This research delineates the design of a nanolithographic process for nanometer scale surface patterning. The process involves the combination of serial atomic force microscope (AFM) based nanolithography with the parallel patterning capabilities of soft lithography. The union of these two techniques provides for a unique approach to nanoscale patterning that establishes a research knowledge base and tools for future research and prototyping.To successfully design this process a number of separate research investigations were undertaken. A custom 3-axis AFM with feedback control on three positioning axes of nanometer precision was designed in order to execute nanolithographic research. This AFM system integrates a computer aided design/computer aided manufacturing (CAD/CAM) environment to allow for the direct synthesis of nanostructures and patterns using a virtual design interface. This AFM instrument was leveraged primarily to study anodization nanolithography (ANL), a nanoscale patterning technique used to generate local surface oxide layers on metals and semiconductors. Defining research focused on the automated generation of complex oxide nanoscale patterns as directed by CAD/CAM design as well as the implementation of tip-sample current feedback control during ANL to increase oxide uniformity. Concurrently, research was conducted concerning soft lithography, primarily in microcontact printing (µCP), and pertinent experimental and analytic techniques and procedures were investigated.Due to the masking abilities of the resulting oxide patterns from ANL, the results of AFM based patterning experiments are coupled with micromachining techniques to create higher aspect ratio structures at the nanoscale. These relief structures are used as master pattern molds for polymeric stamp formation to reproduce the original in a parallel fashion using µCP stamp formation and patterning. This new method of master fabrication provides for a useful alternative to conventional techniques for soft lithographic stamp formation and patterning. / Dissertation

<p>During the past two decades, soft lithographic techniques that circumvent the limitations of photolithography have emerged as important tools for the transfer of patterns with sub-micron dimensions. Among these techniques, microcontact printing (uCP) has shown special promise. In uCP, an elastomeric stamp is first inked with surface-reactive molecules and placed in contact with an ink-reactive surface, resulting in pattern transfer in the form of self-assembled monolayers in regions of conformal contact. The resolution in uCP is ultimately limited to the diffusion of ink and the elastomechanical properties of the bulk stamping material. </p> <p>One way to improve resolution is to eliminate diffusion by using inkless methods for pattern transfer. Inkless catalytic-uCP uses a chemical reaction between a stamp-immobilized catalyst and surface bearing cognate substrate to transfer pattern in the areas of conformal contact. By using pre-assembled cognate surfaces, the approach extends the range of surfaces readily amenable to patterning while obviating diffusive resolution limits imposed by traditional uCP. </p> <p>In this thesis, we report two methods using inkless catalytic uCP: biocatalytic-uCP utilizes an immobilized enzyme as a catalyst whereas catalytic-uCP utilizes an immobilized small molecule as a catalyst, such as an acid or base. Both catalytic techniques demonstrate pattern transfer at the microscale while using unconventional, acrylate-based stamp materials. Previous results produced with catalytic-uCP have shown pattern transfer with sub-50 nm edge resolution. In this demonstration of catalytic-uCP, we use the technique to demonstrate a bi-layered patterning technique for H-terminated silicon, the foremost material in semi-conductor fabrication. This technique simultaneously protects the underlying silicon surface from degradation while a highly-reactive organic overlayer remains patternable by acidic-functionalized PU stamps. Lines bearing widths as small as 150 nm were reproduced on the reactive SAM overlayer, which would not be possible without circumvention of diffusion. Before and after patterning, no oxidation of the underlying silicon was observed, preserving desired electronic properties throughout the whole process. This bi-patterning technique could be extended to other technologically-relevant surfaces for further application in organic-based electronic devices and other related technologies.</p> / Dissertation

ZnO nanostructures have been investigated for quite a long time. However, only recently they triggered much interest due to advances in materials synthesis and characterization, as well as emerging demand for new nanostructured materials in novel device implementations. A large part of the work was devoted to exploring new methodology for patterning growth sites and controlling nanowires morphology using the deposition methods that are compatible with integrated circuits (IC) processing. Microcontact printing was used to pattern the seeding layer, and, subsequently, ZnO nanowires through a resistless soft lithography process. When considering hydrothermal growth of ZnO nanowires in the framework of IC compatible techniques, it is favorable to keep the chemistry of the process constant, while tailoring morphological properties of ZnO nanowires through other means. Therefore, control over morphology of ZnO nanowires was realized by setting the physical properties of seeding layers. Atomic Layer Deposition (ALD) was used to deposit seeding layer required for hydrothermal growth and the effect of the physical properties of ALD thin films on resultant ZnO nanowires was studied. Opto-electrochemical properties of ZnO nanowires were studied in various electrolytes and performance of ZnO nanowires as an electrode material for multifunctional applications was investigated. Also, bulk nucleation and growth of novel aster-like nanostructures was investigated. These nanostructures may prove useful for creation of mechanically reinforced biocompatible polymers. Another key objective of the present work was to create strategies for controlled growth of ZnO nanowires on substrates previously unavailable for conventional hydrothermal growth of ZnO nanowires. The newly developed approach greatly facilitates growth of ZnO nanowires in confined microstructures, which greatly enhances the possibilities for the usage of ZnO nanowires in applications where they act as a porous electrode. These novel techniques open wide possibilities for improving performance of devices such as dye sensitized solar cells or supercapacitors.

The advent of numerous tools, ease of techniques, and concepts related to nanotechnology, in combination with functionalization via simple chemistry has made gold important for various biomedical applications. In this dissertation, the development and characterization of planar gold surfaces with responsive hydrogel patterns for rapid point of care sensing and the functionalization of gold nanoparticles for drug delivery are highlighted. Biomedical micro- and nanoscale devices that are spatially functionalized with intelligent hydrogels are typically fabricated using conventional UV-lithography. Herein, precise 3-D hydrogel patterns made up of temperature responsive crosslinked poly(N-isopropylacrylamide) over gold were synthesized. The XY control of the hydrogel was achieved using microcontact printing, while thickness control was achieved using atom transfer radical polymerization (ATRP). Atomic force microscopy analysis showed that to the ATRP reaction time governed the pattern growth. The temperature dependent swelling ratio was tailored by tuning the mesh size of the hydrogel. While nanopatterns exhibited a broad lower critical solution temperature (LCST) transition, surface roughness showed a sharp LCST transition. Quartz crystal microbalance with dissipation showed rapid response behavior of the thin films, which makes them applicable as functional components in biomedical devices. The easy synthesis, relative biocompatibility, inertness, and easy functionalization of gold nanoparticles (GNPs) have made them useful for various biomedical applications. Although ATRP can be successfully carried out over GNPs, the yield of stable solution based GNPs for biomedical applications prove to be low. As an alternative approach, a novel method of ISOlating, FUnctionalizing, and REleasing nanoparticles (ISOFURE) was proposed. Biodegradable poly(β-amino ester) hydrogels were used to synthesize ISOFURE-GNP composites. ATRP was performed inside the composite, and the final hydrogel coated GNPs were released via matrix degradation. Response analysis confirmed that the ISOFURE method led to the increased stability and yield of the hydrogel coated ISOFURE-GNPs. The ISOFURE protocol was also utilized in functionalizing GNPs with enzyme catalase in the absence of a stabilizing reagent. Biotin-streptavidin affinity was used as the bioconjugation method. Activity analysis of the conjugated enzyme showed that the ISOFURE-GNPs showed enhanced biomolecular loading relative to solution based stabilizing reagent passivated GNPs.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22776号 / 工博第4775号 / 新制||工||1747(附属図書館) / 京都大学大学院工学研究科材料工学専攻 / (主査)教授 杉村 博之, 教授 邑瀬 邦明, 教授 宇田 哲也 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

Trilayer polypyrrole microactuators that can operate in air have previously been developed. They consist of two outer layers ofthe electroactive polymer polypyrrole (PPy) and one inner layer of a porous poly(vinylidene flouride) (PVDF) membranecontaining a liquid electrolyte. The two outer layers of PPy are each connected with gold electrodes and separated by the porousPVDF membrane. This microtool is fabricated by bottom-up microfabrication However, porous PVDF layer is not compatible with bottom upmicrofabrication and highly swollen SPE suffers from gold electrode delamination. Hence, in this MSc project/thesis a novelmethod of flexible electrode fabrication with conducting polymers was developed by soft lithography and drop-on-demandprinting. The gold electrodes were replaced by patterned vapor phase polymerized (VPP) poly(3,4-ethylenedioxythiophene) (PEDOT)electrodes due to its high electrical conductivity and versatile process ability. The replacement of the stiff gold electrodes byflexible and stretchable PEDOT allowed high volume change of the material and motions. The PEDOT electrodes werefabricated by patterning the oxidant iron tosylate using microcontact printing and drop-on-demand printing. Moreover, thePVDF membrane has been replaced by a nitrile butadiene rubber/poly(ethylene oxide) semi-interpenetrating polymer network(IPN) to increase ion conductivity and strechability and hence actuator performance.

L'enjeu de ce travail est la réalisation de circuits électroniques sur des pièces polymères injectées à forme 3D, appelées MIDs, par microtamponnage (μTP). Le μTP, est une technique de localisation de substances (chimiques ou biologiques) par contact mécanique d'un tampon structuré sur un substrat. Il permet de localiser les pistes conductrices des MIDs en utilisant deux protocoles : le μTP passif et le μTP actif. La première méthode consiste à déposer de manière localisée un thiol par μTP sur la surface de la pièce préalablement métallisée. Le thiol permet de protéger les pistes métalliques qui doivent être conservées après gravure humide. Dans la seconde, un catalyseur (du palladium) est déposé par μTP, suivi de la métallisation electroless des pistes. La problématique du μTP 3D a été étudiée à l'aide d'un tampon épousant la forme de la pièce. Nos résultats expérimentaux couplés à des simulations par éléments finis de la déformation du tampon lors de sa compression au moment du contact avec la pièce, nous ont permis de déterminer les paramètres clefs du procédé : l'alignement du tampon par rapport à la pièce, la gestion du contact et la fabrication du tampon. Il a été mis en évidence que la tolérance de l'alignement est de l'ordre de 100μm pour des motifs structurés de 250μm de hauteur. Un tampon composé d'un support rigide surmonté d'une couche mince structurée permet de limiter ses déformations lors de sa compression. Les enseignements tirés nous ont permis de réaliser nos premiers circuits par μTP à l'aide d'une machine originale développée au laboratoire. La problématique de l'épaississement des couches de cuivre adhérentes sur des pièces en LCP est également abordée, un protocole d'épaississement ayant été validé / The main challenge of this work was the production of electronic circuits on injected 3Dshaped polymer components, called MIDs, by microcontact printing (μCP). μCP is a substance (chemical or biological) localisation technique through mechanical contact between a patterned stamp and a substrate. It enables the MIDs’ conductor tracks to be located using two techniques: passive μCP and active μCP. The first method involves locally depositing a thiol by μCP on the substrate’s surface, which has previously been coated with a thin metallic film. The thiol protects the metallic tracks, which must be preserved after wet chemical etching. Regarding the second method, a catalyst (palladium) is deposited by μCP, followed by the electroless metallization of the tracks. The 3D μCP issue was studied using a stamp, which matched the shape of the substrate. Our experimental results combined with finite element simulations of stamp deformation during compression and whilst in contact with the substrate, revealed the key parameters of the process: stamp/substrate alignment, contact control and stamp manufacturing. We found that the alignment tolerance was around 100μm for a 250μm thickness structured design. A stamp with a rigid support covered in a structured thin film minimises deformation during compression. Thanks to the lessons learned, we carried out our first circuits using μCP with a new machine, which was developed in the laboratory. We also addressed the problem of thickening adhesive copper layers on LCP components, as a thickening procedure had already been validated

We reported a non-crosslinking approach to synthesize nitroxide radical polymer brushes for thin-film electrodes via surface-initiated atom transfer radical polymeization (SI-ATRP), which was effective to yield the organic radical polymer brushes with high grafting density and to attain a uniform surface. As mentioned above, the covalent bonding of nitroxide polymer brushes to the conducting substrate not only prevented the polymer dissolution into organic electrolyte solution but improved the cycle life performance of batteries. Moreover, they can be the potential application in microbatteries by using microcontact printing to produce the patterned nitroxide polymer brushes on a conducting substrate. Even though the organic radical polymer brushes provided a new approach to syn-thesize thin-film electrodes, they still existed many problems that needed to study and to figure out. We discussed the morphology and electrochemical performance about ni-troxide radical polymer in the thesis. In the measurement of surface properties, we used the contact angle, electron spectroscopy for chemical analysis (ESCA) and atomic force microscopic (AFM) to proceed. Another, in the measurement of electrochemical analysis, we used the cyclic voltammetry(CV), alternating current (AC) impedance and charge-discharge to understand the regarding mechanism in this polymer layer during the electrochemical reaction. In chapter 4, we discussed the oxidative problem in the polymer brushes. It should be well controlled during the oxidation reaction, because the oxidation level may affect the diffusion of electron that resulted the capacity better or not. In chapter5, we controlled the density of polymer brushes to construct the possible mechanism during the electro-chemical reaction, and found out the possible factors that affected the electrochemistry. In chapter 6, we applied the better results from the front chapter to the organic radical battery, and compared their electrical performance.

L'objectif des travaux est de démontrer que la lithographie douce, quelquefois baptisée " Micro-Contcat Printing (µCP)", constitue une méthode de dépôt de biomolécules présentant de nombreux avantages pour des applications de type Biopuces. Pour la fabrication de puces à ADN, nous démontrons que le µCP est une technique compétitive par rapport au dépôt robotisé de gouttes traditionnellement utilisé. Le coût est inférieur, la densité des puces est augmentée et la qualité et la définition des motifs biomoléculaires sont supérieures. Une étude complète des mécanismes d'encrage des timbres élastomères d'impression ainsi que des mécanismes de transfert par contact des molécules vers le substrat est présentée. Le rôle prépondérant des fragments de polymère non réticulés présents à la surface des timbres est mis en évidence. Dans un second volet nous étudions la possibilité de générer par la même méthode des puces à biomolécules uniques. Nous montrons comment le µCP peut être poussé jusqu'à une résolution sub-micrométrique proche de 50 nm. Deux voies technologiques originales impliquant la lithographie douce sont proposées : l'une pour peigner individuellement en des sites organisés précisément sur la surface des longs brins d'ADN pour des études de génétique, l'autre pour fixer des molécules individuelles d'ADN par une extrémité rendant possible l'étude dynamique de molécules uniques (ADN) sur de larges populations.

L’étude des propriétés singulières de nanoparticules colloïdales synthétisées par voie chimique et leur intégration dans des nano-composants requiert leur assemblage dirigé sur des zones parfaitement définies et localisées de surfaces solides. L’objet de cette thèse est le développement d’une méthode d’assemblage dirigé originale: la nanoxérographie par microscope à force atomique (AFM). Cette technique consiste à injecter localement, sur des zones spécifiques, des charges électrostatiques dans un matériau électret par l’intermédiaire d’une pointe d’AFM. Ces charges servent ensuite de pièges électrostatiques sur la surface pour les nanoparticules en solution. Dans le cadre de ce travail, l’injection, la rétention de charges dans de fines couches électrets de PolyMéthylMéthAcrylate (PMMA) et la quantification des densités de charges surfaciques des motifs chargés, ont été étudiées grâce au mode électrique dérivé de l’AFM, le microscope à force Kelvin (KFM). L’étude de l’assemblage de nanoparticules de différentes natures (métal, polymère (organique ou inorganique)), de taille moyenne variable dans un large domaine (2 nm - 1µm) et de potentiel zêta contrôlé a permis d’analyser les mécanismes de dépôt et de montrer les performances de la méthode et son aspect générique. Enfin deux techniques d’injection de charges parallèles ont été mises en place afin d’offrir des perspectives industrielles: le microcontact printing électrique et la nanoimpression électrique / The study of original properties of colloidal nanoparticles and their integration into nanodevices requires their assembly onto specific areas of solid surfaces. The aim of this thesis work is to develop an innovative method for the directed assembly of colloidal nanoparticles: the nanoxerography process by atomic force microscope (AFM). This technique consists in injecting charges into electrets using an AFM tip. The injected charges are then used to electrostatically trap nanoparticles from suspensions onto the surface. In this context, the charge writing and charge decay in PolyMethyMethAcrylate (PMMA) thin films were studied and the charge density of the charged patterns were quantified using Kelvin force microscope (KFM), an electrical mode of AFM. Assemblies of nanoparticles of different nature (metallic, polymeric (organic and inorganic)), with average sizes extending over a large range (2 nm to 1 µm) and controlled zeta potential were obtained on PMMA thin films. This allowed the analysis of assembly mechanisms and demonstration of the excellent performance of the method. Finally, two techniques of parallel charge writing, viz., the electrical microcontact printing and the electrical nanoimprinting were explored with the prospect of extending the nanoxerography process to industrial scale