WorldCat Identities

Sauvage, Rose-Marie

Overview
Works: 34 works in 36 publications in 2 languages and 43 library holdings
Roles: Opponent
Publication Timeline
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Most widely held works by Rose-Marie Sauvage
Development and understanding of III-N layers for the improvement of high power transistors by Romain Bouveyron( )

1 edition published in 2017 in English and held by 2 WorldCat member libraries worldwide

This thesis is mainly focused on the development of III-N materials for HEMTs power transistors, as well as quantum wells and optronics applications that result to a lesser extent. Following a reminder of the properties of nitrides, the different possible applications, the principle of the MOCVD and the different characterizations used for this work, we first treated the growth of GaN at low temperature, that is to say below 1050degres C. The manufacture of multiple quantum wells involving the alternation of GaN and InAlN or InGaAlN layers forces us to work at these temperatures, which generates the appearance of a defect in surface of the GaN which is called V-defect. An advanced experimental study allowed us to understand how these defects appear and evolve according to the growth parameters. A model based on surface energies could be developed and explains the evolution of these defects. Then we defined the influence of many MOCVD growth parameters by MOCVD and derived, from the multiple trends highlighted, the models and explanations justifying this or that physical and chemical property of the material. Downstream, these are electrical characterizations and mainly resistivity measurements that have been processed to compare the performance of our indium-based samples to those of AlGaN/GaN type. The problem of gallium pollution in vertical MOCVD reactors has been highlighted and we have proposed different solutions to limit or even annihilate it. Finally, we have tried to develop protective layers based on SiN and GaN in order to protect our indium-based alloys for the next technological steps required to manufacture a component, for example
Module wireless 60 GHz intégré en 3D sur silicium by Ossama El Bouayadi( )

1 edition published in 2015 in French and held by 2 WorldCat member libraries worldwide

L'évolution des nœuds technologiques dans l'industrie des semi-conducteurs se traduit de nos jours, dans le domaine des radiofréquences, par une miniaturisation des front-ends et une amélioration des performances électriques des émetteurs-récepteurs à des fréquences de plus en plus hautes. Cette évolution a conduit à la diversification des applications en bandes millimétriques (30 - 300 GHz) dans les secteurs des télécommunications, du divertissement multimédia, de l'automobile et de la sécurité. Plus particulièrement, le secteur des télécommunications connaît aujourd'hui une réelle révolution avec la création de nouveaux standards pour les liens sans-fil millimétriques à courte portée (comme WiGiG et IEEE 802.11ad) et l'apparition de nouvelles architectures basées sur des liaisons point-à-point qui constitueront dans les prochaines années la colonne vertébrale de la cinquième génération des réseaux mobiles. Dans le cadre de ces travaux de thèse, un intérêt particulier sera porté sur les modules intégrés sans fils et à faible consommation opérant dans la bande 57 - 66 GHz (dite généralement 60 GHz). A ces fréquences, la longueur d'onde en espace libre est comparable aux dimensions caractéristiques des boitiers standards utilisés pour l'encapsulation des transceivers. Il devient donc envisageable d'intégrer les antennes ainsi que d'autres composants passifs directement dans l'empilement technologique du circuit ou dans le boitier. Cette nouvelle génération de dispositifs électroniques, destinés au marché des terminaux portables, introduit de nouveaux défis en termes de performances électriques, de fiabilité mécanique, de coût et de possibilités d'industrialisation. Le packaging microélectronique joue dans ce cas un rôle principal dans la définition des performances globales du système qui s'étend au-delà de la simple protection de circuits intégrés pour couvrir d'autres fonctions d'intégration de divers dispositifs actifs et passifs. L'axe principal d'étude adopté ici porte sur le packaging d'un module SiP (System-in-Package) intégré en 3D et réalisé en technologie interposer silicium. Le mémoire de thèse s'articule en quatre chapitres : Le premier chapitre donne dans un premier temps une brève introduction aux bandes millimétriques et aux conditions de propagation spécifiques à ces bandes avant de présenter des exemples d'applications relevant de divers domaines civils et militaires. Ensuite, nous dressons un état de l'art des modules SiP millimétriques intégrés selon différentes approches technologiques. Le second chapitre est consacré à l'étude d'un module 60 GHz intégré sur silicium haute-résistivité en technologie interposer silicium. Nous nous intéressons aux méthodes de caractérisation adaptées aux diverses briques technologiques du back-end silicium spécifique aux applications RF-millimétriques et notamment les interconnexions, les matériaux diélectriques ainsi que les antennes intégrées. La caractérisation inclut également un test d'émission-réception entre deux modules 60 GHz. Dans le troisième chapitre, nous proposons d'améliorer le module grâce à un nouveau design d'antennes utilisant le concept de Surface Haute-Impédance (SHI). Ce design est destiné à octroyer plus de compacité et plus de fiabilité au module tout en conservant ses performances électriques. Finalement, le quatrième chapitre détaille les étapes de fabrication du véhicule de test antennaire ainsi que des résultats de caractérisation des antennes et des nouveaux matériaux diélectriques utilisés pour l'empilement technologique
Développement de procédés de nanostructuration sur films de polymères flexibles by Jérôme Durret( )

1 edition published in 2017 in French and held by 2 WorldCat member libraries worldwide

Les nanotechnologies représentent un potentiel de développements et d'applications considérables dans le domaine des matériaux ouvrant la voie à d'innombrables développements pour l'énergie, le transport, la santé, l'industrie, etc. Le biomimétisme a ainsi trouvé un nouveau moteur d'étude et de développement. La feuille de lotus est capable de faire perler l'eau avec une efficacité remarquable transformant n'importe quelle goutte d'eau en une bille répondant aux lois de la physique des solides. Cette propriété extraordinaire est due à l'association d'une composition chimique intrinsèquement hydrophobe avec une texturation hiérarchique de sa surface.Cette thèse s'intéresse à la compréhension des principes physiques qui régissent l'interaction des gouttes d'eau avec les surfaces de films polymères structurées de FEP, PMMA et PET. Deux technologies ont été mises en oeuvre pour la fabrication de surfaces superhydrophobes hiérarchiques : la nanoimpression (NIL) thermique et la gravure plasma. Nous avons mesuré les angles de contact et hystérésis de ces surfaces structurées afin d'identifier leur état de mouillage de Wenzel ou de Cassie-Baxter. Nous avons attaché une importance particulière au développement de solutions de fabrication et de caractérisations sur de grandes surfaces.Les propriétés antigivre ont été caractérisées, ainsi le rôle de la condensation dans la propagation du givre a été corrélé à la structuration de surface. De plus, nous avons mis en évidence le rôle du potentiel électrostatique de surface sur les retards de gel. Enfin, au vue du potentiel applicatif de ces surfaces, nous avons ajouté une dimension dynamique à l'étude en considérant les vitesses d'impact des gouttes. Un modèle de prédiction de la littérature a été comparé avec succès aux résultats expérimentaux
Microsystèmes de stockage d'énergie sur substrat 3D by Etienne Eustache( )

2 editions published in 2016 in French and held by 2 WorldCat member libraries worldwide

Providing autonomy to miniaturized electronic devices is a challenge. New research directions should be investigated in order to increase the performance of Liion microbatteries (MB) and micro-supercapacitors (MSC). Developing power sources with a 30 topology instead is a promising approach to surpass the planar devices energy density. ln this exploratory thesis, we realized 30 structures at the micrometric scale by deep etching of a silicon substrate. This architecture is used as a common base to fabricate Li-ion MB and MSC. A TiO2 MB negative electrode has been realized by atomic layer deposition (ALD) on top of the microstructures. Electrochemical characterizations show a proportional increase (x30) of the capacity with the specific surface area of the 30 architecture. A conformal lithium phosphate (Li3P04) film has also been developed by ALD. The ionic conductivity (=4.10-7 S/cm) and the limited thickness (60 nm) of the layer establish this material as a 30 MB potential solid-state electrolyte. Furthermore, MSC with interdigitated 30 electrodes have been fabricated. Mn02 thin films have been deposited by electrodeposition on top of the 30 substrate. Results demonstrate that this approach allow to achieve pseudocapacitive devices with high specific capacitance
Matériaux magnétostrictifs de nouvelle génération pour l'énergie by Valentin Issindou( )

1 edition published in 2017 in French and held by 2 WorldCat member libraries worldwide

In recent years, performances of multiferroïc materials have considerably improved with two-phase composites: magnetostrictive and piezoelectric. These composites take advantage of the coupling between magnetism and piezoelectricity through magnetostriction. Thus they allow control of magnetization with electrical voltage, and conversely, to get an electrical polarization depending on the magnetic field (our focus in this case). This drives electronics towards more environmental friendly solutions, namely with lower circuit power consumption (current controls are replaced by voltage controls) and the replacement of batteries, which must be periodically changed, by sustainable energy harvesting systems. Energy harvesting solutions are popular with the Internet of Things (IoT). Despite their performance, these multiferroïc composites remain perfectible, especially regarding the magnetostrictive phase. Its optimization is essential. The common material is Terfenol-D because of its giant magnetostriction, used in its massive and monocrystalline form. This material remains rare, expensive, fragile and its growing method is not adapted to the manufacturing of miniature devices. This work focuses on a comparative study of Terfenol-D miniature disk manufacturing pathways for the production of energy harvesters. A benchmark study was carried out on a series of disks cut in commercial alloy ingots (monocrystalline and polycrystalline). Next, the isotropic powder sintering method was investigated with very little background on this material. Conventional sintering led to the first functional disks needing no ulterior machining but with low density and mechanical strength. These defects were then corrected using the SPS technique (Spark Plasma Sintering) but the reproducibility over time has yet to be improved. The Terfenol-D disks (both cut and manufactured) were assembled with the piezoelectric phase (commercial PZT). Electrical characterizations using a contactless method have validated their potential to harvest energy, in lesser amounts than monocrystalline Terfenol-D as expected, but in a large enough quantity regarding most of applications. Finally, an alternative solution has been explored with NiMnGa shape magnetic alloys offering very large deformations. A perspective to a wireless autonomous push button prototype is presented at the very end
Conception de circuit intégré pour les applications gravimétriques basées sur l'utilisation de résonateurs mécaniques arrangés en réseau by Guillaume Gourlat( )

1 edition published in 2017 in French and held by 2 WorldCat member libraries worldwide

The extreme sensitivity of nano electro mechanical system (NEMS) to atomic scale physical variations has led to the breakthrough development of NEMS- based mass spectrometry sys- tems capable of measuring a single molecule. Parallel sensing using thousands of devices will help to circumvent the small effective sensing area while opening new perspectives for applica- tions which require spatial mapping. While the development of NEMS CMOS co-integration technology is of paramount importance to achieve high density sensor arrays (>1000 devices), the readout circuitry capable of tracking NEMS resonator frequency shifts is still the limiting factor for the very large scale integration of individually addressed sensors. Moreover, in order to resolve the mass and position of an adsorbed analyte, single particle mass sensing appli- cations require to track simultaneously and in real time at least two modes of the resonators. This requirement adds complexity to the design of the overall system. To respond to the size, power consumption and resolution constraints linked to NEMS array measurement, this work focuses on the development of a new readout architecture based upon a dual mode heterodyne oscillator. This work also emphasis the effort made on the modelization and co-simulation of the NEMS devices with their readout electronics. Then, the manuscript describe the first results of the CEA/LETI CMOS co-integraton process developed to tackle the sensor density challenge of mass spectrometry application. Finally, present the two integrated circuit that were designed during this thesis. The first one was a proof of concept for the aforementioned oscillator architecture while the second one combine the architecture with the co-integration processus developed
Développement et optimisations d'un nez électronique basé sur l'imagerie de résonance de plasmons de surface by Sophie Brenet( )

1 edition published in 2018 in French and held by 2 WorldCat member libraries worldwide

Electronic noses are promising candidates for low-cost field monitoring of volatile organic compounds (VOCs). However, these techniques are still challenged with limitations. The use of a limited number of receptors prevents selective VOCs differentiation. A lack of reliability caused by pollution of receptors hinders their use for many applications. In this context, an electronic nose based on surface plasmon resonance imaging (SPRI) is developed for the detection of VOCs in the gas phase. This system consists of a broad array of receptors obtained by the self-assembly of organic molecules and peptides. SPRI optical transduction provides multiplexed monitoring of a large number of interactions in real time. The objective is to ensure the best possible chemical resolution to reliably differentiate VOCs. To this end, different strategies are explored to improve the sensitivity, selectivity and stability of the measurements. Thanks to these optimizations, our system offers a high selectivity for a large number of VOCs. VOCs are differentiated according to their chemical nature and structure. A good repeatability and a stability of at least two months are obtained. Preliminary tests show that our instrument is also effective for the analysis of more complex samples
Antenne à cristal photonique électro-optique pour la détection de fréquences électromagnétiques by Venancio Calero Vila( )

2 editions published in 2017 in English and held by 2 WorldCat member libraries worldwide

This thesis work focuses on the fabrication of non-perturbing E-field sensors based on the electro-optical effect. Lithium niobate (LiNbO3) combined with Photonic Crystals (PhC) can increase considerably the material sensitivity to electric fields leading to ultra-compact devices. The target structure must exhibit a high sensitivity, extended bandwidth, ultra-fine spatial resolution and the most important: the electric field should not perturb the electric field to be measured, which is ensured since the sensor is not based on metallic parts. Most of the E-field sensors based on ferroelectric materials are based on Mach-Zehnder (MZ) modulators or any other kind of waveguide-based topologies which presents high losses produced at the injection of the light within the tiny waveguides and can reach relatively low electric field sensitivities. These issues may not happen in fibered-based devices where the photonic structure can be located at the facet and a nano-structure may act as a sub-wavelength diffraction grating that couples the light into the PhC itself. By choosing the adequate geometrical parameters, very efficient out-of-plane to in-plane coupling can be performed.In this thesis we focus on the simulation, fabrication and characterization of the fiber-tip electric-field sensor. Here we perform numerical simulations in order to study the feasibility of the structure where the different fabrication errors are studied. The fabrication is divided in two parts: a first one where we overcome with the problem of micromachining photonic crystals within Thin Film Lithium Niobate (TFLN) and a second part, where the integration of the photonic device within the fiber facet is explained. Regarding the part concerning the PhC fabrication, we have developed a reproducible process to release the lithium niobate membrane where the PhC is made by Focused Ion Beam (FIB) techniques. The optical characterization of these structures, which receive the name of Photonic Crystal Slabs (PCS), shows excellent agreement with the theory never achieved before in this material. On the other side, different methods here shown for the integration onto fiber, leading to an ultra-compact and versatile sensor. After the assembly, the sensor is characterized verifying its different features such as spatial resolution, linearity, sensitivity and bandwidth. The resulting device results in the first Fano E-field sensor ever reported, but in addition it also presents the highest spatial sensitivity ever obtained in these kind of devices
Matériaux à base de nanocristaux semi-conducteurs de chalcopyrite pour la conversion thermoélectrique by Louis Vaure( )

1 edition published in 2017 in French and held by 2 WorldCat member libraries worldwide

This thesis presents the studies made on semiconducting nanocrystals, to be integrated in thermoelectric generators. Thermoelectricity generates a current through a temperature difference between two faces, connected by thermoelectric legs which conduct the charges. Nowadays, the most efficient materials at room temperature contains tellurium, which is toxic and expansive due to its scarcity. A study on theory and literature is carried to understand the underlying phenomena which help us explain the thermoelectric conversion. The potentially interesting materials are selected for their cost and efficiency, tunable by varying different parameters. Chalcopyrite, of formula CuFeS2, presents promising properties for thermoelectricity, and offers an interesting way to replace classic materials as a non-toxic earth-abundant substitute. The chemical synthesis allows to control the composition of the material and to obtain 30 to 50 nm sized nanocrystals, able to scatter phonons and diminish the thermal conductivity of the material as a consequence. The thesis is describing the study of these semiconducting CuFeS2 nanocrystals, and is divided in two main parts.The first part describes the chemical synthesis of the nanocrystals and the characterization of their structure. Two ways of synthesis are developed and optimized, allowing to control the stoichiometry of the material, and to obtain crystals of different sizes and shapes. A complete study of the composition of the nanocrystals is made by XPS, EDX and thermogravimetric analysis. The study of the material by X-ray diffraction shows that the chemical composition of the nanocrystals, as well as the temperature and the pressure, have an influence on their crystalline phase. A phase transition from the wurtzite phase to the chalcopyrite phase is described.In the second part, are studied the thermoelectric properties of the nanocrystals. Their preparation as solid materials is described. The improvement made on their efficiency is following three main paths. The obtained material is a n type conductor, which means it carries electrons. Its thermal conductivity is reduced due to the nanostructuration. The first strategy consists in varying the composition of the nanocrystals, and especially the ratio between positive and negative charges, carried by ions, to modify the electrical conductivity and Seebeck coefficient of the material through doping. The second way of improvement is by replacing the native insulating ligands of the nanocrystals by short inorganic conducting ones, to increase the electrical properties of the material. Finally, metallic nanoparticles, of silver, tin and copper, are blended with the nanocrystals to improve the electrical conductivity of the resulting nanocomposite material.This thesis helps one to understand the relation between structure, composition and thermoelectrical properties of ternary semiconducting materials. It is possible to think of ways of improvement for the studied materials. Our best results are state of the art for this family of materials, especially around room temperature. There is room for improvement, with a proper combination of the studied parameters. During a future work, the optimized material could be integrated to a thermoelectric - photovoltaic device, for conversion of the solar energy through the two phenomena
Nanostructures métalliques et effets de composition des verres silicatés pour les capteurs à fibres optiques by Simon Degioanni( )

1 edition published in 2015 in French and held by 1 WorldCat member library worldwide

The purpose of this thesis is to study composition variations of silicate glasses or the integration of metallic nanostructures that may be relevant for distributed fiber optic sensors (FOS). These sensors use optical fiber cores mainly composed of silica (SiO2) to probe temperature or strain on multi-kilometer route fibers. To measure these effects, Raman and Brillouin backscattering in optical fibers are used, Raman scattering being sensitive to temperature variations and Brillouin scattering to temperature and strain variations. Raman scattering intensity may be enhanced in conjunction with noble metal nanostructures via the SERS effect (Surface Enhanced Raman Scattering) which involves surface plasmon resonance (SPR), a collective oscillation of free electrons at the metal surface generating a large amplification of the local electric field. The integration of metallic nanostructures in optical fibers could increase Raman backscattering intensity and improve FOS performance (sensitivity, integration time...). A study on model samples has been performed with SERS substrates consisting of gold nanostructures and coated with a sol-gel oxide deposition (TiO2, SiO2). The obtained SERS results are used to predict the contribution of metallic nanostructures in Raman distributed temperature FOS
Prototypage d'un objet volant mimant l'insecte by Alexandre Bontemps( )

1 edition published in 2013 in French and held by 1 WorldCat member library worldwide

Ce travail de thèse s'inscrit dans le contexte des drones vise à réaliser à terme un Nano-dispositif volant (Nano Aerial Vehicle) capable d'imiter le vol des insectes. Ce mode de locomotion est privilégié car il présente des caractéristiques très adaptées au vol en milieu confiné. La solution proposée consiste à développer un drone de la taille d'un insecte s'appuyant sur des ailes vibrantes pour se mouvoir et à utiliser les technologies MEMS pour répondre aux problématiques de fabrication et de réduction d'échelle. La réussite d'un tel projet soulève néanmoins de nombreux défis scientifiques et technologiques, en particulier, les aspects aéro-élastiques des ailes et l'autonomie du drone. Pour répondre à ces défis, nous proposons dans un premier temps de mettre en œuvre des concepts comme la résonance et la torsion passive sur des prototypes en polymère (SU-8) réalisés par photolithographie. Dans un second temps, les différents composants de la chaîne de puissance sont optimisés, notamment l'actionneur électromagnétique, la liaison et les ailes de manière à maximiser la force de portance générée. Suite à ces améliorations, nous démontrons de façon expérimentale que le prototype était capable non seulement de reproduire une cinématique complexe mais également de compenser 75% de son poids
Capteurs à ondes élastiques confinées, sans fil et étirables : application à l'électronique imperceptible sur peau by Cécile Floer( )

1 edition published in 2019 in French and held by 1 WorldCat member library worldwide

Avec le développement des objets connectés et de l'IoT (Internet of Things), le suivi en continu des paramètres corporels et la miniaturisation extrême des équipements de mesures deviennent de réels enjeux de société. Parallèlement, les dispositifs à ondes élastiques de surface (dispositifs SAW), largement utilisés dans les télécommunications pour leur propriété de filtrage, connaissent aujourd'hui un essor pour leur fonction de capteur. C'est précisément dans ce contexte, à l'interface entre l'électronique sur peau et la micro-acoustique que se situe ce sujet de thèse. L'objectif est de développer un capteur de température sans fil qui associe un dispositif basé sur la technologie des ondes élastiques à des antennes étirables. L'utilisation d'une structure à ondes confinées (WLAW) et un choix de matériaux appropriés permettent ensuite de supprimer le besoin d'encapsulation du dispositif. Au format ultrafin et ultrasouple, l'ensemble peut être « tatoué » harmonieusement sur la peau. Une grande partie du travail est consacrée à l'élaboration de dispositifs autoprotégés et à leur optimisation par le biais de différentes stratégies (développement de matériaux en couches minces, designs). L'interrogation à distance est démontrée en utilisant des antennes étirables réalisées par transfer printing
Étude des propriétés non-linéaires et de l'origine du bruit d'oscillateurs à transfert de spin à base de vortex : vers le développement de nano-dispositifs radiofréquences spintroniques by Eva Grimaldi( )

1 edition published in 2015 in French and held by 1 WorldCat member library worldwide

The main goal of this thesis is the understanding of the physical mechanisms and the subsequent control of the properties at the origin of the spin transfer induced magnetic vortex gyrotropic motion in confined systems. In particular the origin of the noise affecting the dynamics has been investigated. This work has been performed with a view to improving the radiofrequency (rf) properties of the so-called Spin Transfer Oscillator (STO).The advantages of such oscillators are their sub-micron size (from few tens to hundreds of nanometres), their compatibility with CMOS technologies and their radiation hardness. Moreover, the magnetization dynamics involved permit a large tunability of frequency as a function of the applied current and a high agility i.e. a fast dynamical response. Nevertheless, several open questions exist regarding the possible optimization of the sustained oscillation conditions and the improvement of the STO power and spectral coherence.The first aspect of my work was to investigate the influence of thermal fluctuations over the sustained vortex core gyrotropic motion. One of the key results of my thesis was to show that the phase noise results from direct phase fluctuations from thermal fluctuations plus amplitude fluctuations converted to phase noise. With an analytical model, we were able to highlight the major role played by the non-linearities of the forces acting on the vortex core. In addition, we were able to measure the characteristic parameters of the oscillator, namely, the speed of frequency response to perturbations as well as the phase-amplitude coupling coefficient.The second important part of my work has been to improve the conditions for obtaining an rf signal. An important result of this work was the measurement of a powerful rf signal in the absence of a magnetic field. The measured powers are a few hundred milliwatts and correspond to low linewidths, ranging from a few hundred kilohertz to a few megahertz. The zero field behaviour was made possible due to the complex structure of the oscillator where the magnetic layer which polarizes the spin current has a perpendicular magnetization, in contrast to the in-plane polarized reference layer.The third step was to optimize the performance of the oscillator. One of the striking results of this thesis is that we measured a record rf output power, up to 3.6 µW, the largest obtained at room temperature for vortex based STOs so far. This high output power results from the development of new FeB based junctions made by the group of Pr. S. Yuasa (AIST, Japan), where the improvement of the quality of the junction allowed us to obtain a magnetoresistance up to 125%.The small size of the oscillator has a cost that is paid in terms of the phase noise. One possible solution that would solve this limitation and enhance the coherence of the oscillations is via mutual synchronization of several STOs through rf currents emitted by each oscillator. Thus, the last stage of my thesis was to study the behaviour of gyrotropic motion when subjected to an alternating current. An important result was to show, through an experimental study in conjunction with an analytical model, the crucial role of the non-linearities and symmetries of the synchronization forces.These various studies have provided us the tools to better understand the dynamics of magnetic vortex and led us to develop an original tester for which the oscillator synchronizes itself with its own rf signal. Depending on the delay at which the oscillator is fed back, we showed for the first time that the frequency, the power and also the linewidth of the oscillations can be modulated
Dynamique d'ondes de spin dans des microstructures à base de films de YIG ultra-minces : vers des dispositifs magnoniques radiofréquences by Martin Collet( )

1 edition published in 2017 in French and held by 1 WorldCat member library worldwide

Modélisation, réalisations et caractérisations optiques de couches hétérogènes à nanoparticules by Miriam Carlberg( )

1 edition published in 2017 in English and held by 1 WorldCat member library worldwide

Les nanoparticules (NPs) de métaux nobles ont de nombreuses applications grâce à leurs propriétés optiques, chimiques et électriques extraordinaires. Les propriétés optiques résultent de plasmons localisés de surface, exaltant l'absorption et la diffusion de la lumière aux longueurs d'onde de résonance dans le domaine du visible. Les propriétés optiques, dépendantes de la taille et de la forme exacte de la NP, sont mises à profit dans l'objectif de créer un absorbant parfait en couche mince. Les applications de ces couches minces concernent, parmi d'autres, les photodétecteurs, le solaire thermique et les applications de furtivité.Les récents progrès accomplis dans le domaine des synthèses colloïdales de NPs nous permettent de synthétiser des nanosphères, nanocubes et nanoprismes d'Ag de différentes tailles. Ces NPs sont déposées aléatoirement dans une matrice hôte non-absorbante afin d'être caractérisées optiquement. Les résultats expérimentaux sont validés à l'aide de calculs numériques, permettant en outre de visualiser les phénomènes physiques à l'échelle de la NP.Cette thèse décrit les synthèses chimiques et les caractérisations optiques. Des mesures de spectroscopie ellipsométriques sont effectuées sur différentes couches minces. Un modèle optique simple, constitué d'une loi de Cauchy et d'une ou plusieurs lois de Gauss, est dérivé afin d'obtenir les indices optiques complexes de nos échantillons. La comparaison des coefficients d'extinction des différentes couches montre que les propriétés optiques de chaque NP sont additionnées en mélange et en empilement. Les calculs numériques relient ce résultat à la faible densité de nanoparticules en couche
Déplacement de paroi de domaine par transfert de spin dans des jonctions tunnel magnétiques : application au memristor spintronique by Steven Lequeux( )

1 edition published in 2016 in French and held by 1 WorldCat member library worldwide

In the current context of information technology, the sequential processing carried out by classical computer architectures stumbles on problems of energy consumption. Inspired by nature, especially the brain, an alternative solution appears through artificial neural networks. In this background, the realization of nano-components, called memristors, which mimic synaptic plasticity, enables to consider achieving densely interconnected neural networks due to their small size. In this work, our focus is on the realization of such a component, defined as a tunable and non-volatile nano-resistor, and which operation is based on the principle of spintronics (use of the spin of electrons as information vector), which has the advantages of compatibility with current technologies (CMOS, MRAM ...etc). By using a magnetic tunnel junction, the concept of the spintronic memristor is based on the motion of a magnetic domain wall by spin transfer effect, where each wall position defines an intermediate resistance state. In order to control the resistance of this spintronic memristive device, the study of static and dynamic properties of the domain wall under the influence of a spin polarized current is required. By the study of the displacement and resonance of the wall whithin an in-plane magnetized device, we established a first assessment (commutation time of the device below one nanosecond and observation of an over-damping). Based on these preliminary studies, we then optimized magnetic tunnel junctions with out-of-plane magnetizations. On one hand, we show that the number of intermediate resistance states is strongly increased (between 15 and 20 states), allowing this spintronic memristive device to be used to perform neuromorphic tasks. Furthermore, we show that the device is optimized to use the most efficient spin transfer torque to displace the magnetic domain wall
Nano-antennes plasmoniques avec des diodes moléculaires rectifiantes pour la captation d'énergie et la photodétection : synthèse de dérivés de ferrocène par chimie click fonctionnant comme diodes moléculaires pour application rectenna by Damien Brunel( )

1 edition published in 2020 in French and held by 1 WorldCat member library worldwide

The sun is an unlimited source of power and seems to be a perfect solution for the fight against global warming. However, this last years, the efficiencies associated to the photovoltaic technologies are moderate (< 50 %). Considering the wave-particle duality, it is possible to use the wave properties of the light in order to produce electricity. Such object called rectenna solar cells was described theoretically in the 70s. The rectenna consists in the association of an antenna with a diode. Experimental realisation of rectenna was impossible in the 70's. Recently innovative design of rectenna solar cells at IM2NP was developed. The diode element in such design was not deeply studied. The subject of this PhD is the synthesis and characterisation of these diodes. It is ferrocene based molecular diodes, so where the molecules act as a diode. They are pioneering since it is possible to anchor them to two different metal surfaces in controlled way. Such control is done by a reaction on the metal surface. The reaction chosen belongs to the click chemistry. The subject of this PhD is the synthesis and the fabrication of molecular diode on metal surface in controlled way. First by describing the rectenna and their components. Secondly describing the tools used in the project to realize the diode. Then the different synthesis of the new ferrocene based molecular diode will be presented. Finally, the characterisation and the fabrication of the diode on real devices will be discussed. This PhD has a multidisciplinary aspect where chemists and physicists work together in order to create an object in technological rupture in technology of production of electricity
Printable and printed perovskites photovoltaic solar cells for autonomous sensors network by Alexandre Gheno( )

1 edition published in 2017 in English and held by 1 WorldCat member library worldwide

This thesis is about the design of photovoltaic solar cells based on hybrid perovskite using inkjet printing technology. The first two chapters present the context of the thesis, namely the powering of an autonomous sensor network, and review the scientific aspects of inkjet and photovoltaic technologies. The third chapter presents the development of a state-of-the-art photovoltaic cell and its evolution towards a printable architecture at low annealing temperatures. The problem of the stability of photovoltaic cells with perovskite is also discussed. The last part presents the different aspects and problems of the inkjet printing of the three inner layers of a perovskite solar cell. At the end of this work the possibility of printing perovskite solar cells with efficiencies higher than 10% has been demonstrated, all in ambient conditions and at low temperature
Textiles de protection fonctionnalisés auto-décontaminants vis-à-vis d'agents chimiques associant des propriétés photocatalytiques et d'adsorption/filtration by Pauline Barrois( )

1 edition published in 2018 in French and held by 1 WorldCat member library worldwide

This project is focused on the elaboration of protective suits against Chemical Warfare Agents. Indeed, the suits currently used mainly act as physical barriers, without any degradation of the toxic molecules, thus increasing cross-contamination risks.The original idea is to functionalise textile fibers with a multifunctional, multicomponent and transparent smart layer, combining active components (TiO2, for photo-oxidation of toxic agents under irradiation at room temperature) to passive components (carbon nanostructures, in order to temporary stock the reaction products or the contaminant in case of lack of irradiation or of high contamination level). The study begins on model surfaces, in order to optimise Layer-by-Layer (LbL) association of TiO2 with polymer, graphene, activated carbon, or nanodiamonds. The photocatalytic efficiency of the layer was evaluated towards the degradation of a gaseous mustard gas simulant. The best functionalisations were then transferred to textile and their photocatalytic efficiency were evaluated towards the degradation of a liquid simulant of Sarin gaz. Some detailed results were obtained in order to understand the impact of the different components and of the thickness of the films on the activity. Textiles reinforcement against abrasion and washing were also studied, as well as their regeneration after photocatalytic tests
Réponse dynamique d'un nano-oscillateur spintronique à un signal rf pour le développement de nouveaux détecteurs rf ultra-miniatures by Samh Menshawy( )

1 edition published in 2019 in French and held by 1 WorldCat member library worldwide

Spintronic nano-oscillators have remarkable properties in terms of radio frequency detection. Their nanoscale sizes, room temperature operation, and CMOS compatibility make them serious candidates for providing instantaneous spectral analysis in embedded systems. This thesis concerns the detection properties of magnetic vortex-based STNOs. One of the effects conferring on STNOs the possibility of detecting a rf signal is the spin diode effect. An rf source is used to create the signal to be detected. When the rf current frequency injected into the STNO corresponds to its resonant frequency, a rectification voltage is created at its terminals. The measurement of this voltage by a simple voltmeter makes possible to determine the rf current presence. The evolution study of the resonance frequency as a function of the STNO radius, the dc current and the magnetic field has highlighted the possibility of choosing the resonant frequency and tuning it with these parameters. From an application point of view, this property is essential for allocating an STNO to a specific frequency to be detected. Furthermore, the STNO nanometric allows us to envisage a network of thousands, even millions of STNOs contained on a chip operating at ambient temperature. However, several problems arise. The STNO sensitivity to an external rf signal must allow to determine the occupancy state of a frequency channel by a simple measurement of the voltage or with a voltage comparator. This requires a voltage variation of ten mV order. The spin diode effect doesn't allow to achieve such variation. Another effect, measured for the first time at the Unité Mixte de Physique CNRS/Thales, called magnetic vortex expulsion, is studied. This phenomenon occurs when the vortex core crosses the STNO edges during its spin transfer induced dynamics. Thanks to this effect, the voltage amplitude variation can reach up to 25 mV in the STNOs characterized during this thesis. Moreover, this phenomenon can be tuned. From an application perspective, a network of STNOs must be created in order to allocate an STNO to a specific frequency range and thus cover a broad frequency band.The rf current distribution to all STNOs is therefore a problem to which we have brought a solution. The excitation of the vortex core by a rf field allows us to excite a large number of STNO thanks to an inductive line lithographed above the STNOs. The possibility of expelling the vortex core under these conditions has been demonstrated. We then studied the vortex core dynamics induced by an rf field during the expulsion. A time and frequency domain studies not only provided us detection time information of an rf signal by the STNO but also on its magnetization in the expulsion regime. Moreover, the STNO frequency tuning is possible even when the vortex core is excited by an rf field. Finally, these studies enabled us to implement step by step a proof of concept demonstrating the rf detection feasibility with spintronic nano-oscillators. The various studies of vortex core expulsion combined with a considerable technical work of design and manufacture finally allowed us to converge towards a solution that constitutes a starting point towards the development of a broadband spintronic spectrum occupancy detector, contained on a chip and operating at room temperature
 
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