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NDE applications in microelectronic industriesMeyendorf, N., Oppermann, M., Krueger, P., Roellig, M., Wolter, K. J. 30 August 2019 (has links)
New concepts in assembly technology boost our daily life in an unknown way. High end semiconductor industry today deals with functional structures down to a few nanometers. ITRS roadmap predicts an ongoing decrease of the “DRAM half pitch” over the next decade. Packaging of course is not intended to realize pitches at the nanometer scale, but has to face the challenges of integrating such semiconductor devices with smallest pitch and high pin counts into systems. Advanced techniques of nondestructive evaluation (NDE) with resolutions in volume better than 1 micrometer vixen size are urgently needed for the safety and reliability of electronic systems, especially those that are used in long living applications. The development speed of integrated circuits is still very high and is not expected to decrease in the next future. The integration density of microelectronic devices is increasing, the dimensions become smaller and the number of I/O's is getting higher. The development of new types of packages must be done with respect to reliability issues. Potential damage sources must be identified and finally avoided in the new packages.
In power electronics production the condition monitoring receives a lot of interest to avoid electrical shortcuts, dead solder joints and interface crac king. It is also desired to detect and characterize very small defects like transportation phenomenon or Kirkendall voids. For this purpose, imaging technologies with resolutions in the sub-micron range are required.
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[pt] EMPREGO DE MICROSCOPIA DE FORÇA ATÔMICA E NANOINDENTAÇÃO NA CARACTERIZAÇÃO TRIBOMECÂNICA DE MINERAIS E MATÉRIA ORGÂNICA: UMA APLICAÇÃO EM FOLHELHOS DA FORMAÇÃO IRATI / [en] USE OF ATOMIC FORCE MICROSCOPY AND NANOINDENTATION IN THE TRIBOMECHANICAL CHARACTERIZATION OF MINERALS AND ORGANIC MATTER: ON SHALE OF THE IRATI FORMATIONDOUGLAS LUIZ PINTO DE LACERDA 04 February 2021 (has links)
[pt] Folhelhos desempenham tanto a função de rocha capeadora, camada
de rocha de baixa permeabilidade que contém os hidrocarbonetos no reservatório
, quanto de rocha geradora de petróleo em sistemas petrolíferos convencionais.
Mais recentemente passaram a ser exploradas como reservatórios
não convencionais. As suas propriedades mecânicas são importantes na determinação
da estabilidade estrutural de poços e na avaliação da fraturabilidade
de reservatórios não convencionais. Além disso, permitem a conexão
entre os dados de prospecção de petróleo e as características geoquímicas
da rocha geradora. Nesta tese, as propriedades nanomecânicas de amostras
de folhelho Irati, provenientes da Bacia do Paraná, foram caracterizadas
por microscopia de força atômica e nanoindentação em conjunto com microscopia
eletrônica de varredura. Procedimentos de processamento de imagens
foram desenvolvidos para construir imagens de propriedades tribomecânicas
dos minerais e da matéria orgânica presentes na superfície. A identificação
mineralógica realizada no microscópio eletrônico permitiu associar o contraste
verificado nas imagens obtidas no microscópio de força atômica às
propriedades tribomecânicas dos minerais e matéria orgânica. Esses constituintes
do folhelho também foram caracterizados por nanoindentação para
permitir a medida de duas propriedades mecânicas por um método independente.
Por fim, um conjunto de nanoindentações aleatoriamente distribuídas
na superfície foi executada em uma amostra da mesma região, sendo
o resultado estatisticamente analisado para permitir a comparação com as
propriedades macroscópicas. / [en] Shales perform both the cap rock, low permeability rock layer that
restrain hydrocarbons in the reservoir, and petroleum source rock in conventional
petroleum systems. More recently they have been exploited as
unconventional reservoirs. Their mechanical properties are important in determining
the structural stability of wells and in evaluating the fracability
of unconventional reservoirs. In addition, they allow the connection between
oil prospecting data and the geochemical characteristics of the source rock.
In this thesis, the nanomechanical properties of Irati shale samples from the
Paraná Basin were characterized by atomic force microscopy and nanoindentation
together with scanning electron microscopy. Image processing procedures
were developed to construct images of tribomechanical properties
of minerals and organic matter present on the surface. The mineralogical
identification performed by electron microscopes allowed to associate the
contrast found in the images obtained with the atomic force microscope to
the tribomechanical properties of minerals and organic matter. These shale
constituents were also characterized by nanoindentation to allow the measurement
of two mechanical properties by an independent method. Finally, a
set of randomly distributed nanoindentations on the surface was performed
on a sample from the same region, and the result was statistically analyzed
to allow comparison with macroscopic properties.
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Multimodal structural, compositional, and mechanical characterization of cortical bone on the micron scaleSchrof, Susanne 31 July 2017 (has links)
Schlüsselfaktoren der bemerkenswerten mechanischen Eigenschaften von Knochen sind seine
komplexe hierarchische Struktur und chemische Zusammensetzung. Ziel dieser Dissertation war die simultane Untersuchung von Materialkomposition und 3D Struktur in Relation zu lokalen elastischen Eigenschaften von Knochengewebe unter Verwendung von neuen hochauflösenden experimentellen Konzepten. Im ersten Teil wurde polarisierte Raman Spektroskopie (PRS) eingesetzt um gesunden humanen kortikalen Knochen zu analysieren. Es konnte gezeigt werden, dass sich PRS eignet, um sowohl die chemische Zusammensetzung als auch die 3D Organisation der Kollagenfasern in einer Messung aufzuklären. Dominante Faserorientierungen ganzer Gewebedomänen konnten identifiziert
und mit der Koexistenz zweier Faserorganisationsmuster verknüpft werden. Durch Kombination derPRS Experimente mit ko-lokalisierten Synchrotron-Phasenkontrast-Nano-Tomografie- undUltraschallmikroskopie-Messungen wurde eine komplementäre Untersuchung von Faserarchitektur, chemischer Komposition und elastischen Eigenschaften einzelner Knochenlamellen ermöglicht. Die multimodale Analyse ergab, dass die charakteristischen lamellären Ondulationen der Elastizität in erster Linie durch sich lokal ändernde Faserorientierungen bedingt werden und nicht durch Variationen der Materialzusammensetzung, Abweichungen der Mineralkristallpartikeleigenschaften
oder durch Fluktuationen der Massendichte. Im letzten Teil wurde mittels akustischer Mikroskopie der Einfluss der Mutation des Neurofibromin 1 Genes auf die pathologische Entwicklung von mechanischen Knocheneigenschaften untersucht. Anhand zweier Knockout-Mausmodelle wurde festgestellt, dass nur eine Mutation in frühen mesenchymalen Vorläuferzellen die Steifigkeit der langen Röhrenknochen signifikant beeinträchtigt. Perspektivisch eignet sich der vorgestellte multimodale Ansatz für nicht-destruktive Charakterisierung eines breiten Spektrums biologischer und synthetischer Faserverbundwerkstoffe. / Key factors determining the remarkable mechanical performance of bone are its material composition and complex hierarchically structure. The aim of this thesis was the concurrent investigation of the chemical composition and 3D structure of bone tissue in relation to the local elastic properties by introducing novel high resolution experimental approaches. In the first part, polarized Raman spectroscopy (PRS) was applied to analyze healthy human cortical bone. In particular, it was demonstrated that PRS can be employed to simultaneously investigate the chemical composition and the 3D organization of collagen fibrils in a single experiment. Predominant fibril orientations in entire tissue domains were identified and linked to the coexistence of two fibril organization patterns. To further extend the analysis, PRS experiments were combined with synchrotron X-ray phase contrast nano tomography and scanning acoustic microscopy measurements in a site-matched study design. This multimodal approach enabled complementary imaging of the fibrillar architecture, tissue composition and resulting elastic properties of single bone lamellae. In line with earlier studies, crosscorrelation analysis strongly suggested that the characteristic elastic undulations of bone lamellae are the result of the twisting fibrillar orientation, rather than compositional variations, modulations of the mineral particle maturity, or mass density fluctuations. Finally, acoustic microscopy was applied to analyze the impact of the neurofibromin 1 gene mutation on the pathologic development of the mechanical properties of bone. Analysis of two knock-out mouse models revealed that only Nf1 ablation in early mesenchymal progenitor cells significantly impairs the elastic stiffness of long bones. In future studies, the presented multimodal methodology can be translated for non-destructive and high resolution characterization of a broad range of biological and synthetic fiber composite materials.
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Quantitative ultrasound in transverse transmission for bone quality assessment and monitoring fracture healingRohrbach, Daniel 04 September 2013 (has links)
Osteoporose und gestörte Heilungsverläufe von Knochenbrüchen verursachen immer noch beachtliche klinische Komplikationen. Ein vielversprechender Ansatz für die nichtinvasive und nichtionisierende Abschätzung des Frakturrisikos und der Bildgebung von Frakturheilung ist quantitativer Ultraschall (QUS). Dennoch liegt die derzeitige Akzeptanz für die Knochenqualitätsabschätzung noch weit hinter herkömmlichen röntgenbasierten Anwendungen. Es wurden akustische Mikroskopie und Synchrotronstrahlen-Mikrotomographie für die Anatomie und altersabhängige Erfassung von strukturellen und elastischen Variationen auf der mikroskopischen Ebene von humanen Femora verwendet. Die gewonnenen Daten dienten als Grundlage für die Erstellung mikromechanischer Modelle von Knochen für numerische Simulationen der Schallausbreitung im humanen Femurhals. Dabei wurde der Aufbau eines US-basierten Femur-Scanners in transversaler Transmission (TT) nachempfunden. Im letzten Abschnitt der Arbeit wurde QUS in TT in in vitro Experimenten am Rattenfrakturmodell auf eine Anwendung für die Bildgebung der Frakturheilung getestet. Die Studien konnten zeigen, dass ein Großteil der adaptiven Fähigkeiten von Knochen auf mikroskopischer Ebene auf eine Kombination von extrazellulärer Matrixelastizität und Gewebeporosität zurückzuführen ist. Die Simulationen des zweiten Teils konnten die Existenz von geführten Wellen im humanen Femurhals bestätigen. Die sensitive Abhängigkeit von US-parametern von frakturrelevanten Knocheneigenschaften zeigt das hohe Potential von QUS für die Frakturrisikoabschätzung. Der zweite Teil der Arbeit konnte erfolgreich die Möglichkeit von QUS in TT zur Diskriminierung von zeitigen Heilungsstadien demonstrieren. Zusammenfassend bestätigt die Studie das hohe Potential von QUS für die Frakturrisikoabschätzung und die Bildgebung der Frakturheilung. / Osteoporosis and impaired bone healing are of high relevance. A promising non-invasive, non-ionizing candidate for fracture risk prediction and monitoring fracture healing is quantitative ultrasound (QUS). However, the acceptance of QUS for bone quality assessment is still not comparable to X-ray based methods. Scanning acoustic microscopy (SAM) and Synchrotron Radiation micro-computer tomography (SRµCT) has been used to investigate anatomical and age dependent variations of micro elastic, structural and mineralization parameters at the tissue level of human femoral bone. Femoral neck models were created based on these data for numerical sound propagation simulations emulating a transverse transmission (TT) setup of an in vivo QUS prototype. In the last part of the project the TT approach has been tested in ex vivo experiments in a rat healing model. The power of QUS, to discriminate two early healing stages has been compared to µCT measurements at the same specimens. It was found that the major contributor to bone adaptation is related to a combination of extracellular matrix elasticity and tissue porosity. It is hypothesized that these parameters are likely to have a considerable impact on the reliability of in silico models. The simulations of the second part confirmed the existence of guided wave propagation in the cortical shell and a high dependency of US parameters on fracture relevant bone properties. The results demonstrate the high potential for bone fracture risk prediction at the femoral neck using QUS. Finally, it was successfully demonstrated that early healing stage discrimination of QUS in TT was superior compared to µCT. In summary these investigations not only show the importance for a precise estimation of micro mechanical properties for numerical modelling but also demonstrate the feasibility and high potential of QUS for bone quality assessment and monitoring of fracture healing.
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