Current Vacancies

No vacancies available at the moment

Studentships

The following studentships are available and linked to, but not directly part of, the Nanorobotics programme, these studentships are available for UK citizens.

1. Development of Nanotools for TEM Nanoroboitcs
   >> Click here for more information

2. Novel Quantum Computing Device Fabrication and Testing
   >> Click here for more information

3. Nanomaterials in Action: In-situ Alloying at the Nanoscale
   >> Click here for more information

4. Wear and Degredation of MEMS Components
   >> Click here for more information

5. Novel Magnetic Nanowires: Fabrication and Characterisation
   >> Click here for more information

6. Nanofilled Composites for Medical and Dental Applications: Mechanical Failure at the Nanoscale
   >> Click here for more information

7. Thermal Stability of Direct-Write Nanostructures Deposited by Focused Ion and Electron Beams
   >> Click here for more information

8. Ion Implantation Studies in Oxide Glasses
   >> Click here for more information

9. Nanoscale Electron Tomography and Nanopatterning
   >> Click here for more information

10. 3D Chemical Mapping of Glass Nanocomposites and Nanoporous Ceramics
    >> Click here for more information

11. Bonding and Morphology of Diamond-like-Carbon Coatings and Carbon Nanoobjects
    >> Click here for more information

12. Coordination and Valence Chemistry of Cations in Oxide Glasses and Ceramics
    >> Click here for more information

[Back to Top]

Machine Vision of Magnetic Nanostructures using Nanorobotics

The Microsystems and Machine Vision Laboratory is part of the Materials and Engineering Research Institute (http://www.shu.ac.uk/research/meri/) at Sheffield Hallam University (http://www.shu.ac.uk/). We have an EPSRC studentship in the area of Machine Vision and Manipulation for Nano-engineering Systems. The post is only available for applicants from the United Kingdom (UK) or the European Union (EU).

Applicants should have a good BEng (Hons) / BSc (Hons) degree in Science, Engineering or a related discipline, with an excellent analytical background. In addition skills in the following areas will be particularly useful:

1. Good mathematical skills
2. Some background in machine vision
3. Good programming skills with possibly some experience in UNIX/Linux
4. Some practical engineering skills

For further information, informal enquiries can be made to the Project Supervisors: Dr Bala Amavasai (http://www.shu.ac.uk/mmvl/Staff%20profiles/Amavasai.html) on +44 (0) 114 225 4520 (b.p.amavasai@shu.ac.uk (mailto:b.p.amavasai@shu.ac.uk)) or Dr. Jon Travis +44 (0) 114 225 3300 (j.r.travis@shu.ac.uk (mailto:j.r.travis@shu.ac.uk)).

The following websites provide more information about the research group and project:

1. The Microsystems and Machine Vision Laboratory Homepage
2. The Nanorobotics project consortium Page

Interviews will take place within a month of the closing date. You will be required to give a 15 minute presentation on the following topic: "Recent advances in machine vision and manipulation systems in micro and nanotechnology?.

You are required to send a cover letter and CV to:
Dr. Bala Amavasai
Microsystems and Machine Vision Laboratory
Materials and Engineering Research Institute
Sheffield Hallam University
Pond Street
Sheffield S1 1WB UK

The closing date is 3 April 2006. Please also send a confirmation e-mail to the project supervisors.

[Back to Top]

Development of Nanotools for TEM Nanoroboitcs

Supervisor: Dr. B.J. Inkson (in collaboration with Nottingham University)
The development of nanorobotics (material nanomanipulation and testing under severe spatial constraints) has important implications for many areas of nanotechnology. We have developed a novel miniaturised piezo-controlled nanopositioning system which fits into an electron microscope. To this nanopositioning system, there is the possibility to fix many different types of nanotools and nanosensors to measure materials properties at the nanometre level whilst simultaneously observing with the electron microscope. This project will involve developing novel nanorobotics nanotools (functionalised tips/probes) optimised for a variety of exciting applications including (i) picking up nanoscale volumes/molecules (nanogrippers), (ii) depositing material/molecules (nanopens), (iii) generating local deformation (nanoindentation) and (iv) making local electrical measurements (nano-electrodes).

[Back to Top]

Novel Quantum Computing Device Fabrication and Testing

Supervisors: Dr. B.J. Inkson and Prof AG Cullis (in collaboration with QinetiQ, Malvern)
A revolution in nanomanipulation systems for electron microscopes is enabling unique devices to be manufactured by the nanopositioning of molecules and nanoobjects within specially designed electrode/electronic frameworks. This exciting project involves the design, fabrication and testing of novel quantum computing devices which spatially confine electrons in 1D and 2D systems. The nanoscale active components, including carbon fullerenes/ nanotubes and metallic wires, will be positioned between electrodes in-situ within electron microscopes (SEM/FIB/TEM) with real-time observation of the device fabrication process enabling

[Back to Top]

Nanomaterials in Action: In-situ Alloying at the Nanoscale

Supervisors: Dr BJ Inkson and Prof JH Harding
Understanding the physical processes by which metals interact in the solid state to form alloys are of vital importance in the development of new ultraperformance aerospace alloys and metallic components of micro- and nano-electromechanical system (MEMS and NEMS) devices. Not well understood is how the change from xbulkx to xnanoscalex systems changes the dynamics and equilibrium of metal alloying processes. This project aims to characterise, uniquely both experimentally and theoretically, the dynamical interaction and reaction of metals (initially Ti-Al and Ni-Al) at the nanoscale. Two metals will be brought into contact within an electron microscope, using a unique electron microscope nanomanipulation system built at Sheffield. The structural, chemical and electrical changes at the metal-metal nanoscale bond will be recorded on video at a scale of 1 nanometre (a millionth of a millimetre!) and the chemical reaction zone quantified by state-of the art spectroscopy/diffraction/tomography techniques. For the chosen systems the possible phases of bulk metal alloys will be calculated as a function of temperature and composition. Dynamical simulations will then be performed of the in-situ alloying process to investigate the atomic-scale mechanisms at the metal-metal interface and identify any new phases in conjunction with the experiments. The nanoscale results will be compared with the phase behaviour expected from consideration of the bulk phases.

[Back to Top]

Wear and Degredation of MEMS Components

Supervisor: Dr. B.J. Inkson (in collaboration with QinetiQ, Malvern)
Metal and ceramic wires and cantilevers smaller than a micron in size are being developed for use in micro- and nano-electromechanical system (MEMS and NEMS) devices. Surface wear and damage can be much more dangerous in such tiny components than for bulk samples. This project, with the MEMS centre at QinetiQ, Malvern, is to characterise the mechanisms of damage and wear in MEMS devices after specified fractions of projected lifetime. Damage build up from thermal/stress cycling and repeated material impact (wear at joints) will be characterised by advanced microscopy methods including real-time impact testing of nanocontacts in the TEM, site-specific FIB-TEM samples extracted from tested specimens, and 3D FIB/TEM microstructural analysis. The microstructural evolution will be linked to simple finite element modelling of the component deformation (QinetiQ), with the aim to design new damage resistant MEMS devices.

[Back to Top]

Novel Magnetic Nanowires: Fabrication and Characterisation

Supervisors: Dr BJ Inkson and Prof T Schrefl
Under carefully controlled conditions the anodic oxidation of aluminium can result in an alumina thin film containing a self-assembled array of high aspect ratio nanopores. Functional nanowires, possessing diverse and novel properties, can be fabricated by the billion in a beaker by using the xporous aluminax as a template into which vast arrays of nanowires and nanotubes are grown by electrodeposition of materials into the self-ordered pores. This project will involve the fabrication of novel magnetic nanowires by electrodeposition into porous alumina templates. The microstructure of the wires will be characterised by advanced electron microscopy, as a function of the wire width and length which can be varied by controlling the porous alumina template growth. Single nanowires will be functionally tested and assembled into prototype devices using novel in-situ TEM mechanical and electrical probes built under the Sheffield RCUK nanorobotics programme. The structure and performance of the magnetic wires will be compared to theoretical models; the interplay between the crystallographic structure and the magnetic properties will be calculated using finite element simulations. In particular the interaction of magnetic domain walls with grain boundaries will be studied.

[Back to Top]

Nanofilled Composites for Medical and Dental Applications: Mechanical Failure at the Nanoscale

Supervisors: Dr BJ Inkson and Prof P Hatton (Dentistry)
Biocompatible ceramic-polymer composites are used extensively in medicine and dentistry for human tissue repair. More recently, nanoparticles have been employed in the production of novel composites with the intention of improving their properties (e.g. wear resistance). Understanding the surface and interfacial properties of these functional materials at the nanoscale is very important for their molecular design. At Sheffield we are quantifying the nanomechanical and nanotribological properties of biocompatible ceramic-polymer nanocomposites using advanced microstructural techniques including state-of-the-art 3D tomographic analysis and wear testing inside electron microscopes. While the limited data available suggests that these nanostructured biomaterials have improved wear characteristics, the properties appear to be strongly influenced by the size, shape and distribution of the nanoparticles. The aim of this PhD programme is therefore to carry out a detailed study of the nanoscale properties and failure modes of these novel nanofilled medical and dental composite materials.

[Back to Top]

Thermal Stability of Direct-Write Nanostructures Deposited by Focused Ion and Electron Beams

Supervisor: Dr. B.J. Inkson
New direct-write technologies enable complex nanostructures to be directly written onto surfaces without the need for traditional multi-step lithographic based nanodeposition processes. One method involves the use of a highly focused beam of Ga+ ions (FIB) or electrons (SEM) to locally breakdown organic molecules on a surface ? leaving behind the desired metal or ceramic atoms only in the places the ion or electron beam have been. Because the ion or electron beam can be scanned in any pattern, nanostructures ranging from single nanoscale electrodes to large scale patterns can be written on a surface. Not much is known about the thermal stability of FIB and e-beam direct-write deposits, and this is a crucial issue for their use in the electronics industry for depositing, joining and repairing nanoscale components. This project will quantify the thermal stability of metallic and ceramic based FIB and e-beam direct-write components. Changes in microstructure after thermal cycling (morphology, crystallinity, chemistry + substrate reactions), including in-situ real-time thermal testing in electron microscopes, will be characterised by a range of state-of-the-art FIB and TEM techniques.

[Back to Top]

Ion Implantation Studies in Oxide Glasses

Supervisor: Dr G Moebus, Dr M Ojovan
High-resolution microstructure and chemical coordination of ion and electron bombarded oxide glasses are to be analysed using state-of-the art electron microscopy and spectroscopy equipment. Special emphasis is on accumulation of defects into clusters, induced phase separation, and formation of crystalline microphases in the glass matrix. The motivation for this study towards applications relates to three fields: (i) simulation of irradiation damage in radioactive glasses for actinide immobilisation. Both light element (He, C) and heavy element (e.g. Pb) implantation are used to model the alpha-decay and atom-recoil damage. (ii) Optical and electronic properties of surface near regions in such glasses become subject to design (e.g. graded index, graded absorption, microphase quantum confinement, etc.), with a prospect of many unexplored applications. (iii) Generation of arrays of functional nanoparticles (magnetic Ion-implantation studies in Oxide glasses.

[Back to Top]

Nanoscale Electron Tomography and Nanopatterning

Supervisor: Dr G Moebus
A range of PhD topics are available in the wider fields of Computed Tomography (CT) using nm-resolution electron microscopy and also nanoscale patterning by Direct Write electron beam applications, respectively combinations of both. Computed Tomography is a well established method of medical 3D imaging and reconstruction using X-ray absorption as projection mechanism. By the same principle, electron tomography (ET) can be applied by tilting a sample inside a TEM goniometer and recording projection images at many angles. With its nm-resolution, ET has enormous potential in 3D measurements of nanoobjects and devices. Typical projects will specialise in and develop particular image acquisition procedures, image generation modes of electron microscopy, and improve reconstruction software with the attempt of maximising resolution and minimizing artefacts. Application areas for students to chose from will be in the field of nanoparticles, nanoporous and nanocomposite materials, or in the structure solution for porous bionano-materials, such as photonic crystals found in butterfly wing scales (the latter in collaboration with Exeter University, Dr P Vukusic). The same electron microscopes can be used in a focused probe mode to locally illuminate and modify the structure or composition of a material with a resolution exceeding the best lithography processes available. This nanostructuring and nanopatterning by electron beams (Direct Write) combines some fundamental irradiation chemistry aspects with envisaged application for information storage, text writing, nanoscale pre-structuring of substrates, etc. Individual projects within this area can be methodology based or examine the response of a particular group of materials to sub-nm sized electron beams, such as volatile oxide glass composites, selected crystalline mineral phases or thin films of metals. High-End Instrumentation used in this range of projects comprises the 300kV High-resolution TEM in the Sorby Centre as well as the 200kV FEGTEM, Electron Energy Loss Spectrometry, and the Focused Ion Beam microscopy within the Engineering Faculty joint facilities. (Part of RCUK Basic Technology project on nanomanipulation).

[Back to Top]

3D Chemical Mapping of Glass Nanocomposites and Nanoporous Ceramics

Supervisor: Dr G. Moebus, Dr R.J. Hand
Chemical composition can now be mapped at nm-resolution by analytical TEM using imaging energy filters. The project comprises the application of this technique to the analysis of reaction/corrosion products of glasses. The complementary sensitivity of EELS (electron energy loss spectroscopy) will be used to detect distribution of elements non accessible by EDX (energy dispersive X-ray spectroscopy). For heavier elements, a comparison with STEM-EDX mapping is planned. As a further challenge the extension of both EELS and EDX chemical mapping techniques to 3D will be explored using new specimen preparation techniques which allow high-tilt observation of samples on the JEOL 2010F-FEGTEM. Amongst the application areas for glass-nanocomposites and nanoporous glasses are functional optical and nanomagnetic materials and also the immobilisation of cations (to simulate radionuclide storage and disposal) (This research is part of ISL, Immobilisation Science Laboratory).

[Back to Top]

Bonding and Morphology of Diamond-like-Carbon Coatings and Carbon Nanoobjects

Supervisor: Dr G. Moebus, Dr M. I. Ojovan, Dr R .J. Hand
Diamond like carbon is an industrially relevant modification of amorphous carbon comprising a high percentage of sp3-hybridized structural units (resembling crystalline diamond). It shows improved hardness and durability as a coating, both mechanically and chemically. Using electron energy loss spectroscopy (EELS) the chemical bond distribution and the homogeneity of an industrial coating, deposited on silicon will be assessed (in collaboration with Teer Coatings Ltd.). The same methodology of high spatial resolution EELS will be applied to map the bond distribution in carbon nanoobjects such as nanotubes or nanodeposites.

[Back to Top]

Coordination and Valence Chemistry of Cations in Oxide Glasses and Ceramics

Supervisors: M I Ojovan, R J Hand
The knowledge of the structural units, coordination numbers, and bond types constitutes an essential part of the structural solution of complex oxide glasses and ceramics. An important tool to assess such parameters is the fine structure in spectra of Electron Energy Losses in the electron microscope. Unlike with most other spectroscopies, the TEM provides measurements with high spatial resolution and can also observe dynamical changes whether due to irradiation or temperature changes. Furthermore fine details in such spectra can be correlated to the oxidation state of structural cations or doping atoms in such phases. A choice of individual groups of materials is available ranging from radionuclide immobilisation over functional optical glasses to titanate ceramics. (This research is part of ISL, Immobilisation Science Laboratory).

[Back to Top]