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Étude détaillée des dispositifs à modulation de bandes dans les technologies 14 nm et 28 nm FDSOI / Detailed Investigation of Band Modulation Devices in 14 nm and 28 nm FDSOI TechnologiesEl dirani, Hassan 19 December 2017 (has links)
Durant les 5 dernières décennies, les technologies CMOS se sont imposées comme méthode de fabrication principale pour les circuits semi-conducteurs intégrés avec notamment le transistor MOSFET. Néanmoins, la miniaturisation de ces transistors en technologie CMOS sur substrat massif atteint ses limites et a donc été arrêtée. Les filières FDSOI apparaissent comme une excellente alternative permettant une faible consommation et une excellente maîtrise des effets électrostatiques dans les transistors MOS, même pour les nœuds technologiques 14 et 28 nm. Cependant, la pente sous le seuil (60 mV/décade) du MOSFET ne peut pas être améliorée, ce qui limite la réduction de la tension d’alimentation. Cette restriction a motivé la recherche de composants innovants pouvant offrir des déclenchements abrupts tels que le Z2-FET (Zéro pente sous le seuil et Zéro ionisation par impact), Z2-FET DGP (avec double Ground Plane) et Z3-FET (Zéro grille avant). Grace à leurs caractéristiques intéressantes (déclenchement abrupte, faible courant de fuite, tension de déclenchement ajustable, rapport de courant ION/IOFF élevé), les dispositifs à modulation de bandes peuvent être utilisés dans différentes applications. Dans ce travail, nous nous sommes concentrés sur la protection contre les décharges électrostatiques (ESD), la mémoire DRAM embarquée sans capacité de stockage, et les interrupteurs logiques. L’étude des mécanismes statique et transitoire ainsi que des performances de ces composants a été réalisée grâce à des simulations TCAD détaillées, validées systématiquement par des résultats expérimentaux. Un modèle de potentiel de surface pour les trois dispositifs est également fourni. / During the past 5 decades, Complementary Metal Oxide Semiconductor (CMOS) technology was the dominant fabrication method for semiconductor integrated circuits where Metal Oxide Semiconductor Field Effect Transistor (MOSFET) was and still is the central component. Nonetheless, the continued physical downscaling of these transistors in CMOS bulk technology is suffering limitations and has been stopped nowadays. Fully Depleted Silicon-On-Insulator (FDSOI) technology appears as an excellent alternative that offers low-power consumption and improved electrostatic control for MOS transistors even in very advanced nodes (14 nm and 28 nm). However, the 60 mV/decade subthreshold slope of MOSFET is still unbreakable which limits the supply voltage reduction. This motivated us to explore alternative devices with sharp-switching: Z2-FET (Zero subthreshold slope and Zero impact ionization), Z2-FET DGP (with Dual Ground Planes) and Z3-FET (Zero front-gate). Thanks to their attractive characteristics (sharp switch, low leakage current, adjustable triggering voltage and high current ratio ION/IOFF), band-modulation devices are envisioned for multiple applications. In this work, we focused on Electro-Static Discharge (ESD) protection, capacitor-less Dynamic Random Access Memory and fast logic switch. The DC and transient operation mechanisms as well as the device performance are investigated in details with TCAD simulations and validated with systematic experimental results. A compact model of surface potential distribution for all Z-FET family devices is also given.
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Strain-engineering of thin polymer films : a novel route for the development of functional materials and microfluidic devices / Ingénierie des contraintes de films minces de polymères : une nouvelle voie pour le développement de matériaux fonctionnels et d'outils microfluidiquesEgunov, Aleksandr 23 November 2015 (has links)
Les deux systèmes de création d’une contrainte dans les films polymériques ont été développés, chacun répondant à un gradient de gonflement du polymère dans la direction normale au film. Ce gonflement peut être provoqué soit par la présence d’un gradient de densité de réticulation dans la direction normale à la surface (films de poly(4-vinylpyridine) réticulés par UV ou dans les films de chitosan réticulés thermiquement et ioniquement ; ou soit par une pénétration asymétrique de vapeur de solvant dans le film (ici le polydiméthylsiloxane oxydé en surface). Un troisième système polymérique auto-enroulant a également été réalisé par la création d’une contrainte permanente au sein du film de polydiméthylsiloxane, grâce à l’extraction sélective d’un additif non-réticulé, l’huile de silicone. Un modèle théorique du processus d’auto-enroulement, basé sur la théorie linéaire d’élasticité a ainsi pu être proposé. / Two systems of stress creation in the polymer films were developed, each based on the swelling gradient in the direction normal to the film. This swelling may be caused either by the presence of a crosslinking density gradient in the direction normal to the surface (poly (4-vinylpyridine film) crosslinked by UV or in the thermally or ionically crosslinked chitosan films; or by asymmetric penetration of solvent vapor in the film (here polydimethylsiloxane surface-oxidized). A third self-rolling polymeric system has also been realized by the creation of a permanent strain in the polydimethylsiloxane film by selective extraction of a non-cross-linked additive, silicone oil. A theoretical model of self-rolling process based on the linear theory of elasticity has been proposed.
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Etude des transistors en couches minces à base d’IGZO pour leur application aux écrans plats à matrice active LCD et OLED / Study of thin film transistors based on Indium Gallium Zinc Oxide for their applications in active matrix flat panel LCD and OLED displayNguyen, Thi Thu Thuy 12 November 2014 (has links)
Ce travail de thèse a pour sujet l'étude de transistors en couches minces (TFTs) à base d'Indium Gallium Zinc Oxide (IGZO). Nous nous sommes intéressés au procédé de réalisation des TFTs, et à la caractérisation des couches d'IGZO afin d'obtenir les caractéristiques au plus près de l'état de l'art. Nous avons également étudié le processus de passivation, paramètre identifié comme critique pour stabiliser les TFT et atteindre de bonnes performances.Dans un premier temps, nous avons mis au point les conditions du dépôt de la couche active, et de la réalisation des TFTs. Les analyses morphologiques et structurales ont montré l'absence de cristallites de couche, ainsi qu'une surface peu rugueuse. La densité des porteurs de charge de la couche IGZO diminue lorsque le débit d'oxygène, variable durant son dépôt, augmente. La couche active déposée à 200°C et à 4 sccm d'oxygène présente une densité de porteurs de charge de l'ordre de 1E17 cm-3, valeur adaptée au fonctionnement des TFTs.Dans un second temps, nous avons évalué l'influence d'un recuit sur les caractéristiques des TFTs. Nous avons mis en évidence que le recuit sous oxygène conduit à des TFTs opérationnels, tandis que celui sous azote ou en absence de recuit induisent une suppression de l'effet de champ. Nos études ont également montré qu'une température de recuit de 300°C est favorable aux performances des transistors. Les premiers TFTs présentent des mobilités entre 5 et 15 cm2/Vs, des rapports ION/IOFF de l'ordre de 1E7, et des pentes sous le seuil d'environ 0.3 V/décade. Les tensions de seuil (VT), quant à elles, demeurent faibles donc restent à améliorer.Pour finir, nous avons étudié l'impact d'une couche de passivation sur les TFTs, en raison de la dégradation des caractéristiques de ces derniers dans l'atmosphère ambiante. Les couches de SiO2 (déposée par PECVD) et d'Al2O3 (déposée par ALD) ont été étudiées. Nous avons mis en évidence que ces passivations peuvent dégrader les TFTs au lieu de les protéger. VT tend à se décaler dans le sens négatif lorsque l'on augmente l'épaisseur de la couche d'Al2O3 ou le débit de Silane durant le dépôt du SiO2. Une des raisons principales de ce phénomène est la présence de l'hydrogène généré lors de la passivation. Nous avons évalué les solutions pour éviter la dégradation lors du dépôt et assurer une bonne protection du TFT. / This thesis aims to study thin-film transistors (TFTs) based on Indium Gallium Zinc Oxide (IGZO) in the framework of applications in active matrix flat panel LCD and OLED display. The TFT fabrication process and the characterization of IGZO deposited film are two key studies in this thesis in order to obtain TFT electrical characteristics close to the state-of-the-art. We have also studied the passivation which is identified as crucial for stabilizing the TFT and achieving good performance.The deposition of the active layer and the fabrication process of TFT are firstly studied. Smooth surface of deposited films is demonstrated by AFM and the absence of the crystalline peak of the material is shown by X-ray diffraction. The density of charge carriers decreases with the increase of oxygen flow rate. The active layer deposited at 200°C and at 4 sccm of oxygen flow has a carrier density in the order of 1E17 cm-3 which is suitable for TFT operation. This condition is chosen to fabricate IGZO-based TFT in this thesis.In a second step, we have evaluated the influence of annealing condition on TFTs' electrical characteristics. Annealing in oxygen leads to operational TFTs while doing the same under nitrogen or the absence of annealing suppresses field-effect behavior. Our studies have also shown that annealing temperature of 300°C is suitable to obtain good performance of the transistors. From this study, we have obtained TFTs with high mobility (between 5 and 15 cm2/Vs), high ION/IOFF ratios (about 1E7), and reasonable sub threshold slope (about 0.3 V/decade). The threshold voltage (VT) however remains low (between -4 and -2 V) and needs to be improved.Finally, we have investigated the impact of a passivation layer on the performance of IGZO TFTs. SiO2 film (deposited by PECVD) and Al2O3 film (formed by ALD) were studied. We have observed that such passivation can degrade the TFTs rather than protecting them. Concretely, VT shifts in negative direction when increasing the Al2O3 layer thickness or the silane flow during SiO2 deposition. Principal reason for this shift is the presence of hydrogen which is generated during passivation. We have evaluated some solutions to reduce the degradation during deposition and ensure a good protection of the TFTs.
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Cu-catalyzed chemical vapour deposition of graphene : synthesis, characterization and growth kineticsWu, Xingyi January 2017 (has links)
Graphene is a two dimensional carbon material whose outstanding properties have been envisaged for a variety of applications. Cu-catalyzed chemical vapour deposition (Cu-CVD) is promising for large scale production of high quality monolayer graphene. But the existing Cu-CVD technology is not ready for industry-level production. It still needs to be improved on some aspects, three of which include synthesizing industrially useable graphene films under safe conditions, visualizing the domain boundaries of the continuous graphene, and understanding the kinetic features of the Cu-CVD process. This thesis presents the research aiming at these three objectives. By optimizing the Cu pre-treatments and the CVD process parameters, continuous graphene monolayers with the millimetre-scale domain sizes have been synthesized. The process safety has been ensured by delicately diluting the flammable gases. Through a novel optical microscope set up, the spatial distributions of the domains in the continuous Cu-CVD graphene films have been directly imaged and the domain boundaries visualised. This technique is non-destructive to the graphene and hence could help manage the domain boundaries of the large area graphene. By establishing the novel rate equations for graphene nucleation and growth, this study has revealed the essential kinetic characteristics of general Cu-CVD processes. For both the edge-attachment-controlled and the surface-diffusion-controlled growth, the rate equations for the time-evolutions of the domain size, the nucleation density, and the coverage are solved, interpreted, and used to explain various Cu-CVD experimental results. The continuous nucleation and inter-domain competitions prove to have non-trivial influences over the growth process. This work further examines the temperature-dependence of the graphene formation kinetics leading to a discovery of the internal correlations of the associated energy barriers. The complicated effects of temperature on the nucleation density are explored. The criteria for identifying the rate-limiting step is proposed. The model also elucidates the kinetics-dependent formation of the characteristic domain outlines. By accomplishing these three objectives, this research has brought the current Cu-CVD technology a large step forward towards practical implementation in the industry level and hence made high quality graphene closer to being commercially viable.
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Analysis and optimisation of window layers for thin film CDTE solar cellsBittau, Francesco January 2017 (has links)
The work presented in this thesis focuses on the investigation and improvement of the window stack of layers for thin film CdTe solar cells fabricated in the Center for Renewable Energy Systems Technology (CREST) laboratories. In particular the aim was to change the standard structure including TCO, high resistive transparent (HRT)layer and CdS which is limited by the low transparency of the CdS layer, to a better performing one. The first result chapter of the thesis describes the study of ZnO HRT layers. ZnO thin films were deposited by radio frequency (RF) magnetron sputtering with different structural, optical and electrical properties which were characterized by X-ray diffraction, electron microscopy, spectrophotometry, Hall Effect method and 4-point probe. ZnO films were then incorporated in CdTe solar cells with the structure: FTO/ZnO/CdS/CdTe/Au back contact and the performance of these devices were compared with the film properties to single out trends and identify optimal film characteristics. By varying the deposition pressure of ZnO films, it was possible to increase their transparency and significantly increase their resistivity. While better transparency positively affected the solar cell current density output and efficiency, the resistivity of ZnO films did not show any clear impact on device efficiency. By increasing the deposition temperature the ZnO film grain size was increased. Increased FF was observed in devices incorporating ZnO layers with bigger grains, although this gain was partially counterbalanced by the Voc degradation, leading to a limited efficiency improvement. Finally the addition of oxygen had the main effect of increasing the resistivity of ZnO films, similarly to what happened with the increase of the sputtering pressure. In this case however, an improvement of FF, Jsc and efficiency was observed, especially at an O2/Ar ratio of 1%. By simulating the solar cells behavior with SCAPS-1D, it was found that these performance change can be explained by the variation of interface properties, precisely the amount of interface defects, rather than by bulk properties. The study presented in the second result chapter focuses on magnesium-doped zinc oxide (MZO) and the variation of its energy band structure. MZO was initially used as the HRT layer within a solar cell structure: FTO/MZO/CdS/CdTe/Au back contact. Sputtering MZO films with a target containing MgO 11 weight% and ZnO 89 weight% allowed for and increased band gap from 3.3 eV of intrinsic ZnO to 3.65 eV for MZO deposited at room temperature. Increasing the superstrate deposition temperature allowed for a further band gap increase up to 3.95 eV at 400 °C due mainly to an conduction band minimum upward shift. It was highlighted the importance to create a positive conduction band offset with the MZO layer conduction band slightly above the CdS conduction band, with an optimum found in this case to be 0.3 eV (efficiency 10.6 %). By creating a positive conduction band offset all the performance parameters (Voc, FF, Jsc, efficiency) significantly increased. One of the reasons for this improvement was found to be a diminished interface recombination due to a more ideal MZO/CdS band alignment. In the second part of this investigation the MZO was used as a replacement for the CdS in a simplified structure: FTO/MZO/CdTe/Au back contact. The concepts used to optimise the performance of these devices also involved tuning the conduction band alignment between MZO/CdTe and efficiencies of 12.5 % were achieved with a at conduction band offset. The efficiency increase was achieved mainly thanks to a better transparency of the MZO layer and a higher Jsc output, compared to devices using a CdS buffer layer. The MZO buffers have been tested in combination with different TCOs. Results are presented in the third result chapter and showed that AZO is a good alternative to FTO working effectively in combination with MZO. AZO/MZO efficiency thin film CdTe solar cells (12.6%, compared to 12.5% with FTO). It was found that increasing the IR transparency of the TCOs leads to a potentially higher Jsc. Achieving a better transparency was obtained by using TCOs with high mobility and lower carrier concentration (AZO and ITiO) and also by using a boro-aluminosilicate glass with low iron content. ITiO yielded the best opto-electrical properties among all the TCO materials. Devices incorporating ITiO however, showed lower performance then those using FTO and AZO. ITO/MZO windows also yielded poor performance. In addition, the ITO films deposited had a high carrier concentration leading to a high NIR absorption by plasma resonance and resulted not ideal for application in thin film CdTe PV.
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Nouveaux nanomatériaux pour la fabrication d'électrodes flexibles transparentes / New nanomaterials for manufacturing flexible transparent electrodesCabos, Anthony 05 October 2017 (has links)
Les électrodes transparentes sont des éléments essentiels pour de nombreux dispositifs tels que les cellules solaires, les OLEDs, les écrans tactiles ou les films chauffants transparents. Au regard de la croissance forte du marché des dispositifs flexibles, le remplacement de l’ITO, matériau de référence dans l’industrie, s’avère nécessaire. Les réseaux percolants à base de nanofils(NF) métalliques sont une alternative de choix pour ce qui est des performances optoélectroniques, du coût et de la flexibilité. En particulier, les NF d’argent, fortement étudiés ces dernières années, offrent probablement le meilleur potentiel. L’objectif de cette thèse est de développer de nouvelles électrodes transparentes à NF avec un métal de substitution. Le cuivre est un candidat intéressant car à conductivité électrique équivalente, son prix est environ cent fois moins élevé que celui de l’argent. Dans ce manuscrit, différentes voies de synthèse des nanofils de cuivre (CuNF) sont abordées. Des électrodes sont fabriquées à partir de ces nanofils, notamment par impression, et des études sont rapportées sur l’évaluation de leurs performances. L’étude de la stabilité des électrodes à CuNF sous différents stress environnementaux (air sec, soleil, humidité) a été effectuée et met en évidence la stabilité moindre des NF de cuivre par rapport aux NF d’argent. Pour pallier cela, deux stratégies de protection des réseaux de nanofils ont été mises en place à base, soit d’une couche encapsulante sur le réseau, soit d’un système coeur-coquille à l’échelle du NF. La stabilité de ces systèmes a été mesurée lors du fonctionnement de ces électrodes lorsqu’elles sont utilisées pour la fabrication de films chauffants transparents. / Transparent electrodes are implanted in a lot of devices such as solar cell, OLED, touch screen or transparent film heater. Market trends toward flexible devices lead replacement of the well known brittle ITO. Metallic nanowire (NW) based percolative networks are a promising alternative in terms of performances, cost and flexibility. Indeed, the widely reported silver NWs exhibited really high optoelectrical performances. The objective of this thesis is to develop new NW based transparent electrodes with other metal. Among metals, copper is the most promising because of its high conductivity and its price one hundred times cheaper. In that manuscript, we detail different synthesis of copper nanowire (CuNW), their printing to get the related performances. Then ageing under environmental stresses (dry air, sun and humidity) will be studied. Stability of CuNW into networks is very low compared to silver, to improve stability of CuNW two strategies based on capping layer on top of CunW and on core-shell nanostructure will be presented. Operating stability into transparent film heater will also be reported.
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Fonte de potência para síntese de filmes finos por pulverização catódica na faixa de khz / Power supply for thin film synthesis by cathodic spraying in the khz bandRabelo, Wagner Henrique 28 May 2018 (has links)
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Previous issue date: 2018-05-28 / O avanço das técnicas de deposição de filmes finos sobre as superfícies dos materiais tem permitido agregar valor e dar novas funcionalidades aos produtos. Atualmente, os filmes finos de óxido de estanho dopado com índio (ITO) têm encontrado grande aplicação no mercado. Entretanto, devido à pouca disponibilidade do índio na natureza e aos altos custos envolvidos na sua aquisição, elementos alternativos estão sendo estudados para sua substituição. Nesse contexto, destaca-se o óxido de zinco dopado com alumínio (AZO) como um promissor substituto, devido às características de elevada transmissividade, baixa resistividade e band gap da ordem de 3,37 eV, que permitem sua aplicação na síntese de filmes finos semicondutores. Com base no exposto, neste trabalho, foi projetado e desenvolvido o protótipo de uma fonte amplificadora de potência (FAP) de corrente alternada (AC) em baixa frequência, operando entre 15 a 40 kHz, responsável por iniciar e sustentar o campo elétrico utilizado para a geração do plasma. Esta FAP foi utilizada para a deposição de filmes finos de (AZO) por meio da técnica de magnetron sputtering. A análise das características morfológicas, ópticas e elétricas dos filmes de AZO produzidos neste estudo resultaram em uma transmitância superior a 80%, energia de band gap de 3,82 eV, e resistividade de 1,46.10-3 .cm, permitindo concluir que o filme produzido se comporta como um TCO (óxido transparente condutivo). A comparação desses resultados com trabalhos disponíveis na literatura, permite concluir que a fonte amplificadora de potência desenvolvida nesta dissertação possibilita a obtenção de filmes finos de AZO com condutividade e transparência superiores àqueles produzidos com fontes operando em radiofrequência, técnica atualmente disponível e amplamente utilizada no mercado. / The development of thin films deposition techniques allows to increase value and give new features to the materials. Currently, indium doped zinc oxide (ITO) is widely used in the market. However, due to the low availability of the indium in the nature and the high costs involved on its acquisition, alternative elements are being studied for its replacement. Aluminum doped zinc oxide (AZO) stands out as a promising substitute, mainly because of its characteristics, such as high transmissivity, low resistivity and band gap value of 3.37 eV. That allow the application of AZO in the synthesis of thin films semiconductors. In this work, it was developed a prototype of a plasma power source amplifier (FAP) to operate in alternating current (AC) and low frequency (15 - 40 kHz), responsible for initiating and sustaining the electric field used for plasma generation. This FAP was used to deposit AZO thin films by the technique of magnetron sputtering. The analysis of the morphological, optical and electrical characteristics of the AZO films produced in this study resulted in more than 80% transmittance, band gap energy value of 3,82eV, and resistivity of 1,46.10-3 .cm. The thin films synthetized was classified as transparent conductive oxide (TCO). The comparison of these results with the characteristics of similar films avaiable in the bibliography, allows to conclude that the power amplifier source developed in this dissertation makes it possible to obtain thin films of AZO with conductivity and transparency superior to those produced with RF magnetron sputtering, technique currently available and widely used in the market.
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Influence de l'élasticité du substrat sur la genèse, propagation et coalescence des structures de cloquage de revêtements et films minces. / Influence of the elasticity of the substrate on the genesis, propagation and coalescence of coatings and thin films buckling structures.Boijoux, Romain 23 November 2017 (has links)
Le cloquage des films minces est un enjeu scientifique et industriel de premier plan, dans la mesure où il correspond au premier stade du délaminage a grande échelle du film, aboutissant généralement à la perte des propriétés fonctionnelles initialement conférées au matériau revêtu.L'influence de la souplesse du substrat sur ce phénomène est peu comprise à ce jour, alors que les systèmes industriels composés de films rigides sur substrats souples se multiplient. Cette étude se focalisera ainsi principalement sur l’influence de l’élasticité du substrat sur la genèse, propagation et coalescence des structures de cloquage, . L’approche expérimentale sera de générer des structures de cloquage élémentaires, de type ride droite, bulle ou « cordon de téléphone », et d’en contrôler la propagation, de manière à les faire interagir, se croiser, voire coalescer. La caractérisation morphologique de ces structures de cloquage se fera par microscopie à force atomique. Ces résultats expérimentaux seront confrontés à des simulations numériques par éléments finis réalisées en parallèle, permettant de tenir compte du couplage entre flambage du revêtement et délaminage de l’interface film/substrat. Les résultats obtenus permettront de mieux appréhender le phénomène de cloquage des revêtements et films minces. Cette étude répond ainsi principalement à trois questions : quelle est l’influence de l’élasticité du substrat sur la dynamique de propagation des cloques ? Comment se produisent leurs croisements aboutissant à des structures parfois singulières ? Cette élasticité favorise-t-elle la coalescence des cloques en cours de propagation, même si celles-ci ne se rencontreraient pas d’un point de vue purement balistique ?Enfin, l’intérêt technologique s’inscrit dans une démarche environnementale qui consiste à identifier les paramètres pertinents permettant d’inhiber le processus de cloquage, de le limiter, voire de le contrôler pour améliorer la durabilité des systèmes industriels. / Thin films buckling is a scientific and industrial challenge of primary importance, since it correspond to the first stage of the buckling of the film at a large scale, leading to the loss of the mechanical property initially conferred to the coated material.The influence of the substrate elasticity on this phenomenon is not well understood today, whereas the proportion of industrial systems made of rigid films on soft substrates increase. This study focus principally on the influence of the substrate elasticity on the genesis, propagation and coalescence of the buckled structures. The experimental approach consist in the controlled generation of elementary buckling structures, such as straight-sided buckles, blisters or “telephone cords” buckles, to make them interact and even meet and merge each other. The morphological characterization of such buckling structures will be performed by the atomic force microscopy technique. These experimental results will be then compared to finite elements simulations performed together, allowing to take into account the coupling between the buckling of the film and the film/substrate interface delamination. The obtained results will allow a better understanding of the coating and thin film buckling phenomenon. Thus, this study answer in particular to three questions : how the substrate elasticity impact the propagation dynamic of the buckles ? How their crossing occur, leading sometimes to complex structures ? Is this elasticity helps the coalescence of the buckles, even if they does not match each other in a “ballistic” way ?Finally, the technological goal is part of an environmental approach that consist in identifying the parameters that can suppress, limit or control the buckling phenomenon for specific applications.
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Une étude sur la fiabilité et le comportement thermomécanique de composant microélectronique type flip-chip / Study of reliability and thermomechanical behaviors of a flip-chip kind assemblyCellier, Ze 05 November 2013 (has links)
L’étude s’inscrit dans le cadre d’un projet Européen 3Dice, dont l’objectif est d’améliorer la fiabilité mécanique d’un composant microélectronique innovant. La miniaturisation du composant induit des difficultés lors de la caractérisation mécanique. Le développement de méthodes de caractérisation est nécessaire. La flexibilité du composant microélectronique est de plus en plus demandée. Les joints de connexion subissent souvent un pré-chargement. La tolérance du joint aux pré-chargements est intéressante à étudier. Cette thèse s’est déroulée autour de ces deux problématiques. Les méthodes de caractérisation de la couche mince métallique, la résine chargée en silice et le joint de connexion sont développées. L’étude de la fatigue du joint de connexion est effectuée. / This work is a part of an European fund project ‘3Dice’ which aims to improve the mechanical reliability of an innovated microelectronic product. The miniaturization of microelectronic component causes the difficulties to determine mechanical properties of materials involved. The development of experimental methods for microelectronic materials’ characterization is necessary. The flexibility of the products is an additional requirement recently in microelectronic field. The solder joint’s tolerance to the pre-load is interesting to investigate. The thesis is carried out based on these two topics. The characterization methods of thin film, resin with fillers and solder joint are developed. The fatigue behavior of solder joint is investigated under different displacement ratios.
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Étude expérimentale des écoulements film mince sur plan incliné avec contrecourant gaz dans des conditions de similitude aux écoulements cryogéniques / Experimental study of thin film flow an down inclined plane with counter-current air-flow similarto cryogenics flowsVitry, Youen 07 December 2011 (has links)
L’objectif est d’améliorer la connaissance des écoulements de films minces se développant au sein des colonnes servant à distiller les gaz de l’air sous conditions cryogéniques. Ce travail porte sur la caractérisation expérimentale de l’épaisseur du film liquide dans des conditions hydrodynamiques proches de celles rencontrées dans l’industrie. Tout d’abord, ce travail a permis de déterminer les conditions opératoires permettant la réalisation d’écoulement en similitude hydrodynamique avec les écoulements cryogéniques mais à température et pression proches de l’ambiant. Ensuite, un dispositif expérimental a ensuite été développé afin de permettre la réalisation d’écoulement de film liquide avec et sans contre-courant gaz sur plan incliné. Une métrologie optique utilisant un procédé de fluorescence a été développée et calibrée afin de mesurer des épaisseurs de films minces inférieures à 2 mm. Pour finir, l’étude expérimentale a permis de caractériser l’écoulement du film mince par l’étude statistique de son épaisseur, l’étude des régimes d’ondes de surface ainsi que son aire interfaciale. / The aim of this study is to get a better knowledge of thin film flow inside column used to distil the gases of air under cryogenic conditions. Experimental characterisation of the liquid film thickness submitted to hydrodynamic conditions similar to those found in real processes is investigated in this work. First, operating conditions were defined that allow thin film flow in hydrodynamic similitude with cryogenic flows but under conditions close to standard temperature and pression. Then, an experimental setup was designed in order to realize liquid film flows down an inclined plate with and without counter-current air flow. An optical technique using fluorescence was built and calibrated in order to measure the thickness of liquid film up to 2 mm. Finally, thin liquid film flow characteristics were experimentally studied with special attention given to the statistical variation of film thickness, interfacial wave patterns and interfacial area.
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