Dissertations / Theses on the topic 'Transmissionselektronenmikroskopie'
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Mühle, Uwe. "Spezielle Anwendungen der Transmissionselektronenmikroskopie in der Siliziumhalbleiterindustrie." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2015. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-160699.
Full textThe strong improvements in functionality and productivity in the semiconductor industry are mostly a result of the decrease of structural details on a logarithmic scale during the last decades. The monitoring of the production process, as well as failure analyses, utilize methods of transmission electron microscopy. For targeted preparations of semiconductor structures, techniques based on focused ion beams are established, with adaptions to the current task. The imaging of structural details with dimensions of a few nanometers requires the application of different contrast techniques, depending on the detailed request. Different opportunities of elemental analysis, such as energy dispersive X-ray analysis or electron energy loss analysis, deliver additional information about the chemical composition and binding states on a nanoscale. The use of scanning transmission electron microscopy enables a direct combination of imaging and elemental analysis. The local distribution of dopants, as one of the major basics for the function of semiconductor devices, can be observed via the phase shift of the transmitted electron wave only. This influence requires the application of electron holography, a technique which enables the visualization of the process result of implantations or diffusion processes. The characterization of details which are smaller than the thickness of a TEM-sample is enabled through the use of electron tomography. This technique requires special strategies for preparation and imaging and delivers a 3D-dataset, describing the structure
Wahl, Claudia. "Charakterisierung innerer Grenzflächen in mikrokristallinem SiO2 mit Transmissionselektronenmikroskopie." [S.l.] : [s.n.], 2002. http://elib.tu-darmstadt.de/diss/000197.
Full textGramm, Fabian. "Kombination von Transmissionselektronenmikroskopie und Pulverbeugungsdaten zur Lösung von komplexen Zeolithstrukturen." kostenfrei, 2007. http://e-collection.ethbib.ethz.ch/view/eth:29878.
Full textKobler, Aaron. "Untersuchung der Deformationsmechanismen in nanostrukturierten Metallen und Legierungen mit Transmissionselektronenmikroskopie." Phd thesis, TUPrints, 2015. http://tuprints.ulb.tu-darmstadt.de/4432/1/phd_thesis_ak.pdf.
Full textHettler, Simon Josef [Verfasser], and D. [Akademischer Betreuer] Gerthsen. "Transmissionselektronenmikroskopie mit elektrostatischen Zach-Phasenplatten / Simon Josef Hettler. Betreuer: D. Gerthsen." Karlsruhe : KIT-Bibliothek, 2015. http://d-nb.info/1071894293/34.
Full textGamm, Björn [Verfasser], and D. [Akademischer Betreuer] Gerthsen. "Phasenkontrast in der Transmissionselektronenmikroskopie mit elektrostatischen Phasenplatten / Björn Gamm. Betreuer: D. Gerthsen." Karlsruhe : KIT-Bibliothek, 2013. http://d-nb.info/1032243058/34.
Full textObermair, Martin [Verfasser], and D. [Akademischer Betreuer] Gerthsen. "Phasenkontrast-Transmissionselektronenmikroskopie mit Dünnfilm- und elektrostatischen Phasenplatten / Martin Obermair ; Betreuer: D. Gerthsen." Karlsruhe : KIT-Bibliothek, 2021. http://d-nb.info/1233359126/34.
Full textWild, Johannes [Verfasser], and Josef [Akademischer Betreuer] Zweck. "Lorentz-Transmissionselektronenmikroskopie und Differentielle Phasenkontrastmikroskopie an magnetischen Skyrmionen / Johannes Wild ; Betreuer: Josef Zweck." Regensburg : Universitätsbibliothek Regensburg, 2017. http://d-nb.info/1143948939/34.
Full textAkimkin, Valerij [Verfasser]. "Untersuchungen zum Nachweis enteraler Viren in Putenbeständen mittels Transmissionselektronenmikroskopie und Polymerase-Kettenreaktion / Valerij Akimkin." Berlin : Freie Universität Berlin, 2013. http://d-nb.info/1038694914/34.
Full textNiermann, Tore. "Mikrostrukturelle Untersuchungen an Mangan-dotiertem Galliumnitrid mittels fortgeschrittener Methoden der hochauflösenden und analytischen Transmissionselektronenmikroskopie." [S.l.] : [s.n.], 2006. http://webdoc.sub.gwdg.de/diss/2006/niermann.
Full textDietrich, Jens [Verfasser], and Christian [Akademischer Betreuer] Boit. "Mikrostrukturanalyse von Cu(In,Ga)Se 2-Dünnschichtsolarzellen mittels Transmissionselektronenmikroskopie / Jens Dietrich. Betreuer: Christian Boit." Berlin : Universitätsbibliothek der Technischen Universität Berlin, 2013. http://d-nb.info/1031075054/34.
Full textSCHADE, MARTIN [Verfasser], Hartmut S. [Akademischer Betreuer] Leipner, Jörg [Akademischer Betreuer] Schilling, and Joachim [Akademischer Betreuer] Meyer. "Analytische Transmissionselektronenmikroskopie an polymorphen Siliziumnanostrukturen / Martin Schade. Betreuer: Hartmut S. Leipner ; Jörg Schilling ; Joachim Meyer." Halle, Saale : Universitäts- und Landesbibliothek Sachsen-Anhalt, 2013. http://d-nb.info/1045604178/34.
Full textGroß, Hendrik [Verfasser], Lorenz [Akademischer Betreuer] Kienle, and Rainer [Gutachter] Adelung. "Strukturelle Charakterisierung Chromchalkogenid-basierter Thermoelektrika mittels Transmissionselektronenmikroskopie / Hendrik Groß ; Gutachter: Rainer Adelung ; Betreuer: Lorenz Kienle." Kiel : Universitätsbibliothek Kiel, 2021. http://d-nb.info/1236571924/34.
Full textSmedts, Ellen. "Beurteilung von nativen und aufgetauten Spermatozoen fertiler und subfertiler Hengste mit Hilfe der Phasenkontrast- und Transmissionselektronenmikroskopie." Doctoral thesis, Universitätsbibliothek Leipzig, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-87838.
Full textEvaluation of fresh and frozen-thawed semen samples of fertile and subfertile stallions by light microscopy and transmission electron microscopy. Institut of Pathology of the Faculty of Veterinary Medicine, University of Leipzig Reproduktionsmedizinische Einheit der Kliniken der Tierärztlichen Hochschule Hannover In this study the ultrastructure of fresh and frozen-thawed semen samples of 50 stallions from the National Stud of Lower Saxony (Celle, Germany) were evaluated by light microscopy and transmission electron microscopy (TEM). Three ejaculates of each stallion were available for the motility analysis and the morphological analysis by lightmicroscopy after fixation in formol citrate. Based on the fertility data, the ejaculates of 12 stallions (3 fertile stallions, 3 subfertile stallions and 6 stallions of average fertility) were selected for the morphological analysis by TEM. The native samples and one frozen-thawed sample from these stallions were prepared for the TEM at the Institute of Pathology of the Faculty of Veterinary Medicine, Uni-versity of Leipzig. The sperm cells were washed and the seminal plasma from the native samples and the diluents of the frozen-thawed samples were replaced by a 5%-glutaraldehyde solution in a 0,1 M cacodylate buffer pH 7,2. The fixative was removed, the pellet was washed again and mixed with gelatin. The sperm rich fraction in the gelatin mass was excised and stored in glutaraldehyde. A second fixation in OsO4 was followed by a dehydratation in ethanol and a polymerization phase in epon. After 5 days of polymerization the starred samples were used for semi- and ultratight cuts. The latter were placed on a copper grid, contrasted with uranyl acetate and lead citrate and analyzed with the transmission electron micro-scope (EM 900) by 80 kV. In the fresh samples, 360 sperm cells were examined per stallion, whereas in the frozen-thawed samples only 120 sperm cells per stallion were evaluated. The microscopic pictures were of a high quality. However, the sperm plasma membrane showed some fixation artifacts. In the thawed samples a lower contrast was noticed than in the fresh samples. The sperm cells in the frozen-thawed samples showed an increase in acrosome defects, acrosome reactions, damage of the cell plasma membrane, mitochondria, fibrous sheet and outer dense fibers. The latter defect was associated with a decrease in proximal and distal cytoplasmatic droplets. Swollen acrosomes with a lower matrix density and a bright mitochondrial matrix were typically present in the cryopreserved samples. The ultrastructural defects in these samples, examined by TEM, have led to the development of a standard evaluation protocol with the most common sperm defects in stallion semen. TEM is an expensive and time consuming technique, which cannot be used to obtain quantitative results, but is considered as an accurate method for the qualitative examination of semen samples in cases of unexplained subfertility. TEM can especially be recommended for the diagnosis of nuclear (nuclear malformations and pouches) and acrosomal defects (acrosome deformations, acrosome vacuoles, detached acrosomes and acrosome reactions), mitochondrial (mitochondrial sheet defects, mitochondrial proliferation, decrease in mitochondrial matrix density) and axonema malformations (anormal position or quantity of microtubules and fibrous sheet or outer dense fibers defects) and the detection of immature sperm cells in ejaculates. The results of this study state that TEM can be useful for the evaluation of both fresh and frozen-thawed semen samples. Compared to the light microscopic evaluation of stallion sperm, the TEM images give more precise information because of their higher magnification rate and the ability to reveal internal sperm structures. However, light microscopy remains the best method to detect sperm neck defects, deformed tailes and sperm cells with multiple heads or tails
Wirch, Nelly Verfasser], Thomas [Akademischer Betreuer] Weirich, and Joachim [Akademischer Betreuer] [Mayer. "Charakterisierung funktioneller Nanopartikel und ihrer Einbettung in Polymerfasern mittels Transmissionselektronenmikroskopie / Nelly Wirch ; Thomas Weirich, Joachim Mayer." Aachen : Universitätsbibliothek der RWTH Aachen, 2018. http://d-nb.info/1187346683/34.
Full textDries, Manuel Rainer [Verfasser], and D. [Akademischer Betreuer] Gerthsen. "Experimentelle und theoretische Untersuchungen zum Hilbert-Phasenkontrast in der Transmissionselektronenmikroskopie / Manuel Rainer Dries. Betreuer: D. Gerthsen." Karlsruhe : KIT-Bibliothek, 2015. http://d-nb.info/1078957789/34.
Full textWirch, Nelly [Verfasser], Thomas Akademischer Betreuer] Weirich, and Joachim [Akademischer Betreuer] [Mayer. "Charakterisierung funktioneller Nanopartikel und ihrer Einbettung in Polymerfasern mittels Transmissionselektronenmikroskopie / Nelly Wirch ; Thomas Weirich, Joachim Mayer." Aachen : Universitätsbibliothek der RWTH Aachen, 2018. http://d-nb.info/1187346683/34.
Full textStraskraba, Susanne [Verfasser], Claudia [Gutachter] Büchel, and Bruno [Gutachter] Streit. "Transmissionselektronenmikroskopie von Nanomaterialien sowie Untersuchungen zu deren Wirkung auf Mikroalgen / Susanne Straskraba ; Gutachter: Claudia Büchel, Bruno Streit." Frankfurt am Main : Universitätsbibliothek Johann Christian Senckenberg, 2020. http://d-nb.info/1210555719/34.
Full textKobler, Aaron [Verfasser], Horst [Akademischer Betreuer] Hahn, and Ute [Akademischer Betreuer] Kolb. "Untersuchung der Deformationsmechanismen in nanostrukturierten Metallen und Legierungen mit Transmissionselektronenmikroskopie / Aaron Kobler. Betreuer: Horst Hahn ; Ute Kolb." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2015. http://d-nb.info/1112332693/34.
Full textMühle, Uwe [Verfasser], David [Akademischer Betreuer] Rafaja, David [Gutachter] Rafaja, Hannes [Gutachter] Lichte, and Ehrenfried [Gutachter] Zschech. "Spezielle Anwendungen der Transmissionselektronenmikroskopie in der Siliziumhalbleiterindustrie / Uwe Mühle ; Gutachter: David Rafaja, Hannes Lichte, Ehrenfried Zschech ; Betreuer: David Rafaja." Freiberg : Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2015. http://d-nb.info/122069892X/34.
Full textSeyring, Martin [Verfasser], Markus [Akademischer Betreuer] Rettenmayr, Falko [Akademischer Betreuer] Langenhorst, and Gerhard [Akademischer Betreuer] Wilde. "Charakterisierung von Korngrenzen und Phasen in nanokristallinen Materialien mit Transmissionselektronenmikroskopie / Martin Seyring. Gutachter: Markus Rettenmayr ; Falko Langenhorst ; Gerhard Wilde." Jena : Thüringer Universitäts- und Landesbibliothek Jena, 2014. http://d-nb.info/1062536207/34.
Full textVieweg, Benito Fernando [Verfasser], and Erdmann [Akademischer Betreuer] Spiecker. "Entwicklung und Anwendung neuartiger Präparationsverfahren für die Transmissionselektronenmikroskopie von dünnen Schichten, Nanopartikeln und Kristalldefekten / Benito Fernando Vieweg. Betreuer: Erdmann Spiecker." Erlangen : Universitätsbibliothek der Universität Erlangen-Nürnberg, 2012. http://d-nb.info/1025182782/34.
Full textRiedl, Thomas. "La0,7Sr0,3MnO3-Dünnschichten auf SrTiO3 (0 0 1)-Substrat: Struktur und Mn-Wertigkeit." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1211277073076-72652.
Full textMikat, Jürgen E. R. "Optische und schwingungsspektroskopische Hochdruckuntersuchungen von Ladungsträgereigenschaften in herkömmlich und nach der Template-Methode synthetisierten leitfähigen Polypyrrolschichten." Phd thesis, Universität Potsdam, 2001. http://opus.kobv.de/ubp/volltexte/2005/23/.
Full textDurch spezifische Synthesemethoden lassen sich unterschiedliche Strukturen in der polymeren Probe induzieren, die sich durch den Anteil an hochgeordneten Polymerketten unterscheiden. Die gezielte Veränderung dieser Strukturen durch Druckexperimente ermöglicht das Studium des Einflusses der Synthesemethoden auf die Ladungsträgereigenschaften. Für diese Studien wurden herkömmlich synthetisierte Polypyrrol-Filme und Filme, die sich aus Polypyrrol-Nanoröhren zusammensetzen (Synthese in Kernspur-membranen, "Template-Synthese") bei ansonsten gleichen Syntheseparametern untersucht. Raman- und Infrarotspektroskopie sowie UV-Vis-NIR-Absorptionsspektroskopie, die jeweils für die Hochdruckmethodik adaptiert wurden, dienten der Charakterisierung der Proben. Zusätzlich wurden temperatur- und druckabhängige Messungen des elektrischen Widerstands an den Template-Proben durchgeführt. Die Morphologie template-synthetisierter Polypyrrol-Nanoröhren und die filmbildenden Eigenschaften sowie der mögliche Aufbau von Schichtarchitekturen wurden mit transmissions- und rasterelektronenmikroskopischen Techniken untersucht.
Die aus den Hochdruckexperimenten gewonnenen Daten werden in der Arbeit im Hinblick auf die Stabilität der Ladungsträger interpretiert. Im Ergebnis bewirkt die Druckerhöhung eine Dissoziation der Bipolaronen in den untersuchten Proben. Das Ladungsträger-gleichgewicht verschiebt sich dadurch mit steigendem Druck zu Zuständen mit höherem Anteil an polaronischen Ladungsträgern. Die Template-Synthese bewirkt gegenüber herkömmlich synthetisierten Proben einen höheren Anteil an Polaronen bereits bei Normaldruck, und eine Lage des Systems näher bei einem Isolator-Metall-Übergang. Die Dissoziationsrate der Bipolaronen ist für Template- und herkömmlich synthetisierte Proben vergleichbar groß und unabhängig vom Initialzustand nach der Synthese.
Dieses Verhalten der Ladungsträger wird weitergehend im Rahmen eines Modells untersucht, bei dem der Einfluß benachbarter Polymerketten und der Dotandionen berücksichtigt wird. Dementsprechend können sich die Wellenfunktionen der Ladungsträger unter bestimmten Bedingungen auch auf benachbarte Ketten erstrecken (transversale Polaronen bzw. Bipolaronen). Eine solche Ausdehnung der Wellenfunktionen unter Mitwirkung der Dotandionen wurde in den untersuchten Proben nicht festgestellt. Die Wellenfunktionen der Ladungsträger besitzen demnach hauptsächlich Komponenten entlang der Polymerkette (longitudinale Polaronen bzw. Bipolaronen). Aus der Änderungsrate druckabhängiger spektraler Charakteristiken lassen sich Aussagen über den Ordnungszustand der Probe ableiten.
Diese auf experimentellem Wege gefundenen Ergebnisse liefern somit Hinweise für die bisher kontrovers diskutierte Koexistenz der beiden Ladungsträgerarten Polaronen und Bipolaronen und die Größe ihrer jeweiligen Bindungsenergien. Druckerhöhung und Template-Synthese bewirken analoge Änderungen der Polymerstruktur. Sowohl höherer Druck wie auch die Template-Synthese lassen sich mit einem höheren Ordnungsgrad in den Template-Proben korrelieren.
Der Ladungstransport in den Proben kann durch ein Mott Variable Range Hopping-Modell mit druckabhängiger charakteristischer Dimension beschrieben werden. Die Erhöhung des Drucks bewirkt einen Anstieg der Dimension, eine bessere Überlappung der Wellenfunktionen der Ladungsträger und eine Vergrößerung der Lokalisierungslänge der Ladungsträger. Die druckinduzierte Dissoziation der Bipolaronen beeinflußt den Ladungstransport zusätzlich durch Erhöhung der Anzahl unabhängiger Ladungsträger und verbessert diesen aufgrund stärkerer Überlappung der Wellenfunktionen. Template-Proben niedriger Synthesetemperatur zeigen bei Normaldruck eine höhere Dimension des Mott Variable Range Hoppings und eine größere Lokalisierungslänge gegenüber bei Raumtemperatur synthetisierten Proben. Kürzere Synthesezeiten bewirken einen Anstieg der Dimension bei Normaldruck und eine Verschiebung des Dimensionscrossovers zu niedrigeren Temperaturen. Template-Proben kurzer Synthesezeit zeigen geringere druckinduzierte Änderungen als solche mit langer Synthesezeit. Es wurde ein kontinuierliches Ordnungsmodell der Polypyrrol-Nanoröhren entwickelt, das dieses Verhalten beschreibt.
Die Morphologie und die mechanischen Eigenschaften der Nanoröhren werden durch spezifische Syntheseparameter, wie Temperatur und Dauer, beeinflußt und können mit Transmissions- und Rasterelektronenmikroskopie beobachtet werden. Die filmbildenden Eigenschaften der Röhren hängen stark von diesen mechanischen Eigenschaften ab. Die Struktur der Filme kann dabei von einer unregelmäßigen Anordnung der Röhren bis zu nahezu parallel ausgerichteten Röhren variieren. Es wurden Möglichkeiten untersucht, die Röhren in den Filmen zu orientieren und aus diesen Filmen durch Schichtung makroskopische Architekturen mit einem hohen Grad an orientierten Röhren aufzubauen. Solche Architekturen können für verschiedene Anwendungen, z.B. in elektronischen Bauteilen oder mikroskopischen Bioreaktoren, von Interesse sein.
Chemically doped polypyrrole is a model substance for conducting polymers with non-degenerate ground state. The electrical transport behaviour in doped polypyrrole is determined by localised charge carriers, polarons and bipolarons, respectively. A strong interaction between the structure of the polymer chain and the properties of the carriers exists. In this work the applicability of the combination of high pressure techniques with spectroscopy in the visible spectral range is demonstrated to improve the understanding of the relationship between the molecular and supramolecular structure and the electronic and optical properties.
The use of specific synthesis methods allows the induction of different structures in the polymeric sample. These structures possess different amounts of highly ordered polymer chains. High pressure experiments are a suitable method to influence the structures in a controlled manner. In this way the effect of the different synthesis methods on the charge carrier properties can be studied. For these investigations polypyrrole films synthesised by ordinary chemical synthesis and films build up of template synthesised polypyrrole nanotubules, respectively, were fabricated under the same chemical synthesis conditions. The characterisation of the samples was carried out by Raman and infrared spectroscopy as well as optical absorption spectroscopy. All spectroscopic methods were adapted for high pressure techniques. Additionally, temperature and pressure dependent measurements of the electrical resistance were performed on the template synthesised samples. The morphology of polypyrrole nanotubules and films consisting of nanotubules as well as architectures built up from these films were examined by transmission and scanning electron microscopy.
The data obtained from the high pressure experiments are interpreted in view of the stability of the charge carriers. One result is the dissoziation of bipolarons upon pressure increase in the samples under investigation with increasing pressure. The charge carrier equilibrium is shifted to states with larger amount of polarons. Template synthesis, compared with ordinarily synthesised samples, results in a larger amount of polarons at ambient pressure and a position of the samples closer to an insulator-metal transition. The dissoziation rate of bipolarons in template and ordinary synthesised samples is comparable and independent of the initial state after completed synthesis procedure.
This behaviour of the charge carriers is further investigated in the frame of a model which takes the influence of neighbouring polymer chains and of dopant ions into considerations. According to this model, the wave functions of the charge carriers are also allowed to extend on neighboured chains under certain conditions (transverse polarons or bipolarons, respectively). Such an expansion of the wave functions where dopant ions act as mediating bridges of lower potential cannot be observed in the samples under investigation. Hence, the wave functions of the charge carriers contain mainly components along the polymer chain (longitudinal polarons or bipolarons, respectively). From the alteration rate of pressure dependent spectral characteristics information can be gained on the state of order in the samples.
These experimental results deliver hints for the up to now controversial discussion on the coexistence of the charge carrier species polarons and bipolarons and the magnitude of their binding energies. Pressure increase and template synthesis yield analogous changes of the polymer structure. High pressure as well as template synthesis can be correlated with a higher degree of order in the samples.
The charge carrier transport in the samples can be described by a Mott Variable Range Hopping model with a pressure dependent characteristic dimension. The increase of pressure results in an increasing dimension, a larger overlap of the wave function of the charge carriers and an increase of their localisation length. Additionally, pressure induced dissoziation of bipolarons improves the charge carrier transport by increasing the amount of independent charge carriers and larger overlap of the wave functions. Template synthesised samples prepared at lower synthesis temperature show a higher dimension of the Mott Variable Range Hopping and a larger localisation length than samples synthesised at room temperature. Shorter synthesis time results in an increase of the characteristic dimension at ambient pressure and a shift of the dimensional crossover to lower temperatures. Also, these samples show smaller pressure induced changes compared to samples with longer synthesis time. A model is developed describing this behaviour in the frame of a continuous order change in polypyrrole nanotubules.
The morphology and the mechanical properties of the template synthesised nanotubules are influenced by specific synthesis parameters, e.g. temperature and duration, as can be observed by transmission and scanning electron microscopy. The resulting films formed by the tubules strongly depend on these mechanical properties. The structure of the films can vary between disordered arrangement and almost parallel orientation of the tubules. The possibilities for orienting of the individual tubules in films and for building macroscopic architectures by subsequent stacking of those films were investigated. Such architectures are interesting from an application point of view e.g. in electronic devices and microscopic bioreactors.
Thiel, Karsten. "Strukturelle Untersuchung der amorph-kristallinen Grenzfläche mittels quantitativer hochauflösender Transmissionselektronenmikroskopie an den Systemen a-Si-c-Si und a-Ge-c-Si." [S.l.] : [s.n.], 2006. http://webdoc.sub.gwdg.de/diss/2006/thiel.
Full textFrank, Kristian [Verfasser], Andreas [Akademischer Betreuer] Rosenauer, and Jens [Akademischer Betreuer] Falta. "Untersuchung von Katalysatoren auf Gold/TiO2-Basis und optoelektronischen Halbleitern mittels Transmissionselektronenmikroskopie und Tomographie / Kristian Frank. Gutachter: Andreas Rosenauer ; Jens Falta. Betreuer: Andreas Rosenauer." Bremen : Staats- und Universitätsbibliothek Bremen, 2014. http://d-nb.info/107222657X/34.
Full textDömer, Holger. "Hochgeschwindigkeits-Transmissionselektronenmikroskopie zur zeitaufgelösten Untersuchung der Laserablation dünner Metallfolien extreme Spannungen, hydrodynamische Instabilitäten, Phasenexplosion und hochionisierte, transiente Plasmen nach Einwirkung eines kurzen bzw. ultrakurzen Laserpulses /." [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=97187297X.
Full textRiedl, Thomas. "La0,7Sr0,3MnO3-Dünnschichten auf SrTiO3 (0 0 1)-Substrat: Struktur und Mn-Wertigkeit." Doctoral thesis, Technische Universität Dresden, 2007. https://tud.qucosa.de/id/qucosa%3A23816.
Full textSchewski, Robert. "Transmission electron microscopic investigation of the growth of group III sesquioxides Ga2O3." Doctoral thesis, Humboldt-Universität zu Berlin, 2019. http://dx.doi.org/10.18452/19789.
Full textIn this work we study the basic growth processes of epitaxial Ga2O3 films, by means of transmission electron microscopy. We investigate the heteroepitaxial growth of thin layers Ga2O3 on the (0001) plane of sapphire grown by molecular beam epitaxy (MBE), pulsed laser deposition (PLD) and metal organic vapor phase epitaxy (MOVPE). Furthermore, we will focus on the homoepitaxial growth on the (100) plane by MOVPE. Beside the peculiarities of the layer growth dependence on different metal organic precursors and oxygen sources, we investigate the influence of typical growth parameters (i.e. growth temperature, growth-rate, chamber pressure and miscut angle of the substrate) on the layer morphology. Incase of heteroepitaxial growth of β-Ga2O3 on (0001) plane of sapphire, independent of the growth method, the formation of a 3 monolayer thick α-Ga2O3 layer is observed, which is stabilized through strain, as a result of the lattice mismatch between sapphire and α-Ga2O3. In case of homoepitaxial growth by MOVPE on (100) oriented β-Ga2O3, the crystalline quality of the grown layer strongly depends on the used precursor (tri-methyl-gallium (TMGa) or tri-ethyl-gallium (TEGa) as metal precursor and H2O or pure oxygen as oxidant) and the chemical processes on the surface, respectively. Further on is the crystalline perfection of homoepitaxial layers grown by MOVPE on (100) oriented β-Ga2O3 substrates strongly dependent on the miscut-angle of the substrates. Layer grown on substrate with a small miscut-angle (< 2°) show high amount of twin lamella. These twin lamella are a result of a possible double positioning mechanism of ad-atoms on the growth surface. By introducing appropriate miscut-angles of the substrate it is possible to suppress the formation of these twin lamellae, and enable step flow growth. By applying a rate equation approach, describing the competing processes of incorporation of ad-atoms at kink sites or nucleation and growth of two dimensional island, it is possible to quantitatively reproduce the experimentally observed twin lamella densities and to determine a surface diffusion coefficient of the ad-atoms. Furthermore, in case of the alloy system (InxGa1-x)2O3, it is shown that indium can act as an surfactant, by increasing the surface diffusion.
Pavlovich, Tatiana. "Analyse der Subgefügeentwicklung kubischer Metalle bei hohen Umformgraden auf der Grundlage von Röntgenbeugung und Elektronenmikroskopie." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2009. http://nbn-resolving.de/urn:nbn:de:bsz:105-2370866.
Full textLox, Josephine F. L., Zhiya Dang, Anh Mai Lê, Eileen Hollinger, and Vladimir Lesnyak. "Colloidal Cu–Zn–In–S-Based Disk-Shaped Nanocookies." American Chemical Association, 2019. https://tud.qucosa.de/id/qucosa%3A74324.
Full textWouters, Charlotte. "Impact of order and disorder on phase formation in (InxGa1-x)2O3 investigated by transmission electron microscopy." Doctoral thesis, Humboldt-Universität zu Berlin, 2021. http://dx.doi.org/10.18452/22883.
Full textWe investigate the phase formation in (InxGa1-x)2O3 solid solutions experimentally by means of transmission electron microscopy (TEM) and with computational support using cluster expansion. In the case of epitaxial growth on crystalline substrates, we find strong ordering on the cation sublattices of (InxGa1-x)2O3, energetically driven by the tendency of In and Ga to each assume their preferred coordination environment. Based on this experimental finding, we modify the model of the ideal mixture by considering the configurational entropy on the respective cation sublattices with different coordination separately in order to calculate it realistically. The resulting phase diagram is characterized by narrow thermodynamically stable ranges for each phase, while wide composition ranges of metastable compounds are predicted, which can be achieved at temperatures typical for epitaxy: the monoclinic phase is metastable in the composition range x<0.5, the hexagonal phase for 0.55
Linck, Martin. "Off-axis Holografie im aberrationskorrigierten Transmissionselektronenmikroskop." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-38972.
Full textOff-axis electron holography in a transmission electron microscope (TEM) allows reconstructing the complex object exit-wave quantitatively with atomic resolution. Analyzing the phase shift of this wave gives access to the atomic species and enables counting the number of atoms in projection direction as well as determining atom positions. Therefore, a TEM is a very powerful measuring device for quantitative analysis of smallest structures down to the atomic scale beyond simple microscopic imaging. The procedure of the recording of a high-resolution electron hologram, its reconstruction, and after numerical aberration correction finally ending up with the object-exit wave, is quite comprehensive and partially susceptible to artifacts. This work shows how to manage this procedure in order to obtain an interpretable object exit-wave, which is free of artifacts. In instrumentation within the last decade aberration correctors have revolutionized high-resolution electron microscopy. Also off-axis holography can benefit from this electron optical add-on module. Besides the exploration of each improvement, in particular the phase detection limit, this work demonstrates, how to optimize the Cs-corrected TEM in order to get best possible results for quantitative object analysis. Two application examples show experimental results of electron holography with Cs-corrected microscopes. For the investigation of ferroelectric nanolayers, the unique possibilities of the holographic evaluation together with the strongly improved signal resolution turn out to be very useful when determining the ferroelectric polarization. The object wave reconstruction of the grain boundary in a gold film demonstrates further improvements for holography, when additionally using a new electron gun with improved brightness. Single gold atoms become measurable with a signal-noise-ratio of about 10 in amplitude and phase
Müller, Andreas, Martin Neukam, Anna Ivanova, Anke Sönmez, Carla Münster, Susanne Kretschmar, Yannis Kalaidzidis, Thomas Kurth, Jean-Marc Verbavatz, and Michele Solimena. "A Global Approach for Quantitative Super Resolution and Electron Microscopy on Cryo and Epoxy Sections Using Self-labeling Protein Tags." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-221826.
Full textStolyarchuk, Natalia. "Transmission electron microscopy study of polarity control in III-N films grown on sapphire substrates." Doctoral thesis, Humboldt-Universität zu Berlin, 2018. http://dx.doi.org/10.18452/18791.
Full textPolarity is a critical issue for III-nitrides material system that has an impact on the quality and properties of epitaxial films and the performance of nitride-based devices. But the understanding of the elementary mechanisms that are responsible for establishing metal or nitrogen polarity of the films grown on nonpolar substrate is lacking. The existing concepts are based on empirical observations and contain ambiguous results. One of the main reasons for that is the lack of precise characterization tools, allowing localized determination of polarity and atomic structure of layers, at the time, when main concepts for polarity control were established. In this work we develop a concept of polarity control in AlN and GaN layers grown by metalorganic vapor phase epitaxy (MOVPE) on sapphire substrates. The polarity of the layers is studied by aberration corrected HRTEM and high resolution high-angle annular dark field (HAADF) scanning TEM. The analysis of the experimental investigations yields the following principal results about: (i) the mechanism that governs polarity selection; (ii) the relation between sapphire surface nitridation and Al-polar domains in N-polar AlN films; (iii) the possibility of controlled switching the layers polarity from N to Al by oxygen annealing. The understanding of these mechanisms by which polarity is controlled opens up the possibility for polarity engineering in nitride films and can give a clue to understanding polarity control in other material systems (e.g. oxides).
La polarité est une question critique pour le système de matériaux III-nitrures, qui a un impact sur la qualité des films épitaxies et la performance des dispositifs à base de nitrure. Mais la compréhension des mécanismes élémentaires responsables de l'établissement de la polarité N ou métallique des films sur le substrat non-polaire manque. Les concepts existants sont basés sur des observations empiriques et contiennent des résultats ambigus. Une des raisons principales est le manque d'outils analytiques, permettant la détermination localisée de la polarité et de la structure atomique des couches à l'époque, lorsque les concepts de contrôle de la polarité ont été établis. Dans ce travail, nous développons un concept de contrôle de la polarité dans les couches AlN et GaN épitaxies sur substrat de saphir par EPVOM. La polarité des couches est étudiée par microscopie électronique en transmission (MET) haute résolution corrigée des aberrations et par microscope électronique à balayage en transmission en champ sombre (HAADF-STEM). L'analyse des investigations expérimentales donne les principaux résultats suivants : (i) le mécanisme qui régit la sélection de la polarité; (ii) la relation entre la nitruration de la surface et les domaines de polarité Al dans les films d'AlN N-polaire; (iii) possibilité d’inverser la polarité N de films d’AlN de polarité mixte en introduisant un recuit sous oxygène. La compréhension de mécanisme par lequel la polarité est contrôlée ouvre les possibilités d'une ingénierie de polarité dans les films de nitrure et peut donner une idée de la compréhension du contrôle de la polarité dans d'autres systèmes de matériaux (par exemple, les oxydes).
Pavlovich, Tatiana. "Analyse der Subgefügeentwicklung kubischer Metalle bei hohen Umformgraden auf der Grundlage von Röntgenbeugung und Elektronenmikroskopie." Doctoral thesis, TU Bergakademie Freiberg, 2007. https://tubaf.qucosa.de/id/qucosa%3A22632.
Full textGonzalez-Martinez, I. G., A. Bachmatiuk, V. Bezugly, J. Kunstmann, T. Gemming, Z. Liu, G. Cuniberti, and M. H. Rümmeli. "Electron-beam induced synthesis of nanostructures: a review." Royal Society of Chemistry, 2016. https://tud.qucosa.de/id/qucosa%3A36362.
Full textSmedts, Ellen [Verfasser], Heinz-Adolf [Akademischer Betreuer] Schoon, Harald [Akademischer Betreuer] Sieme, and Heinrich [Gutachter] Bollwein. "Beurteilung von nativen und aufgetauten Spermatozoen fertiler und subfertiler Hengste mit Hilfe der Phasenkontrast- und Transmissionselektronenmikroskopie : Beurteilung von nativen und aufgetauten Spermatozoen fertiler und subfertiler Hengste mit Hilfe der Phasenkontrast- undTransmissionselektronenmikroskopie / Ellen Smedts ; Gutachter: Heinrich Bollwein ; Heinz-Adolf Schoon, Harald Sieme." Leipzig : Universitätsbibliothek Leipzig, 2012. http://d-nb.info/1238076882/34.
Full textMotylenko, Mykhaylo. "Beitrag zur Analyse von Disklinationsstrukturen in plastisch verformten Metallen." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2011. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-67416.
Full textFalke, Uwe. "Anwendungen der Elektronen-Energieverlust-Spektroskopie in der Materialwissenschaft." [S.l. : s.n.], 1998. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB10324550.
Full textKirsch, Jasmin, Sandra Pötschke, Sabine Basche, Christian Hannig, William H. Bowen, Matthias Hannig, Stefan Rupf, Simone Trautmann, and Natalia Umanskaya. "Enzymology and Ultrastructure of the in situ Pellicle in Caries-Active and Caries-Inactive Patients." Karger, 2017. https://tud.qucosa.de/id/qucosa%3A70611.
Full textSpringsguth, Hans Christopher. "Mechanismen und Bedeutung der aktivierten Apoptosekaskade in humanen Spermatozoen." Doctoral thesis, Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-192660.
Full textSchaumberg, Christian Alexander. "Mechanismen der Laserablation zur Synthese nanoskopischer Kolloide." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät, 2016. http://dx.doi.org/10.18452/17482.
Full textThe synthesis of colloidal nanoparticles has become a major topic in recent years. The pulsed laser ablation in liquids poses an alternative to the common wet-chemical approaches. Key features of the pulsed laser ablation in liquids are its simple setup, its versatility, and the possibility to generate surfactant-free colloidal nanoparticles. A further development of this technique is the use of suspended powders instead of bulk targets. This leads to higher productivities and even new materials. Although the generation of colloids by irradiating a suspension is straight forward, the underlying mechanisms of the size reduction from micrometer to nanometer sized particles appear to be quite complex. In order to reveal the mechanism a chemical approach was chosen. Hence, various copper compounds (Cu2C2, Cu5Si, Cu3N, Cu(N3)2, Cu3P, Cu2O, CuO, Cu2S, CuS and CuI) were used as a model system in order to investigate the impact of the leaving group on the ablation process. The generated nanoparticles were characterized with analytical transmission electron microscopy. These investigations clearly show that there are two distinct mechanisms involved in nanoparticle formation. The laser irradiation of precursors like CuO and Cu3N results in the formation of metallic copper nanoparticles. In the generated plasma copper atoms nucleate and form small primary particles. These particles later coalesce to larger secondary particles. In contrast to this reductive ablation, the irradiation of CuI follows a fragmentation mechanism. Here, the absorbed power of the laser beam does not produce a plasma but introduces thermal stress leading to fragmentation of the crystal while the chemical composition is preserved. The question which mechanism is predominant is of utmost importance as the chemical composition of the nanoparticles depends on the formation process. This is discussed on the example of the synthesis of Bi2Te3 nanoparticles, which can be used in thermoelectric applications.
Liu, Tian-Yu. "Transmission electron microscopy studies of GaN/gamma-LiAlO 2 heterostructures." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2005. http://dx.doi.org/10.18452/15278.
Full textIn this work the structure of (1-100)M-plane GaN epitaxially grown on gamma-LiAlO2(100) by using plasmaassisted molecular beam epitaxy (PAMBE) is studied. The heteroepitaxial alignment and the microstructure of M-plane GaN as well as the defect formation in the layer are systematically investigated by using transmission electron microscopy (TEM). The gamma-LiALO2 substrate reacts under irradiation of high-energy electrons in the TEM (200-300 keV).The material looses its original crystalline structure during this process undergoing irradiation damage followed by a phase transformation as it is verified by a series of selected area diffraction patterns taken under constant electron dose. The result is a structural phase transformation from the tetragonal gamma to the trigonal alpha phase. The atomic interface structure of epitaxially grown hexagonal alpha-GaN(1-100) layers on tetragonal gamma-LiAlO2 (100) substrates is investigated by means of HRTEM. The novel epitaxial orientation relationship verified by electron diffraction is given by (1-100)GaN parallel to (100)gamma-LiAlO2 and [11-20]GaN parallel to [001]gamma-LiAlO2. The defect structure of M-plane GaN epilayers grown on gamma-LiAlO2(100) substrates is different to that of C-plane GaN. Our detailed TEM studies reveal that the M-plane layers mainly contain intrinsic I1 and I2 and extrinsic E basal plane stacking faults. The dominant I2 stacking fault has no out-of-plane displacement vector component and is thus not qualified for epitaxial strain relief along the [11-20] axis. Beyond this, a complex type of planar defect is detected in the (10-10) prism plane which is inclined with respect to the interface. The study of nucleation samples shows that the surface morphology is directly correlated to the generation of the dominant planar defects. Atomic steps along the [001] direction in the gamma-LiAlO2 substrate result in the formation of basal plane stacking faults I2.
Mertinat, Markus [Verfasser]. "Temperaturabhängige Strukturuntersuchungen an FeCr2S4, V2O3 und VO2 im Transmissionselektronenmikroskop / Markus Mertinat." Aachen : Shaker, 2004. http://d-nb.info/1170545246/34.
Full textSickmann, Jan. "Ortsaufgelöste Messung der Gitterverspannungen in Halbleitern mittels Dunkelfeld off-axis Elektronenholographie." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-160646.
Full textDark-field off-axis electron holography (DFH) in a transmission electron microscope is based on the interference of a diffracted wave emanating from adjacent strained and unstrained sample areas to form a dark-field hologram, from which the phase of the diffracted wave can be reconstructed. Since the gradient of the phase parallel to the diffraction vector yields the lattice strain in this direction, a two-dimensional strain map can be derived. Therefore, DFH is considered to be a promising technique for strain metrology by semiconductor industry, especially for local strain measurements in the transistor channel. In particular, DFH offers better lateral resolution than scanning TEM-techniques based on electron diffraction with small focused electron probe like nano-beam diffraction. However, DFH is not yet available as a standard technique for strain metrology. Research is still needed to apply the method to complex devices. Using the example of a strained cosine lattice the phase modulation due to lattice distortions is discussed. In addition, modulation of the diffracted wave is approximated in two-beam diffraction condition. Adjustments of DFH in the TEM provide strain measurements with 3...5 nm lateral resolution at 200 nm field of view or 8...10 nm lateral resolution at 800 nm field of view. During recording and reconstruction of dark-field holograms several artifacts appear, for instance Fresnel diffraction, defective detector pixels, distortions of projective lenses or detector optics. Since they limit strain evaluation, suitable methods to either avoid or correct these artifacts are discussed. Sample preparation with focused ion beam (FIB) causes surface damage. Comparing DFH results with finite-element simulations reveals a deviation of 10% between simulation and experiment at 120...160 nm sample thickness due to surface relaxation. FIB-induced thickness variations (curtaining) lead to comparable deviations. Applicability of DFH for strain metrology is analyzed on several modern device structures. Strain measurements of SiGe-layers on Si-substrate correspond quite well with an analytic model. A residual deviation of 10% can be explained by surface relaxation close to the SiGe/Si-interface. Transistors strained by SiGe-source/drain serve as test objects for a comparison of DFH with nano-beam diffraction. Though both techniques reveal identical results, DFH is able to map the complete two-dimensional strain field, whereas nano-beam diffraction can only provide single line-scans. Strain mapping in silicon-on-insulator (SOI) is limited by the different crystal orientation (miscut) between the SOI layer and the Si-substrate, which serves as reference. Strain values in the SOI show an off-set of 0.2% in comparison to the unstrained Si-substrate. The miscut between SOI and Si-substrate is estimated to 0.3°. In transistor devices with tensile stress overlayers DFH is able to measure +0.3% tensile strain in excellent agreement with finite-element simulations. In devices with compressive overlayers and SiGe-source/drain a strain value of only -(0.1+/-0.05)% can be determined in the transistor channel 5nm beneath the gate oxide
Grosse, Corinna. "Structural and electrical characterization of novel layered intergrowth compounds." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät, 2016. http://dx.doi.org/10.18452/17432.
Full textThe investigated ferecrystals are novel layered intergrowth compounds consisting of m monolayers of niobium diselenide (NbSe2) stacked repeatedly with n atomic bilayers of lead selenide (PbSe) or tin selenide (SnSe). Bulk NbSe2 is a layered compound showing superconductivity. Due to their artificially atomic-scale layered structure, which is tunable on the atomic scale, ferecrystals can serve as model systems for layered superconductors. In this study, their structural and electrical properties are investigated. Using transmission electron microscopy their turbostratically disordered, nanocrystalline structure is revealed. The atomic structure within the individual layers is similar as for bulk NbSe2, PbSe and SnSe, with the crystallographic c-axes parallel to the stacking direction in the ferecrystals. A quantitative analysis using a two-layer model fit for the electrical resistivity, Hall coefficient and magnetoresistance yields a similar carrier type, density and mobility in the NbSe2 layers as reported for isolated NbSe2 monolayers. These values differ from those of bulk NbSe2. For the first time, a normal-to-superconducting transition has been detected in ferecrystals. The transition temperatures of the ferecrystals are reduced to about a half of those of analogous non-disordered misfit layer compounds. This reduction in transition temperature can be correlated to the turbostratic disorder in ferecrystals. The ratio between the cross-plane Ginzburg-Landau coherence length and the cross-plane distance between the NbSe2 layers for the ferecrystals is lower than for non-disordered misfit layer compounds, making ferecrystals promising candidates for (quasi-)two-dimensional superconductors.
Wahl, Reiner. "Reguläre bakterielle Zellhüllenproteine als biomolekulares Templat." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2003. http://nbn-resolving.de/urn:nbn:de:swb:14-1055925295812-40846.
Full textBakterielle Zellhüllenproteine (S-Layer) eignen sich durch ihre Fähigkeit zur Selbstassemblierung zu zweidimensionalen Kristallen und durch ihre besonderen chemischen und strukturellen Eigenschaften zur Abscheidung regelmäßiger metallischer Partikel auf ihrer Oberfläche. In dieser Arbeit wird das Clusterwachstum auf S-Layern untersucht. Die Anbindung von Metallkomplexen an S-Layer von Bacillus sphaericus und Sporosarcina ureae und deren Reduktion führt zur Abscheidung periodisch angeordneter metallischer Platin- bzw. Palladiumcluster auf dem Biotemplat. Für diese Clusterbildung wird ein heterogener Keimbildungsmechanismus vorgeschlagen, bestehend aus Komplexanbindung und Reduktion. Die Bestimmung der Prozeßkinetik und die Charakterisierung der Anbindung der Komplexe an das Protein erfolgt mittels UV/VIS-Spektroskopie. Den Schwerpunkt dieser Arbeit bilden strukturelle Untersuchungen mit Hilfe der Transmissionselektronenmikroskopie, der Elektronenholographie, der Rasterkraftmikroskopie und der Bildanalyse und Bildverarbeitung. Durch Korrelationsmittelung werden Strukturinformationen gewonnen, die eine Bestimmung der lateral bevorzugten Clusterpositionen ermöglichen. Für die auf S-Layern erzeugten Clusterarrays wird die Belegung der einzelnen Positionen mittels Multivariater Statistischer Analyse genauer quantifiziert. Außerdem werden eine Methode zur Erzeugung hochgeordneter metallischer Partikelarrays unter dem Einfluß des Elektronenstrahles im Transmissionselektronenmikroskop und eine Methode zum schnellen Test Gram-positiver Bakterienstämme auf die Existenz von S-Layern vorgestellt
Brockt, Georg. "Nano-Charakterisierung struktureller und optischer Eigenschaften von Gruppe-III-Nitrid-Heterostrukturen im Raster-Transmissionselektronenmikroskop (RTEM)." [S.l.] : [s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=965262391.
Full textAranha, Galves Lauren. "Fabrication and characterization of graphene nanoribbons epitaxially grown on SiC(0001)." Doctoral thesis, Humboldt-Universität zu Berlin, 2018. http://dx.doi.org/10.18452/19587.
Full textMonolayer graphene nanoribbons (GNRs) were synthesized on SiC(0001) substrates with two different miscut angles at temperatures ranging from 1410 to 1460 °C. The GNR growth in lower step heights is best described by an exponential growth rate, which is correlated with the energy barrier for Si out-diffusion. On the other hand, a non-exponential rate is observed for substrates with higher steps, which is associated with the formation of few-layer graphene on the step edges. Oxygen intercalation of epitaxial GNRs is investigated next by air annealing ribbons grown in different SiC(0001) substrates. Besides the conversion of monolayer into bilayer graphene near the step edges of SiC, the oxygen intercalation also leads to the formation of an oxide layer on the terraces of the substrate, leaving the bilayer GNRs electronically isolated from each other. Electrical characterization of bilayer GNRs reveals that the ribbons are electrically decoupled from the substrate by the oxygen treatment. A robust hole concentration of around 1x10¹³ cm-² and mobilities up to 700 cm²/(Vs) at room temperature are measured for GNRs whose typical width is 100 nm. Well defined mesa structures patterned by electron beam lithography on the surface of SiC substrates is lastly researched. Transport characterization of GNRs grown on the sidewalls of the patterned terraces shows a mobility in the range of 1000 – 2000 cm²/(Vs), which is homogeneous for various structures throughout the sample, indicating the reproducibility of this fabrication method and its potential for implementation in future technologies based on epitaxially grown GNRs.