- Email: [email protected]
Smart Materials Bulletin
ISSN 1471-3918 November 2000
Layered ultrathin polymer films can be erased by external stimuli Scientists at the University of Illinois at Urbana-Champaign in the US have fabricated ultrathin organic films that can be stacked together and 'erased' by external stimuli that cause a build-up of electrostatic charge in any ionisable species within the layers. The erasable polymer multilayers could have applications in many diverse fields, including biosensors, nonlinear optical devices and selectively permeable membranes. 'We specifically designed this material so that when it is placed in the desired environment, it would readily dissolve and release embedded agents such as drugs,' said Steve Granick, a professor of materials science at UIUC and a researcher at its Frederick Seitz Materials Research Laboratory. 'We can control the durability of the material through the application of external stimuli.'
To make their erasable material, Granick and postdoctoral research associate Svetlana Sukhishvili built up, layer by layer, very thin films of alternating polymeric acids and bases on a .germanium crystal. The films could also be deposited on other materials, such as glass, mica or Teflon. Foreign compounds can be added to the layers as they are formed. 'By adding additional layers, we not only increase the amount of the embedded compound, we also make the material more stable, robust and resistant to attack in unwanted environments,' Granick said. Assembly of the films is guided by hydrogen bonding. 'One unique aspect of the assembly process is reversibility,' Granick said. 'The resulting multilayers can be selectively destroyed after they are created.' The controlled destruction of the material can be initiated by a change in pH, or
the application of an external electric field or a change in the surrounding salt concentration, both of which cause the material's ionic bonds to break. For example, an electronic sensor could be made to immediately release an embedded agent by applying an electric field and dissolving the material. Although this particular work is still a long way from practical application, the concept could eventually be used for the controlled release of agents embedded within the polymeric material. The researchers demonstrated the principle by embedding molecules of the dye Rhodamine 6G in the multilayer films and then releasing them by erasing the films through appropriate stimuli. The work on these erasable polymer films was described in the 4 October issue of the Journal of the American ChemicalSociety.
Project to develop new materials for 'spintronics' The University at Buffalo, New York is leading a US$10 million project to develop specific ferromagnetic materials for use in 'spintronics', an emerging research field focused on spin-dependent phenomena applied to electronic devices. The promise of spintronics is based on manipulation of the spin as well as the charge of electrons, to enable them to perform new functions. The management of electron spin should lead to the development of remarkable improvements in photonics, data processing and communications technology. However, this will require the development of radically new materials and technologies, specifically magnetic semiconductors and structures that permit manipulation of the electron spin direction. The DARPA project involves seven interdisciplinary teams at nine institutions. The effort will be directed and coordinated by UB's Center for Advanced Photonic & Electronic
Materials, and also involves the University of Notre Dame and Indiana University, the University of Wtirzburg in Germany, the University of Texas at Austin, the US Naval Research Laboratory, North Carolina State University, Vanderbilt University and Worcester Polytechnic Institute. If spin can be manipulated, electrons could perform new functions in data processing and storage within the same basic component. This would make possible 'quantum computers' that could encode information in an infinite number of spin states, not just in binary form. To align or otherwise manipulate the spin orientation, metals or semiconductors must be developed that can sense electron spin direction and create electron gateways. The project will develop ferromagnetic heterostructures such as In(Mn)As/Ga(Mn)Sb/AI(Mn)Sb and novel devices, to produce and detect infrared and farinfrared signals.
Contents News
1
Health monitoring of UCSD's I-S/Gilman Advanced Technology Bridge 6 Use of adhesives in manufacturing adaptronic microsystems for lightweight structures 11 Research Trends Patents Events Calendar
ISSN 1471-3918/00/$20.00 @ 2000 Elsevier Science Ltd. All rights reserved This journal andthe individual contributions contained in it areprotected under copyright byElsevier Science Ltd,andthefollowing terms andconditions apply to theiruse:
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Stretching and contracting molecules A new molecular device devised by Jean-Pierre Sauvage and colleagues at the Universite Louis Pasteur in Strasbourg, France works in a similar way to real muscle. Work reported in the 15 September issue of Angewandte Chemie International Edition describes an assembly of two molecules capable ofstretching and contracting when prompted by chemical signals - a 'molecular muscle'. Muscle cells are long, thin tubes divided into segments, each containing filamentary molecules that interpenetrate each other, To contract muscle, the tips of one filament type stick to the other's strands and pull themselves along to cause deeper interpenetration. The French team has devised twinned strands that can jump along one another to increase or decrease their combined length. This malces them like a muscle pair, except that in this case the two molecules are identical; and each molecule ends in a loop through which the tail of the other is threaded. Such structures are called rotaxanes, but these new rotaxanes are unusual because each of the paired molecules in the assembly acts as both hoop and thread, The researchers estimate that each 'contraction' shortens the rotaxane by about 27%, which is about the same as the maximum shortening in contracted muscle.
For more information, contact: Professor Jean-Pierre Sauvage, universlte Louis Pasteur, InstitutLe Bel, 4 rue Blaise Pascal, F-67070 Strasbourg Cedex, France. Tel: +33 3 8841 6130, Fax: +33 3 8860 7312, Email: [email protected]
C-MAC Industries to acquire Kavlico
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Printed by Mayfield Press (Oxford) limited
(3) Smart Materials Bulletin
Montreal-based C-MAC Industries Inc, a leading designer and
manufacturer of fully integrated electronic systems and engineering solutions, has reached an agreement to acquire Kavlico Corporation, subject to regnlatory approval. Kavlico Corporation, with manufacturing operations In Moorpark, California and Minden, Germany is the largest independent supplier of precision sensors worldwide. It employs more than 220 research, development and engineering personnel, and holds numerous patents. Kavlico has established itself as a leading technology-driven manufacturer of precision measurement and control devices and systems in MEMS, ceramic capacitive, silicon piezoresistive and electromechanical technologies, 'We are very enthusiastic joining forces with C-MAC,' said Michael Gibson, president of Kavlico. 'CMAC gives us a global platform for growth while significantly expanding our product, technology base and service offering. This will enable Kavlico to deliver increasingly value-added solutions to our customers.'
For more information, contact: Kavlico Corporation, 14501 Los Angeles Avenue, Moorpark, CA 93021, USA. Tel: +1 805 523 2000, Fax: +1 805 523 7125.
Soundproofing drowns out deep . norse In a new soundproofing method reported by a team at the Hong Kong University of Science & Technology in the 8 September issue of Science, a material made of tiny, vibrating spheres pulses copies of a sound back towards its origin, and can block noise that passes through current soundproofing. The lab demo may be developed into thin, silencing sheets for residential use, while another application might protect buildings from seismic shocks.
Current soundproofing does not work well at low frequencies, because the longer wavelengths pass relatively unimpeded through the thickness of the material. About five times as much padding is needed to shield a 200 Hz sound as effectively as a 1 kHz sound. The team, led by physicist Ping Sheng, coated 1 em-diameter lead spheres with a thin layer of silicone rubber, then encased them in a hard matrix of epoxy. The spheres vibrate inside the soft silicone as though they were suspended by springs. When a sound with a frequency close to the spheres' resonant frequency enters the material, the spheres vibrate in their soft silicone sheaths, sending out sound waves in all directions. Some of those waves interfere with the forward movement of the offending noise, attenuating it. In testing of the material, the researchers could attenuate sound by 20 dB at both 400 Hz, the resonance ftequency of the spheres, and at 1.4 kHz, the resonant frequency of the silicone layer. By adjusting the materials, they could reduce noise at other frequencies. By stacking layers of differently tuned spheres, it should be possible to soundproof the entire sound spectrum,
For more information, contact: Professor Ping Sheng, Department of Physics, Hong Kong University of Science & Technology, Clear Water Bay, Kowloon, Hong Kong. Tel: +8522358 7506, Fax: +8522358 1652, Email: [email protected]
Project to study magnetic effect alloys A group of materials with an enhanced ability to cool and heat in response to changes in magnetic fields could have applications that extend far beyond temperature regulation. The materials, discovered at the US Department of Energy's Ames Laboratory in Iowa, could be used in versatile sensors to detect
November 2000
NEWS changes in magnetic field, temperature and pressure, and may be useful in energyconversion devices. Ames Laboratory is embarking on a four-year, DOE-funded project worth up to US$4 million, to gain a better fundamental understanding of the materials and why they respond so dramatically to changes in temperature and magnetic field. A team of metallurgists, physicists and chemists will explore the properties of the Gd-Si-Ge alloys and several closely related materials. The team will also develop theories and models that detail the relationship between the composition, structure and properties of the alloys, which could then be engineered for specific applications. In 1997 Ames Lab scientists Vitalij K. Pecharsky and Karl Gschneidner Jr. reported that the Gd-Si-Ge alloys possessed a giant magnetocaloric effect, such that the materials heated when magnetised and cooled when removed from a magnetic field. Subsequent work has discovered that the materials also possess giant magnetoresistance and colossal magnetostriction. Thus a relatively small change in the magnetic field surrounding the material produces a very large change in its temperature, dimensions and electrical resistance. This makes the alloys potentially useful in energy-conversion devices, such as systems that transform magnetic energy into mechanical energy and vice versa, or in sensors. The Gd-Si-Ge alloys can also be tailored to respond across a range of temperatures.
For more information, contact: Professor Karl Gschneidner Jr., Metallurgy & Ceramics, Ames Laboratory, 255 Spedding, Ames, IA50011-3020, USA. Tel: +15152947931, Fax: +15152949579, Email: [email protected]
Polymer patterns as glue in biochips Engineers at Purdue University in Indiana, USA have developed a
November 2000
technique to glue cells or DNA to the surfaces of computer 'biochips', a technology aimed at making diagnostic devices to be implanted in the body or used for rapid analysis of food and laboratory samples. It involves the preparation of micropatterned structures from thin films prepared by block copolymerisation of monomers using UV free-radical polymerisations. The microfabrication technique is used to fashion 'micropatrerns' out of a material made primarily
materials; to instantly analyse food products for contamination; and in future implantable medical devices
from a polymer, polyethylene glycol (PEG). Purdue engineers had already made the first protein biochips, in which a protein mated to a silicon chip might be used to detect chemicals, microbes and disease. The polymer micropatterning development represents a possible means of gluing these proteins, cells or DNA to a computer chip. The work was done primarily by doctoral research student Jennifer Ward, who presented her work in July at SPIE's 45th Annual Meeting in San Diego, California. 'The patterns' smallest features were 5 urn, which makes them as small as some cells,' says Rashid Bashir, an assistant professor of electrical and computer engineering at Purdue. 'This polymer layer could be the intermediate layer between the biological entities and the chip. The protein would go on top of the polymer.' The technique could be used to form precise polymer patterns containing certain regions that attract water and others that repel water. Specific cells or molecules could be encouraged to stick to the polymer. Then, the glued biological materials on a biochip's surface would precisely fit specific cells, molecules and strands of DNA in a
Selective detection of . . uranium Ions
sample being analysed. When a targeted substance passed by the chip, it would attach to the surface and the chip would signal that it had been detected. This could be used in the laboratory for rapid chemical and genetic screening of blood and other biological
that continuously monitor glucose in a diabetic's blood and then automatically administer insulin.
For more information, contact: Dr Rashid Bashir, School of Electrical & Computer Engineering, Purdue University, 1285 Electrical Engineering Building, West Lafayette, IN 479071285, USA. Tel: +1 765 4966229, Fax: +1 7654946441, Email: [email protected]
A device for the low-cost, portable selective detection of uranium(Vl) ions has been developed by scientists in the US. The analytical microchip is based on capillary electrophoresis and a calixarene molecular recognition host, and could enable environmental scientists to make rapid assessments of the contamination of groundwater and structural materials at decommissioned nuclear power plants and other installations. The highly portable glass microchip has the advantage of giving short analysis times, minimal sample consumption and waste generation. In the work, published in the 27 September Issue of Chemical Communications, Greg Collins and John Callahan of the Naval Research Laboratory In Washington, DC, working with Qin Lu of GeoCenters Inc in Rockville, Maryland report on the integration of a modified 4-sulfonic calix [6]arene, which selectively recognises uranium(VI) ions in the presence of other non-radioactive heavy metals, into a glass microchip. This calixarene has extremely high affinity and selectivity for uranium(VI). The modified molecule has a longwavelength, fluorescent tag that enables complexed UOl+ ions to
In Brief Chemistry Nobel prize for conductive polymers This year' obel Prize in Chemistry has been awarded jointly to Alan J. Heeger of the University of alifornia at anra Barbara. Alan G. MacDiarmid at the University of Pennsylvania in and Hideki Philadelphia. hirakawa of the University of Tsukuba in Japan. for the discovery and development of conductive polymers. The three mad their seminal findings in rhe late 1970s. and conductive polymers have subsequently developed inro a field of great importance. with significanr practical applications. Research on conductive polymers i also closely related 10 current rapid progress in molecular electronics. The prize, worth Kr9 million (U 930,000), will be shared equally among the Laureates.
Sensa acquires York Sensors In the UK . ensa Ltd has acquired York Sensors Lrd, which developed fibre-optic distributed rem perature sensing. The technique is now used extensively 10 monitor power distribution cables, detect leaks and monitor hot spots in refining. L G operations and petrochemicals as well as for downhole sensing in oil & gas production. The acquisition opens up new applications for ensa's technologies ro refining and delivery of electricity.
Standard MEMS facility randard MEMS Inc is to build a MO -8 inch wafer manufacturing facility for MEM and inregrared discrer semiconductor in lrzeho • Germany in a joinr venture with Philips miconductors, part of Royal Philips Electronics. The facility will also conduct R&D on new MEM product in close collaboration with the nearby Fraunhofer Institute for ilicon Technology (I IT). as well as other European research institutes. The new facility will produce sensors, medical devices and telecom components for the European and other markets.
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NEWS be easily monitored on the microchip. The device was tested for its ability to detect VO/+ ions in the presence of six competing metal ions. Each metal ion was added to a test sample solution at a concentration of 10 mg/I. Introducing any of the six impurity metal ions to the recognition host in the absence of VO/+ had no effect on the electropherogram recorded for the host. However, when VO/+ was added an additional peak was observed, which indicates that the molecule could strongly complex VO/+ ions, even III the presence of impurities. For more information, contact: Dr Greg E. Collins, Chemistry Division, Naval Research Laboratory Washington, DC 20375, USA. Tel: +1 202 4043337, Email: [email protected]
Reducing residual stress in piezoelectric . ceramics Researchers at the University of Illinois have found a way to significantly enhance the performance of a piezoelectric ceramic film, by applying a mechanical bending stress to offset the effects of residual stress in the film. 'Understanding the effects of residual stress in piezoelectric ceramic thin films is critical for their design and optimisation as smart materials,' says Nancy Sottos, a professor of theoretical and applied mechanics at VIVe. 'Not only can we greatly improve their performance as tiny sensors and III microelectroactuators mechanical (MEMS) devices, we can also put the effects of residual stress to work in a unique patterning process to better incorporate these materials on electronic chips.' Significant stresses build up in piezoelectric thin-film structures during fabrication. Intrinsic stresses
8) Smart Materials Bulletin
are caused by shrinkage and densification during drying and firing, and extrinsic stresses are induced on cooling due to the mismatch between the film and substrate thermoelastic properties. The residual stress increasingly affects the piezoelectric properties as films become thinner, 'It is difficult to selectively etch a ceramic, so standard subtractive chip processing techniques won't work well for some smart materials,' Sottos said. 'But, methods to first pattern a substrate with a special polymeric monolayer and then lay down the ceramic film have recently been developed at Illinois. The film will adhere to the exposed substrate, but not to the monolayer. Residual stress induced in the film during drying will cause it to crack off the monolayer with extremely clean edges.' For more information, contact: Professor Nancy R. Sottos, Department of Theoretical & Applied Mechanics, University of Illinois at UrbanaChampaign, 216Talbot Laboratory, MC262, 104South Wright Street, Urbana, IL 61801, USA. Tel: +1 2173331041, Fax: +1 217244 5707, Email: [email protected]
EU invests in material technologies More than 400 million (US$470 million) has been dedicated to research into new materials and associated technologies under the European Union's current research budget. Half of this money is already allocated, while the remaining 200 million will be spent on projects in key areas including nanoscale research, surface technologies, and functional materials such as biomaterials and optoelectronics. Innovative research and production technologies represent one of the mainstream activities of the 'Growth' programme, to support European industrial competitiveness and its sustainable development. This programme
reptesents nearly 20% of the entire EU research commitment under the Fifth Framework R&D Programme (I 998-2002). The Growth programme aims to encourage a multidisciplinary, panEuropean approach. Half of the project proposals come from companies, with half of these from small and medium-sized enterprises (SMEs). Through measures for and networking, clustering coordination of activities, Growth provides bridges between the academic and business communities in an effort to produce sustainable research solutions that will foster European economic growth. This call is open for proposals until April 2002, while a new call for project proposals to the Growth programme and a new evaluation procedure will be published by the EC before the end of 2000. For more information, contact: Growth Programme, DG XII, European Commission, Rue dela Loi 200, M075, B-1 049Brussels, Belgium. Tel: +32 2 295 2345, Fax: +32 2 2966757, Email: [email protected], http://www.cordis.lu/growth
Sandia spin-off to commercialise microsystems Sandia National Laboratories in Albuquerque, New Mexico has spun off a private company, MEMX Inc, to commercialise its microsystems technology. The new company will initially focus on producing optical switches for the telecoms industry using SUMMiT V, an advanced fivelevel polysilicon surface micromachining MEMS technology claimed to produce more reliable and complex devices. Sandia, a US Department of Energy national laboratory, is a leader in microelectromechanical systems (MEMS) and microsystems technologies. David Williams, director of Sandia's Microsystems Science, Technology &
Components Center, says MEMX will be the cornerstone of the new microsystems industry that Sandia and others are striving to create. of any 'Commercialisation emerging disruptive technology is a challenge,' he says. 'We believe that small and entrepreneurial companies are key to getting the into widespread technology applications. MEMX will play a critical role in achieving this objective.' 'Optical switching applications are a driving force in the MEMS arena right now,' says Paul McWhorter, one of the company founders. MEMX has licensed Sandia's unique intellectual property, and plans to advance the technology aggressively. It will use manufacturing facilities at Sandia's Microelectronics Development Laboratory to produce its first prototype, but plans to quickly build its own device fabrication facility. For more information, contact: W. David Williams, Microsystems Science, Technology & Components Center, Sandia National Laboratories, Albuquerque, NM87185, USA. Tel: +1 505844 7659, Email: [email protected] Or contact: MEMX Inc, 5600 Wyoming Boulevard NE, Suite 160, Albuquerque, NM87109, USA. Tel: +1 5058581062, Fax: +1 505 858 0935, Email: [email protected]
Sandwich organic LEOs Researchers at Queen Mary & Westfield College in London and the University of Surrey have worked out how to directly integrate optical information technology with silicon circuits. Their approach, reported in Applied Physics Letters, is to find an electroluminescent material that will sit on the silicon surface, in this case using a sandwich of two organic materials. In optical fibre communications, the signals are electronically encoded and decoded by silicon
November 2000
NEWS microprocessors, which makes for an unwieldy interface. Optical signals are created by miniaturised light-emitting diodes and lasers made from semiconducting materials, which exhibit electroluminescence when an electric current is passed through them. However, silicon is difficult to electroluminesce, and so other semiconductors are used, normally alloys of gallium, indium and arsenic. The problem with these III -V materials is that the distance between the atoms of the III-V crystals differs from the distance between Si atoms on the wafer surface, and so III- V LEDs are awkward to attach to silicon circuits. If these devices could be made from silicon, the mismatch would not occur, but normal crystalline silicon is a very poor light emitter. A team led by QMW's William Gillin has now suggested an electroluminescent sandwich of two organic materials that will sit comfortably on a silicon surface. The first layer (N, N'-diphenylN,N' -bis(3-methyl)-I, i' -biphenyl4,4'-diamine) is a mediator, and carries the electric current from the silicon to the light-emitting top layer, erbium tris(8hydroxyquinoline). This electroluminescent layer consists of organic molecules wrapped around atoms of erbium, which emit infrared light at the standard telecoms wavelength of 1.5 pm. A top aluminium layer connects to the LED. The group admits that this 'organic LED' (OLED) is still very much a prototype. It requires a very high driving voltage of 33 V, and 99.99% of the electrical energy is not converted to light. Nevertheless, the team is confident that it can resolve these problems, in view of other groups' work with OLEDs on non-silicon surfaces that turn on at only 2.5 V. For more information, contact: Dr William Gillin, Department of Physics, Queen Mary & Westfield College, Mile End Road, London E1 4NS, UK. Tel: +44 207882 5524, Fax: +44 20 8981 9465, Email: [email protected]
November 2000
Ansys, Memscap in strategic OEM agreement Pennsylvania-based Ansys, a leader in advanced CAE software, has signed a long-term business and technology agreement with Memscap in California, a leading provider of commercial MEMS design technology, to offer a unified development environment for design and analysis of MEMS-based products. The new development environment from Mernscap, which includes an integrated Ansys/Multiphysics TM, is called MEMS Xplorer (for Unix) and MEMS Pro (for PCs), and supports Cadence Design Systems, Mentor Graphics and Tanner EDA tools. The new integrated environment allows engineers to seamlessly pass data between Memscap and Ansys® tools, leading to a reduction in development time. Memscap will become a primary worldwide sales and support channel for the integrated environment in the burgeoning optical and wireless telecoms markets. This will also complement existing MEMS markets including automotive and information technology, together with future technologies such as in the life sciences industry. For more information, contact: Memscap Inc, 180 Grand Avenue, Oakland, CA 94612, USA. Tel: +1510 4445269, Fax: +15104445287. Or contact: Ansys Inc, Southpointe, 275Technology Drive, Canonsburg, PA 15317,USA. Tel: +1 7247463304, Fax: +1 7245149494.
Wireless integrated microsystems The University of Michigan is to establish the first Engineering Research Center for Wireless Integrated MicroSystems
(ERCIWIMS) in the US, under a designation by the National Science Foundation. The Center will focus on developing miniature, low-cost integrated microsystems that gather information from their environment, interpret the data received, and communicate with a host system over bidirectional wireless links. The ERC/WIMS will be led by Professor Kensall D. Wise of the UM College of Engineering, with researchers involved from most engineering disciplines as well as computer science, chemistry, public health and medicine. First-year funding from the NSF IS US$2.5 million, with an additional $2+ million In contributions from a group of global corporations and partner universities. Funding over the 11year term of the ERC is anticipated to exceed $60 million. The integrated microsystems will combine a power source, software, an embedded microcontroller, a hardwired or wireless interface to the external world, and front-end microinstruments for the intended application in a single device roughly the size of a sugar cube. UM was selected for ERC status and funding based on its impressive track record in developing MEMS with wireless capabilities. Current interdisciplinary MEMS research projects at the College include work on implantable neural prostheses, a DNA-analysis lab on a microchip, and wearable environmental monitoring devices. Applications already under development at the university include neural probes, implantable drug-delivery systems, instant blood analysis, inertial sensors (accelerometers and gyros), biomedical stimulators, miniature flying machines, and resonators for cellular phones. For more information, contact: Professor Kensall D. Wise, Electrical Engineering & Computer Science, University of Michigan, 1301 Beal Avenue, Ann Arbor, MI481 09-2122, USA. Tel: +1 7347643346, Fax: +1 734 763 9324,Email: [email protected]
In Brief Continuum in seed financing ontinuum Control Corp., a leading provider of integrated piezoelectric power systems, has closed its first round of financing 10 raise U I million, led by the Massachusetts Technology Development orporarion, Continuum requires additional capital to expand its product development and marketing. to identify. prioritise and pursue opportunities to int grate its il'ower" technology into other products. Motorola awarded key DNA detection patents Clinical Micro ensors (CM ), a division of Motorola Inc, has received five strategically important U patellts covering novel bioelectronic detection technologies. Its e ensor™ system consists of disposable biochip cartridges. propri tary software and electronic readers, and is well suited to userfriendly. rapid and cost-effective D A tests in a wide range of markets. The patellts cover methods and compositions for detecting nucleic acids, including modifying electrodes with electronically linked oligonucleotides. and m thods and compositions for bioelectronic detection employing cycling probes. The system employs small D A biochips containing electronically active electrodes coated with specific D A probes. As these probes on the chip's surface capture specific target D A present in the sample. unique and characteristic electrical ignals are generated. Kymata acquires TMP UK-based Kymara Ltd has acquired Total Micro Products (TMP) in Enschede, The etherlands for an undisclosed amount. The acquisition will create new opportunities for Kyrnara to supply products based on MEM technology. TMP is a MEM facility providing design, fast-track prototyping manufacturing services in optoelectronics and industrial instrumentation.
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Layered ultrathin polymer films can be erased by external stimuli Scientists at the University of Illinois at Urbana-Champaign in the US have fabricated ultrathin organic films that can be stacked together and 'erased' by external stimuli that cause a build-up of electrostatic charge in any ionisable species within the layers. The erasable polymer multilayers could have applications in many diverse fields, including biosensors, nonlinear optical devices and selectively permeable membranes. 'We specifically designed this material so that when it is placed in the desired environment, it would readily dissolve and release embedded agents such as drugs,' said Steve Granick, a professor of materials science at UIUC and a researcher at its Frederick Seitz Materials Research Laboratory. 'We can control the durability of the material through the application of external stimuli.'
To make their erasable material, Granick and postdoctoral research associate Svetlana Sukhishvili built up, layer by layer, very thin films of alternating polymeric acids and bases on a .germanium crystal. The films could also be deposited on other materials, such as glass, mica or Teflon. Foreign compounds can be added to the layers as they are formed. 'By adding additional layers, we not only increase the amount of the embedded compound, we also make the material more stable, robust and resistant to attack in unwanted environments,' Granick said. Assembly of the films is guided by hydrogen bonding. 'One unique aspect of the assembly process is reversibility,' Granick said. 'The resulting multilayers can be selectively destroyed after they are created.' The controlled destruction of the material can be initiated by a change in pH, or
the application of an external electric field or a change in the surrounding salt concentration, both of which cause the material's ionic bonds to break. For example, an electronic sensor could be made to immediately release an embedded agent by applying an electric field and dissolving the material. Although this particular work is still a long way from practical application, the concept could eventually be used for the controlled release of agents embedded within the polymeric material. The researchers demonstrated the principle by embedding molecules of the dye Rhodamine 6G in the multilayer films and then releasing them by erasing the films through appropriate stimuli. The work on these erasable polymer films was described in the 4 October issue of the Journal of the American ChemicalSociety.
Project to develop new materials for 'spintronics' The University at Buffalo, New York is leading a US$10 million project to develop specific ferromagnetic materials for use in 'spintronics', an emerging research field focused on spin-dependent phenomena applied to electronic devices. The promise of spintronics is based on manipulation of the spin as well as the charge of electrons, to enable them to perform new functions. The management of electron spin should lead to the development of remarkable improvements in photonics, data processing and communications technology. However, this will require the development of radically new materials and technologies, specifically magnetic semiconductors and structures that permit manipulation of the electron spin direction. The DARPA project involves seven interdisciplinary teams at nine institutions. The effort will be directed and coordinated by UB's Center for Advanced Photonic & Electronic
Materials, and also involves the University of Notre Dame and Indiana University, the University of Wtirzburg in Germany, the University of Texas at Austin, the US Naval Research Laboratory, North Carolina State University, Vanderbilt University and Worcester Polytechnic Institute. If spin can be manipulated, electrons could perform new functions in data processing and storage within the same basic component. This would make possible 'quantum computers' that could encode information in an infinite number of spin states, not just in binary form. To align or otherwise manipulate the spin orientation, metals or semiconductors must be developed that can sense electron spin direction and create electron gateways. The project will develop ferromagnetic heterostructures such as In(Mn)As/Ga(Mn)Sb/AI(Mn)Sb and novel devices, to produce and detect infrared and farinfrared signals.
Contents News
1
Health monitoring of UCSD's I-S/Gilman Advanced Technology Bridge 6 Use of adhesives in manufacturing adaptronic microsystems for lightweight structures 11 Research Trends Patents Events Calendar
ISSN 1471-3918/00/$20.00 @ 2000 Elsevier Science Ltd. All rights reserved This journal andthe individual contributions contained in it areprotected under copyright byElsevier Science Ltd,andthefollowing terms andconditions apply to theiruse:
Photocopying Single photocopies of single articles may be made for personal use asallowed by national copyright laws. Permission of the publisher andpayment of a feeis required for all otherphotocopying, including multiple or systematic copying, copying for advertising or promotional purposes, resale, and all forms of document delivery. Special rates are available for educational institutions thatwishto make photocopies for non-profit educational classroom use.
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Tcl:+44 (0)1865843239 Fax: +44 (0)1865 843971 E-m ail: smartmaterialsf elsevier.co .uk Imp:/lw\\w. manmarerialsbulletin.ccm Editor: reve Barrell Production Coordinator: Lin Lucas Permissions may be sought directly from Elsevie, Science Rights & Permissions Department, PO Box BOO. Oxford OX5 lOX, UK; phone: (+44) lB65 B43B30, fax: (+44) 1B65 B53333, e-mail: permissionsOelsevier. co.uk.You may alsocontact Rights & Pronissions directlythrough Elsevier's homepage (httpJI www.elsevier.nl). selecting first 'Customer Support', then 'General Information', then Permissions Query Form'. In the USA, use's mayclearpermissionsand make payments through the Copyright Clearance Center, lnc., 222 Rosewood Drive, Danvers. MA 01923, USA; phone: (97B) 750B4oo, fax: (97B) 7504744, and in the UK through the Copyrightlicensing Agency Rapid Clearance Service (ClARCS), 90 Tottenham Court Road, london WIP alP, UK: phone: (+44) 171 4365931 ; fax: (+44) 171 4363986. Other countriesmayhavea local reprographic rights agency forpayments. Derivative Works Subscribers mayreproduce tablesof contents or prepare listsof articles including abstracts forinternal circulation withintheirinstitutioos, Permission of the publisher is required for resale Of distribution outside the institution. Permissioo of the publisher is required forall otherderivative works. including compilations andtranslations. Electronic Storage or Usage Permissionofthe publisher is requiredto store or useelectronically anymaterial contained in thisjournal, including anyarticle or part of an article. Contact the publisher at the address indicated. Except as outlined above, no part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means. electronic. mechanical, photocopying. recordingor otherwise. without priorwritten permission of the publisher. Address permissions requests to:Elsevier Science Rights & PermissionsDepartment. at the rnail, fax ande-mail addresses noted above. Notice Norespoosibility is assumed by the Publisher for any injury andlor damage to personsor property as a matter of products liability, negligence or otherwise. or from any use or operation of any methods. products, instructions or ideascontained in the material herein. Because of rapid advances in the medicalsciences, in particular, independent verification of diagnosesand drug dosages should be made. Although all advertising material is expected to conform to ethical a guarantee or endorsement of the quality or valueof such product or of the claims made of it by its manufacturer.
Stretching and contracting molecules A new molecular device devised by Jean-Pierre Sauvage and colleagues at the Universite Louis Pasteur in Strasbourg, France works in a similar way to real muscle. Work reported in the 15 September issue of Angewandte Chemie International Edition describes an assembly of two molecules capable ofstretching and contracting when prompted by chemical signals - a 'molecular muscle'. Muscle cells are long, thin tubes divided into segments, each containing filamentary molecules that interpenetrate each other, To contract muscle, the tips of one filament type stick to the other's strands and pull themselves along to cause deeper interpenetration. The French team has devised twinned strands that can jump along one another to increase or decrease their combined length. This malces them like a muscle pair, except that in this case the two molecules are identical; and each molecule ends in a loop through which the tail of the other is threaded. Such structures are called rotaxanes, but these new rotaxanes are unusual because each of the paired molecules in the assembly acts as both hoop and thread, The researchers estimate that each 'contraction' shortens the rotaxane by about 27%, which is about the same as the maximum shortening in contracted muscle.
For more information, contact: Professor Jean-Pierre Sauvage, universlte Louis Pasteur, InstitutLe Bel, 4 rue Blaise Pascal, F-67070 Strasbourg Cedex, France. Tel: +33 3 8841 6130, Fax: +33 3 8860 7312, Email: [email protected]
C-MAC Industries to acquire Kavlico
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Montreal-based C-MAC Industries Inc, a leading designer and
manufacturer of fully integrated electronic systems and engineering solutions, has reached an agreement to acquire Kavlico Corporation, subject to regnlatory approval. Kavlico Corporation, with manufacturing operations In Moorpark, California and Minden, Germany is the largest independent supplier of precision sensors worldwide. It employs more than 220 research, development and engineering personnel, and holds numerous patents. Kavlico has established itself as a leading technology-driven manufacturer of precision measurement and control devices and systems in MEMS, ceramic capacitive, silicon piezoresistive and electromechanical technologies, 'We are very enthusiastic joining forces with C-MAC,' said Michael Gibson, president of Kavlico. 'CMAC gives us a global platform for growth while significantly expanding our product, technology base and service offering. This will enable Kavlico to deliver increasingly value-added solutions to our customers.'
For more information, contact: Kavlico Corporation, 14501 Los Angeles Avenue, Moorpark, CA 93021, USA. Tel: +1 805 523 2000, Fax: +1 805 523 7125.
Soundproofing drowns out deep . norse In a new soundproofing method reported by a team at the Hong Kong University of Science & Technology in the 8 September issue of Science, a material made of tiny, vibrating spheres pulses copies of a sound back towards its origin, and can block noise that passes through current soundproofing. The lab demo may be developed into thin, silencing sheets for residential use, while another application might protect buildings from seismic shocks.
Current soundproofing does not work well at low frequencies, because the longer wavelengths pass relatively unimpeded through the thickness of the material. About five times as much padding is needed to shield a 200 Hz sound as effectively as a 1 kHz sound. The team, led by physicist Ping Sheng, coated 1 em-diameter lead spheres with a thin layer of silicone rubber, then encased them in a hard matrix of epoxy. The spheres vibrate inside the soft silicone as though they were suspended by springs. When a sound with a frequency close to the spheres' resonant frequency enters the material, the spheres vibrate in their soft silicone sheaths, sending out sound waves in all directions. Some of those waves interfere with the forward movement of the offending noise, attenuating it. In testing of the material, the researchers could attenuate sound by 20 dB at both 400 Hz, the resonance ftequency of the spheres, and at 1.4 kHz, the resonant frequency of the silicone layer. By adjusting the materials, they could reduce noise at other frequencies. By stacking layers of differently tuned spheres, it should be possible to soundproof the entire sound spectrum,
For more information, contact: Professor Ping Sheng, Department of Physics, Hong Kong University of Science & Technology, Clear Water Bay, Kowloon, Hong Kong. Tel: +8522358 7506, Fax: +8522358 1652, Email: [email protected]
Project to study magnetic effect alloys A group of materials with an enhanced ability to cool and heat in response to changes in magnetic fields could have applications that extend far beyond temperature regulation. The materials, discovered at the US Department of Energy's Ames Laboratory in Iowa, could be used in versatile sensors to detect
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NEWS changes in magnetic field, temperature and pressure, and may be useful in energyconversion devices. Ames Laboratory is embarking on a four-year, DOE-funded project worth up to US$4 million, to gain a better fundamental understanding of the materials and why they respond so dramatically to changes in temperature and magnetic field. A team of metallurgists, physicists and chemists will explore the properties of the Gd-Si-Ge alloys and several closely related materials. The team will also develop theories and models that detail the relationship between the composition, structure and properties of the alloys, which could then be engineered for specific applications. In 1997 Ames Lab scientists Vitalij K. Pecharsky and Karl Gschneidner Jr. reported that the Gd-Si-Ge alloys possessed a giant magnetocaloric effect, such that the materials heated when magnetised and cooled when removed from a magnetic field. Subsequent work has discovered that the materials also possess giant magnetoresistance and colossal magnetostriction. Thus a relatively small change in the magnetic field surrounding the material produces a very large change in its temperature, dimensions and electrical resistance. This makes the alloys potentially useful in energy-conversion devices, such as systems that transform magnetic energy into mechanical energy and vice versa, or in sensors. The Gd-Si-Ge alloys can also be tailored to respond across a range of temperatures.
For more information, contact: Professor Karl Gschneidner Jr., Metallurgy & Ceramics, Ames Laboratory, 255 Spedding, Ames, IA50011-3020, USA. Tel: +15152947931, Fax: +15152949579, Email: [email protected]
Polymer patterns as glue in biochips Engineers at Purdue University in Indiana, USA have developed a
November 2000
technique to glue cells or DNA to the surfaces of computer 'biochips', a technology aimed at making diagnostic devices to be implanted in the body or used for rapid analysis of food and laboratory samples. It involves the preparation of micropatterned structures from thin films prepared by block copolymerisation of monomers using UV free-radical polymerisations. The microfabrication technique is used to fashion 'micropatrerns' out of a material made primarily
materials; to instantly analyse food products for contamination; and in future implantable medical devices
from a polymer, polyethylene glycol (PEG). Purdue engineers had already made the first protein biochips, in which a protein mated to a silicon chip might be used to detect chemicals, microbes and disease. The polymer micropatterning development represents a possible means of gluing these proteins, cells or DNA to a computer chip. The work was done primarily by doctoral research student Jennifer Ward, who presented her work in July at SPIE's 45th Annual Meeting in San Diego, California. 'The patterns' smallest features were 5 urn, which makes them as small as some cells,' says Rashid Bashir, an assistant professor of electrical and computer engineering at Purdue. 'This polymer layer could be the intermediate layer between the biological entities and the chip. The protein would go on top of the polymer.' The technique could be used to form precise polymer patterns containing certain regions that attract water and others that repel water. Specific cells or molecules could be encouraged to stick to the polymer. Then, the glued biological materials on a biochip's surface would precisely fit specific cells, molecules and strands of DNA in a
Selective detection of . . uranium Ions
sample being analysed. When a targeted substance passed by the chip, it would attach to the surface and the chip would signal that it had been detected. This could be used in the laboratory for rapid chemical and genetic screening of blood and other biological
that continuously monitor glucose in a diabetic's blood and then automatically administer insulin.
For more information, contact: Dr Rashid Bashir, School of Electrical & Computer Engineering, Purdue University, 1285 Electrical Engineering Building, West Lafayette, IN 479071285, USA. Tel: +1 765 4966229, Fax: +1 7654946441, Email: [email protected]
A device for the low-cost, portable selective detection of uranium(Vl) ions has been developed by scientists in the US. The analytical microchip is based on capillary electrophoresis and a calixarene molecular recognition host, and could enable environmental scientists to make rapid assessments of the contamination of groundwater and structural materials at decommissioned nuclear power plants and other installations. The highly portable glass microchip has the advantage of giving short analysis times, minimal sample consumption and waste generation. In the work, published in the 27 September Issue of Chemical Communications, Greg Collins and John Callahan of the Naval Research Laboratory In Washington, DC, working with Qin Lu of GeoCenters Inc in Rockville, Maryland report on the integration of a modified 4-sulfonic calix [6]arene, which selectively recognises uranium(VI) ions in the presence of other non-radioactive heavy metals, into a glass microchip. This calixarene has extremely high affinity and selectivity for uranium(VI). The modified molecule has a longwavelength, fluorescent tag that enables complexed UOl+ ions to
In Brief Chemistry Nobel prize for conductive polymers This year' obel Prize in Chemistry has been awarded jointly to Alan J. Heeger of the University of alifornia at anra Barbara. Alan G. MacDiarmid at the University of Pennsylvania in and Hideki Philadelphia. hirakawa of the University of Tsukuba in Japan. for the discovery and development of conductive polymers. The three mad their seminal findings in rhe late 1970s. and conductive polymers have subsequently developed inro a field of great importance. with significanr practical applications. Research on conductive polymers i also closely related 10 current rapid progress in molecular electronics. The prize, worth Kr9 million (U 930,000), will be shared equally among the Laureates.
Sensa acquires York Sensors In the UK . ensa Ltd has acquired York Sensors Lrd, which developed fibre-optic distributed rem perature sensing. The technique is now used extensively 10 monitor power distribution cables, detect leaks and monitor hot spots in refining. L G operations and petrochemicals as well as for downhole sensing in oil & gas production. The acquisition opens up new applications for ensa's technologies ro refining and delivery of electricity.
Standard MEMS facility randard MEMS Inc is to build a MO -8 inch wafer manufacturing facility for MEM and inregrared discrer semiconductor in lrzeho • Germany in a joinr venture with Philips miconductors, part of Royal Philips Electronics. The facility will also conduct R&D on new MEM product in close collaboration with the nearby Fraunhofer Institute for ilicon Technology (I IT). as well as other European research institutes. The new facility will produce sensors, medical devices and telecom components for the European and other markets.
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NEWS be easily monitored on the microchip. The device was tested for its ability to detect VO/+ ions in the presence of six competing metal ions. Each metal ion was added to a test sample solution at a concentration of 10 mg/I. Introducing any of the six impurity metal ions to the recognition host in the absence of VO/+ had no effect on the electropherogram recorded for the host. However, when VO/+ was added an additional peak was observed, which indicates that the molecule could strongly complex VO/+ ions, even III the presence of impurities. For more information, contact: Dr Greg E. Collins, Chemistry Division, Naval Research Laboratory Washington, DC 20375, USA. Tel: +1 202 4043337, Email: [email protected]
Reducing residual stress in piezoelectric . ceramics Researchers at the University of Illinois have found a way to significantly enhance the performance of a piezoelectric ceramic film, by applying a mechanical bending stress to offset the effects of residual stress in the film. 'Understanding the effects of residual stress in piezoelectric ceramic thin films is critical for their design and optimisation as smart materials,' says Nancy Sottos, a professor of theoretical and applied mechanics at VIVe. 'Not only can we greatly improve their performance as tiny sensors and III microelectroactuators mechanical (MEMS) devices, we can also put the effects of residual stress to work in a unique patterning process to better incorporate these materials on electronic chips.' Significant stresses build up in piezoelectric thin-film structures during fabrication. Intrinsic stresses
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are caused by shrinkage and densification during drying and firing, and extrinsic stresses are induced on cooling due to the mismatch between the film and substrate thermoelastic properties. The residual stress increasingly affects the piezoelectric properties as films become thinner, 'It is difficult to selectively etch a ceramic, so standard subtractive chip processing techniques won't work well for some smart materials,' Sottos said. 'But, methods to first pattern a substrate with a special polymeric monolayer and then lay down the ceramic film have recently been developed at Illinois. The film will adhere to the exposed substrate, but not to the monolayer. Residual stress induced in the film during drying will cause it to crack off the monolayer with extremely clean edges.' For more information, contact: Professor Nancy R. Sottos, Department of Theoretical & Applied Mechanics, University of Illinois at UrbanaChampaign, 216Talbot Laboratory, MC262, 104South Wright Street, Urbana, IL 61801, USA. Tel: +1 2173331041, Fax: +1 217244 5707, Email: [email protected]
EU invests in material technologies More than 400 million (US$470 million) has been dedicated to research into new materials and associated technologies under the European Union's current research budget. Half of this money is already allocated, while the remaining 200 million will be spent on projects in key areas including nanoscale research, surface technologies, and functional materials such as biomaterials and optoelectronics. Innovative research and production technologies represent one of the mainstream activities of the 'Growth' programme, to support European industrial competitiveness and its sustainable development. This programme
reptesents nearly 20% of the entire EU research commitment under the Fifth Framework R&D Programme (I 998-2002). The Growth programme aims to encourage a multidisciplinary, panEuropean approach. Half of the project proposals come from companies, with half of these from small and medium-sized enterprises (SMEs). Through measures for and networking, clustering coordination of activities, Growth provides bridges between the academic and business communities in an effort to produce sustainable research solutions that will foster European economic growth. This call is open for proposals until April 2002, while a new call for project proposals to the Growth programme and a new evaluation procedure will be published by the EC before the end of 2000. For more information, contact: Growth Programme, DG XII, European Commission, Rue dela Loi 200, M075, B-1 049Brussels, Belgium. Tel: +32 2 295 2345, Fax: +32 2 2966757, Email: [email protected], http://www.cordis.lu/growth
Sandia spin-off to commercialise microsystems Sandia National Laboratories in Albuquerque, New Mexico has spun off a private company, MEMX Inc, to commercialise its microsystems technology. The new company will initially focus on producing optical switches for the telecoms industry using SUMMiT V, an advanced fivelevel polysilicon surface micromachining MEMS technology claimed to produce more reliable and complex devices. Sandia, a US Department of Energy national laboratory, is a leader in microelectromechanical systems (MEMS) and microsystems technologies. David Williams, director of Sandia's Microsystems Science, Technology &
Components Center, says MEMX will be the cornerstone of the new microsystems industry that Sandia and others are striving to create. of any 'Commercialisation emerging disruptive technology is a challenge,' he says. 'We believe that small and entrepreneurial companies are key to getting the into widespread technology applications. MEMX will play a critical role in achieving this objective.' 'Optical switching applications are a driving force in the MEMS arena right now,' says Paul McWhorter, one of the company founders. MEMX has licensed Sandia's unique intellectual property, and plans to advance the technology aggressively. It will use manufacturing facilities at Sandia's Microelectronics Development Laboratory to produce its first prototype, but plans to quickly build its own device fabrication facility. For more information, contact: W. David Williams, Microsystems Science, Technology & Components Center, Sandia National Laboratories, Albuquerque, NM87185, USA. Tel: +1 505844 7659, Email: [email protected] Or contact: MEMX Inc, 5600 Wyoming Boulevard NE, Suite 160, Albuquerque, NM87109, USA. Tel: +1 5058581062, Fax: +1 505 858 0935, Email: [email protected]
Sandwich organic LEOs Researchers at Queen Mary & Westfield College in London and the University of Surrey have worked out how to directly integrate optical information technology with silicon circuits. Their approach, reported in Applied Physics Letters, is to find an electroluminescent material that will sit on the silicon surface, in this case using a sandwich of two organic materials. In optical fibre communications, the signals are electronically encoded and decoded by silicon
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NEWS microprocessors, which makes for an unwieldy interface. Optical signals are created by miniaturised light-emitting diodes and lasers made from semiconducting materials, which exhibit electroluminescence when an electric current is passed through them. However, silicon is difficult to electroluminesce, and so other semiconductors are used, normally alloys of gallium, indium and arsenic. The problem with these III -V materials is that the distance between the atoms of the III-V crystals differs from the distance between Si atoms on the wafer surface, and so III- V LEDs are awkward to attach to silicon circuits. If these devices could be made from silicon, the mismatch would not occur, but normal crystalline silicon is a very poor light emitter. A team led by QMW's William Gillin has now suggested an electroluminescent sandwich of two organic materials that will sit comfortably on a silicon surface. The first layer (N, N'-diphenylN,N' -bis(3-methyl)-I, i' -biphenyl4,4'-diamine) is a mediator, and carries the electric current from the silicon to the light-emitting top layer, erbium tris(8hydroxyquinoline). This electroluminescent layer consists of organic molecules wrapped around atoms of erbium, which emit infrared light at the standard telecoms wavelength of 1.5 pm. A top aluminium layer connects to the LED. The group admits that this 'organic LED' (OLED) is still very much a prototype. It requires a very high driving voltage of 33 V, and 99.99% of the electrical energy is not converted to light. Nevertheless, the team is confident that it can resolve these problems, in view of other groups' work with OLEDs on non-silicon surfaces that turn on at only 2.5 V. For more information, contact: Dr William Gillin, Department of Physics, Queen Mary & Westfield College, Mile End Road, London E1 4NS, UK. Tel: +44 207882 5524, Fax: +44 20 8981 9465, Email: [email protected]
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Ansys, Memscap in strategic OEM agreement Pennsylvania-based Ansys, a leader in advanced CAE software, has signed a long-term business and technology agreement with Memscap in California, a leading provider of commercial MEMS design technology, to offer a unified development environment for design and analysis of MEMS-based products. The new development environment from Mernscap, which includes an integrated Ansys/Multiphysics TM, is called MEMS Xplorer (for Unix) and MEMS Pro (for PCs), and supports Cadence Design Systems, Mentor Graphics and Tanner EDA tools. The new integrated environment allows engineers to seamlessly pass data between Memscap and Ansys® tools, leading to a reduction in development time. Memscap will become a primary worldwide sales and support channel for the integrated environment in the burgeoning optical and wireless telecoms markets. This will also complement existing MEMS markets including automotive and information technology, together with future technologies such as in the life sciences industry. For more information, contact: Memscap Inc, 180 Grand Avenue, Oakland, CA 94612, USA. Tel: +1510 4445269, Fax: +15104445287. Or contact: Ansys Inc, Southpointe, 275Technology Drive, Canonsburg, PA 15317,USA. Tel: +1 7247463304, Fax: +1 7245149494.
Wireless integrated microsystems The University of Michigan is to establish the first Engineering Research Center for Wireless Integrated MicroSystems
(ERCIWIMS) in the US, under a designation by the National Science Foundation. The Center will focus on developing miniature, low-cost integrated microsystems that gather information from their environment, interpret the data received, and communicate with a host system over bidirectional wireless links. The ERC/WIMS will be led by Professor Kensall D. Wise of the UM College of Engineering, with researchers involved from most engineering disciplines as well as computer science, chemistry, public health and medicine. First-year funding from the NSF IS US$2.5 million, with an additional $2+ million In contributions from a group of global corporations and partner universities. Funding over the 11year term of the ERC is anticipated to exceed $60 million. The integrated microsystems will combine a power source, software, an embedded microcontroller, a hardwired or wireless interface to the external world, and front-end microinstruments for the intended application in a single device roughly the size of a sugar cube. UM was selected for ERC status and funding based on its impressive track record in developing MEMS with wireless capabilities. Current interdisciplinary MEMS research projects at the College include work on implantable neural prostheses, a DNA-analysis lab on a microchip, and wearable environmental monitoring devices. Applications already under development at the university include neural probes, implantable drug-delivery systems, instant blood analysis, inertial sensors (accelerometers and gyros), biomedical stimulators, miniature flying machines, and resonators for cellular phones. For more information, contact: Professor Kensall D. Wise, Electrical Engineering & Computer Science, University of Michigan, 1301 Beal Avenue, Ann Arbor, MI481 09-2122, USA. Tel: +1 7347643346, Fax: +1 734 763 9324,Email: [email protected]
In Brief Continuum in seed financing ontinuum Control Corp., a leading provider of integrated piezoelectric power systems, has closed its first round of financing 10 raise U I million, led by the Massachusetts Technology Development orporarion, Continuum requires additional capital to expand its product development and marketing. to identify. prioritise and pursue opportunities to int grate its il'ower" technology into other products. Motorola awarded key DNA detection patents Clinical Micro ensors (CM ), a division of Motorola Inc, has received five strategically important U patellts covering novel bioelectronic detection technologies. Its e ensor™ system consists of disposable biochip cartridges. propri tary software and electronic readers, and is well suited to userfriendly. rapid and cost-effective D A tests in a wide range of markets. The patellts cover methods and compositions for detecting nucleic acids, including modifying electrodes with electronically linked oligonucleotides. and m thods and compositions for bioelectronic detection employing cycling probes. The system employs small D A biochips containing electronically active electrodes coated with specific D A probes. As these probes on the chip's surface capture specific target D A present in the sample. unique and characteristic electrical ignals are generated. Kymata acquires TMP UK-based Kymara Ltd has acquired Total Micro Products (TMP) in Enschede, The etherlands for an undisclosed amount. The acquisition will create new opportunities for Kyrnara to supply products based on MEM technology. TMP is a MEM facility providing design, fast-track prototyping manufacturing services in optoelectronics and industrial instrumentation.
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