Дисертації: "Ion beam induced luminescence"

1

Brooks, Robert. "Ion beam induced luminescence of materials." Thesis, University of Sussex, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391861.

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2

Haycock, P. W. "Ion beam induced luminescence and polarisation reversal in ferroelectric crystals." Thesis, University of Sussex, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373155.

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3

Dubner, Andrew D. (Andrew David). "Mechanism of ion beam induced deposition." Thesis, Massachusetts Institute of Technology, 1990. http://hdl.handle.net/1721.1/13637.

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4

Della, Ratta Anthony D. (Anthony David). "Focused ion beam induced deposition of copper." Thesis, Massachusetts Institute of Technology, 1993. http://hdl.handle.net/1721.1/12418.

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5

Sukirno. "Ion beam induced interface motion and impurity relocation." Thesis, University of Salford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293846.

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6

Funatsu, Jun. "Laser-assisted focused-ion-beam-induced deposition of copper." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/32617.

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7

Zhou, Hua. "Ion Beam Erosion-Induced Self-Organized Nanostructures On Sapphire." ScholarWorks @ UVM, 2007. http://scholarworks.uvm.edu/graddis/246.

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Ion beam erosion of solid surfaces is known to produce a variety of surface morpholo- gies, such as pits, mounds or crests. Very often self-organized patterns composed of highly correlated arrays of dots or ripples at sub-micrometer and nanometer length scale could be obtained. Ion beam erosion patterning have demonstrated the poten- tial to tailor related surface properties for optoelectronic and spintronic applications, such as modulated photoemission induced by quantum con¯nement of nanodots and magnetic anisotropy induced by nanoripples. On the other hand, one considerable practical importance and e®ect of ion beam erosion is that of surface smoothing of nanometer features, during etching or ¯lm deposition coincident with energetic species. In my dissertation, systematic investigations of ripple formation and smooth- ing during low energy Ar+ ion erosion of sapphire surfaces using synchrotron grazing incidence small angle x-ray scattering and atomic force microscopy are performed. It is found in the pattern formation that the wavelength of ripples can be varied over a remarkably wide range by changing the ion incidence angle. The ion induced viscous °ow smoothing mechanism explains the general trends of the ripple wavelength at low temperature and incidence angles larger than 30±. The behavior at high temper- atures suggests relaxation by surface di®usion. However, strong smoothing is inferred from the observed ripple wavelength near normal incidence, which is not consistent with either surface di®usion or viscous °ow relaxation. Furthermore, a real-time x- ray scattering experiment is presented showing that ion smoothing of a pre-patterned surface near normal incidence is consistent with the e®ect of a collision-induced lat- eral current. Quantitative agreement is obtained using ion-collision simulations to compute the magnitude of the surface current. The results lead to predictions for the surface morphology phase diagram as a function of ion beam energy and incidence angle that substantially agree with experimental observations. The ion-induced lat- eral current smoothing model is applicable to many surfaces that become amorphous but maintain the stoichiometry of bulk materials during ion bombardment.

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8

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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9

Müller, Georg Alexander. "Ion-beam induced changes of magnetic and structural properties in thin Fe films." [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=971021570.

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10

Erola, Marja. "Ion beam and annealing induced effects in solid materials detected by nuclear methods." Hki : Societas scientiarum Fennica, 1988. http://catalog.hathitrust.org/api/volumes/oclc/58508563.html.

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11

Théberge, Roger. "An investigation of the beam-induced dehalogenation process in liquid secondary ion mass spectrometry." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq26743.pdf.

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12

Zmeck, Markus [Verfasser]. "Transient Ion Beam Induced Charge/Currents Microscopy on High Power Semiconductor Devices / Markus Zmeck." Aachen : Shaker, 2004. http://d-nb.info/1172613389/34.

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13

Coutee, Kyle L. "The Formation of Electrets by Ion Beam Induced Defects for Application in MEMS Devices." Thesis, University of Louisiana at Lafayette, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=10842266.

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A novel electret fabrication method has been explored using a 1.7 MV Pelletron accelerator. Also, a vibrating Kelvin probe was designed and constructed for the measurement of surface potentials. The electret formation method involved using proton beams of 2 MeV energy to both partially and completely penetrate dielectric samples with metallized back plates to create defect-induced surface potentials. These potentials would likely be more resilient than those of electrets fabricated by current popular methods because the effective charge would be deposited much deeper into the material. The potentials were monitored with a custom built Kelvin probe system. This method was worth exploring as there is currently a need for more resilient electrets in the design of energy efficient micro-electro-mechanical systems (MEMS). Currently, electrets cannot survive certain MEMS fabrication processes. Two types of samples were explored. The first were 150 um thick borosilicate glass slips with a sputter coated gold backing layer. The second were silicon substrates with a 300 nm thick SiO₂ layer deposited on one side and a silver backing layer on the other. The results of this thesis suggest that this charging method is inferior to other methods when applied to 150 um thick borosilicate glass. The borosilicate glass electrets were inferior both with respect to effective surface charge and effective surface charge retention. The effective surface charges attained with the SiO₂/Si samples were also lower than the lowest surface charges commonly achieved by other charging methods. The SiO₂/Si samples irradiated at fluences of 10¹¹ and 10¹³ ions/cm² showed decays comparable to those achieved by other methods as of this writing. This thesis is an overview of the design and construction of a Kelvin probe system, the aforementioned method, and a comparison of the results with the characteristics of electrets fabricated by other methods commonly used today.

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14

Gebel, Thoralf. "Nanocluster-rich SiO2 layers produced by ion beam synthesis: electrical and optoelectronic properties." Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-29449.

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The aim of this work was to find a correlation between the electrical, optical and microstructural properties of thin SiO2 layers containing group IV nanostructures produced by ion beam synthesis. The investigations were focused on two main topics: The electrical properties of Ge- and Si-rich oxide layers were studied in order to check their suitability for non-volatile memory applications. Secondly, photo- and electroluminescence (PL and EL) results of Ge-, Si/C- and Sn-rich SiO2 layers were compared to electrical properties to get a better understanding of the luminescence mechanism.

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15

Gebel, Thoralf. "Nanocluster-rich SiO2 layers produced by ion beam synthesis: electrical and optoelectronic properties." Forschungszentrum Rossendorf, 2002. https://hzdr.qucosa.de/id/qucosa%3A21773.

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The aim of this work was to find a correlation between the electrical, optical and microstructural properties of thin SiO2 layers containing group IV nanostructures produced by ion beam synthesis. The investigations were focused on two main topics: The electrical properties of Ge- and Si-rich oxide layers were studied in order to check their suitability for non-volatile memory applications. Secondly, photo- and electroluminescence (PL and EL) results of Ge-, Si/C- and Sn-rich SiO2 layers were compared to electrical properties to get a better understanding of the luminescence mechanism.

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16

Khalil, Ali Saied, and askhalil2004@yahoo com. "Heavy-Ion-Irradiation-Induced Disorder in Indium Phosphide and Selected Compounds." The Australian National University. Research School of Information Sciences and Engineering, 2007. http://thesis.anu.edu.au./public/adt-ANU20070716.140841.

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Indium phosphide (InP) is an important III-V compound, with a variety of applications, for example, in light emitting diodes (LED), InP based photonic crystals and in semiconductor lasers, heterojunction bipolar transistors in integrated circuit applications and in transistors for microwave and millimeter-wave systems. The optical and electrical properties of this compound can be further tailored by ion implantation or prospectively by swift heavy ion beams. ¶ Thus knowledge of ion-induced disorder in this material is of important fundamental and practical interest. However, the disorder produced during heavy ion irradiation and the subsequent damage accumulation and recovery in InP is far from being completely understood. In terms of the damage accumulation mechanisms, the conclusions drawn in the numerous studies performed have often been in conflict with one another. A factor contributing to the uncertainties associated with these conflicting results is a lack of information and direct observation of the building blocks leading to the ultimate damage created at high ion fluences as an amorphous layer. These building blocks formed at lower fluence regimes by single ion impacts can be directly observed as isolated disordered zones and ion tracks for low energy and swift heavy ion irradiation, respectively. ¶ The primary aim of this work has thus been to obtain a better understanding of the disorder in this material through direct observations and investigation of disorder produced by individual heavy ions in both energy regimes (i.e. elastic and inelastic energy deposition regimes) especially with low ion fluence irradiations. In this thesis the heavy ion induced disorder introduced by low energy Au ions (100 keV Au+) and high energy Au (200 MeV Au+16) ion irradiation in InP were investigated using Transmission Electron Microscopy (TEM), Rutherford Backscattering Spectrometry (RBS/C) and Atomic Force Microscopy (AFM). ¶ The accumulation of damage due to disordered zones and ion tracks is described and discussed for both low energy and swift ion irradiation respectively. ¶ The in-situ TEM annealing of disordered zones created by 100 keV Au+ ion irradiation shows that these zones are sensitive to electron beam irradiation and anneal under electron energies not sufficient to elastically displace lattice atoms, i.e. subthreshold energies for both constituent atoms In and P. ¶ Ion tracks due to swift heavy ion irradiation were observed in this material and the interesting track morphology was described and discussed. The surface nanotopographical changes due to increasing fluence of swift heavy ions were observed by AFM where the onset of large increase in surface roughness for fluences sufficient to cause complete surface amorphization was observed. ¶ In addition to InP, the principle material of this project, a limited amount of TEM observation work has been performed on several other important compounds (apatite and monazite) irradiated by 200 MeV Au+ ions for comparative purposes. Again the observed segmental morphology of ion tracks were shown and possible track formation scenario and structure were discussed and similarities were drawn to the previously observed C60 cluster ion tracks in CaF2 as more knowledge and data base exist about defect dynamics and formation in that material.

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17

Bevilacqua, Riccardo. "Neutron induced light-ion production from iron and bismuth at 175 MeV." Licentiate thesis, Uppsala University, Applied Nuclear Physics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-112162.

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Light-ions (protons, deuterons, tritons, ³He and α articles) production in the interaction of 175 MeV neutrons with iron and bismuth has been measured using the Medley setup at the The Svedberg Laboratory (TSL) in Uppsala. These measurements have been conducted in the frame of an international collaboration whose aim is to provide the scientific community with new nuclear data of interest for the development of Accelerator Driven Systems, in the range of 20 to 200 MeV. In this Licentiate Thesis I will present the background for the present experiment, the choice of the measured materials (iron and bismuth) and of the energy range. I will then give a short theoretical description of the involved nuclear reactions and of the model used to compare the experimental results. A description of the neutron facility at TSL and of Medley setup will follow. Monte Carlo simulations of the experimental setup have been performed and some results are here reported and discussed. I will present data reduction procedure and finally I will report preliminary double differential cross sections for production of hydrogen isotopes from iron and bismuth at several emission angles. Experimental data will be compared with model calculations with TALYS-1.0; these show better agreement for the production of protons, while seems to overestimate the experimental production of deuterons and tritons.

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18

Khanbabaee, Patekhour Behnam [Verfasser]. "Depth resolved investigation of ion beam induced pattern formation on silicon using X-ray methods / Behnam Khanbabaee Patekhour." Siegen : Universitätsbibliothek der Universität Siegen, 2014. http://d-nb.info/105311950X/34.

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19

Kupka, Katharina [Verfasser], Christina [Akademischer Betreuer] Trautmann, and Wolfgang [Akademischer Betreuer] Ensinger. "Intense heavy ion beam-induced effects in carbon-based stripper foils / Katharina Kupka. Betreuer: Christina Trautmann ; Wolfgang Ensinger." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2016. http://d-nb.info/1112333118/34.

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20

Prosvetov, Alexey [Verfasser], Christina [Akademischer Betreuer] Trautmann, and Wolfgang [Akademischer Betreuer] Ensinger. "Ion-beam induced modifications of structural and thermophysical properties of graphite materials. / Alexey Prosvetov ; Christina Trautmann, Wolfgang Ensinger." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2020. http://d-nb.info/1216627541/34.

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21

Sayler, A. Max. "Measurements of ultrashort intense laser-induced fragmentation of simple molecular ions." Diss., Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/2611.

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22

Bachiller, Perea Diana. "Ion-Irradiation-Induced Damage in Nuclear Materials : Case Study of a-SiO₂ and MgO." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS158/document.

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Un des plus grands défis de la Physique aujourd’hui est de créer une source d’énergie propre, durable et efficace qui puisse satisfaire les besoins de la société actuelle et future avec le minimum d’impact sur l’environnement. Dans ce cadre, un grand effort de recherche internationale est dévoué à l’étude de nouveaux systèmes de production d’énergie ; réacteurs de fission de Génération IV et réacteurs de fusion nucléaire sont en particulier en train d’être développés. Les matériaux utilisés dans ces réacteurs seront soumis à des hauts niveaux de radiation, ce qui rend nécessaire l’étude de leur comportement sous irradiation pour permette le succès du développement de ces nouvelles technologies. Dans cette thèse, deux matériaux ont été étudiés : la silice amorphe (a-SiO₂) et l’oxyde de magnésium (MgO). Ces deux matériaux sont des oxydes isolants avec des applications dans l’industrie de l’énergie nucléaire. Des irradiations avec des ions de haute énergie ont été réalisées sur différentes plateformes d’accélérateurs d’ions pour induire l’endommagement de ces deux matériaux par irradiation ; ensuite, les mécanismes d’endommagement ont été caractérisés en utilisant, principalement, des techniques d’analyse par faisceau d’ions (techniques IBA).Un des objectifs de cette thèse était de développer la technique d’ionoluminescence (qui est une technique IBA très peu connue) et de l’appliquer à l’étude des mécanismes d’endommagement par irradiation des matériaux, démontrant alors le potentiel de cette technique. L’ionoluminescence de trois types différents de silice (avec des différentes teneurs en OH) a ainsi été étudiée en détail et utilisée pour décrire la création et l’évolution des défauts ponctuels sous irradiation. Dans le cas de MgO, l’endommagement produit par irradiation avec des ions Au⁺ à 1.2 MeV a été caractérisé en utilisant la technique de spectrométrie de rétrodiffusion Rutherford en configuration de canalisation et la diffraction des rayons X. Finalement, l’ionoluminescence de MgO sous différentes conditions d’irradiation a aussi été étudiée. Les résultats obtenus dans cette thèse aident à comprendre les processus d’endommagement par irradiation dans les matériaux, ce qui est indispensable pour le développement de nouvelles sources d’énergie nucléaire
One of the most important challenges in Physics today is the development of a clean, sustainable, and efficient energy source that can satisfy the needs of the actual and future society producing the minimum impact on the environment. For this purpose, a huge international research effort is being devoted to the study of new systems of energy production; in particular, Generation IV fission reactors and nuclear fusion reactors are being developed. The materials used in these reactors will be subjected to high levels of radiation, making necessary the study of their behavior under irradiation to achieve a successful development of these new technologies. In this thesis two materials have been studied: amorphous silica (a-SiO₂) and magnesium oxide (MgO). Both materials are insulating oxides with applications in the nuclear energy industry. High-energy ion irradiations have been carried out at different accelerator facilities to induce the irradiation damage in these two materials; then, the mechanisms of damage have been characterized using principally Ion Beam Analysis (IBA) techniques. One of the challenges of this thesis was to develop the Ion Beam Induced Luminescence or ionoluminescence (which is not a widely known IBA technique) and to apply it to the study of the mechanisms of irradiation damage in materials, proving the power of this technique. For this purpose, the ionoluminescence of three different types of silica (containing different amounts of OH groups) has been studied in detail and used to describe the creation and evolution of point defects under irradiation. In the case of MgO, the damage produced under 1.2 MeV Au⁺ irradiation has been characterized using Rutherford backscattering spectrometry in channeling configuration and X-ray diffraction. Finally, the ionoluminescence of MgO under different irradiation conditions has also been studied.The results obtained in this thesis help to understand the irradiation-damage processes in materials, which is essential for the development of new nuclear energy sources

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23

Roshchupkina, Olga [Verfasser], Jürgen [Akademischer Betreuer] Fassbender, and 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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24

Wiederschein, Frank [Verfasser], Helmut [Akademischer Betreuer] Grubmüller, Bernd [Akademischer Betreuer] Abel, and Marcus [Akademischer Betreuer] Müller. "Investigation of Laser-Induced-Liquid-Beam-Ion-Desorption (LILBID) with Molecular Dynamics Simulations / Frank Wiederschein. Gutachter: Helmut Grubmüller ; Bernd Abel ; Marcus Müller. Betreuer: Helmut Grubmüller." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2010. http://d-nb.info/1043610707/34.

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25

Jafri, Syed Hassan Mujtaba. "Building Systems for Electronic Probing of Single Low Dimensional Nano-objects : Application to Molecular Electronics and Defect Induced Graphene." Doctoral thesis, Uppsala universitet, Tillämpad materialvetenskap, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-160630.

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Nano-objects have unique properties due to their sizes, shapes and structure. When electronic properties of such nano-objects are used to build devices, the control of interfaces at atomic level is required. In this thesis, systems were built that can not only electrically characterize nano-objects, but also allow to analyze a large number of individual nano-objects statistically at the example of graphene and nanoparticle-molecule-nanoelectrode junctions. An in-situ electrical characterization system was developed for the analysis of free standing graphene sheets containing defects created by an acid treatment. The electrical characterization of several hundred sheets revealed that the resistance in acid treated graphene sheets decreased by 50 times as compared to pristine graphene and is explained by the presence of di-vacancy defects. However, the mechanism of defect insertion into graphene is different when graphene is bombarded with a focused ion beam and in this case, the resistance of graphene increases upon defect insertion. The defect insertion becomes even stronger at liquid N2 temperature. A molecular electronics platform with excellent junction properties was fabricated where nanoparticle-molecule chains bridge 15-30nm nanoelectrodes. This approach enabled a systematic evaluation of junctions that were assembled by functionalizing electrode surfaces with alkanethiols and biphenyldithiol. The variations in the molecular device resistance were several orders of magnitude and explained by variations in attachment geometries of molecules. The spread of resistance values of different devices was drastically reduced by using a new functionalization technique that relies on coating of gold nanoparticles with trityl protected alkanedithiols, where the trityl group was removed after trapping of nanoparticles in the electrode gap. This establishment of a reproducible molecular electronics platform enabled the observation of vibrations of a few molecules by inelastic tunneling spectroscopy. Thus this system can be used extensively to characterize molecules as well as build devices based on molecules and nanoparticles.

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26

Šamořil, Tomáš. "Aplikace fokusovaného iontového a elektronového svazku v nanotechnologiích." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-234610.

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Nowadays, the systems that allow simultaneous employment of both focused electron and ion beams are very important tools in the field of micro- and nanotechnology. In addition to imaging and analysis, they can be used for lithography, which is applied for preparation of structures with required shapes and dimensions at the micrometer and nanometer scale. The first part of the thesis deals with one lithographic method – focused electron or ion beam induced deposition, for which a suitable adjustment of exposition parameters is searched and quality of deposited metal structures in terms of shape and elemental composition studied. Subsequently, attention is paid also to other types of lithographic methods (electron or ion beam lithography), which are applied in preparation of etching masks for the subsequent selective wet etching of silicon single crystals. In addition to optimization of mentioned techniques, the application of etched silicon surfaces for, e.g., selective growth of metal structures has been studied. The last part of the thesis is focused on functional properties of selected 2D or 3D structures.

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27

Laxåback, Martin. "Fast wave heating and current drive in tokamaks." Doctoral thesis, KTH, Alfvénlaboratoriet, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-118.

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This thesis concerns heating and current drive in tokamak plasmas using the fast magnetosonic wave in the ion cyclotron range of frequencies. Fast wave heating is a versatile heating method for thermonuclear fusion plasmas and can provide both ion and electron heating and non-inductive current drive. Predicting and interpreting realistic heating scenarios is however difficult due to the coupled evolution of the cyclotron resonant ion velocity distributions and the wave field. The SELFO code, which solves the coupled wave equation and Fokker-Planck equation for cyclotron resonant ion species in a self-consistent manner, has been upgraded to allow the study of more advanced fast wave heating and current drive scenarios in present day experiments and in preparation for the ITER tokamak. Theoretical and experimental studies related to fast wave heating and current drive with emphasis on fast ion effects are presented. Analysis of minority ion cyclotron current drive in ITER indicates that the use of a hydrogen minority rather than the proposed helium-3 minority results in substantially more efficient current drive. The parasitic losses of power to fusion born alpha particles and beam injected ions are concluded to be acceptably low. Experiments performed at the JET tokamak on polychromatic ion cyclotron resonance heating and on fast wave electron current drive are presented and analysed. Polychromatic heating is demonstrated to increase the bulk plasma ion to electron heating ratio, in line with theoretical expectations, but the fast wave electron current drive is found to be severely degraded by parasitic power losses outside of the plasma. A theoretical analysis of parasitic power losses at radio frequency antennas indicates that the losses can be significantly increased in scenarios with low wave damping and with narrow antenna spectra, such as in electron current drive scenarios.
QC 20100506

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28

Popel, Aleksej. "The effect of radiation damage by fission fragments on the structural stability and dissolution of the UO2 fuel matrix." Thesis, University of Cambridge, 2017. https://www.repository.cam.ac.uk/handle/1810/265103.

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The aim of this work was to study the separate effect of fission fragment damage on the structural integrity and matrix dissolution of uranium dioxide in water. Radiation damage similar to fission damage was created by irradiating bulk undoped and doped ‘SIMFUEL’ disks of UO2, undoped bulk CeO2 and thin films of UO2 and CeO2 with high energy Xe and U ions. The UO2 thin films, with thicknesses in the range of 90 – 150 nm, were deposited onto (001), (110) and (111) orientations of single crystal LSAT (Al10La3O51Sr14Ta7) and YSZ (Yttria-Stabilised Zirconia) substrates. The CeO2 thin films were deposited onto single crystal silicon (001) substrates. Part of the bulk UO2 and CeO2 samples, the thin films of UO2 on the LSAT substrates and the thin films of CeO2 were irradiated with 92 MeV 129Xe23+ ions to a fluence of 4.8 × 1015 ions/cm2 to simulate the damage produced by fission fragments in uranium dioxide nuclear fuel. Part of the bulk UO2 and CeO2 samples and the thin films of UO2 on the YSZ substrates were irradiated with 110 MeV 238U31+ ions to a fluence of 5 × 1010, 5 × 1011 and 5 × 1012 ions/cm2 to study the accumulation of the damage induced. The irradiated and unirradiated samples were studied using scanning electron microscopy (SEM), focused ion beam (FIB), atomic force microscopy (AFM), energy dispersive X-ray (EDX) spectroscopy, electron probe microanalysis (EPMA), X-ray diffraction (XRD), electron backscatter diffraction (EBSD), secondary ion mass spectrometry (SIMS) and X-ray photoelectron spectroscopy (XPS) techniques to characterise the as-produced samples and assess the effects of the ion irradiations. Dissolution experiments were conducted to assess the effect of the Xe ion irradiation on the dissolution of the thin film UO2 samples on the LSAT substrates and the bulk and thin film CeO2 samples. The solutions obtained from the leaching of the irradiated and unirradiated samples were analysed using inductively coupled plasma mass spectrometry (ICP-MS). XRD studies of the bulk UO2 samples showed that the ion irradiations resulted in an increased lattice parameter, microstrain and decreased crystallite size, as expected. The irradiated UO2 thin films on the LSAT substrates underwent significant microstructural and crystallographic rearrangements. It was shown that by irradiating thin films of UO2 with high energy, high fluence ions, it is possible to produce a structure that is similar to a thin slice through the high burn-up structure. It is expected that the ion irradiation induced chemical mixing of the UO2 films with the substrate elements (La, Sr, Al, Ta). As a result, a material similar to a doped SIMFUEL with induced radiation damage was produced.

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29

CZELUSNIAK, CAROLINE. "Development of the time-resolved ion beam luminescence technique and its application to the provenance studies of lapis lazuli." Doctoral thesis, 2016. http://hdl.handle.net/2158/1026012.

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The objective of this work was to implement the time-resolved ion beam induced luminescence (TRIBIL) technique at the pulsed beam facility (DEFEL) of the LABEC laboratory. By sending the signal from a detector directly to a sampling ADC, it was possible to perform direct time-resolved measurements.

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30

Nix, Anne-Katrin. "Swift heavy ion irradiation of semiconducting materials - defect production, phase transformation and annealing." Doctoral thesis, 2010. http://hdl.handle.net/11858/00-1735-0000-0006-B4D1-1.

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31

Weng, Peng-Hsiang, and 翁鵬翔. "Time-resolved electro-luminescence & optical beam induced current mapping of photonic devices." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/48051952218798257359.

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碩士
國立中山大學
光電工程研究所
93
In this study we have successfully developed the techniques of time-resolved electro-luminescence (EL) and optical beam induced current (OBIC) microscopy for the mapping of photonic devices. We have applied the techniques to examine various photonic devices, including light emitting diodes (LED), organic light emitting diode (OLED), and coplanar waveguide (CPW) devices. The key development in time-resolved microscopy is the technique of modulation. By measuring the phase delay between the modulation source and the output signal, the response time of the observed devices can be extracted. In electro-luminescence mapping, the phase delay is measured between the applied sinusoidal voltage and the emitted EL, while in OBIC mapping the phase delay is measured between the modulated laser beam and the resulting photocurrent. The phase delay measurements are performed with a lock-in amplifier. In this way, large enhancement in signal-to-noise ratio can also be obtained. Additionally, the technique of varying scanning rate is also developed to synchronize the data acquisition between the LSM and the lock-in amplifier, a key enabling advancement in this thesis study.

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32

Wu, Shang-jie, and 吳尚杰. "Characterizing LED with Time-Resolved Photo-Luminescence and Optical Beam Induced Current Imaging." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/13675978219097126809.

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碩士
國立中山大學
光電工程學系研究所
99
With rapid development of light emitting device, the detection techniques of semiconductor are more and more important, which include time-resolved photoluminescence (TRPL) and optical beam induced current (OBIC) microscopy. In this thesis, we realize the carrier behaviors of active region with multiple quantum wells (MQWs) by these microscopies, and the samples are light emitting diodes (LEDs). However, PL intensity of LEDs increase but OBIC not due to external field compensates, on the other hand, reducing PL lifetime indicates the response time of device shorter with higher reverse bias.

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33

Kupka, Katharina. "Intense heavy ion beam-induced effects in carbon-based stripper foils." Phd thesis, 2016. https://tuprints.ulb.tu-darmstadt.de/5611/1/Dissertation_KatharinaKupka.pdf.

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Amorphous carbon or carbon-based stripper foils are commonly applied in accelerator technology for electron stripping of ions. At the planned facility for antiproton and ion research (FAIR) at the Helmholtzzentrum für Schwerionenforschung (GSI), Darmstadt, thin carbon stripper foils provide an option for directly delivering ions of intermediate charge states to the heavy ion synchrotron, SIS 18, in order to mitigate space charge limitations during high-intensity operation. In case of desired high end-energies in the synchrotron, a second stripping process by a thicker carbon foil provides ions of higher charge states for injection into the SIS18. High beam intensities and a pulsed beam structure as foreseen at FAIR pose new challenges to the stripper foils which experience enhanced degradation by radiation damage, thermal effects, and stress waves. In order to ensure reliable accelerator operation, radiation-hard stripper foils are required. This thesis aims to a better understanding of processes leading to degradation of carbon-based thin foils. Special focus is placed on ion-beam induced structure and physical property changes and on the influence of different beam parameters. Irradiation experiments were performed at the M3-beamline of the universal linear accelerator (UNILAC) at GSI, using swift heavy ion beams with different pulse lengths and repetition rates. Tested carbon foils were standard amorphous carbon stripper foils produced by the GSI target laboratory, as well as commercial amorphous and diamond-like carbon foils and buckypaper foils. Microstructural changes were investigated with various methods such as optical microscopy, scanning electron microscopy (SEM), profilometry and chromatic aberration measurements. For the investigation of structural changes X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, high resolution transmission electron microscopy (HRTEM), in-situ Fourier-transform infrared spectroscopy (FTIR) and small angle X-ray scattering (SAXS) were used. The changes of physical properties, in particular the electrical resistivity, thermal conductivity and stiffness of the foils were studied by in-situ 4-point probe, laser flash analysis and atomic force microscopy, respectively. A technique for measuring temperature of very thin, semitransparent and free-standing stripper foils during irradiation by means of an infrared (IR) camera was developed and applied. The experimental investigations were complemented by molecular dynamics simulations of amorphous carbon exposed to different swift heavy ions. The simulations provide information on the structural changes in the tracks at atomic scale. Virtual amorphous carbon cells were created by simulating liquid quenching and plasma deposition, yielding cells with different degrees of clustering of sp2 and sp3 bonding. The impacts of swift heavy ions were modeled by an instantaneous energy deposition deduced from inelastic thermal spike model calculations. Results of experiments and simulations provide evidence for the beam-induced transformation of amorphous carbon to a defected graphitic structure and for clustering of sp2 and sp3 bonds. These structural changes result in severe property changes. The electrical and thermal properties of amorphous carbon seem to improve during beam exposure, but the mechanical properties degrade severely. The beam conditions have a strong influence on the evolution of induced structure and property changes. A better understanding of the response of (amorphous) carbon stripper foils to swift heavy ion beams as revealed by dedicated irradiation and characterization experiments performed within this thesis, provides criteria for material requirements for future stripper foils used in high-power heavy ion accelerators such as FAIR.

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34

Liu, Pang-Lun, and 劉邦倫. "Magnetism in semiconductor (Ge and Si) films induced by ion-beam sputtering." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/24738640312489987108.

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碩士
國立臺灣海洋大學
材料工程研究所
97
This thesis reports the magnetism in semiconductor (Ge and Si) nanostructures induced by ion-beam sputtering. Ge films and Si films were prepared at different temperatures by magnetron sputtering. The room-temperature ferromagnetism was observed from Ge and Si which are sputtered with different Ar+ ion energies. At room temperature and low temperature the various magnetic moment that depends on different bombardment ions, bias and bombardment quantity could be observed. Before bombarding, the magnetic properties of the Ge and Si films were observed and no magnetic impurities were found in the thin films. By Ar+ ion bombard with bias 1kV, dose 4.7×1014, the maximum magnetism of Ge and Si thin films was obtained than other gas-ions (He, Ne, N2, O2). The reason is probability that the momentum of ions is lower than Ar+. The maganetization was relatively small when the bias of acceleration was lower or higher than 1kV. When the quantity was lower than 1014 or exceed 1×1015 the magnetic moment was observed. Our conclusion is the magnetic moment that was found in the proper range. After the Ge and Si thin films magnetic moment were annealed, the magnetic moment was slightly changed.

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35

Prosvetov, Alexey. "Ion-beam induced modifications of structural and thermophysical properties of graphite materials." Phd thesis, 2020. https://tuprints.ulb.tu-darmstadt.de/13253/7/2020.08.15%20PhD%20Thesis%20Prosvetov.pdf.

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With further development of high-power accelerators and nuclear reactors, there is a strong demand for structural materials that can withstand extreme operational conditions, e.g., large heat loads, mechanical and thermal stresses, high intensity and long-term ion irradiation. Carbon-based materials show excellent thermal transport properties and thus efficient heat dissipation required for such applications. Under ion beam irradiation, graphite also has the advantage of lower stopping power and lower radiation induced activation compared to metals. For these reasons, polycrystalline graphite is commonly used in extreme radiation environments, e.g. beam dumps. In the past, neutron-irradiation effects in graphite have been studied in detail, whereas data on material behavior under exposure to high-energy ion beams is scarce. This thesis focuses on changes of structural and thermophysical properties induced by swift heavy ion irradiation in well-oriented flexible graphite (FG) and in fine-grained isotropic polycrystalline graphite (PG). To investigate radiation-induced degradation processes, graphite samples were irradiated with 4.8 and 5.9 MeV/u 12C, 48Ca, 129Xe, 197Au, and 238U ions with fluences up to ~2×10^14 ions/cm2 at the UNILAC accelerator of the GSI Helmholtz Centre for Heavy Ion Research, Darmstadt. Structural transformations along the ion range were monitored by Raman spectroscopy complemented by scanning electron microscopy. The corresponding modifications of thermophysical properties were characterized using laser flash analysis and frequency domain photothermal radiometry. The response of FG and PG to high-energy ion beams is shown to be quite different, which is ascribed to the different initial microstructure and microtexture of these graphite materials. Radiation damage in flexible graphite follows the trend of the nuclear energy loss and yields a weak or no correlation with the electronic energy loss up to 30 keV/nm. The density of point defects produced via elastic collisions monotonously increases along the ion range and causes a pronounced thermal diffusivity degradation from ~550 down to 50 mm2/s for the Au ion irradiation at a fluence of ~1×10^14 ions/cm2. In contrast, in polycrystalline graphite, both nuclear and electronic (above a certain threshold) energy loss contribute to material modifications. Raman spectroscopy reveals the same type of damage for low Z (Ca) and high Z (Au, U) ions at the end of the ion range (last ~15 µm), where the nuclear energy loss is maximal. Within the range section dominated by the electronic energy loss, the irradiation with Au and U ions (high energy loss of 20-25 keV/nm) causes significant disordering, crystallite refinement and misalignment as well as partial amorphization. At the highest applied fluence of 5×10^13 ions/cm2, this leads to a structure similar to glassy carbon. Exposure to Ca ions of the same fluence produces just a slight increase of the defect density. The corresponding drop of the thermal diffusivity is from 80 mm2/s (virgin) to ~5 mm2/s for Au ions and to ~70 mm2/s for Ca ions. Damage cross-sections in both graphite materials are calculated based on the evolution of the Raman parameters and thermophysi-cal properties as a function of fluence. Raman parameters assigned to the lattice disorder and thermal diffusivity values show a strong correlation, providing the possibility to estimate heat transfer properties of graphite materials by means of Raman spectroscopy.

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36

Huang, Guo-Ting, and 黃國庭. "The study of surface morphology and composition of ion beam induced silicon oxide in different ion energy." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/72030769265798123942.

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Анотація:

碩士
國立中央大學
機械工程研究所
95
Presently, silicon dioxide is the popular material for insulators in semiconductor. In this article, we use the technique Ion Beam Induced Oxidation(IBIO). Our laboratory had successfully been manufacturing Silicon dioxide use our system at substrate in room temperature and 650℃. Silicon dioxide will be growing as the ion beam current and oxygen increase. It shows that at room temperature, beam current 4μA, oxygen pressure at 1×10-4Torr, we can obtain the most silicon dioxide. In this article, we treat the silicon substrate with different ion energy(9keV、7keV、5keV) at room temperature and 650℃.We fixed the ion dose at 4.57×1017ions/cm2, and oxygen pressure at 1×10-4Torr. The result shows that at room temperature ion beam with the energy 5keV can produce more SiO2, and in top layer, the concentration of SiO2 is 98.1%. However, 9keV ion beam can produce SiO2 in deeper layer. At 650℃,the concentration of SiO2 is boosted as beam energy increase. In addition, the silicon surface will be rough after ion bombardment. The surface becomes more rough with beam energy increase.

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37

Wiederschein, Frank. "Investigation of Laser-Induced-Liquid-Beam-Ion-Desorption (LILBID) with Molecular Dynamics Simulations." Doctoral thesis, 2010. http://hdl.handle.net/11858/00-1735-0000-0006-B4E5-6.

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38

Müller, Georg Alexander. "Ion-beam induced changes of magnetic and structural properties in thin Fe films." Doctoral thesis, 2004. http://hdl.handle.net/11858/00-1735-0000-0006-B4EE-3.

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39

Cheng, Eugene, and 程友均. "The Study of O2+ ion beam milling Si(110) induced roughness and enhanced secondary ion yield in secondary ion mass spectrometry." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/48591610985222347975.

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碩士
國立彰化師範大學
機電工程學系
97
The objective of this thesis is a study of the variation of Si(110) induced roughness and enhanced secondary ion yield by varying the energy level of primary ion milling on slicon substrate in secondary ion mass spectrometry(SIMS). They are separated by three parts. The first part is dealing with the relationship between surface roughness and secondary ion yield, when primary ion emitted on silicon substrate under different depths. The result indicates that both of surface roughness and ripple are significantly affected by the primary O2+ ion. In general, the surface roughness and ripple increase with the O2+ crater in depth. In addition, it shows that the variation of surface roughness decreases with the increase of energy level of the primary O2+ ion, for example, from 2keV to 6keV. In the second part, two different kinds of ions, O2+ and Cs+, with the same energy level being chosen, the result shows that after ion beam bombardment, the variation of surface roughness is slightly affected by Cs+ primary ion. The third part is to study the effect produced by the focus and de-focus primary O2+ ion beam in different depths on surface roughness. Itindicates that only minor change of the surface roughness was observed when focus and de-focus ion beam bombardment are selected.

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40

Stacco, Jacques S. "Observation of Analyte-Induced Deflections for Uncoated Microcantilevers using the Focused Ion Beam Procedure." 2008. http://trace.tennessee.edu/utk_gradthes/454.

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It has been found that structural modifications, involving the creation of submicron scale grooves on uncoated silicon nitride microcantilevers, allow microcantilevers to display analyte-induced deflections which have not been previously observed. The submicron grooves were created through the use of a focused ion beam procedure to mill deep and narrow grooves without the subsequent deposition of a chemically reactive coating. These modifications significantly increase (by approximately 400%) an uncoated microcantilever’s ability detect analytes such as water vapor, ethyl alcohol, acetone vapor, argon, and 1-mononitrotoluene. The intention of the experiment was to achieve greater microcantilever deflections by increasing an uncoated microcantilever’s surface energy and surface area through the least amount of surface modifications. Accordingly, one to three grooves with a depth greater than the thickness of the microcantilevers were achieved by milling the grooves at a maximum angle of 45 degrees. One microcantilever, with a 100 nm wide groove (milled at an angle of 45 degrees relative to the surface normal and to a depth of 1.3 micrometers) deflected by 400 nm in the presence of an argon-ethanol mixture. The same microcantilever also exhibited a deflection magnitude which increased with gas concentration. When comparing the set of milled microcantilevers used in this experiment, deflections were found to increase as the width of the grooves decreased and the depth and number of grooves increased.

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41

Yu, Chin-Shun, and 余錦順. "The study of the Ion Beam induced the topography and the oxidation of silicon." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/hcj9c8.

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Анотація:

碩士
國立中央大學
機械工程研究所
94
The Ion Beam applied to the material is mainly divided into two aspects. The Ion Beam Synthesis is the new technology which includes the Ion Beam and Physical of Chemical Vapor Deposition. Ion Beam Assisted Deposition (IBAD) and Ionized Cluster Beam (ICB) has been developed since 1970s. On the other hand, ions with the different energy is implanted into the material surface layer in order to achieve the improvement of the properties of the material surface. In the development of IC technology, oxide’s main achievement is the gate extreme insulation. After the component is insulated, the gate voltage may switch off the control channel, and Carries can’t be lost between source and drain. Therefore, the quality of insulation affects the properties. There are many methods of coating technology and there will be impurity in the CVD and the defect caused by residual stress from the high temperature in the process of thermal oxidation. In order to remove the high temperature and impurity, this paper will discuss the method of bombarding silicon with different beam currents in oxygen environment to produce the oxidized thin film, using Ion Beam System in the high vacuum with the pressure of 5 10-8 Torr in pure environment.

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42

Yuan, Faqing. "RNA-metal ion interactions and metal ion- induced conformational change in the spliceosomal U2-U6 snRNA complex studied by lanthanide ion luminescence and resonance energy transfer techniques." 2008. http://etd.lib.fsu.edu/theses/available/etd-04122008-213549.

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Thesis (Ph. D.)--Florida State University, 2008.
Advisors: Nancy L. Greenbaum [and] Geoffrey F. Strouse, Florida State University, College of Arts and Sciences, Dept. of Chemistry & Biochemistry. Title and description from dissertation home page (viewed June 20, 2008). Document formatted into pages; contains xv, 120 pages. Includes bibliographical references.

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43

Chen, Nai-Hui, and 陳迺惠. "Strain and Optical Characteristics Analysis of Mg Ion-Implanted GaMnAs Diluted Magnetic Semiconductor Fabricated by Ion Beam Induced Epitaxial Crystallization." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/tdq9pk.

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Анотація:

碩士
國立交通大學
電子研究所
107
The GaMnAs diluted magnetic semiconductor (DMS) has attracted much attention in the past two decades because of its physical models and potential applications in spintronics. In order to increase the Curie temperature of GaMnAs, it is necessary to increase the Mn content in GaMnAs. However, as increasing the Mn content will easily damage the lattice structure with ion implantation. In this study, we used helium ion beam induced epitaxial crystallization (He-IBIEC) as an annealing method. The penetrating helium ions will heat the damage region and regrow the thin film in a very short time to prevent Mn atoms from gathering and precipitating into secondary-phase clusters. After annealing the GaMnAs thin film under different energy of helium ions, we analyzed the bandgap energy of the GaMnAs thin film in relation to the crystalline quality and strain. In order to increase the spin signal in GaMnAs, we provided excess carriers into the substrate by Mg ions implantation. The effective concentrations of Mg were 0.5%, 1%, 2% and 4%, respectively. Then, we implanted 2.6% Mn ions into GaAs: Mg samples. Subsequent use of the heavy ion accelerator and the Van de Graaff accelerator to repair the samples by He-IBIEC annealing method under 350 keV and 1 MeV, respectively. The experimental results show that the helium ion annealing has a significant effect on the lattice constant through the (004) ω-2θ measurement of the high-resolution X-ray diffraction, and the full width at half maximum (FWHM) of the GaMnAs signal is reduced, that indicate the improvement of the crystal quality. In the RSM result which indicates that samples remained fully strained and the stress does not release. Then, the Raman measurement is used to observe the strain of the sample, because the peak shift of longitudinal optical mode is relate to strain. The peak shift is found to decrease with increasing the energy of helium ions. Based on the Raman signal intensity ratio of longitudinal optical and transverse optical mode of GaAs, the crystal quality of the sample is improved after annealing. The transmittance and reflectance were measured by a spectrophotometer. The bandgap energy of the GaMnAs thin film was extracted using Tauc plot method, and it is found that IBIEC annealing treatment increased the bandgap energy of GaMnAs. The increment of Mg ions concentration make the lattice constant larger but still remained fully strained. When the Mg ions concentration is increased, the overall crystal quality is deteriorated. And it needs annealed with 1 MeV to have enough energy to repair the crystal structure.

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44

Batra, Nitin M. "Device Fabrication and Probing of Discrete Carbon Nanostructures." Thesis, 2015. http://hdl.handle.net/10754/552679.

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Анотація:

Device fabrication on multi walled carbon nanotubes (MWCNTs) using electrical beam lithography (EBL), electron beam induced deposition (EBID), ion beam induced deposition (IBID) methods was carried out, followed by device electrical characterization using a conventional probe station. A four-probe configuration was utilized to measure accurately the electrical resistivity of MWCNTs with similar results obtained from devices fabricated by different methods. In order to reduce the contact resistance of the beam deposited platinum electrodes, single step vacuum thermal annealing was performed. Microscopy and spectroscopy were carried out on the beam deposited electrodes to follow the structural and chemical changes occurring during the vacuum thermal annealing. For the first time, a core-shell type structure was identified on EBID Pt and IBID Pt annealed electrodes and analogous free standing nanorods previously exposed to high temperature. We believe this observation has important implications for transport properties studies of carbon materials. Apart from that, contamination of carbon nanostructure, originating from the device fabrication methods, was also studied. Finally, based on the observations of faster processing time together with higher yield and flexibility for device preparation, we investigated EBID to fabricate devices for other discrete carbon nanostructures.

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45

Khalil, Ali Saied. "Heavy-Ion-Irradiation-Induced Disorder in Indium Phosphide and Selected Compounds." Phd thesis, 2007. http://hdl.handle.net/1885/47462.

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Анотація:

Indium phosphide (InP) is an important III-V compound, with a variety of applications, for example, in light emitting diodes (LED), InP based photonic crystals and in semiconductor lasers, heterojunction bipolar transistors in integrated circuit applications and in transistors for microwave and millimeter-wave systems. The optical and electrical properties of this compound can be further tailored by ion implantation or prospectively by swift heavy ion beams. ¶ Thus knowledge of ion-induced disorder in this material is of important fundamental and practical interest. However, the disorder produced during heavy ion irradiation and the subsequent damage accumulation and recovery in InP is far from being completely understood. In terms of the damage accumulation mechanisms, the conclusions drawn in the numerous studies performed have often been in conflict with one another. A factor contributing to the uncertainties associated with these conflicting results is a lack of information and direct observation of the “building blocks” leading to the ultimate damage created at high ion fluences as an amorphous layer. These building blocks formed at lower fluence regimes by single ion impacts can be directly observed as isolated disordered zones and ion tracks for low energy and swift heavy ion irradiation, respectively. ¶ The primary aim of this work has thus been to obtain a better understanding of the disorder in this material through direct observations and investigation of disorder produced by individual heavy ions in both energy regimes (i.e. elastic and inelastic energy deposition regimes) especially with low ion fluence irradiations. In this thesis the heavy ion induced disorder introduced by low energy Au ions (100 keV Au+) and high energy Au (200 MeV Au+16) ion irradiation in InP were investigated using Transmission Electron Microscopy (TEM), Rutherford Backscattering Spectrometry (RBS/C) and Atomic Force Microscopy (AFM). ¶ ...

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46

Chen, Jan-Jim, and 陳加展. "The thermal effect of the Ar ion beam induced the topography abd the oxidation of silicon." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/72wkda.

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Анотація:

碩士
國立中央大學
機械工程研究所
94
In the industry of semiconductor it used many ways for well quality of SiO2. In my paper I use the way of IBIO to make it. First I put my sample into the vacuum chamber, second the sample is heated up 650℃, then I put oxygen into the chamber around the sample, final the ion of Ar bombardment the oxygen to put into silicon. In order to know the oxygen can putted into the silicon to form SiO2, I used X-ray Photoelectron Spectroscopy(XPS) to study the composition of the sample to sure it is existed SiO2. At the same time I also used Atomic Force Microscope(AFM) to measure the topography to observe the change of the sample after experiment. In the result of XPS, we can know that it has the element signal of the silicon、oxygen and carbon, then we analyze the signal of element silicon, we find it has two peak value in the 103ev and 99ev；In the result of AFM, we find the surface becoming roughened by the ion bombardment at high temperature. It is changed by the concentration of the oxygen and the intensity of the ion beam.

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47

Beraki, Kidane Belay. "The influence of ion beam-induced non-stoichiometry on the solid-phase epitaxial growth of amorphised GaAs." Phd thesis, 1999. http://hdl.handle.net/1885/147315.

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48

Hsieh, Tien-Yu, and 謝典祐. "Annealing induced oxidation, transformation, and orientation with substrate of Zr thin film prepared by Ion Beam Deposition." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/72472761031329469613.

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碩士
國立中山大學
材料科學研究所
93
Nanocrystalline α-Zr condensates deposited by ion beam sputtering on the NaCl (100) surfaces and then annealed at 100 oC to 750 oC in air. The phases present were identified by transmission electron microscopy to be nanometer-size α-Zr+ZrO、α-Zr+ZrO+c-ZrO2、c-ZrO2、c-+t-ZrO2、t-ZrO2、and t-+m-ZrO2 phase assemblages with increasing annealing temperature. The zirconia showed strong {100} preferred orientation due to parallel epitaxy with NaCl (100) when annealed between 150 oC and 500 oC in air. The c- and t-zirconia condensates also showed (111)-specific coalescence among themselves. The c- and/or t-ZrO2 formation can be accounted for by the small grain size, the presence of low-valence Zr cation and the lateral constraint of the neighboring grains.

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49

Müller, Georg Alexander [Verfasser]. "Ion-beam induced changes of magnetic and structural properties in thin Fe films / vorgelegt von Georg Alexander Müller." 2004. http://d-nb.info/971021570/34.

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50

Lai, Ying-Yu, and 賴盈妤. "Fabrication of Electrode-SWNT-Electrode Platform for Inelastic Electron Tunneling Spectroscopy by Focused Ion/Electron Beam-induced Deposition." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/6u55sp.

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Анотація:

碩士
國立臺灣大學
化學研究所
103
Forming stable MMM (Metal-Molecule-Metal) junctions is a fundamental method for studying electric properties of a tailored single molecule. Low successful rates (< 10%) of fabricating three-electrode single-molecular transistor (SMT) by electromigration provokes us to propose a new molecular electronic platform: Synthesize “m-SWNT−Molecule−m-SWNT” (metallic single-walled carbon nanotube) configurations first, and then deposit metal film electrodes by FIBD or FEBID (focused ion/electron beam-induced deposition). So far, Pt−m-SWNT−Pt devices have been fabricated and measured. Unexpected results are attributed to deposition mechanism of FIBD or FEBID. FIBD Part: Electrodes deposited by FIBD are always surrounded by “halo” structure. While the distance of two electrodes is less than 500 nm, leakage current arising from overlap of nearby platinum halo of two electrodes would be measured. Temperature-variable I−V result shows that conductance of Pt−m-SWNT−Pt device decreases with temperature, which is not consistent with m-SWNT characteristic. Besides, IETS (inelastic electron tunneling spectroscopy) peaks corresponding to vibrational modes of m-SWNT such as radial breathing mode (100~350 cm‒1) and carbon-carbon bond stretching of graphite-like material, G band (~1600 cm‒1) are nearly undetectable. FEBID Part: Platinum halo less extend in FEBID. IETS signals of m-SWNT are detected. However, the amount of “remaining carbon residue” in the platinum electrodes is so significant that it result in lower conductance of device (~0.025 G0), which is much less than quantum conductance of m-SWNT (2 G0). It is also presumed that discrepancy of temperature-variable I−V result also comes from less quantity of “platinum”. In summary, owing to deposition mechanism of FIBD and FEBID, some features of m-SWNT are not observed in Pt−m-SWNT−Pt devices. Adjusting fabrication parameters or introducing other lithography may improve device performance.

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Дисертації з теми "Ion beam induced luminescence"

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