Thèses sur le sujet « 2D oxides »
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SCALISE, EMILIO. « Vibrational Properties of Defective Oxides and 2D Nanolattices ». Doctoral thesis, KuLeuven, 2013. http://hdl.handle.net/10281/181816.
Texte intégralOdziomek, Mateusz Janusz. « Colloidal Synthesis and Controlled 2D/3D Assemblies of Oxide Nanoparticles ». Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEN092/document.
Texte intégralNanotechnology has become a key domain of technology in XXI century. The great development of the synthetic approaches toward nanoparticles (NPs) with desired composition, size and shape expose the potential of their use as building blocks for larger scale structures. It allows fabrication of functional materials and devices directly from colloids by bottom-up approach, thus involving possibility of material design over several length scales. The process is referred to NPs assembly or self-assembly and leads to materials with varying architectures as for instance 1D (rods), 2D (films) or 3D (superlattices or gels). However most of 3D assemblies are limited to the micrometric scale and are difficult to control. Practically the only route allowing preparation of macroscopic 3D structures from NPs is their gelation and preparation of aerogels. As an alternative, NPs can be embedded in some matrix creating bulk composite material, with homogenously distributed non-aggregated NPs.Therefore, this work is devoted to development of materials with different dimensionalities for various applications from metal oxides NPs (mainly Y3Al5O12:Ce and Li4Ti5O12). The first part describes the syntheses of YAG:Ce and LTO NPs by glycothermal approach. In the case of YAG:Ce, the reactions conditions were appropriately adjusted in order to obtain non-aggregated nanocrystals (NCs) of few nanometers. The colloidal solution containing such NCs with different concentration was used for fabrication of thin films with controllable thickness by spin-coating method. Contrary, the synthesis of LTO led to aggregated NPs with hierarchical structuration which was highly beneficial for Li-ion batteries. The large surface area and porosity ensured efficient exchange of Li ions between electrolyte and anode material. Furthermore, the YAG:Ce NCs were used for preparation of macroscopic monoliths with high porosity and transparency. For that reason, colloidal solution of NCs was gelled by the abrupt change of solvent dielectric constant. The gels were further supercritically dried yielding YAG:Ce NPs-based aerogels with high porosity and transparency. The same approach turned o be appropriate for other systems like GdF3 or hybrid aerogels of YAG:Ce and GdF3.Alternatively, YAG:Ce NPs were incorporated into silica aerogels forming robust macroscopic and highly transparent aerogels exhibiting properties of incorporated NPs. They served for novel type of sensors for low-energy ionizing radiation in liquids and gases. Their high porosity assured well-developed contact between radioactive emitter and the scintillator ensuring good harvesting of radioactive energy
Paerschke, Ekaterina. « Interplay of Strong Correlation, Spin-Orbit Coupling and Electron-Phonon Interactions in Quasi-2D Iridium Oxides ». Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-235245.
Texte intégralAsel, Thaddeus J. « Nanoscale Characterization of Defects in Complex Oxides and Germanane ». The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1523982077791833.
Texte intégralTreske, Uwe. « Valence changes at interfaces and surfaces investigated by X-ray spectroscopy ». Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-162589.
Texte intégralIn der vorliegenden Dissertation werden Valenzänderungen an Grenzflächen und Oberflächen mittels Verfahren der Röntgenspektroskopie untersucht, zu denen die Röntgenphotoelektronen- (XPS), die Röntgenabsorptions- (XAS) und die resonante Photoelektronenspektroskopie (ResPES) gehören. Kapitel 3 behandelt die elektronischen Eigenschaften der Oxide LaAlO3, LaGaO3 und NdGaO3, welche mittels Laserdeposition (PLD) auf TiO2-terminierte SrTiO3 Einkristalle entlang (001)-Richtung gewachsen wurden. Diese polaren/nicht-polaren Oxidgrenzflächen weisen einen Isolator-Metall Phasenübergang als Funktion der Schichtdicke auf, bei dem sich ein zwei dimensionales Elektronengas an der Grenzfläche bildet. Die Eigenschaften dieser Ladungsträger, deren Konzentration und räumliche Ausdehnung, sowie der Verlauf der Energiebänder an der Grenzfläche werden vergleichend untersucht und quantitativ bestimmt. Es wird gezeigt, dass sich die drei untersuchten Grenzflächen, trotz unterschiedlicher Gitterkonstanten und Energiebandlücken, ähnlich verhalten. Das mit der Schichtdicke ansteigende Ti3+ Signal wird im Ti 2p XPS, Ti L-Kante XAS und durch die resonant verstärkten Ti 3d Anregungen nahe EF (ResPES) nachgewiesen. Daraus lässt sich schlussfolgern, dass in allen Fällen eine SrTiO3 Schicht mit einer Dicke von 4nm der eigentlich aktive Bereich ist. Im SrTiO3 tritt eine Bandverbiegung auf, ein elektrisches Feld in der polaren Deckschicht kann jedoch nicht nachgewiesen werden. Grundlegende Aspekte dieser Ergebnisse sind in einem Szenario vereinbar, bei dem die polaren Kräfte durch die Entstehung von Oberflächendefekten, durch die Trennung von photoneninduzierten Elektronen-Lochpaaren und durch eine elektronische Umordnung bei 4 uc Schichtdicke eliminiert werden. Des Weiteren werden Abweichungen von einer abrupten Grenzfläche mittels weich-Röntgenphotoelektronenspektroskopie festgestellt, die die Grenzflächeneigenschaften beeinflussen können. Für oberflächenempfindlichere Messbedingungen zeigt die Sr 3d Anregung, im Gegensatz zu Rumpfniveaus anderer Elemente, eine unerwartete Aufspaltung, was nur durch das Vorhandensein einer zweiten chemischen Strontiumkomponente zu erklären ist. Aus quantitativen Betrachtungen lässt sich schließen, dass einige Strontiumatome während des Wachstums an die Oberfläche diffundieren und möglicherweise Strontiumoxid gebildet wird. Der zweite Schwerpunkt der vorliegenden Arbeit ist die Untersuchung von Schwer-Fermionen Supraleitern CeMIn5 (M = Co, Rh, Ir) mittels temperatur- und winkelabhängiger XPS. Bei dieser Materialklasse dominiert das feine Zusammenspiel zwischen lokalisierten Ce 4f und frei beweglichen Leitungselektronen die elektronischen Eigenschaften. Das Ce 3d Rumpfniveauspektrum besitzt für die drei Materialien eine sehr ähnliche Form, die auf eine schwache f-Hybridisierung schließen lässt. Die Spektren werden mittels einer vereinfachten Version des Anderson-Impurity Modells analysiert, wobei sich eine Ce 4f Besetzung von mehr als 0,9 ergibt. Die Temperaturabhängigkeit zeigt eine kontinuierliche und irreversible Verbreiterung ausschließlich für die Ce 3d Anregung, dieser Umstand kann einer Oxidation der reaktiven Ceratome an der Oberfläche zugeordnet werden
Crowley, Kyle McKinley. « Electrical Characterization, Transport, and Doping Effects in Two-Dimensional Transition Metal Oxides ». Case Western Reserve University School of Graduate Studies / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=case1597327584506971.
Texte intégralRuano, Merchán Catalina. « Synthesis and characterization of 2D complex oxide films in the SrTiO₃/Pt(111)/Al₂O₃(0001) system ». Electronic Thesis or Diss., Université de Lorraine, 2022. http://www.theses.fr/2022LORR0039.
Texte intégralThe formation of 2D dodecagonal quasicrystalline oxides (OQC), as related approximant phases were recently reported in thin films derived from BaTiO₃ or SrTiO₃ perovskites deposited on (111)-oriented Pt single crystal. These 2D structures add novel functionalities to the ultra-thin films of ternary oxides supported on metals when approaching the 2D limit. Here, we use a thin film stacking approach in which the single crystal is replaced by a Pt (111) buffer layer, deposited by MBE on an Al₂O₃(0001) substrate. An ultra-thin film of SrTiO₃ was subsequently deposited by PLD. The film stacking is fully characterized by diffraction (LEED, RHEED, XRD),microscopy (STM, TEM, Nano-SAM) and spectroscopy (XPS, AES) techniques. We report the discovery of three OQC approximants obtained by reducing this system by annealing at high temperature under vacuum conditions. These phases can be described by three different tilings constructed with NGT elements. An atomic model determined by DFT, in agreement with the experimental observations, is proposed for each approximant. This thin-film approach can be useful for exploring the formation of complex 2D oxide phases in other metal-oxide combinations
Paerschke, Ekaterina [Verfasser], Jeroen van den [Akademischer Betreuer] Brink, Jeroen/van den [Gutachter] Brink et Krzysztof [Gutachter] Wohlfeld. « Interplay of Strong Correlation, Spin-Orbit Coupling and Electron-Phonon Interactions in Quasi-2D Iridium Oxides / Ekaterina Paerschke ; Gutachter : Jeroen van den Brink, Krzysztof Wohlfeld ; Betreuer : Jeroen van den Brink ». Dresden : Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://d-nb.info/1160875170/34.
Texte intégralPärschke, Ekaterina [Verfasser], Jeroen van den [Akademischer Betreuer] Brink, Jeroen/van den [Gutachter] Brink et Krzysztof [Gutachter] Wohlfeld. « Interplay of Strong Correlation, Spin-Orbit Coupling and Electron-Phonon Interactions in Quasi-2D Iridium Oxides / Ekaterina Paerschke ; Gutachter : Jeroen van den Brink, Krzysztof Wohlfeld ; Betreuer : Jeroen van den Brink ». Dresden : Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://d-nb.info/1160875170/34.
Texte intégralMayer-Uhma, Tobias. « Von molekularen Precursoren zu Oxidphasen im System V2O5 / Nb2O5. Darstellung, Eigenschaften, katalytische Aktivität ». Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2004. http://nbn-resolving.de/urn:nbn:de:swb:14-1107505327269-01068.
Texte intégralIn der Arbeit werden durch die Synthese gemischter Alkoxide der Gesamtzusammensetzung [V(O)Nbx(OR)(3+5x)] (R = n-C3H7 und C2H5, x = 1, 4,5 und 9) sowie gefriergetrockneter Pulver Ausgangssubstanzen für gemischte, komplexe Vanadium- und Nioboxide erhalten. Untersuchungen mittels UV/VIS-, Resonanz-Raman- und IR-Spektroskopie sowie temperaturabhängiger 51V- und zweidimensionaler 1H-/13C NMR-Spektroskopie zeigen, dass es sich bei der Alkoxid-Vorstufe um ein Gemisch aus monomeren und dimeren Einheiten handelt, die in schnellem Gleichgewicht miteinander stehen. So liegt [V(O)Nb(OPr)8] als Donorkomplex vor, der im Gleichgewicht mit VO(OPr)3 und Nb(OPr)5 steht. Nb(OPr)5 steht wiederum im Gleichgewicht mit [Nb(OPr)5]2. Die Bildung und der Zerfall des Donorkomplexes erfolgen bei Raumtemperatur so schnell, dass er nur durch UV/VIS- und Resonanz-Raman-Spektroskopie sichtbar wird; bei der Kernresonanzspektroskopie muss der Austausch durch tiefe Temperaturen verlangsamt werden.Mittels kontrollierter Hydrolyse einer Mischung aus VO(OPr)3 und [Nb(OEt)5]2 in Propanol mit Oxalsäure als Chelatbildner und der Verlangsamung der Kondensation über die Erniedrigung der Temperatur wird ein homogenes, transparentes Gel aus V2O5 und Nb2O5 hergestellt. Daneben wird durch eine Lösung aus Ammoniumvanadat und Ammoniumoxyoxalatoniobat ein für die Gefriertrocknung geeigneter Precursor zur Synthese der Oxidphasen gefunden. Die Zersetzung des Gels und der gefriergetrockneten Pulver werden mittels DTA, TG und Massenspektrometrie untersucht und die Phasenausbildung mit der Reaktion von konventionellen Festkörpergemengen verglichen.Die dabei entstehenden metastabilen und thermodynamisch stabilen Phasen VNbxO(2,5+2,5x) (x = 1, 4,5 und 9) sind durch das Sol-Gel-Verfahren sowie durch die Gefriertrocknung bei deutlich niedrigeren Temperaturen und mit geringerem Fremdphasenanteil als bei der konventionellen Synthese erhältlich. VNbO5 existiert bis 650 °C, V4Nb18O55 bis 750 °C, darüber wandelt sich jede Zusammensetzung in VNb9O25 bzw. in verschiedene Nb2O5-Modifikationen und V2O5 um. Die Sol-Gel-Methode liefert im Vergleich zur Gefriertrocknung bei 900-1100 °C den Vorteil der schnelleren Phasenausbildung durch die größere Homogenität der Vorstufe. So erhält man Zwischenstufen, die sonst nur mit Beimengungen zu synthetisieren sind. In diesem Zusammenhang kann erstmalig eine zu M-Nb2O5 homöotype Verbindung der Zusammensetzung VNb9O25 erhalten werden. Ein weiterer Vorteil der Sol-Gel-Synthese ist der Erhalt größerer Oberflächen nach der Zersetzung. Nachteilig erscheinen jedoch bei einer Synthese bei tiefen Temperaturen (500-800 °C) die Alkoholatreste. So entstehen wesentlich eher die thermodynamisch begünstigten Phasen, z. B. VNb9O25 vor V4Nb18O55 und V4Nb18O55 vor VNbO5. Weiterhin macht sich die komplizierte Präparation der Gele bemerkbar; daher stellt im Allgemeinen die Gefriertrockung die Methode der Wahl dar.Die Ausbildung der komplexen Oxide erfolgt stark geprägt durch die Thermodynamik an den Phasengrenzen. Daher erfolgt eine bevorzugte Ausbildung strukturähnlicher Mischphasen. Diese erstmalig in diesem Ausmaß festgestellte Tatsache wird in der Arbeit der Strukturdirigierende Effekt genannt. Eine Erklärung dieses Effektes erfolgt anhand des Verbrauchs der Freien Enthalpie an den Phasengrenzen.Aufgrund eines Synergismus der Eigenschaften von V2O5 und Nb2O5 bei der oxidativen Dehydrierung von Propan zu Propen (relativ hohe katalytische Aktivität von V2O5 und hohe Selektivität von Nb2O5) wird eine überproportional hohe katalytische Aktivität bei den Mischoxiden erhalten. Die durch die unkonventionellen Methoden erhaltenen großen Oberflächen verbessern die Aktivität weiter. Es können Zusammenhänge festgestellt werden zwischen der Sauerstoffabgabetendenz, der Redoxkraft, der Bandlücke der Mischoxide und der katalytischen Aktivität. Die Einzigartigkeit des Nb2O5-Wirtsgitters bewirkt bei der Verdünnung von V2O5 darin eine hohe katalytische Leistungssteigerung
Thébaud, Simon. « Electron and phonon transport in disordered thermoelectric materials : dimensional confinement, resonant scattering and localization ». Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1168/document.
Texte intégralOver the past decades, the increasingly pressing need for clean energy sources and the realization that a huge proportion of the world energy consumption is wasted in heat have prompted great interest in developing efficient thermoelectric generation modules. These devices could harvest waste heat from industrial processes or other sources, turning a temperature gradient into a voltage through the Seebeck effect. Efficient thermoelectric materials should exhibit a low thermal conductivity, a high electrical conductivity and a high Seebeck coefficient. Simultaneously optimizing these parameters is a great challenge of condensed matter physics and materials science. With a view to enhance the thermoelectric properties of several promising materials, we explore several strategies in which defects (atomic substitutions, vacancies…), disorder and dimensional confinement play a crucial role. We perform density functional theory calculations and projections on Wannier orbitals to construct realistic Hamiltonians and dynamical matrices describing their electronic and vibrational structure in real space. These parameters are then used to compute the thermoelectric transport properties using the Kubo formalism, the Boltzmann transport equation, the Landauer formalism, and the Chebyshev polynomial Green's function method that allows for an exact treatment of disorder. We investigate the electronic transport properties and thermoelectric performances of two promising materials for high-temperature power generation, strontium titanate and rutile titanium dioxide. Comparison of our predictions with a wealth of experimental data yields a very good agreement. We show that the increase of the Seebeck coefficient observed in strontium titanate superlayers, until now attributed to quantum confinement effects, is in fact well explained assuming delocalized electrons. The general effects of resonant states on electronic transport are explored in a model study, showing a sixfold increase of the thermoelectric performances. The particular case of strontium titanate is then examined, and localization effects are shown to destroy the performances if Vanadium atoms are introduced as resonant impurities. The influence of defects in two-dimensional materials is investigated. Contrary to adatoms, substitutions in transition metal dichalcogenides are shown to localize the charge carriers. We study the effect of vacancies on phonon transport in graphene, and determine the phonon-vacancy scattering rate. Comparison with thermal conductivity data for irradiated and finite-size graphene samples yields a very good agreement between theory and experiments
Lhuillier, Jérémy. « Accordabilité des composants photoniques à base de structures hybrides graphène/diélectrique adressables par la surface ». Electronic Thesis or Diss., Lyon, 2022. https://bibli.ec-lyon.fr/exl-doc/TH_2022LYSEC008.pdf.
Texte intégralThe emergence of a wide variety of photonic structures over the past decades has enabled the realization of on-chip devices performing increasingly complex free-space optical functions. Among them, dielectric membrane structures have made it possible to implement a wide range of planar optical devices, ranging from resonant spectral filtering to beam shaping, with negligible losses. While these structures provide almost a full control of the radiated electromagnetic field, this control is usually static and determined by manufacturing. An increasing number of applications - such as free-space telecommunications, sensors for autonomous systems or imaging - require agile photonic devices, thus motivating the search for means of active control of the optical response to be implemented within the dielectric structures. To this purpose, various properties of graphene are proving promising. In particular, the capability to modulate its absorption opens up numerous prospects for the electrical and optical control of photonic structures that integrate graphene. This has led to the demonstration of various electro-optic and all-optical modulators, by leveraging the recently developed 2D material transfer processes, which have made it possible to obtain high-quality hybrid graphene/dielectric structures. In this context, the work presented in this thesis seeks to exploit graphene’s tunable absorption to achieve dynamic control of surface-addressable device’s optical response, in the special case of dielectric photonic structures operating in the near infrared. A generic coupled mode theory model is first developed and adapted to hybrid dielectric/ graphene structures in order to identify the key parameters for maximising the control allowed by graphene absorption. In the single resonance case, the system’s response is mainly determined by the critical coupling condition classically defined for the study of graphene’s absorption. In the two-resonance case however, a new control parameter – associated with the absorption difference between the resonances – provides an additional tunability factor. Different strategies for maximising this parameter are therefore proposed and the technological processes underlying their implementation are studied experimentally in order to assess - by means of Raman spectroscopy and photoelectron spectroscopy - their effect on the structural and chemical quality of graphene. The spatial modulation of graphene’s absorption – here proposed to differentiate the absorption induced on different optical modes – is then studied experimentally using structures exploiting the charge transfer effect at the interface between graphene and an oxide with high workfunction, namely tungsten oxide. The devices developed here allow to obtain a graphene’s chemical potential modulation of 0.1eV - characterized by nano-XPS (ANTARES beamline of the SOLEIL synchrotron) and Raman spectroscopy - which can lead to an absorption modulation higher than 70% for certain wavelengths. Ultimately, an active hybrid device architecture enabling dynamic control of the laser emission is proposed. This architecture is based on a vertical symmetry breaking membrane and allows us, in principle, to switch between two emission angles by modulating graphene’s absorption. The interest of these structures in achieving continuous tunability of the emission angle is also presented
Zhang, Yubai. « Electrochemical synthesis of 2D materials and their applications in energy storage ». Thesis, Griffith University, 2021. http://hdl.handle.net/10072/410071.
Texte intégralThesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment and Science
Science, Environment, Engineering and Technology
Full Text
Wu, Ziyang. « Rational design of two-dimensional architectures for efficient electrocatalysis ». Thesis, Queensland University of Technology, 2022. https://eprints.qut.edu.au/235888/1/ziyang%2Bwu%2Bthesis%284%29.pdf.
Texte intégralKang, Seungyeon. « Femtosecond laser direct writing of 3D metallic structures and 2D graphite ». Thesis, Harvard University, 2014. http://dissertations.umi.com/gsas.harvard:11495.
Texte intégralEngineering and Applied Sciences
Tararan, Anna. « Spectroscopy in fragile 2D materials : from Graphene Oxide to single molecules at hexagonal Boron Nitride ». Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS441/document.
Texte intégralElectron energy loss spectroscopy (EELS) and cathodoluminescence(CL) in a scanning transmission electron microscope (STEM) are extremely powerful techniques for the study of individual nanostructures. Nevertheless, fast electrons damage extremely sensitive thin specimens, imposing strong limitations on the spatial resolution and the intensity of spectroscopic measurements. During this thesis we have overcome this restriction by developing material-specific acquisition protocols for the study of some archetypical fragile nanosystems. In the first part of this thesis we have characterized graphene oxide (GO) and reduced graphene oxide (RGO) thin flakes by EELS spectroscopy in the STEM. Thanks to the particular setup of our microscope and by experimentally defining the optimal illumination conditions, we have derived oxygen quantification maps of (R)GO at an unprecedented spatial resolution. On the basis also of EELS fine structures analysis, we have revised the existing proposed atomic models for these materials. Another class of exceedingly sensitive nanometric systems is represented by individual molecules, which are strongly affected by both illumination and chemical/physical environment. We have performed the first CL-STEM investigation on the luminescence of isolated molecules, thanks to a watchful choice of the substrate. Hexagonal boron nitride (h-BN) is a flat, chemically inert 2D material, that actively takes part in the CL process by absorbing the incident energy. Excitation transfer from h-BN to molecules and the use of an innovative random scan acquisition routine in the STEM have allowed to considerably lower illumination effects and improve CL intensity. Afterwards, the attractive optical properties of h-BN have led to the study of its cubic phase (c-BN), which has been up to now hindered by the poor quality of the crystals. By EELS in the STEM we have analysed c-BN crystals of the highest available purity, identifying a wider optical band-gap with respect to previous experimental studies and in better agreement with recent calculations. In commercial crystals, several defect-related emissions have been identified and analysed in terms of characteristic energy, spatial distribution and lifetime using CL and Hanbury-Brown and Twiss intensity interferometry
Hu, Xiao. « Ultra-thin oxide films ». Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:d7373376-84f1-459e-bffb-f16ce43f02b7.
Texte intégralGonzalez, Ortiz Dánae. « DEVELOPMENT OF POROUS MEMBRANES FROM EMULSIONS STABILIZED BY 2D NANOPARTICLES (h-BNNS) ». Thesis, Montpellier, Ecole nationale supérieure de chimie, 2018. http://www.theses.fr/2018ENCM0006/document.
Texte intégralEmulsions stabilized through the adsorption of colloidal particles at the liquid-liquid interface have been of interest in a wide variety of applications, ranging from pharmaceutical or food products to templates for the preparation of new materials. In this thesis, oil-in-water (O/W) and water-in-oil (W/O) emulsions are efficiently stabilized using colloidal inorganic particles (graphene oxide (GO) and hexagonal boron nitride nanosheets (h-BNNS)). The adsorption of particles to the oil-water interface is induced by adjusting the particle wetting behavior in the liquid media. Two types of emulsions, O/W and W/O are formed by using two-dimensional materials possessing different hydrophilic behaviors. The conditions required to reach the most stable emulsion using two different types of particles at different formulations are investigated. The final microstructures of the mixtures are tailored by adjusting the initial composition of emulsion. The use of high concentration of particles leads to enhanced stability of particles-stabilized emulsions. h-BNNS based emulsions were reported in this work for the first time and their behavior was deeply investigated. Furthermore, a novel green approach to obtain polyvinyl alcohol (PVA)-based porous membranes was reported. In this case, the addition of PVA to the emulsion increases its long term stability and allows its shaping using conventional technologies such as casting. The polymer composites obtained from emulsions stabilized with inorganic particles exhibit microporosity, showing typical pore dimensions of 0.19 ± 0.03 µm or 1.1 ± 0.3 µm depending on the curing time. These obtained porous membranes display good performance in water permeability and particle rejection. Membranes displaying a pore size about 1.1 µm showed water permeability about 2000 L/h m2 bar, and a rejection rate of 86 % with particles of the same size than the pores
Dedigamuwa, Gayan S. « Formation of nanocoatings by laser-assisted spray pyrolysis and laser ablation on 2d gold nanotemplates ». [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001205.
Texte intégralMuchharla, Baleeswaraiah. « Low Temperature Electrical Transport in 2D Layers of Graphene, Graphitic Carbon Nitride, Graphene Oxide and Boron-Nitrogen-Carbon ». OpenSIUC, 2015. https://opensiuc.lib.siu.edu/dissertations/1132.
Texte intégralPakulski, Dawid. « Graphene based materials and their potential applications ». Thesis, Strasbourg, 2019. http://www.theses.fr/2019STRAF060.
Texte intégralScientific purpose of this doctoral dissertation is synthesis of functionalized two-dimensional materials (graphene and graphene oxide) and their comprehensive physicochemical characterization, with particular emphasis on adsorption and energy storage properties. We could demonstrate that covalent modification of graphene oxide (GO) with an organic polymer (BPEI) very favorably affects the efficiency of the adsorption process. The maximum adsorption capacity (qmax) values for heavy metal ions significantly favour this material in comparison to the majority of known carbon adsorbents. Moreover, functionalization of GO with mesoporous aminosilica (SiO2NH2) leads to obtaining an efficient and rapid adsorbent of organic cationic dyes (MB, RhB, MV). ln addition we proved that the functionalization of graphene (EEG) using the POM-surfactant su bu nits proved that this type of organic-inorganic hybrids material is very stable and have interesting electrical properties with potential application in the production of supercapacitors
Ciornii, Dmitri. « Performance-oriented strategies for integration and wiring of the photosystem I inside 2D and 3D architectures and coupling photocatalysis with enzymatic catalysis ». Doctoral thesis, Humboldt-Universität zu Berlin, 2020. http://dx.doi.org/10.18452/21813.
Texte intégralIn this thesis, different strategies for coupling of the natural complex photosystem I from the cyanobacterium Thermosynechococcus elongatus with different electrode surfaces, and the interaction of PSI with nanomaterials and enzymes has been investigated. First, it was shown that immobilization of PSI on modified multi-walled carbon nanotubes (MWNT) leads to a functional photobiohybrid electrode. Here, PSI has been electrically wired to the electrode via a redox-active protein, cytochrome c (cyt c). The system (PSI-cyt c) has been scaled up to the three-dimensional surface of a metal-oxide, indium tin oxide (ITO). Here, additionally the high transparency property of this material has been exploited. The new preparation procedure of such transparent electrodes has been optimized in order to achieve high pohotocurrents. Furthermore, a new method of electric wiring of the PSI with the electrode has been established. Here, fullerenes have been employed. The high molecular efficiency of such a system proves that fullerenes are more effective wiring agents between the PSI and the electrode as compared to the cyt c. Additionally, in this thesis the photocatalytic property of the PSI has been combined with the biocatalytic property of the enzyme human sulphite oxidase, hSOx. Here, the enzyme has been employed as an alternative electron supplier for PSI. The third protein, cyt c, acted as an electric wiring agent and ensured electric communication between both catalytic proteins of the system and the electrode. The versatility of the PSI as well as its communication with anorganic nanomaterials and biological molecules, e.g. such as enzymes, shows a great potential for use of PSI-based biohybrids in the future biotechnological applications.
Akrobetu, Richard K. « The Interplay of Surface Adsorbates and Cationic Intermixing in the 2D Electron Gas Properties of LAO-STO Heterointerfaces ». Case Western Reserve University School of Graduate Studies / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=case1491575404930072.
Texte intégralHaidar, Fatima. « Nanostructures 2D et supports d’oxydes métalliques pour des cathodes de piles à combustible à faible teneur en platine ». Thesis, Montpellier, 2018. http://www.theses.fr/2018MONTS121.
Texte intégralProton exchange membrane fuel cells are clean and efficient energy converters. Their accessible power ranges allow their use in the field of transport or stationary applications. Two main challenges concern the cathode deployment:i) The reduction of the amount of low abundant platinum group metal in the catalyst.ii) The enhancement of stability of the catalyst support at high voltage.In this work we present two strategies to address these challenges and improve performance and durability of the cathodes: developing novel ultra-low loaded platinum electrocatalysts and corrosion resistant support materials.To reduce noble metal amount in the catalyst, we developed platinum thin films, which allow maximal electrocatalytic exploitation thus minimal loading. For that, we have used electrochemical methods based on under-potential deposition and galvanic displacement. The thin structures deposited on model substrates were characterized by electrochemical, elemental analysis and microscopy techniques.To prepare corrosion resistant supports, our strategy was the replacement of conventional carbon black with a doped conducting tin oxide. SnO2-based materials have been demonstrated as electrochemical stable supports also promoting platinum activity for the oxygen reduction reaction. In this work, tantalum-doped tin oxide was prepared by electrospinning followed by calcination, leading to a fiber-in-tube morphology. This support was catalyzed with platinum nanoparticles prepared by a microwave-assisted polyol method, and characterized for their physico-chemical and electrocatalytic properties. In particular, stability to voltage cycling was evaluated by ex situ electrochemical analysis.The possibility to associate the extended surface electrocatalyst with the corrosion resistant supports to obtain active and durable cathodes is in progress
Huang, Yinjuan, Rui Yuan, Fugui Xu, Yiyong Mai, Xinliang Feng et Deyue Yan. « Ultra-large sheet formation by 1D to 2D hierarchical self-assembly of a “rod–coil” graft copolymer with a polyphenylene backbone ». Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-225638.
Texte intégralHuang, Yinjuan, Rui Yuan, Fugui Xu, Yiyong Mai, Xinliang Feng et Deyue Yan. « Ultra-large sheet formation by 1D to 2D hierarchical self-assembly of a “rod–coil” graft copolymer with a polyphenylene backbone ». Royal Society of Chemistry, 2016. https://tud.qucosa.de/id/qucosa%3A30347.
Texte intégralGut, Stephan [Verfasser], Christoph [Akademischer Betreuer] Alexiou, Christoph [Gutachter] Alexiou et Diana [Gutachter] Dudziak. « Cellular effects of paclitaxel-loaded iron oxide nanoparticles on breast cancer using different 2D and 3D cell culture models / Stephan Gut ; Gutachter : Christoph Alexiou, Diana Dudziak ; Betreuer : Christoph Alexiou ». Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2021. http://d-nb.info/1241827273/34.
Texte intégralLee, Veronica. « A Combined Theoretical and Experimental Study on Deposition of Solid State Materials ». Thesis, University of North Texas, 2020. https://digital.library.unt.edu/ark:/67531/metadc1707299/.
Texte intégralChicot, Gauthier. « Effet de champs dans le diamant dopé au bore ». Phd thesis, Université de Grenoble, 2013. http://tel.archives-ouvertes.fr/tel-01062250.
Texte intégralPezzotti, Simone. « DFT-MD simulations and theoretical SFG spectroscopy to characterize H-Bonded networks at aqueous interfaces : from hydrophobic to hydrophilic environments Structural definition of the BIL and DL : a new universal methodology to rationalize non-linear χ(2)(ω) SFG signals at charged interfaces, including χ(3)(ω) contributions What the Diffuse Layer (DL) Reveals in Non-Linear SFG Spectroscopy 2D H-Bond Network as the Topmost Skin to the Air-Water Interface Combining ab-initio and classical molecular dynamics simulations to unravel the structure of the 2D-HB-network at the air-water interface 2D-HB-Network at the air-water interface : A structural and dynamical characterization by means of ab initio and classical molecular dynamics simulations Spectroscopic BIL-SFG Invariance Hides the Chaotropic Effect of Protons at the Air-Water Interface Molecular hydrophobicity at a macroscopically hydrophilic surface Graph theory for automatic structural recognition in molecular dynamics simulations DFT-MD of the (110)-Co3O4 cobalt oxide semiconductor in contact with liquid water, preliminary chemical and physical insights into the electrochemical environment ». Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLE008.
Texte intégralImproving our knowledge on water H-Bonded networks formed in the special environment offered by an interface is pivotal for our understanding of many natural phenomena and technological applications. To reveal the interfacial water arrangement, techniques able to provide detailed microscopic information selectively for the interfacial layer are required. In the present thesis work, we have hence investigated aqueous interfaces at the molecular level, by coupling theoretical modeling from DFT-MD simulations with SFG & THz-IR spectroscopies. By developing new investigation protocols/tools, coupling DFT-MD simulations and SFG spectroscopy, in particular for the more complex rationalization of charged interfaces, we have provided a global comprehension of the effect of various interfacial conditions (hydrophilicity, pH, ionic strength) on the HB-Network formed in the interfacial layer (BIL), on its spectroscopic signatures and on its impact on physico-chemical properties. We have shown for the first time that, in sufficiently hydrophobic conditions, BIL interfacial water creates special 2-Dimensional HB-Networks, experimentally revealed by one specific THz-IR marker band. Such 2D-network dictates HBs and orientational dynamics of interfacial water, surface potential, surface acidity, water surface tension and thermodynamics of hydration of hydrophobic solutes. Such "horizontal ordering” of water at hydrophobic interfaces is found opposite to the “vertical ordering” of water at hydrophilic interfaces, while coexistence of the two orders leads to disordered interfacial water in intermediate hydrophilic/hydrophobic conditions. Both DFT-MD and SFG further revealed how ions & pH conditions alter these BIL-water orders
Das, Ranjan. « Optoelectronic and Magnetic Properties of 2D Layered Organic-Inorganic Hybrids and Selected Transition Metal Oxides ». Thesis, 2022. https://etd.iisc.ac.in/handle/2005/6164.
Texte intégralPärschke, Ekaterina. « Interplay of Strong Correlation, Spin-Orbit Coupling and Electron-Phonon Interactions in Quasi-2D Iridium Oxides ». Doctoral thesis, 2017. https://tud.qucosa.de/id/qucosa%3A30957.
Texte intégralTreske, Uwe. « Valence changes at interfaces and surfaces investigated by X-ray spectroscopy ». Doctoral thesis, 2014. https://tud.qucosa.de/id/qucosa%3A28574.
Texte intégralIn der vorliegenden Dissertation werden Valenzänderungen an Grenzflächen und Oberflächen mittels Verfahren der Röntgenspektroskopie untersucht, zu denen die Röntgenphotoelektronen- (XPS), die Röntgenabsorptions- (XAS) und die resonante Photoelektronenspektroskopie (ResPES) gehören. Kapitel 3 behandelt die elektronischen Eigenschaften der Oxide LaAlO3, LaGaO3 und NdGaO3, welche mittels Laserdeposition (PLD) auf TiO2-terminierte SrTiO3 Einkristalle entlang (001)-Richtung gewachsen wurden. Diese polaren/nicht-polaren Oxidgrenzflächen weisen einen Isolator-Metall Phasenübergang als Funktion der Schichtdicke auf, bei dem sich ein zwei dimensionales Elektronengas an der Grenzfläche bildet. Die Eigenschaften dieser Ladungsträger, deren Konzentration und räumliche Ausdehnung, sowie der Verlauf der Energiebänder an der Grenzfläche werden vergleichend untersucht und quantitativ bestimmt. Es wird gezeigt, dass sich die drei untersuchten Grenzflächen, trotz unterschiedlicher Gitterkonstanten und Energiebandlücken, ähnlich verhalten. Das mit der Schichtdicke ansteigende Ti3+ Signal wird im Ti 2p XPS, Ti L-Kante XAS und durch die resonant verstärkten Ti 3d Anregungen nahe EF (ResPES) nachgewiesen. Daraus lässt sich schlussfolgern, dass in allen Fällen eine SrTiO3 Schicht mit einer Dicke von 4nm der eigentlich aktive Bereich ist. Im SrTiO3 tritt eine Bandverbiegung auf, ein elektrisches Feld in der polaren Deckschicht kann jedoch nicht nachgewiesen werden. Grundlegende Aspekte dieser Ergebnisse sind in einem Szenario vereinbar, bei dem die polaren Kräfte durch die Entstehung von Oberflächendefekten, durch die Trennung von photoneninduzierten Elektronen-Lochpaaren und durch eine elektronische Umordnung bei 4 uc Schichtdicke eliminiert werden. Des Weiteren werden Abweichungen von einer abrupten Grenzfläche mittels weich-Röntgenphotoelektronenspektroskopie festgestellt, die die Grenzflächeneigenschaften beeinflussen können. Für oberflächenempfindlichere Messbedingungen zeigt die Sr 3d Anregung, im Gegensatz zu Rumpfniveaus anderer Elemente, eine unerwartete Aufspaltung, was nur durch das Vorhandensein einer zweiten chemischen Strontiumkomponente zu erklären ist. Aus quantitativen Betrachtungen lässt sich schließen, dass einige Strontiumatome während des Wachstums an die Oberfläche diffundieren und möglicherweise Strontiumoxid gebildet wird. Der zweite Schwerpunkt der vorliegenden Arbeit ist die Untersuchung von Schwer-Fermionen Supraleitern CeMIn5 (M = Co, Rh, Ir) mittels temperatur- und winkelabhängiger XPS. Bei dieser Materialklasse dominiert das feine Zusammenspiel zwischen lokalisierten Ce 4f und frei beweglichen Leitungselektronen die elektronischen Eigenschaften. Das Ce 3d Rumpfniveauspektrum besitzt für die drei Materialien eine sehr ähnliche Form, die auf eine schwache f-Hybridisierung schließen lässt. Die Spektren werden mittels einer vereinfachten Version des Anderson-Impurity Modells analysiert, wobei sich eine Ce 4f Besetzung von mehr als 0,9 ergibt. Die Temperaturabhängigkeit zeigt eine kontinuierliche und irreversible Verbreiterung ausschließlich für die Ce 3d Anregung, dieser Umstand kann einer Oxidation der reaktiven Ceratome an der Oberfläche zugeordnet werden.
Sahoo, Anindita. « Electrical Transport in the Hybrid Structures of 2D Van Der Waals Materials and Perovskite Oxide ». Thesis, 2016. http://etd.iisc.ac.in/handle/2005/2948.
Texte intégralSahoo, Anindita. « Electrical Transport in the Hybrid Structures of 2D Van Der Waals Materials and Perovskite Oxide ». Thesis, 2016. http://etd.iisc.ernet.in/handle/2005/2948.
Texte intégralPAN, JIAN-ZONG, et 潘建宗. « Preparation of 2D Surfactant with Graphene Oxide (GO) ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/33254787113617713250.
Texte intégralChen, Ruei-Shiang, et 陳瑞祥. « 2D/3D CFD Simulation of Metal Oxide Chemical Vapor Deposition (MOCVD) of GaN ». Thesis, 2011. http://ndltd.ncl.edu.tw/handle/18622910568436707550.
Texte intégral國立交通大學
機械工程學系
99
Metal organic chemical vapor deposition (MOCVD) process of GaN in the vertical reactor is studied by various computational fluid dynamics (CFD) simulations under 2D condition. First, with different pressure, figuring out that flow distribution at 100 Torr is stable. Second, we use CFD to analyze temperature distribution inside gap between wafer carrier and substrate, then adding metal film below substrate to process with different temperature. Third, discussing flow distribution stability on substrate with different rotation speed (100rpm-800rpm). Meanwhile, comparing flow influence for temperature at different height from inlet to substrate (16mm–31mm). Trough simulation, if Gr/Re2 number is below 0.5 under 100 Torr, 800 rpm, 1323K and 30,000 sccm condition, the flow distribution is stable. Finally, temperature difference for different height is 0.5K. After 2D simulation, I use 3D CFD simulations implement gas phase chemical reactions and surface chemical reactions for GaN growth from trimethylgallium, nitrogen and ammonia. By fixing condition of total flow rate 30,000 sccm, high speed rotation causes high nonuniformity and high growth rate. Growth Rates for 1,600 rpm rotation plane is twice than 100 rpm. With nonuniformity viewpoint, between 400 rpm and 1,500 rpm plane decreases below 5%. However, low rotation speed as 100 rpm will cause 16% high nonuniformity due to buoyancy influence. On the other hand, through study of flow rate control (7,500sccm–90,000sccm), it will cause different flow distribution and nonuniformity. Especially for ratio of buoyancy influence to plane inertia of momentum and inlet inertia of momentum (Gr/RewRe) discussion, high Gr/RewRe (0.64) will form Rotation–induced flow or vorticity on substrate. As a result, vorticity will caused 6%。In other word, low (Gr/RewRe) between 0.032 to 0.008 will keep stability flow distribution and control below 5%.
Wei, Joy, et 魏巧依. « Crystal orientation of conjugated polymer in the 2D confined space templated by anodic aluminum oxide nanochannels ». Thesis, 2016. http://ndltd.ncl.edu.tw/handle/51020599910853326882.
Texte intégral國立清華大學
化學工程學系
104
The effect of spatial confinement on the structure and phase transition behavior of polymer has been a subject of extensive interest. This study is centered on resolving the preferred orientation of poly(3-hexylthiophene) (P3HT) crystallites formed within the 2D nanoconfined space of Anodic Aluminum Oxide Template (AAO) nanochannels. P3HT is a crystalline semiconduting polymer which has attracted significant attention due to its potential in the application as the active material for bulk heterojunction solar cell and organic field-effect transistors (OFETS). The opto-electronic properties of P3HT are expected to strongly depend on its degree of crystallinity and the gobal arrangement of the crystallites; therefore, controlling these two morphological paraemeters is important for tailoring the photophysical properties of the material. In this work, we incorporated P3HT into AAO nanochannels with the diameter of 20 and 100 nm and examined the crystal orientation within the channels as a function of the post treatment condition Tc by means of 2D wide angle X-ray diffraction patterns collected at BL01C2 and BL17A1 at the National Synchrotron Radiation Research Center (NSRRC). The P3HT crystallites predominantly adopted the edge-on orientation with the crystalline backbone aligning perpendicularly to the long axis of the cylindrical pores since this type of orientation was kinetically favored for the long range crystal growth along the channel axis. However, using AAO nanochannels with smaller diameter and an annealing or recrystallization treatment at 160˚C induced the formation of a small fraction of the face-on orientation. It was also found that the as-cast P3HT in the confined space with smaller pore size exhibited higher degree of crystallinity and better orientation. The samples prepared from the xylene solution generally possessed better orientation and higher crystallinity than those prepared from the THF solution. However, we found that melt recrystallization removed the nucleus in the samples, which hindered the crystal growth, resulting in a decrease in the degree of crystallinity.
Sousa, Ana Rita Lima de. « Development of graphene oxide based nanomaterials for cancer therapy ». Master's thesis, 2018. http://hdl.handle.net/10400.6/9771.
Texte intégralO cancro da mama é uma das principais causas de morte em todo o mundo, afetando principalmente as mulheres. Os tratamentos mais comuns para esta doença incluem a radioterapia e a quimioterapia. No entanto, estas abordagens terapêuticas apresentam uma baixa eficácia e podem, também, induzir efeitos secundários adversos nos pacientes. Desta forma, existe uma enorme necessidade em desenvolver novos tratamentos mais eficazes para o cancro da mama. Neste contexto, diferentes investigadores estão a desenvolver novas abordagens terapêuticas. Em particular, a terapia fototérmica mediada por nanomateriais tem recebido um interesse crescente por parte dos investigadores e profissionais de saúde. Esta abordagem tira partido das propriedades físico-químicas e óticas de alguns tipos de nanomateriais. Estas nanoestruturas responsivas à luz conseguem acumular-se preferencialmente na zona tumoral e posteriormente induzir, após irradiação com luz com um comprimento de onda na região do infravermelho próximo (NIR), um aumento de temperatura que pode danificar as células cancerígenas. Nesta dissertação, materiais à base de óxido de grafeno reduzido (rGO) foram produzidos através de um método de redução ecológico e funcionalizados com um novo polímero anfifílico à base de ácido hialurónico (HA) para aplicação na terapia fototérmica do cancro da mama. O HA foi escolhido devido ao seu carácter hidrofílico e por possuir capacidade de direcionamento para os recetores CD44, que são sobreexpressos na membrana citoplasmática das células do cancro da mama. Os resultados obtidos revelaram que o tratamento do óxido de grafeno com ácido L-ascórbico (3 mM), durante 60 minutos, a 80 ºC, constituem as condições ideais de redução tendo em conta a absorção no NIR apresentada pelo rGO e a distribuição de tamanhos dos materiais obtidos. Posteriormente, a funcionalização do rGO com o polímero anfifílico à base de HA foi efetuada através de interações não-covalentes. A funcionalização melhorou a estabilidade, citocompatibilidade e internalização dos nanomateriais pelas células do cancro da mama que sobreexpressam o recetor CD44, o que confirma a capacidade de direcionamento desta nanoformulação. Adicionalmente, a terapia fototérmica mediada pelo rGO funcionalizado induziu a morte das células cancerígenas, confirmando assim o potencial desta nanoformulação para aplicação na terapia direcionada do cancro da mama.
Yu, Shang-Yu, et 游尚祐. « 2D & ; 3D structuration of solution-based metal oxide precursor via photolithography and its optical/electrical application ». Thesis, 2019. http://ndltd.ncl.edu.tw/handle/u5f674.
Texte intégralBrahma, Madhuchhanda. « Multiscale Modeling of Quantum Transport in 2D Material Based MoS Transistors ». Thesis, 2019. https://etd.iisc.ac.in/handle/2005/5133.
Texte intégralGaddam, Venkateswarlu. « Synthesis and Characterization of 1D & ; 2D Nanostructures : Performance Study for Nanogenerators and Sensors ». Thesis, 2015. http://etd.iisc.ac.in/handle/2005/3886.
Texte intégralGaddam, Venkateswarlu. « Synthesis and Characterization of 1D & ; 2D Nanostructures : Performance Study for Nanogenerators and Sensors ». Thesis, 2015. http://etd.iisc.ernet.in/2005/3885.
Texte intégralGaddam, Venkateswarlu. « Synthesis and Characterization of 1D & ; 2D Nanostructures : Performance Study for Nanogenerators and Sensors ». Thesis, 2015. http://etd.iisc.ac.in/handle/2005/3885.
Texte intégralPan, Jia-Chyi, et 潘嘉琪. « Design and Fabrication of an Inkjet Printed Flexible Tungsten Oxide-Based pH Sensor Array for 2D pH Monitoring of Chronic Wound ». Thesis, 2016. http://ndltd.ncl.edu.tw/handle/52066641576789051963.
Texte intégral國立交通大學
生醫工程研究所
104
In this work, nanoparticle silver ink is printed on kapton, patterned by SU-8, as wire and reference electrode after chlorination. Pre-treated by Tollen’s reagent can not only reduce electrical resistivity of the printed Ag interconnects but also strengthen printed microstructures for sensor fabrication because of mirror reaction. Then, tungsten oxide is printed and sinter in 120oC as working electrode of a pH sensor. After fabrication, we connect the sensor to Jiehan 5600 Electrochemical Workstation to obtain the open circuit potential and the sensitivity of the pH sensor is -23.7 mV/pH.
Chieh-LunWu et 吳頡倫. « Fabrication and sulfidation/carbonization of 2D MOF nanoflakes-graphene oxide hybrid films as the electrode materials for all-solid-state supercapacitors ». Thesis, 2018. http://ndltd.ncl.edu.tw/handle/86qb78.
Texte intégralHuang, Pei-Chen, et 黃北辰. « Analysis and Investigation of Strain Engineering Utilized in 2D/3D Nano-scaled Germanium-based Metal Oxide Semiconductor Field Transistors Enabled by Column IV Semiconductor alloys ». Thesis, 2016. http://ndltd.ncl.edu.tw/handle/69394912930853497123.
Texte intégral中原大學
機械工程研究所
104
Currently, strain-engineering techniques are well established in Si-based metal–oxide semiconductor field-effect transistor (MOSFET)technology. To compensate for the drawback of device-size reduc-tion, germanium-substituted silicon is chosen as a channel material.Ge exhibits highly enhanced carrier mobility and it is regarded to be apromising channel material in a nano-scale MOSFET beyond the sub-22 nm technology node. This element has attracted considerable at-tention because of its potential to enhance the drive current of MOSFETsby replacing traditional strained Si-channel technology. Implanting Siatoms in the source/drain (S/D) region on the Ge substrate is a con-ventional method. Si and Ge atoms generate lattice mismatching,which improves device efficiency. Thus, this study adjusts the layout pattern of the device and usea 3D finite element model to simulate channel stress and mobility. Bycombining appropriate S/D stressors composed of Ge1 − x Six alloyswith the CESL at the considered intrinsic stress points, a significant en-hancement in the performance of tensile strained Ge-based nMOSFET can be acquired. Moreover, the strained GeSn alloy embedded into a Ge-based device is considered as a promising solution of next generation advanced devices. In contrast with Si, Ge, C in group IV semiconductor devices, GeSn alloy is indeed a novel material adopted in strained engineering. On the other hand, the arrangement of device layout also plays an important rule to influence device performance as S/D stressors are exerted. However, the analysis regarding comprehensive effects integrated GeSn stressors with the layout of that salient gate width extends across a dummy active diffused region (Dummy OD) is little. For this reason, a reliable device stress simulation is proposed and performed to explore the above-mentioned concerns under the vehicle consideration of a 20 nm Ge-based pMOSFET with a 100 nm gate width and a 100 nm dummy gate width. For the FinFETs layout design, the larger S/D region length and narrow channel length was suggested to enhance the longtidual stress of concerned channel.