Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (leaves 246-276).

La course à la compétitivité que se disputent les industriels du semi-conducteur implique d’augmenter le nombre de fonctionnalités par puce ainsi que de réduire leur coût unitaire, ce qui se traduit par une diminution continue de leur taille. Pour ce faire, le DSA (Directed Self-Assembly), ou auto-assemblage dirigé des copolymères à blocs associe les techniques de lithographie conventionnelle avec les propriétés d’organisation à l’échelle moléculaire des copolymères. Dans ce cadre, l’objectif global de cette thèse est d’évaluer le potentiel d’industrialisation du DSA par grapho-épitaxie pour des applications de type « shrink » et « multiplication » de contacts. Il s’agit en particulier de démontrer la capacité de cette technique à répondre au cahier des charges de l’ITRS en termes d’uniformité de CD, de désalignement et de taux de défauts. Une première étude concernant le « shrink de contact », basée sur l’impact des propriétés matériaux, d’affinité de surface et de tailles de guides permet de comprendre les mécanismes qui rentrent en jeu dans l’apparition de défauts d’assemblage. Une seconde partie de l’étude porte sur la multiplication de contact. Pour adresser cette application, deux types de guides ont été étudié : les guides elliptiques et les guides complexes dits « peanut ». L’étude de la fenêtre de procédé en termes de paramètres procédé comme le temps et la température de recuit, mais aussi de commensurabilité, a été menée. Une attention particulière a été portée sur l’impact de la variation du guide sur le pitch final obtenu en DSA, dont les données expérimentales ont été corrélées avec des résultats de simulation. Les critères de réussite sont basés sur les performances lithographiques qu’il faut juger à travers une métrologie de pointe. Le développement d’une métrologie spécifique pour mesurer l’erreur de placement des contacts ainsi que leur pitch a été conduite. / The competitiveness-chasing in which industrial manufactures are involved, leads to an exponential increase in the number of functionalities per chips, as well as reducing their unit cost, which results in a continuous decrease of their size. To achieve this, DSA (Directed Self-Assembly) of block copolymers, combines conventional lithography techniques with the molecular-scale organizational properties of copolymers. In this framework, the overall objective of this thesis is to evaluate the industrialization potential of the DSA process by graphoepitaxy for contact hole shrink and contact multiplication applications. In particular, it is necessary to demonstrate the ability of this technique to meet the ITRS specifications in terms of CD uniformity, misalignment and hole open yield. A first study on contact shrink, based on the impact of material properties, surface affinity and guiding feature size, allows us to understand the mechanisms involved in the appearance of defects. A second part of the study deals with contact multiplication. To address this application, two types of guides have been studied: elliptical guiding patterns and more complex ones called "peanut". The study of the process window in terms of process parameters such as annealing time and temperature, but also commensurability was conducted. Particular attention was paid to guide size variation and its impact on DSA final pitch. Experimental data from this study were correlated with simulations. The success criteria are based on the lithographic performances that must be judged through advanced metrology. The development of a specific metrology to measure the placement error of contacts as well as their pitch was conducted.

Supramolecular interactions are of great importance in the fabrication of new functional materials. In particular, colloidal assembly via supramolecular pathway has contributed to numerous innovations in material chemistry, on account of its specific, directional and dynamic non-covalent interactions. By taking advantage of the non-covalent supramolecular interactions, tailored complementary colloidal building blocks which are normally incompatible with each other could be integrated interdependently, forming novel hybrid materials with emerging properties. This thesis mainly focuses on the design, preparation and characterization of novel colloidal assemblies based on cucurbit[n]urils host-guest interactions, including hybrid ‘raspberry-like’ colloids, catalytic polymeric nanocomposites, advanced structured colloids, and supramolecular polymer colloidal hydrogel.

Le travail décrit dans cette thèse couvre une étude fondamentale sur des canaux artificiels d'eau et sur des matériaux membranaires incorporant ces canaux. Structuré en quatre chapitres, la thèse commence par une présentation de l'état de l’art sur les systèmes biomimétiques de transport d'eau et des membranes biomimétiques. Au centre de tous ces travaux de recherche sont les protéines biologiques hautement efficaces et sélectives, les Aquaporines. Le deuxième chapitre présente les canaux artificiels d'eau à base d'imidazole-quartet. Les similitudes structurelles et fonctionnelles avec les Aquaporines sont discutées et caractérisées par plusieurs méthodes expérimentales. Les structures à l'état solide obtenues à partir de monocristaux présentent une organisation très similaire des I-quartets avec leurs homologues biologiques. Le biomimétisme fonctionnel du transport de l'eau a été démontré par des expériences cinétiques de transport à travers des systèmes vésiculaires. Le mécanisme de translocation de l'eau et l'organisation confinée dans des environnements lipidiques a été confirmé par des simulations dynamiques moléculaires, tandis que la preuve physique de l'eau orientée dipolaire dans les canaux intégrés aux lipides a été fournie par des expériences de spectroscopie IR polarisée. Le troisième chapitre présente de nouveaux canaux d'eau artificiels en utilisant une stratégie d'auto-assemblage. De nouveaux composés à base de diol, de tétrazacrown et de tryarilamine capables de transporter l'eau sont décrits. Le dernier chapitre décrits le passage du niveau moléculaire aux matériaux membranaires macroscopiques incorporant des canaux d'eau artificiels. Deux configuration membranaires différentes ont été décrites: des membranes en couche mince par l'incorporation de nanoparticules à base d'imidazole dans des polymères de polyamide et des membranes de la cellulose régénérée chimiquement greffée par des monomères de canaux d'eau artificiels. Les membranes ont été caractérisées par diverses méthodes d'imagerie et d'analyse et leurs performances ont été testées dans des expériences d'osmose inverse et de filtration d'osmose directe. La thèse est conclue avec une partie de conclusion générale, comprenant des perspectives pour les développements futurs. / The work described in this thesis covers an in depth fundamental study of artificial water channels and of membrane materials incorporating these channels. Structured in four chapters, the thesis begins with a presentation of the state of the art in the field of biomimetic systems and membranes for water transport. The center of the described research work is the family of highly efficient and selective biological water transporter proteins, the Aquaporins. The second chapter presents the description of imidazole-quartet supramolecular artificial water channels. Structural and functional similarities with Aquaporins are discussed and based on several experimental methods. Single-solid state structures present very similar organization of confined water wires as found in their biological counterparts. Functional mimicry of water transport has been proved through stopped flow experiments in vesicular systems. Further characterization concerning water translocation mechanism and confined organization in lipid environments have been obtained through molecular dynamic simulations, while physical evidence of dipolar oriented water in lipid embedded channels has been provided by sum frequency generation experiments. The third chapter presents novel artificial water channels. New diol, tetrazacrown and tryarilamine based compounds have been described, with a main focus on design, synthesis, self-assembly and water transport properties. The last chapter makes the transition from the molecular systems to macroscopic membrane materials incorporating artificial water channels. Two different approaches have been described: thin film nanocomposite membranes based on the incorporation of imidazole-quartet nanoparticles in polyamide polymers and chemically grafted regenerated cellulose membrane through the use of custom monomers for the obtaining of artificial water channels. The membranes have been characterized through various imaging and analytical methods and their performances have been tested in reverse and forward osmosis experiments. The thesis is concluded with a general conclusion part, including perspectives for future developments.

Le Lanréotide est un octapeptide amphiphile cationique et un analogue thérapeutique de la somatostatine. Cette molécule synthétique a été conçue au sein de Beaufour-Ipsen comme thérapie contre l’acromégalie. Ce peptide révèle la propriété de former des nanotubes avec un haut degré de monodispersité en diamètre des tubes (244 Å) et épaisseur de la paroi (~18 Å) lorsqu’il est mélangé avec de l’eau pure à 10% (w/w). Le peptide forme des tubes emboîtés à plus haute concentration. Cette propriété d’auto-assemblage est utilisée pour concevoir un implant sous cutané à libération prolongée d’un mois : la Somatuline Autogel. Les gels de Lanréotide deviennent de plus en plus visqueux avec la concentration en peptide et cette viscosité limite la dose maximale injectable. L’ajout d’un adjuvant dans la formulation : le polyéthylène glycol (PEG600) à permit d’augmenter le temps de libération du peptide dans l’organisme tout en diminuant la viscosité du gel. Dans le but d’étudier l’effet du PEG600 sur l’auto-assemblage du Lanréotide, une étude structurale et thermodynamique est proposée. Cette étude est réalisée grâce à une approche par diagramme de phase systématique, par la technique de diffusion des rayons X et de modèles d’analyses des clichés, croisé par différentes techniques de caractérisations moléculaires. Cette étude révèle des interactions fortes du PEG avec le Lanréotide conduisant à la formation d’un complexe en solution. Ce complexe influe sur les équilibres entre deux phases du système biphasique, tube et intermédiaire du Lanréotide (rubans et dimères), ce qui pourrait jouer un rôle important dans les propriétés rhéologiques des gels. Enfin, il est montré qu’il est possible de réaliser la transition pratiquement totale du Lanréotide vers un dimère chimique conduisant à la formation de fibre type amyloïde. La simplicité du procédé de fabrication à température ambiante de ce dimère non actif dans l’organisme par un simple changement d’ordre d’addition des composants, fait de la compréhension des paramètres physico-chimiques de formations de ce dimère, un point capital du point de vue industriel. / The Lanreotide is an cationic octapeptide and a therapeutic analogue of the somatostatin. This synthetic molecule was designed by Beaufour Ipsen as a therapy against acromegaly. This peptide has the capacity to form monodisperse nanotubes with a high degree of monodispersity in diameter (244 Å) and wall thickness (~18 Å) when the peptide is mixed with pure water at 10% (w/w); embedded tubes are found at higher concentration. The viscosity of Lanreotide gels is strongly increasing with the peptide concentration, a property that limits the maximum injectable dose. The addition of a polymer (polyethylene glycol, PEG600) as an adjuvant in the formulation allows one to increase the release time in the organism to be treated and to decrease the gel viscosity. To study the effect of PEG600 on the self-assembly of the Lanreotide, a structural and thermodynamic work is proposed. This study is performed with a systematic phase diagram approach, by X-ray scattering and modeling of the scattering pattern and different experimental techniques at the molecular scale. This study reveals strong interaction between PEG and Lanreotide that form a complex in solution. This complex impacts the equilibrium state between two phases of the biphasic system, i.e., pure tubes and an intermediate state consisting of a mixture between ribbons and dimers of the Lanreotide. This result could play an important role for the gel’s rheological properties. Then, we demonstrate that it is possible to obtain an almost complete transition to a covalent dimer which yields the formation of amyloid fibers. To sum up, we discuss a new process for the fabrication of a dimer that is not active in the organism, this process being (i) based on a simple change of the order at which the components are added in solution and (ii) easy to implement at room temperature. Our findings could impact industrial applications.

xviii, 192 p. / Gold nanoparticles in the 1-2 mn core diameter size regime have generated a great deal of interest due to their size-dependent electronic, optical, and catalytic properties. A number of proof-of-concept experiments have demonstrated that small metal nanoparticles can be integrated into single electron transistors and optical waveguides. Still, reliable incorporation of gold nanoparticles into devices requires practical methods for their assembly on surfaces. Additionally, surface modification methods must be developed in order to control interparticle interactions and nanoparticle-environment interactions for use in sensing and catalysis. In this research, nanoparticle-substrate interactions were utilized to assemble surface-bound gold nanoparticle monolayers with interesting electronic and catalytic properties. Gold nanoparticles (1.5 nm diameter) with a thiol ligand shell containing phosphonic acid terminal functionality were synthesized and assembled selectively onto hafnium-modified silicon dioxide substrates through bonding of the terminal phosphonate to Hf(IV) surface groups. By increasing the surface coverage of Hf, it was possible to assemble monolayers of gold nanoparticles dense enough to exhibit nonlinear current-voltage properties across a 5-μm electrode gap at room temperature. Moreover, by taking advantage of the selectivity of this ligand shell for ZnO over SiO 2 , small gold nanoparticles were utilized as catalysts for selective growth of patterned, vertical ZnO nanowire arrays. In addition to engineering nanoparticle-substrate interactions, new surface modification methods were introduced to manipulate the interaction of the as-deposited gold nanoparticle monolayers with the environment. For example, thiol-thiol ligand exchange reactions were carried out on the surface-bound nanoparticle monolayers by immersion in dilute thiol solutions. Contact angle and XPS measurements indicate that the upper, surface-exposed phosphonic acid ligands are replaced by incoming thiol ligands. TEM measurements indicate that nanoparticle monolayers remain surface-bound and are stable to this exchange process, as the average particle size and surface coverage are preserved. As another example, the ligand shell can be partially removed by UV/ozone treatment to expose bare gold cores to the surrounding environment. On metal oxide substrates, this approach activates the particles for room temperature oxidation of carbon monoxide to carbon dioxide. This dissertation includes both my previously published and my co-authored materials. / Adviser: James E. Hutchison

xx, 162 p. ; ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / In this thesis we theoretically and experimentally investigate the subwavelength manipulation of light with nano-scale patterned metallodielectric resonators. By coupling light to surface plasmon excitations, we calculate the modified dispersion relation of the resulting surface plasmon polariton (SPP) modes in two types of subwavelength resonators: (i) closed, spherical micro-resonators with nano-scale metal-dielectic-metal shells; (ii) periodic, metal-dielectric-metal-layered silica surfaces. We show theoretically that with the proper geometric parameters, one can use sub-wavelength structure on spherical surfaces to manipulate the SPP dispersion relation in a highly tunable fashion. A tunable avoided-crossing of plasmonic dispersion bands is found to be the result of the coherent near-field coupling of silver nano-shell SPP modes. By developing our own stable computational algorithms, we calculated the far-field scattering of these metal-dielectric-metal layered micro-resonators. We demonstrate that the near-field interaction of the SPPs leads to a tunable, SPP induced transparency in the composite particle's scattering and extinction cross-sections. Utilizing finite element calculations, periodically-modulated metal-dielectric-metal layers are shown to alter the transmission properties of plasmon enhanced transmission through their support of interior surface plasmon (ISP) modes. Our simulations indicate that, subwavelength silver-silica-silver trilayers coating arrays of silica cylinders support ISP modes analogous to those found in spherical metal-dielectric-metal shells. We examine the coupling between ISP and radiating SPPs, and find the possibility of efficient free-space coupling to ISP modes in planar geometries. Further, the excitation of these ISP modes is found to predicate plasmon enhanced transmission, adding directionality and refined frequency selection. Experimentally, we show that self-assembled monolayers of silica spheres form a novel substrate for tunable plasmonic surfaces. We have developed a deposition method to conformally coat these hexagonal-close-packed substrates with nano-scale silver-polystyrene-silver coatings. We use angle-resolved spectroscopy to study their transmission properties. We have discovered that the presence of the silver-polystyrene-silver layer supports the excitation of ISP modes, and that these excitations significantly alter the plasmon enhanced transmission. Finally, we have discovered that the use of the ordered monolayers as a plasmonic substrate can create a new effect in conjunction with plasmon enhanced transmission: directionally asymmetric transmission. This is demonstrated with optically thick silver coatings evaporated upon onto the ordered sphere monolayers. / Adviser: Miriam Deutsch

xvii, 147 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / Supramolecular chemistry is a relatively new and exciting field offering chemists simplistic approaches to generating complex assemblies through strategically designed ligands. Much like the many spectacular examples of supramolecular assemblies in nature, so too are chemists able to construct large, elegant assemblies with carefully designed ligands which bind preferentially to target metal ions of choice. An important concept of supramolecular chemistry, often subtle and overlooked, is secondary bonding interactions (SBIs) which in some cases, act as the glue to hold supramolecular assemblies together. This dissertation examines SBIs in a number of systems involving the pnictogen elements of arsenic and antimony as well as aromatic interactions in self-assembled monolayers. The first half of this dissertation is an introduction to the concepts of supramolecular chemistry and secondary bonding interactions and how they are used in the self-assembly process in the Darren Johnson laboratory. Chapter I describes how secondary bonding interactions between arsenic and aryl ring systems and antimony and aryl ring systems assist with the assembly process. Chapter II is a continuation of the discussion of SBIs but focuses on the interactions between arsenic and heteroatoms. The second half of this dissertation will describe work performed in collaboration with Pacific Northwest National Laboratory (PNNL) in Richland, WA. This work was performed under the guidance of Dr. R. Shane Addleman in conjunction with Professor Darren W. Johnson of the University of Oregon. This portion describes novel systems for use in heavy metal ion remediation from natural and unnatural water sources. Chapters III-V describe functionalized mesoporous silica for use in heavy metal uptake from contaminated water sources. Chapter V describes a new technology invented during this internship at PNNL which utilizes weak bonding interactions between aryl ring systems to produce regenerable green materials for toxic metal binding. This work is ongoing in the Darren Johnson lab. This dissertation includes my previously published and co-authored material. / Committee in charge: Michael Haley, Chairperson, Chemistry; Darren Johnson, Member, Chemistry; Shih-Yuan Liu, Member, Chemistry; James Hutchison, Member, Chemistry; Eric Johnson, Outside Member, Biology

Making use of the non-covalent bond to make materials is of great interest in many fields of research. This PhD thesis describes a variety of highly interdisciplinary research undertaken at the interface between chemistry, materials science, physics and engineering. Chapter 1 is an introductory chapter into the core concepts underlying this thesis. Supramolecular chemistry as a broad research field is briefly reviewed, followed by a focus on host-guest chemistry. The macrocyclic cucurbit[n]urils (CB[n]s) in particular are highlighted with a discussion on their recent applications since their discovery. Emulsions and their controlled generation with microfluidic techniques are then reviewed, as they have been used as templates for self-assembly processes throughout this thesis. A study into the synthesis of extended polymer networks composed entirely from small molecules held together by non-covalent interactions is described in Chapter 2. These highly dynamic and responsive supramolecular polymer networks have not yet been constructed with CB[n] host-guest chemistry. The ability of the larger CB[8] macrocycle to encapsulate multiple guest molecules in a stepwise fashion was taken advantage on in designing the synthesis of branching monomers. The monomers had two (A$_2$) or three (B$_3$) terminal guest moieties for CB[8], which upon combination formed branching supramolecular polymers that were multi-stimuli responsive. However, the polymers precipitated from solution at high concentrations rather than form a cross-linked network, due to competing intra-chain cyclisation and the limited water solubility of CB[8]. By confining these polymers to microfluidic droplets, directed assembly to the liquid-liquid interface could drive polymerisation to form an interfacial cross-linked gel that was both elastic and self-healing. Chapter 3 follows on from these results, describing attempts into constructing hyperbranched supramolecular polymers from an AB$_2$ guest molecule and CB[8] that would form globular polymers. Intramolecular complexation dominated with the guest molecules synthesised (A and B complexing within the molecule), evidenced by a variety of characterisation. Compared to previous works that relied on linear molecules to form a folded conformation for intramolecular complexes, these molecules were pre-organised with a unique cooperative complexation pathway. The stimuli-responsiveness of the complexes was probed, and the formation of self-sorting mixtures was demonstrated with multiple CB[n] and additional guest molecules. Controlling the self-assembly of semi-conducting nanocrystals with CB[7] is detailed in Chapter 4, a process that typically requires harsh conditions or extensive time-scales. Semi-conducting nanocrystals could be assembled instantaneously from water into extended networks that were highly porous with excess CB[7], retaining their nanoscale properties. Limiting quantities of CB[7] could then form nanoscale aggregates that remained in solution. Confinement of these assemblies within microfluidic droplets allowed the synthesis of dense microparticles, that retained their shape after re-dispersal in water. By simply including metallic nanocrystals as a minor component, mixed aggregates could be synthesised analogously. Finally, Chapter 5 draws overall conclusions from the results of this thesis, looking broadly at the potential for future prospects in these areas of research.

Lithium-ion batteries (LIBs) are an integral part of consumer electronic devices and electric vehicles. There is a growing need for LIBs with higher capacity, rate performance and cycling stability. At the anode electrode these challenges are being addressed for instance by utilising materials with higher theoretical capacity compared to graphite (372 mAh/g) or by optimising the morphology of materials through nanostructuring of the electrode. In this thesis the former is investigated by synthesising a reduced graphene oxide (rGO) tin sulphide (SnS2) hybrid, and the latter by self-assembly of rGO sodium titanate and rGO titanium dioxide (TiO2) nanorods. In Chapter 2, SnS2 is investigated due to its high theoretical capacity as an anode material (645 mAh/g), low cost and environmental benignity. SnS2 nanoparticles were grown directly on rGO sheets which provide a conductive framework and limit the detachment of tin particles which undergo large volume changes during alloying reactions. However, a fast decrease in capacity was observed. Post-mortem analysis of the electrodes showed that rGO becomes irreversibly passivated suggesting that additional measures to retain effective charge transport between the low weight percent conductive additive and the active phase during cycling are required. An alternative material system based on nanorods of intercalation materials (sodium titanate and TiO2) wrapped by rGO sheets was chosen to investigate self-assembly in anodes to address the low packing density of nanomaterials. A drop-casting method was used to align rGO-sodium titanate nanorods through evaporation driven self-assembly (Chapter 3) which relies on a combination of electrostatic repulsive forces originating from the rGO coating, and liquid crystal phase formation at high concentrations, facilitated by the high aspect ratio nanorods. As reference, non-aligned films were prepared by adjusting the pH of the nanorod dispersion. Freestanding aligned and non-aligned films were converted to rGO-TiO2 (Chapter 4). The volumetric capacity of the self-assembled films was double that of non-aligned films, and up to 4.5 times higher than traditional casted electrodes using the same material. Further, up to rates of 4 C, the self-assembled films outperformed the non-aligned films. These films showed no sign of capacity fading up to 1000 cycles, which together with post-mortem analysis confirms that these assembled structures are maintained during battery cycling.