Дисертації з теми "Nanofabrication, growth and self assembly"
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Zin, Melvin T. "Self-assembly and nanofabrication approaches towards photonics and plasmonics /." Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/15502.
Повний текст джерелаJung, Yeon Sik. "Templated self-assembly of siloxane block copolymers for nanofabrication." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/52791.
Повний текст джерелаThis electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student submitted PDF version of thesis.
Includes bibliographical references.
Monolayer patterns of block copolymer (BCP) microdomains have been pursued for applications in below sub-30 nm nanolithography. BCP selfassembly processing is scalable and low cost, and is well-suited for integration with existing semiconductor fabrication techniques. The two critical issues are how to obtain reliable long-range ordering of features with minimum defect densities and how to successfully transfer the patterns into other functional materials. Exceptionally well-ordered and robust nanoscale patterns can be made from poly(styrene-b-dimethylsiloxane) (PS-PDMS) BCPs, which have a very large Flory-Huggins interaction parameter between the blocks compared to other commonly used BCPs. Cylinder- or sphere-forming BCP films were spincoated over silicon substrates patterned with shallow steps using optical lithography or nanoscale posts made by electron-beam lithography, and solvent-annealed to induce ordering. This generates patterns with a correlation length of at least several micrometers. The annealed film was treated with plasma to obtain oxidized PDMS patterns with a lateral dimension of 14 - 18 nm. These can be used as an etch mask or an easily removable template for patterning functional materials. Solvent vapor treatments can tune the pattern dimension and morphology. Different degrees of solvent uptake in BCP films during solvent-annealing can manipulate the interfacial interaction between the two blocks, and a mixed solvent vapor can change the effective volume fraction of each block. The self-assembled patterns can be transferred into various kinds of functional materials.
(cont.) For example, arrays of parallel lines were used as a mask to pattern poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) conducting polymer thin films. The resulting PEDOT:PSS nanowire array was used as an chemiresistive-type ethanol-sensing device. Metallic films such as Ti, Pt, Ta, W, and magnetic Co and Ni were structured using a pattern-reversal process. Coercivity enhancements were observed for the fabricated ferromagnetic nanostructures such as wires, rings, and antidots. These functional nanostructures can be utilized for a variety of devices such as high-density and high performance sensor or memory devices.
by Yeon Sik Jung.
Ph.D.
Do, Hyung Wan. "Three-dimensional nanofabrication by electron-beam lithography and directed self-assembly." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/93778.
Повний текст джерелаThis electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references.
In this thesis, we investigated three-dimensional (3D) nanofabrication using electron-beam lithography (EBL), block copolymer (BCP) self-assembly, and capillary force-induced self-assembly. We first developed new processes for fabricating 3D nanostructures using a hydrogen silsesquioxane (HSQ) and poly(methylmeth-acrylate) (PMMA) bilayer resist stack. We demonstrated self-aligned mushroom-shaped posts and freestanding supported structures. Next, we used the 3D nanostructures as topographical templates guiding the self-assembly of polystyrene-b-polydimethylsiloxane (PS-b-PDMS) block copolymer thin films. We observed parallel cylinders, mesh-shaped structures, and bar-shaped structures in PDMS. Finally, we studied capillary force-induced self-assembly of linear nanostructures using a spin drying process. We developed a computation schema based on the pairwise collapse of nanostructures. We achieved propagation of information and built a proof of concept logic gate.
by Hyung Wan Do.
S.M.
Perl, András. "Multivalent self-assembly at interfaces from fundamental kinetic aspects to applications in nanofabrication /." Enschede : University of Twente [Host], 2008. http://doc.utwente.nl/60316.
Повний текст джерелаGates, Elisabeth Pound. "Self-Assembled DNA Origami Templates for the Fabrication of Electronic Nanostructures." BYU ScholarsArchive, 2013. https://scholarsarchive.byu.edu/etd/4000.
Повний текст джерелаPinto, Gómez Christian. "Directed self-assembly of block copolymers for the fabrication of nanomechanical structures." Doctoral thesis, Universitat Autònoma de Barcelona, 2021. http://hdl.handle.net/10803/671972.
Повний текст джерелаEl principal objetivo de esta tesis, titulada "Autoensamblaje dirigido de copolímeros de bloque para la fabricación de estructuras nanomecánicas", es demostrar la posibilidad de fabricar estructuras nanomecánicas funcionales mediante el autoensamblaje dirigido (DSA) de copolímeros de bloque (BCPs) como técnica de nanoestructuración. El DSA es una técnica de nanolitografía bottom-up basada en la capacidad que tienen los BCPs de segregarse en dominios de escala micro/nanométrica. Gracias a su alta resolución, alto rendimiento y bajo coste, esta técnica ha sido muy estudiada por la industria de semiconductores para nanoelectrónica, pero también ha sido aplicada en otros campos que requieren de una alta densidad de elementos a escala nanométrica. En esta tesis presentamos un proceso novedoso basado en DSA que demuestra ser apto para la fabricación de sistemas nanomecánicos. Demostramos la fabricación de membranas de silicio suspendidas ancladas por matrices de gran número de nanohilos de silicio empleando la grafoepitaxia de poliestireno-b-polimetilmetacrilato (PS-b-PMMA), uno de los BCP más extendidos. Los dispositivos obtenidos pueden desarrollarse para construir sensores de masa de alta sensibilidad basados en resonadores nanomecánicos.
The main goal of this dissertation, entitled "irected self-assembly of block copolymers for the fabrication of nanomechanical structures", is to demonstrate the possibility of fabricating nanomechanical functional structures by employing the directed self-assembly (DSA) of block copolymers (BCPs) as a nanopatterning tool. DSA is a bottom-up nanolithography technique based on the ability of BCPs to segregate into domains at the micro/nanoscale, and it has attracted high interest due to its inherent simplicity, high throughput, low cost and potential for sub-10 nm resolution. Thanks to these characteristics, the technique has been heavily studied by the semiconductor industry for nanoelectronics, and also applied to alternate fields that might require from the definition of high-density nanoscale features. In this thesis we present a novel fabrication route based on DSA that proves to be suitable for the fabrication of nanomechanical systems. Here, we demonstrate the fabrication of suspended silicon membranes clamped by high-density arrays of silicon nanowires by using a DSA approach based on the graphoepitaxy of polystyrene-b-poly(methyl methacrylate) (PS-b-PMMA), a well-known diblock copolymer. Obtained devices can be further developed for building up high-sensitive mass sensors based on nanomechanical resonators.
Universitat Autònoma de Barcelona. Programa de Doctorat en Enginyeria Electrònica i de Telecomunicació
Jespersen, Michael L. 1979. "Engineering the macro-nano interface: Designing the directed self-assembly and interfacial interactions of gold nanoparticle monolayers." Thesis, University of Oregon, 2008. http://hdl.handle.net/1794/7504.
Повний текст джерелаGold 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
Cruz, Daniel Alejandro. "Hierarchical Self-Assembly and Substitution Rules." Scholar Commons, 2019. https://scholarcommons.usf.edu/etd/7770.
Повний текст джерелаGottlieb, Steven. "High-resolution guiding patterns for the directed self-assembly of block copolymers." Doctoral thesis, Universitat Autònoma de Barcelona, 2018. http://hdl.handle.net/10803/669854.
Повний текст джерелаMolnar, G., L. Dozsa, Z. Vertesy, and Z. J. Horvath. "Thickness Dependent Growth of Epitaxial Iron Silicide Nanoobjects on Si (001)." Thesis, Sumy State University, 2013. http://essuir.sumdu.edu.ua/handle/123456789/35180.
Повний текст джерелаJiang, Feng. "Ligand Controlled Growth of Aqueous II-VI Semiconductor Nanoparticles and Their Self-Assembly." Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/311311.
Повний текст джерелаBouville, Florian. "Self-assembly of anisotropic particles driven by ice growth : Mechanisms, applications and bioinspiration." Thesis, Lyon, INSA, 2013. http://www.theses.fr/2013ISAL0155/document.
Повний текст джерелаSelf-assembly phenomena are of prime interest in materials science, because they fill the gap between assembly of macrostructure and processing of nanomaterials. Self-assembly is based on the spontaneous organization of individual small constituents into patterns and structures. Controlling the spatial arrangement can possibly improve materials properties by maximizing its response in a given direction. Furthermore, particular types of spatial arrangement, such as found in natural structures, can even induce new properties. During the past three years, we have used ice templating process to trigger the assembly of platelet-shaped particles to replicate the hierarchical structure of nacre. Control over this technique allowed structural customization at different length-scales: local orientation of the platelets, ice crystal long range order, and the control if the interfaces between the platelets. This hierarchical process has set the ground for the creation of a new fully mineral nacre-like alumina. The local platelet self-assembly triggered by ice growth was investigated by Discrete Element Modelling which provided new insight into the dynamic phenomenon responsible for the particles alignment. Synchrotron X-ray tomography was used to validated the model results. The different architecture observed in the final samples are not the result of a percolation threshold, as one could expect, but is instead a consequence of the delicate balance between pushing and engulfment at the solidification front. The local alignment of platelets can be beneficial for the functional and structural characteristics of composites and relevant aspects for two potential applications were investigated: the thermal properties of the hexagonal boron nitride/silicon rubber composites and the mechanical properties of macroporous alumina. Further adaptation of the process allowed for long range ordering of the ice crystals (up to the centimeter scale). Different tools have also been developed in order to characterize the response of composites as a function of the architecture at the level of the macropores and particle organisation. Once those two levels of alignment were achieved, the addition of a glassy phase and nanoparticles to the grain boundaries of the platelets introduces, just like in nacre, interfaces capable of deflect and even stopping crack propagation
Hille, Pascal [Verfasser]. "Advanced group III-nitride nanowire heterostructures - self-assembly and position-controlled growth / Pascal Hille." Gießen : Universitätsbibliothek, 2017. http://d-nb.info/1132510511/34.
Повний текст джерелаNardi, Elena. "Growth of organic nanostructures through on-surface reactions : from phthalocyanines self-assembly to polymeric phthalocyanines." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM4351/document.
Повний текст джерелаSurface-assisted covalent coupling of suitably designed molecular precursors on metal surfaces has recently emerged as a new route towards the design of novel molecular architectures promising for future applications. Phthalocyanines and their derivatives have been widely studied for their chemical and optoelectronic properties. In this thesis the synthesis of phthalocyanine compounds is presented. The compounds are obtained through an on-surface reaction between tetracarbonitrile-functionalized precursors and metals. The experimental investigation is carried out by means of scanning tunnelling microscopy and X-Ray photoemission spectroscopy. Two molecular precursors, TCN-DBTTF and PPCN, are studied. TCN-DBTTF molecules are deposited with metal atoms (Mn, Fe, or Cu) on Ag(111) and Au(111). Annealing is used to activate the reaction of cyclotetramerization between precursors and metals. In the most favourable case (TCN-DBTTF with Fe on Ag(111)) the reaction can be activated at 200°C and leads to the synthesis of individual phthalocyanines. Increasing the temperature allows the synthesis of polymeric lines, at 250°C, and small 2D domains, at 275°C. Similar results are obtained for PPCN deposition with Mn or Cu on Au(111). In this latter case, the evolution of core level spectra allows a chemical proof of the on-surface reaction. The factors affecting on-surface cyclotetramerization have also been studied. This study demonstrates the versatility of the method: on-surface cyclotetramerization allows creating original 2D polymers connected by phthalocyanine macrocycles, and may work with a wide range of tetracarbonitrile-functionalized precursors and metallic atoms
Davey, Roger J. "The nucleation and growth of crystals from solution - molecular self assembly, materials science and process technology." Thesis, University of Manchester, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.525976.
Повний текст джерелаDahal, Yuba Raj. "Equilibrium and kinetic factors in protein crystal growth." Diss., Kansas State University, 2017. http://hdl.handle.net/2097/36220.
Повний текст джерелаDepartment of Physics
Jeremy D. Schmit
Diseases such as Alzheimer’s, Parkinson’s, eye lens cataracts, and Type 2 diabetes are the results of protein aggregation. Protein aggregation is also a problem in pharmaceutical industry for designing protein based drugs for long term stability. Disordered states such as precipitates and gels and ordered states such as crystals, micro tubules and capsids are both possible outcomes of protein–protein interaction. To understand the outcomes of protein–protein interaction and to find the ways to control forces, it is required to study both kinetic and equilibrium factors in protein–protein interactions. Salting in/salting out and Hofmeister effects are familiar terminologies used in protein science field from more than a century to represent the effects of salt on protein solubility, but they are yet to be understood theoretically. Here, we build a theory accounting both attractive and repulsive electrostatic interactions via the Poisson Boltzmann equation, ion–protein binding via grand cannonical partition function and implicit ion–water interaction using hydrated ion size, for describing salting in/salting out phenomena and Hofmeister and/or salt specific effect. Our model free energy includes Coulomb energy, salt entropy and ion–protein binding free energy. We find that the salting in behavior seen at low salt concentration near the isoelectric point of the protein is the output of Coulomb energy such that the addition of salt not only screens dipole attraction but also it enhances the monopole repulsion due to anion binding. The salting out behavior appearing after salting in at high salt concentration is due to a salt mediated depletion interaction. We also find that the salting out seen far from the isoelectric point of the protein is dominated by the salt entropy term. At low salt, the dominant effect comes from the entropic cost of confining ions within the aggregates and at high salt, the dominant effect comes from the entropy gain by ions in solution by enhancing the depletion attraction. The ion size has significant effects on the entropic term which leads to the salt specificity in the protein solubility. Crystal growth of anisotropic and fragile molecules such as proteins is a challenging task because kinetics search for a molecule having the correct binding state from a large ensemble of molecules. In the search process, crystal growth might suffer from a kinetic trap called self–poisoning. Here, we use Monte Carlo simulation to show why protein crystallization is vulnerable to the poisoning and how one can avoid such trap or recover crystal growth from such trap during crystallization. We show that self–poisoning requires only three minimal ingredients and these are related to the binding affinity of a protein molecule and its probability of occurrence. If a molecule attaches to the crystal in the crystallographic state then its binding energy will be high but in protein system this happens with very low probability (≈ 10−5). On the other hand, non–crystallographic binding is energetically weak, but it is highly probable to happen. If these things are realized, then it will not be surprising to encounter with self–poisoning during protein crystallization. The only way to recover or avoid poisoning is to alter the solution condition slightly such as by changing temperature or salt concentration or protein concentration etc.
Yoshikawa, Taro [Verfasser], and Oliver [Akademischer Betreuer] Ambacher. "Toward ultra-thin nanocrystalline diamond film growth: electrostatic self-assembly of non-aggregated diamond nanoparticles onto substrate surfaces." Freiburg : Universität, 2017. http://d-nb.info/115294469X/34.
Повний текст джерелаChen, Jing. "Novel H-bond donor polymers for layer-by-layer self-assembly multilayered films." Thesis, Lyon, INSA, 2013. http://www.theses.fr/2013ISAL0087/document.
Повний текст джерелаThis work deals with the design of novel hydrogen-bond donor polymers and their use as partner in new tailor-made multilayered films prepared by the layer-by-layer (LbL) process. In this context, a novel regioselective and chemoselective “click-type” reaction of unprotected mercaptoalcohols onto poly(2,3,4,5,6-pentafluoro-styrene) (PPFS) has been developed, and applied to the synthesis of new hydroxylated H-bond donor polymers. This coupling with heterofunctional thiol is used to prepare a library of polymers differing in the degree of substitution (DS) and/or functionality. The fine control of these parameters makes it possible to tune their interaction ability with various acceptor polymers such as poly(4-vinyl pyridine) (P4VP), poly(n-butyl acrylate) (PBA) and poly(ethylene oxide) (PEO), such that all possible scenarios (immiscible blend, partially or totally miscible blend or interpolymer complex) can be achieved. Subsequently, the resulting H-bond donor polymers (PPFS derivatives) were used to successfully build-up multilayered films with using P4VP as partner via layer-by-layer (LbL) through the dip deposition process. The influence of various parameters related to structure of the partners (DS, nature of the PPFS derivatives), the chemical structure of the surface onto which the film is built-up (self-assembled monolayer vs. polymer brush) and the deposition process (concentration of deposition solutions, nature of the first deposited partner) was in-depth evaluated, on both the growth mechanism and on the surface features of the multilayered films
Mukherjee, Sanjoy. "Synthesis, Characterization, and Growth Mechanism of Single-Walled Metal Oxide Nanotubes." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/16176.
Повний текст джерелаKleppmann, Nicola [Verfasser], Sabine [Akademischer Betreuer] Klapp, and Andreas [Akademischer Betreuer] Heuer. "Simulation of growth and self-assembly of complex molecules on surfaces / Nicola Kleppmann. Gutachter: Andreas Heuer ; Sabine Klapp. Betreuer: Sabine Klapp." Berlin : Technische Universität Berlin, 2015. http://d-nb.info/1077040156/34.
Повний текст джерелаJones, Aleksy K. "Kinetically determined surface morphology in epitaxial growth." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/2499.
Повний текст джерелаJohnson, Tamina L. "Elastin-Like Polypeptide Fusion Tag as a Protein-Dependent Solubility Enhancer of Cysteine-Knot Growth Factors." Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7629.
Повний текст джерелаDaher, Mansour Michel. "Transition metal nanolines on a nanopatterned silver substrate : self-organized growth and magnetic properties." Thesis, Aix-Marseille, 2019. http://www.theses.fr/2019AIXM0287.
Повний текст джерелаInterest in the magnetic properties of low dimensional transition metal and lanthanide nanostructures has seen an unprecedented rise in the last two decades due to both their fundamental interest and perspectives of technological applications. Remarkably, the magnetic properties of nanostructures can be tuned by controlling their geometry, atomic structure and chemical environments. In this thesis, a one-dimensional template composed of self-organized Si nanoribbons is used to grow transition metal nanolines, prior to the characterization of their magnetic properties. The geometries and the atomic structure of both the Si nanoribbons and the metal nanolines were investigated in situ by scanning tunneling microscopy. The growth mechanisms were investigated by exploring a large set of growth conditions. Regarding the Si growth, our study shows that a temperature of 490 K is necessary to obtain a long-range ordered one-dimensional template. Concerning the transition metal study, the results resolved the nanoline geometries and atomic structures.To access the magnetic properties of the Co nanolines on Si, XMCD measurements were performed using different magnetic field orientations and temperatures.The results show that the first two Co layers directly adsorbed onto the Si nanoribbons present a weak magnetic response while the upper Co layers exhibit an enhanced magnetization. Remarkably, two in-plane easy axes of magnetization were evidenced.The magnetic moments and the magnetic anisotropic energy are determined quantitatively.Temperature-dependent investigations strongly suggest a superparamagnetic behavior
Carnevale, Santino D. "Catalyst-free III-nitride Nanowires by Plasma-assisted Molecular Beam Epitaxy: Growth, Characterization, and Applications." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1374066626.
Повний текст джерелаHaubold, Danny, Annett Reichhelm, Alexander Weiz, Lars Borchardt, Christoph Ziegler, Lydia Bahrig, Stefan Kaskel, Michael Ruck, and Alexander Eychmüller. "The Formation and Morphology of Nanoparticle Supracrystals." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-209752.
Повний текст джерелаBaltazar, Jose A. "Polycyclic aromatic hydrocarbons: exploring new processes and materials for electronics." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/51787.
Повний текст джерелаAl-Brasi, Enteisar. "The growth and characterization of films of noble metal nanocrystals and inorganic semiconductors at the interface of two immiscible liquids." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/the-growth-and-characterization-of-films-of-noble-metal-nanocrystals-and-inorganic-semiconductors-at-the-interface-of-two-immiscible-liquids(5652496a-6e6d-4e91-a21b-6ae1b3f36a87).html.
Повний текст джерелаTeng, Die. "Computational studies of transition metal nanoclusters on metal-supported graphene moiré." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/51830.
Повний текст джерелаPithan, Linus. "On the role of external stimuli to tailor growth of organic thin films." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät, 2017. http://dx.doi.org/10.18452/17749.
Повний текст джерелаThe research performed in the framework of this thesis focuses on new strategies to effectively control the growth of crystalline thin films of functional organic molecules and attributes the quest for additional growth control parameters in organic molecular beam deposition (OMBD). First the influence of light on the growth process of the sexithiophene (6T) is studied. We find that 6T thin films deposited as conventional in dark environments on KCl exhibit a bimodal growth with phase coexistence of two crystal polymorphs. In contrast, films grown under illumination with 532 nm light show increased phase purity. Further, we establish light-directed molecular self-assembly (LDSA) to generate permanently aligned thin films of tetracene (C18H12) and demonstrate direct patterning with light. Polarized light illumination leads to azimuthally photoaligned films on isotropic, amorphous substrates. Thus, LDSA can be regarded as a new degree of freedom in the quest for control-parameters in organic thin film growth. Next the impact of dynamic temperature oscillations on the time scales of molecular monolayer growth during organic molecular beam deposition is discussed. We strongly increase the island density during nucleation and selectively increase interlayer diffusion at later stages of monolayer growth. We analyse the interplay between molecular interlayer transport and island sizes to understand kinetic processes during growth. In a fourth experiment we show how thermal annealing can be used to improve smoothness and to increase the lateral size of crystalline islands of n-alkane (TTC, C44H90) films. We employ real-time optical phase contrast microscopy to track the diffusion across monomolecular step edges which causes the unusual smoothing during annealing. We rationalise the smoothing behaviour with the highly anisotropic attachment energies and low surface energies of TTC.
Zschintzsch-Dias, Manuel. "Self organized formation of Ge nanocrystals in multilayers." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-86838.
Повний текст джерелаOurdjini, Oualid. "Etude par microscopie à effet tunnel de la croissance de polymères 2D sur des surfaces métalliques." Thesis, Aix-Marseille, 2012. http://www.theses.fr/2012AIXM4315/document.
Повний текст джерелаThe growth of two dimensional polymers has been studied under ultra-high vacuum on metallic surfaces by scanning tunnelling microscopy (STM). The first study relates on the growth of two dimensional covalent nanoporous networks obtained after dehydratation reaction of the 1,4 diboronic acid benzene molecule (BDBA). The best networks have been obtained with high molecular flux on silver metallic substrates maintained at 150°C during deposition. The second study relates on chemical reaction between the 1, 2, 4, 5 tetracyanobenzene molecule (TCNB) and iron atoms. The reaction takes place after an annealing at 200°C. In that case some iron octacyanophthalocyanine have been successfully synthesised at surfaces. This work opens new perspectives for the fabrication of 2D original materials by chemical reactions on surfaces
Diebold, Morgane. "Systèmes composites organogélateurs/polymères semi-conducteurs : de la preuve conceptuelle aux matériaux nanostructurés pour l'électronique plastique." Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAE002.
Повний текст джерелаImproving the performances of organic photovoltaic devices requires morphology control of the active layers. Highly nanostructured donor-acceptor bulk heterojunctions were prepared by heterogeneous nucleation of poly (3-hexylthiophene) (P3HT, donor) on naphthalene diimide organogelators fibers (NDI, acceptor). The first part of this work was dedicated to the self-assembly of NDI-core organogelators substituted by amide groups and trialkoxyphenyls dendrons. We evaluated the influence of the flexible chain between the naphthalene core and the amide groups (2 C-C bonds for NDI2 and 4 for NDI4) on the physico-chemical properties of the organogelators.The second part of this work focused on the polymorphism of NDI2 with identification of four different polymorphs with their optical, spectroscopic and structural signatures. A phase diagram of NDI2 in the solid state was determined. The last part of this manuscript concerns the fabrication of donor-acceptor nano-composites between NDI organogelators and P3HT. The formation process in solution of these nano-composites was analyzed by following the crystallization kinetics of P3HT by UV-Vis absorption spectroscopy and the thin film morphology (shish-kebab structures) by transmission electron microscopy. The nucleating effect of various organogelators on P3HT was demonstrated. Solar cells were made from the composites P3HT:PCBM : organogelator and their energetic conversion yield was shown to be increased in the presence of organogelators
Varghai, Daniel. "Tubular Tissue Engineered Scaffold-Free High-Cell-Density Mesenchymal Condensations For Femoral Defect Regeneration." Case Western Reserve University School of Graduate Studies / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=case1497222797338966.
Повний текст джерелаDe, Vet Christiaan J. F. "Auto-assemblage d'un anthacène fluorescent aux échelles nano- et micrométriques par photoréaction contrôlée." Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0333/document.
Повний текст джерелаThe spatial and temporal control of the self-assembly of fluorescent molecules into organized nano-objects and into soft materials was achieved by photochemistry. The quantitative photodecarbonylation of the progelator dkDDOA under irradiation generates the supergelator 2,3-didecyloxyanthracene (DDOA) at room temperature and simultaneously gelates DMSO. dkDDOA is reactive under excitation withblue light due to the light sensitive alpha-diketone moiety that is added to the aromatic core.Additional colour-tuning from blue to green emission from the gel was achieved by adding a similar photoreactive 1,2-diketone-5,12-diphenyltetracene that yields a green emissive 5,12-diphenyltetracene sensitized through an efficient energy transfer. Under a microscope, focused laser irradiation enables the patterning of blue-emissive nanofibers on to a glass surface. Although the surface is non-treated, micropatterns of highly aligned DDOA nanofibers can be obtained. These surfaces emit linearly polarized blue light,as proven with polarization microscopy. The high anisotropy and the orientation of the fibers was achieved by controlling the nucleation density and the direction of scanning of the focused laser. Perpendicularly oriented micropatterns can thereby be juxtaposed on the same surface
Chomette, Cyril. "Design et fabrication de meta-atomes plasmoniques à partir de nanoparticules à patchs." Thesis, Bordeaux, 2015. http://www.theses.fr/2015BORD0232/document.
Повний текст джерелаMetamaterials are a novel class of artificial composite materials, typically made of subunit called meta-atoms and exhibiting unusual properties. Such meta-atoms, have to be architecturedat the nanometric level, to induce as extraordinary properties as a negative refractive index. In thiscontext, we developed patchy particles, capable to create interactions along predetermined directions.Multipodic clusters made of those (dielectric) particles surrounded by a controlled number ofplasmonic satellites (gold) were developed. We focused on isotropic clusters deriving fromtetrahedral, octahedral and icosahedral geometry (three of the fifth Platonic solids). For that purpose,we used silica/polystyrene clusters, obtained from seeded emulsion polymerization, as template. Byderiving those clusters, patchy particles bearing dimples containing grafted residual polystyrene chainswere obtained. By chemically deriving those chains, we explored two synthetic pathways, thedecoration of the dimples with gold colloids subsequently grown or the anchoring of silica satellitesonto which gold shells were subsequently grown. The second one was prove to offer a better controlover the cluster morphology as well as the inter-satellites gap (few nanometer) which is pivotal toensure an optimal plasmonic coupling. Then, the optical properties of the as obtained clusters weresimulated and measured
Jubert, Pierre-Olivier. "Croissance et propriétés magnétiques de nanostructures épitaxiées auto-assemblées : le système Fe/Mo(110)." Phd thesis, Université Joseph Fourier (Grenoble), 2001. http://tel.archives-ouvertes.fr/tel-00004054.
Повний текст джерелаXiao, Qijun. "Hierarchical multiple bit clusters and patterned media enabled by novel nanofabrication techniques – High resolution electron beam lithography and block polymer self assembly." 2010. https://scholarworks.umass.edu/dissertations/AAI3397756.
Повний текст джерелаWei-CheTang and 唐偉哲. "Catalyst-assisted Growth of InGaN Nanowires and Chlorine-assisted Growth of Self-assembly GaN Nanorods for Optoelectronic Device." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/07931298472155093208.
Повний текст джерела國立成功大學
化學工程學系
104
This research is involving of two parts. First part is that Au-assisted growths of InGaN nanowires by VLS growth mechanism at 700℃. GaN nanowires with a mount of planar defects were synthesized as low indium vapor pressure in the gas phase. As the high indium vapor pressure in the gas phase, there are InGaN nanowires with 14% atomic indium and high-intensity wavelength emission at 410 nm grown on Si(100). According to Le Chatelier's Principle, in order to enhance the thermal stability of InN material at the high temperature, the high nitrogen plasma concentration has used. Therefore, the indium content in InGaN nanowires with 460 nm emission light increases to 24% atomic. Other part is the single crystal GaN nanorods grown for Optoelectronic devices. In advance, at 960℃ growth temperature, high-quality Si-doped n-GaN nanorods were synthesized. Cl2-assisted InGaN and p-GaN epitaxial films were respectively grown on n-GaN nanorods at 600℃ to form p-i-n GaN for Optoelectronic structure.
Qian, Jieshu. "Factors Affecting the Growth and Fragmentation of Polyferrocenylsilane Diblock Copolymer Micelles." Thesis, 2013. http://hdl.handle.net/1807/65522.
Повний текст джерелаChung, Siyon. "Microfluidic Modeling of Cell Flow & Self-assembly of Gold Nanorods with Different Lengths." Thesis, 2012. http://hdl.handle.net/1807/35514.
Повний текст джерелаSwain, Monalisa. "Study Of Structure, Dynamics & Self-Assembly Of Human Insulin-Like Growth Factor Binding Protein-2 By Novel NMR And Biophysical Methods." Thesis, 2011. http://etd.iisc.ernet.in/handle/2005/2357.
Повний текст джерелаThirupathi, Ravula. "Design, Synthesis and Characterization of Novel Nanomaterials." Thesis, 2014. http://hdl.handle.net/2005/3177.
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