Tesis: "Nano-Ion"

1

Toyoda, Noriaki. "Nano-Processing with Gas Cluster Ion Beams". Kyoto University, 1999. http://hdl.handle.net/2433/8951.

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学位授与年月日: 1999-03-23 ; 学位の種類: 新制・課程博士 ; 学位記番号: 1823
In this thesis, fundamental properties of gas cluster ion beams and their non-linear irradiation effects are studied. Applications in the fabrication of nano-structures (nano-processes) are demonstrated, as based on knowledge of the interactions between clusters and solid surfaces. In chapter 2, a cluster source which provides an intense neutral cluster beam by supersonic expansion from a Laval nozzle is described, and the high current cluster ion beam equipment is explained. By optimization of both ionization and transport conditions of the cluster beam, a high cluster ion current density of a few μA/cm2 was achieved. The detailed cluster size distribution following a supersonic expansion and the characteristics of the cluster beams are discussed in chapter 3 based on data obtained with a high resolution time of flight mass spectrometer. The formation of inert, reactive and complex gas clusters was verified, and their average cluster size was 2000atoms/cluster. With increasing cluster size, the ionization and collision cross-section increased, however, the kinetic energy of the impact was compensated by the cohesive energy of a large cluster. In chapter 4, interactions of cluster and target atoms in an energetic cluster ion impact are discussed. Most of the kinetic energy of cluster ions was deposited with high density on the surface regions of the targets, and subsequently, multiple collisions between targets and clusters occurred. This dense energy deposition resulted in intrinsic non-linear sputtering effects, such as high yield sputtering and crater formation, which could not be explained by the summation of the irradiation effects induced by the same number of monomer ions. The lateral sputtering effect, which is explained in that many sputtered atoms with cluster ions are emitted in the horizontal direction on the surface plane, was clarified experimentally for the first time, and this was verified by STM observations of single traces of cluster ion impacts. In chapter 5, an enhancement of the sputtering effects with reactive cluster ion beams and their applications are discussed. Since the impact area of the target by a cluster ion occurred under high temperature and high pressure conditions, chemical reactions on the target surface were enhanced. In the case of reactive cluster ion irradiation, dissociation of reactive molecules and clusters occurred simultaneously, and subsequently, enhancement of the etching rate was observed as a consequence of the production of volatile materials. Reactive cluster ion etching could be applied for Si fine pattern etching, and it provided solutions for charging up, isotropic etching, microloading and radiation damage problems. In chapter 6, the surface smoothing effect and mechanisms with cluster ions are discussed. The cluster ion exhibited marked surface smoothing effects and it was made clear from both experimental and simulation results that the lateral sputtering effect was significant for surface smoothing. Very smooth surfaces of CVD diamond films and SiC single crystal substrates were obtained using the gas cluster ion beam processing; these materials are difficult to etch using conventional processes. From these results, it can be summarized that gas cluster ion beam processing is effective in the fabrication of nano-structures and applications in the industrial field are expected.
Kyoto University (京都大学)
0048
新制・課程博士
博士(工学)
甲第7843号
工博第1823号
新制||工||1140(附属図書館)
UT51-99-G437
京都大学大学院工学研究科電子物性工学専攻
(主査)教授山田公, 教授橘邦英, 教授今西信嗣
学位規則第4条第1項該当

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2

Jung, Daniel. "Ion acceleration from relativistic laser nano-target interaction". Diss., lmu, 2012. http://nbn-resolving.de/urn:nbn:de:bvb:19-140744.

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3

Hohenschutz, Max. "Nano-ions in interaction with non-ionic surfactant self-assemblies". Thesis, Montpellier, 2020. http://www.theses.fr/2020MONTS064.

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Les ions de taille nanométrique (nano-ions), tels que les clusters ioniques de bore, les polyoxométalates (POM) et les grands ions organiques, ont suscité un intérêt remarquable ces dernières années en raison de leur capacité à s’adsorber ou se lier à des systèmes chimiques électriquement neutres, tels que les molécules hôtes macrocycliques, les nanoparticules, les tensioactifs et les polymères, etc. Il a été démontré que ces processus d'adsorption ou de liaison sont induits par un phénomène médié par solvant, l'effet chaotropique, qui pousse le nano-ion de la masse d'eau vers une interface. Ainsi, l'eau d'hydratation de l'ion et de l'interface est libérée dans la masse d'eau, ce qui entraîne une restitution de la structure intrinsèque de l'eau. Cet effet est particulièrement fort pour les nano-ions. Ils sont par conséquent appelés ions superchaotropiques ou hydrophobes dans le prolongement des ions classiques (faiblement) chaotropiques tels que le SCN-. Tous les superchaotropes couramment étudiés, bien que chimiquement divers, partagent des caractéristiques physiques telles qu'une faible densité de charge et une grande polarisabilité. Les effets des nano-ions sur les auto-assemblages de tensioactifs non ioniques éthoxylés, les phases micellaires et bicouches, sont ici élucidés pour tirer des conclusions sur leur nature chaotropique et/ou hydrophobe. En combinant la diffusion aux petits angles des neutrons et des rayons X (SANS et SAXS), et les diagrammes de phase, les systèmes tensioactifs non ioniques/nano-ion sont examinés et comparés, du nanomètre à l'échelle macroscopique. Ainsi, il est montré que tous les nano-ions étudiés induisent un chargement électrique des assemblages de tensioactifs ainsi qu'une déshydratation des têtes de tensioactif non-ionique. En outre, les ions chaotropiques ou hydrophobes diffèrent dans leurs effets sur la forme micellaire. Les ions chaotropiques entraînent les micelles allongées de tensioactif non-ionique vers les micelles sphériques (augmentation de la courbure), tandis que les ions hydrophobes provoquent une transition vers les phases bicouches (diminution de la courbure). Il est conclu que les nano-ions superchaotropiques agissent comme des tensioactifs ioniques car leur ajout à des systèmes de tensioactifs non ioniques provoque un effet de charge. Cependant, les nano-ions et les tensioactifs ioniques sont fondamentalement différents par leur association avec l'ensemble des tensioactifs non ioniques. Le nano-ion s'adsorbe sur les têtes des tensioactifs non ioniques par effet chaotropique, tandis que le tensioactif ionique s'ancre dans les micelles entre les queues des tensioactifs non ioniques par effet hydrophobe. La comparaison des effets de l'ajout de nano-ions ou de tensioactifs ioniques à des tensioactifs non ioniques a été approfondie sur les mousses. Les mousses ont été étudiées en ce qui concerne l'épaisseur du film de mousse, le drainage dans le temps et la stabilité, respectivement en utilisant la SANS, l'analyse d'image et la conductométrie. Le POM superchaotropique testé (SiW12O404-, SiW) ne mousse pas dans l'eau contrairement au SDS classique de tensioactif ionique. Néanmoins, l'ajout de petites quantités de SiW ou de SDS à une solution moussante de tensioactif non ionique a permis d'obtenir des mousses plus humides avec une durée de vie plus longue. Entre-temps, l'épaisseur du film de mousse (déterminée en SANS) est augmentée en raison de la charge électrique des monocouches de tensioactifs non ioniques dans le film de mousse. Il est conclu que le comportement remarquable des nano-ions - ici sur les systèmes tensioactifs non ioniques - peut être étendu aux systèmes colloïdaux, tels que les mousses, les polymères, les protéines ou les nanoparticules. Cette thèse démontre que le comportement superchaotropique des nano-ions est un outil polyvalent qui peut être utilisé dans de nouvelles formulations de matériaux et d'applications de la matière molle
Nanometer-sized ions (nano-ions), such as ionic boron clusters, polyoxometalates (POMs) and large organic ions, have spawned remarkable interest in recent years due to their ability to adsorb or bind to electrically neutral chemical systems, such as macrocyclic host molecules, colloidal nano-particles, surfactants and polymers etc. The underlying adsorption or binding processes were shown to be driven by a solvent-mediated phenomenon, the chaotropic effect, which drives the nano-ion from the water bulk towards an interface. Thus, hydration water of the ion and the interface is released into the bulk resulting in a bulk water structure recovery. This effect is particularly strong for nano-ions. Therefore, they were termed superchaotropic or hydrophobic ions as an extension to classical (weakly) chaotropic ions such as SCN-. All commonly studied superchaotropes, though chemically diverse, share physical characteristics such as low charge density and high polarizability. Herein, the effects of nano-ions on ethoxylated non-ionic surfactant self-assemblies, micellar and bilayer phases, are elucidated to draw conclusions on their chaotropic and/or hydrophobic nature. By combining small angle scattering of neutrons and x-rays (SANS and SAXS), and phase diagrams, non-ionic surfactant/nano-ion systems are examined and compared, from the nanometer to the macroscopic scale. Thus, all studied nano-ions are found to induce a charging of the surfactant assemblies along with a dehydration of the non-ionic surfactant head groups. Furthermore, chaotropic and hydrophobic ions differ in their effects on the micellar shape. Superchaotropic ions drive the elongated non-ionic surfactant micelles towards spherical micelles (increase in curvature), whereas hydrophobic ions cause a transition towards bilayer phases (decrease in curvature). It is concluded that superchaotropic nano-ions act like ionic surfactants because their addition to non-ionic surfactant systems causes a charging effect. However, nano-ions and ionic surfactants are fundamentally different by their association with the non-ionic surfactant assembly. The nano-ion adsorbs to the non-ionic surfactant heads by the chaotropic effect, while the ionic surfactant anchors into the micelles between the non-ionic surfactant tails by the hydrophobic effect. The comparison of the effects of adding nano-ions or ionic surfactant to non-ionic surfactant was further investigated on foams. The foams were investigated regarding foam film thickness, drainage over time and stability, respectively using SANS, image analysis and conductometry. The tested superchaotropic POM (SiW12O404-, SiW) does not foam in water in contrast to the classical ionic surfactant SDS. Nevertheless, addition of small amounts of SiW or SDS to a non-ionic surfactant foaming solution resulted in wetter foams with longer lifetimes. Meanwhile, the foam film thickness (determined in SANS) is increased due to the electric charging of the non-ionic surfactant monolayers in the foam film. It is concluded that the remarkable behavior of nano-ions – herein on non-ionic surfactant systems – can be extended to colloidal systems, such as foams, polymers, proteins or nanoparticles. This thesis demonstrates that the superchaotropic behavior of nano-ions is a versatile tool to be used in novel formulations of soft matter materials and applications

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4

Castro, Olivier de. "Development of a Versatile High-Brightness Electron Impact Ion Source for Nano-Machining, Nano-Imaging and Nano-Analysis". Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS468/document.

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Les nano-applications utilisant des faisceaux d'ions focalisés nécessitent des sources d'ions à haute brillance avec une faible dispersion en énergie (ΔE) ce qui permet une excellente résolution latérale et un courant d'ions suffisamment élevé pour induire des vitesses d'érosion raisonnables et des rendements élevés d'émission électronique et ionique. Les objectifs de cette thèse sont le développement d'une source d'ions basée sur l'impact électronique ayant une brillance réduite Br de 10³ – 10⁴ A m⁻² sr ⁻ ¹ V⁻ ¹, une dispersion en énergie ΔE ≲ 1 eV et un choix polyvalent d'ions. Le premier concept évalué consiste à focaliser un faisceau d'électrons à une énergie de 1 keV entre deux électrodes parallèles distant de moins d'un millimètre. Le volume d'ionisation « micrométrique » est formé au-dessus d'une ouverture d'extraction de quelques dizaines de µm. En utilisant un émetteur d'électrons LaB₆ et une pression de 0.1 mbar dans la région d'ionisation, Br est proche de 2.10² A m⁻² sr ⁻ ¹ V ⁻ ¹ avec des tailles de source de quelques µm, des courants de quelques nA pour Ar⁺/Xe⁺/O₂ ⁺ et une dispersion en énergie ΔE < 0.5 eV. La brillance réduite Br est encore en dessous de la valeur minimum de notre objectif et la pression de fonctionnement très faible nécessaire pour l'émetteur LaB₆ ne peut être obtenue avec une colonne d'électrons compacte, donc ce prototype n'a pas été construit.Le deuxième concept de source d'ions évalué est basé sur l’idée d’obtenir un faisceau ionique à fort courant avec une taille de source et un demi-angle d’ouverture similaire aux résultats du premier concept de source, mais en changeant l’interaction électron-gaz et la collection des ions. Des études théoriques et expérimentales sont utilisées pour l’évaluation de la performance de ce deuxième concept et de son utilité pour les nano-applications basées sur des faisceaux d'ions focalisés
High brightness low energy spread (ΔE) ion sources are needed for focused ion beam nano-applications in order to get a high lateral resolution while having sufficiently high ion beam currents to obtain reasonable erosion rates and large secondary electron/ion yields. The objectives of this thesis are: the design of an electron impact ion source, a reduced brightness Br of 10³ – 10⁴ A m⁻² sr⁻ ¹ V⁻ ¹ with an energy distribution spread ΔE ≲ 1 eV and a versatile ion species choice. In a first evaluated concept an electron beam is focussed in between two parallel plates spaced by ≲1 mm. A micron sized ionisation volume is created above an extraction aperture of a few tens of µm. By using a LaB₆ electron emitter and the ionisation region with a pressure around 0.1 mbar, Br is close to 2.10² A m⁻² sr ⁻ ¹ V ⁻ ¹ with source sizes of a few µm, ionic currents of a few nA for Ar⁺/Xe⁺/O₂ ⁺ and the energy spread being ΔE < 0.5 eV. The determined Br value is still below the minimum targeted value and furthermore the main difficulty is that the needed operation pressure for the LaB₆ emitter cannot be achieved across the compact electron column and therefore a prototype has not been constructed. The second evaluated source concept is based on the idea to obtain a high current ion beam having a source size and half-opening beam angle similar to the first concept, but changing the electron gas interaction and the ion collection. Theoretical and experimental studies are used to evaluate the performance of this second source concept and its usefulness for focused ion beam nano-applications

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5

Perre, Emilie. "Nano-structured 3D Electrodes for Li-ion Micro-batteries". Doctoral thesis, Uppsala universitet, Institutionen för materialkemi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-119485.

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A new challenging application for Li-ion battery has arisen from the rapid development of micro-electronics. Powering Micro-ElectroMechanical Systems (MEMS) such as autonomous smart-dust nodes using conventional Li-ion batteries is not possible. It is not only new batteries based on new materials but there is also a need of modifying the actual battery design. In this context, the conception of 3D nano-architectured Li-ion batteries is explored. There are several micro-battery concepts that are studied; however in this thesis, the focus is concentrated on one particular architecture that can be described as the successive deposition of battery components (active material, electrolyte, active material) on free-standing arrays of nano-sized columns of a current collector. After a brief introduction about Li-ion batteries and 3D micro-batteries, the electrodeposition of Al through an alumina template using an ionic liquid electrolyte to form free-standing columns of Al current collector is described. The crucial deposition parameters influencing the nucleation and growth of the Al nano-rods are discussed. The deposition of active electrode material on the nano-structured current collector columns is described for 2 distinct active materials deposited using different techniques. Deposition of TiO2 using Atomic Layer Deposition (ALD) as active material on top of the nano-structured Al is also presented. The obtained deposits present high uniformity and high covering of the specific surface of the current collector. When cycled versus lithium and compared to planar electrodes, an increase of the capacity was proven to be directly proportional to the specific area gained from shifting from a 2D to a 3D construction. Cu2Sb 3D electrodes were prepared by the electrodeposition of Sb onto a nano-structured Cu current collector followed by an annealing step forcing the alloying between the current collector and Sb. The volume expansion observed during Sb alloying with Li is buffered by the Cu matrix and thus the electrode stability is greatly enhanced (from only 20 cycles to more than 120 cycles). Finally, the deposition of a hybrid polymer electrolyte onto the developed 3D electrodes is presented. Even though the deposition is not conformal and that issues of capacity fading need to be addressed, preliminary results attest that it is possible to cycle the obtained 3D electrode-electrolyte versus lithium without the appearance of short-circuits.

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6

Evanoff, Kara. "Highly structured nano-composite anodes for secondary lithium ion batteries". Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/53388.

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Interest in high performance portable energy devices for electronics and electric vehicles is the basis for a significant level of activity in battery research in recent history. Li-ion batteries are of particular interest due to their high energy density, decreasing cost, and adaptable form factor. A common goal of researchers is to develop new materials that will lower the cost and weight of Li-ion batteries while simultaneously improving the performance. There are several approaches to facilitate improved battery system-level performance including, but not limited to, the development of new material structures and/or chemistries, manufacturing techniques, and cell management. The performed research sought to enhance the understanding of structure-property relationships of carbon-containing composite anode materials in a Li-ion cell through extensive materials and anode performance characterization. The approach was to focus on the development of new electrode material designs to yield higher energy and power characteristics, as well as increased thermal and electrical conductivities or mechanical strength, using techniques that could be scaled for large volume manufacturing. Here, three different electrode architectures of nanomaterial composites were synthesized and characterized. Each electrode structure consisted of a carbon substrate that was conformally coated with a high Li capacity material. The dimensionality and design for each structure was unique, with each offering different advantages. The addition of an external coating to further increase the stability of high capacity materials was also investigated.

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7

Roshchupkina, Olga. "Ion beam induced structural modifications in nano-crystalline permalloy thin films". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-114158.

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In the last years, there is a rise of interest in investigation and fabrication of nanometer sized magnetic structures due to their various applications (e.g. for data storage or micro sensors). Over the last several decades ion beam implantation became an important tool for the modification of materials and in particular for the manipulation of magnetic properties. Nanopatterning and implantation can be done simultaneously using focused-ion beam (FIB) techniques. FIB implantation and standard ion implantation differ in their beam current densities by 7 orders of magnitude. This difference can strongly influence the structural and magnetic properties, e.g. due to a rise of the local temperature in the sample during ion implantation. In previous investigations both types of implantation techniques were studied separately. The aim of the current research was to compare both implantation techniques in terms of structural changes and changes in magnetic properties using the same material system. Moreover, to separate any possible annealing effects from implantation ones, the influence of temperature on the structural and magnetic properties were additionally investigated. For the current study a model material system which is widely used for industrial applications was chosen: a 50 nm thick non-ordered nano-crystalline permalloy (Ni81Fe19) film grown on a SiO2 buffer layer based onto a (100)-oriented Si substrate. The permalloy films were implanted with a 30 keV Ga+ ion beam; and also a series of as-deposited permalloy films were annealed in an ultra-high vacuum (UHV) chamber. Several investigation techniques were applied to study the film structure and composition, and were mostly based on non-destructive X-ray investigation techniques, which are the primary focus of this work. Besides X-ray diffraction (XRD), providing the long-range order crystal structural information, extended X-ray absorption fine structure (EXAFS) measurements to probe the local structure were performed. Moreover, the film thickness, surface roughness, and interface roughness were obtained from the X-ray reflectivity (XRR) measurements. Additionally cross-sectional transmission electron microscope (XTEM) imaging was used for local structural characterizations. The Ga depth distribution of the samples implanted with a standard ion implanter was measured by the use of Auger electron spectroscopy (AES) and Rutherford backscattering (RBS), and was compared with theoretical TRIDYN calculation. The magnetic properties were characterized via polar magneto-optic Kerr effect (MOKE) measurements at room temperature. It was shown that both implantation techniques lead to a further material crystallization of the partially amorphous permalloy material (i.e. to an increase of the amount of the crystalline material), to a crystallite growth and to a material texturing towards the (111) direction. For low ion fluences a strong increase of the amount of the crystalline material was observed, while for high ion fluences this rise is much weaker. At low ion fluences XTEM images show small isolated crystallites, while for high ones the crystallites start to grow through the entire film. The EXAFS analysis shows that both Ni and Ga atom surroundings have a perfect near-order coordination corresponding to an fcc symmetry. The lattice parameter for both implantation techniques increases with increasing ion fluence according to the same linear law. The lattice parameters obtained from the EXAFS measurements for both implantation types are in a good agreement with the results obtained from the XRD measurements. Grazing incidence XRD (GIXRD) measurements of the samples implanted with a standard ion implanter show an increasing value of microstrain with increasing ion fluence (i.e. the lattice parameter variation is increasing with fluence). Both types of implantation result in an increase of the surface and the interface roughness and demonstrate a decrease of the saturation polarization with increasing ion fluence. From the obtained results it follows that FIB and standard ion implantation influence structure and magnetic properties in a similar way: both lead to a material crystallization, crystallite growth, texturing and decrease of the saturation polarization with increasing ion fluence. A further crystallization of the highly defective nano-crystalline material can be simply understood as a result of exchange processes induced by the energy transferred to the system during the ion implantation. The decrease of the saturation polarization of the implanted samples is mainly attributed to the simple presence of the Ga atoms on the lattice sites of the permalloy film itself. For the annealed samples more complex results were found. The corresponding results can be separated into two temperature regimes: into low (≤400°C) and high (>400°C) temperatures. Similar to the implanted samples, annealing results in a material crystallization with large crystallites growing through the entire film and in a material texturing towards the (111) direction. The EXAFS analysis shows a perfect near-order coordination corresponding to an fcc symmetry. The lattice parameter of the annealed samples slightly decreases at low annealing temperatures, reaches its minimum at about ~400°C and slightly rises at higher ones. From the GIXRD measurements it can be observed that the permalloy material at temperatures above >400°C reaches its strain-free state. On the other hand, the film roughness increases with increasing annealing temperature and a de-wetting of the film is observed at high annealing temperatures. Regardless of the material crystallization and texturing, the samples annealed at low temperatures demonstrate no change in saturation polarization, while at high temperatures a rise by approximately ~15% at 800°C was observed. The rise of the saturation polarization at high annealing temperatures is attributed to the de-wetting effect.

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8

Sun, Jining. "Deterministic fabrication of micro- and nano-structures by focused ion beam". Thesis, Heriot-Watt University, 2012. http://hdl.handle.net/10399/2528.

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9

Reinert, Tilo. "Focussed MeV-Ion Micro- and Nano-Beams in the Life Sciences". Doctoral thesis, Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-197802.

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This work presents the development of a sub-micron nuclear microprobe for applications in the life sciences. It includes quantitative trace element analysis with sub-micron spatial resolution, 2D- and 3D-microscopy of density distributions and the targeted irradiation of living cells with counted single ions. The analytical methods base on particle induced X-ray emission spectrometry (PIXE), Rutherford backscattering spectrometry (RBS), scanning transmission ion microscopy (STIM) and STIM-tomography. The specific development of the existing nuclear microprobe LIPSION led to an improved performance of the capabilities for trace element analysis. For sub-micron analysis the spatial resolution could be improved to 300 nm at a sensitivity of about 1 µg/g for metal ions in biological matrices; for a resolution of 1 µm the sensitivity was improved to 200 ng/g (3 µmol/l). This habilitation thesis comprises a short general introduction including the motivation to utilize focussed high energy ion beams, an overview on the applications and actual research fields. The introduction is followed by the basic principles of the equipments and analytical methods. An estimation of the limits of resolution for element analytical and single ion techniques is given for the Leipzig system. Thereafter, selected studies from different research areas are presented. The first presented application is a study from environmental air pollution research. It is demonstrated that the microscopic elemental analysis of single aerosol particles can be used to assess the contributions from different sources. A further example is the analysis of the distribution of nanoparticles in skin cross-sections for a risk assessment of the applications of nanosized physical UV-filters in cosmetic products. The risk assessment is followed by the micro-analysis of trace elements, especially of bound metal ions, in brain sections on the cellular and sub-cellular level. After this the application of focussed MeV ion beams in low dose radiobiological research is presented. Finally, the analysis of 3D-density distributions by proton micro-tomography is demonstrated. A summary concludes on the applications and gives an outlook to further applications and methodological developments. The appendix comprises the relevant publications of the author
Die vorliegende Arbeit etabliert für Anwendungen in den Lebenswissenschaften den Einsatz hochfokussierter MeV-Ionenstrahlen für nuklear-mikroskopische Methoden der quantitativen Spurenelementanalyse, der 2D- und 3D-Dichtemikroskopie sowie für die gezielte Bestrahlung einzelner lebender Zellen für radiobiologische Experimente. Zur Anwendung kamen die Methoden ortsaufgelöste Protonen induzierte Röntgenfluoreszenzanalyse (particle induced X-ray emission - PIXE), Spektrometrie rückgestreuter Ionen (Rutherford backscattering spectrometry - RBS) und Rastertransmissionsionenmikroskopie (scanning transmission ion microscopy - STIM). Durch eine gezielte Weiterentwicklung des bestehenden Ionenstrahlmikroskops, der Hochenergie Ionennanosonde LIPSION, konnte die Ortsauflösung für Spurenelementanalyse auf unter 300 nm verbessert werden, beziehungsweise die Sensitivität für Metallionen in biologischen Proben auf unter 200 ng/g (3 µmol/l) bei einer Ortsauflösung von 1 µm verbessert werden. Die Habilitationsschrift umfasst eine kurze allgemeine Einleitung einschließlich der Motivation für den Einsatz fokussierter MeV-Ionenstrahlen sowie einen Überblick über die Anwendungsgebiete und aktuellen Forschungsschwerpunkte. Danach werden kurz die Grundlagen der Technik und Methoden vorgestellt, gefolgt von einer Abschätzung der Auflösungsgrenzen für Elementanalysen und Einzelionentechniken. Danach werden ausgewählte Anwendungen aus verschiedenen Forschungsgebieten vorgestellt. Das erstes Beispiel ist aus der Umweltforschung. Es wird dargestellt, wie mittels ortsaufgelöster Elementspektroskopie eine Abschätzung der Feinstaubbelastung nach Beiträgen einzelner Verursacherquellen erfolgen kann. Dann folgt als Beispiel eine ortsaufgelöste Analyse der Verteilung von Nanopartikeln aus Sonnencremes in Hautquerschnitten zur Risikoabschätzung der Anwendungen von Nanotechnologie in kosmetischen Produkten. Desweiteren werden Studien der Spurenelementverteilung, speziell der von gebundenen Metallionen, in Hirnschnitten auf zellulärer und subzellulärer Ebene erläutert. Das anschließende Beispiel erläutert die Anwendung niedriger Energiedosen in der Radiobiologie anhand des Beschusses einzelner lebender Zellen mit abgezählten einzelnen Ionen. Als letztes Beispiel wird die Anwendung hochfokussierter Ionenstrahlen für die Mikrotomographie gezeigt. Abschließend folgt eine zusammenfassende Bewertung der vorgestellten Anwendungen mit einem Ausblick auf weitere Anwendungen und methodische Entwicklungen. Der Arbeit sind die relevanten Veröffentlichungen mit Beteiligung des Autors als Anhang beigefügt

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10

Bin, Jianhui. "Laser-driven ion acceleration from carbon nano-targets with Ti:Sa laser systems". Diss., Ludwig-Maximilians-Universität München, 2015. http://nbn-resolving.de/urn:nbn:de:bvb:19-185199.

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Over the past few decades, the generation of high energetic ion beams by relativistic intense laser pulses has attracted great attentions. Starting from the pioneering endeavors around 2000, several groups have demonstrated muliti-MeV (up to 58 MeV for proton by then) ion beams along with low transverse emittance and ps-scale pulse duration emitted from solid targets. Owing to those superior characteristics, laser driven ion beam is ideally suitable for many applications. However, the laser driven ion beam typically exhibits a large angular spread as well as a broad energy spectrum which for many applications is disadvantageous. The utilization of nano-targets as ion source provides a number of advantages over micrometer thick foils. The presented PhD work was intended to investigate laser driven ion acceleration from carbon nano-targets and demonstrate the potential feasibility for biological studies. Two novel nano-targets are employed: nm thin diamond-like-carbon (DLC) foil and carbon nanotubes foam (CNF). Both are self-produced in the technological laboratory at Ludwig-Maximilians-Universität München. Well-collimated proton beams with extremely small divergence (half angle) of 2 degrees are observed from DLC foils, one order of magnitude lower as compared to micrometer thick targets. Two-dimensional particle-in-cellsimulations indicate a strong influence from the electron density distribution on the divergence of protons. This interpretation is supported by an analytical model. In the same studies, the highest maximum proton energy was observed with a moderate laser intensity as low as 5*10^18W/cm^2. Parallel measurements of laser transmission and reflection are used to determine laser absorption in the nano-plasma, showing a strong correlation to the maximum proton energy. This observation indicates significance of absorbed laser energy rather than incident laser intensity and is supported by an analytical model. The ion energy also depends on pulse duration, a reduced optimum pulse duration is found as compared to micrometer thick targets. This behavior is attributed to a reduction of transverse electron spread due to the reduction of thickness from micrometer to nanometer. These remarkable proton bunch characteristics enabled irradiating living cells with a single shot dose of up to 7 Gray in one nanosecond, utilizing the Advanced Titanium: sapphire LASer (ATLAS)system at Max-Planck-Institut of Quantum Optics (MPQ). The experiments represent the first feasibility demonstration of a very compact laser driven nanosecond proton source for radiobiological studies by using a table-top laser system and advanced nano-targets. For the purpose of providing better ion sources for practical application, particularly in terms of energy increase, subsequent experiments were performed with the Astra Gemini laser system in the UK. The experiments demonstrate for the first time that ion acceleration can be enhanced by exploiting relativistic nonlinearities enabled by micrometer-thick CNF targets. When the CNF is attached to a nm-thick DLC foil, a significant increase of maximum carbon energy (up to threefold) is observed with circularly polarized laser pulses. A preferable enhancement of the carbon energy is observed with non-exponential spectral shape, indicating a strong contribution of the radiation pressure to the overall acceleration. In contrast, the linear polarization give rise to a more prominent proton acceleration. Proton energies could be increased by a factor of 2.4, inline with a stronger accelerating potential due to higher electron temperatures. Three-dimensional (3D) particle-in-cell (PIC) simulations reveal that the improved performance of the double-layer targets (CNF+DLC) can be attributed to relativistic self-focusing in near-critical density plasma. Interestingly, the nature of relativistic non-linearities, that plays a major role in laserwakefield-acceleration of electrons, can also apply to the benefit of laser driven ion acceleration.

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11

Lubke, Mechthild. "Nano-sized transition metal oxide negative electrode materials for lithium-ion batteries". Thesis, University College London (University of London), 2018. http://discovery.ucl.ac.uk/10044227/.

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This thesis focuses on the synthesis, characterization and electrochemical evaluation of various nano-sized materials for use in high power and high energy lithium-ion batteries. The materials were synthesised via a continuous hydrothermal flow synthesis (CHFS) process, which is a single step synthesis method with many advantages including screening processes (chapter 5). Electrochemical energy storage is introduced in chapter 1, with a focus on high power and high energy negative electrode materials for lithium-ion batteries (and capacitors). Many different classes of materials are discussed with associated advantages and disadvantages. This is followed by an experimental section in chapter 2. Chapter 3 deals with the main question regarding why some high power insertion materials show a wider operational potential window than expected. The nature of this electrochemical performance is discussed and classified towards battery-like and supercapacitor-like behaviour. Chapter 4 deals with Nb-doped anatase TiO2, which was tested for high power insertion materials. The role of the dopant was discussed in a comprehensive study. Chapter 5 gives an excellent example how CHFS processes can help accurately answer a scientific question. In this case the question dealt with the impact of transition metal dopants on the electrochemical performance of SnO2. Since CHFS enables similar materials properties despite doping, the real impact could be investigated in a fair manner. Finally, chapter 6 shows a strategy of achieving higher energy simultaneously with high cycle life. Insertion materials are combined with alloying materials in a simple, single step synthesis and this showed increased capacity, which is essential for high energy.

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12

Vladov, Nikola. "Strategies for application of focused ion beams in micro and nano manufacturing". Thesis, University of Nottingham, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.664274.

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This thesis presents a new methodology for high precision nanoscale machining using Focused Ion Beam (FIB) processes. The methodology is supported by several novel models and methods developed during the PhD project. Gallium focused ion beam instruments are capable of processing virtually any material with a nanometre resolution. This has established FIB based instruments as invaluable specimen preparation tools in material science and circuit editing and failure analysis tools in the semiconductor industry. So far, the technique has had limited application in nano and micro- manufacturing, due to the high cost of the equipment and the long process cycle times required . Nonetheless in recent years it has been demonstrated that FIB can be a viable manufacturing technology if employed in the fabrication of high precision replication tools and it has the potential to replace existing electron and photon lithography techniques. One of the current problems is that the existing FIB procedures developed for material science are often not optimised for quality and efficiency or not applicable in manufacturing. A new machining methodology has been proposed that can be used as a guide to optimise FIB processes for improved efficiency and production quality. The methodology systematically looks into the material selection, the choice of gas precursor and the optimisation of the scanning parameters. To accomplish this several new models and methods are developed. A raster scanning model is proposed that links the probe current, the dwell time, the number of loops and the step with the key process parameters of refresh time, exposure time, dose, and dose distribution. Furthermore, a new term apparent beam size and a method for its measurement are suggested as an alternative to the commonly used "knife edge diameter". The apparent beam size is found to be material and precursor dependent and together with the overlap is accounted for as a key factor in the dose uniformity criterion formulated in the project.

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13

Jung, Daniel [Verfasser] y Dietrich [Akademischer Betreuer] Habs. "Ion acceleration from relativistic laser nano-target interaction / Daniel Jung. Betreuer: Dietrich Habs". München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2012. http://d-nb.info/1020790369/34.

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14

Martin, Andréa Joris Quentin. "Nano-sized Transition Metal Fluorides as Positive Electrode Materials for Alkali-Ion Batteries". Doctoral thesis, Humboldt-Universität zu Berlin, 2020. http://dx.doi.org/10.18452/21619.

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Übergangsmetallfluoridverbindungen sind sehr vielversprechende Kandidaten für die nächste Generation von Kathoden für Alkaliionenbatterien. Dennoch verhindern einige Nachteile dieser Materialklasse ihre Anwendung in Energiespeichermedien. Metallfluoride haben eine stark isolierende Wirkung, außerdem bewirken die Mechanismen beim Lade-/Entladevorgang, große Volumenänderungen und somit eine drastische Reorganisation des Materials, welche nur geringfügig umkehrbar ist. Um diese Nachteile zu reduzieren, werden in dieser Arbeit innovative Syntheserouten für die Umwandlung von Metallfluoridverbindungen sowie deren Anwendung in Alkaliionenbatterien vorgestellt. Im ersten Teil werden MFx Verbindungen (M = Co, Fe; x = 2 oder 3) untersucht. Diese Materialien zeigen eine hohe Ausgangskapazität aber nur bei sehr geringen C-Raten und zudem sehr geringe Zyklisierbarkeiten. Ex-situ-XRD und -TEM zeigen, dass die geringe Umkehrbarkeit der Prozesse hauptsächlich aus der Umwandlungsreaktion während des Be-/Entladens resultieren. Im zweiten Teil werden sowohl die Synthesen als auch die elektrochemischen Eigenschaften von Perowskiten aus Übergangsmetallfluoriden vorgestellt. NaFeF3 zeigt hierbei exzellente Leistungen und Reversibilitäten. Die Untersuchung der Mechansimen durch ex-situ und operando XRD während der Be- und Entladeprozesse hinsichtlich verschiedener Alkalisysteme zeigt, dass das kristalline Netzwerk über den Zyklus erhalten bleibt. Dies führt zur hohen Reversibilität und hohen Leistung selbst bei hohen C-Raten. Der Erhalt der Kristallstruktur wird durch elektrochemische Stabilisierung der kubischen Konformation von FeF3 ermöglicht, welche normalerweise erst bei hohen Temperaturen (400 °C) beobachtet wird und durch geringere Reorganisationen innerhalb des Kristallgerüsts erklärt werden kann. Ähnliche elektrochemische Eigenschaften können für KFeF3 und NH4FeF3 beobachtet werden, wobei erstmalig von Ammoniumionen als Ladungsträger in Alkaliionensystemen berichtet wird.
Metal fluoride compounds appear as very appealing candidates for the next generation of alkali-ion battery cathodes. However, many drawbacks prevent this family of compounds to be applicable to storage systems. Metal fluorides demonstrate a high insulating character, and the mechanisms involved during the discharge/charge processes atom engender large volume changes and a drastic reorganization of the material, which induces poor reversibility. In order to answer these problematics, the present thesis reports the elaboration of innovative synthesis routes for transition metal fluoride compounds and the application of these fluoride materials in alkali-ion battery systems. In a first part, MFx compounds (M = Co, Fe; x = 2 or 3) are studied. Those compounds exhibit high initial capacity but very poor cyclability and low C-rate capabilities. Ex-situ X-ray diffraction and transmission electron microscopy demonstrate that the low reversibility of the processes is mainly due to the conversion reaction occurring during their discharge/charge. In the second part, the syntheses of transition metal fluoride perovskites are reported, as well as their electrochemical properties. NaFeF3 demonstrates excellent performances and reversibility. The study of the mechanisms occurring during its charge/discharge processes towards different alkali systems by ex-situ and operando X-ray diffraction reveals that its crystalline framework is maintained along the cycles, resulting in high reversibility and excellent C-rate performance. This retention of the crystal framework is possible by an electrochemical stabilization of a cubic conformation of FeF3, which is usually only observable at high temperature (400 °C), and can be explained by lower reorganizations within the crystal framework. Similar electrochemical properties could be observed for KFeF3 and NH4FeF3, where ammonium ions are reported for the first time as a charge carrier in alkali-ion systems.

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15

Qin, Zhenpeng. "Modeling of Ion Transport for Micro/Nano Size Particles in Coulter Counter Application". University of Akron / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=akron1240858653.

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16

Henriques, Alexandra J. "Nano-Confined Metal Oxide in Carbon Nanotube Composite Electrodes for Lithium Ion Batteries". FIU Digital Commons, 2017. http://digitalcommons.fiu.edu/etd/3169.

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Lithium ion batteries (LIB) are one of the most commercially significant secondary batteries, but in order to continue improving the devices that rely on this form of energy storage, it is necessary to optimize their components. One common problem with anode materials that hinders their performance is volumetric expansion during cycling. One of the methods studied to resolve this issue is the confinement of metal oxides with the interest of improving the longevity of their performance with cycling. Confinement of metal oxide nanoparticles within carbon nanotubes has shown to improve the performance of these anode materials versus unconfined metal oxides. Here, electrostatic spray deposition (ESD) is used to create thin films of nano-confined tin oxide/CNT composite as the active anode material for subsequent property testing of assembled LIBs. This thesis gives the details of the techniques used to produce the desired anode materials and their electrochemical characterization as LIB anodes.

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17

Llobet, Sixto Jordi. "Focused ion beam implantation as a tool for the fabrication of nano electromechanical devices". Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/384934.

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La tesi doctoral titulada “Focused ion beam implantation as a tool for the fabrication of nano electromechanical devices” aborda el repte de la fabricació de ressonadors nano-mètrics des d’una nova òptica basada en la implantació iònica mitjançant un feix de ions focalitzat (FIB). Aquest nou mètode permet fabricar nano-dispositius suspesos funcionals, des del punt de vista elèctric i mecànic, sense necessitat d’utilitzar resina d’una forma i) ràpida i simple, només son necessàries tres etapes de fabricació; ii) flexible, permet definir dispositius amb gran llibertat geomètrica; iii) alta resolució, es demostra la fabricació de dispositius suspesos de 4 μm de longitud per 10 nm de diàmetre; iv) reproduïble i v) compatible amb la tecnologia CMOS. Partint d’un xip de silici o SOI (silici - diòxid de silici - silici), el mètode de fabricació comença amb un procés d’implantació FIB on es defineixen les estructures i les connexions elèctriques del dispositiu. El segon pas consisteix en el gravat humit del silici, on s’ataca el silici que no està protegit per la implantació FIB, permetent la suspensió o alliberació dels dispositius. En aquest estadi, on les estructures ja estan definides, el silici és amorf, conté gal·li i no és elèctricament funcional (ρ ~1 Ω·m). El darrer pas consisteix en un tractament tèrmic a alta temperatura fins a 1000ºC, en ambient de nitrogen i amb un precursor sòlid de bor on es propicia la recristal·lització del silici formant nano-cristalls, dopar el silici amb bor (tipus p) i eliminar el gal·li. Aquest tractament a alta temperatura, on les estructures no son oxidades, permet obtenir dispositius elèctricament funcionals (ρ ~10-4 Ω·m). Els principals resultats obtinguts es poden classificar en tres àmbits: Investigació de l’efecte de la implantació amb ions gal·li en el silici, pel que fa tant a aspectes de processament com de propietats nanoelectromecàniques del material. En aquest treball hem caracteritzat l’estructura del material en les diferents etapes de fabricació i hem caracteritzat elèctrica i electromecànicament els dispositius finals obtinguts pel mètode descrit. Desenvolupament i optimització del procés de fabricació, especialment pel que respecte al control de dimensions i a la combinació amb altres processos Es mostra el treball realitzat en la optimització dels diferents paràmetres de fabricació, des de la posta a punt de la dosi d’ions fins a la selectivitat del gravat. A través del disseny de les estructures es pot establir estratègies per controlar i minimitzar els efectes d’”under-etching” en el silici, a través de la definició d’estructures de compensació, i també evitar el col·lapse de les estructures més llargues, degut a les tensions superficials que es produeixen durant els processos de gravat humit, fabricant pilars per sostenir les estructures. Aquest mètode de fabricació permet obtenir dispositius a mida convertint-lo en una eina versàtil de prototipatge i de fabricació petites quantitats, que permet aconseguir dispositius de dimensions nano-mètriques per a l’experimentació acadèmica i científica. Investigació de les propietats electròniques, mecàniques i electromecàniques dels dispositius, i concretament en el cas de nanofils de silici suspesos que es poden aplicar com a ressonadors mecànics d’altra freqüència o transistors d’un sol forat. Hem pogut fabricar ressonadors de diferents geometries que ens ha permès estudiar i demostrar la relació que existeix entre la simetria/asimetria dels dispositius i el senyal piezoresistiu mesurat durant la transducció electromecànica. Hem investigat i fabricat transistors d’efecte camp ultra-fins (10 ~ 15 nm) i transistors suspesos on les característiques elèctriques a baixa temperatura mostren efectes de “Coulomb blockade” gracies als nano-cristalls que es formen, dins dels nano-fils de silici suspesos, durant l’etapa de tractament tèrmic.
The thesis entitled “Focused ion beam implantation as a tool for the fabrication of nano electromechanical devices” aboard the challenge of the fabrication of nanometric resonators from a new approach based on ion implantation by a focused ion beam (FIB) . This new method allows the fabrication of functional suspended nanodevices, from the electrical and mechanical point of view, without using any resist. This method is i) fast and simple, where only three steps are needed; ii) flexible, it is feasible the definition of structures of different shape; iii) high resolution, it is demonstrated the fabrication of 4 μm length and 10 nm diameter suspended devices; iv) reproducible and v) CMOS compatible. The starting point is a silicon or SOI (silicon – silicon dioxide – silicon) chip. The fabrication approach starts with a FIB implantation process where the structures and the electrical connections of the device are defined. The second step consists on silicon wet etching, where silicon that is not protected by the FIB implantation is etched, allowing the release of the devices. The defined structures are made of amorphous silicon, they contains gallium and they are not functional electrically (ρ ~1 Ω·m). The last step consists on diffusive boron doping at high temperature (up to 1000ºC) in a boron environment, where it is promoted the recrystallization of silicon forming nanocrystals, the boron doping (p type) of silicon and the removal of gallium. In this last step at high temperature the structures are not oxidized obtaining electrically functional devices (ρ ~10-4 Ω·m). The principal results can be classified in three areas: Investigation of the effect of gallium ion implantation onto silicon from the process and nanoelectromechanical material properties point of view. In this work the material structure in the different fabrication steps has been characterized, as well as the electrical and electromechanical properties of the final devices obtained by the described method. Development and optimization of the fabrication process, especially controlling the dimensions and the combination with other fabrication processes. The work done in the optimization of the different fabrication parameters are shown, from the tuning of the ion dosage to the etching selectivity. It is possible to stablish design strategies to control and minimize the under-etching effects onto silicon, as well as to avoid the collapse of long structures, that are the result of the superficial sticking produced during the wet etching processes, by the fabrication of sustaining posts. That method permits to obtain customized devices. It is a versatile prototyping method that allows the fabrication of small batches of devices of nanometric dimensions that can be employed for the scientific and academic experimentation. Investigation of the electronical, mechanical and electromechanical properties of the devices, specifically suspended silicon nanowires that can be employed as high frequency mechanical resonators or single hole transistors. We fabricated resonators of different geometries for the study and demonstration of the relation between the geometrical symmetry/asymmetry of the devices and the piezoresistive signal measured during the electromechanical transduction. We investigated and fabricated ultra-thin field effect transistors (10 ~ 15 nm) and suspended transistors that exhibits Coulomb blockade electrical characteristics at low temperature thanks to the nanocrystals that are grown during the high temperature fabrication step.

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18

Ross, Francis L. (Francis LaFayette) 1968. "Nano-cellular microstructure evolution in ion-induced chemical vapor deposition (II-CVD) of copper". Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/29971.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2003.
Includes bibliographical references (p. 179-181).
A systematic investigation of the microstructure produced in ion-induced chemical vapor deposition (11-CVD) of copper from copper(I)hexafluoroacetylacetonatevinyltrimethylsilane (Cu(I)hfacVTMS) gas precursor is reported. II-CVD involves the ion-driven decomposition of Cu(l)hfacVTMS and subsequent deposition of copper films at ambient temperature. The thin films were grown with the aid of a broad beam Kaufman source in a "multibeam apparatus", which allowed monitoring of experimental conditions - growth rate, temperature, ion beam flux, ion beam energy and gas precursor flux. Deposition temperatures ranged from room temperature to 100⁰C. The desirable operation range is the "ion-flux-limited regime", in which sufficient precursor flux allows the growth rate to scale with the ion flux. Plan-view TEM and cross-sectional TEM (XTEM) show that the film develops a characteristic cellular microstructure of continuous crystalline copper columns (15 nm diameter) surrounded by an amorphous phase containing both carbon impurity and copper. The column diameter increases with temperature but is not affected by the growth rate for temperatures up to 60⁰C. At higher temperatures, the growth mechanism is not purely ion driven due to the onset of thermal CVD. However, quantitative XPS (x-ray photoelectron spectroscopy) shows that the film purity not only increases with substrate temperature, but also increases with decreasing growth rate due to the kinetics of byproduct desorption. STEM-EDS (scanning transmission electron microscopy - energy dispersive x-ray spectroscopy) shows that the intercolumnar spaces contain more copper at lower growth rates for a given substrate temperature. Hydrogen-atom-assisted II-CVD effectively removed all carbonaceous impurity to within the detection limit of XPS. The cellular microstructure is not observed in these films; however, deposition at 100⁰C produces films that still retain a columnar structure even though the atomic fraction of carbon is only [approximately] 0.5%. This high temperature growth process has a mixed mechanism where the ion beam flux also enhances the kinetics of the thermal CVD process. The microstructure evolution is modeled as a cellular growth process that is controlled by surface transport of carbon impurity. The cellular mechanism is corroborated by the sharp transitions
(cont.) observed in XTEM for a change in deposition conditions. The surface diffusion is not only a function of temperature but also the ion flux. This explains why the column diameter remains independent of growth rate at constant temperature. The model assumes an approximately linear dependence of the diffusion constant's pre-exponential factor with ion the flux. The model predicts column diameters that are in good agreement with experimental data. The model was designed to integrate with Chiang's kinetic model to provide a foundation for depositing controlled microstructures using I-CVD. The work presented here demonstrates the possibility of growing controlled nano-cellular microstructures using a low voltage broad ion beam at or near ambient temperature. Films with such nano-cellular structures are expected to have highly anisotropic properties that could be used in a variety of applications, including magnetics ...
by Francis L. Ross, III.
Ph.D.

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19

Llobet, Sixto Josep. "Focused ion beam implantation as a tool for the fabrication of nano electromechanical devices". Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/384934.

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La tesi doctoral titulada “Focused ion beam implantation as a tool for the fabrication of nano electromechanical devices” aborda el repte de la fabricació de ressonadors nano-mètrics des d’una nova òptica basada en la implantació iònica mitjançant un feix de ions focalitzat (FIB). Aquest nou mètode permet fabricar nano-dispositius suspesos funcionals, des del punt de vista elèctric i mecànic, sense necessitat d’utilitzar resina d’una forma i) ràpida i simple, només son necessàries tres etapes de fabricació; ii) flexible, permet definir dispositius amb gran llibertat geomètrica; iii) alta resolució, es demostra la fabricació de dispositius suspesos de 4 μm de longitud per 10 nm de diàmetre; iv) reproduïble i v) compatible amb la tecnologia CMOS. Partint d’un xip de silici o SOI (silici - diòxid de silici - silici), el mètode de fabricació comença amb un procés d’implantació FIB on es defineixen les estructures i les connexions elèctriques del dispositiu. El segon pas consisteix en el gravat humit del silici, on s’ataca el silici que no està protegit per la implantació FIB, permetent la suspensió o alliberació dels dispositius. En aquest estadi, on les estructures ja estan definides, el silici és amorf, conté gal·li i no és elèctricament funcional (ρ ~1 Ω·m). El darrer pas consisteix en un tractament tèrmic a alta temperatura fins a 1000ºC, en ambient de nitrogen i amb un precursor sòlid de bor on es propicia la recristal·lització del silici formant nano-cristalls, dopar el silici amb bor (tipus p) i eliminar el gal·li. Aquest tractament a alta temperatura, on les estructures no son oxidades, permet obtenir dispositius elèctricament funcionals (ρ ~10-4 Ω·m). Els principals resultats obtinguts es poden classificar en tres àmbits: Investigació de l’efecte de la implantació amb ions gal·li en el silici, pel que fa tant a aspectes de processament com de propietats nanoelectromecàniques del material. En aquest treball hem caracteritzat l’estructura del material en les diferents etapes de fabricació i hem caracteritzat elèctrica i electromecànicament els dispositius finals obtinguts pel mètode descrit. Desenvolupament i optimització del procés de fabricació, especialment pel que respecte al control de dimensions i a la combinació amb altres processos Es mostra el treball realitzat en la optimització dels diferents paràmetres de fabricació, des de la posta a punt de la dosi d’ions fins a la selectivitat del gravat. A través del disseny de les estructures es pot establir estratègies per controlar i minimitzar els efectes d’”under-etching” en el silici, a través de la definició d’estructures de compensació, i també evitar el col·lapse de les estructures més llargues, degut a les tensions superficials que es produeixen durant els processos de gravat humit, fabricant pilars per sostenir les estructures. Aquest mètode de fabricació permet obtenir dispositius a mida convertint-lo en una eina versàtil de prototipatge i de fabricació petites quantitats, que permet aconseguir dispositius de dimensions nano-mètriques per a l’experimentació acadèmica i científica. Investigació de les propietats electròniques, mecàniques i electromecàniques dels dispositius, i concretament en el cas de nanofils de silici suspesos que es poden aplicar com a ressonadors mecànics d’altra freqüència o transistors d’un sol forat. Hem pogut fabricar ressonadors de diferents geometries que ens ha permès estudiar i demostrar la relació que existeix entre la simetria/asimetria dels dispositius i el senyal piezoresistiu mesurat durant la transducció electromecànica. Hem investigat i fabricat transistors d’efecte camp ultra-fins (10 ~ 15 nm) i transistors suspesos on les característiques elèctriques a baixa temperatura mostren efectes de “Coulomb blockade” gracies als nano-cristalls que es formen, dins dels nano-fils de silici suspesos, durant l’etapa de tractament tèrmic.
The thesis entitled “Focused ion beam implantation as a tool for the fabrication of nano electromechanical devices” aboard the challenge of the fabrication of nanometric resonators from a new approach based on ion implantation by a focused ion beam (FIB) . This new method allows the fabrication of functional suspended nanodevices, from the electrical and mechanical point of view, without using any resist. This method is i) fast and simple, where only three steps are needed; ii) flexible, it is feasible the definition of structures of different shape; iii) high resolution, it is demonstrated the fabrication of 4 μm length and 10 nm diameter suspended devices; iv) reproducible and v) CMOS compatible. The starting point is a silicon or SOI (silicon – silicon dioxide – silicon) chip. The fabrication approach starts with a FIB implantation process where the structures and the electrical connections of the device are defined. The second step consists on silicon wet etching, where silicon that is not protected by the FIB implantation is etched, allowing the release of the devices. The defined structures are made of amorphous silicon, they contains gallium and they are not functional electrically (ρ ~1 Ω·m). The last step consists on diffusive boron doping at high temperature (up to 1000ºC) in a boron environment, where it is promoted the recrystallization of silicon forming nanocrystals, the boron doping (p type) of silicon and the removal of gallium. In this last step at high temperature the structures are not oxidized obtaining electrically functional devices (ρ ~10-4 Ω·m). The principal results can be classified in three areas: Investigation of the effect of gallium ion implantation onto silicon from the process and nanoelectromechanical material properties point of view. In this work the material structure in the different fabrication steps has been characterized, as well as the electrical and electromechanical properties of the final devices obtained by the described method. Development and optimization of the fabrication process, especially controlling the dimensions and the combination with other fabrication processes. The work done in the optimization of the different fabrication parameters are shown, from the tuning of the ion dosage to the etching selectivity. It is possible to stablish design strategies to control and minimize the under-etching effects onto silicon, as well as to avoid the collapse of long structures, that are the result of the superficial sticking produced during the wet etching processes, by the fabrication of sustaining posts. That method permits to obtain customized devices. It is a versatile prototyping method that allows the fabrication of small batches of devices of nanometric dimensions that can be employed for the scientific and academic experimentation. Investigation of the electronical, mechanical and electromechanical properties of the devices, specifically suspended silicon nanowires that can be employed as high frequency mechanical resonators or single hole transistors. We fabricated resonators of different geometries for the study and demonstration of the relation between the geometrical symmetry/asymmetry of the devices and the piezoresistive signal measured during the electromechanical transduction. We investigated and fabricated ultra-thin field effect transistors (10 ~ 15 nm) and suspended transistors that exhibits Coulomb blockade electrical characteristics at low temperature thanks to the nanocrystals that are grown during the high temperature fabrication step.

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20

Li, Lan. "Synthesis of LiCoO2 Nano crystals and their blends with polymers for thin Li-ion batteries /". Aachen Mainz, 2005. http://deposit.ddb.de/cgi-bin/dokserv?id=2708090&prov=M&dok_var=1&dok_ext=htm.

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21

Suder, Su Li. "Fabrication of nano-scale silicon-on-insulator substrates using ion split and etch back technologies". Thesis, Queen's University Belfast, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.437651.

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22

Davids, Wafeeq. "Consolidated Nanomaterials Synthesized using Nickel micro-wires and Carbon Nanotubes". Thesis, University of the Western Cape, 2007. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_9685_1264387931.

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23

Shim, Hwirim [Verfasser]. "Nano-design of metal oxide electrodes for Li- and Na-ion hybrid energy storage / Hwirim Shim". Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2020. http://d-nb.info/1224883608/34.

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24

Esaki, Shogo. "Cycle performance improvement of LiMn2O4 cathode material for lithium ion battery by formation of “Nano Inclusion”". Kyoto University, 2016. http://hdl.handle.net/2433/215650.

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著作権、出典、利用制限の表示を出版社より求められている。
Kyoto University (京都大学)
0048
新制・課程博士
博士(エネルギー科学)
甲第19824号
エネ博第330号
新制||エネ||66(附属図書館)
32860
京都大学大学院エネルギー科学研究科エネルギー基礎科学専攻
(主査)准教授高井茂臣, 教授萩原理加, 教授佐川尚
学位規則第4条第1項該当

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25

Le, Van Khu. "Préparation par voie électrochimique de nano-poudres de carbone en milieu carbonates alcalins fondus". Paris 6, 2009. http://www.theses.fr/2009PA066072.

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Des nano-poudres de carbone (5 - 50nm) ont été préparées par électro-réduction d’un mélange eutectique fondu Li2CO3-Na2CO3-K2CO3 entre 450°C et 700°C. Les mécanismes réactionnels mis en jeu ont été étudiés sur électrode en C vitreux et en Ni. Les analyses physico-chimiques ont mis en évidence la présence de phases amorphes et cristallisées. Les poudres possèdent des aires spécifiques très élevées (1315 m2/g) du fait de l’abondante micro et mésoporosité. Les poudres ont été utilisées comme matériaux hôtes anodiques pour accumulateurs lithium-ion dans différents électrolytes notamment le PC pur pour lequel des capacités réversibles de l'ordre de 430 mAh/g ont pu être obtenues. Les poudres de carbone ont également été testées comme matériau d’électrode négative pour condensateur électrochimique hybride C/MnO2 en milieu aqueux neutre. Des capacités de 122 F/g ont été enregistrées. Enfin, une approche exploratoire a été menée en vue de la synthèse de composés mixtes C-Ni et C-Sn par électrolyse du mélange de carbonates fondus contenant des ions Ni2+ ou Sn2+. Des particules de très petites tailles (5-10 nm) ont ainsi pu être mises en évidence

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26

Bin, Jianhui [Verfasser] y Jörg [Akademischer Betreuer] Schreiber. "Laser-driven ion acceleration from carbon nano-targets with Ti:Sa laser systems / Jianhui Bin. Betreuer: Jörg Schreiber". München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2015. http://d-nb.info/107545672X/34.

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27

Martin, Andréa Joris Quentin [Verfasser]. "Nano-sized Transition Metal Fluorides as Positive Electrode Materials for Alkali-Ion Batteries / Andréa Joris Quentin Martin". Berlin : Humboldt-Universität zu Berlin, 2020. http://d-nb.info/1220690406/34.

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28

Wheatland, Jonathan Antony Thomas. "Characterising the multi-scale properties of flocculated sediment by X-ray and focused ion beam nano-tomography". Thesis, Queen Mary, University of London, 2017. http://qmro.qmul.ac.uk/xmlui/handle/123456789/25984.

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The hydrodynamic behaviour of fine suspended aqueous sediments, and stability of the bedforms they create once settled, are governed by the physical properties (e.g., size, shape, porosity and density) of the flocculated particles in suspension (flocs). Consequently, accurate prediction of the transport and fate of sediments and of the nutrients and pollutants they carry depends on our ability to characterise aqueous flocs. Current research primarily focuses on characterising flocs based on their external gross-scale (>1 μm) properties (e.g., gross morphology, size and settling velocity) using in situ techniques such as photography and videography. Whilst these techniques provide valuable information regarding the outward behaviour of flocculated sediment (i.e. transport and settling), difficulties associated with extracting 3D geometries from 2D projections raises concerns regarding their accuracy and key parameters such as density can only be estimated. In addition, they neglect to inform on the internal micro- and nano-scale structure of flocs, responsible for much of their behaviour and development. Transmission electron microscope (TEM) and environmental electron microscope may be used to obtain nano-scale information in, essentially, 2D but there is a large scale gap between this information and the macro-scale of optical techniques. To address this issue this study uses 3D tomographic imaging over a range of spatial scales. Whilst commonly used in materials science and the life sciences, correlative tomography has yet to be applied in the environmental sciences. Threading together 3D Xray micro-computed tomography (X-ray μCT) and focused ion beam nano-tomography (FIBnt) with 2D TEM makes material characterisation from the centimetre to nanometre-scale possible. Here, this correlative imaging strategy is combined with a non-destructive stabilisation procedure and applied to the investigation of flocculated estuarine sediment, enabling the multi length-scale properties of flocs to be accurately described for the first time. This work has demonstrated that delicate aqueous flocs can be successfully stabilised via a resin embedding process and contrasted for both electron microscopy and X-ray tomography imaging. The 3D information obtained can be correlated across all length-scales from nm to mm revealing new information about the structure and morphology of flocs. A new system of characterising floc structure can be defined based on the association of particles and their stability in the structure rather than simply their size. This new model refutes the postulate that floc structures are fractal in nature.

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29

Dong, Bin. "Controllable synthesis for fabrication of micro/nano-structured mesoporous precursor particles for high performance lithium-ion batteries". Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/52091/.

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Increasingly global warming and air pollution caused by the consumption of fossil fuel have imposed the priority of using green energy. As a result, the use of rechargeable lithium-ion batteries (LIBs) has increased rapidly Olivine-structured LiFePO4 is considered as one of the most promising positive electrode materials owing to its significant advantages of nontoxicity, low cost of raw materials, good structural stability at high temperature, excellent safety performance, and relatively high theoretical specific capacity (170 mAhg-1) with a flat discharge-charge potential (3.45V vs. Li+/Li). Therefore, LiFePO4 battery becomes a reliable material for energy storage system used in hybrid electric vehicles (HEVs), full electric vehicles (EVs), plug-in hybrid electric vehicles (PHEVs), and portable devices. However, the poor rate performance of LiFePO4, resulting from its intrinsic low Li+ diffusivity (10-17 to 10-14 cm2s-1) and low electronic conductivity (10-9 to 10-8 S cm-1), has become a technical bottleneck to confine its widely practical applications. Following previous studies, a systematic study on controllable preparation of LiFePO4 positive electrode material with nanoscale size, or hierarchical micro/nano mesoporous structure has been carried out using various synthesis methods, including impinging stream reaction (ISR), ultrasonic-intensified impinging stream reaction (UISR), two-step co-precipitation method, and two-step hydrothermal method (UIHT). The physical and chemical properties of as-synthesized products are measured by XRD, FTIR, SEM, TEM, BET, Mastersizer, CV, and charge-discharge test. Based on these observations, the relationship among particle morphology, electrochemical performance, and impacts of fluid dynamics is evaluated in this work.

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30

Buckingham, Andrew Roger. "Modifying the magnetic properties of Laves phase intermetallic multilayers and films by nano-patterning and ion implantation". Thesis, University of Southampton, 2010. https://eprints.soton.ac.uk/161177/.

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Since the pioneering work of Kneller & Hawig and Skomski & Coey some 20 years ago, the topic of exchange springs has received considerable attention. Exchange springs, systems where thin hard and soft magnetic layers are alternately arranged in multilayer stacks, provide great potential in improving the performance of a wide range of devices, from permanent hard magnets and microelectromechanical sensors and actuators, to magnetoresistive random access memory and permanent magnetic data storage. Artificial structuring on the nano-scale will be beneficial in improving the functionality of exchange spring systems in all of these areas. In this work, two distinctly different routes to nano-structuring in epitaxially grown rare earth – iron (REFe2) films and exchange spring materials are described. Namely i) electron beam lithography and Ar+ ion milling to define three-dimensional nano-scale structures, and ii) ion implantation to directly alter the crystalline structure of the material at the atomic-scale. Nano-scale elements defined in REFe2 exchange spring materials are presented, providing not only the first demonstration of nano-structuring in these materials, but also the successful implementation of electron beam lithography and Ar+ ion milling on these novel systems. Nano-scale patterning confirms the suitability of the REFe2 exchange spring materials as excellent candidates for magnetic data storage media, since they remain relatively unaffected by nano-structuring, retaining their thermal stability and comparatively small coercivity. Ar+ ion implantation is shown to be effective at artificial structuring on the atomic-scale. In addition, energetic Ar+ ions have been successfully used to accurately control the easy and hard axes of magnetization within epitaxial YFe2 and DyFe2 films and a DyFe2 / YFe2 exchange spring multilayer. At a fluence of ~ 1017 Ar+ ions cm-2, the magnetoelastic anisotropy (dominant at room temperature in the epitaxially grown films) is reduced to such an extent that the intrinsic magnetocrystalline anisotropy begins to dominate. Thus Ar+ ion implantation serves to alter the easy and hard axes of magnetization, rotating them through 90°. Such behaviour is clearly evident in hysteresis loops obtained by both the magneto optical Kerr effect and vibrating sample magnetometry, and is further confirmed by micromagnetic modelling. The reduction in magnetoelastic anisotropy is attributed to energetic Ar+ ions causing RE atoms to relax to their unstrained lattice positions, thereby relieving the strain responsible for the magnetoelastic anisotropy. This interpretation is confirmed by X-ray diffraction measurements.

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31

Wilkening, Martin. "From Ultrafast to Extremely Slow Li Ion Dynamics in (Nano-)crystalline Solids ― Dimensionality Effects and Structural Disorder". Diffusion fundamentals 21 (2014) 8, S.1-2, 2014. https://ul.qucosa.de/id/qucosa%3A32400.

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32

Li, Rong. "Preparation and ion conductivity of nano to micron grains size Bi2O3-Ln2O3 (Ln=Dy, Y, Er) ceramics". Thesis, Lille 1, 2009. http://www.theses.fr/2009LIL10141/document.

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L’objectif de ce travail était l’étude de l’effet de la taille des grains de céramiques à base d’oxyde de bismuth sur les propriétés de conduction ionique. Avec pour objectif la préparation de céramiques denses avec des grains de taille nanométrique, des poudres de composition (Bi2O3)0.75(Dy2O3)0.25, (Bi2O3)0.75(Er2O3)0.25, (Bi2O3)0.75(Y2O3)0.25 et (Bi2O3)0.75(Er2O3)0.125(Y2O3)0.125 ont été préparées avec succès par une méthode de dosage en retour. Des poudres avec des grains mono-cristallins d’environ 20 nm ont été obtenues, à partir desquelles, des céramiques denses ont ensuite été préparées par frittage conventionnel et par « Spark Plasma Sintering ». Par les deux méthodes, des céramiques de densités relatives supérieures à 94% sont obtenues. Par SPS, la taille des grains est de 20nm seulement. Elle varie de 60 à 500nm par frittage conventionnel pour lequel une croissance des grains contrôlée par le transport de matière aux joints de grain est démontrée.L’effet de la taille des grains sur la conductivité a finalement été étudié par spectroscopie d’impédance. Une diminution de la conductivité avec la taille des grains est généralement observée, probablement due au caractère bloquant des joints de grain. En revanche, la composition (Bi2O3)0.75(Dy2O3)0.25 avec des grains de 22nm présente des conductivités au dessus de celles de la céramique de même composition avec des grains de 62nm et une meilleure séparation des réponses dues aux grains et aux joints de grains. Pour des tailles de grains aussi faibles, les couches d’espace de charge entre les grains ne peuvent plus être négligées et le phénomène observé est probablement dû à une augmentation de la conductivité dans ces couches
The aim of this work was the study of the effect of the grain size of bismuth based oxide ceramics on the ionic properties. With the aim to prepare dense ceramics with controlled grain size at the nano-scale, nano-powders of (Bi2O3)0.75(Dy2O3)0.25, (Bi2O3)0.75(Er2O3)0.25, (Bi2O3)0.75(Y2O3)0.25 and (Bi2O3)0.75(Er2O3)0.125(Y2O3)0.125 compositions were successfully prepared by a reverse chemical titration method. As shown by XRD and TEM, after annealing for 3 hours at 500°C, powders with single crystal grains with size of about 20nm were obtained. At that stage, a b-form was evidenced for all compositions.Then, conditions of sintering were optimized. Two techniques were used: pressureless sintering in a conventional furnace and Spark Plasma Sintering (SPS). In both methods, it led to ceramics with relative density higher than 94%. The grain size was only 20nm by SPS. It ranges from 60nm to 500nm by conventional sintering, for which it was shown that the grain growth was controlled by mass transport through the grain boundaries. The effect of grain size on total ionic conductivity was studied by impedance spectroscopy for all compositions. For most compositions, a decrease of total ionic conductivity with grain size was observed due to a predominant blocking effect of grain boundary when grain size decreases. However (Bi2O3)0.75(Y2O3)0.25 with grain size of 22nm showed a better conductivity than ceramics with grain size of 62nm and a better separation of bulk and grain boundary response. At such a low size, the space charge layers effect between grains can not be neglected anymore and the observed increase in conductivity is likely the results of an increase of the conductivity in this space charge layers

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33

Franich, Rick y rick franich@rmit edu au. "Monte Carlo Simulation of Large Angle Scattering Effects in Heavy Ion Elastic Recoil Detection Analysis and Ion Transmission Through Nanoapertures". RMIT University. Applied Sciences, 2007. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080212.121837.

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Heavy Ion Elastic Recoil Detection Analysis (HIERDA) is a versatile Ion Beam Analysis technique well suited to multi-elemental depth profiling of thin layered structures and near-surface regions of materials. An existing limitation is the inability to accurately account for the pronounced broadening and tailing effects of multiple scattering typically seen in HIERDA spectra. This thesis investigates the role of multiple large angle scattering in heavy ion applications such as HIERDA, and seeks to quantify its contribution to experimental output. This is achieved primarily by the development of a computer simulation capable of predicting these contributions and using it to classify and quantify the interactions that cause them. Monte Carlo ion transport simulation is used to generate simulated HIERDA spectra and the results are compared to experimental data acquired using the Time of Flight HIERDA facility at the Australian Nuclear Science and Technology Organisat ion. A Monte Carlo simulation code was adapted to the simulation of HIERDA spectra with considerable attention on improving the modelling efficiency to reduce processing time. Efficiency enhancements have achieved simulation time reductions of two to three orders of magnitude. The simulation is shown to satisfactorily reproduce the complex shape of HIERDA spectra. Some limitations are identified in the ability to accurately predict peak widths and the absolute magnitude of low energy tailing in some cases. The code is used to identify the plural scattering contribution to the spectral features under investigation, and the complexity of plurally scattered ion and recoil paths is demonstrated. The program is also shown to be useful in the interpretation of overlapped energy spectra of elements of similar mass whose signals cannot be reliably separated experimentally. The effect of large angle scattering on the transmission of heavy ions through a nano-scale aperture mask, used to collimate an ion beam to a very small beam spot, is modelled using a version of the program adapted to handle the more complex geometry of the aperture mask. The effectiveness of nano-aperture collimation was studied for a variety of ion-energy combinations. Intensity, energy, and angular distributions of transmitted ions were calculated to quantify the degree to which scattering within the mask limits the spatial resolution achievable. The simulation successfully predicted the effect of misaligning the aperture and the beam, and the result has subsequently been observed experimentally. Transmitted ion distributions showed that the higher energy heavier ions studied are more effectively collimated than are lower energy lighter ions. However, there is still a significant probability of transmission of heavy ions with substantial residual energy beyond the perimeter of the aperture. For the intended application, ion beam lithography, these ions are likely to be problematic. The results indicate that medium energy He ions are the more attractive option, as the residual energy of scattered transmitted ions can be more readily managed by customising the etching process. Continuing research by experimentalists working in this area is proceeding in this direction as a result of the conclusions from this work.

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34

Ait, Salah Atmane. "Etude des phosphates lithiés en vue de leur utilisation comme électrodes positives pour le stockage d'énergie". Paris 6, 2007. http://www.theses.fr/2007PA066123.

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Aujourd’hui les batteries ion-lithium, qui équipent universellement les dispositifs électroniques portables (téléphone, ordinateurs, etc. ), sont des sources d’énergies irremplaçables. Ces sources d’énergie sont appelées à connaître de plus grands développements encore pour pouvoir répondre à des exigences nouvelles comme le fait de constituer les sources d’énergie des voitures électriques de demain et celles des véhicules électriques hybrides que les constructeurs commencent à proposer aux consommateurs. Les matériaux employés actuellement pour fabriquer les cathodes, des oxydes de lithium du type Li(Ni,Co)O2, sont trop chers pour être utilisés à une plus large échelle et ne pourront répondent aux demandes prévisibles. Le développement de nouvelles batteries ion-lithium, à partir de métaux de transition plus communs, sinon banals, que le Nickel et le Cobalt s’impose. Idéalement, celui qui répond le mieux à cette exigence et qui est le plus répandu sur notre planète c’est l’ion Fer et ce dernier peut être associé à une anode construite à base de graphite Dans ce contexte, et depuis les travaux de J. B. Goodenough et de ses collaborateurs, le LiFePO4 constitue un matériau particulièrement intéressant. Toute notre contribution porte sur la compréhension des propriétés physico-chimiques de ce matériau et de deux proches voisins polyphosphates et sur l’amélioration des performances électrochimiques de ces matériaux, lesquelles sont étroitement dépendantes des conditions d’élaboration et de synthèse. Ce mémoire se compose en quatre chapitres : Le premier chapitre présente une étude bibliographique sur quelques familles de matériaux potentiellement utilisables comme électrodes positives dans les batteries ion-lithium et la possibilité de substituer ces derniers par LiFePO4. Le chapitre 2 est donc consacré à l’analyse des méthodes de synthèses et de caractérisation des matériaux. Cette caractérisation a été réalisées à partir d’outils classiques, comme la diffraction des rayons X (DRX), la microscopie électronique à balayage (MEB), la spectroscopie infrarouge par transformée de Fourier (IRTF), la spectroscopie Raman (RS), la résonance paramagnétique électronique (RPE) et la magnétométrie SQUID. Le chapitre 3 est entièrement consacré à l’étude des propriétés de LiFePO4. Les mesures magnétiques ont révélé la présence de « nano-agrégats » de maghémite Fe2O3 et de Fe2P dans les échantillons préparés par voie sol-gel. La nature, la concentration et la taille de ces nano particules ont été estimées à partir d’un modèle décrivant un comportement « super-paramagnétique » où « super-ferromagnétique ». On démontre également que l’enrobage des particules de LiFePO4 avec une couche mince (30 nm d’épaisseur moyenne) de carbone amorphe élimine pratiquement toutes les phases parasites, en contribuant à réduire le fer, et permet d’optimiser les performances électrochimiques de ce matériau. Le chapitre 4 traite les propriétés des oxydes de types LiFe1,5P2O7 et LiFe2P3O10. Ces deux composés ont été synthétisés, leurs structures ont été caractérisées ainsi que leur propriétés magnétiques, enfin ils ont été testés comme matériau d’électrode positive dans des générateurs au lithium.

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35

Márik, Marian. "Pokročilé techniky vytváření mikro a nanosystémů pro senzoriku". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220083.

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The use of micro- and nanotechnologies is necessary in the development of advanced sensor systems. In this thesis few selected technologies were studied and tested on fabrication of creating two different systems for bioelectrical and electrochemical applications. For biolelectrical applications a chip with a pair of gold nanoelectrodes was designed and implemented. For electrochemical analysis a novel two electrode system was designed and realized, which should contribute by greater sensitivity and accuracy in amperometric detection compared with three-electrode systems in voltammetric analysis. The fabricated systems were tested and the results were discussed.

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36

Chang, Chih-Hsiang. "Proteomic studies on protein N-terminus and peptide ion mobility by nano-scale liquid chromatography/tandem mass spectrometry". Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/263596.

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37

Moore, Iain. "Single ion detection using FET based nano-sensors : a combined drift diffusion and Brownian dynamics 3D simulation study". Thesis, University of Glasgow, 2014. http://theses.gla.ac.uk/5136/.

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There is an ever increasing requirement for rapid sensing mechanisms for a variety of purposes – from blood analysis to gas detection. In order to allow large throughput, these devices must also be available at low cost per unit. One method which meets these criteria is the interfacing of biological and nano-scale semiconductor elements. Using modern CMOS processing, alongside further post processing, such devices can be created for a variety of purposes. However, development of these devices is expensive and in order to investigate possible structures, a simulation system is ideal. This work details the development, testing and utilisation of such a system. By combining two widely understood simulation methods – Brownian dynamics and drift diffusion – a mix of efficiency and accuracy is achieved. The introduction begins with a section detailing background to the field in order to set the work in context. The development and strict testing regime employed is then described. Initial simulations of a bio-nano interface are then presented with detection of ions though alterations in the drain current of a nominal 35 nm FET. This shows that there is a 5 nA/µm increase in drain current when an ion is moved through a 3 nm lipid layer which is suspended 15 nm above the oxide allowing identification of the period of traversal of the lipid layer. The final chapter indicates the successful detection of individual ions traversing a nano-pore in the presence of biologically significant ionic concentrations. The rate of change of drain current in the FET indicates a 4 σ signal during traversal with a background concentration of ions of 1 mM which allows clear identification of this individual event.

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38

Sreeramoju, Mahendra K. "PREPARATION, CHARACTERIZATION AND APPLICATIONS OF FUNCTIONALIZED CARBON NANO-ONIONS". UKnowledge, 2013. http://uknowledge.uky.edu/chemistry_etds/20.

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Carbon nano-onions (CNOs) discovered by Ugarte in 1992 are multi-layered fullerenes that are spherical analogs of multi-walled carbon nanotubes with diameters varying from 6 nm to 30 nm. Among the various methods of synthesis, CNOs prepared by graphitization of nanodiamonds (N-CNOs) and underwater electric arc of graphite rods (A-CNOs) are the subject of our research. N-CNOs are considered as more reactive than A-CNOs due to their smaller size, high curvature and surface defects. This dissertation focuses on structural analysis and surface functionalization of N- CNOs with diameters ranging from 6—10 nm. Synthetic approaches such as oleum- assisted oxidation, Freidel-Crafts acylation and Billups reductive alkylation were used to functionalize N-CNOs to improve their dispersion properties in aqueous and organic solvents. Functionalized N-CNOs were characterized using various techniques such as TGA, TG-MS, Raman spectroscopy and pH-titrimetry. We designed an experimental method to isolate polycyclic aromatic adsorbates formed on the surface of oleum oxidized N-CNOs (ON-CNOs) and characterized them. A-CNOs, on the other hand are bigger than N-CNOs with diameters ranging from 20—40 nm. In this dissertation, we discuss the preparation of graphene structures by unzipping of A-CNOs using KMnO4 as oxidizing agent. These graphene structures were characterized using powder X-ray diffraction, TGA, BET nitrogen adsorption/desorption studies and compressed powder conductivity. This dissertation also focuses on lithiation/delithiation studies of N-CNOs, A- CNOs and A-CNO-derived graphene structures to use them as negative electrode materials in lithium-ion batteries. The cycling performances of these materials at a charge/discharge rate of C/10 were discussed. The cycling performance of N-CNOs was tested at faster charge/discharge rate of C.

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39

Malik, Adnan Muhammad. "Development of High Aspect Ratio Nano-Focusing Si and Diamond Refractive X-ray optics using deep reactive ion etching". Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:588ca438-e4c6-4d51-8f13-30bcb3c437a3.

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This thesis is devoted to the development of nano-focusing refractive optics for high energy X-rays using planar microelectronic technology. The availability of such optics is the key for the exploitation of high brilliance third and fourth generation X-ray sources. Advancements in the quality of optics available are commensurate with advancements in the fabrication technology. The fabrication process directly influences the quality and performance, so must be understood and controlled. In the first part of this thesis, the development of high aspect ratio Si kinoform lenses is examined. It is shown that control of the re-entrance angle is critical for successful fabrication; in fact, a large re-entrance angle can destroy the lens during the fabrication process. Through an etch study, it was found that as aspect ratio increases, control of the re-entrance angle becomes harder. To control the re-entrance angle for very high aspect ratios, a novel approach based on sacrificial structures was proposed and initial results presented. The second part is dedicated to an experimental study of refractive lenses made from diamond. Due to its low atomic number, relatively high density and very high thermal conductivity, diamond is one of the most desirable lens materials for refractive X-ray optics. However, due to its extreme hardness, it is very difficult to structure into a form suitable for X-ray lenses. To overcome this difficulty a Si moulding technique was used and focusing down to a 400 nm wide spot was achieved. Several obstacles were encountered and successfully overcome. The hardest obstacle was to obtain selective void-free filling in the Si moulds. Several methods were investigated. A method based on a sacrificial oxide layer and an Electrostatic Self-Assembly process was found to be the most useful. The approach discovered in this thesis is not limited to X-ray lenses, but can be applied to a wide variety of high aspect ratio MEMS requiring void-free diamond filling and smooth sidewalls.

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40

Jiménez, Jiménez Diego Leonardo. "Gestión óptima de la energía de una nano-red para minimizar la degradación de un pack modular de baterías de ion-litio". Tesis, Universidad de Chile, 2018. http://repositorio.uchile.cl/handle/2250/169961.

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Tesis para optar al grado de Magíster en Ciencias de la Ingeniería, Mención Eléctrica
Los dispositivos de almacenamiento de energía en particular las baterías de ion-litio han sido ampliamente utilizados en aplicaciones como: electrónica de consumo, vehículos eléctricos y sistemas de potencia con el fin de proveer confiabilidad, seguridad, rentabilidad y eficiencia; por esta razón es necesario analizar distintas configuraciones de packs modulares de baterías de acuerdo a los requerimientos de cada aplicación. En este sentido el objetivo del presente trabajo es desarrollar e implementar una estrategia de control capaz de manejar inteligentemente la energía de un pack modular de baterías de ion-litio minimizando su degradación con respecto a una métrica de desempeño dentro de la operación de una nano-red. La gestión de la energía de la nano-red se hace a través de un despacho económico con alto nivel de penetración de energía renovable que considera el rango de oscilación del estado de carga del pack modular de baterías en el contexto de su degradación; con el fin de definir una combinación óptima de las unidades de generación al mínimo costo de operación y alimentando la demanda eléctrica. Las simulaciones del caso de estudio se llevan a cabo a través de una plataforma económica-degradación que contempla el almacenamiento real de cada batería del pack a través de la actualización de su energía máxima durante todo el horizonte de evaluación. La métrica de desempeño denominado Caso Base utiliza una batería de 100Ah para alimentar la demanda eléctrica de la nano-red por una autonomía energética de 8 horas como máximo, la cual es comparada versus todos los casos de estudio propuestos: Caso Sobredimensionado utiliza una batería de 150Ah, pack modular de 2 baterías analizado en dos casos de estudio: Caso A de (80-40Ah) y Caso B de (100-50Ah), pack modular de 3 baterías de (80-40-20Ah) bajo dos políticas operacionales de restricción del estado de carga diferentes (PO1 y PO2). En todos los casos de estudio la política operacional permite entregar la misma energía que la métrica de desempeño así como también el costo de inversión de todas las configuraciones es comparable. Finalmente los resultados muestran que todos los casos propuestos suministran la demanda eléctrica de la nano-red durante todo el horizonte de evaluación; destacando que todas las configuraciones logran una duración extra respecto a la métrica de desempeño. Por ejemplo el pack modular de 3 baterías PO1 presenta una duración extra en las tres baterías de 22, 16 y 30 meses respectivamente teniendo una inversión superior en 620 USD respecto al Caso Base. En consecuencia se puede concluir que la decisión final de selección del diseño modular obedece al criterio del ejecutor del proyecto y a la necesidad del sistema, de tal forma que si la inversión del pack modular es superior en el corto plazo la degradación de las baterías será menor en el largo plazo lo que permite generar mayor rentabilidad.

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41

Dhoubhadel, Mangal S. "Synthesis and Characterization of Ion Beam Assisted Silver Nanosystems in Silicon Based Materials for Enhanced Photocurrent Collection Efficiency". Thesis, University of North Texas, 2015. https://digital.library.unt.edu/ark:/67531/metadc799502/.

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In recent years a great deal of interest has been focused on the synthesis of transitional metal (e.g. Ag, Cu, Fe, Au) nanosystems at the surface to sub-surface regions of Si and SiO2 matrices for fundamental understanding of their structures as well as for development of technological applications with enhanced electronic and optical properties. The applications of the metal nanoparticle or nanocluster (NC) systems range from plasmonics, photovoltaic devices, medical, and biosensors. In all of these applications; the size, shape and distribution of the metallic NCs in the silicon matrix play a key role. Low energy ion implantation followed by thermal annealing (in vacuum or gas environment) is one of the most suitable methods for synthesis of NCs at near surfaces to buried layers below the surfaces of the substrates. This technique can provide control over depth and concentration of the implanted ions in the host matrix. The implanted low energy metal ions initially amorphizes the Si substrates while being distributed at a shallow depth near the substrate surface. When subject to thermal annealing, the implanted ions agglomerate to form clusters of different sizes at different depths depending upon the fluence. However, for the heavier ions implanted with high fluences (~1×1016 - 1×1017 atoms/cm2), there lies challenges for accurately predicting the distribution of the implanted ions due to sputtering of the surface as well as redistribution of the implants within the host matrix. In this dissertation, we report the investigation of the saturation of the concentration of the implanted ion species in the depth profiles with low energies (< 80 keV) metal ions (Ag and Au) in Si (100), while studying the dynamic changes during the ion implantation. Multiple low energies (30-80 keV) Ag ions with different fluences were sequentially implanted into commercially available Si wafers in order to facilitate the formation of Ag NCs with a wide ion distributions range. The light absorption profile according to different sizes of NCs at the near-surface layers in Si were investigated. We have investigated the formation of Ag NCs in the Si matrix as a function of implantation and thermal annealing parameters. The absorbance of light is increased in Ag implanted Si with a significant increase in the current collection in I-V (current-voltage) photo switching measurements. The experimental photovoltaic cells fabricated with the Ag implanted Si samples were optically characterized under AM (air mass) 1.5 solar radiation conditions (~1.0 kW/m2). An enhancement in the charge collection were measured in the annealed samples, where prominent Ag NCs were formed in the Si matrix compared to the as-implanted samples with the amorphous layer. The characterization techniques such as Rutherford Backscattering Spectroscopy, XPS-depth profiling, transmission electron microscopy, optical absorption, and I-V (current-voltage) photo switching measurements were employed to understand the underlying science in the observed properties. The results of these investigations are discussed in this research.

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42

Zheng, Ce. "Synthèse de nano-amas d'oxyde métallique par implantation ionique dans un alliage Fe10Cr de haute pureté". Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLS091/document.

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Les aciers ODS (Oxide Dispersed Strengthened Steels), renforcés par des dispersions de nano-oxydes métalliques (à base d'éléments Y, Ti et O), sont des matériaux prometteurs pour les réacteurs nucléaires de génération IV. La compréhension fine des mécanismes mis en jeu lors de la précipitation de ces nano-oxydes permettrait d'améliorer la fabrication et les propriétés mécaniques de ces aciers ODS, avec un fort impact économique en vue de leur industrialisation. Pour étudier expérimentalement ces mécanismes, une approche analytique par implantation ionique est utilisée dans cette étude, permettant de contrôler différents paramètres de synthèse de ces précipités comme la température et leur concentration. Ce projet a permis de démontrer la faisabilité de cette méthode et d'étudier le comportement d'alliages modèles (à base d'oxyde d'aluminium) sous recuit thermique. Des alliages Fe-10Cr de haute pureté ont été implantés avec des ions Al et O à température ambiante. Les observations de microscopie électronique en transmission ont montré que des nano-oxydes apparaissent dans la matrice de Fe-10Cr dès l'implantation à température ambiante, sans recuit subséquent. Les défauts créés lors de l'implantation ionique sont à l'origine de la mobilité des éléments introduits, permettant la nucléation de ces nanoparticules, de quelques nm de diamètre. Ces nanoparticules sont composées d'aluminium et d'oxygène, et également de chrome. Les examens en haute résolution montrent que leur structure cristallographique correspond à celle d'un composé hors équilibre de l'oxyde d'aluminium (de type γ-Al₂O₃). Les traitements thermiques effectués après implantation induisent une croissance de la taille de ces nano-oxydes, et un changement de phase qui tend vers la structure d'équilibre (de type α-Al₂O₃). Ces résultats sur des alliages modèles s'appliquent entièrement aux matériaux industriels : en effet l'implantation ionique reproduit les conditions du broyage, et les traitements thermiques sont à des températures équivalentes à celles des traitements d'élaboration thermo-mécaniques. Un mécanisme de la précipitation de nano-oxydes dispersés dans des alliages ODS est proposé dans ce manuscrit
ODS (Oxide Dispersed Strengthened) steels, which are reinforced with metal dispersions of nano-oxides (based on Y, Ti and O elements), are promising materials for future nuclear reactors. The detailed understanding of the mechanisms involved in the precipitation of these nano-oxides would improve manufacturing and mechanical properties of these ODS steels, with a strong economic impact for their industrialization. To experimentally study these mechanisms, an analytical approach by ion implantation is used, to control various parameters of synthesis of these precipitates as the temperature and concentration. This study demonstrated the feasibility of this method and concerned the behaviour of alloys models (based on aluminium oxide) under thermal annealing. High purity Fe-10Cr alloys were implanted with Al and O ions at room temperature. Transmission electron microscopy observations showed that the nano-oxides appear in the Fe-10Cr matrix upon ion implantation at room temperature without subsequent annealing. The mobility of implanted elements is caused by the defects created during ion implantation, allowing the nucleation of these nanoparticles, of a few nm in diameter. These nanoparticles are composed of aluminium and oxygen, and also chromium. The high-resolution experiments show that their crystallographic structure is that of a non-equilibrium compound of aluminium oxide (cubic γ-Al₂O₃ type). The heat treatment performed after implantation induces the growth of the nano-sized oxides, and a phase change that tends to balance to the equilibrium structure (hexagonal α-Al₂O₃ type). These results on model alloys are fully applicable to industrial materials: indeed ion implantation reproduces the conditions of milling and heat treatments are at equivalent temperatures to those of thermo-mechanical treatments. A mechanism involving the precipitation of nano-oxide dispersed in ODS alloys is proposed in this manuscript based on the obtained experimental results, and the existing literature

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43

Roshchupkina, Olga [Verfasser], Jürgen [Akademischer Betreuer] Fassbender y V. [Akademischer Betreuer] Holy. "Ion beam induced structural modifications in nano-crystalline permalloy thin films / Olga Roshchupkina. Gutachter: Jürgen Fassbender ; V. Holy. Betreuer: Jürgen Fassbender". Dresden : Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://d-nb.info/1068152656/34.

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44

Sun, Xida. "Structured Silicon Macropore as Anode in Lithium Ion Batteries". Wright State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=wright1316470033.

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45

Patryarcha, Lukas [Verfasser]. "Experiments and simulations on the structural and electrical properties of nano- and microstructures on graphite surfaces produced by ion beam lithography / Lukas Patryarcha". Dortmund : Universitätsbibliothek Technische Universität Dortmund, 2011. http://d-nb.info/1018124373/34.

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46

Kaymak, Vural [Verfasser], Alexander [Akademischer Betreuer] Pukhov, Alexander [Gutachter] Pukhov, Carsten [Gutachter] Müller y Malte [Gutachter] Kaluza. "Ultrahigh energy density physics and ion acceleration in nano- and microstructures / Vural Kaymak ; Gutachter: Alexander Pukhov, Carsten Müller, Malte Kaluza ; Betreuer: Alexander Pukhov". Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2019. http://d-nb.info/1201881927/34.

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47

Kaymak, Vural [Verfasser], Alexander [Akademischer Betreuer] Pukhov, Alexander [Gutachter] Pukhov, Carsten [Gutachter] Müller y Malte [Gutachter] Kaluza. "Ultrahigh energy density physics and ion acceleration in nano- and microstructures / Vural Kaymak ; Gutachter: Alexander Pukhov, Carsten Müller, Malte Kaluza ; Betreuer: Alexander Pukhov". Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2020. http://d-nb.info/1205544151/34.

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48

Mokhtarzadeh, Mahsa. "Nano-patterning by ion bombardment". Thesis, 2018. https://hdl.handle.net/2144/34769.

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The bombardment of surfaces by ions can lead to the spontaneous formation of nano-structures. Depending on the irradiation conditions, smoothening or roughening mechanisms can be the leading order in pattern formation which can result in the creation of dots, ripples or ultra-smoothening effects. Because ion bombardment is already ubiquitous in industrial settings, and is relatively inexpensive compared to other surface processing techniques, self-organized patterning by ion bombardment could enable a simple, economical means of inducing well-defined nanoscale structures in a variety of settings. Understanding the fundamental behavior of surfaces during ion bombardment is therefore a vital goal; however, a complete understanding of physical processes governing surface pattern formation has not been reached yet. In order to address this issue, my thesis research has utilized three primary approaches. First, I have done real-time non-coherent X-ray scattering experiments at Cornell High Energy Synchrotron Source (CHESS) for studying kinetics of structure formation of Silicon undergoing Ar⁺ bombardment over a range of wavenumbers 4-5 times larger than has previously been obtained. From our data, we were able to extract values of the angle-dependent thickness of the amorphous layer that forms under ion bombardment, the ion-enhanced fluidity within that film, the magnitude of the stress being generated by the ion beam, and the strength of prompt atomic displacement mechanisms. Second, to further deepen our knowledge of surface dynamics, I have performed coherent X-ray studies of Ar⁺ bombardment of SiO₂ at the Advanced Photon Source (APS) for investigating the dynamics more profoundly than can be done with traditional time-resolved experiments. When using a focused ion beam, an inhomogeneous ripple motion was generated, this phenomenon reflected as an oscillatory behavior in the two-time and corresponding g₂(t) correlation functions. By fitting the oscillations in the g₂(t) correlation function, we have determined the surface ripple velocity on SiO₂ driven by Ar⁺ sputter erosion. Finally, to support the results of coherent X-ray experiments, simulations of growth models such as linear Kuramoto-Sivashinsky (KS) and Kardar-Parisi-Zhang (KPZ) have been carried out in order to compare the simulated temporal correlation functions of the scattered intensity with those obtained from the coherent x-ray scattering experiments.

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49

Wu, Ting-Hsien y 吳侹賢. "Research Sterilization Effect of Nano Silver Ion". Thesis, 2009. http://ndltd.ncl.edu.tw/handle/81614527895882733120.

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碩士
吳鳳技術學院
光機電暨材料研究所
97
Kaolin contains essential zeolite components SiO2 and Al2O3. This study synthesized A-type zeolite by using kaolin as a raw material. The kaolin was activated by transforming it from crystalline to amorphous state, then the denatured kaolin was added to an alkaline solution, transformed it to A-type zeolite. The ion exchange method was used for preparing Ag-carrying zeolite antimicrobial. A plate count method was used for the antibacterial test after the antimicrobial has been added to an incubation solution and incubated for 72hr. The antibacterial rate show that 3 % of antimicrobial is enough to kill almost all the bacteria.

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50

Huang, Zih-Ying y 黃姿穎. "Ion Transport in Gel Electrolytes at the Nano- and Subnanoscales". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/64j2hr.

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