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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
301

Corrosion Study Of Interstitially Hardened SS 316L AND IN718 In Simulated Light Water Reactor Conditions

Niu, Wei January 2017 (has links)
No description available.
302

The Formation of Amorphous and Crystalline Damage in Metallic and Semiconducting Materials under Gallium Ion Irradiation

Presley, Michael 28 December 2016 (has links)
No description available.
303

Thermische Stabilität und Reaktion metallischer Multilagen / Thermal stability and reaction of metallic multilayers

Ene, Constantin Buzau 19 December 2007 (has links)
No description available.
304

Elastische Rückstoßatomspektrometrie leichter Elemente mit Subnanometer-Tiefenauflösung

Kosmata, Marcel 29 February 2012 (has links) (PDF)
In der vorliegenden Arbeit wird erstmals das QQDS-Magnetspektrometer für die höchstauflösende Ionenstrahlanalytik leichter Elemente am Helmholtz-Zentrum Dresden-Rossendorf umfassend vorgestellt. Zusätzlich werden sowohl alle auf die Analytik Einfluss nehmenden Parameter untersucht als auch Methoden und Modelle vorgestellt, wie deren Einfluss vermieden oder rechnerisch kompensiert werden kann. Die Schwerpunkte dieser Arbeit gliedern sich in fünf Bereiche. Der Erste ist der Aufbau und die Inbetriebnahme des QQDS-Magnetspektrometers, der zugehörige Streukammer mit allen Peripheriegeräten und des eigens für die höchstauflösende elastische Rückstoßanalyse entwickelten Detektors. Sowohl das umgebaute Spektrometer als auch der im Rahmen dieser Arbeit gebaute Detektor wurden speziell an experimentelle Bedingungen für die höchstauflösende Ionenstrahlanalytik leichter Elemente angepasst und erstmalig auf einen routinemäßigen Einsatz hin getestet. Der Detektor besteht aus zwei Komponenten. Zum einen befindet sich am hinteren Ende des Detektors eine Bragg-Ionisationskammer, die zur Teilchenidentifikation genutzt wird. Zum anderen dient ein Proportionalzähler, der eine Hochwiderstandsanode besitzt und direkt hinter dem Eintrittsfenster montiert ist, zur Teilchenpositionsbestimmung im Detektor. Die folgenden zwei Schwerpunkte beinhalten grundlegende Untersuchungen zur Ionen-Festkörper-Wechselwirkung. Durch die Verwendung eines Magnetspektrometers ist die Messung der Ladungszustandsverteilung der herausgestreuten Teilchen direkt nach einem binären Stoß sowohl möglich als auch für die Analyse notwendig. Aus diesem Grund werden zum einen die Ladungszustände gemessen und zum anderen mit existierenden Modellen verglichen. Außerdem wird ein eigens entwickeltes Modell vorgestellt und erstmals im Rahmen dieser Arbeit angewendet, welches den ladungszustandsabhängigen Energieverlust bei der Tiefenprofilierung berücksichtigt. Es wird gezeigt, dass ohne die Anwendung dieses Modells die Tiefenprofile nicht mit den quantitativen Messungen mittels konventioneller Ionenstrahlanalytikmethoden und mit der Dickenmessung mittels Transmissionselektronenmikroskopie übereinstimmen, und damit falsche Werte liefern würden. Der zweite für die Thematik wesentliche Aspekt der Ionen-Festkörper-Wechselwirkung, sind die Probenschäden und -modifikationen, die während einer Schwerionen-bestrahlung auftreten. Dabei wird gezeigt, dass bei den hier verwendeten Energien sowohl elektronisches Sputtern als auch elektronisch verursachtes Grenzflächendurchmischen eintreten. Das elektronische Sputtern kann durch geeignete Strahlparameter für die meisten Proben ausreichend minimiert werden. Dagegen ist der Einfluss der Grenzflächendurchmischung meist signifikant, so dass dieser analysiert und in der Auswertung berücksichtigt werden muss. Schlussfolgernd aus diesen Untersuchungen ergibt sich für die höchstauflösende Ionenstrahlanalytik leichter Elemente am Rossendorfer 5-MV Tandembeschleuniger, dass die geeignetsten Primärionen Chlor mit einer Energie von 20 MeV sind. In Einzelfällen, wie zum Beispiel der Analyse von Bor, muss die Energie jedoch auf 6,5 MeV reduziert werden, um das elektronische Sputtern bei der notwendigen Fluenz unterhalb der Nachweisgrenze zu halten. Der vierte Schwerpunkt ist die Untersuchung von sowohl qualitativen als auch quantitativen Einflüssen bestimmter Probeneigenschaften, wie beispielsweise Oberflächenrauheit, auf die Form des gemessenen Energiespektrums beziehungsweise auf das analysierte Tiefenprofil. Die Kenntnis der Rauheit einer Probe an der Oberfläche und an den Grenzflächen ist für die Analytik unabdingbar. Als Resultat der genannten Betrachtungen werden die Einflüsse von Probeneigenschaften und Ionen-Festkörper-Wechselwirkungen auf die Energie- beziehungsweise Tiefenauflösung des Gesamtsystems beschrieben, berechnet und mit der konventionellen Ionenstrahlanalytik verglichen. Die Möglichkeiten der höchstauflösenden Ionenstrahlanalytik werden zudem mit den von anderen Gruppen veröffentlichten Komplementärmethoden gegenübergestellt. Der fünfte und letzte Schwerpunkt ist die Analytik leichter Elemente in ultradünnen Schichten unter Berücksichtigung aller in dieser Arbeit vorgestellten Modelle, wie die Reduzierung des Einflusses von Strahlschäden oder die Quantifizierung der Elemente im dynamischen Ladungszustandsnichtgleichgewicht. Es wird die Tiefenprofilierung von Mehrschichtsystemen, bestehend aus SiO2-Si3N4Ox-SiO2 auf Silizium, von Ultra-Shallow-Junction Bor-Implantationsprofilen und von ultradünnen Oxidschichten, wie zum Beispiel High-k-Materialien, demonstriert. / In this thesis the QQDS magnetic spectrometer that is used for high resolution ion beam analysis (IBA) of light elements at the Helmholtz-Zentrum Dresden-Rossendorf is presented for the first time. In addition all parameters are investigated that influence the analysis. Methods and models are presented with which the effects can be minimised or calculated. There are five focal points of this thesis. The first point is the construction and commissioning of the QQDS magnetic spectrometer, the corresponding scattering chamber with all the peripherals and the detector, which is specially developed for high resolution elastic recoil detection. Both the reconstructed spectrometer and the detector were adapted to the specific experimental conditions needed for high-resolution Ion beam analysis of light elements and tested for routine practice. The detector consists of two compo-nents. At the back end of the detector a Bragg ionization chamber is mounted, which is used for the particle identification. At the front end, directly behind the entrance window a proportional counter is mounted. This proportional counter includes a high-resistance anode. Thus, the position of the particles is determined in the detector. The following two points concern fundamental studies of ion-solid interaction. By using a magnetic spectrometer the charge state distribution of the particles scattered from the sample after a binary collision is both possible and necessary for the analysis. For this reason the charge states are measured and compared with existing models. In addition, a model is developed that takes into account the charge state dependent energy loss. It is shown that without the application of this model the depth profiles do not correspond with the quantitative measurements by conventional IBA methods and with the thickness obtained by transmission electron microscopy. The second fundamental ion-solid interaction is the damage and the modification of the sample that occurs during heavy ion irradiation. It is shown that the used energies occur both electronic sputtering and electronically induced interface mixing. Electronic sputtering is minimised by using optimised beam parameters. For most samples the effect is below the detection limit for a fluence sufficient for the analysis. However, the influence of interface mixing is so strong that it has to be included in the analysis of the layers of the depth profiles. It is concluded from these studies that at the Rossendorf 5 MV tandem accelerator chlorine ions with an energy of 20 MeV deliver the best results. In some cases, such as the analysis of boron, the energy must be reduced to 6.5 MeV in order to retain the electronic sputtering below the detection limit. The fourth focus is the study of the influence of specific sample properties, such as surface roughness, on the shape of a measured energy spectra and respectively on the analysed depth profile. It is shown that knowledge of the roughness of a sample at the surface and at the interfaces for the analysis is needed. In addition, the contribution parameters limiting the depth resolution are calculated and compared with the conventional ion beam analysis. Finally, a comparison is made between the high-resolution ion beam analysis and complementary methods published by other research groups. The fifth and last focus is the analysis of light elements in ultra thin layers. All models presented in this thesis to reduce the influence of beam damage are taken into account. The dynamic non-equilibrium charge state is also included for the quantification of elements. Depth profiling of multilayer systems is demonstrated for systems consisting of SiO2-Si3N4Ox-SiO2 on silicon, boron implantation profiles for ultra shallow junctions and ultra thin oxide layers, such as used as high-k materials.
305

Elastische Rückstoßatomspektrometrie leichter Elemente mit Subnanometer-Tiefenauflösung

Kosmata, Marcel 21 December 2011 (has links)
In der vorliegenden Arbeit wird erstmals das QQDS-Magnetspektrometer für die höchstauflösende Ionenstrahlanalytik leichter Elemente am Helmholtz-Zentrum Dresden-Rossendorf umfassend vorgestellt. Zusätzlich werden sowohl alle auf die Analytik Einfluss nehmenden Parameter untersucht als auch Methoden und Modelle vorgestellt, wie deren Einfluss vermieden oder rechnerisch kompensiert werden kann. Die Schwerpunkte dieser Arbeit gliedern sich in fünf Bereiche. Der Erste ist der Aufbau und die Inbetriebnahme des QQDS-Magnetspektrometers, der zugehörige Streukammer mit allen Peripheriegeräten und des eigens für die höchstauflösende elastische Rückstoßanalyse entwickelten Detektors. Sowohl das umgebaute Spektrometer als auch der im Rahmen dieser Arbeit gebaute Detektor wurden speziell an experimentelle Bedingungen für die höchstauflösende Ionenstrahlanalytik leichter Elemente angepasst und erstmalig auf einen routinemäßigen Einsatz hin getestet. Der Detektor besteht aus zwei Komponenten. Zum einen befindet sich am hinteren Ende des Detektors eine Bragg-Ionisationskammer, die zur Teilchenidentifikation genutzt wird. Zum anderen dient ein Proportionalzähler, der eine Hochwiderstandsanode besitzt und direkt hinter dem Eintrittsfenster montiert ist, zur Teilchenpositionsbestimmung im Detektor. Die folgenden zwei Schwerpunkte beinhalten grundlegende Untersuchungen zur Ionen-Festkörper-Wechselwirkung. Durch die Verwendung eines Magnetspektrometers ist die Messung der Ladungszustandsverteilung der herausgestreuten Teilchen direkt nach einem binären Stoß sowohl möglich als auch für die Analyse notwendig. Aus diesem Grund werden zum einen die Ladungszustände gemessen und zum anderen mit existierenden Modellen verglichen. Außerdem wird ein eigens entwickeltes Modell vorgestellt und erstmals im Rahmen dieser Arbeit angewendet, welches den ladungszustandsabhängigen Energieverlust bei der Tiefenprofilierung berücksichtigt. Es wird gezeigt, dass ohne die Anwendung dieses Modells die Tiefenprofile nicht mit den quantitativen Messungen mittels konventioneller Ionenstrahlanalytikmethoden und mit der Dickenmessung mittels Transmissionselektronenmikroskopie übereinstimmen, und damit falsche Werte liefern würden. Der zweite für die Thematik wesentliche Aspekt der Ionen-Festkörper-Wechselwirkung, sind die Probenschäden und -modifikationen, die während einer Schwerionen-bestrahlung auftreten. Dabei wird gezeigt, dass bei den hier verwendeten Energien sowohl elektronisches Sputtern als auch elektronisch verursachtes Grenzflächendurchmischen eintreten. Das elektronische Sputtern kann durch geeignete Strahlparameter für die meisten Proben ausreichend minimiert werden. Dagegen ist der Einfluss der Grenzflächendurchmischung meist signifikant, so dass dieser analysiert und in der Auswertung berücksichtigt werden muss. Schlussfolgernd aus diesen Untersuchungen ergibt sich für die höchstauflösende Ionenstrahlanalytik leichter Elemente am Rossendorfer 5-MV Tandembeschleuniger, dass die geeignetsten Primärionen Chlor mit einer Energie von 20 MeV sind. In Einzelfällen, wie zum Beispiel der Analyse von Bor, muss die Energie jedoch auf 6,5 MeV reduziert werden, um das elektronische Sputtern bei der notwendigen Fluenz unterhalb der Nachweisgrenze zu halten. Der vierte Schwerpunkt ist die Untersuchung von sowohl qualitativen als auch quantitativen Einflüssen bestimmter Probeneigenschaften, wie beispielsweise Oberflächenrauheit, auf die Form des gemessenen Energiespektrums beziehungsweise auf das analysierte Tiefenprofil. Die Kenntnis der Rauheit einer Probe an der Oberfläche und an den Grenzflächen ist für die Analytik unabdingbar. Als Resultat der genannten Betrachtungen werden die Einflüsse von Probeneigenschaften und Ionen-Festkörper-Wechselwirkungen auf die Energie- beziehungsweise Tiefenauflösung des Gesamtsystems beschrieben, berechnet und mit der konventionellen Ionenstrahlanalytik verglichen. Die Möglichkeiten der höchstauflösenden Ionenstrahlanalytik werden zudem mit den von anderen Gruppen veröffentlichten Komplementärmethoden gegenübergestellt. Der fünfte und letzte Schwerpunkt ist die Analytik leichter Elemente in ultradünnen Schichten unter Berücksichtigung aller in dieser Arbeit vorgestellten Modelle, wie die Reduzierung des Einflusses von Strahlschäden oder die Quantifizierung der Elemente im dynamischen Ladungszustandsnichtgleichgewicht. Es wird die Tiefenprofilierung von Mehrschichtsystemen, bestehend aus SiO2-Si3N4Ox-SiO2 auf Silizium, von Ultra-Shallow-Junction Bor-Implantationsprofilen und von ultradünnen Oxidschichten, wie zum Beispiel High-k-Materialien, demonstriert. / In this thesis the QQDS magnetic spectrometer that is used for high resolution ion beam analysis (IBA) of light elements at the Helmholtz-Zentrum Dresden-Rossendorf is presented for the first time. In addition all parameters are investigated that influence the analysis. Methods and models are presented with which the effects can be minimised or calculated. There are five focal points of this thesis. The first point is the construction and commissioning of the QQDS magnetic spectrometer, the corresponding scattering chamber with all the peripherals and the detector, which is specially developed for high resolution elastic recoil detection. Both the reconstructed spectrometer and the detector were adapted to the specific experimental conditions needed for high-resolution Ion beam analysis of light elements and tested for routine practice. The detector consists of two compo-nents. At the back end of the detector a Bragg ionization chamber is mounted, which is used for the particle identification. At the front end, directly behind the entrance window a proportional counter is mounted. This proportional counter includes a high-resistance anode. Thus, the position of the particles is determined in the detector. The following two points concern fundamental studies of ion-solid interaction. By using a magnetic spectrometer the charge state distribution of the particles scattered from the sample after a binary collision is both possible and necessary for the analysis. For this reason the charge states are measured and compared with existing models. In addition, a model is developed that takes into account the charge state dependent energy loss. It is shown that without the application of this model the depth profiles do not correspond with the quantitative measurements by conventional IBA methods and with the thickness obtained by transmission electron microscopy. The second fundamental ion-solid interaction is the damage and the modification of the sample that occurs during heavy ion irradiation. It is shown that the used energies occur both electronic sputtering and electronically induced interface mixing. Electronic sputtering is minimised by using optimised beam parameters. For most samples the effect is below the detection limit for a fluence sufficient for the analysis. However, the influence of interface mixing is so strong that it has to be included in the analysis of the layers of the depth profiles. It is concluded from these studies that at the Rossendorf 5 MV tandem accelerator chlorine ions with an energy of 20 MeV deliver the best results. In some cases, such as the analysis of boron, the energy must be reduced to 6.5 MeV in order to retain the electronic sputtering below the detection limit. The fourth focus is the study of the influence of specific sample properties, such as surface roughness, on the shape of a measured energy spectra and respectively on the analysed depth profile. It is shown that knowledge of the roughness of a sample at the surface and at the interfaces for the analysis is needed. In addition, the contribution parameters limiting the depth resolution are calculated and compared with the conventional ion beam analysis. Finally, a comparison is made between the high-resolution ion beam analysis and complementary methods published by other research groups. The fifth and last focus is the analysis of light elements in ultra thin layers. All models presented in this thesis to reduce the influence of beam damage are taken into account. The dynamic non-equilibrium charge state is also included for the quantification of elements. Depth profiling of multilayer systems is demonstrated for systems consisting of SiO2-Si3N4Ox-SiO2 on silicon, boron implantation profiles for ultra shallow junctions and ultra thin oxide layers, such as used as high-k materials.
306

Korngrenzsegregation in Silber-Nickel und Kupfer-Wismut Legierungen / Grain Boundary Segregation in Silver-Nickel and Copper-Bismuth Alloys

Wolde-Giorgis, Daniel 25 August 2005 (has links)
No description available.
307

Software architecture for capturing clinical information in hadron therapy and the design of an ion beam for radiobiology

Abler, Daniel Jakob Silvester January 2013 (has links)
Hadron Therapy (HT) exploits properties of ion radiation to gain therapeutic advantages over existing photon-based forms of external radiation therapy. However, its relative superiority and cost-effectiveness have not been proven for all clinical situations. Establishing a robust evidence base for the development of best treatment practices is one of the major challenges for the field. This thesis investigates two research infrastructures for building this essential evidence. First, the thesis develops main components of a metadata-driven software architecture for the collection of clinical information and its analysis. This architecture acknowledges the diversity in the domain and supports data interoperability by sharing information models. Their compliance to common metamodels guarantees that primary data and analysis results can be interpreted outside of the immediate production context. This is a fundamental necessity for all aspects of the evidence creation process. A metamodel of data capture forms is developed with unique properties to support data collection and documentation in this architecture. The architecture's potential to support complex analysis processes is demonstrated with the help of a novel metamodel for Markov model based simulations, as used for the synthesis of evidence in health-economic assessments. The application of both metamodels is illustrated on the example of HT. Since the biological effect of particle radiation is a major source of uncertainty in HT, in its second part, this thesis undertakes first investigations towards a new research facility for bio-medical experiments with ion beams. It examines the feasibility of upgrading LEIR, an existing accelerator at the European Organisation for Nuclear Research (CERN), with a new slow extraction and investigates transport of the extracted beam to future experiments. Possible configurations for the slow-resonant extraction process are identified, and designs for horizontal and vertical beam transport lines developed. The results of these studies indicate future research directions towards a new ion beam facility for biomedical research.
308

Integration and Fabrication Techniques for 3D Micro- and Nanodevices

Fischer, Andreas C. January 2012 (has links)
The development of micro and nano-electromechanical systems (MEMS and NEMS) with entirely new or improved functionalities is typically based on novel or improved designs, materials and fabrication methods. However, today’s micro- and nano-fabrication is restrained by manufacturing paradigms that have been established by the integrated circuit (IC) industry over the past few decades. The exclusive use of IC manufacturing technologies leads to limited material choices, limited design flexibility and consequently to sub-optimal MEMS and NEMS devices. The work presented in this thesis breaks new ground with a multitude of novel approaches for the integration of non-standard materials that enable the fabrication of 3D micro and nanoelectromechanical systems. The objective of this thesis is to highlight methods that make use of non-standard materials with superior characteristics or methods that use standard materials and fabrication techniques in a novel context. The overall goal is to propose suitable and cost-efficient fabrication and integration methods, which can easily be made available to the industry. The first part of the thesis deals with the integration of bulk wire materials. A novel approach for the integration of at least partly ferromagnetic bulk wire materials has been implemented for the fabrication of high aspect ratio through silicon vias. Standard wire bonding technology, a very mature back-end technology, has been adapted for yet another through silicon via fabrication method and applications including liquid and vacuum packaging as well as microactuators based on shape memory alloy wires. As this thesis reveals, wire bonding, as a versatile and highly efficient technology, can be utilized for applications far beyond traditional interconnections in electronics packaging. The second part presents two approaches for the 3D heterogeneous integration based on layer transfer. Highly efficient monocrystalline silicon/ germanium is integrated on wafer-level for the fabrication of uncooled thermal image sensors and monolayer-graphene is integrated on chip-level for the use in diaphragm-based pressure sensors. The last part introduces a novel additive fabrication method for layer-bylayer printing of 3D silicon micro- and nano-structures. This method combines existing technologies, including focused ion beam implantation and chemical vapor deposition of silicon, in order to establish a high-resolution fabrication process that is related to popular 3D printing techniques. / <p>QC 20121207</p>
309

Microstructural characterisation of novel nitride nanostructures using electron microscopy

Severs, John January 2014 (has links)
Novel semiconductor nanostructures possess a range of notable properties that have the potential to be harnessed in the next generation of optical devices. Electron microscopy is uniquely suited to characterising the complex microstructure, the results of which may be related to the growth conditions and optical properties. This thesis investigates three such novel materials: (1) GaN/InGaN core/shell nanowires, (2) n-GaN/InGaN/p-GaN core/multi-shell microrods and (3) Zn<sub>3</sub>N<sub>2</sub> nanoparticles, all of which were grown at Sharp Laboratories of Europe. GaN nanowires were grown by a Ni-catalysed VLS process and were characterised by various techniques before and after InGaN shells were deposited by MOCVD. The majority of the core wires were found to have the expected wurtzite structure and completely defect free – reflected in the strong strain-free photoluminescence peak –with a- and m- axis orientations identified with shadow imaging. A small component, <5%, were found to have the cubic zinc-blende phase and a high density of planar faults running the length of the wires. The deposited shells were highly polycrystalline, partially attributed to a layer of silicon at the core shell interface identified through FIB lift-out of cross section samples, and accordingly the PL was very broad likely due to recombination at defects and grain boundaries. A high throughput method of identifying the core size indirectly via the catalyst particle EDX signal is described which may be used to link the shell microstructure to core size in further studies. An n-GaN/InGaN/p-GaN shell structure was deposited by MOCVD on the side walls of microrods etched from c-axis GaN film on sapphire, which offers the possibility of achieving non-polar junctions without the issues due to non-uniformity found in nanowires. Threading dislocations within the core related to the initial growth on sapphire were shown to be confined to this region, therefore avoiding any harmful effect on the junction microstructure. The shell defect density showed a surprising relationship to core size with the smaller diameter rods having a high density of unusual 'flag' defects in the junction region whereas the larger diameter sample shells appeared largely defect free, suggesting the geometry of the etched core has an impact on the strain in the shell layers. The structure of unusual 'flag' defects in the m-plane junctions was characterised via diffraction contrast TEM, weak beam and atomic resolution ADF STEM and were shown to consist of a basal plane stacking faults meeting a perfect or partial dislocation loop on a pyramidal plane, the latter likely gliding in to resolve residual strain due to the fault formed during growth. Zn<sub>3</sub>N<sub>2</sub> has the required bandgap energy to be utilised as a phosphor with the additional advantage over conventional materials of its constituent elements not being toxic or scarce. The first successful synthesis of Zn<sub>3</sub>N<sub>2</sub> nanoparticles appropriate to this application was confirmed via SAD, EDX and HRTEM, with software developed to fit experimental polycrystalline diffraction patterns to simulated components suggesting a maximum Zn<sub>3</sub>N<sub>2</sub> composition of ~30%. There was an apparent decrease in crystallinity with decreasing particle size evidenced in radial distribution function studies with the smallest particles appearing completely amorphous in 80kV HRTEM images. A rapid change in the particles under the electron beam was observed, characterised by growth of large grains of Zn<sub>3</sub>N<sub>2</sub> and ZnO which increased with increasing acceleration voltage suggesting knock-on effects driving the change. PL data was consistent with the bandgap of Zn<sub>3</sub>N<sub>2</sub> blue shifted from 1.1eV to around 1.8eV, confirming the potential of the material for application as a phosphor.
310

Estudos de técnicas de feixes iônicos para a quantificação do elemento químico boro / Study of boron quantification using ion beam analysis techniques.

Moro, Marcos Vinicius 16 May 2013 (has links)
Neste trabalho, estudamos e aplicamos técnicas analíticas com feixes iônicos para a identificação e quantificação do elemento químico Boro em amostras de Boro depositado sobre Níquel 11B/Ni, sobre Silício B/Si e em amostras de Silício Grau Metalúrgico - SiGM. Estas últimas foram fornecidas pelo grupo de metalurgia do Instituto de Pesquisas Tecnológicas (IPT). Especificamente, as seguintes técnicas analíticas foram utilizadas: Nuclear Reaction Analysis - NRA, Elastic Recoil Detection Analysis - ERDA e Secondary Ion Mass Spectrometry - SIMS. Nas amostras de B/Ni e B/Si, as concentrações foram obtidas com medidas de NRA, ERDA e SIMS. Também foi abordado quais dentre essas três técnicas apresentam menor limite de deteção e menor incerteza para a quantificação de Boro. Usando a reação nuclear 11B(p,a0)8Be, foi possível calcular a sua seção de choque diferencial para ângulo de espalhamento theta=170, cujo resultado, para este ângulo específico, é inédito na literatura. As amostras de SiGM foram analisadas com a técnica SIMS e comparadas com medidas de Inductively Coupled Plasma - ICP realizadas pelo grupo do IPT. Uma vez que técnicas nucleares podem ser consideradas absolutas, concluímos que as medidas de ICP apresentaram dados compatíveis com as medidas SIMS, e que o grupo de metalurgia do IPT está medindo as concentrações de Boro em suas amostras de SiGM corretamente por meio de ICP. Uma reta de calibração entre medidas SIMSxICP foi construída, que poderá servir como um guia para futuras quantificações de Boro com ICP feitas pelo grupo de metalurgia do IPT. / In this work we investigated the use of analytical techniques based on ion beams in the quantification of Boron in many kinds of samples. Specifically, we applied techniques such Nuclear Reaction Analysis (NRA), Elastic Recoil Detection Analysis (ERDA) and Secondary Ion Mass Spectrometry (SIMS) to 11B/Ni and B/Si samples to measure the boron concentration. We also discuss and show what technique has a better detection limit and lower uncertainty. For the first time in the literature, we obtained the cross section for the $^{11}B(p,\\alpha_0){^8}Be$ nuclear reaction in the energy range from 1.6 up to 2.0 MeV in theta = 170 scattering angle. The SIMS technique was applied to analise samples of metallurgical grade silicon (SiGM) from Metallurgy Group of Instituto de Pesquisas Tecnologicas (IPT) to check the Inductively Coupled Plasma (ICP) measurements carried out by the IPT. Moreover, it was possible to build a calibration curve between SIMS and ICP measurements, that can be used to help of Metallurgy Group with futures ICP\'s measurements.

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