecting the success of forming FMLs to be, preheat temperature, tooling temperature, blank-holder force, and feed rate. The main emphasis of the present study is to investigate the formability of thermo-plastic based FML systems, focusing on biaxial forming behaviour at elevated preheat temperatu! res. Measurement of real time surface strain distribution during shallow and deep drawing of laminates is used to elucidate the effects of forming at elevated temperatures. Results have shown that significant change in the strain distribution occurs at forming temperatures above the melting temperature of the adhesive. Comparison between FML and monolithic aluminium formed under identical conditions showed the FML system having a more uniform strain distribution and required less work to form. The experimental results obtained in the present study show FML systems have the potential to be adapted to the high volume production technique of stamp forming with comparable or better success than currently used materials.

· Mr Toby Hopf, UniMelb
PhD Student
MARC Group, School of Physics, University of Melbourne, Parkville, VIC 3010.
Research Activities:

Development of a Single Ion Detection System for the Shallow Implantation of Individual Donors with Nanoscale Precision" Toby Hopf, David Jamieson, Changyi Yang, Grigori Tamanyan.

Microanalytical Research Centre, School of Physics, University of Melbourne.

We have developed a technique which enables the implantation and detection of single low-energy (<15 keV) ions in a silicon substrate with nanoscale precision, and with a detection efficiency approaching 100%. The ability to configure semiconductor devices with controlled doping has a number of potential applications. For example, some solid state quantum computer architectures based on nuclear spin, electron spin or charge require precision placement of single phosphorus atoms in a silicon matrix, with registration to control electrodes allowing the quantum state of individual atoms to be manipulated and read out. Controlled doping could also overcome performance degradation in sub-100 nm scale classical devices where lack of precision in dopant placement and number leads to problems with statistical fluctuations in electrical characteristics. Our method is based upon the Ion Beam Induced Charge (IBIC) technique of nuclear analysis, commonly used with MeV light ions (Z ≤ 2), but which we have adapted to the keV heavy ion (Z > 2) regime. Collection of the ionization created in a ion strike by electrodes fabricated on the silicon wafer is used to detect the implantation of a single ion. The detection of these single sub-20 keV implanted heavy ions is challenging because of the pulse height defect involved, which arises because a substantial fraction of the kinetic energy of the incident ion is dissipated as phonons rather than ionization. Both a high efficiency electrode configuration and an extremely low detector noise level are therefore necessary in order to detect ion strike events.

· Mrs Maizlinda Idris, UNSW
PhD Student
School of Materials Science & Engineering University of New South Wales Sydney NSW 2052 Australia
Research Activities: Structural Integrity of Sandwich Composites

Contact damage behaviour on carbon fibre/closed-cell aluminium foam sandwich composites" Ms. Maizlinda Izwana Idris, Assoc. Prof. Mark Hoffman

School of Materials Science and Engineering The University of New South Wales, Sydney, NSW 2052, Australia

A sandwich composite is a combination of two stiff composite skins and a lightweight core. The function of the skin is to carry bending and in plane forces, while the role of the core is to support the skin and to carry transverse loads. The combination of skins and core offers high energy absorption and increases the flexural stiffness (EI) without significant weight penalties. As a result, sandwich composites are widely used in the civil structures and transport industries. For examples, sandwich composite panels are used in helicopter blades and shield for space applications. However, during service life, these sandwich composites may experience impact damage such as tool drops, hailstones and bird strikes. This damage has been demonstrated to significantly reduce the structural properties of the sandwich composites. Therefore, in the present research, the contact damage behaviour on the carbon fibre skin and closed-cell aluminium foam sandwich composites is investigated.

· Mr Rudy Irwan, UQ
PhD/Research Student
Room 45-118 Mansergh Shaw Mechanical Engineering Building University of Queensland Queensland 4072
Research Activities: Research on nanoindentation and nanoscratch for brittle materials

Nanoindentation of Cemented Tungsten Carbide" Rudy Irwan and Han Huang

The University of Queensland

Nanoindentation is commonly used to study mechanical properties of materials, such as hardness and elastic modulus. Recently researchers have utilized this technique to investigate material removal mechanism involved in nanogrinding. This is because an indentation process that involves interaction between a diamond tip and a work material is analogous to an individual nanogrinding event. In this work, the nanoindentation technique was used to investigate the effect of microstructure on mechanical properties, deformation and removal mechanism of cemented tungsten carbide (WC). Indentation was performed on a Hysitron Triboindenter using a Berkovich diamond indenter. Various static loads, ranging from 2 to 30 mN, were applied to examine if cracking was occurred. For each load, five indentations were made. Indentations were also made intentionally on both WC grains and binder-rich regions to examine the influence of microstructure. Surface characteristics of indentations were examined using an atomic force microscope (AFM) and a scanning electron microscope (SEM). The indentation results on cemented tungsten carbide show that both the hardness and the elastic modulus are different between grain and binder-rich regions. Crack-related events, such as pop-in and pop-out, are not evident in load-displacement curves, even though the load is increased up to 30 mN. AFM and SEM images indicate that there exist pile-ups developed near the impressions on the indented surfaces. However, no evidence of cracking can be found either, which is in agreement with the findings from the load-displacement curves.

· Dr Ruth Jarvis, ANU
Post-doc in the Laser Physics Centre, Research School of Physical Sciences and Engineering, ANU
Laser Physics Centre Institute of Advanced Studies Australian National University Canberra, ACT, 0200
Research Activities: Optical thin film deposition using ultra-fast pulsed laser deposition of chalcogenide glass; characteristion for photonics applications; and optical waveguide fabrication, including silica, polymers, inorganic polymer glass, and chalcogenide glass.

Chalcogenide glasses for magneto-optics applications" Ruth A. Jarvis, A. Zoubir, E. Gamaly, A. Prasad, A.V. Rode, B. Luther-Davies

Laser Physics Centre, Research School of Physical Sciences and Engineering, The Australian National University

Chalcogenide glasses have considerable potential for application in next generation photonic devices due to their large nonlinearities, high refractive indices and significant magneto-optic activity. We report on the optical and structural properties of laser deposited films of arsenic trisulfide and Ge-As-Se as well as the Faraday rotation of these glasses in thin film and bulk glass form across a wavelength range from 675-1550nm. As the germanium content is increased the Verdet constant is increased which we believe results from the higher refractive index.

· Mr Abdullah-Al Kafi, Deakin
Postgraduate research student
Abdullah-Al-Kafi Postgraduate Research Student Centre for Material and Fibre Innovation Deakin University Geelong Victoria 3217 Australia.
Research Activities: 1. Preparation and development of the polymer composites by using different techniques such as hand lay-up, compression moulding, UV/Gamma radiation curing. 2. Cost and wastage minimization of raw materials: Standardization of the process by optimization of raw material content. 3. Full/partial replacement of glass fiber with indigenous natural fiber jute. 4. Improvement of stabilization/pot life of unsaturated polyester resin. 5. Characterization of sustainable glass/jute-reinforced composites by FTIR, SEM, XPS etc. 6. Study of the effect of different monomer, UV/gamma radiation on the physico-mechanical properties of composites. 7. Modification of unsaturated polyester resin system by low cost swelling solvent. 8. Development of advanced natural fiber based green composites.

Effect of hybridization and resin concentrations on the mechanical properties of jute/glass fiber reinforced unsaturated polyester composites." ABDULLAH-AL-KAFI* AND BRONWYN L. FOX Centre for materials and fiber innovation, School of Engineering and Information Technology Deakin University, Geelong VIC 3217, Australia. MUBARAK A. KHAN Radiation and Polymer Chemistry Laboratory Institute of Nuclear Science and Technology Bangladesh Atomic Energy Commission PO Box 3787, Dhaka 1000, Bangladesh. M. Z. ABEDIN Department of Chemical Engineering and Polymer Science Shah Jalal University of Science and Technology Sylhet, Bangladesh.



Jute fiber (Hessian cloth) and E-glass fiber (mat) reinforced unsaturated polyester (USP) hybrid composites were prepared by compression molding technique. The composite fabrication temperature, pressure and time were 930C, 8 MT and 5 minutes respectively and 40% hybrid (Jute:glass=1:3) fibers level were maintained. To compare the mechanical properties of hybrid composites; different composites were fabricated using only jute and glass. Increased mechanical properties of hybrid composites such as tensile strength (66%), bending strength (176%), tensile modulus (86%), bending modulus (78%) was found compared to jute-based composites. For further improvement of mechanical properties and also to reduce the cost of resin, USP was properly mixed with methanol as a swelling solvent at different concentrations (25%, 50%, 75%, and 100%). It was investigated that 25% methanol in USP showed more or less same property as composites prepared with pure resin. FTIR studies were done to understand the nature of adsorbed functional groups on both jute and glass fiber surface. From FTIR analysis it can be assumed that hydroxyl groups of jute might be reacted with carbonyl group of USP. SEM analysis showed positive results such as less pull out of fibers in case of hybrid composites. *To whom correspondence should be addressed: aakaf@deakin.edu.au

· Dr Zulfiqar Khan, Deakin
Research Fellow
Center for Material and Fibre Innovation Geelong Technology Precinct Deakin University, Geelong 3217, Australia
Research Activities: Fibres and Yarns

Development of compact spun innovative products" Zulfiqar Khan

Deakin University

This work develops innovative products for a new market, using the short staple compact spinning technology. Compact spinning is achieved by the modification to the drafting process of a conventional ring spinning frame. In conventional ring spinning, twist is inserted in the drafted fibre ribbon as it emerges from the nip of the delivery rollers of the drafting zone. The twist insertion gives consolidation and strength to the forming yarn. This consolidation results in the formation of a triangle called spinning triangle where peripheral fibres of drafted ribbon are not fully incorporated into the yarn body. In compact or condensed spinning system, an extra ‘control zone’ is added to compact the ribbon of drafted but untwisted fibres. The compacting zone uses air-suction to reduce the size of the drafted fibre ribbon. As a result, fewer fibre ends poke out of the yarn surface producing less hairy and stronger yarn than equivalent ring spun yarn. The advantage of compact spinning can be realised in the reduction of up to 70% production costs than normal worsted process.

· Mr Taehyun Kim, ANU

Department of Electronic Materials Engineering Research School of Physical Sciences and Engineering Australian National University Acton ACT 0200 Australia
Research Activities: Silicon-rich oxides as functional materials for electronic, photonics and optoelectronic Nanocrystal reactions and compound formation Self assembly of nanocrystals in layered materials structure

Novel crack patterns and propagation modes in PECVD silica films – influence of film and substrate properties." Taehyun Kim, Verena Tobias, Marc Spooner, Tessica Weijers-Dall, Robert Elliman

Department of Electronic Materials Engineering, Research School of Physical Sciences and Engineering, The Australian National University, Canberra ACT 0200

Novel crack patterns, propagation modes, and crack interactions are observed in PECVD-deposited silicon-rich silica films on silicon substrates subjected to thermal annealing. Cracks form as a result of a significant increase in stress in the film, which in the temperature range 400-650°C is correlated with the loss of hydrogen from the film (up to 30 atomic-% of which is incorporated during deposition). Using ion beam techniques (including heavy ion ERD and FIB) and other complementary diagnostic techniques, we are investigating the role of the film properties (composition, hardness) on this behaviour.

· Miss Chi Li, UNSW

School of Materials Science and Engineering University of New South Wales Kensington, Sydney, NSW 2052 Australia
Research Activities:

LaNi4.25Al0.75 hydrogen storage thin film fabricated by direct current magnetron sputtering" Chi Ying Vanessa Li*, S. L. I. Chan*, Zhongmin Wang†

*School of Materials Science and Engineering, University of New South Wales, Sydney, NSW 2052, Australia †Department of Information Material Science and Engineering, Guilin University of Electronic Technology, Guilin, Guangxi, 541004, P. R. China

The electrochemical behaviour of LaNi4.25Al0.75 thin film fabricated by magnetron sputtering had been investigated. Single layer LaNi4.25Al0.75 thin films were deposited on Cu substrate by direct current magnetron sputtering with a thickness of 4.2 microns. Both scanning electron microscopy and atomic force microscopy showed that the surface of the film is relatively rough with pores of 15-40 nm in diameter as potential hydrogen storage sites. X-ray diffraction revealed that the microstructure of the layer is of fine grained crystalline and of LaNi5 type. Pressure-composition-isotherm measurement showed that the hydrogen absorption content could reach up to 1.3 wt% at room temperature and hydrogen desorption of 1.1 wt%. Its specific discharge capacity was found to be 220 mAh/g and posed itself as an excellent candidate as negative electrode in thin film battery application.

· Miss Szu Hui Lim, USyd
Research Student

Research Activities: Mechanical Testing and Microscopy Analysis

Mechanical properties of nylon 6/clay/rubber ternary nanocomposites" Szu-Hui Lim, Aravind Dasari, Gong-Tao Wang, Zhong-Zhen Yu, Yiu-Wing Mai

Centre for Advanced Materials Technology (CAMT), School of Aerospace, Mechanical and Mechatronic Engineering J07, The University of Sydney, Sydney, NSW 2006, Australia

Exfoliated nano-scale clay layers at low loadings in nylon 6 had been shown to remarkably improve the elastic modulus, tensile strength, barrier and flame retardant properties, as well as dimensional stability. This was attributed to the high aspect ratio, and homogeneous distribution of individual clay layers, providing a large interfacial contact area between the clay layers and the nylon 6 matrix. However, it was also reported that well exfoliated clay layers constrained the molecular mobility of the nylon 6 chains and suppressed the associated plastic deformation at the crack-tip, undesirably impairing the fracture toughness of nylon 6 nanocomposites and greatly limiting the applicability of these materials in load-bearing applications. Therefore, in this study, we focus on toughening of nylon/clay nanocomposites by incorporating maleic anhydride grafted polyethylene-octene copolymer (POE-g-MA) as the toughening agent in order to achieve high stiffness/strength along with high fracture toughness. Mechanical test results indicated that the ternary nanocomposites exhibited higher stiffness than the nylon 6/POE-g-MA binary blends at given POE-g-MA contents. Interestingly, the brittle-ductile transition of the nylon 6/POE-g-MA blends was not impaired in the presence of clay. TEM analysis revealed that the clay layers and elastomer particles were dispersed separately in the nylon 6 matrix. The achievement of such a microstructure depends on several parameters such as the nature of the rubber and the melt compounding conditions. The presence of fine clay layers in the matrix provided maximum reinforcement to the polymer; and at same time, its absence in the rubber particles allowed the latter to cavitate and impart toughness to the nanocomposite.

· Dr. Hua Liu, UNSW
Postdoctoral Research Fellow
School of Mechanical and Manufacturing Engineering The University of New South Wales UNSW SYDNEY NSW 2052
Research Activities: Abrasive waterjet machining for advanced material, Micro machining using abrasive waterjet

Experimental study of contouring on an alumina ceramics by using abrasive waterjet" Hua Liu

School of mechanical and manufacturing Eng. University of New South Wales

As a kind of “beam” cutting, abrasive waterjet loses its energy and begins to lag or tail behind the entrance point of the beam at the top of the workpiece. This jet tail back nature is believed to result in kerf geometric deficiencies or shape errors in contouring. Hence, the understanding of this phenomenon and associated knowledge of the effects on kerf geometrical features is essential for precision and complex cutting tasks. However, it appears that only little amount of efforts has been devoted AWJ contouring, although contouring is a more common cutting process in AWJ machining. In this paper, an experimental investigation is presented to study the various cutting performance measures in contouring of an 87% alumina ceramics by using abrasive waterjet (AWJ) over a wide range of process parameters. It finds that the taper angles on the two kerf walls are in different magnitudes in AWJ contouring. The kerf taper on the outer kerf wall increases with the arc radius (or! profile curvature), while that on the inner kerf wall decreases. Moreover, the depth of cut increases with an increase in arc radius and approaches the maximum in straight cutting for a given combination of parameters. The other process variables affect the AWJ contouring process in a way similar to that in straight cutting. The analysis has provided a guideline for the selection of process parameters in contouring of alumina ceramics using abrasive waterjet.

· Thanh Lu, UNSW


Research Activities:

High Strength Aluminum Composite used in Elevated Temperatures" Y.C. Kang, Thanh Lu and S.L.I. Chan

School of Materials Science and Engineering, University of New South Wales, Sydney NSW 2052 Australia

There is a constant challenge to increase the useful service temperature of aluminium alloys. This paper reports a study on the use of nano-particulate reinforcements to increase the useable temperature of an aluminum alloy. Different amounts of nano-SiC particulates with an average size of 50 nm were added to a 7775 matrix via powder metallurgy route. For comparison a monolithic 7775 alloy and a 7775 composite with micrometric SiC reinforcement were included. Creep tests were carried out over a range of temperatures from 673K to 773K. The creep lives of composites with nano-reinforcements were two orders higher than those of the monolithic alloy and micrometric particulate reinforced composites. The beneficial effect of nano-reinforcement was particularly significant for smaller applied loading or at lower testing temperature. Nano-particulate reinforced composites also have a threshold stress about three times that of the monolithic alloy. A logarithmic plot of minimum c! reep rate against stress leads to a high but variable stress exponent, and high apparent activation energy. Microstructural changes and precipitation coarsening during the creep test was observed under transmission electron microscope, and it was found that the extent of coarsening depended on test temperature. The nano-SiC particulates effectively pinned the grain boundaries and also interacted with dislocations within the grain, all these contribute to the superior creep resistance of the 7775 Al composites with nanometric reinforcement.

· Miss Wen Jie Ma, USyd
PhD student
AMME Building J07 The University of sydney Camperdown campus
Research Activities: Diamond like carbon coating for biomedical applications.

Effect of composition of diamond like carbon films on surface properties and biocompatibility" W.J. Ma*, A.J. Ruys*, R. Mason**, H. Zreiqat***, W.Y. Cheung****, S.P Wong****, P.J. Martin*****, A. Bendavid*****, V. J. Keast******

* Biomedical Engineering Unit/ School of Aerospace, Mechanical and Mechtronic Engineering, University of Sydney, Sydney, Australia **Department of Physiology, University of Sydney, Sydney, Australia *** Bone and biomaterial research unit, University of New South Wales, Australia **** Department of electronic Engineering, The Chinese University of Hong Kong, Hong Kong *****Industrial Physics, CSIRO, Sydney, Australia ******Electron Microscopy Unit, University of Sydney, Australia

In Diamond-Like Carbon (DLC) the sp3 fraction and the hydrogen content are the determining factors in controlling the mechanical functionality and biocompatibility. However, previous reports in this area have not adequately correlated these factors with coating optimization for specific biomedical applications. The present work is aimed at a systematic study of the structure, properties and biocompatibility of both hydrogenated and unhydrogenated DLC films produced by commercial deposition methods. Elastic recoil detection analysis (ERDA), electron energy loss spectroscopy (EELS), and X-Ray photoelectron spectroscopy (XPS) were used for structural and compositional characterization. Surface energy and surface roughness were also investigated. Human MG-63 cell after 3 days in culture showed good attachment to DLC surfaces but no significant difference in morphology on different type of DLCs. The Alkaline phosphates assay (ALP) on filtered arc deposited (FAD) DLC indicated enhanced cellular differenation than tissue culture plastic (TCP) and glass over slip. This investigation showed that DLC coating caused no adverse effects on cells in culture disregarding the chemical composition.

· Mr Michael Mansfield, Deakin
PhD Student
School of Engineering and Technology (Elgar Rd Campus) Deakin University 221 Burwood Hwy Burwood 3125 Victoria
Research Activities: Developing new lubricants for sheet metal forming

Developing a new dry film lubricant for sheet metal forming" Michael Mansfield

Deakin University

Dry Film Lubricant (DFL) technology involves replacing conventional fluid (wet) lubricants with dry products that act as both protective layers and forming lubricants. This technology will reduce the use of fluid lubricants in the press shop and has the potential to allow manufacturers to produce components from grades of steel that until now have not been used in the stamping process due to formability concerns. Forming limit trials comparing the performance of the DFL with a conventional forming lubricant on conventional forming steel grades indicate that the DFL performance is comparable to current forming lubricant technology. Draw bead simulation and corrosion (wet stack) trials on conventional forming steel grades have indicated that the DFL frictional performance is superior to conventional forming lubricants. X-ray photoelectron spectroscopy (XPS) has been used to analyse the ability of the lubricant to be removed (Removability) in laboratory trials, samples were analysed before and after several cleaning regimes to determine how much Carbon was removed from the surface of the sheet material. Surface analysis of the DFL on conventional and high strength steel grades will be conducted after each SMF stage to give an insight into the performance of the lubricant throughout the SMF process.

· Mr Ross Marceau, USyd
PhD student
Electron Microscope Unit Australian Key Centre for Microscopy and Microanalysis Australian Microscopy & Microanalysis Research Facility (AMMRF) Madsen Building F09, Room B61A The University of Sydney NSW, 2006, Australia
Research Activities: Advanced nanostructural analysis of light alloys using techniques such as atom probe tomography, transmission electron microscopy and positron annihialtion spectrocopy to derive key structure/property relationships that govern significant materials phenomena.

Vacancy-Solute Interactions During Early Rapid Hardening in Al-Cu-Mg" R.K.W. Marceau* and S.P. Ringer*, R. Ferragut†, A. Dupasquier† and M.M. Iglesias†

*Australian Key Centre for Microscopy & Microanalysis, The University of Sydney, NSW, 2006, Australia. †Dipartimento di Fisica and Centro LNESS, Politecnico di Milano, Via Anzani 52, 22100, Como CO, Italy.

This is an initial report of a multi-technique study on the effect of Mg alloying on solute-vacancy interactions during the early stages of ageing of dilute 2xxx Al-Cu-Mg alloys so as to better understand the early rapid hardening (RH) that occurs in certain compositions of these alloys and the more general phenomena of secondary hardening (SH) at ambient temperatures. Therefore, RH at 150 °C and SH at room temperature from the as-quenched condition and after 60 sec ageing at 150 °C were studied in Al-1.1Cu, Al-1.1Cu-0.2Mg and Al-1.1Cu-0.5Mg (at. %) by positron annihilation lifetime spectroscopy (PALS), coincidence Doppler broadening (CDB) spectroscopy and atom probe tomography (APT) and monitored by Vickers hardness measurements. The present results indicate that Cu-Cu, Mg-Mg and Cu-Mg clusters are formed in the ternary alloy already in the as-quenched state and that they persist during ageing at 150 °C. The fraction of the solutes Cu and Mg that were associated with vacancies after ageing was increased 10-fold and double, respectively and the strength of the Cu clustering is enhanced greatly after 60 sec at 150ºC.

· Mrs Jelena Muric-Nesic, ANU
PhD student, Dept of Engineering, ANU
Department of Engineering (Bldg 32) The Australian National University Canberra, 0200 ACT Australia
Research Activities:

Composite Materials - how to improve mechanical properties" J.Muric-Nesic, J.Campbell, P.Compston, N.Noble, Z.H.Stachurski

Dept. of Engineering, School of Engineering and Computer Science, The Australian National University, Canberra, ACT 0200

A major research direction of the ANU advanced material research group is to develop new methods of improving manufacturing processes for composite materials. This specific project is concerned with improving the quality of laminated sandwich composite structure by eliminating common defects such as voids, bubbles and poor adhesion at interfaces. Our previous research established that, from a comparison of 3 selected methods: Quickstep, Autoclave and hand lay-up, Quickstep method is superior to the other two in terms of manufacturing time and cost, and with comparable mechanical properties. In order to improve mechanical properties we are now going to experiment and analyze the effect of vibrations on composite materials. Our initial stage is to study the movement of air bubbles in a viscous liquid using Stokes law. We are approaching this in two ways: 1. setting up a SDC (Stokes Diffusion Cell) and applying fundamental laws of science. 2. assembling small laboratory for vibration experiments in order to investigate the mode of vibration, the most appropriate position for application and the ideal frequency of vibration to reduce defects to a minimum.

· Mr David Oliver, ANU
PhD Student
Department of Electronic Materials Engineering Research School of Physical Sciences and Engineering Australian National University Canberra ACT 0200 Australia
Research Activities: Nanoindentation Mechanisms of plastic deformation High-pressure phase transformations Microscopy techniques: TEM and FIB Raman microspectroscopy

Giant pop-ins in germanium under indentation" David J. Oliver*, Jodie E. Bradby*, and Jim S. Williams*, Michael V. Swain†, Paul Munroe‡

*Department of Electronic Materials Engineering, Research School of Physical Sciences and Engineering, The Australian National University, Canberra, ACT 0200, Australia †Oral Science Department, Faculty of Dentistry, University of Otago, Dunedin, New Zealand ‡Electron Microscope Unit, University of New South Wales, Sydney, NSW 2052, Australia

The deformation behaviour of germanium (Ge) under indentation is interesting both technologically and scientifically. In this study, crystalline Ge was indented with a spherical diamond tip (R=4.3 um) up to maximum loads of 50-500 mN with the UMIS-2000 nanoindentation system. Sudden excursions, or ‘pop-ins’, of unusually large magnitude (>1 µm) were observed in the force-displacement curve at higher loads. An amorphous-like structural phase was observed in residual indents following the giant pop-in with Raman spectroscopy. Samples were cross-sectioned with a focussed ion-beam microscope to examine sub-surface crack morphology. The giant pop-in was found to cause considerable material removal. Digital analysis of optical micrographs shows that large amounts of debris are found around indents with a giant pop-in. Features observed in the load-unload curve are explained in terms of the linear spring-like response of plates of material detached by lateral cracking around the indent.

· Mr Alokesh Pramanik, USyd
Postgraduate student
Dept. of Mechanical Engineering University of Sydney, NSW-2006, Australia
Research Activities:

Mechanism of tool-particle interaction during orthogonal cutting of particulate metal matrix composites" (a)A. Pramanik1,(b)L. C. Zhang1 and (c) J. A. Arsecularatne1

School of Aerospace, Mechanical and Mechatronic Engineering, University of Sydney, NSW 2006, Australia

An analytical or experimental method is unable to explore the detailed machining mechanism of a particulate metal matrix composite (MMC) due to its complexity in deformation involving the interaction among particles, tool and matrix. This paper addresses an important issue in machining MMC, the tool-particle interaction, with the aid of the finite element method. According to the geometrical orientations, the interaction between tool and reinforcements was categorized into three circumstances, i.e., particles along, above and below a cutting edge. The development of stress and strain fields in an MMC during machining was analysed in detail. Some physical phenomena such as tool wear, particle fracture, particle delimitation, particle displacements and inhomogeneous deformation of matrix material were explored and compared with the experimental results available in the literature.

· Miss Amrita Prasad, ANU
PhD Student
Laser Physics Centre, Building 54 John Carver Building Research School of Physical Sciences and Engineering The Australian National University Canberra, ACT - 0200
Research Activities: Currently working on chalcogenide glass properties and waveguide fabrication for use in optical communication network applications.

Linear and nonlinear optical properties of As-Ge-Se chalcogenide glasses" A. Prasad, C. Zha, R. Wang, D. Choi, S. Madden, A. Smith, B. Luther-Davies, M. Samoc

Laser Physics Centre, RSPhysSE, ANU

Chalcogenide glasses in the Ge-As-Se system are of interest for applications in photonics because of their high optical nonlinearity, high refractive index and relatively high glass transition temperatures. However the absorption losses of these materials are also relatively high due most likely to instrinsic phase separation that is quite common in chalcogenide glasses. Here we report on the linear and nonlinear optical properties of glasses where the Ge content has been varied. We find that whilst high Ge levels leads to high glass transition temperatures, it also generally leads to elevated optical loss.

· Mr Daniel Pyke, UniMelb

School of Physics, University of Melbourne, 3010
Research Activities: Investigation Hydrogen implanted into Silicon, crystallisation behaviour, defect formation, band structure modification, solid phase epitaxy; elastic recoil detection, Raman scattering spectroscopy, Rutherford Backscattering Spectroscopy, Time Resolved Reflectivity

Raman Spectroscopy of Hydrogen Implanted Silicon" Daniel Pyke, Dr Jeffery McCallum

University of Melbourne

Hydrogen as an implantation material into silicon has a great deal of value to the microelectronics and semiconductor industries. Via various processes, it can be used to segregate materials, generate cavities within crystalline structures and form novel structures. In many of these cases, ion implantation of the hydrogen is the most efficient and economical technique. To these and other ends, it is important to have a strong array of measurement methods to identify hydrogen related features. Some of the common methods used are Fourier transform infrared spectroscopy, multiple internal reflection plates and Positron Beam Doppler Broadening. Our investigation of ion implanted crystalline silicon using Raman spectrometry indicates a cluster of hydrogen related features in the range of wavenumbers 1900-2350 cm^{-1}. The region in which these Raman shift lines appear is in contrast with that found in measurements of hydrogenated silicon by Murakami et.al., who reported clear hydrogen related peaks at 2100 & 4150 cm^{-1}. However, it does largely agree with previous work by Stein et.al., who also found similar spectra of hydrogen features. The evolution of the Raman H-related features with low temperature anneals and in the presence of pre-formed cavity bands will be discussed.

· Dr Jamie Quinton, Flinders

School of Chemistry, Physics & Earth Sciences Flinders University GPO Box 2100 Adelaide SA 5001
Research Activities: Surface science Organosilicon coatings Thin films Surface modification

Grazing incidence X-ray studies of Lumogen Coatings for Ultra-Violet Sensing" S.J. Keough1,T.L. Hanley2, A.B. Wedding3 and J.S. Quinton1,*

1. School of Chemistry, Physics and Earth Sciences, Flinders University, GPO Box 2100 Adelaide, SA, 5001 2. Bragg Institute, Australian Nuclear Science and Technology Organisation PMB 1 Menai NSW 2234 Australia 3. School of Electrical and Information Engineering, University of South Australia, GPO Box 2471, Adelaide, SA, 5001, Australia

Coatings of Lumogen® Yellow S0790 are of interest for Ultraviolet radiation detection and have been used on the CCD cameras of the Hubble Space telescope and the Cassini space probe for UV imaging. Previous X-ray Diffraction (XRD) studies of (~100-500nm) films produced via physical vapour deposition (PVD) have revealed that a structural transition occurs upon annealing or even storing the film at room temperature [1]. In this paper, we report on X-ray Reflectometry (XRR) and Grazing Incidence X-ray Diffraction (GIXD) that were performed on 1-10nm ultra-thin Lumogen® films that were produced via physical vapour deposition (PVD) and spin-coating methods onto silicon wafer (with oxide) substrates. Our studies have shown that ultra-thin PVD films initially coat amorphously, with crystalline presence increasing with film thickness. Furthermore, the crystallinity observed in these PVD films show an identical structure to annealed PVD films of much greater thickness (~100-500nm) that have been reported earlier [1]. In contrast, ultra-thin spin-coated films, which have not been reported before, exhibit a second crystalline structure that are observed in much thicker (thermodynamically unstable) PVD films before annealing, but in the spin coated case the structure appears to remain upon annealing. Thus we have revealed two distinct equilibrium crystalline structures which are selectable by the preparation method. 1. Deslandes, A., Wedding, A.B., and Quinton, J.S., “Crystallinity In Lumogen Optical Thin Films”, Proc. 16th Biennial Australian Institute of Physics Congress, (2005), ISBN 0-9598064-8-2.

· Dr Daniel Riley, UNewcastle
ARC Fellow
School of Engineering The University of Newcastle, NSW, 2308
Research Activities: Using in-situ diffraction to optimise the synthesis of advanced materials, most notably complex ternary carbides - namely Titanium Silicon Carbide (Ti3SiC2) and related MAX Phases. These materials exhibit a unique combination of ceramic and metallic properties suitable for a wide range of applications. Current research has centred on optimising the phase purity and developing applications for these materials using a variety of techniques including, XPS, X-ray Diffraction, Neutron Diffraction and Scanning Electron Microscopy.

Using In-Situ Analysis in the Development of Advanced Materials" D.P. Riley and E.H. Kisi

The School of Engineering, The University of Newcastle, NSW

It is widely established that the synthesis process of a material can be optimised by influencing the rate limiting stages of the reaction sequence. High-flux in-situ neutron diffraction can now be used to determine these mechanisms for ultra-fast solid state reactions. The D20 diffractometer situated at the Institut Laue-Langevin (ILL), Grenoble, France, provides sufficient neutron flux to quantify the reaction sequence of solid state combustion processes with sub-second time resolution. We have recently applied in-situ neutron diffraction in investigation of self-propagating high-temperature synthesis (SHS) of a novel class of materials; Mn+1AXn Phases, where M is an early transition metal, A is a group III or IV element, and X is either C or N. This class of materials exhibits a unique combination of ceramic and metallic properties, commonly related to their layered crystal structure. Using Quantitative Phase Analysis (QPA) of diffraction data obtained during SHS of several Mn+1AXn Phases various reaction mechanisms have been revealed. Specifically, in titanium based systems such as Ti-Al-C and Ti-Si-C, the α-Ti → β-Ti transition has been identified as a “reaction trigger”, initiating a self-sustaining chemical reaction that converts reactants into the final product phase. More generally, it is anticipated that in-situ neutron diffraction will allow for wider process optimisation and aid the development of novel materials. Furthermore, with the commissioning of the OPAL research reactor these techniques will soon be available to the Australian materials community.

· Dr Sergey Rubanov, UniMelb
Research Fellow
School of Physics The University of Melbourne Victoria 3010, Australia
Research Activities: Ion implantation, nanofabrication with Focused Ion Beam, heteroepitaxy, electron microscopy

Ion beam induced amorphisation in silicon during 14 keV P+ implantation" S. Rubanov*, G. Tamanyan*, D.N. Jamieson*, J.C. McCallum*, S. Prawer*, F. Hudson†

*Centre for Quantum Computer Technology, School of Physics, University of Melbourne, Victoria 3010, Australia †Centre for Quantum Computer Technology, Schools of Physics and Electrical Engineering and Telecommunications, University of NSW, Sydney 2052, Australia

Ion implantation is one of the most important processes in Si integrated circuit technology because the implanted dopant atoms determine the electronic properties of semiconductor materials. The development of the single ion implantation techniques allows control over the number of dopant atoms by implanting ions one by one into a semiconductor wafer. Proposed silicon-based quantum computer architecture uses a single ion implantation technique to position an array of phosphorus donor atoms (qubits) beneath the surface of a semiconductor host. The spatial accuracy with which a single dopant can be implanted is mostly determined by hardware resolution. For the current generation of focused ion beam (FIB) systems, which can be used as single ion implantation instrument, this is of the order of 10 nm. However, during the ion implantation process the implanted ions collide with silicon atoms, thus changing their direction of propagation, generate lattice defects, gradually lose ! energy and finally coming to rest at some depth within the lattice. The crystalline to amorphous (c-a) phase transformation during ion implantation at high doses also attract significant attention because of the use of this technology in the semiconductor industry. In this work we employed TEM to study the ion beam induced amorphization in Si by 14 keV P+. Obtained data allowed estimating limitation of the accuracy of the placement of the individual donors with the single ion implantation technique.

· Mr Maksym Rybachuk, QUT
PhD student
Centre for Built Environment and Engineering Research Queensland University of Technology GP O 401, GPO Box 2434 Brisbane Qld 4001 Australia
Research Activities: Investigation of properties of diamond like carbon (DLC) thin films in application to opto-electronics. An open Ar:CH4 plasma source and a bimodal ion beam sputtering deposition are used to fabricate the films.

Ion beam sputtering deposition of quality diamond like carbon films" Maksym Rybachuk and John M. Bell,

Centre for Built Environment and Engineering Research, Queensland University of Technology

Diamond like carbon (DLC) films were fabricated by bombarding a graphite target with Ne, Ar and Xe ions from a Kaufmann source. The substrate was positioned at the grazing angles to incoming the ions. In this arrangement the ions simultaneously bombard the target and the growing film. Prior to the experiments the target/substrate geometry was theoretically modelled using SRIM. The optimal angles of the target and the substrate to the ion flux were found to be 30º and 10º respectively. DLC films of high quality were synthesised at ion energies of 0.8 – 1 keV. Film growth rates were significantly higher for heavier ions i.e. Xe. We developed a simple technique suitable for DLC film fabrication at temperatures below 250º C on a variety of non-conductive substrates.

· Mr Paul Saines, USyd
PhD Student
School of Chemistry Building F11 The University of Sydney Camperdown Campus New South Wales 2006
Research Activities:

A Structural Study of Lanthanide Containing Oxygen Deficient Double Perovskites" Paul J. Saines1, Margaret E. Elcombe2 and Brendan J. Kennedy1

1 School of Chemistry, The University of Sydney, New South Wales, 2006, Australia. 2 Bragg Institute, Australian Nuclear Science and Technology Organisation, Lucas Heights, New South Wales, 2234, Australia.

Oxygen deficient perovskites are of interest as electrolytes and as cathodes in solid oxide fuel cells. Increased understanding of the structures of these compounds both at room temperature and at elevated temperatures is required to achieve favourable conductivity and may enable the production of more efficient ionic conductors. While a vast body of literature on the structures of the stoichiometric perovskites of the type A2BB’O6 is available, little is known about the structures of oxygen deficient double perovskites of the type A2BB’O6-d. It is unknown how oxygen vacancies are distributed over these sites and in particular if the vacancies can order at particular sites in the lattice. The potential for ordering of oxygen vacancies on particular sites in these compounds could lead to anisotropic ionic conductivity potentially leading to the production of more efficient devices. To investigate this possibility a series of oxygen deficient double perovskites of the type Ba2LnSn1-xSbxO6-d (Ln = Nd3+ and Pr3+/4+) were synthesised. Subsequently their structures were examined using synchrotron X-ray and neutron diffraction to establish the distribution of oxygen vacancies in these structures. The structure of Ba2NdSnO5.5 was examined using a combination of synchrotron X-ray and neutron diffraction up to 800 °C to investigate the changes in the structure of this compound over the likely operating temperature range for fuel cells in which it might be incorporated. Unusual behaviour of the lattice parameters upon heating indicated the presence of water in this structure which was subsequently confirmed by thermal gravimetric analysis.

· Mr Paul Schwenn, UQ
PhD Student
Department of Physics University of Queensland Brisbane, Queensland 4072 Australia
Research Activities: Semiconductor nanocrystal/conducting polymer blends for photovoltaics

PbS Nanocrystal/conducting polymer solar cells" Paul E. Schwenn*, Andrew A.R. Watt†, Halina Rubinsztein-Dunlop, and Paul Meredith

*Soft Condensed Matter Physics Group, School of Physical Sciences, University of Queensland, Brisbane QLD 4072, Australia; Telephone: +61 (07) 3365-3463, Fax: +61 (07) 3365 1242 Email: schwenn@physics.uq.edu.au †Department of Materials: Oxford University, UK; Email: andrew.watt@materials.ox.ac.uk

Organic photovoltaics promise a number of key advantages over conventional silicon, namely: Ease of processing, low cost, physical flexibility and large area coverage. However, the solar power conversion efficiencies of pure polymer devices are poor. When nanocrystals are blended with a conducting polymer to create a bulk heterojunction structure the optical and electronic properties of both materials combine synergistically to enhance overall performance. We use a novel single pot process to fabricate the nanocomposite photovoltaic material; in which PbS nanocrystals are grown directly in a solution of the conducting polymer MEH-PPV. This study investigates the dependence of nanocrystal growth size and subsequent power conversion efficiency as a function of polymer molecular weight. It was found that a higher molecular weight polymer resulted in the formation of a broken percolation of smaller nanocrystals that act to enhance the charge separation of excitons generated at t! he low energy band edge of MEH-PPV.

· Dr. Damyanti Sharma, UniSA
Reseach Associate
Ian Wark Research Institute, University of South Australia, Mawson Lakes Campus, Mawson Lakes, Adelaide SA-5095, Australia
Research Activities: Physicochemical studies in ionic micellar systems, Preparation of 2, 3- D arrays of metallic nanoparticles in biological liquid crystalline material for sensor applications.

A single step method for the preparation of gold nanoparticles" Dr Damyanti Sharma and Prof. Roger Horn

Ian Wark Research Institute, University of South Australia

There has been a keen interest for developing a biologically friendly approach for the preparation of gold nanoparticles for their application reasons. A quick and single step method is established for the preparation of gold nanoparticles in lecithin/water systems where lecithin itself acts as a reductant. This is a step forward for developing more biologically friendly and an approach providing less toxicity to gold nanoparticles. The method involves sonication of lecithin/aq hydrogentetrachloro aurate(HAuCl4) which produces a pinkish purple color within seconds of sonication. Two methods of sonication (using a bath type sonicator and sonicator with probe) were used and it was clear that power of sonication plays a role in reducing the time of reduction of HAuCl4. The bath type sonicator takes much longer time (140-150 min) than the sonicator with probe (30-50 sec). The UV-Vis, Dynamic Light Scattering (DLS) and Transmission electron microscopy (TEM) experiments show that the of gold nanoparticles prepared this way are polydispersed and are of different shapes. The shapes varying from spherical to polyhedral and triangular, and rod shaped particles. Most of the nanoparticles are somehow attached to lecithin and some aggregating with each other. To overcome this, an anionic surfactant sodium dodecylsulfate (SDS) and tri-sodium citrate were tried for stabilization. SDS stabilized particles are well dispersed and are stable over six months. Surprisingly the SDS stabilized particles are smaller in size (from 7-20 nm) and all the particles being spherical in shape as compared to citrate stabilized or without stabilizer samples. keywords- gold nanoparticles, egg-lecithin, autoreduction, sonication, stabilization

· Dr Santosh Shrestha, UWollongong
Postdoctoral Fellow
Faculty of Engineering University of Wollongong Wollongong NSW 2522
Research Activities: Semiconductor processing and characterisation, ion implantation, ion beam analysis, thermoelectric measurements

Nitrogen Excess, Impurities and Defects in Indium Nitride Films" Santosh K Shrestha*, Heiko Timmers†

*Institute for Superconductivity and Electronic Materials and School of Engineering Physics, University of Wollongong, Wollongong NSW 2522, Australia †School of Physical, Environmental and Mathematical Sciences,University of New South Wales, Canberra ACT 2600, Australia

In recent years interest in indium nitride thin films has increased significantly. The usefulness of this material has been suggested for a wide range of applications including in optoelectronics, high frequency and high power transistors and solar cells [1]. Indium nitride film is difficult to grow due to its low dissociation temperature. Lack of native substrate is another issue for the growth. Although the quality has been improved by, for example, use of substrate nitridation and buffer layers [2-5], the presently available films tend to have unbalanced stoichiometry, impurities contamination and high degree of lattice damage. This paper reports the results from compositional and structural analysis of several types of indium nitride thin films with ion beam analysis techniques. Elastic Recoil Detection analysis with heavy ions have shown that the films tend to posses excess nitrogen so that the nitrogen-to-indium ratio is greater than unity. This was unexpected since nitrogen vacancies had widely been attributed to cause the n-type carrier concentration observed in as-grown indium nitride films. In addition, all types of films contain some degree of carbon and oxygen contamination. The lattice environment of indium nitride films has been investigated with Perturbed Angular Correlation spectroscopy using the 111In/Cd probe. This study has shown that the indium nitride films have highly defective lattices. The interaction frequency of the 111In/Cd probe in indium nitride has been determined as 28 MHz. [1] A.G. Bhuiyan, A. Hashimoto, A. Yamamoto, J. Appl. Phys. 94 (2003) 2779. [2] Tsuchiya et al., Jpn. J. Appl. Phys. 38 (1999 1884. [3] H. Lu et al., Appl. Phys. Lett. 79 (2001) 1489. [4] Y. Saito et al., Jpn. J. Appl. Phys. 40 (2001) L91. [5] M. Higashiwaki, T. Matsui 2002), Jpn. J. Appl. Phys. 41 (2002) L540.

· Mr Rajnish Singh, UNSW
PhD Student
School of Material Science and Engineering University of New South Wales Sydney,NSW-2052 AUSTRALIA
Research Activities: Nanoindentation-induced damage and modelling of diamond-like carbon coating on ductile substrates.

Indentation modelling of a multilayer graded amorphous carbon coating on a steel substrate" Rajnish K Singh*, P.J. Slack*, Z.H. Xie*, P. Munroe*, M. Hoffman*, A. Bendavidb†, P.J. Martinb†

*School of Materials Science and Engineering, University of New South Wales, Sydney,NSW-2052,Australia †CSIRO Industrial Physics, PO Box 218 Lindfield, NSW 2070, Australia

A multilayer graded amorphous carbon coating system was developed for high loading protection, based upon the following design concepts: a) a thin TMS layer (a-C:H:Si) was deposited at the interface of the coating and steel substrate as an adhesion enhancer, b) Amorphous hydrogenated Carbon (a-C:H) was deposited using Plasma assisted Chemical vapour deposition (PACVD) as intermediate layer to increase the ductility and reduce the residual stress of the coating, and c) a rigid and hard DLC top layer was prepared using filtered assisted cathodic vacuum deposition (FACVD) for contact protection. Finite element modelling was performed to understand the deformation behaviour of the coated system during spherical indentation. Specifically, the indentation load-displacement relationship and stress distribution were analysed with consideration of residual stress. The advantage of this multi-functional coating system over the single layer amorphous carbon coating was revealed in terms of crack suppression, which is consistent with the subsurface observations of indentation damage using dual ion/electron beam instrument.

· Mr Kim Siow, UniSA
Phd student
Ian Wark Research Institute, University of South Australia, Mawson Lakes Campus, Mawson Lakes SA5095 Australia
Research Activities: plasma polymerization technique for biomaterials, biomedical or pharmaceutical applications.

Functional coatings by plasma co-polymerisation" Siow KS, Kumar S, Britcher L and Griesser HJ

Ian Wark Research Institute, University of South Australia, Mawson Lakes SA5095, Australia

Plasma polymerization is an excellent means of producing ultrathin (nm to a few 100 nm) polymeric coatings with specific surface chemistries. However, for some desired chemistries it is difficult to polymerize suitable volatile compounds; in such instances it is advantageous to utilize a gas mixture comprising a hydrocarbon compound that readily forms a polymer and another volatile compound that provides desired surface functional groups. We illustrate this with dimethyl sulfoxide (DMSO), which by itself polymerizes inefficiently. In contrast, co-polymerization with octa-1,7-diene yielded good functionalized coatings. The effects of discharge power on the resulting plasma polymers were investigated by XPS. Low powers (10-20 W) provided good deposition, whereas higher power resulted in extensive fragmentation of the monomers and lower deposition. Fitting of S2p and C1s peaks showed increased formation of sulfur and carbon moieties of higher oxidation states at higher dischar! ge power, due to