Symposium M
Next Generation Micro/Nano Systems

Session M-1 - Physical MEMS/NEMS

M-1:IL01  Fluidic Physical Sensors and Sensor Systems
B. JAKOBY, Institute for Microelectronics and Microsensors Johannes Kepler University Linz, Austria

Silicon-based MEMS technology has furthered the introduction of sensors and actuators in many applications. Particularly in inertial sensing, where no contact with a medium to be sensed is required, highly reliable and cost-effective solutions have been developed. For application in fluidic environments, special demands regarding the interaction can occur. Also, silicon-based technology is not cost-effective in low-volume applications. In our recent work, we thus consider hybrid technologies and concentrate on physical sensor principles, which often provide more robustness in process control and condition monitoring than dedicated chemical sensors featuring chemical reactions with the environment by means of specific chemical interfaces. The latter are frequently prone to reliability issues, e.g. due to poisoning, drift, etc. Examples for physical parameters are thermal and electrical conductivity, permittivity, viscosity, speed of sound, and density. In this contribution, sensing concepts addressing these target parameters are reviewed. We discuss issues arising with complex fluids, suitable sensor designs in different technologies and illustrate these aspects by means of examples.


M-1:IL02  Nanophotonic Structures made from Diamond
W. PERNICE, P. RAITH, University of Muenster, Muenster, Germany

Outstanding optical and mechanical properties make diamond a pristine material for applications in photonics and optomechanics. The availability of large area polycrystalline diamond thin films has enabled the use of established nanofabrication methods for realizing advanced integrated photonic circuits for harnessing this potential. I will present a suite of chipscale components which can be used to develop diamond photonic devices with additional mechanical degrees of freedom provided by free-standing nanomechanical resonators. These devices enable all-optically tunable components using gradient optical forces, or also electromechanically tunable components using opto-electro-mechanical resonators. Through the combination with integrated single photon detectors a powerful framework is realized for emerging diamond quantum photonic circuits which can be reconfigured during measurement.


M-1:IL03  Emerging MEMS Devices and Exploitations in the Internet of Things Scenario
J. IANNACCI, G. SORDO, Fondazione Bruno Kessler-FBK, MicroSystems Technology-MST, Research Unit Center for Materials and Microsystems-CMM, Povo, Trento, Italy

Since its first demonstrations and commercial exploitations in the 80s and 90s, MEMS (MicroElectroMechanical-Systems) technology exhibited pronounced flexibility and adaptability in the realisation of miniaturised sensors and actuators for various applications. Nowadays, MEMS components like inertial sensors, gyroscopes, micro-mirrors, and so on, are widely diffused in diverse consumer market segments, e.g. mobile handsets, projectors, printers, cars, etc. On a different perspective, the Internet of Things (IoT) paradigm is emerging as the common denominator of different applications, providing connectivity, interoperability and communication of smart entities (e.g. cities, buildings, factories, etc.) within pervasive networks. The realisation of the radical change envisaged by the IoT urges for improvements both at software and hardware level. With focus on the latter one, integration, sensor fusion, ultra-low power consumption as well as energy autonomy are the keywords for success of the paradigm, and MEMS technology represents a key enabling platform for their achievement. In this contribution, an overview of the more promising classes of MEMS devices for exploitations in the IoT scenario will be provided, with a particular focus on RF-MEMS and Energy Harvesting.


M-1:L04  Coupled Effects in Low Dimensional Nanosystems and their Applications
R.V.N. MELNIK^{1, 2}, S. PRABHAKAR¹, ¹MS2Discovery Interdisciplinary Research Institute, Wilfrid Laurier University, Waterloo, ON, Canada; ²BCAM, Bilbao, Basque Country, Spain

In a series of recent papers we demonstrated that coupled electro-mechanical effects can lead to pronounced contributions in bandstructure calculations of low dimensional semiconductor nanostructures (LDSNs) such as quantum dots and nanowires. Both strain and piezoelectric effects have been used as tuning parameters for the optical response of LDSNs in photonics and band gap engineering applications. However, thermal effects have been largely neglected. At the same time, thermal effects coupled with electric and mechanical fields in LDSNs are becoming increasingly important in many applications of LDSN-based optoelectronic and smart devices, in particular where such devices face challenges for thermal management. Indeed, as thermoelectric and thermoelastic effects are often significant in LDSNs, it is reasonable to expect that the temperature may also be used as a tuning parameter in photonics and band gap engineering applications. In this contribution, by using the fully coupled model of thermoelectroelasticity, we build on our previous results while analyzing the influence of these effects on optoelectronic properties of quantum dots. Results are reported with a major focus given to quantum dot based systems, as well as their biomedical and other applications.

 
Session M-2 - Chemical Micro/Nano-sensors and Systems

M-2:IL01  Chemical Microsensors and Microsystems for the Food Industry
C. JIMENEZ-JORQUERA, Instituto de Microelectrónica de Barcelona (IMB-CNM), CSIC. Campus UAB, Bellaterra, Spain

The increasing interest on a sustainable and high quality production in agriculture and food industry and the requirements of a more strict legislation entails for more automated and precise analytical systems. Currently analyses are performed with conventional techniques which are time-consuming and require costly laboratory equipment. On the other hand, panels for sensory analysis suffer from drawbacks, like discrepancies due to human fatigue or stress, and clearly cannot be used for online measurements. Therefore, the market is demanding for smart analytical systems that allow faster and more accurate monitoring of agro-food processes, as well as to assure quality control of final products. In this context, microsensors and multisensor microsystems play an important role since they fulfil the above mentioned requirements while being able to be implemented in a miniaturized equipment. Besides, multisensor systems combined with chemometric tools, also called Electronic Tongues, are especially suitable for sensory analysis and quality control of food. In this presentation, an overview of the state of the art of these kinds of systems applied to food analysis and more specifically the work performed with microsensors fabricated with semiconductor technology will be presented.


M-2:L03  Fabrication of Micro Three Dimensional Structures by Two Photon Polymerization with SiO/Resin 
M.G. del R. HERRERA-SALAZAR, H. AKIYAMA, T. NAKAYAMA, H. SUEMATSU, T. SUZUKI, Y. YOSHITAKE, N. YAMADA, T. TAKAHASHI, K. NIIHARA, Nagaoka University of Technology, Nagaoka, Niigata, Japan

In this paper we presented the synthesis of TEOS with photoresist In order to use it like a hybrid material for 3D printer on the micrometer scale by means of the two-photon polymerization process, In which two photon are absorbed simultaneously by the material using an ultrafast laser causing its polymerization. We analyzed the mix of TEOS and photoresist with UV-VIS and FTIR spectrometers, checking that complies with two important conditions: has an optical transmission at 780 nm and absorbs at 390 nm. Finally we fabricated microstructures with a new hybrid material; TEOS does not absorb the laser in this system and does not interfere with the formation of a three-dimensional structure. After formation the 3D microstructure, samples were heated to form the SiO. These samples of microstructures were observed under digital microscope and SEM.


Session M-3 -  MOEMS/NOEMS

M-3:IL01  Optical MEMS for Telecom Application
M. NAKAJIMA, J. YAMAGUCHI, NTT Device Technology Laboratories, Atsugi-shi, Kanagawa, Japan

Optical device based on microelectromechanical systems (MEMS) have been intensively studied because they have many attractive advantages for telecommunications devices: they can manage a large number of optical paths dynamically with a configuration based on free space optics; achieve superior optical characteristics to conventional waveguide-based devices; and be mass-produced at low-cost, and so on. In this paper, we review recent developments of optical MEMS for telecom devices. First, we will overview MEMS-based telecom devices such as optical switches, filters, dispersion compensators, variable optical attenuators, and tunable lasers. As we cannot cover all of these developments in detail, we will focus on optical switches because they have already been installed into practical networks and because the demands for these devices are expanding. We will introduce various types of optical switches, including a simple 1xN switch, an NxN optical crossconnect (OXC), and a wavelength selective switch (WSS). In addition, we will introduce optical switches based on liquid crystal on silicon (LCOS), which are the competitive with MEMS-based devices. We will compare the features of the LCOS-based optical switch with the MEMS-based one and discuss their potential for future networks.


M-3:IL02  Optofluidic Sensors and Actuators
M.J. VELLEKOOP, M. OELLERS, University of Bremen, Institute for MicroSensors, -Actuators and -Systems (IMSAS), MCB, Bremen, Germany
 
In optofluidic devices, liquids are a part of the functional optical path. The optical properties of a microchannel acting as the optical path can easily be adjusted by exchanging one liquid with another. The span of operation of such optofluidic devices can be much larger than the case where only solids are used. It also allows the realization of completely new devices that are not possible with solids. In this contribution, an overview is given of sensors and actuators that apply optofluidics as a basis for their function. Also the fabrication technology of devices in which optics and microfluidics need to be coupled will be addressed. Device examples are light modulators, chemical sensors, and interferometers.


M-3:L03  Advanced Protective Coatings by Low Temperature Atomic Layer Deposition of HfO2 on Al Surfaces for Micro-mirror Applications 
C. WIEMER, E. CIANCI, A. LAMPERTI, G. TALLARIDA, Laboratorio MDM, IMM-CNR, Agrate Brianza (MB), Italy; M. BERDOVA, S. FRANSSILA, Aalto University, Department of Materials Science and Engineering, Espoo, Finland; M. ZANUCCOLI, C. FIEGNA, Department of Electrical, Electronic and Information Engineering (DEI), Università di Bologna and IUNET, Cesena (FC), Italy; L. LAMAGNA, S. LOSA, S. ROSSINI, R. SOMASCHINI, S. GIOVENI, STMicroelectronics, Agrate Brianza (MB), Italy

The integration of micro-projectors into portable devices requires the miniaturization of well-known systems like Al-based micro-mirrors. To face the different steps of the process flow, miniaturization requires an appropriate protection of the Al surface. Due to its high conformality and adhesion characteristics, excellent thickness and chemical control, atomic layer deposition (ALD) can be the technique of choice for the deposition of protective nano-layers on miniaturized, highly reflective surfaces. The ALD process at low temperature of HfO2 thin films and the reflective performances of coated Al surfaces are analyzed. HfO2 is proven to be resistive to thermal treatments in humid atmosphere and the underlying Al surface results so to be protected. Optical reflectivity data show slight modifications induced by the thermal treatment that are ascribed to the non-perfect impermeability of the HfO2 coating, causing modification of the Al itself. Advanced calculations by transfer matrix method (TMM) allow to predict enhanced reflectivities within the 420 – 675 nm wavelength range by combining SiO2 and HfO2 of selected thickness as protective stack for Al. Results are promising for the integration of ALD based layers on advanced micro-mirror devices.


M-3:L04  Optical MEMS Technologies for Infrared Spectroscopy, Sensing and Imaging 
D. SILVA, J. ANTOSZEWSKI, A. KEATING, J. DELL, L. FARAONE, The University of Western Australia, Crawley, WA, Australia

Improving current state-of-the-art infrared (IR) detector and focal plane array (FPA) technologies is focused on reducing cooling requirements, larger-format FPAs, extending to longer wavelengths, and/or adding so-called multi-colour capability, which allows real-time spectral information to be gathered from multiple wavelength bands. Multi-spectral imaging results in improved target recognition and reduced false alarm rates in military scenarios, and is applicable to numerous remote sensing spectroscopy/imaging applications in civilian arenas. In order to provide a reduced size, weight and power (SWaP) solution, a micro-electromechanical systems (MEMS) based electrically tuneable Fabry-Perot optical filter technology has been developed that is compatible with individual detectors or large format 2-D imaging IRFPAs. Such a hybridised technology is capable of low-voltage tuning across the NIR/SWIR and MWIR wavelength bands for field-portable spectroscopy applications and/or for remote sensing and imaging applications. This presentation will focus on current research work to extend the technology into the VIS/NIR and LWIR wavelength bands, as well as presenting recent results on successful approaches to extending the technology to very large area imaging FPAs.


Session M-4 -  Smart Micro-nano System and Components Integration

M-4:IL01  Giant Piezoelectric Materials for Microelectromechanical Systems
M.S. RZCHOWSKI, Physics Department, University of Wisconsin-Madison, Madison, WI, USA

Microelectromechanical systems (MEMS) incorporating active piezoelectric layers offer integrated actuation, sensing, and transduction. The key to their development is the incorporation of active materials with giant piezoelectric response. We have synthesized high-quality Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT) on a variety of substrates, including oxide single crystals, oxide-buffered (001) Si wafers, as well as membrane-supported PMN-PT films transferred from oxide substrates. We present structural and electromechanical characterization of these films, and discuss the thin-film phase diagram. We have incorporated these heterostructures into microcantilevers1 that are actuated with extremely low drive voltage due to thin-film piezoelectric properties that rival bulk PMN-PT single crystals. These epitaxial heterostructures exhibit very large electromechanical coupling for ultrasound medical imaging, microfluidic control, mechanical sensing, and energy harvesting.
1.S.H. Baek et al, Science 334, 958 (2011); MRS Bulletin 37, 1022 (2012).
Work done in collaboration with S. H. Baek, J. Park, D. M. Kim, V. A. Aksyuk, R. R. Das, S. D. Bu, D. A. Felker, J. Lettieri, V. Vaithyanathan, S. S. N. Bharadwaja, N. Bassiri-Gharb, Y. B. Chen, H. P. Sun, 
C. M. Folkman, H. W. Jang, D. J. Kreft, S. K. Streiffer, R. Ramesh, X. Q. Pan, 
S. Trolier-McKinstry, D. G. Schlom, R. H. Blick, C. B. Eom


M-4:IL02  MEMS Sensor for Personal Nanoparticle Monitoring
H.S. WASISTO, W. WU, E. PEINER, TU Braunschweig, Inst. of Semiconductor Technology and LENA, Braunschweig, Germany; E. UHDE, Fraunhofer-WKI, MAIC, Braunschweig, Germany

Ambient air quality is defined by concentrations of pollutants, e. g., particulate matter, among which nanoparticles (NPs) are considered to be most hazardous for human health. NPs may be released to the environment during fabrication or handling of engineered nanomaterials (carbon, titania, …) or incidentally, e.g. by combustion processes based on fossil fuels. Personal monitoring of NPs close to the breathing zone is a pragmatic approach to protect exposed persons from inhaling NPs in health-affecting concentrations. Unfortunately, commercially available pocket-size instruments are either expensive or not sensitive enough to detect such tiny NPs. Therefore, we developed a MEMS–based NP monitor (Cantor), which contains a micromachined silicon cantilever resonance balance, an electrophoretic sampling unit. NPs suck into the sampler are directed to the cantilever and stick there thus changing its mass. The resulting resonance frequency shift is taken as a quantitative measure of the NPs concentration in the ambient air. Our prototype Cantor is a battery-powered direct-reading instrument offering a limit of detection of 5 µg/m3, which can be worn in a pocket. We checked its quantitative NP monitoring ability with a number of relevant materials (carbon, titania, silica, silver).


M-4:L03  Effect of Interfacial Incompatibility on the Stability of 3D Electronic Packages containing Through Silicon Vias (TSV) 
I. DUTTA, H. YANG, M. UPADHYAYULA, L. MEINSHAUSEN, T.K. LEE*, School of Mechanical and Materials Engineering, Washington State University, Pullman, WA, USA; *Dept. of Mechanical and Materials Engineering, Portland State University, Portland, OR, USA

3D microelectronic packages comprise stacked chips interconnected by through-silicon-vias (TSV). This results in greater functionality, along with much greater performance and lower energy consumed. However, the high interfacial area between Cu filled TSVs and the Si can cause interface-related phenomena, which, can result in intrusion or protrusion of the Cu vias relative to Si. This intrusion/protrusion occurs due to a combination of plastic deformation and diffusionally accommodated interfacial sliding, which is driven by a combination of stress and electromigration. Because of this interfacial compatibility, the redistribution layer (RDL) can be strained, and give rise to deformation, delamination and chip warpage. In this paper, we report on TSV protrusion/intrusion during thermal cycling (TC) and EM experiments in a chip containing 10µm diameter Cu filled vias. Experiments are first conducted on chips with and without an RDL to first elucidate the extent of plastic deformation and interfacial sliding. The effect of different thermal excursions and electric currents on TSV protrusion/intrusion and migration are examined. Then, experiments are conducted on chips with an RDL to show the effect of TSV migration on RDL stability. Results of modeling are also reported.


M-4:L04  Artificial Intelligence integrated Multiscale, Multiphysics Computational Methods for Smart and Multifunctional Materials 
A. MIYAMOTO, P. BONNAUD, R. MIURA, A. SUZUKI, N. MIYAMOTO, N. HATAKEYAMA, M. HARIYAMA, Tohoku University, Sendai, Miyagi, Japan

Much attention has been given to innovation in smart and multifunctional materials and their applications to many industrial targets. In collaboration with many experimental/industrial experts, the authors have been developing a variety of computational chemistry software for the design of such materials [1-9]. The Ultra-Accelerated Quamtum Chemical Molecular Dynamics(UA-QCMD) method is very useful for multiscale, multiphysics simulations of such chemical systems because the UA-QCMD method can perform quantum molecular dynamics calculations 10,000,000 times faster than a conventional first principles molecular dynamics method. In the present study we tried to integrate artificial intelligence approach to such multiscale, multiphysics computational methods for smart and multifunctional materials.
[1]H. Malani, Topic. Catal. 52 , 724 (2009). [2] A.R. Shaikh, J. Inorg. Biochem., 103, 20 (2009). [3] A. Suzuki et al., Surf. Sci. 603, 3049 (2009). [4] M.K. Alam et al., J. Phys. Chem. C 113, 7723(2009). [5] F. Ahmed et al., J. Phys. Chem. C 113, 15676 (2009). [6] A. Suzuki et al., SAE Int. J. Fuel and Lub. 2, 337 (2010). [7] T. Onodera et al., J. Phys. Chem. B 114, 15832 (2010). [8] F. Ahmed et al., J. Phys. Chem. C 115, 241123 (2013). [9] S. Loehle, Tribol. Lett. 53, 319 (2014)


M-4:L05  Shape Memory in Micro-patterned Thiol-ene Thermoset Pillars
W. VOIT, J. SALAZAR, A. JOSHI-IMRE, The University of Texas at Dallas, Richardson, TX, USA

Strain recovery in shape memory polymers may be utilized at the micro scale to fabricate switchable surfaces. Thin film thiol-ene thermoset polymers were patterned via photolithography and reactive ion etching (RIE) to create polymer pillar arrays 30 to 80um wide at the base and 50um tall that can be imprinted. The pillars have a conical shape due to the RIE which aid in imprinting. The shape imprint and recovery processes were demonstrated as follows. The pillars are deformed to a near flat shape by applying appropriate pressure while they are in the rubbery state, and then cooled to lock them into a near flat shape in the glassy state. Upon reheating above the glass transition temperature the pillars return to their original shape. This allows the pillars to switch between the two forms. The glass transition temperature can be tuned by altering the ratio of acrylate in the network [ref]. It was found that strain recovery in micron scale shape memory polymer allows flattened pillars to return to their original shape making it possible fabricate surfaces that switch between 2 surface geometries. As a result of the specific pillar geometry the surfaces show omniphobic behavior.


Session M-5 -  Radio Frequency MEMS

M-5:IL01  RF MEMS Applications to RF Tuneable Circuits
R. SORRENTINO, University of Perugia, Perugia, Italy; A. CAZZORLA, P. FARINELLI, L. PELLICCIA, RF Microtech s.r.l. Perugia, Italy

The bursting wireless communication market, including 5G, advanced satellite communication systems and COTM (Communication On The Move) terminals, require ever more sophisticated functions, from multi-band and multi-function operations to electronically steerable and reconfigurable antennas, pushing technological developments towards the use of tunable microwave components and circuits. Reconfigurability allows indeed for reduced complexity and cost of the apparatuses. In this context, RF MEMS (Micro-Electro-Mechanical-Systems) technology has emerged in as a very attractive solution to realize both tunable devices,(e.g. variable capacitors, inductors and micro-relays), as well as complex networks, (e.g. tunable filters, reconfigurable matching networks and reconfigurable beam forming networks for phased array antennas). High linearity, low loss and high miniaturization are the typical advantages of RF MEMS over conventional technologies. Micromechanical components fabricated via IC-compatible MEMS technologies and capable of low-loss filtering, switching and frequency generation allow for miniaturized wireless front-ends via higher levels of integration. In addition, the inherent high linearity of the MEMS switches enables carrier aggregations without introducing intermodulation distortions. This paper will review the recent advances in the development of the RF MEMS to RF tunable circuits and systems, highlighting their advantages as well as the still open issues.


Session M-6 - Energy Harvesting and Power Supply MEMS

M-6:IL01  Single-use Paper Fuel Cells
N. SABATE, Institució Catalana de Recerca i Estudis Avançats (ICREA) and Institut de Microelectronica de Barcelona (IMB-CNM-CSIC), Campus UAB, Bellaterra-Barcelona (Spain); J.P. ESQUIVEL, Department of Bioengineering, University of Washington, Seattle, WA, USA

Fuel cells are electrochemical power sources that generate electrical energy from the oxidation of a fuel. Their high energy density and possibility to operate at room temperature using liquid fuels identified them as very promising power sources for portable applications more than a decade ago. Despite all the advances and performance improvements achieved in this area, it is clear that batteries have shrunk more efficiently than micro fuel cells: batteries are tiny packages very easy to use, rechargeable and able to meet the power demands of current portable applications. In contrast, state-of-the art micro fuel cells are miniaturized versions of larger prototypes requiring ancillary components such as pumps or fuel reservoirs that increase their volume and diminish significantly the overall power density of the device. In this sense, the use of paper as main material for fuel cell implementation allows taking advantage of capillarity and eliminates the need of ancillary pumps, which extremely simplifies the device. At the same time, paper will allow to develop a new generation of power sources with low environmental impact. This supposes a paradigm break in the fuel cell field, as these devices are now conceived for the first time as single-use and disposable power sources.


M-6:IL02  Alternative Power Sources for Microdevices
P.D. MITCHESON, Imperial College London, London, UK

Energy harvesting, which in the modern literature can be traced back to the late 90s, has been thought of as a ground breaking substitute for exhaustible energy sources for powering miniature devices. However, there are still very few areas in which harvesters, at either the MEMS or macro-scale, have made significant impact. In comparison, a different technological solution to the same problem, that of wireless power delivery, either as near or far field electromagnetic transfer, is already gaining traction in several areas from charging electric vehicles to powering wireless sensors. In this talk I will review the state of the art in each of these areas, discuss current innovations and discuss and compare the potential for future development of these two alternatives to batteries.


M-6:L03  Comparison between MEMS and Meso Scale Piezoelectric Energy Harvesters 
A.D.T. ELLIOTT, L.M. MILLER; E. HALVORSEN; P.K. WRIGHT; P.D. MITCHESON, Department of Electrical and Electronic Engineering, Imperial College London, London, UK; Alphabet Energy, Hayward, CA, USA; Buskerud and Vestfold University College, Drammen, Norway; University of California, Berkeley, CA, USA; Department of Electrical and Electronic Engineering, Imperial College London, London, UK

Manufacture of piezo energy harvesters typically assumes bulk piezo material for the transducer until the reduction in size of the device prevents this. However when designing piezo harvesters, the complete system must be taken into account including the transducer, power circuit, and battery, as these will impose restrictions on what can be achieved. Therefore a comparison between MEMS and meso scale piezo energy harvesting systems using a fully parameterised model is required. The comparison was restricted to a piezo beam with a mass at the end connected to a single supply pre-biasing circuit to provide the optimal damping force and rectification. A buck converter was used to transfer extracted energy to a 1.5V battery. The results indicate that for devices with a volume side length less than 16.25mm, no device using meso scale properties can be made to resonant at 100Hz or less due to the length and stiffness of the beam. Whereas above this limit, the voltage required to damp devices with MEMS scale properties causes a breakdown in the dielectric. We present a comparison of the theoretical limits of MEMS and meso scale piezo harvesters. The limits are compared with what has been practically achieved to provide design insight for future devices to maximise power generation.


Session M-7 - Micro(nano)fluidics and Lab on Chip; Bio-MEMS/NEMS

M-7:IL02  Soft-interface Design for Highly Sensitive Biosensor 
MADOKA TAKAI, The University of Tokyo, Tokyo, Japan

The soft-interface to immobilize proteins such as enzyme and antibody for obtaining high-sensitivity on biosensor is designed. Signal enhancement of the biosensor for instance immunoassay is achieved by the increase the amount of immobilized antibody also the orientation control of immobilized antibody. Moreover the decrease of non-specific protein adsorption is the necessary function to decrease the noise. Two typed bio-conjugated soft-interfaces to be achieved highly sensitive immunoassay were developed by integrating a phospholipid polymer, which is cell-membrane mimetic material. Nano-sphered surface with poly [2-methacryloyloxyethyl phosphorylcholine (MPC) -co- n-butyl methacrylate (BMA) -co- p-nitrophenyloxycarbonyl poly(ethylene glycol) methacrylate (MEONP)]: PMBN) was prepared by electrospray deposition method. The highly sensitive immunoassay was established by use of the nano-sphered PMBN surface. As the other platform, we developed a novel soft-interface consisting of a well-defined phospholipid polymer surface on which Staphylococcal Protein A was site-selectively immobilized. Theoretical multivalent binding analysis further revealed that orientation-controlled antibodies had antigen-antibody reaction equilibrium dissociation constants as low as 8.6 × 10-10 mol/L.


M-7:L04  Gas Supply through Agarose Walls in Cell Culturing Microchips
F. BUNGE, S. VAN DEN DRIESCHE, M.J. VELLEKOOP, Institute of Microsensors, -actuators and –systems (IMSAS), MCB, University of Bremen, Germany

We present a novel structure to supply gases to microfluidic chips. An example is the continuous feeding of oxygen and CO2 for on-chip cell cultivation of mammalian cells. In our device, the surrounding air diffuses into the culture medium inside the chip through a porous wall of agarose hydrogel resulting in an easy and robust design. One common method is the usage of gas permeable PDMS chips. However liquid medium in which the cells grow is absorbed by PDMS causing unknown concentrations and memory effects. Another possibility is a complex setup where medium with already dissolved gas is pumped constantly through the chip. We designed and realized a silicon and borosilicate glass chip containing a gas permeable wall of agarose preventing leakage of medium. In order to precisely position the walls in the chip, we made use of surficial phaseguides (100nm high). The blue-bottle-experiment makes the effective dissipation of oxygen visible when the colorless leucomethylen-blue reacts to methylene-blue. Successful results were achieved when applying 0.67 mg/l methylene blue, 10 g/l glucose and a pH of 12.6 set by a buffer solution. As a result a continuous color gradient through the chip was obtained, which directly reflects the oxygen gradient and confirms the oxygen diffusion.


Session M-8 -  Flexible Sensors Technology

M-8:IL02  Flexible Solution-processed Photodetectors and their Use in X-ray Medical Imagers’
A. KUMAR¹, D. MOET¹, J.-L. VAN DER STEEN¹, A. VAN BREEMEN¹, S. SHANMUGAM¹, J. GILOT¹, R. ANDRIESSEN¹, M. SIMON², W. RÜTTEN², A. DOUGLAS², R. RAAIJMAKERS³, P.E. MALINOWSKI⁴, K. MYNY⁴, G.H. GELINCK^1,5, ¹Holst Centre/TNO, Eindhoven, The Netherlands; ²Philips Research, Eindhoven, The Netherlands; ³Philips Healthcare, Best, The Netherlands; ⁴Department of Large Area Electronics, imec vzw, Leuven, Belgium; ⁵Applied Physics Department, TU Eindhoven, Eindhoven, The Netherlands

Digital X-ray systems offer a number of benefits over older, analog systems. Images are available faster, are easier to share and can be achieved using less radiation. However, today’s digital X-ray sensors are still produced on large glass substrates, making them heavy, difficult to transport and prone to breakages. In this work we report an X-ray detector on a plastic substrate that is capable of medical-grade performance. An indirect flat panel detector (FPD), it combined a standard scintillator with a novel, solution-processed organic photodetector layer and oxide thin-film transistor (TFT) backplane. By using solution-processed organic bulk heterojunction photodiode rather than the usual amorphous silicon, the maximum process temperature is reduced to be compatible with plastic film substrates, and a number of costly lithography steps are eliminated, opening the door to lower production costs. The solution-processed photodetector exhibits the best performance of any bulk heterojunction photodetector studied to date, with very low dark current of 10-7 mA/cm2, and high sensitivity in the relevant wavelength range. The outstanding optical characteristics are retained when these photodiodes are combined with an array of low-temperature Indium-Gallium-Zinc-Oxide (IGZO) transistor switches on a 126-mm pitch on thin, plastic substrates. We show that the thermal and mechanical properties of the organic photodetector and transistor compare favourable to conventional amorphous silicon.

 
Poster Presentations

M:P02  A Wearable Swallowing Detecting Method based on Nanometer Materials Sensor
YI KANG, DONG-YI CHEN, M.L. XIA, SHI-JI HOU, Sichuan, China

Obesity and dysphagia are of potential and direct serious harm to the human body health. A commonly used method is controlling food intake to avoid obesity or determining if dysphagia exists by monitoring the swallow . This paper proposes a swallow detecting principle based on nanometer materials sensor, and implements a wearable detecting system with advantage of improved DTW algorithm. The system efficiently detects and faithfully identifies swallowing. In addition, it reduces the demand for hardware computing power. The system meets the features of a wearable system, such as soft and comfortable, lightweight, portable, and noninvasive.


M:P05  Sensor Sticker for Detection of Fungi Spore Contamination on Bananas 
P. PAPIREDDY VINAYAKA, S. VAN DEN DRIESCHE, R. BLANK, M. KAHALI MOGHADDAM, W. LANG, M.J. VELLEKOOP, Institute for Microsensors, -actuators and -systems (IMSAS), University of Bremen, Bremen, Germany

Fungi growth on bananas during transportation not only results in loss of food but it also incurs considerable transport losses. To investigate the influence of spores on the development of fungi growth on the bananas we present a sensor sticker. The sticker can be put on the banana surface for the detection of spore concentration. The designed sensor comprises of a thin layer of culture medium (PDA agarose, 500 µm) coated on a capacitive sensor fabricated on a polyimide foil (5 µm). As spores germinate, the capacitance of the culture medium changes which is measured by the interdigital capacitive element that contains 430 electrodes that have a length of 3 mm, a width of 7 µm and a gap of 7 µm. In addition to the culture medium one of the major requirements for the fungi to grow is air. As air cannot diffuse through the sticker, air cavities are integrated in the culture medium layer to provide the necessary amount of air for fungi growth. This method was successfully applied to determine different concentrations of Fusarium Oxysporum, a major fungi species responsible for banana contamination. Measured capacitance change after a fixed time interval depends on the initial concentration of spores. The measurement takes typically 6 hours.