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PID180145 |
Lab on a Chip : Advances in packaging for MEMS and Lab on a Chipa: CEA, LETI, Department Microtechnology for Biology and Health-care, France AbstractIn the field of bioMems or Lab on a Chip, one may have to handle fluid exchanges even at high pressure, moving parts, temperature sensitive probes. This specificity triggers huge packaging issues because most of the packaging techniques inherited from the microelectronic require thermal cycles at temperature above 350°C. In this paper, we first present the requirement of representative lab on chip projects carried out at the LETI in order to introduce two specific solutions of this field. Afterwards we present a brief review of the packaging processes used in the MEMS facilities eventually and introduce low temperature packaging processes developed at the CEA Leti to process lab on chip with MEMS and BioMEMS. We intend to develop robust and collective solutions (wafer level packaging). The first solution relies on a thin film approach develop for MEMS using silicon nitride cap on a sacrificial layer. The second one was especially designed for temperature sensitive lab on chips hence can be carried out at room temperature. Keywords: packaging, lab on chip, thin film, in line screen-printing |
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PID190079 |
Micro- and nano- structuring using ion beamsa: Eindhoven University of Technology, 5600 MB Eindhoven, the Netherlands AbstractIon beam techniques such as ion projection can be used to structure materials on micrometer and nanometer scales. It can complement current optical or e-beam lithography techniques for micro- or nanodevice fabrication. Besides ion beam lithography also direct ion beam structuring methods that do not rely on resist materials for the pattern transfer have been investigated. Local sputtering, magnetic nanopatterning and inducement of selective electroplating are examples for such resistless ion beam patterning techniques. A new type of instrument based on a parallel multibeam concept will allow combining high resolution with high throughput. Keywords: ion beam lithography, direct ion beam structuring, nanopatterning |
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PID203679 |
Micromoulding - Precision Processing for Controlled ProductsPolymer IRC/ Polymer CIC, School of Engineering, Design & Technology, University of Bradford, Bradford BD7 1DP, UK AbstractMicromoulding is an emerging field which has seen the evolution of conventional polymer injection moulding techniques for the manufacture of 3-dimensional components of sub-milligramme masses and/or microscale surface features. Micromoulding incurs extremely high strain rates and temperature gradients, particularly at the gate of the cavity. A range of issues associated with this, including high strain rate rheology of polymers (including experimental observation of in-cavity flows) and effects on orientation, residual stress and property developments, including surface replications have been explored in our laboratories and with collaborators. A major aim is to achieve controlled, repeatable dimensions and properties in micromoulded products, and to model this process - including molecularfeature models. The key factors determining control of precision products are discussed. Keywords: micromoulding, miniature, precision moulding |
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PID204302 |
Automatic Nanohandling Station inside a Scanning Electron MicroscopeDivision Microrobotics and Control Engineering, University of Oldenburg, D26111 Oldenburg, Germany AbstractCurrent research work on the development of an automated nanohandling cell in a scanning electron microscope (SEM) is presented. Two experimental setups are shown, in which nanohandling robots ooperate in the vacuum chamber of an SEM. A client-server control system that can integrate various microrobots and sensors has been developed and evaluated by automatic handling of TEM (transmission electron microscope) lamellae by two nanorobots. The robots are controlled in a closed-loop way by using images from several CCD cameras and from the SEM. Algorithms for real-time processing of noisy SEM images have been implemented and tested. The experiment on automatic handling of TEM lamellae inside an SEM is described. The other setup contains a nanohandling robot using the probe of an atomic force microscope (AFM) as an end-effector. The manipulation of individual multiwall carbon nanotubes (MW-CNTs) and the characterization of nanofilms by nanoindentation are the applications being investigated. The experimental setup includesf a nanopositioning piezo sample stage with three degrees of freedom (DoF) and a three-axes nanomanipulator. Piezoresistive AFM probes are applied as an end-effector. This way the acting forces can be detected allowing force feedback for the station's control system. First investigations have been carried out by bending of MWNTs and calculating their elastic modulus. Keywords: microrobotics, nanohandling automation, SEM image processing, nanocharacterization |
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PID208010 |
Recent Evolution of Electrical Discharge MachiningN. Mohri(a), T. Tani(b) a: Department of Precision Machinery Engineering, The University of Tokyo, Tokyo, Japan b: Tsukuba University of Technology, Tsukuba, Japan AbstractElectrical Discharge machining (EDM) is a comparatively new machining method which has several decades of history since it has been invented. At its beginning, it was developed as a precision machining method for hard materials. In recent years, several researches and methods based on the electrical discharge phenomena have been proposed. Mirror like finish machining, surface modification of mold die, machining of insulating materials and micro products manufacturing are noted among these researches and methods in the EDM field. These methods are particularly concerned with control of surface characteristics of the work piece and with control of electrode motion. In this paper, we introduce and discuss surface machining methods, insulating ceramics machining by EDM and micro EDM with which we have been associated. Keywords: Electrical discharge machining, Finishing, Surface modification, Insulating ceramics, Micro EDM |
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PID190055 |
A dynamics-driven approach to precision machines design for micro-manufacturing and its implementation perspectivesAMTRG, School of Technology, Leeds Metropolitan University, Leeds LS1 3HE, UK AbstractPrecision machines are essential elements in fabricating high quality micro product or micro feature and directly affect the machining accuracy, repeatability and efficiency. Some design issues of precision machines are presented in this paper, and emphasis is placed on the mechanical and structural design of precision machine and relevant design methodology. In the discussion of mechanical and structural design of precision machine, particular emphasis is placed on the machining dynamics issue to identify the major structural factors affecting the performance of the machining. This paper begins with a brief review of the design principles of precision machine tools, including tool-workpiece loops and machine tool vibration, and stiffness, mass and damping issues with emphasis in the machining dynamics; Then design processes of precision machine are discussed; And finally two case studies about design of a fast tool servo system and a 5-axis micro milling machine tool are given. Keywords: precision machines, machining dynamics, design, modelling |
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PID205496 |
A new technology platform for fully integrated polymer based micro optical fluidic systemsa: Center for Microtechnologies, Chemnitz University of Technology, Chemnitz, Germany b: CSEM Centre Suisse d'Electronique et de Microtechnique SA, Zurich, Switzerland c: Cardiff University, Cardiff, United Kingdom d :Comissariat à l'énergie atomique (CEA), Grenoble, France e: Zeptosens - a division of Bayer (Schweiz) AG, Witterswil, Switzerland f: Eurogentec S.A.,Seraing, Belgium g: Centre Hospitalier Regional de la Citadelle, Liège, Belgium AbstractThis paper describes a new technology platform for polymeric micro optical fluidic systems. The platform consists of active and passive optical and fluidic elements for a surface plasmon resonance (SPR) biosensor for the detection of proteins. The platform includes the integration of polymer light emitting diodes, polymer photodiodes as well as polymer based fluidic valves and pressure generation elements. Surface functionalization for micro optical and micro fluidic parts as well as advanced manufacturing methods are other important parts of the presented technology platform. Keywords: Lab-on-Chip, Point-of-Care, Micro Optics, Micro Fluidics, Surface Plasmon Resonance, polymer LED,B iosensor, Hydrogels, Microspheres, Micro Actuators, Polymer MEMS |
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PID193180 |
Market Forecasts for Roll-to-roll Electronics ManufacturingIDTechEx, Ltd. Far Field House, Albert Road, Stow-cum-Quy, Cambridge, UK AbstractThe significant developments in printed organic and molecular electronics will have a profound effect on the market for consumer and industrial products. By allowing the continuous production of functional electronic devices on roll-to-roll assembly lines, two fundamental changes are taking place in manufacturing. First, existing, costly< processes may be replaced by more efficient production methods enabling widespread development of lower cost electronics. Second, entirely new markets may emerge that were not feasible prior to these developments. Several of these markets and applications are described along with their significance in reinforcing knowledge driven manufacturing bases within the European Community. Keywords: Roll-to-Roll Electronics, Market Forecasts |
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PID202099 |
SME's Perspectives: 4M current capabilities and future requirementsIVAM Microtechnology Network, Dortmund, Germany AbstractThe participation of small and medium sized enterprises (SME) in research and development is essential given their role in promoting innovation in this field. This is especially true in the field of microtechnology. The paper looks at different surveys and studies to analyse the potential for growth of SME in Europe especially in the 4M technologies. The bottom up survey within IVAM membership gives an overview on the technologies and application fields of European SME. These results are reflected in relation to the market reports of Yole Developpement and the NEXUS III report. Keywords: SME, Europe, global competitiveness |
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A roadmapping study in Multi-Material Micro Manufacturea Manufacturing Engineering Centre, Cardiff University, Cardiff CF10 3XQ, UK AbstractThis paper reports findings from a roadmapping study conducted by the FP6 Network of Excellence in Multi-Material Micro Manufacture (4M). The main aim of this study is to help inform European research and industry about current trends and application requirements in the development of Micro- and Nano-manufacturing Technologies (MNT) for the batch-manufacture of micro- components and devices. The results are based on a roadmapping workshop attended by 30 senior researchers and parallel questionnaires administered to 38 associated industrialists. Primary application areas addressed were micro-fluidics, micro-sensors & actuators, and micro-optics, while the technologies covered were surface modification and structuring processes, energy assisted and mechanical processes, and replication processes. Reported results include the main market sectors for these three application areas as perceived by the industrialists together with the main application requirements for developing/manufacturing micro products and the important current and future micro manufacturing technologies. Generic and specific conclusions are derived about the existing trends in developing micro technologies and their applications. Keywords: micro manufacture, multi-material, roadmap |
| PID183452 |
Replication of micrometric pattern by hot embossing of silica based feedstock AbstractThe CEA is developing a new forming technique derived from the hot embossing of polymers. This technique consists in replacing the polymer by a feedstock composed on binders and inorganic nanopowders. The process consists in three stages that are forming/pressing, debinding and sintering, similarly to the micro Powder Injection molding. This process has been optimized for the replications of micrometric patterns. This work has led to the development of a feedstock composed of water-soluble binder and nanometric fumed silica. It was possible to replicate gratings of ~1 micron after sintering. The replication of sub-micronic plots is not possible at this stage. It is expected that the use of smaller particle size could allow reaching this objective. Keywords: hot embossing, gratings, silica |
| PID189090 |
Force fields with one stable equilibrium for micropart 2D manipulation
AbstractThis paper proposes an approach for structuring a two dimensional (2D) force field with just one stable equilibrium at the desired location for the manipulation of microparts without sensing. The derived force field induces a unique stable equilibrium for any convex or non-convex polygonal micropart on the plane with arbitrary shape and size, where the equilibrium pose is the desired location of the micropart. Extensive simulations show the efficiency of the proposed method in the formulation of the force fields for 2D manipulation of microparts. Keywords: stable equilibrium, force field, micropart manipulation |
| PID189540 |
Off-Axis Machining of NURBS Freeform Surfaces by Fast Tool Servo Systems
AbstractThe manufacturing of optical components with complex geometries like freeform surfaces is getting more and more important. Mass production of these optics is enabled by replication methods like injection moulding. For the machining of the required mould inserts with freeform geometries ultraprecision technologies like Fast Tool Servo turning can be applied to achieve the appropriate optical surface quality. For the mathematical description of freeform surfaces NURBS (Non Uniform Rational Basis Splines) are highly applicable. To avoid interpolation errors and to create set points with a continuous and smooth path of motion a trajectory generator directly based on NURBS data has been developed for Fast Tool Servo assisted turning [1], which evaluates the NURBS surface in each position control cycle. An approach of increasing the efficiency of manufacturing freeform surfaces is the off-axis machining of multiple workpieces at the same time. The paper presents the different process steps in simulation and off-axis machining of freeform surfaces using Fast Tool Servo assisted turning in conjunction with NURBS based data processing. Keywords: Ultraprecision Machining, Fast Tool Servo System, Freeform Surfaces (NURBS), Off-Axis Turning |
| PID189565 |
Automated tool exchange for ultraprecision diamond milling and turning applications
AbstractActive tool wear control is a crucial factor for fulfilling the high shape and surface requirements in the large area ultraprecision diamond surface structuring of optical components. The Fraunhofer IPT has developed opto-mechanical setups for a fully automated in situ tool characterisation and a reproducible tool exchange. The systems embody a submicron accuracy for both, the machining of planar masters for replication by means of planing and fly-cutting operation as well as for the turning of large rollers for embossing applications. Keywords: diamond turning, ultra-precision machines, automated referencing and tool exchange, tool wear control |
| PID189658 |
Polymer Based Multifunctional 3D-Packages for Microsystems
AbstractMultifunctional 3D-packages can be fabricated with nearly any geometry using injection moulding. 3D line patterning can be performed on injection moulded parts with very flexible laser techniques. Finest line pitches can be realized with subtractive patterning as well as with additive laser direct structuring (LDS). For mounting of SMD and bare dies different assembly techniques can be used. Keywords: MID, laser patterning, assembly, bare die, SMD |
| PID189798 |
Laser transmission welding of micro plastics partsE. Haberstroh, W.-M. Hoffmann AbstractOnly few welding processes for plastics meet the special demands of microtechnology. Laser transmission welding has distinctive advantages like low mechanical and thermal load of the joining parts. Thus the laser is a joining tool which is particularly suitable for the welding of micro plastics parts. Contour welding is a process variant of laser transmission welding enabling the welding of complex and even three-dimensional weld contours. In addition to that, this is a very flexible process which can be easily adapted to changing part geometries. So far it is only applied for welding plastics parts of macroscopic scale in the industrial practice. Recent research at the Institute of Plastics Processing in Aachen shows that it is also possible to use this process to weld filigrane micro parts. Thus another promising welding process has proven its suitability for the microtechnology. Welding trials with different thermoplastics show, however, that there are big differences in the material behaviour that make some platics more suitable than others for the contour welding in microtechnology. Keywords: laser transmission welding, contour welding, tear-out force, weld seam morphology |
| PID189909 |
Prototyping of multilayer waveguides with V-grooves in COC/Topas®
a MIC - Department of Micro and Nanotechnology, Technical University of Denmark, b HSG-IMIT, Institute for Micromachining and Information Technology,Villingen-Schwenningen, Germany c IMTEK - University of Freiburg, Laboratory for MEMS Applications, AbstractA number of fast and low-cost methods are used for prototyping of optical waveguides in the cyclic olefin copolymer Topas®. This polymer has a number of advantages compared to polymers traditionally used for micro systems. The advantages include good chemical resistance, good optical properties, and low water absorption, making it well-suited for lab-on-a-chip systems. Using micro milling, spin coating, and thermal bonding, and exploiting the different refractive indices of different grades of Topas®, waveguides with a width and heigth of 130 μm are created. 45° V-grooves at both ends of the waveguides are used for coupling light in and out of the waveguides, using the principle of total internal reflection. In this manner light can be coupled into the waveguides perpendicularly from above or below the structure, depending on the groove orientation. This coupling scheme has a large potential for rotating microfluidic system, the so-called lab-on-a-disk systems. Keywords: COC/Topas®, micro milling, waveguides, prototyping, V-grooves |
| PID189953 |
An integrated solenoid-type inductor with Fe-based soft magnetic coreChong Lei a, Yong Zhou a, Wen Ding a, Xiao-Yu Gao a, Ying Cao a, Hyung Choi b,Jonghwa Won b b Samsung Advanced Institute of Technology (SAIT), Samsung Electronics Co., Ltd., 416 Maetan-Dong, AbstractThis paper reports on a technological process that combines copper as conductor, soft FeCuNbCrSiB magnetic thin film prepared by magnetron sputtering as magnetic core and polyimide as the insulation material to complete a solenoid-type inductor with high inductance and high quality factor. The shape of the magnetic core scheme is rectangular, and the size of the inductor is 4 mm × 4 mm × 0.084 mm. The results show that the fabricated solenoid-type inductor has high inductance and high quality factor in the frequency range of 1-20 MHz, the inductance is 1.19 μH at a frequency of 1 MHz and the maximum quality factor is around 4.5 with an Keywords: high inductance, high quality factor, Fe-based magnetic thin film, solenoid-type inductor |
| PID189972 |
In-process assembly of micro metal inserts in a polymer matrix
Department of Manufacturing Engineering and Management, Technical University of Denmark, AbstractNew functionalities and smaller dimensions of micro products can be achieved by means of a higher degree of integration of both materials and components. Smart micro assembly techniques (such as on-the-machine assembly) together with hybrid structures (as metal inserts in polymer matrix) are suitable solutions to manufacture new micro products with several integrated functionalities, reduced number of components and assembly phases, as well as the possibility to be replicated in a high number of specimens. Innovative manufacturing systems, as well as new design rules and testing methodologies, have to be established in order to be able to develop new and more integrated micro products. In this paper a method for testing the bonding between micro thickened metal inserts and the polymer matrix they are moulded in is presented. A specific demonstrator has been manufactured by means of a hot embossing-like process which allows fast developing time and the possibility of batch process. Different levels of surface roughness and metal insert thickness were applied in a systematic design of experiments. The results show a strong influence of surface texture on bonding strength. The testing procedure assists the designer in giving data to be used when dimensioning micro products involving integrated metal parts in a polymer product. Keywords: bond strength testing, micro metal inserts, polymer hybrid structures, in-process assembly |
| PID190091 |
Low Temperature Adhesive Bonding in MEMS
AbstractA new concept for adhesive bonding of components with dimensions less than 300 μm in complex 3D structures is presented in this paper. Two different kinds of adhesives - polyurethane adhesive foil and polyethylene hot melt glue - were applied to the basic substrate by different techniques. The focused stream of hot gas directed to the substrate softens glue which had been applied as a solid. Afterwards, micro-parts were embossed in the softened glue, or covered and shielded by it. After cooling down at room temperature, a rigid and compact bond was formed. The parameters which induce the heat transfer and the process performance generally are considered through various experiments. The advantages of this new approach are compact system which can be easily integrated in existing production lines, low capital costs, partial reversibility, applicability to many material combinations, localized heating with reduced thermal stresses, etc. In order to confirm the advantages of proposed bonding technique, a single mode glass optical fiber (core diameter 9 μm; cladding diameter 125 μm) was positioned in V-grooves to achieve requested alignment and positioning precision. V- grooves were made by chemical etching of silicon in the “111” plane. Bonding glass to glass was also successfully demonstrated. Keywords: adhesives, low temperature bonding, hot gas stream |
| PID190112 |
Manufacture of recessed rotating microelectrodes for mass transport investigations in the LIGA process
AbstractThe enhancement of the knowledge of mass transport during the different manufacturing stages of high aspect ratio microstructures is important for further progress in the LIGA technology. The information about mass transport characteristics is essential in order to find the optimal processing parameters for the development and the electroforming. A new construction and fabrication method for recessed rotating microelectrodes (RRME) for mass transport investigations in micro technology is presented. The manufacturing of these electrodes based on the LIGA process is described. This technology was tested in practice, its deficiencies were discovered and a new improved technology was presented. The improvement includes a substitution of electrochemical gold deposition to vapor deposition and using an alternative glue, which provides sufficient PMMA to gold adhesion. The fabricated RRMEs were tested in electrochemical ferro/ferricyanide system and the first test results are reported. It has been shown that RRME, produced by improved technology, meet qualifying requirements and can be used for mass transfer investigations in micro technology Keywords: fabrication technology, recessed rotating microelectrodes (RRME), LIGA process |
| PID190360 |
Fabrication of a solenoid-type inductor with electroplated NiFe magnetic Core by MEMS
a National Key Laboratory of Nano/Micro Fabrication Technology, Key Laboratory for Thin Film and Microfabrication of Ministry of Education, Institute of Micro and Nano Science & Technology, Shanghai Jiao Tong b Samsung Advanced Institute of Technology (SAIT), Samsung Electronics Co., Ltd., 416 Maetan-Dong, Yeongtong-Gu, Suwon, Kyungki-Do 442-742, Korea AbstractA solenoid-type inductor was fabricated by MEMS (Microelectromechanical Systems) technique. NiFe film was electroplated as the magnetic core, and polyimide with a low relative permittivity was used as the insulation material. In the fabrication process, UV-LIGA, dry etching, fine polishing and electroplating technique have been adopted to achieve high performance of the solenoid-type inductor. The inductor was in size of 3.9 mm × 2.66 mm × 80 μm with coil width of 20 μm, space of 35 μm and aspect ratio of approximately 4:1. The inductance was 1.973 μH at a frequency of 1 MHz, and the maximum quality factor was 1.52 at a frequency of 2.14 MHz with an inductance of 1.82 μH, which is attractive for the applications of micro DC/DC converter. Keywords: Inductance, NiFe magnetic core, MEMS, solenoid-type inductors, quality factor |
| PID190369 |
Fabrication of a solenoid-type inductor with electroplated NiFe magnetic Core by MEMSChong Lei a, Wen Ding a, Yong Zhou a, Xiao-Yu Gao a, Hyung Choi b, Jonghwa Won b b Samsung Advanced Institute of Technology (SAIT), Samsung Electronics Co., Ltd., 416 Maetan-Dong, AbstractA solenoid-type inductor was fabricated by MEMS (Microelectromechanical Systems) technique. NiFe film was electroplated as the magnetic core, and polyimide with a low relative permittivity was used as the insulation material. In the fabrication process, UV-LIGA, dry etching, fine polishing and electroplating technique have been adopted to achieve high performance of the solenoid-type inductor. The inductor was in size of 3.9 mm × 2.66 mm × 80 μm with coil width of 20 μm, space of 35 μm and aspect ratio of approximately 4:1. The inductance was 1.973 μH at a frequency of 1 MHz, and the maximum quality factor was 1.52 at a frequency of 2.14 MHz with an inductance of 1.82 μH, which is attractive for the applications of micro DC/DC converter. Keywords: Inductance, NiFe magnetic core, MEMS, solenoid-type inductors, quality factor |
| PID190376 |
Surface micromachined three-dimentional solenoid-type inductorDong-Ming Fang, Yong Zhou, Wen Ding, Xi-Ning Wang, Xiao-Lin Zhao AbstractMiniaturized integrated inductor of high performance is very important in mobile communications and microwave integrated circuits. Existing on-chip spiral inductors based on conventional planar integrated-circuit fabrication technology suffer from substrate loss and parasitics, and have relatively large area. In this paper, We present the design, fabrication, and performance of surface micromachined on-chip three-dimentional (3-D) aircore solenoid microinductors. The fabricated microinductors are characterized at high frequencies from Sparameter measurements. The resulting 7-turn air-core solenoid inductors have inductances between 1.03 to 1.81 nH, peak quality (Q) factors between 19.1 to 38.0 at peak-Q frequencies between 4.4 to 6.0 GHz, and selfresonant frequencies between 10.5 and 13.0 GHz. Keywords: Inductor, RF MEMS, quality factor, 3-D |
| PID194308 |
Development of a MID LED housingR. M. de Zwart, R. A. Tacken, P.J. Bolt AbstractThe development of microdevices would be well served by integration of electronic connects into 3D packaging. A number of technologies have been proposed in which conductive paths are created on polymer structures, of which MID (Molded Interconnect Device) technology excels in 3-dimensional flexibility. In this study, the feasibility of manufacturing a three-colour light emitting diode housing with MID technology is demonstrated. Requirements with respect to connection to the housing included absence of wire bonding and SMT relflow solderability. Two technologies were investigated: (i) two-component molding using pre-catalysed LCP and (ii) SKW process with polyamide 4,6. In both processes successive electroless copper deposition was used followed by nickel and gold coating to obtain good olderability. In processing the pre-catalysed LCP the critical step appeared to be the initial electroless copper deposition which requires tight control to obtain the metallization selectivity required. In the SKW process proper handling of parts in the catalytic activation step between molding the first and second shot is the main factor influencing yield and quality. A fairly large number of products were made with both technologies on lab scale. The finished housings were assembled on a PCB in a reflow solder process and performance of the products was evaluated positively with respect to mechanical integrity as well as electrical behaviour. Keywords: molded interconnect devices, metallization, integrated electronics, two-component molding, LED |
| PID197126 |
Micropart manipulation by electrical fields for highly parallel batch assembly
* Chip Interconnection Technologies, Fraunhofer IZM, 13355 Berlin, Germany AbstractThis paper depicts the concept of micro part manipulation by electrical fields to achieve a high precision, highly parallel batch assembly of components required to put Microsystems together. The concept of orienting microparts in 3D as well as precision alignment on a temporary precision carrier substrate is described and simulations are performed to identify an optimal configuration of the electrical field. In order to move the microparts, they are included in a liquid droplet of high dielectric constant, allowing for fast movement and easy control. The concept implementation idea is briefly described and the required electrode structure is depicted. Keywords: MEMS, 3D manipulation, force fields, electrowetting |
| PID197636 |
Design and Manufacturing of Micro Heaters for Gas Sensors
1 IVF- Industrial Research and Development Corporation; Argongatan 30, S431 53 Molndal, Sweden, AbstractThe paper presents the design and manufacturing steps of micro heaters, built on ceramic suspended membranes for gas sensor applications. The micro heaters are designed and fabricated by combining laser milling techniques, and conductive ceramic technology. Trenches are created in the ceramic substrate in order to define the geometry of the heater using laser processing of the substrate. The heater is completed by filling the trenches with conductive ceramic paste and then baking to remove the solvent from the paste. The final step involves releasing the membrane by laser milling, enabling it to be suspended on four bridges, to minimise the dissipation of the heat in the substrate. The temperature of the heater element was measured with a heat camera from FLIR 40 system comparing the case of the heater positioned on top of a released membrane and that of the non-released membrane. The simulation of the heater build on top of a released membrane was compared with the heater measurements. Keywords: Micro heaters, gas sensor |
| PID197641 |
Developments in Micro Ultrasonic Machining (MUSM)J.J. Boy*+, M. Aiguillé**, A. Boulouize**, C. Khan-Malek*** * FEMTO-ST / LCEP - 26 chemin de l'Epitaphe - 25000 BESANCON - France AbstractUltrasonic machining (USM) presents a particular interest for the cutting of non-conductive, brittle materials such as ceramics, glasses or fused silica and quartz crystal. Unlike other non-traditional processes such Electrical Discharge Machining (EDM and micro-EDM, adapted to conductive materials), laser ablation or wet chemical etching, USM does not thermally damage the workpiece and does not create significant levels of stresses. Production of complex 3-D shapes with a volume of a few cubic millimeters is presented. Keywords: Ultrasonic machining, micro technology, aspect ratio, tool wear, PZT. |
| PID199972 |
The effects of material microstructure in micro-millingK. Popov a, S. Dimov a, D. T. Pham a, R. Minev a, A. Rosochowski b, L. Olejnik c, M. Richert d a Manufacturing Engineering Centre, Cardiff University, Cardiff, UK, AbstractMicro-milling is one of the technologies that is currently widely used for the production of micro-components and tooling inserts. To improve the quality and surface finish of machined microstructures the factors affecting the process dynamic stability should be studied systematically. This paper investigates the machining response of a metallurgically and mechanically modified material. The results of micro-milling workpieces of an Al 5000 series alloy with different grain microstructure are reported. In particular, the machining response of three Al 5083 workpieces whose microstructure was modified through a severe plastic deformation was studied when milling thin features in microcomponents. The effects of the material microstructure on the resulting part quality and surface integrity are discussed and conclusions made about its importance in micro-milling. The investigation has shown that through a refinement of material microstructure it is possible to improve significantly the surface integrity of the micro-components and tooling cavities produced by micro-milling. Keywords: micro-milling, material microstructure, grain size effects |
| PID200144 |
Laser Micro-milling of Ceramics, Dielectrics and Metals using nanosecond and picosecond lasers
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| PID207178 |
Dimensional tolerances of micro precision parts made by ceramic injection moulding
AbstractThe aim of the study is to analyse the dimensional variation in ceramic injection moulding of micro precision parts made of zirconia ceramics in order to improve the quality of the injection-moulded parts and to reduce costly reworking of the sintered parts. Dimensional variation and surface quality of injection- moulded single-mode ferrules in the green and sintered state were measured with high precision in the sub-micrometre range. The influence of the process parameters on dimensional tolerances and surface quality of the parts was analysed. Furthermore, the dimensional tolerances and surface quality of the mould cavity used were measured and compared with those of the moulded parts. The results show that process parameters in injection moulding strongly influence the absolute dimensions as well as the dimensional scatter of the green compacts and sintered parts. The coefficient of variation of the outer diameter of the sintered ferrules (nominal value 2.5 mm) was between 0.2% and 0.3%. Furthermore, the injection-moulded green compacts showed shape deviations which could not be explained by the shape tolerance of the mould insert. Keywords: PIM, CIM, micro precision ceramic injection moulding, optical ferrule, zirconia |
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PID161133 |
Fiber optic temperature sensor based on spectral transmitivity of CdTe
a Institute of Sensor and Actuator Systems, Vienna University of Technology, Vienna 1040, Austria AbstractA fiber optic sensor for measurement of temperature in an environment with strong electromagnetic interferences is presented. The method is based on the change of energy gap of single crystal CdTe with temperature. The spectral transmission of sensing crystal is detected by a special spectrometric arrangement using a diffraction grating and a linear CCD sensor. The obtained measurement uncertainty is lower then ±1ºC, in the measuring range from 15ºC to 100ºC, with the data rate of several hertz. Keywords temperature measurement, fiber optic sensor, CdTe, spectrometer |
| PID182320 |
Mechanical testing of laser welded micro seams
AbstractIn a previous work, a low power diode laser has been presented, which is capable of creating laser welded seams as narrow as 10 μm in polymers. The ability to produce narrow seams makes this low power diode laser suitable for perimeter welding of micro fluidic channels in Lab On a Chip (LOC) systems. Perimeter welding is useful when bonding polymeric LOC systems since clogging of the micro channels is prevented during the bonding procedure. In the present work a new mechanical test method is put forward that tests the mechanical strength and homogeneity of a laser welded micro seam, both of which is important when a micro seam is used to bond the lid in a LOC. The test is a pressure test, where the weld seam is subjected to the stress that arises from an isostatic pressure in a cavity that is defined by two pieces of polymer and the weld seam in question. The paper presents the experimental work together with mechanical finite element simulations, both of which show how the mechanical test results are affected by the width of the laser welded micro seam. Among the results the yield pressure-seam width relationship is shown to have a contra intuitive behavior. Instead of having an ever decreasing yield pressure for decreasing seam widths, a local minimum in this relationship is found. Keywords Mechanical testing, micro welding, Lab on a chip, micro fluidics |
| PID187849 |
Reactive magnetron sputtering deposited ITO thin films : influence of O2 admixture on microstructure and optical propertiesC. Secouarda,b, C. Ducros a, P. Roca i Cabarrocas b, S. Noël c, F. Sanchette a a CEA Grenoble, Laboratoire des Technologies des Surfaces, 17 rue des Martyrs 38054 Grenoble CEDEX, France AbstractIndium-tin oxide (ITO) thin films have been deposited onto glass substrates by reactive magnetron sputtering. Effects of O2 content in Ar/O2 gas mixture on coatings properties were investigated. The structure was analysed by X-ray diffraction. In the region between 0 and 8 O2 vol.% in the gas mixture the crystallisation is improved and the lattice is expanded with increasing oxygen flow rates because of the incorporation of the overflowing oxygen. Above 8 O2 vol.% in the gas mixture the lattice is shrunk and the crystallinity is lowered. The crystallites size decreases with increasing oxygen flow rate after reaching a maximum at 4 O2 vol.% in the gas mixture. In fact, the excess oxygen is bound to be segregated to the grain boundaries preventing the grain growth and relaxing the lattice. The optical transmittance of the films was determined using a spectrophotometer. The transparency improves with increasing oxygen flow rates. The filling of oxygen vacancies and the deactivation of Sn donors both explain the red-shift in the UV region and the great increase of the transmittance in the near Keywords indium tin oxide, reactive magnetron sputtering, X-ray diffraction, transmittance |
| PID189204 |
Comparison of the control of laser striation on lamellar cast iron with various techniques
AbstractAfter engraving specific grooves by means of a laser Nd:YAG, three measurement techniques have been used in order to control the shape and geometry of the grooves. Different types of grooves have been studied. They are defined by their profiles and their spatial repartition. The first characteristic is the profile. Four cross section geometries have been selected: hemispherical, rectangular, trapezoidal and triangular. The second characteristic is the spatial distribution. The grooves are classified in two categories: continuous and discontinuous lines with a specific pattern for each one. The engraved material is lamellar cast iron which is a heterogeneous material. Consequently, the conditions of engraving are more difficult to define. Thus, an accurate metrology is the key point to adjust the laser machining in order to obtain the desired grooves. Three measuring techniques have been used to control one or more characteristics of the grooves like dimensions, distribution or profile. These techniques are: roughness profilometry, scanning electronic microscope and non contacting optical imaging. Combining information coming from those techniques, we lead to a better control of the geometry of the engraved surfaces. Keywords roughness profilometer, scanning electronic microscope, non contacting measurement, laser machining. |
| PID189390 |
Measurement and characterisation of the microtopography in the contact area between workpiece and tool in microforming
AbstractIn metal forming processes, the forming load is transmitted from the tool to the workpiece only by a certain fraction of the nominal contact area. According to the mechanical-rheological model these fractions are mainly the real contact area (RCA) and the so-called closed lubricant pockets (CLP). As the number of these contact areas (RCA and CLP) is reduced drastically in micro forming processes due to small part dimensions and approximately scale invariant surface topographies, their influence on the tribological conditions is increased significantly. Therefore, the knowledge about the real contact state in these areas in micro forming is much more important compared to conventional “macro” length scale. In the macro case, the real contact area is regarded as completely flattened during the forming process while the sub-topography which emerges on single asperities is not considered. In the present study, a test rig is introduced for the characterisation of the flattening behaviour of single asperities by in-situ observation and for the recording of the force-displacement characteristics. Additionally, a strategy for the evaluation of the sub-topography on single asperities is presented leading to an improved understanding of the tribological behaviour in micro forming processes. Thus, an improved simulative process design of micro forming processes is enabled. Keywords microforming, tribology, surface characterisation |
| PID189600 |
Micro particle sizing by using of ray optics Monte Carlo code
AbstractParticle characterization and identification methods are important for many scientific and technological applications ( manufacture and quality control of particulate materials, product research and developments, etc.) and give an invaluable tool in the frontier of sciences such as biotechnology, micro and nanotechnology. The present work concerns light scattering simulation as a specific particle sizing and characterization method. Ray optics Monte Carlo light scattering software is developed and applied for the study of micro particle polarization properties as a function of the particle size. A number of numerical experiments are performed and polarization phase functions for spherical, cubic and rounded cubic micro particles with various sizes and optical properties are presented. The proposed method is verified by a comparison between calculated and measured polarization phase functions for crystals of KBr. The developed software is relatively simple and powerful tool for micro particle sizing. It could be easy integrated in systems for particle characterization and identification. Keywords micro particle sizing, light scattering, polarization phase function, ray optics, Monte Carlo simulation |
| PID190218 |
Repeatability analysis of two methods for height measurements in the micrometer rangeC. Ferri a, E. Brousseau a, S. Dimov a, L. Mattsson b AbstractA precision study of two height measuring methods is carried out. The first method is based on a White Light Interferometer (WLI) and the second on a Co-ordinate Measuring Machine (CMM) equipped with an optical probe. The height measurements considered are in the range [150; 250] μm. Point and interval estimates of repeatability are reported in the paper. This study presents experimental evidence that, under repeatability conditions, the precision of the WLI method is about five times higher than that of the optical CMM method. Furthermore, the precision of WLI is constant over the investigated height range whereas a dependency of the CMM precision on the nominal dimensions is identified. For both methods a linear relationship is detected between the random error and the sequence in which the measurements are taken. Keywords Repeatability, White light interferometry, CMM |
| PID199127 |
Localizing micro-defects on rough metal surfaces.
AbstractIn this paper we present a study of reflectance measurements to a direct metrological problem. Our aim is to estimate progressive surface wear by detecting minute defect development in surface microtopography on Ra 0.7 μm rough stainless steel surfaces subject to mechanical wear from hard particle deposits on a metal bar. The investigation was carried out by using a CMOS digital camera with a macro objective, and was ought to demonstrate how surface scattering measurements can provide a viable alternative in circumstances where traditional roughness measurement techniques fail to deliver the expected results and, due to certain restraints, laboratory-type surface measurements are not applicable either. Our work is based upon measuring variations in the amount and direction of scattered light, reflected from the inspected surfaces, featuring microirregularities. We will show that it is possible to identify the extent of surface flaws by statistically evaluating the recorded brightness information. The developments in this paper can provide basis for a future quality control system devoted to on-line surface measurements. Keywords surface roughness, defect assessment, reflectance, light scattering, digital camera |
| PID185275 |
Forming and machining of the nano-crystalline alloysGy. Krállics a, M. Horváth b, J. Nyirő b a Department of Materials Science and Engineering, Budapest University of Technology and Economics, H-1521 Budapest, Bertalan L. u.7., Hungary AbstractEqual-Channel Angular Pressing (ECAP) is an effective tool for producing ultra fine grained materials. repeated application of ECAP, the rotation of the sample along the longitudinal axis of the billet allows to carry out different routes of deformation. The applied route has a strong influence on the texture, microstructure and mechanical behaviour of ECAP processed metals. In the present study ECAP was successfully applied to produce ultra fine-grained microstructure in a commercial Al-Mg-Si alloy (AI 6082). The mechanical investigations of the ECAP deformed specimens revealed that after 4 ECAP passes the material had a very high strength but a significantly decreased ductility. Further ECAP processing to 8 passes by route C increased ductility dramatically and strength slightly. This indicates that the anisotropy of the structure of ECAP deformed materials may play an important role in achieving good ductility. We made an ultra-precision manufacturing that we analyzed the changing of structure of nano-crystalline materials and the surface roughness for the effect of machining. After manufacturing we prepared an analysis with AFM (Atomic Force Microscope). The results provided that the quality of the ultra-precision finished surface of the processed sample improved dramatically after eight passes. Keywords: Equal channel angular pressing, high strength and ductility, nano-sized microstructure, surface quailty |
| PID189457 |
Modelling and design of GaN based piezoelectric MEMSC.R. Bowen a, D.W.E. Allsopp b, R. Stevens a, P.Shields c, W.N. Wang c a Materials Research Centre, Department of Mechanical Engineering, University of Bath, Bath, UK, BA2 7AY AbstractThe conditions encountered in aerospace, in automotive and many industrial applications present a challenge for semiconductor based sensor technologies. High temperatures (>180C) or ionising radiation inhibit the use of silicon transistors. This limits the scope for integrating silicon based sensors and MEMS with conventional electronics. The challenge of extreme environments requires a new approach. We examine here a solution based on GaN, a material with properties that offer wide ranging novel functionality and unexplored scope for integrating advanced sensor devices into single integrated systems for reliable operation in a wide range of extreme environments. Keywords: GaN, piezoelectric, MEMS, sensor, actuator |
| PID189543 |
Indirect Tooling Based on Micromilling, Electroforming and Selective EtchingP.T. Tang a, J. Fugl a, L. Uriarte b, G. Bissacco a & H.N. Hansen a a Dept. of Manufacturing Engineering and Management (IPL), Technical University of Denmark, Produktionstorvet, bldg. 427S, DK-2800 Kgs. Lyngby AbstractThe tool inserts used for injection moulding or hot-embossing of polymer micro-components, are the most important and expensive and crucial part of this important mass-production process. In this paper a new fabrication scheme is introduce, consisting of a combination of micro-milling, electroforming and selective etching. The basic concept is to exploit the benefit of true 3D-machining in a soft substrate such as aluminium with the excellent replication capabilities of nickel electroforming. The term indirect machining covers the fact that the master that is produced by machining a positive structure, i.e. the opposite of what is needed for the actual mould insert. Keywords: micromilling, electroforming, selective etching, tooling, injection moulding |
| PID189575 |
Systematic Interaction of Sedimentation and Electrical Field in Electrophoretic DepositionS. Bonnas a,b, J. Tabellion b, H.-J. Ritzhaupt-Kleissl a, J. Haußelt a,b a Institute for Materials Research III, Forschungszentrum Karlsruhe, 76021 Karlsruhe, Germany AbstractThe systematic interaction of sedimentation and electrical field in electrophoretic deposition allows the tailoring of specific properties of deposited green bodies. This technique permits a selective deposition of the nanosized fraction of conventional powders with broad or non-monomodal particle size distribution, thus making preceding classification obsolete. Potential applications are coatings with a very smooth surface or the replication of microstructures or moulds which are filled with nanosized particles and subsequently with coarser particles as support in one process step. Also graded structures can be fabricated with regard to particle size distribution, porosity and composition (e.g. zirconia toughened alumina). In this paper, the interaction of sedimentation and electrical field in electrophoretic deposition is described focussing on the characterisation of both processes, sedimentation and electrophoretic deposition. In addition the effectiveness of the combined process will be shown. Keywords: electrophoretic deposition, sedimentation, particle size distribution, zirconia |
| PID190004 |
Particle size dependent viscosity of polymer-silica-compositesT. Hanemann a,b, R. Heldele a, J. Hausselt a,b a Forschungszentrum Karlsruhe, Institut f. Materialforschung III, D-76021 Karlsruhe, Germany AbstractIn this paper the influence of micro- and nanosized particles on the flow behaviour of unsaturated polyester resinsilica-composites will be compared. Commercially available micro-sized quartz filler and different hydrophilic or hydrophobic nanosized Aerosils were investigated with respect to the change of the viscosity as well as the flow activation energy with filler load. Apart from particle size and specific surface area the polarity of the filler's surface has a strong impact on the resulting flow behaviour and the accessible maximum filler load. The dependence of the relative viscosity upon the filler load was described using different empirical approaches as established in thermoplastic or wax based feedstock systems containing porcelain, alumina or PZT. Keywords: Polymer-ceramic-composites, rheological properties, nanosized particles |
| PID190130 |
Micro EDM parameters optimisationS. Bigot a, J. Valentinčič b,c, O. Blatnik b, M. Junkar b a Manufacturing Engineering Centre, Cardiff University, Cardiff, UK, e-mail: bigots@cf.ac.uk AbstractElectrical discharge machining (EDM) is an important process in the field of micro machining. However, a number of issues remain to be solved in order to successfully implement it in an industrial environment. One of these issues is the processing time. This paper investigates the optimisation of machining parameters for rough and fine machining in micro EDM. In one case, the parameters are selected to achieve the highest material removal rate (MRR). In the other case, the best surface roughness is targeted. Some of the main difficulties linked with micro EDM are caused by the high wear occurring on the electrode. The study focuses on a specific combination of electrode and workpiece material and proposes a typical method for micro EDM process optimisation. Keywords: micro EDM, micromachining, roughing, finishing, micro holes and cavities |
| PID190199 |
Micro EDM parameters optimisationR. Jurischka a, A. Schoth a, C. Müller a, D. Thiebaud b, R. Gallera b, H. Reinecke a a Department of Microsystems Engineering IMTEK, Laboratory for Process Technology University of Freiburg, 79110 Freiburg, Germany AbstractToday, microfluidic devices are becoming more and more important in life science, chemical analytic, and medical areas. For these applications disposable and low cost articles are highly convenient. Polymers are ideally suited for these applications due to their material properties and their applicability for high volume production with high accuracy. In this study, we optimized the μEDM-milling technology to fabricate mold inserts made from steel, including microfluidic structures, with an excellent surface quality. The microfluidic structures have channel dimensions down to 18 μm, aspect ratios of up to 4 and a surface roughness Ra Keywords: micro replication, injection molding, microfluidic, EDM, milling, steel, tool |
| PID190199 |
Characterization of Molecularly Imprinted Polymers as Novel Materials for Biochemical SensorsNeda Haj Hosseini a,b, Cristina Rusu a , Anatol Krozer a, Sjoerd Haasl a, Kristina Reimhult a, Jan-Olof Lindgren a, Peter Enoksson b, Lei Ye c a Imego AB, Arvid Hedvallsbacke 4, 411 33 Göteborg, Sweden AbstractWe study the behavior of Molecularly Imprinted Polymers (MIP) as novel synthetic receptor layers in biochemical sensors. Electropolymerization was used as an easy to implement method for polymer deposition and integrated impedance spectroscopy to monitor MIP behavior towards target molecules. Contrary to what is reported in the literature we consider that it is neither easy nor reliable to attribute the impedance changes to target binding/elution. However, alternative and/or more precise characterization methods are needed to track nano-scale changes in MIPs. Thus we are developing an optical set-up for detection of static deflections on the micro-cantilevers as a result of surface stress induced by changes in MIPs. Using an optical set-up, changes in the deflection of MIP-covered microcantilevers when exposed to the target molecules could be measured. Keywords: Molecularly Imprinted Polymers, Impedance Spectroscopy, Micro-cantilevers, Biochemical sensors |
| PID191188 |
Structuring of phosphorescent pigments by two-step hot embossing for signaletic applicationsM. Sahli a,b,c, F. Legay a, C. Roques-Carmes a, C. Khan Malek b, J.C. Gelin c a Laboratoire de Microanalyse des Surfaces (LMS), ENSMM, 25030 Besançon cedex, France. AbstractThe hot embossing process is carried out in order to complement the panel of methodologies associated with the utilization of phosphorescent pigments for photoluminescent safety systems. The basic material, in compound form, is a strontium aluminate doped with Eu2+ and Dy3+ ions. Materials with these specific properties are protected from mechanical contact as well as from interactions with the environment, particularly atmospheric humidity to which these pigments are sensitive. Transparent structures with phosphorescent small-sized cavities were manufactured by a two-step hot embossing process developed for this application. The novelty of this work lies in applying the hot-embossing process to this new class of materials for safety applications. The modelling associated with this application allows the description of the velocity distribution in the various parts of the mould during the hot embossing process. Moreover it explains the interest of using sequential steps for testing signaletic applications. Keywords: Molecularly Imprinted Polymers, Impedance Spectroscopy, Micro-cantilevers, Biochemical sensors |
| PID191518 |
An Ultrathick SU-8 UV Lithographic Process and Sidewall CharacterizationK Jiang1, C-H Lee and P Jin Centre for MicroEnigineering and NanoTechnology, The University of Birmingham, Birmingham, U.K. B15 2TT AbstractThis paper presents a UV lithographic process for fabrication of ultrathick SU-8 micro structures and sidewall surface characterization. The UV lithographic process has enabled the thickness of the SU-8 structures to be increased from 240 um given in the datasheet to 1000 um, and thus massively increases the application range. In developing the UV lithographic process, the best softbake and UV exposure times have been searched and tested in experiments. The UV light transmission spectrum has been analyzed. Then the best results have been produced on the research basis. The straight sidewall and 40:1 aspect ratio SU-8 structure images are presented in the paper. As SU-8 microstructures are suitable for microfluidics and bio-compatible, the sidewall surface roughness is characterized using AFM. The roughness contour of the sidewall shows that the surface topography is similar throughout the depth. The average roughness Ra is 46.46 nm. Other surface parameters, such as Rq, Rp-p, Rpk and Rsk, are also obtained and analysed. The implication of the smooth surface roughness of SU-8 structures to their applications is discussed in terms of transmission efficiency, the changes in friction to flowing liquid in a microchannel and the changes in the surface tension and capillary effect. Keywords: Ultrathick SU-8, UV lithography, sidewall surface roughness, softbake |
| PID194624 |
Fabrication of nano-dimensional features in FOTURAN using focused ion beam technologyP.T. Docker, J Teng, P. D. Prewett, K. C. Jiang1 MicroEngineering and Nano technology Group, Department of Mechanical Engineering and Manufacturing University of Birmingham, Birmingham, B15 2TT, UK AbstractThis paper details the findings of work carried out to determine the feasibility of manufacturing nano-dimensional features in photoetchable glass (Foturan TM) using focused ion beam technology. To date the standard processing techniques for producing features (UV lithography and UV lasers) in this material are limited by grain structure giving minimum feature size typically 10 microns. Focused ion beam technology (FIB) offers two potential advantages: there is no additional processing such as wet etching in hydrofluoric acid and there is the potential to manufacture nanodimensional features, smaller than the micron scale which can be achieved using UV patterning with wet etch. This relies on the high resolution of the FIB system - Keywords: Photoetchable glass, Foturan, Nano-scale features, Focused ion beam patterning. |
| PID201294 |
Influence of the process parameters on themicrostructure of screenprinted Ba0.6Sr0.4TiO3 (BST60) thick-films on alumina-substratesF. Paul ∗, J.R. Binder, A. Berto, G. Link, H.-J. Ritzhaupt-Kleissl Forschungszentrum Karlsruhe, Institute for Materials Science III, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany AbstractThis article briefly discusses some aspects of the influence of process parameters on the microstructure of screenprinted BST60 thick-films on polycristalline alumina substrates. The focus of the experiments is directed toward the reduction of porosity by means of preparation without using sintering additives or composite techniques. The influence of paste composition, sintering temperature, cold isostatic compaction and microwave sintering on the morpholgy of the thick-films has been examined. The conclusion drawn from these results is, that the porosity of the films cannot be reduced by variation of paste composition or sintering temperature alone. Cold isostatic compaction of the green films leads to an improved homogeneity of the films, but not to a considerable reduction of porosity. Additional sintering by microwave might offer the possibility to reduce porosity of BST thick-films. Keywords: BST, thick-film, screen printing, ceramic powder, microstructure, microwave sintering |
| PID207929 |
Self-assembled nanostructured polymer films from concentrated solutions of block copolymersN. Didier a, P. Panine b a Ecole Nationale Supérieure de Physique de Grenoble, 38 402 St-Martin d'Hères, France AbstractWe are presenting in this paper a simple method to orient auto-assembling systems. We detail the production process of oriented nanostructured polymer films by shearing a concentrated solution of block copolymers. The most appropriate tool to simulate the applied strains during the film formation is a rheometer with a cone-plate geometry. We use the technique of Small Angle X-ray Scattering (SAXS) on the high brilliance beamline ID02 of the European Synchrotron Radiation Facility (ESRF) to analyse in situ the structure at large scale. By coupling on-line rheology with SAXS (Rheo-SAXS), we can determine simultaneously the structure and its stability associated with the shear rate. Hence, the solution is spread using a film applicator within the same mechanical strain deformation scheme. Once dried, films are observed by SAXS. Finally, a detailed analysis of orientation distribution function obtained from the SAXS diffusion pattern on each film provides a quantitative value of the level of alignment of the polymeric chains. Keywords: block copolymer, shearing, orientation, nanostructure. |
| PID172720 |
Micro-Injection Moulding: Factors Affecting the Replication Quality of Micro FeaturesB. Sha, S. Dimov, C. Griffiths and M. S. Packianather AbstractMicro-injection moulding is one of the key technologies for micro-manufacture because of its mass-production capability and relatively low component cost. The surface quality in replicating micro features is one of the most important process characteristics and constitutes a manufacturing constraint in applying injection moulding in a range of micro-engineering applications. This research investigates the effects of three processing and one geometric factor on the surface quality of micro features in three different polymer materials. In particular, the following factors are considered: barrel temperature, mould temperature, injection speed and placement density of micro features. In this investigation, the mould temperature was set in the conventional range. The study revealed that in general, increasing the barrel temperature, mould temperature and the injection speed improves the polymer melt fill in micro cavities. However, the effects of these factors on the process replication capabilities are not consistent for different polymer materials, and could be adverse in specific conditions. Varying the placement density of micro features does not affect the melt fills. Keywords: micro-injection moulding; micro features; surface quality. |
| PID182536 |
Laser polishingT. Dobrev, D. T. Pham and S. S. Dimov AbstractLaser milling with long pulses is generally associated with a high surface roughness, which prevents the broader use of this technology, especially in the manufacture of micro tools. In micro scale, achieving low surface roughness is very important, due to feature sizes. Laser polishing, also known as cleaning, is a novel technique for improving the surface quality of laser milled surfaces. It employs the same working principles as laser milling, but instead of having the target material in the focal point of the laser beam, an offset is introduced to the extent that there is not enough fluence for material removal. This paper reports on an investigation of the effects of laser polishing on two materials, industrial copper and stainless steel 316, used widely for the manufacture of micro cavities. The study provides an insight into the process behaviour during de-focused laser machining. Keywords: micro, laser, polishing, cleaning, surface roughness |
| PID186863 |
Size effects in the production of micro strip by the flat rolling of wireK. van Putten, R. Kopp, G. Hirt AbstractComparison between down scaled flat rolling experiments of thin round wire and numerical simulation of those experiments have shown that the production process of manufacturing micro strip out of thin round wire is influenced by size effects. Decreasing the wire diameter into the microscopic domain is accompanied by decreasing yield stresses of the wire and turned out to be the dominating size effect for low rolling reductions. For high rolling reductions an increase of friction becomes of major influence. The plane strain compression test is applied as an experimental simulation of the rolling process. It is also used for further investigation of the determined size effects. An experimental set-up has been built, that allows scaled experiments on small and miniaturised specimens maintaining geometric similarity. Micro structural effects, such as the Hall-Petch effect and effects on the evolution of the surface roughness have been determined with this plane strain compression set-up. Keywords: rolling, plane strain compression test, size effects, surface roughness, FEM simulation |
| PID188128 |
Manufacturing and characterization of water repellent surfacesA. De Grave, P. Botija, H.N. Hansen, P.T. Tang AbstractThe leaves of some natural plants show a micro structure giving them the capacity of being cleaned from any undesired particles by rainfall. Thorough studies of the physical laws that lay behind this phenomenon, known as the lotus effect, has been conducted throughout the years, in order to obtain a set of useful characteristics for such surfaces. The problem of adapting this behaviour to artificially roughened surfaces could be addressed by providing design criteria for water-repellent and self-cleaning surfaces. They could then be engineered according to the actual performances desired for them. Using an enhanced design criteria, the production of patterned micro structured surfaces following two different process chains is reported in the present paper. The first is a combination of laser manufacturing and hot embossing on polystyrene. To compare geometry and functionality, a non-silicon based lithography technique using copper laminated epoxy is described as a second approach. Hydrophobization of some surfaces was attempted. Results of characterisation are shown. Drop deposition tests are performed on the obtained surfaces following two methods. Keywords: water repellent surfaces, manufacturing processes chain, characterisation |
| PID189415 |
Challenging the sustainability of micro products developmentA. De Grave, S.I. Olsen AbstractEnvironmental aspects are one of the biggest concerns regarding the future of manufacturing and product development sustainability. Furthermore, micro products and micro technologies are often seen as the next big thing in terms of possible mass market trend and boom. Many questions are raised regarding the impact of size for recycling or environment. Indeed micro production is often seen as environmental friendly thanks to the small amount of material used. Such a statement can be misleading. In this article EcoDesign or Design for Environment (DFE) and Life Cycle Assessment (LCA) will be presented, together with some tools used in order to implement the concepts into design activities. Micro injection moulded components and MEMS are used as examples. Specificities of micro products will be investigated through a categorization in three levels: the end products, the whole production chain and the intermediate parts which can be in-process created. Possible future trends for micro products development scheme involving environmental concerns are given. Keywords: Sustainability, Design for Environment, Life Cycle Assessment |
| PID189427 |
Process parameter analysis on surface roughness and process forces in micro cuttingJ. Fleischera, G. Lanzaa, M. Schlipfa, J. Kotschenreuthera, J. Petersa AbstractHigh precision engineering has a great technological potential regarding the manufacturing of microtechnical products. Due to its flexibility and the possibility of producing complex three-dimensional geometries in a broad variety of different materials, micro cutting is of special importance in the already mentioned field. However, milling and turning in micro dimensions follow special rules what is caused by size-effects. Successful micro cutting depends on reliable processes and therefore on the knowledge about parameter adjustments and process characterization. By means of micro cutting test series and statistical analyses, effects and interactions of process parameter variations for work piece material, cutting edge radii, cutting speed, and depth of cut were identified and mathematically quantified. The results show a significant influence of the mentioned factors on the response variables. Thus, a linear model for specific cutting force and surface roughness is proposed. Furthermore, the findings are compared to the empirical cutting model of Victor-Kienzle in macro dimensions. Keywords: Micro Cutting, Process Characterization, Size Effects |
| PID189838 |
On the use of hot embossing for the reproduction of the surface topography of mould microreliefsM. Sahli a,b,c, C. Millot a, C. Roques-Carmes a , C. Khan Malek b and J.C.Gelin c AbstractThis article describes the quality of reproduction of microcavities structured into mould substrates which were filled by the imposed flow of amorphous polymeric materials. The rheology of the selected materials (cyclic olefin copolymer, COC) depends on the experimental parameters (temperature, pressure) used for the hot embossing process. To support the experimental data, the polymers were qualified by their melt flow index, flow index and consistency. The efficiency of the filling procedure into microcavities with smaller and smaller size is described using the potentialities of a customized Scanning Mechanical Microscope (SMM). Keywords: cyclic olefin copolymer (COC), rheology, viscosity, squeeze flow, hot embossing. |
| PID189952 |
Mechanical properties and bending behaviour of metal foilsA. Diehl, U. Engel, M. Geiger AbstractOngoing miniaturisation in various technical fields like electronics industry or micro systems technology is requesting precise forming processes for the production of small and thin components. Regarding these fields, thin metal foils are being used in micro-electro-mechanical systems, electronic components (e.g. leadframes) and in medical devices. As well as micro bulk metal forming processes, metal foils with thicknesses in the range of microns are subjected to the so called size effects. Previous investigations on various metal forming processes have shown the share of surface grains to be a decisive factor for the forming behaviour as it can be observed at micro foil forming. Besides this general valid size effect, every forming process inhibits specific size effects. In the case of bending processes large strain gradients are present, influencing the bending parameters and process accuracy (e.g. spring back). In the present paper, the mechanical properties and the bending behaviour of metal foils with thicknesses ranging from 25 μm to 500 μm are discussed in dependence of material properties, microstructure and foil thickness. Fundamental experiments are being performed, providing an experimental basis for future development of theoretical models describing strain gradient dependent forming behaviour of foil bending processes. Keywords: metal foils, mechanical properties, spring back |
| PID189973 |
Experimental study on the free-sintering process of a micro-porous HDPE membraneD.B. Trifonov a,, Y.E. Toshev b AbstractThe paper presents an investigation of the possibilities for optimization of the free-sintering process of a microporous HDPE membrane to be used mainly for fine bubble aeration. The HDPE membranes have priority significance in fine bubble operation in wastewater treatment applications. Precision molded porous plastic media have many applications in the industry, medicine and consumer products market. Of the other hand fine pore HDPE membranes, developed of special HD-PE material, provide excellent chemical and thermal properties for the most challenging environments. Various types of laboratory experimental tools for forming the micro-porous HDPE membranes at various process conditions were developed. The two-stage compression molding methods were used for forming the porous membranes. Approach for changing the process parameters for the sintering of the membranes after the compression molding was developed. Some experiments were accomplished using different variants of the technological equipment at different combinations of the sintering process parameters. Тhe possibilities for obtaining of micro-porous membranes with different pore size and minimum pressure loss of the compressed air flow, passing through the membrane were investigated. Keywords: micro-porous HDPE membrane, free-sintering, fine bubble aeration |
| PID189988 |
Hybrid tooling: a review of process chains for tooling microfabrication within 4MS. Azcarate 1, L. Uriarte 1, S. Bigot 2, P. Bolt 3, L. Staemmler 4, G. Tosello 5, S. Roth 6 and A. Schoth 7 AbstractThe current paper is based on the information gathered by the “Processing of Polymers” Division (Task 4.2 “Hybrid Tooling”) and “Processing of Metals” Division (Task 7.2 “Tooling”) within 4M Network activities. The aim of the task involves a systematic analysis of the partners' expertise in different technologies for processing tooling inserts for further replication in polymers. Firstly, the 4M partners current capabilities in individual tooling processes is briefly presented, and also the expected capabilities for year 2010 are analysed for each of the following processes: micromilling, micro-wire electrodischarge machining (ìWEDM), micro sinking electrodischarge machining (ìSEDM), laser micromachining, electrochemical micromilling (ìECM), and electrochemical milling with ultrashort pulses (ECF). Later the concept of 'hybrid tooling' as different process chains for tooling fabrication is introduced. Several examples of 'hybrid tooling' within 4M partners are presented. Considered materials are nickel for electroforming, stainless steel for ECF, and tool steel for the other processes. The paper results provide a global comparison between the previously mentioned processes, the current limitations of these technologies concerning feature sizes, surface finish, aspect ratios, etc. have been identified. The main conclusion drawn is the imperative requirement to combine individual processes ('hybrid tooling') to produce 3D free-form microshapes for tooling purposes. Keywords: Hybrid tooling, Process chain, Micromanufacturing |
| PID190076 |
Adapting ECF to steels used for micro mould insertsL. Staemmler a, K. Hofmann b, M.-H. Kim b, D. Warkentin a, H. Kücka b AbstractElectrochemical machining with ultra short voltage pulses (ECF) is an innovative technique to machine electrochemically active materials particularly very hard materials at micrometer feature size. Since the ECF technique is an electrochemical process neither mechanical forces nor thermal load are applied to workpiece or tool. For that reason ECF it is an ideal technique for the production of microstructures. Especially the use of steel as the workpiece material makes the ECF technique a promising technique for the production of micro mould inserts, since steel is resistant against the wear that occurs due to the injection process. Therefore the abilities and the limits of the ECF process for different types of tool steels are shown and the process parameters have been optimised. Acetic acid has been proven to be a suitable electrolyte for the ECF-process of tool steels. In this electrolyte tool steels like 1.2767 or 1.2312 can be processed with the ECF technique at a high quality. But in lowalloyed steels like 1.1730 only a poor quality can be obtained. Keywords: ECF, micro mould, steel |
| PID190114 |
Microfluidics on foilT. Veltena, H. Schucka, M. Richterb, G. Klinkb, K. Bockb, C. Khan Malekc, S. Polsterd, P. Bolte AbstractThe concept of microfluidics on foil opens up new opportunities for combining the advantages of having a flexible substrate with reel to reel processing which have the potential to be the basis for extremely cheap micro products. To reach this goal foil substrates must be combined with micro manufacturing technologies well adapted to these substrates. Some technologies are already available, some are subject of current research and some still have to be conceived. Here, technologies like reel to reel embossing, reel to reel laminating and laser ablation/cutting as well as laser welding will be discussed. A polymer electronics based alcohol sensor is presented and aspects of combining polymer (opto-)electronics and microfluidics on one foil based substrate will be discussed. Keywords: microfluidics, foil, reel to reel |
| PID190190 |
Application of SOI based sensors for MEMS wafer-level packagingFarzan Alavian Ghavanini 1, Cristina Rusu 2, Katrin Persson 2, Peter Enoksson 1 AbstractA method to evaluate MEMS wafer-level packaging by using sensors based on Silicon-on-Insulator (SOI) is developed. The SOI-MEMS technology has been used to create arrays of micromechanical stress and pressure sensors in the device layer of an SOI wafer. These sensors arrays will be used to evaluate the encapsulation characteristics of wafer-level packaging, by revealing the bonding-induced stress distribution as well as bonding quality. Mechanical resonance frequency and Q-factor of the sensors have been derived theoretically and were compared to the results of the Finite Element Modelling (FEM). The pressure sensor is designed to give Q-factor above 1000 at the pressures below 1 mbar and static capacitance of few pF. The resonance frequency of the stress sensor is designed for ca. 45 MPa as estimated for anodic bonding. The design, simulation and fabrication of the sensors are presented in this paper. Keywords: wafer level packaging, anodic bonding, resonators, stress sensor, pressure sensor, SOI |
| PID190246 |
Protective Coating of Zinc and Zinc Alloys for Industrial ApplicationsY. Toshev a, V. Mandova b, N. Boshkov a, D. Stoychev a, P. Petrova , N. Tsvetkova a, G. a Bulgarian Academy of Sciences(BAS) - Institutes of Mechanics, Physical Chemistry and Polymers; AbstractZinc and zinc-based electrogalvanized coatings have attracted remarkable interest because of the increasing demand for layers with better corrosion resistance. A new approach for improvement of the protective ability is the incorporation in the metal matrix of polymeric nanoparticles. The latter affect positively the protective properties of the nanocomposite coatings and result in increasing of their corrosion resistance in 5 % NaCl solution compared to the pure zinc and Zn-Co. The zinc coating process using the developed saturating mixtures excludes the phases of evaporation and condensation and the process is defined as hard-phase zinc coating. The hard phase zinc coating decreases the coating time 1, 5-2 times and powder dissipation with 20-25% compared to vapor-phase zinc coating. It does not require cooling the product together with the powder at the end of the process. The hard phase zinc coating has a high degree of automation and provides uniform coating of long-sized products and allows creating high-performing equipment. The prevention of the superficial roughness, during the hard phase zinc coating, leads to higher adhesion of varnishing coverings on the zinc-coated surface in comparison with vapor-phase zinc-coating. Keywords: RAS activities, zinc coating, corrosion protection, nano composite layers |
| PID191757 |
A Comparative Study of Three Technologies for Producing Castings with Micro/Meso-scale FeaturesJ-F. Charmeux a, R. Minev a, S. Dimov a, E. Minev a and U. Harrysson b AbstractThe paper investigates the capabilities of three different process chains for vacuum investment casting of parts with micro/meso-scale features. In particular, the capabilities of two layer-based manufacturing technologies, ThermoJet and PatternMaster, and a new direct shell printing technology developed by Fcubic are studied. The first two technologies create patterns out of a thermoplastic material that are suitable for casting parts utilising the classical two-stage lost-wax process while the 'Fcubic' process produces directly a casting tree in zirconia ceramics. The tests were carried out on a gravity casting machine on which overpressure/vacuum could be applied to facilitate the replication of components with micro/meso-scale features. Keywords: investment casting, 3D printing, metal micro-components. |
| PID192878 |
Influence of EDM machining on surface integrity of WC-CoMohammad Reza Shabgard, Atanas Ivanov, Andrew Rees Abstract:This paper studies the effects of ultrasonic vibration of the tool electrode on the surface integrity of tungsten carbide (WC-10%Co) in the electro-discharge machining (EDM) process. Scanning electron microscopy (SEM) with energy dispersive X-ray (EDX), optical microscopy, micro hardness testing and white light interferometery were employed in the investigation. The paper studies the composition, number and size of cracks on the surface layer, the topography of the machined surface and thickness of the defective layer. Keywords: Electro-discharge machining (EDM), Ultrasonic assisted EDM, Ultrasonic vibration of tool, Tungsten carbide (WC-Co), Surface integrity, Surface topography. |
| PID197592 |
Large Area Plastic Replication with Modular Molding ToolsM. Heckele 1, C. Mehne 2, R. Steger 3, P. Koltay 3, D. Warkentin 4 AbstractHot embossing of polymer microstructures has evolved over recent years from a simple lab technique to an established R&D technology. A multitude of technical applications demonstrate the high performance of this replication technique, which can provide more than first prototypes. Admittedly this technology is not recognized as a manufacturing process by industry. In this publication molding tool is presented which by its modular character can be easily integrated into existing hot embossing machines. Especially into a newly developed machine, which has been specially designed for the integration into a process chain. This modular molding includes a customized tool as well as a microstructured mold insert. The mold insert comprises discrete modules which can be changed for different applications or in case of partial damage. Finally the operator panels and equipment controls are based on standard PLC controls, which are known in manufacturing, and in this manner hot embossing optically becomes more trustworthy. The function and link-up of these components has been demonstrated using a “Dispensing Well Plate” with dimensions of 127.8 mm x 85.5 mm, to produce ambitious through hole nozzle components. With this continuous process chain it has been shown that hot embossing is ready for industrial implementation. Keywords: Replication, Polymer, Tool, Mold Insert, Hot Embossing, Dispensing W ell Plate, Through Holes |
| PID212833 |
Microforming of titanium - forming behaviour at elevated temperatureB. Eichenhüller, U. Engel AbstractTitanium is applied in a wide range of technical applications, especially when high strength in combination with light weight or corrosion resistance is demanded. Titanium is also a popular material for implants in the field of medical technology due to its specific properties like the superb biocompatibility, the elastic behaviour matching that of the human bone, the radiological transparency and the galvanic neutrality. For the production of these partly small-sized implants manufacturing methods with high accuracy and close tolerances are necessary. When forming processes are used to manufacture the miniaturised medical components the size effects occurring with miniaturisation have to be considered. The size effects are amongst others responsible for an increased scatter of process parameters and a reduced accuracy, thereby reducing the process stability. Also the limited formability of titanium and titanium alloys at room temperature is a drawback of forming microparts made of titanium. The main objective of the present study is to investigate the forming behaviour of titanium at microscale and enlarge the formability by means of forming at elevated temperature. Keywords: microforming, elevated temperature, titanium |
| PID189549 |
Mechanistic Modelling of the Micro- End Milling OperationL. Uriarte a, S. Azcarate a, A. Herrero a, L.N. Lopez de Lacalle b , A. Lamikizb AbstractThe paper describes a mechanistic model to predict the micro--milling cutting forces and to estimate the tool deflection and the real tool-path during the micro--milling process. Beginning from the “conventional” end milling cutting force model, several modifications are proposed to adapt it for the prediction of the micro--milling cutting forces, which is the aim of this research. A variety of end mill shapes are considered in the geometric part of the model. The paper presents the experimental validation using two-flute carbide micro-- end-mills with diameters from 0.1 to 0.4 mm. Finally, the consistency between the simulated and measured cutting force is shown as main conclusion. Keywords: Micro--milling, Modelling |
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| PID189823 | On Forces and Interactions at Small Distances in Micro and Nano Assembly Process D. Dantchev, K. Kostadinov Institute of Mechanics, Bulgarian Academy of Sciences, Acad. G. Bonchev St. Bl. 4, 1113 Sofia, Bulgaria AbstractWe present a short review on the quantum and the thermodynamic Casimir effect and show its practical relevance when considering objects placed away from each other at a distance below a micrometer range. Emphasis is made on the existing experimental verifications of the available theory as well as on the unresolved problems of the theory and the experiment. Everywhere where possible we try to point the potential practical application of the results described not only restricted to micro and nano assembly. Keywords: Casimir effect, micro & nano assembly, gripping force, micro fluidic interaction |
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| PID190020 |
Design procedure of planar compliant microgrippers with flexural jointsF. Székely, T. Szalay AbstractThe overall design scope of most microgrippers developed in recent years lacks a systematic mechanism design approach. Accordingly, the main objective of this investigation is to establish a new design concept in order to enhance the design scope of microgrippers. Using a systematic design procedure which particularly stresses planar compliant mechanisms, this study presents a two-fingered microgripper which has parallelogram mechanism. By the help of this construction the gripping surfaces stay in parallel position during its motion. The preliminary Finite Element (FEM) simulation results are in good agreement with the expected kinematic motion. Moreover, the stress analysis also points out that the relationship between the direction of driving force and orientation of deflected compliant joints is one of the crucial factors for designing the compliant microgripper mechanism. Hence, the mechanism design concept presented in this study can be integrated e.g. into the design of micro-scale actuating devices for Micro-Electro-Mechanical Systems (MEMS). Keywords: microgripper, compliant mechanism, laser cutting | |
| PID190054 |
Finite element analysis of the micro glass moulding processC. Brecher, M. Winterschladen, S. Lange, F. Klocke, G. Pongs, F. Wang AbstractThe manufacturing of optics is an important field of technology and will serve key-markets in the future. The research activities of the Transregional Collaborative Research Centre ”Process Chains for the Replication of Complex Optical Elements” SFB/TR4 of the Universities of Aachen, Bremen and Stillwater (USA) have the objective to lay the scientific foundations for a deterministic and economic mass production of optical and micro optical components with complex geometries, e.g. aspheric, non-rotational asymmetric or microstructured surfaces eventually superimposed on freeform geometries. The paper presents first principle simulation results of precision glass moulding for the analysis of micro form as well as nano surface quality manufacturing effects during the moulding process. Keywords: Finite Element Analysis, Glass Moulding, Precision Optics |
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| PID190231 |
Unified Approach For Functional Task Formulation In Domain Of Micro/Nano Handling Operations.K. Kostadinova, R. Kasperb, T. Tiankova, M. Al-Wahabb, D. Chakarova, D. Gotsevaa,c AbstractA unified approach for functional task formulation is developed that allows communication between user and team of mechatronic engineers developing the mechatronic handling devices for requested task function. All-important parameters are set for realization of mechanics and control of desired process for automation. 3D variants are modeled in SDS 2004+ and simulated, making interactive closed loop with the user and better communication between different research and industrial domains for achievement of good results. The possibilities of the developed iterative program for the task function formulation are illustrated with the results obtained for the case of micro/nano manipulations necessary for measurement of electrochemical impedance. Keywords: task formulation approach, interactive program, micro/nano handling operations. |
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| PID204355 |
Thermally induced stresses in an adhesively bonded multilayer structure with 30-micron thick film piezoelectric ceramic and metal componentsR.Jourdain and S.A.Wilson Abstract:In this study, the thermal stresses acting in a multilayer structure built up by successive bonding and machining processes are investigated. These arise mainly from the bonding process itself due to the wide mismatch in the coefficients of thermal expansion for the ceramic and metal components. Subsequent machining of the bonded ceramic down to 30 microns thickness leads to a redistribution of the internal stress which must be monitored closely as it influences both the structural integrity and the overall performance of the finished piezoelectric device. Previously reported analytical models are compared to new numerical simulations using either shell elements or two dimensional elements. High aspect-ratio, symmetric and non-symmetric structures are studied to show the changes in stress throughout the fabrication process. The finite element models allow detailed investigation of the stresses in all of the component parts and in the bonding layers. The influence of bond thickness is investigated in the range 0.5 to 10μm. This work shows that even at low bonding temperature the adhesive layer is under quite severe stress. This can be tuned by increasing the bond thickness to achieve high structural integrity and moreover the ceramic is engineered into compressive pre-stress suitable for high performance micro-actuators. Keywords: Bimorph; PZT; actuator; adhesive bonding; micro-fabrication; FEA; ultra-precision grinding, MEMS |
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| PID210079 |
Modelling and simulation of piezoelectric actuation and reliability of micropumpsMeiling Zhu a,*, Paul B. Kirby a, Martin Richter b, Yucel Congar b, Alexander Diehl c, Ralf Voelkl c AbstractModelling and simulation of a low cost micropump with promising mass production is described in this paper. The micropump has a very simple structure and therefore is very low cost effective. The pump consists of one plastic body, one metal diaphragm and three piezo PZT ceramics. The PZT ceramics glued on the metal diaphragm form three actuators and so the metal diaphragm bonded with the plastic body constitute three chambers, which are connected by interconnection channel in the plastic body. A 3D finite element analysis (FEA) model including an electromechanical coupled field simulation is set up and static analyses are preceded for different configuration under different applied voltage for understanding and optimization of the micropump performance. A significant dimensional design of piezo PZT actuators is obtained from simulation results. The ratio of the thicknesses of the piezo PZT ceramics to the metal diaphragm and the piezo in-plane dimension are suggested for obtaining a higher stroke for maximizing the pumping effect and lowering maximum stress in the metal diaphragm for concerning reliability issue. Keywords: Micropump; FEA; Piezoelectric actuators; Metal diaphragm |
| PID182168 |
Ultrasonic Plasticising for Micro Injection MouldingW. Michaeli, D. Opfermann AbstractUltrasonic energy is already used in the field of polymer welding. Research conducted at IKV shows a potential to use ultrasonic plasticising to generate melt for micro injection moulding. A test unit has been built to prove its potential as a plasticising unit. Based on these results the ultrasonic plasticising has been integrated into the micro injection moulding process. This leads to a significant reduction of the cycle time. Further research will focus on determining processing parameters for different materials and to further optimise the equipment. Keywords: micro injection moulding, plasticising, ultrasonics, melting |
| PID185132 |
The micro-machining evaluation of non-metallic materials - by a fluid guided laserPaul C. Snowdon a, David Wood a, Paul G. Maropoulos b AbstractThe waterjet-guided laser technique was originally developed to reduce the heat-affected zone near the cut, but many other advantages were observed due to the use of a waterjet rather than an assist-gas stream applied in classical laser cutting. This paper reports on the application of a fluid guided laser system, as an agile tool for the micro-machining of MEMS substrates, and materials associated with the expanding MEMS industry. An increasing number of applications require a more superior machining quality than can be achieved using standard/classical laser cutting. The materials machined during these evaluations include, gallium arsenide (GaAs) & silicon wafers, ceramic packaging (alumina) and kapton. An Nd:YAG laser operating at 1064 nm (infra red) and frequency doubled 532 nm (green) was employed for the machining of the various non-metallic materials. Keywords: Fluid guided laser, Laser Microjet®, MEMS, micro-machining |
| PID187815 |
Low Cost Capacitive Inclination Sensors based on selectively metallized polymerBenz Daniel a; Botzelmann Tim b; Kück Heinz a,b;Warkentin Daniel b AbstractWe report on an innovative low cost concept for micromechanical capacitive inclination sensors based on MIDtechnology (Moulded Interconnect Device) where three dimensional polymer devices are fabricated by injection moulding and covered by a structured metal layer using electroless plating and laser ablation. The sensor concept based upon an extended electrode design which combines two differential capacitors arrangements for a measurement range of ±180°. First MID-demonstrators were fabricated and characterized. The demonstrators show very promising properties. The sensors have a nice linear characteristic within ±45° and 45°-135° with a resolution of about 0,01° and a nonlinearity better than 0.5% FSO. At different angular rates a dynamical hysteresis occurs. The dynamical hysteresis is proportional to the rotational speed of the sensor. The temperature dependence is very low and almost linear. No failure occurred within first reliability tests of 100 sensors with thermal shock test and constant damp heat storage. Keywords: inclination sensor, moulded interconnect device, non-silicon material |
| PID189405 |
High resolution low cost optical angular resolverV. Mayer, D. Warkentin, H. Kück AbstractAt HSG-IMAT a new concept for a high resolution and low cost optical angular resolver is developed. The key element of the sensor concept is a disc with a high precision solid measure which is fabricated using the well known manufacturing process for compact discs (CD-Technology). Using this process, it is possible to fabricate a high precision solid measure in high quantities and at low manufacturing costs. To detect the angular position, a laser beam is focussed onto the solid measure. The beam is reflected from the backside of the disc onto a photo diode. The light intensity is modulated by diffractive microstructures of the solid measure. With a first experimental setup, the functional principle of the sensor was verified and the signal modulation with high accuracy was demonstrated. With a 10μm laser spot on the disc, diffractive microstructures with a width of 10μm (equivalent to 20μm pitch) are easy to detect. The experiments show that even fields smaller than 6μm can be detected with the setup. Incremental and absolute encoded systems can be realised with the sensor concept. For serial production of the sensor a 3D packaging in MID-Technology is proposed. angular resolver, rotary encoder, optical sensor, low cost, compact disc, laser |
| PID189847 |
Micro EDM: Accuracy of on-the-machine dressed electrodesA. Rees a, S.S. Dimov a, A. Ivanov a, A. Herrero b and L.G. Uriarte b AbstractThe introduction of a technique for on-the-machine electrode generation, utilising Wire Electrode Discharge Grinding (WEDG) has broadened the application area of the μEDM process. This paper studies the capabilities of the WEDG process for manufacturing micro electrodes. The accuracy of the electrodes produced on-the-machine is investigated and a solution is proposed to improve the process. The experimental results revealed the inherent limitations of the WEDG dressing process and the effects of machine accuracy on electrode quality. The study shows that by employing an optical verification system the accuracy of the dressing process could be improved significantly. Keywords: Micro EDM, micro-machining, EDM accuracy, WEDG, electrode dressing |
| PID189967 |
All Polymer Electrochemical SensorM.Bengtsson 1, G.Thrastardottir 1, T.S.Hansen 2, O.Geschke 1 AbstractThe paper describes the development of an all polymer electrochemical sensor in poly(3,4-ethylendioxythiophene) (PEDT) for detection of hydrogen peroxide (H2O2). To increase the sensitivity of PEDT to H2O2 Prussian blue (PB) has been added to the polymer to act as an catalyst for reduction of H2O2 . The sensitivity of the sensor with this addition was shown to increase up to 4 times. In order to use the sensor in a miniaturized flow format a flow cell was designed and tested with the same setup of polymer electrodes. Keywords: conductive polymers, electrochemical sensors, PEDT |
| PID190071 |
A Novel Protective Cover for MicrocomponentsAleksandra Cvetanovic, Andreja Cvetanovic, Daniela Andrijasevic, Ioanna Gioroudi, Werner Brenner AbstractThis paper presents a novel tool for assembly of micro particles in a SEM chamber. A new mechanismus, called Protective Cover for Microcomponents, which allows the positioning of the micro parts on the platform inside the chamber without gluing them on the platform is proposed. It is well known the vacuum pump, especially turbo pump, that makes a vacuum in the SEM chamber, has higher sensitivity to foreign object damage. That is the reason why the micro parts are glued on the disks in the platform of the SEM chamber. Otherwise, the grippers that have to pick, to lift and place the particle in a desired system (position, orientation) are very fragile and can not overcome the adhesive force of glue and separating the particle from the disk. Besides, for the automated assembly process it is very important that the particles stay on the exactly defined location and position. The showed system is standard and can be mounted without additional time, modification or expenses into the SEM chamber. It enables, on the one hand, easier manipulation of the micro parts, that need not to glue on the base and, on the other hand, opens the door for introduction more automation in the manipulation process in the SEM chamber by making a basis for modular assembly system. Therefore the future constructing of a modular holder which can correspond to different requirements of the assembly of numerous microsystems will also be reported .Need for standardisation in micro world becomes more and more articulate. With a higher level of standardisation, the degree of automation grows up, too. The |