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Cette thèse présente diverses applications de la photopolymérisation radicalaire dans les puces microfluidiques. Dans un premier temps, nous décrirons l'importance des modifications de surfaces des puces microfluidiques afin de conférer à la surface un caractère hydrophile et neutre. Nous présenterons une modification de surface par photopolymérisation radicalaire in-situ de polyacrylamide pour des puces d'une part en PDMS, sur lequel la longévité des modifications de surface est difficile à obtenir, et d'autre part sur le COC qui étant inerte chimiquement, est difficilement modifiable. Dans une autre application la photopolymérisation sera effectuée en volume et nous permettra d'intégrer très simplement des MEMS, in-situ dans le microcanal. L'intégration de réseaux de colonnes fonctionnalisées avec des protéines sera présentée, ainsi que l'implémentation de deux capteurs de flux. Un capteur de flux basé sur l'élongation d'une structure déformable s'est montré très performant en terme de large gamme de mesures, de sensibilité et de reproductibilité. Le deuxième capteur de flux est basé sur la rotation d'un objet autour d'un axe. Sa mesure est indépendante de la viscosité du fluide malgré ses moindres performances.

L'objectif de cette thèse est de concevoir et de réaliser une nouvelle génération de microphone MEMS monolithique de type électrodynamique, à base de bobines spirales planaires, réalisée en technologie standard complétée par un post process de micro-usinage en volume par la face avant. Après avoir décrire les différents procédés de fabrication des microsystèmes compatibles microélectroniques et récapituler l'état de l'art des différents principes de transduction des structures de microphones MEMS intégrés micro-usinés. Une modélisation électromagnétique détaillée est réalisée pour étudier le lien inductif entre les deux bobines, constituant le microphone, dans les différents modes de polarisation. Par la suite, une étude de la flexibilité et les constantes de raideur de la membrane suspendue a été menée. Cette analyse mécanique a pour but de concevoir un système de membrane souple qui a permis de placer la fréquence de résonance au milieu géométrique de la bande audible et d'avoir des amplitudes de déplacement suffisantes dans la plage linéaire. Ensuite, une modélisation électro-acoustique est nécessaire pour proposer un modèle théorique équivalent du microphone et évaluer sa sensibilité. Cette modélisation nous a permis de distinguer entre deux types de microphone {i} à conversion en déplacement et contrôlé par compliance et {ii} à conversion en vitesse et contrôlé par résistance. La dernière étape de cette thèse était d'accomplir le dessin des masques et fabriquer le 1er prototype.

<p>The aim of this work has been to develop new knowledge about macromodelling of microsystems. Doing that, we have followed two different approaches for generating macromodels, namely model order reduction and lumped modelling. The latter is a rather mature method that has been widely recognized and used for a relatively long period of time. Model order reduction, on the other hand, is a relatively new area still in rapid development. Due to this, the parts considering reduced order modelling is strongly biased towards methodology and concepts, whereas parts on lumped modelling are biased towards systems and devices.</p><p>In the first part of this thesis, we focus on model order reduction. We introduce some approaches for reducing model order for linear systems, and we give an example related to squeeze-film damping. We then move on to investigate model order reduction of nonlinear systems, where we present and use the concept of invariant manifolds. While the concept of invariant manifolds is general, we utilize it for reducing models. An obvious advantage of using invariant manifold theory is that it offers a conceptually clear understanding of effects and behaviour of nonlinear system.</p><p>We exemplify and investigate the accuracy of one method for identifying invariant manifolds. The example is based on an industrialized dual-axis accelerometer.</p><p>A new geometrical interpretation of external forcing, relating to invariant manifolds, is presented. We show how this can be utilized to deal with external forcing in a manner consistent with the invariance property of the manifold. The interpretation also aids in reducing errors for reduce models.</p><p>We extend the asymptotic approach in a manner that makes it possible to create design-parameter sensitive models. We investigate an industrialized dual-axis accelerometer by means of the method and demonstrate capabilities of the method. We also discuss how manifolds for nonlinear dissipative systems can be found.</p><p>Focusing on lumped modelling, we analyse a microresonator. We also discuss the two analogies that can be used to build electrical equivalents of mechanical systems. It is shown how the f → V analogy, linking velocity to voltage, is the natural choice. General properties of lumped modelling are investigated using models with varying degrees of freedom.</p><p>Finally, we analyse an electromagnetic system, intended for levitating objects, and we demonstrate the scaling effects of the system. Furthermore, we prove the intrinsic stability of the system, although the floating disc will be slightly tilted. This is the first analysis done assessing the stability criterions of such a systems. The knowledge arising from the analysis gives strong indications on how such a system can be utilized, designed, and improved.</p>

In this paper, some critical issues and problems in the development of TiNi thin films were discussed, including preparation and characterization considerations, residual stress and adhesion, frequency improvement, fatigue and stability, as well as functionally graded or composite thin film design. Different types of MEMS applications were reviewed and the prospects for future advances in fabrication process and device development were discussed. / Singapore-MIT Alliance (SMA)

Datorn är ett viktigt verktyg i vår vardag. För rörelsehindrade kan datorn vara en förutsättning för att kunna fungera i vardagen. Datorn har som tekniskt hjälpmedel gett funktionshindrade större möjligheter till meningsfulla aktiviteter, såsom att på egen hand skriva, läsa och kommunicera. Samtidigt är det inte alltid funktionshindrade klarar av att använda vanliga datorer utan behöver alternativa inmatnings- och styrenheter. Målet med denna licentiatavhandling har varit att utveckla tekniker som ska stödja personer med rörelsebegränsningar. Främst har arbetet varit att utveckla alternativa tekniker för att kunna manövrera en dator. Viktiga aspekter i arbetet har varit att göra hjälpmedlen användarvänliga, möjliga att individanpassa, och att ta tillvara de tänkta användarnas synpunkter kring behov och önskemål. Vidare har inmatningsenheten utvärderats av användare och även tillämpats som ett rehabiliteringsverktyg för en mindre patientgrupp med nackskador, så kallade pisksnärtskador. Utöver dessa vetenskapliga mål har produktionsaspekterna varit viktiga. För att säkerställa att enheten ska kunna bli en produkt måste den kunna produceras och säljas till ett rimligt pris och detta måste beaktas under hela utvecklingsprocessen. En alternativ datormus baserad på MEMS-gyroskop har utvecklats. Utvecklingen är gjord utifrån de krav de tilltänka användarna ställde på den alternativa datormusen och enheten är utprovad och förbättrad i en iterativ process mellan utvecklare och användare, så kallad användarcentrerad utvecklingsprocess. MEMS-gyron var den typ av rörelsesensor som bäst svarade mot de krav som ställdes på enheten. De användare som deltog vid ett längre fältprov var samtliga nöjda och ville behålla musen. För att underlätta processen att välja rätt typ av gyro och att kunna utvärdera deras stabilitet under olika omgivningsfaktorer, såsom temperatur och vibrationer, har en testrig för gyron utvecklats. Människors rörelsemönster skiljer sig från industriella tillämpningar och därför behövs en speciell testrigg. Testriggen roterar gyron och mäter sensorsignalen under olika betingelser. Flera gyron kan testas samtidigt och testdatat kan sparas och analyseras i efterhand. Ett interaktivt datorbaserat träningsprogram har utvecklats och utvärderats vid en pilotstudie tillsammans med den alternativa datormusen. Syftet var att låta nackskadade utföra huvudrörelser och få en feedback på att de tränar rätt. Resultatet pekar på att detta kan vara en lovande metod. / Computers are important tools. People with motion disabilities sometimes are dependent on a computer and used as a technical aid the computer has improved the possibilities to perform meaningfull tasks, as writing, reading and communicating. However, disabled often need an alternative input device to control a computer.   The aim with this licentiate theses has been to develope techniques to support persons with motion limitations. Focus has been to develope alternative techniqes to control a computer. Important aspects have been user-friendlieness, possiblilities to perform individual adaptions and incorporatation of specifications from the intended users. Further, the input device has been evaluated by users and applied as a rehabilitation tool for a smaller patient group of persons with whiplash associated disorders.   Further, production aspects are important. To make the unit into a product, it has to be possible to produce and sell to a reasonable price. This has to be considered during the whole development process.   An alternative computer mouse based on a MEMS gyroscope has been developed. The specifications made by the users has been used as a starting point in the development and the unit has been evaluated and improved in an iterative process, so called user centric development. MEMS-gyros were the type of motion sensors most corresponding to the demands. The users that participated in a longer field test were all satisfied and wanted to keep the mouse.   To improve the process to choose right kind of gyro and to be able to evaluate their stability depending on factors as temperature and vibration, a test-rigg for gyros has been developed. Human motion pattern differs from industrial applications and therefor a special test-rigg was needed. The testrigg rotates the gyros and measures the sensor signal. Several gyros can be tested simultaneously and data can be stored and analysed afterwards.   An interactive computerbased training program has been developed and evaluated in a pilot study together with the altrenative computer mouse. The aim has been to let people with neck injuries perform head motions and get feedback that they perform the right kind of training. The result is promising.

The aim of this work has been to develop new knowledge about macromodelling of microsystems. Doing that, we have followed two different approaches for generating macromodels, namely model order reduction and lumped modelling. The latter is a rather mature method that has been widely recognized and used for a relatively long period of time. Model order reduction, on the other hand, is a relatively new area still in rapid development. Due to this, the parts considering reduced order modelling is strongly biased towards methodology and concepts, whereas parts on lumped modelling are biased towards systems and devices. In the first part of this thesis, we focus on model order reduction. We introduce some approaches for reducing model order for linear systems, and we give an example related to squeeze-film damping. We then move on to investigate model order reduction of nonlinear systems, where we present and use the concept of invariant manifolds. While the concept of invariant manifolds is general, we utilize it for reducing models. An obvious advantage of using invariant manifold theory is that it offers a conceptually clear understanding of effects and behaviour of nonlinear system. We exemplify and investigate the accuracy of one method for identifying invariant manifolds. The example is based on an industrialized dual-axis accelerometer. A new geometrical interpretation of external forcing, relating to invariant manifolds, is presented. We show how this can be utilized to deal with external forcing in a manner consistent with the invariance property of the manifold. The interpretation also aids in reducing errors for reduce models. We extend the asymptotic approach in a manner that makes it possible to create design-parameter sensitive models. We investigate an industrialized dual-axis accelerometer by means of the method and demonstrate capabilities of the method. We also discuss how manifolds for nonlinear dissipative systems can be found. Focusing on lumped modelling, we analyse a microresonator. We also discuss the two analogies that can be used to build electrical equivalents of mechanical systems. It is shown how the f → V analogy, linking velocity to voltage, is the natural choice. General properties of lumped modelling are investigated using models with varying degrees of freedom. Finally, we analyse an electromagnetic system, intended for levitating objects, and we demonstrate the scaling effects of the system. Furthermore, we prove the intrinsic stability of the system, although the floating disc will be slightly tilted. This is the first analysis done assessing the stability criterions of such a systems. The knowledge arising from the analysis gives strong indications on how such a system can be utilized, designed, and improved.

Microelectromechanical systems (MEMS) are miniaturized devices with high functionality. In recent years, MEMS products have become increasingly dominant in every aspect of the commercial market place. As the MEMS technology is in its infant stage and has several unique features compared to macro-scale products, it is faced with several challenges. One of them is that design and fabrication knowledge is very intrigue and thus very difficult to be accessible. An effective computer support to the MEMS product development is thus very important. This thesis study undertakes a thorough investigation into the MEMS product development process and its computer support. Specifically, the study examines the state-of-the-art in computer aided design systems in light of the support of product functionality. It is shown that MEMS product development involves high degree of uncertainty, which calls for an unconventional computer support. At this point, this study proposes an approach to construct a knowledge base in a fairly flexible and real-time manner. This approach is based on the extended function-behavior-structure framework and the template technique proposed in this thesis. The other finding is that the MEMS product development resembles the one-of-a-kind product (OKP) development. Therefore software tools for the OKP product development process can be applied to the MEMS product development process. These tools are examined, and further extensions upon them are proposed. Throughout the thesis, a microdispensing system is used as an example for illustration of concepts described in this thesis.

Following several terrorist attacks that have occurred during this decade, there is an urgent need to develop new technologies for the detection of highly energetic materials that can represent an explosive hazard. In an effort to contribute to the development of these new technologies, this work presents the design aspects of a chip-scale calorimeter that can be used to detect an explosive material by calorimetric methods. The aim of this work is to apply what has been done in the area of chip-scale calorimetry to the screening of highly energetic materials. The prototypes presented here were designed using computer assisted design and finite element analysis tools. The design parameters were set to satisfy the requirements of a sensor that can be integrated into a portable system (handheld) for field applications. The design approach consisted of developing a sensor with thick silicon membranes that can hold micro-size samples and that can operate at high temperatures, while keeping the cost of the sensor low. Contrary to other high resolution systems based on thin-film membranes, our prototypes exhibit a contribution from addenda that is comparable to that from the sample, and hence they have lower sensitivity. However, using thick membranes offers the advantage of producing sensors strong enough for this application and that have significantly lower cost. Once the prototypes were designed, the fabrication was performed using standard microfabrication techniques. Finally, the operation of our prototypes was demonstrated by conducting thermal analysis of different liquid and solid samples.

Microelectromechanical systems (MEMS) are miniaturized devices with high functionality. In recent years, MEMS products have become increasingly dominant in every aspect of the commercial market place. As the MEMS technology is in its infant stage and has several unique features compared to macro-scale products, it is faced with several challenges. One of them is that design and fabrication knowledge is very intrigue and thus very difficult to be accessible. An effective computer support to the MEMS product development is thus very important. This thesis study undertakes a thorough investigation into the MEMS product development process and its computer support. Specifically, the study examines the state-of-the-art in computer aided design systems in light of the support of product functionality. It is shown that MEMS product development involves high degree of uncertainty, which calls for an unconventional computer support. At this point, this study proposes an approach to construct a knowledge base in a fairly flexible and real-time manner. This approach is based on the extended function-behavior-structure framework and the template technique proposed in this thesis. The other finding is that the MEMS product development resembles the one-of-a-kind product (OKP) development. Therefore software tools for the OKP product development process can be applied to the MEMS product development process. These tools are examined, and further extensions upon them are proposed. Throughout the thesis, a microdispensing system is used as an example for illustration of concepts described in this thesis.