Dissertations / Theses on the topic '3D patterning'

Additive manufacturing in the form of 3D printing is a revolutionary technology that has developed within the last two decades. Its ability to print an object with accurate features down to the micro scale have made its use in medical devices and research feasible. A range of life-saving technologies can now go from the laboratory and into field with the application of 3D-printing. This technology can be applied to medical diagnosis of patients in at-risk populations. Living biosensors are limited by being Genetically Modified Organisms (GMOs) from being employed for medical diagnosis. However, by containing them within a 3D-printed enclosure, these technologies can serve as a vehicle to translate life-saving diagnosis technologies from the laboratory and into the field where the lower cost would allow more people to benefit from inexpensive diagnosis. Also, the GMO biosensors would be contained with a press-fit, ensuring that the living biosensors are unable to escape into the environment without user input. In addition, 3D-printing can also be applied to reduce the cost of lab-based technologies. Cell patterning technology is a target of interest for applying more cost-effective technologies, as elucidation of the variables defining cell patterning and motility may help explain the mechanics of cancer and other diseases. Through the use of a 3D-printed stamp, bacterial cells can be patterning without the use of a clean room, thus lowering the entry-barrier for researchers to explore cell patterning. With the commercialization of 3D-printing an opportunity has arisen to transition life-saving technologies into more cost-effective versions of existing technologies. This would not only allow more research into existing fields, but also to ensure that potentially life-saving technologies reach the people that need them.
Ph. D.

PGSm was synthesized, and characterized chemically and mechanically. Porous PGSm was photocured into 3D foams. PGSm was printed via microstereolithography into nerve guidance conduits and tested for use in peripheral nerve repair in vitro, ex vivo and in vivo. Porous PGSm conduits were developed and tested ex vivo, with an intended use for larger gap injuries. Porous PGSm was developed into tunable microparticles and explored for use as a cartilage tissue-engineering scaffold. The polyHIPE was also developed as an in vitro neuronal model and a scaffold for ESCs. Results show the material was developed into a photocurable polymer, capable of being 3D printed into highly accurate NGCs. PGSm conduits performed well overall and regeneration into the distal stump was witnessed in vivo. Techniques were developed to photocure reproducible porous polyHIPE conduits, with promising initial in vitro/ex vivo results. Porous microparticles were seen to allow for the development of cartilage like tissue in vitro. Porous PGSm was used for neuronal models and stem cell scaffolds. In summary the developed PGSm is useful for simple and complex scaffolds for soft tissue engineering.

L’organisation de Nanoparticules (NPs) sur des motifs complexes structurés en 3D est un challenge d’actualité. Une telle nanostructuration devrait donner lieu à des propriétés collectives permettant l’émergence de très nombreuses applications originales. Dans ce contexte, le contrôle de l’organisation des NPs plasmoniques en 3D est une approche prometteuse pour augmenter le nombre de « points chauds » électromagnétiques et proposer ainsi une nouvelle génération de capteurs intégrés et ultrasensibles. Dans cette thèse, nous proposons un procédé universel pour assembler des NPs et plus particulièrement d'or sur des motifs polymères structurés en 1D et 3D. La méthode implique la fonctionnalisation d’un photopolymère et sa structuration à 2 photons afin d’attirer de manière spontanée des NPs colloïdales et permettre ainsi leur organisation précise au sein même de certaines microstructures 3D complexes. Nous montrons en particulier la possibilité d’organiser des NPs d’or sous forme de monocouche sans aucune agrégation sur la surface du polymère tout en contrôlant leur localisation et densité. Nous étudions le mécanisme de fonctionnalisation de notre photopolymère et d’interaction des microstructures polymérisées avec les NPs et montrons la possibilité d’étendre cette approche prometteuse à plusieurs types de NPs. Finalement, nous illustrons le potentiel d’application de notre approche à travers, notamment, la détection de molécules organiques grâce à l’effet SERS
The precise patterning of nanoparticles (NPs) with fine control of their spatial positioning and orientation is highly desirable. Their selective assembly in multiple dimensions and on continuous length scales would lead for the formation of collective properties that differ from those of individual particles providing astronomical potential to many applications. In this context, the 3D patterning of metallic NPs offer the potential to increase the number of electromagnetic “hot spots” towards new generation of integrated and ultrasensitive sensors. In this thesis, we present a general strategy for the immobilization of NPs, particularly gold, on 1D and 3D polymer micro templates. This strategy involves the functionalization of photopolymers and their 2-photon polymerization to fabricate microstructures that selectively attract colloidal NPs with suitable ligands allowing their precise organization even within complex 3D structures. We show monolayers of NPs without aggregations collecting a clean surface besides that the surface density of NPs on the polymer surface can be controlled. We deeply investigated the functionalization mechanism of photopolymer and the interaction of the polymer surface with NPs. Finally, we show the potential of our functionalization strategy for multiple applications including SERS detection of chemicals

The ability to control stem cell functions, particularly neuronal progenitors, has long since been believed to be the key to successful treatment of neurodegenerative disorders such as Alzheimer's, Parkinson's and accidents involving head trauma. The neurology field calls for many new solutions to address the controlled neural stem cell seeding and placement of cells for neural tissue regeneration. Self-assembled monolayers (SAM) from the alkanethiol group provide a straightforward applicable, reliable treatment for cell adhesion. An ODT/gold treatment was used to adhere the cells to patterned areas, due mainly to a high confluence of cells attracted to it, as well as the viable environment it produced for the cells. Arrays of micropillars, made of SU-8 photoresist, then covered with a thin film of gold and treated with the ODT, created scaffolding allowing manipulation of neural stem cells. Based on multiple trials of observing varying cross-sectional geometric parameters, metal layer thicknesses and the ODT/Gold treatment, this study explores seeding density control, base and circumferential cell population dependence on those parameters.
M.S.M.E.
Department of Mechanical, Materials and Aerospace Engineering;
Engineering and Computer Science
Mechanical Engineering MSME

Cette thèse explore l'utilisation de données multi-échelles pour modéliser une représentation tridimensionnelle (3D) et générer un registre numérique complet d'un assemblage de fossiles contenant des hominines à partir de l'unité lithostratigraphique P à Kromdraai situé dans le " berceau de l'humanité " classé au patrimoine mondial par l'UNESCO (Province de Gauteng, Afrique du Sud). Les objectifs principaux de cette recherche sont d'illustrer en 3D la progression temporelle et spatiale des fouilles de Kromdraai sur la période 2014-2018, d'analyse la distribution spatiale des vestiges d'homininés et de faune, comme des outils, et finalement, de fournir une documentation sur le patrimoine archéologique de Kromdraai. Nous avons réalisé une analyse multi-scalaire du site, avec l'application de méthodes de photogrammétrie terrestre et aérienne. Conformément aux principes et directives de la gestion du patrimoine archéologique mandatés par les agences internationales telles que l'UNESCO, nous présentons également un protocole de documentation du patrimoine. Nous avons utilisé des technologies de capture de données 3D pour numériser le site de Kromdraai et ses éléments archéologiques découverts entre 2014 et 2018 lors des fouilles. Cette recherche présente une technique originale développée pour la visualisation et la quantification des sédiments volumiques prélevés sur le site à chaque période de fouille par chaque fouilleur. Les estimations de volume calculées à l'aide de la photogrammétrie 3D fournissent un contexte temporel et spatial des sédiments prélevés lors des fouilles successives, et permettent un repositionnement virtuel et plus précis des vestiges découverts ex situ. De plus, nous avons mis en place une modélisation des métadonnées pour démontrer l'utilisation d'un système de gestion de base de données 4D pour la fusion, l'organisation et la diffusion de l'ensemble des données du site de Kromdraai et le partage de la propriété intellectuelle. Nous introduisons également l'une des premières approches statistiques de la modélisation spatiale 3D dans un site Plio-Pléistocène porteurs d'hominines en en Afrique du Sud. En mettant en œuvre des méthodes classiques de tests statistiques telles le partitionnement de données spatiales 3D, nous avons étudié les modèles de l'assemblage de fossiles dans l'unité P, ainsi qu'un échantillon de 810 spécimens catalogués entre 2014 et 2018. Le regroupement de bovidés, de carnivores, d'homininés et de primates non humains a révélé un modèle de distribution spatiale non uniforme des fossiles in situ. Cette recherche présente des méthodes précieuses qui peuvent être appliquées à d'autres sites fossiles contenant des hominines dans le berceau de l'humanité. Ces méthodes peuvent être appliquées pour documenter une fouille archéologique et reconstruire un site en 3D, ainsi que pour documenter des informations patrimoniales. Nos résultats permettent d'améliorer l'interprétation des assemblages fossiles à l'aide d'analyses basées sur des modèles 3D au sein d'un assemblage contenant des hominines
This thesis uses multi-scalar data to create a three-dimensional (3D) representation and, to generate a complete digital record of the early hominin-bearing fossil assemblage from the lithostratigraphic Unit P at Kromdraai in the Cradle of Humankind World Heritage Site (Gauteng Province, South Africa). The main purposes of this research were to illustrate in 3D the temporal and spatial progression of the excavations at Kromdraai since 2014, to investigate the spatial distribution of the hominin, faunal assemblages and artefacts, and ultimately, to provide an archive documenting the archaeological heritage of Kromdraai. We provided a multi-scalar analysis of various aspects of the study site, with the application of methods such as multi-image land and aerial photogrammetry. In alignment with the principles and guidelines for the management of archaeological heritage mandated by international agencies such as UNESCO, we also present a protocol for heritage documentation. We used 3D data capture technologies to record the Kromdraai site and the archaeological evidence discovered between 2014 and 2018 from its main excavation. This research presents an original technique developed for the quantification and visualization of the volume sediments removed from the site during each excavation period. Volume estimations computed using 3D photogrammetry and digitization, provided a temporal and spatial context to the volume and location of material removed by each excavator and, a more precise and virtual repositioning of the fossil material discovered ex situ. Furthermore, we implemented metadata modelling to demonstrate the use of 4D relational database management systems for the fusion, organisation and dissemination of the Kromdraai site dataset and the sharing of intellectual property. We also introduce one of the first statistical approaches of 3D spatial patterning in Plio-Pleistocene early hominin-bearing assemblages in South Africa. Implementing classic statistical testing methods such as k-means and Density-Based Spatial Clustering and Application with Noise (DBSCAN) cluster computation in 3D, we investigated the spatial patterns of the fossil assemblage within Unit P, a sample of 810 individually catalogued specimens recovered between 2014 and 2018. The clustering of bovids, carnivores, hominins, and non-human primates revealed a non-uniform spatial distribution pattern of fossils in-situ. This research presents valuable methods that can be applied at other hominin-bearing fossil sites within the Cradle of Humankind to document an archaeological excavation and to reconstruct of the site in 3D, to document heritage information, and to enhance the interpretation of the fossil assemblages using evidence-based assessment of spatial patterns within a hominin-bearing assemblage

Three-dimensional biomolecule patterned hydrogels provide cellular microenvironments that mimic in vivo conditions. We are particularly interested in the fabrication of materials to spatially control stem cell differentiation towards the creation of tissue analogues. To this end, we have designed a 3D protein patterning system where differentiation factors were immobilized within distinct volumes through two-photon chemistry, which provides 3D control since the excitation volume is limited to the focal point of the laser. Agarose hydrogels were modified with 6-bromo-7-hydroxy-coumarin (Bhc) protected amines or thiols, which upon two-photon excitation are deprotected in defined volumes yielding reactive amines or thiols. Fibroblast growth factor-2 (FGF-2) was immobilized onto agarose-thiol-Bhc through either disulfide bond formation with agarose thiols or the physical interaction between human serum albumin (HSA) and the albumin binding domain (ABD). The use of biological binding pairs also provides mild immobilization conditions, minimizing the risk for bioactivity loss. Similarly, two differentiation factors for retinal stem progenitor cells were simultaneously immobilized: 1) ciliary neurotrophic factor (CNTF); and 2) N-terminal sonic hedgehog (SHH). Maleimide modified binding proteins, such as maleimide-streptavidin; react with exposed thiols, yielding 3D patterns of covalently immobilized streptavidin in agarose hydrogels. Growth factors are then introduced as fusion proteins with binding domains, such as biotin-CNTF, for complexation and thus 3D immobilization. By combining multiple binding systems with two-photon patterning, we were able to simultaneously 3D immobilize proteins towards the creation biomimetic hydrogels.

碩士
國立臺北科技大學
資訊工程系
107
Before 3D human model has been widely in industries such as medical, gaming, and fashion industry. The industries are only using 2D images for 3D modeling. But human is not like mechanical parts, it is hard to modeling human for information only from 2D drawings. Instead of only using 2D images to build 3D model, adding point cloud space element can fulfill the missed information for 3D modeling. This research is using point cloud to build 3D human model, and use the 3D human model to get the design measurements for cloth pattern design. By automation the fitting, measuring and drawing process, it expedite the product development timing and save the labor cost. The automation system in this research has three parts, 3D human modeling, 3D human measure and automatic patterning. To build a human model, this research use depth camera 3D scanning technology to get the point cloud data. Then import the point cloud data as OBJ and PLY format. Second part, restructure the point cloud data by filtering, normalization through Point Cloud Library(PCL). Last step of human modeling is convert data from voxel to inch as fitting measurement. Third part of the system is automated the patterning process. Covert the measurement data from 3D human modeling through OpenCV and use the converted data as design parameters to create pattering layout follow the design book equation. Finally, after fine tune the parameter data by designer, the pattering sketch will be after-processing to be printable in A4 size.

博士
國立清華大學
奈米工程與微系統研究所
99
Nanotechnology has been developed as a reliable technology for producing minimal components to perform more precise functions. In particular, the availability of nanolithography and nanostructure fabricating processes is important in the fields of photonics, electronics, biotechnology, and metamaterial. In our research, we present a generic and efficient chemical patterning method, compared with conventional photolithography this approach is without diffraction limit. Base on this approach, we expand a method for synthesizing three-dimensional (3D) gold and silver nanoparticle supercrystal films. Since nanoparticles have unique properties of surface plasmon, this technology will offer a pathway to designer plasmonic metamaterials. We fabricate chemical pattern based on local plasma-induced conversion of surface functional groups on self-assembled monolayers. Here, spatially controlled plasma exposure is realized by elastomeric poly(dimethylsiloxane) (PDMS) contact masks or channel stamps with feature sizes ranging from nanometer, micrometer, to centimeter, and an achievable resolution is down to the 50 nm range. This chemical conversion method has been comprehensively characterized by a set of techniques, including contact angle measurements, X-ray photoelectron spectroscopy (XPS), scanning photoelectron microscopy (SPEM), scanning electron microscopy (SEM), and scanning Kelvin probe microscopy (SKPM). In particular, XPS and SPEM can be used to distinguish regions of different surface functionalities and elucidate the mechanism of plasma-induced chemical conversion. Based on plasma-induced conversion, we expand a simple and efficient method for synthesizing large-area (>cm2), three-dimensional (3D) gold and silver nanoparticle supercrystal films. In this approach, Janus nanoparticle (top face solvent-phobic and bottom face solvent-philic) films with an arbitrary number of close-packed nanoparticle monolayers can be formed by using layer-by-layer (LbL) assembly from suspensions of thiolate-passivated gold or silver colloids. Furthermore, we demonstrate that these films can act as true 3D plasmonic crystals with strong transverse (intralayer) and longitudinal (interlayer) near-field coupling. In contrast to conventional polyelectrolyte-mediated LbL assembly processes, this approach allows multiple longitudinal coupling modes with a conspicuous spectral dependence on the layer number. We have found a universal scaling relation between the spectral position of the reflectance dips related to the longitudinal modes and the layer number. This relation can be understood by the presence of a plasmonic Fabry-Pérot nanocavity along the longitudinal direction, allowing the formation of standing plasmon waves under plasmon resonance conditions. The realization of 3D plasmonic coupling enables broadband tuning of collective plasmon response in a wide spectral range (visible and near-infrared) and a key pathway to designer plasmonic metamaterials.

As nanometer Very Large Scale Integration (VLSI) demands more transistor density to fabricate multi-cores and memory blocks in a limited die size, many researches have been performed to keep Moore's Low in two different ways: 2D geometric shrinking and 3D vertical wafer stacking. For the geometric shrinking, nano patterning with 193nm lithography equipment is one of the most fundamental challenges beyond 22nm while the next-generation lithography, such as Extreme Ultra-Violet (EUV) lithography still faces tremendous challenges for volume production in the near future. As a practical solution, Double Patterning Lithography (DPL) has become a leading candidate for sub-20nm lithography process. Another approach for multi-core integration is 3D wafer stacking with Through Silicon Via (TSV). Computer-Aided-Design (CAD) approaches to enable robust DPL and TSV technology are the main focus of this dissertation. DPL poses new challenges for overlay and layout decomposition. Therefore, overlay induced variation modeling and efficient decomposition for better manufacturability are in great demand. Since the variation of metal space caused by overlay results in coupling capacitance variation, we first model metal spacing variation with individual overlay sources. Then, all overlay sources are considered to determine the worst timing with coupling capacitance variation. Non-parallel pattern caused by overlay is converted to parallel one with equivalent spacing having the same delay to be applicable of a traditional RC extraction flow. Our experiments show that the delay variation due to overlay in DPL can be up to 9.1%, and well decomposed layout can reduce the variability. For DPL layout decomposition, we propose a multi-objective and flexible framework for stitch minimization, balanced density, and overlay compensation, simultaneously. We use a graph theoretic algorithm for minimum stitch insertion and balanced density. Additional decomposition constraints for overlay compensation are obtained by Integer Linear Programming (ILP). Robust contact decomposition can be obtained with additional constraints. With these constraints, global decomposition is performed using a modified Fiduccia-Mattheyses (FM) graph partitioning algorithm. Experimental results show that the proposed framework is highly scalable and fast: we can decompose all 15 benchmark circuits in five minutes in a density balanced fashion, while an ILP-based approach can finish only the smallest five circuits. In addition, we can remove more than 95% of the timing variation induced by overlay for tested structures. Three-dimensional integration has new manufacturing and design challenges such as device variation due to TSV induced stress and timing corner mismatch between different stacked dies. Since TSV fill material and silicon have different Coefficients of Thermal Expansion (CTE), TSV causes silicon deformation due to different temperatures at chip manufacturing and operating. Therefore, the systematic variation due to TSV induced stress should be considered for robust 3D IC design. We propose systematic TSV stress aware timing analysis and show how to optimize layout for better performance. First, a stress contour map with an analytical radial stress model is generated. Then, the tensile stress is converted to hole and electron mobility variations depending on geometric relations between TSVs and transistors. Mobility variation aware cell library and netlist are generated and incorporated in an industrial timing engine for 3D-IC timing analysis. TSV stress induced timing variations can be as much as 10% for an individual cell. As an application for layout optimization, we can exploit the stress-induced mobility enhancement to improve timing on critical cells. We show that stress-aware perturbation could reduce cell delay by up to 14.0% and critical path delay by 6.5% in our test case. Three-dimensional Clock Tree Synthesis (3D CTS) is one of the main design difficulties in 3D integration because clock network is spreading over all tiers. In 3D CTS, timing corner mismatch between tiers is caused because each tier is manufactured in independent process. Therefore, inter-die variation should be considered to analyze and optimize for paths spreading over several tiers in 3D CTS. In addition, mobility variation of a clock buffer due to stress from TSV can cause unexpected skew which degrades overall chip performance. Therefore, we propose clock period optimization to consider both timing corner mismatch and TSV induced stress. In our experiments, we show that our clock buffer tier assignment reduces clock period variation up to 34.2%, and the most of stress-induced skew can be removed by our stress-aware CTS. Overall, we show that performance gain can be up to 5.7% with the proposed CTS algorithm. As technology scaling continues toward 14nm and 3D-integration, this dissertation addresses several key issues in the design-manufacturing interface, and proposes unified analysis and optimization techniques for effective design and manufacturing integration.
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