La microfluidique est un domaine très vaste qui étudie les comportements de fluides à l'échelle micrométrique. Grâce aux progrès de la microfabrication, elle suscite un nombre croissant d'applications en biologie ou chimie, et même très récemment en optique. En effet, son utilisation pour réaliser des cristaux photoniques est attractive par rapport aux technologies standards : elle permet une fabrication collective avec des interfaces très lisses. Dans cette perspective, cette thèse propose d'utiliser la microfluidique diphasique pour la fabrication de réseaux stables de microbulles, et pour intégrer de façon simple des fonctionnalités optiques réelles. Nous présentons d'abord la formation de réseaux hexagonaux de microbulles monodisperses de période dans la gamme 5-100 µm, contrôlée par la géométrie et les conditions d'écoulement. La qualité de ces cristaux a été révélée par imagerie de diffraction. Un photopolymère, utilisé comme liquide porteur, a permis l'obtention de structures stables sur plusieurs mois. Nous avons développé une technologie verre-verre qui permet la fabrication de canaux adaptés aux applications optiques : transparents, rigides et chimiquement résistants. Pour démontrer les potentialités de nos systèmes, nous avons réalisé des cristaux de bulles incluant des défauts contrôlés (lacune d'une bulle ou d'une ligne de bulles), éléments clés pour la conception de guides d'ondes ou de résonateurs. Nous utilisons des plots qui excluent les bulles de zones choisies, par compétition entre tension interfaciale et forces hydrodynamiques. Nous avons développé et validé expérimentalement un modèle qui prédit l'efficacité de cette méthode. La génération des microbulles sur puce est prometteuse pour la photonique : elle permet l'auto-organisation des structures avec une rugosité extrêmement faible. L'obtention de périodes comparables à la longueur d'onde est encore nécessaire pour la réalisation de fonctions basées sur les cristaux photoniques. Notre app roche doit permettre cette réduction de taille, car les limites de diffraction inhérentes à la photolithographie interviennent seulement pour la fabrication des canaux et non lors de la formation des bulles. Ce travail constitue donc une nouvelle approche, optofluidique, à la réalisation d'un guide d'onde, un filtre ou un résonateur optique.

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Exploiting wireless communications has had an unstoppable growth in the last years. In this attracting scenario, the Ultra Wide Band (UWB) market represents one of the main interesting targets for semiconductor industry. The availability of newer and larger bandwidth in the frequency spectrum (60 GHz and 77 GHz) opens to the possibility of higher bitrates communications. The technology cost reduction is made possible by the use of silicon as semiconductor substrate in the place of classical heterojunction materials. The rapid reduction of the technological node (seen as the thinning of the gate channel) in the new generation of CMOS transistors allows obtaining faster transistors that become usable on V band applications. Therefore, the digital origin of the technology yields two additional advantages. First of all, the facilities for the circuits' production already exist as well as the recipe to create the devices on the substrate. The only additive cost remains the characterization of the technology at mm-wave frequencies. The second fundamental advantage is the possibility to have a complete integration of the system in the same dies with a substantial reduction of packaging and interconnection costs. The objectives of this thesis is the design and the modeling of a complete 60 GHz UWB transceiver starting from the characterization and the optimization of the single subcomponents. The main feature that constitutes the principal constraint of the entire work of this thesis is the high efficiency required for the transceiver front - end. The energy safe capability, in fact, represents the strength point of this project, being the system conceived for wireless sensors network applications. Passive components as inductors and RF lines, have been the first elements that have been designed and characterized. Then the structure of CMOS transistor have been analyzed and characterized in order to obtain performances as higher as possible, in particular for wide transistors. The knowledge acquired during this first part has allowed the developed of high quality factor inductors and high performance transistors (used in the design of upconversion mixer). In addition, the optimum correspondence between simulations and measurements combined with the gained experience on the RF electromagnetic simulations have been exploited to create a series of innovative (when possible) passive structures as baluns, power splitters and power couplers. The second significant part of this work has been consecrated to the modeling of a series of high performance active circuits in the transmitter and the receiver blocks (upconversion mixer, voltage controlled oscillator ad a series of differential and single-ended buffers). The behavior of these structures has been accurately investigated and optimized in order to be later efficiently integrated in the complete transceiver system. The systems are finally integrated in two different dies, transmitter and receiver blocks, and the 60 GHz link has been yield by a demostrator set-up.

Les réseaux de capteurs sans fil (WSN) ont attiré un grand intérêt dans la dernière décennie, et ont apporté des solutions dans un nombre croissant d'applications. Toutefois, certaines d'entre elles restent irréalisables en raison de forts points de blocage non résolus, comme un manque de synchronisation entre les prises de mesures, ainsi que des débits de données trop faibles. Ce travail apporte une solution à ces deux points majeurs via la conception d'un noeud communicant sans fil spécifique. Celle ci, basée sur la conception croisée, utilise les propriétés temporelles des modulations UltraLarge Bande (UWB) pour permettre une synchronisation très précise ainsi qu'un débit de données élevé. Notre démonstrateur ASIC basé sur ces travaux permet une précision de synchronisation de 2 ns pour une modulation IR-UWB sur une bande passante de 1,5 GHz. Cette thèse décrit le protocole de synchronisation WiDeCS et la conception de deux preuves de concept fonctionnelles sur FPGA et ASIC.

Les matériaux composites à base de fibre carbone suscitent un intérêt grandissant dans l'industrie en général et avionique en particulier. Très appréciés pour leur résistance exceptionnelle aux efforts de traction ils présentent également un poids bien plus faible que les métaux y compris l'aluminium. Cela permet d'envisager la construction d'aéronefs d'une très grande solidité tout en réduisant significativement leur consommation en carburant. Cependant les composites carbone sont relativement fragiles sous des efforts en flexion ou compression. Leur durée de vie est peu connue et dépend fortement de la géométrie des pièces qui sont souvent surdimensionnées par sécurité. Afin de prévenir d'éventuels accidents et conserver des pièces légères il est indispensable d'évaluer leur état de santé. L'objectif de cette thèse est la conception d'une solution d'instrumentation à base de capteurs miniaturisés en technologie silicium sensibles aux vibrations mécaniques et capables de détecter l'apparition d'un défaut dans la structure. Nous développé un procédé de fabrication simple et robuste pour des capteurs dont l'élément sensible est une jonction PN de type Zéner implémentée dans du polysilicium. Nous avons démontré dans un premier temps une sensibilité aux vibrations mécaniques. La capacité de ces capteurs à faire du suivi de réticulation en autoclave a également été démontrée. La phase suivante a concerné l'étude d'un procédé de packaging souple robuste et modulable pour la mise en réseau des capteurs. Enfin la dernière étape concerne l'étude d'un circuit électronique permettant la lecture du signal et la réduction du bruit de fond.

Ces travaux de recherche visent à associer la technologie des polymères à empreintes moléculaires à des dispositifs acoustiques à onde de Love afin de réaliser un biocapteur. L'objectif majeur était la mise au point d'un protocole de dépôt localisé de polymères non imprimés (NIP) et imprimés (MIP) en films minces compatibles avec la propagation de l'onde élastique. Une seconde partie des travaux a porté sur une caractérisation des films et des capteurs ainsi réalisés, par microscopie à balayage et mesures de détection sous gaz. Des éléments relatifs aux propriétés mécaniques (porosité, surface spécifique) des NIPs, des MIPs avant extraction de la molécule cible, puis après extraction et après recapture, ont permis de valider le principe du capteur, ouvrant la voie à l'application en milieu liquide dans le cadre de travaux débutés parallèlement.

Polymers play an integral part in the semiconductor electronic industry. Due to the expanding diversity of a polymer s structural design and the resulting properties, different polymers serve as different components in the makeup and fabrication of the electronic package. The limiting factor in computer processing speed shifts from the transistors gate delay to the interconnect delay below a circuit line width of 1.8 μm for interlayer dielectrics. Silicon dioxide has been used as the insulating layer between metal lines for many computer chip generations. Low dielectric constant polymers will need to supplant silicon dioxide as interlayer dielectrics in order to develop reliable circuits for future generations. Along with serving as interlayer dielectrics, low dielectric constant polymers are also incorporated in first and second level electronic packaging. Deposition and patterning of these polymers can be significantly reduced by using photodefinable polymers. Most photodefinable polymers are in a precursor form for exposure and development in order to dissolve in industrial developers. Once developed, the polymer precursors are cured to produce the final polymer structure. This temperature is as high as 350 oC for many polymers. Thermal curing sets limitations on the use of the polymer in the electronics industry because of either the unwanted stress produced or the incompatibility of other electronic components that do not survive the thermal cure. In addition to a low dielectric constant and photodefinability, many other properties are needed for successful implementation. Polymers must be soluble in organic solvents in order to spin coat films. Water absorption increases the dielectric constant of the patterned films and can lead to various adhesion problems and cause delamination of the film. Mismatches between the coefficients of thermal expansion in adjacent layers can produce residual film stresses which leads to warping of the substrate or interfacial delamination. The glass transition temperature must be high because the thermal expansion is greatly increased when the glass transition temperature is exceeded. A high Young s modulus is also required to withstand external forces from thermal, electrical, and packaging stresses. The goal of this research was to develop novel, low dielectric, photodefinable polymers that can be processed at low temperatures. All polymers discussed will contain one of two monomers with hexafluoroalcohol (HFA) functional groups. Fluorine provides many properties that are advantageous for low dielectric applications whereas alcohols absorb water and increase the dielectric constant. Characterization of the polymers show the effect the fluorine has on the alcohol s high water absorption. All polymers will be synthesized by condensation polymerization of a diamine with a dianhydride or diacid chloride. All other polymers will contain a novel HFA diamine. A new thermoplastic polymer structure based on the cyclization of an HFA situated ortho to an amide linkage produces a benzoxazine ring in the polymer backbone. Cyclization to form polybenzoxazines occurs at temperatures considerably lower than that needed to form polyimides. The lowest processing temperatures are achieved with protection of the HFA that can be cleaved with a photoacid generator.

Progress in the microelectronics industry is driven by smaller and faster transistors. As feature sizes in integrated circuits become smaller and liquid chemical waste becomes an even greater environmental concern, gas expanded liquids (GXLs) may provide a possible solution to future device fabrication limitations relative to the use of liquids. The properties of GXLs such as surface tension can be tuned by the inclusion of high pressure gases; thereby, the reduced surface tension will allow penetration of cleaning solutions into small features on the nanometer scale. In addition, the inclusion of the gas decreases the amount of liquid necessary for the photoresist and etch residue removal processes. This thesis explores the role of CO2-based GXLs for photoresist and etch residue removal. The gas used for expansion is CO2 while the liquid used is methanol. The cosolvent serving as the removal agent is tetramethyl ammonium hydroxide (TMAH) which upon reacting with CO2 becomes predominantly tetramethyl ammonium bicarbonate (TMAB).

As the science and technology advance, people are looking for new discoveries to solve the existing problems and improve the quality of life. In this processes of development, nanoscience and nanotechnology have attracted technologists' attention and turned out to be one of the most promising technologies that could have a revolutionary impact. Znic Oxide (ZnO) nanostructures, in particular nanowires (NWs), have the potential to be one of such revolutionary material. ZnO is a piezoelectric, transparent and semiconducting material. With a direct band gap of 3.37eV and large excitation binding energy (60meV), ZnO exhibits near-UV emission, and transparent conductivity. ZnO NWs, with all of the properties of bulk ZnO, have other properties that are distinct to nanoscale material. All of these make ZnO NWs a very unique material that has many potential applications in system miniaturization. System-on-package (SOP) technology is a new concept developed to solve the integration problem in microelectronic industry. SOP technology paradigm provides system-level miniaturization in a package size that makes today's hand-held devices into multi-functional systems, with applications ranging from computing, wireless communications, health care to personal security. The SOP is a system miniaturization technology that ultimately integrates nanoscale thin film components for batteries, thermal structures, active and passive components in low cost organic packaging substrates, leading to micro to nanoscale modules and systems. The goal of this research is to investigate and utilize the unique properties of ZnO NWs and apply them to the fabrication of devices that can be integrated with SOP platform. The issues include developing techniques to manipulate and align ZnO NWs; developing contact preparation method to improve the contact conductance for the fabrication of ZnO NW based devices. Also, the investigation of the oxygen diffusion coefficient in ZnO NWs is carried out, which serves as the basis of ZnO NWs for sensing applications. Two practical applications, which include fabricating and characterizing SOP compatible ZnO NW based bio-sensor and SOP compatible ZnO NW based nano-generator, are evaluated. Finally the remaining work beyond the scope of the thesis is outlined.

The objectives of this thesis are to develop and validate laser ultrasonic inspection methods for on-line testing of microelectronic devices. Electronic packaging technologies such as flip chips and BGAs utilize solder bumps as electrical and mechanical connections. Since they are located hidden from view between the device and the substrate, defects such as cracks, voids, misalignments, and missing bumps are difficult to detect using non-destructive methods. Laser ultrasonic inspection is capable of detecting such defects by utilizing a high power laser pulse to induce vibrations in a microelectronic device while measuring the out of plane displacement using an interferometer. Quality can then be assessed by comparing the vibration response of a known-good device to the response of the sample under inspection. The main limitation with the implementation of laser ultrasonic inspection in manufacturing applications is the requirement to establish a known-good reference device utilizing other non-destructive methods. My work will focus on developing a method to inspect flip chip devices without requiring a previously established reference. The method will automatically examine measurement data from a large sample set to identify those devices which are most similar. The selected devices can then be utilized to compose a hybrid reference signal which can be used for comparison and defect detection. Current trends in the electronic packaging industry continue to drive toward increased solder bump density, making it increasingly difficult to generate strong ultrasonic signals in these stiffer devices. To overcome this difficulty, I propose a new excitation method which places the source of ultrasound at the inspection location for each test point on the device surface. This ensures that the same power is available for each inspection location while also increasing the signal to noise ratio. The hardware implementation of this method reduces the system complexity and required automation, which can significantly reduce equipment cost and inspection time. The implementation of the proposed excitation method in conjunction with the use of a hybrid reference signal for defect detection will improve the utility of the laser ultrasonic inspection technique to on-line inspection applications where no other non-destructive methods are currently available.