The conventional techniques of manufacturing large-size structures in a very large plate pose severe challenges in making microstructures. In contrast, semiconductor process that employs lithographic processes to form micro scale features is limited in its wafer size. In ordre to modify the defeat of shadow mask. This thesis propose to use TMAH anisotropic wet etching process and 2D- joining technique to fabricate silicon shadow mask. The potential of this technique would be significant for a very large plate beyond a wafer size with microstructures, and provides a new approach with a high replication and potentially low cost. In the numerical analysis, this study uses the finite element software, ANSYS, to simulate shadow mask with different size, material, and temperature displacement situation. The results shows the feasibility of silicon shadow mask used in the thermal evaporation process. It indicates that this design could have smoother pattern and reduce the limitation of Organic Light-Emitting Diode resolution.

Novel micro patterning techniques have been developed for the patterning of volatile functional materials which cannot be conducted by conventional photolithography. First, in order to create micro patterns of volatile materials (such as bio-molecules and organic materials), micro-contact printing and shadow mask methods are investigated. A novel micro-contact printing technique was developed to generate micro patterns of volatile materials with variable size and density. A PDMS (Polydimethylsiloxane) stamp with 2-dimensional pyramidal tip arrays has been fabricated by anisotropic silicon etching and PDMS molding. The variable size of patterns was achieved by different external pressures on the PDMS stamp. A novel inking process was developed to enhance the uniformity and repeatability in micro-contact printing. The variable density of patterns could be obtained by alignment using x-y transitional stage and multiple stamping with a z-directional moving part. Second, for direct patterning of small molecule organic materials (e.g. pentacene), a novel shadow mask method has been developed with a simple and accurate alignment system. To make accurate dimensions of patterning windows, a silicon wafer was used for the shadow mask since a conventional semiconductor process gives a great advantage for accurate and repeatable fabrication processes. A sphere ball alignment system was developed for the accurate alignment between the shadow mask and the silicon substrate. In this alignment system, four matching pyramidal cavities were fabricated on each side of the shadow mask and silicon wafer substrate using an anisotropic silicon bulk etching. By placing four steel spheres in between the matching cavities, the self-alignment system could be demonstrated with 2-3um alignment accuracy in x-y directions. For OTFT (Organic thin film transistor) application, an organic semiconducting layer was directly deposited and patterned on the substrate using the developed shadow mask method. On the other hand, novel embedding techniques were developed for enabling conventional semiconductor processes including photolithography to be applied on the small substrate. The polymer embedding method was developed to provide an extended processing area as well as easy handling of the small substrate. As an application, post CMOS (Complementary metal-oxide-semiconductor) integration of a relatively large microstructure which might be even larger than the substrate was demonstrated on a VCO (Voltage-controlled oscillator) chip. In addition, micro patterning on the optical fiber was demonstrated by using a silicon wafer holder designed to surround and hold the optical fiber. The micro Fresnel lens could be successfully patterned and integrated on the optical fiber end.

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A self-aligning nanostencil mask is used to fabricate circular features of tin, indium and silver on an atomically clean Si(001) substrate. The shadow mask limits deposited material to areas under openings in the mask, leaving adjacent clean areas for material to diffuse. STM, SEM and AFM have been used to study the surface diffusion of these metals in UHV. The diffusion of tin is relatively limited in comparison to the other metals. Indium forms metal islands that dissolve over time and contribute to the spreading of a surrounding single layer film. Lastly, silver forms a film that spreads even in the absence of metal islands.

A self-aligning nanostencil mask is used to fabricate circular features of tin, indium and silver on an atomically clean Si(001) substrate. The shadow mask limits deposited material to areas under openings in the mask, leaving adjacent clean areas for material to diffuse. STM, SEM and AFM have been used to study the surface diffusion of these metals in UHV. The diffusion of tin is relatively limited in comparison to the other metals. Indium forms metal islands that dissolve over time and contribute to the spreading of a surrounding single layer film. Lastly, silver forms a film that spreads even in the absence of metal islands.

Micro-Electro-Mechanical Systems (MEMS) micromirrors have been developed for more than two decades along with the development of MEMS technology. They have been used into many application fields: optical switches, digital light projector (DLP), adoptive optics (AO), high definition (HD) display, barcode reader, endoscopic optical coherence tomography (OCT) and confocal microscope, and so on. Especially, MEMS mirrors applied into endoscopic OCT and confocal microscope are the intensive research field. Various actuation mechanisms, such as electrostatic, electromagnetic, electro bimorph thermal, electrowetting, piezoelectric (PZT) and hybrid actuators, are adopted by different types of micromirrors. Among these actuators, the electrostatic is easily understood and simple to realize, therefore, it is broadly adopted by a large number of micromirrors. This thesis reports the design, fabrication, and characterization of a 2-D Silicon-on-insulation (SOI) MEMS micromirror with sidewall (SW) electrodes for endoscopic OCT or confocal microscope imaging. The biaxial MEMS mirror with SW electrodes is actuated by electrostatic actuators. The dimension of mirror plate is 1000micron×1000micron, with a thickness of a 35micron. The analytical modeling of SW electrodes, fabrication process, and performance characteristics are described. In comparison to traditional electrostatic actuators, parallel-plate and comb-drive, SW electrodes combined with bottom electrodes achieve a large tilt angle under a low drive voltage that the comb-drive does and possess fairly simple fabrication process same as that of the parallel-plate. A new fabrication process based on SOI wafer, hybrid bulk/surface micromachined technology, and a high-aspect-ratio shadow mask is presented. Moreover, the fabrication process is successfully extended to fabricate 2×2 and 4×4 micromirror arrays. Finally, a biaxial MEMS mirror with SW electrodes was used into Confocal MACROscope for imaging. Studied optical requirements in terms of two optical configurations and frequency optimization of the micromirror, the biaxial MEMS mirror replaces the galvo-scanner and improves the MACROscope. Meanwhile, a new Micromirror-based Laser Scanning Microscope system is presented and allows 2D images to be acquired and displayed.

Micro-Electro-Mechanical Systems (MEMS) micromirrors have been developed for more than two decades along with the development of MEMS technology. They have been used into many application fields: optical switches, digital light projector (DLP), adoptive optics (AO), high definition (HD) display, barcode reader, endoscopic optical coherence tomography (OCT) and confocal microscope, and so on. Especially, MEMS mirrors applied into endoscopic OCT and confocal microscope are the intensive research field. Various actuation mechanisms, such as electrostatic, electromagnetic, electro bimorph thermal, electrowetting, piezoelectric (PZT) and hybrid actuators, are adopted by different types of micromirrors. Among these actuators, the electrostatic is easily understood and simple to realize, therefore, it is broadly adopted by a large number of micromirrors. This thesis reports the design, fabrication, and characterization of a 2-D Silicon-on-insulation (SOI) MEMS micromirror with sidewall (SW) electrodes for endoscopic OCT or confocal microscope imaging. The biaxial MEMS mirror with SW electrodes is actuated by electrostatic actuators. The dimension of mirror plate is 1000micron×1000micron, with a thickness of a 35micron. The analytical modeling of SW electrodes, fabrication process, and performance characteristics are described. In comparison to traditional electrostatic actuators, parallel-plate and comb-drive, SW electrodes combined with bottom electrodes achieve a large tilt angle under a low drive voltage that the comb-drive does and possess fairly simple fabrication process same as that of the parallel-plate. A new fabrication process based on SOI wafer, hybrid bulk/surface micromachined technology, and a high-aspect-ratio shadow mask is presented. Moreover, the fabrication process is successfully extended to fabricate 2×2 and 4×4 micromirror arrays. Finally, a biaxial MEMS mirror with SW electrodes was used into Confocal MACROscope for imaging. Studied optical requirements in terms of two optical configurations and frequency optimization of the micromirror, the biaxial MEMS mirror replaces the galvo-scanner and improves the MACROscope. Meanwhile, a new Micromirror-based Laser Scanning Microscope system is presented and allows 2D images to be acquired and displayed.

Fabrication of ordered anodic alumina nanopore arrays and anodization parameters including electrolyte, concentration, voltage, temperature and time have been investigated. Cobalt nanoparticles were electrodeposited at the bottom of the pores. Vertically aligned, open-tipped multi-walled carbon nanotube arrays of high density and uniformity were synthesized via a flame method on silicon substrates using a nanoporous template of anodized aluminum oxide. The diameter and length of the nanotubes are controlled by the geometry of the aluminum oxide template. It is the cobalt catalyst particles, not the porous aluminum templates, help the growth of carbon nanotubes through graphitization and bonding of carbon nanotubes to the silicon substrates. Fabrication of nano-structures has been demonstrated. Nano-trenches of 20 nm have been achieved using single-walled nanotube bundles as shadow masks, which were aligned across electrodes under high frequency AC voltage.

L’imagerie multispectrale permet d’améliorer la détection et la reconnaissance de cibles dans les applications de surveillance. Elle consiste à analyser des images de la même scène acquises simultanément dans plusieurs bandes spectrales grâce à un filtrage. Cette thèse étudie la possibilité de réaliser une matrice de 4 filtres Fabry Pérot (FP) intégrés 3D et ajustables par actionnement électrostatique dans le domaine visible-proche infrarouge. Les miroirs fixes des filtres FP sont des multicouches ZnS/YF₃ déposés sur un wafer de borosilicate, et les miroirs mobiles sont des membranes multicouches PECVD SiNH/SiOH encastrées sur une structure mobile très compacte micro-usinée dans un wafer en silicium. Les performances optiques des filtres FP ont été optimisées en prenant en compte la dissymétrie et le déphasage à la réflexion des miroirs. La structure mobile a été modélisée par éléments finis pour minimiser ses déformations lors de l’actionnement. Les étapes critiques des procédés de fabrication des miroirs mobiles en technologie Si ou SOI ont été mises au point : i) la fabrication et la libération par gravures profondes DRIE et XeF₂ des membranes multicouches avec une contrainte résiduelle ajustée par recuit et une réflectance voisine de 50% dans une large gamme spectrale, ii) le contrôle des vitesse de la gravure DRIE avec des motifs temporaires permettant la gravure simultanée de motifs de largeur et de profondeur variables, et iii) la délimitation de motifs sur surfaces fortement structurées à l’aide de pochoirs alignés mécaniquement ou de films secs photosensibles. Ces travaux ouvrent la voie vers une réalisation complète d’une matrice de filtres FP intégrés 3D. / Multispectral imaging is used to improve target detection and identification in monitoring applications. It consists in analyzing images of the same scene simultaneously recorded in several spectral bands owing to a filtering. This thesis investigates the possibility to realize, an array of four 3D integrated Fabry-Perot (FP) filters that are tunable in the visible-near infrared range by electrostatic actuation. The fixed mirrors of the FP filters are ZnS/YF₃ multilayers deposited on a borosilicate wafer, and the movable mirrors are PECVD SiNH/SiOH multilayer membranes clamped in a very compact movable structure micromachined in a Si wafer. A 3rd glass wafer is used for filters packaging. Optical performances of the FP filters have been optimized by taking into account the asymmetry and the reflection phase shift of the mirrors and the mobile structure has been modeled by finite elements analysis notably to minimize its deformation during actuation. The critical steps of the movable mirrors fabrication process in Si or SOI technology have been developed : i) the fabrication and the release by DRIE and XeF₂ etching of 8 or 12 layers membranes with a residual stress tunable by annealing and a reflectance close to 50% in broad wavelength range (570-900nm), ii) the control with temporary patterns of the simultaneous deep etching of patterns with different widths and depths, and iv) various patterning techniques on highly structured surfaces based on shadow masks (with mechanical alignment) or laminated photosensitive dry films. These results open the way towards the full realization of an array of 3D integrated FP filters.

The work presented in this thesis investigates transitions between quantum states in superconducting double dots (SDDs), a nanoscale device consisting of two aluminium superconducting islands coupled together by a Josephson junction, with each dot connected to a normal state lead. The energy landscape consists of a two level manifold of even charge parity Cooper pair states, and continuous bands corresponding to charge states with single quasiparticles in one or both islands. These devices are fabricated using shadow mask evaporation, and are measured at sub Kelvin temperatures using a dilution refrigerator. We use radio frequency reflectometry to measure quantum capacitance, which is dependent on the quantum state of the device. We measure the quantum capacitance as a function of gate voltage, and observe capacitance maxima corresponding to the Josephson coupling between even parity states. We also perform charge sensing and detect odd parity states. These measurements support the theoretical model of the energy landscape of the SDD. By measuring the quantum capacitance in the time domain, we observe random switching of capacitance between two levels. We determine this to be the stochastic breaking and recombination of single Cooper pairs. By carrying out spectroscopy of the bath responsible for the pair breaking we attribute it to black-body radiation in the cryogenic environment. We also drive the breaking process with a continuous microwave signal, and find that the rate is linearly proportional to incident power. This suggests that a single photon process is responsible, and demonstrates the potential of the SDD as a single photon microwave detector. We investigate this mechanism further, and design an experiment in which the breaking rate is enhanced when the SDD is in the antisymmetric state rather than the symmetric state. We also measure the quantum capacitance of a charge isolated double dot. We observe 2e periodicity, indicating the tunnelling of Cooper pairs and the lack of occupation of quasiparticle states. This work is relevant to the range of experiments investigating the effect of non-equilibrium quasiparticles on the operation of superconducting qubits and other superconducting devices.