|Micro and nanoscale measurement and characterisation are playing an ever increasing role in industry in accelerating development of new products. Companies of all sizes require access to both equipment and analytical expertise to be successful in this vital area of technology.
The Centre of Excellence in Metrology for Micro and Nano Technologies (CEMMNT) is a new company funded by the UK Department of Trade and Industry (DTI) and its partner organisations. It has been established to provide open access design, measurement and characterisation services and solutions to organisations commercialising new products and processes based on micro and nano technologies (MNT).
CEMMNT unites five global MNT leaders ideally positioned to supply industry: BAE Systems, Coventor, QinetiQ, the National Physical Laboratory (NPL) and Taylor Hobson. CEMMNT’s management hub is based in Loughborough at the Systems Engineering Innovation Centre (SEIC). Each partner provides complementary expertise that benefits products at different stages of their lifecycle, providing customised solutions across all industrial sectors, as illustrated by the following examples:
Applied Nanodetectors (www.applied-nanodetectors.com) is an SME with significant intellectual property in the field of nanotechnology-based sensors for environmental and medical applications. Its Managing Director, Dr Victor Higgs, approached NPL to gain open access to nano technology techniques and expertise. Dr Higgs was offered consultancy supported by the DTI’s Measurement for Innovators (MFI) scheme. This programme provided Applied Nanodetectors with firsthand experience of how the metrology of nano materials could be used to accelerate the development of new products and intellectual property. Dr Higgs utilised a range of measurement facilities including a new Atomic Force Microscope with support from Dr Alex Cuenat of NPL’s nano functional materials team. The data generated enabled applications for additional funding in collaboration with NPL, to support the further development of gas sensors. This example illustrates the benefits that the CEMMNT partnership and its open access philosophy can bring to SME’s.
High-resolution Transmission Electron Microscopy (HRTEM) is ideally suited to the analysis of multilayer thin films, semiconductor heterostructures, synthesised nanoparticles, carbon nanotubes and nano-composites giving structural information at the most detailed (e.g. lattice imaging) level. TEM provides key information relating to nanotube properties, including the number of walls, tube diameter, wall roughness and identification of co-located species such as fillers or catalyst particles.
In the catalysed growth of carbon nanotubes, Energy Dispersive X-ray spectroscopy (EDX) nano analysis of individual metal particle elemental compositions can be used to test for inter-relationships between catalyst particle size, composition and Nanotube form and diameter. CEMMNT has TEM instruments available at QinetiQ and NPL equipped with digital camera imaging systems to permit rapid response investigations and an inhouse project to develop molecular scale chemical fingerprinting by integrating electron energy loss spectroscopy (EELS).
The MEMS industry is projected to reach over $25 billion by 2009 (source: NEXUS). It is vital that SME’s with new devices can accurately design and test prototype performance. CEMMNT partners, the SEIC and Coventor provide the design tools and systems engineering knowledge to develop smart monitoring and diagnostics techniques, potentially leading to selfanalysis.
The tools will be developed to provide multi-functional modelling, simulation and prototyping design capabilities. In addition, CEMMNT offers a full range of metrology services for static and dynamic characterisation of MEMS devices. Optical profilometry under stroboscopic illumination at QinetiQ measures XYZ displacement characteristics and device resonant responses under operational conditions with sub-nanometre vertical sensitivity. Micro-imaging vibrometry at NPL determines resonant frequencies and out-of-plane displacements. Orthopaedic implants have seen a dramatic increase in demand over recent decades as the population ages.
Enhanced performance and longevity requirements drive component quality control. In total hip replacement systems, characterisation of the primary components and subsequent component wear require a range of metrology techniques. The roundness of the femoral cup which is crucial to its load bearing capability is measured using Taylor Hobson Talyrond stylus inspection systems. Accurate control of the taper on the head and stem optimises the rigidity of the implant and is measured by taking multiple circular traces to determine the cone angle. Optical profilometry offers a rapid non-contact approach to determine wear and volume of lost material on femoral heads. The nanoscale polished finish on a ceramic cup surface is shown in Figure 4.
Optical profilometry also provides non-destructive measurement of coating thickness, which is widely used in both the stents industry and for determining passivation layer thickness in microelectronic devices application examples highlight how CEMMNT’s partnership can combine its expertise and facilities to provide either standard off-the-shelf or bespoke customised solutions at each stage of product and process development for all industry sectors.