Дисертації з теми "Carbure de silcium - SiC"
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Abou, Hamad Valdemar. "Elaboration et caractérisation de contacts électriques à base de phases MAX sur SiC pour l'électronique haute température." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEI079.
Power applications in which the ambient temperature is high, cause the increase of temperature in electronic components. Therefore, it is important to develop electronic devices that are able to withstand high current and high-power densities. In this thesis, our objective is to lay the foundations of a new technology for the manufacture of a new generation of Ti3SiC2 MAX phase-based electrical contacts, stable, reliable and reproducible on Silicon Carbide for very high temperature applications (300 - 600ºC). To synthesize Ti3SiC2 on SiC, two elaboration methods were studied in this thesis. The first approach is a reaction method, and the second approach consists on using a Ti3SiC2 target via the Pulsed Laser Deposition (PLD) technique. Our goal is to develop a good quality ohmic contacts. Physico-chemical, electrical (TLM) and mechanical (W-H and RSM) characterizations were performed on the Ti3SiC2 contacts. These samples underwent a thermal aging test at 600°C for 1500 hours under Argon, in order to study the stability and reliability of the electrical contacts at high temperatures. The obtained results showed that the reliability and the chemical stability between Ti3SiC2 and SiC allowed the contacts to keep an ohmic behavior with low electrical resistivity, in addition to a good mechanical behavior, even after 1500 hours of aging at 600ºC. Furthermore, the thermomechanical simulations performed were used to determine the effects of Interfacial Thermal Resistances on the heat dissipation and the mechanical stresses exerted on a high power PN diode. In this thesis, we have shown that an ohmic contact, based on Ti3SiC2, can remain stable and reliable on a 4H-SiC substrate, in temperatures up to 600ºC
Boutry, Arthur. "Theoretical and experimental evaluation of the Integrated gate-commutated thyristor (IGCT) as a switch for Modular Multi Level Converters (MMC)." Thesis, Lyon, 2021. http://www.theses.fr/2021LYSEI095.
A study on Integrated gate-commutated thyristors (IGCT) di/dt limiting inductance and RCD-clamp reduction/suppression using plastic module silicon (Si) fast recovery diodes and silicon carbide (SiC) diodes, in Modular Multilevel Converters (MMC). This PhD contains:- Analysis of existing HVDC MMC Submodules.- Assessment of the interest of the IGCT in HVDC MMC Submodules and losses comparison with IGBTs, using MMC-specific figures-of-merit created in this thesis.- Double pulse test with fast recovery diode in plastic module to attempt to reduce and suppress the limiting di/dt inductor.- Packaging of High-Voltage High-Current SiC PiN diode dies, test with IGCT in the same setup to attempt to reduce and suppress the limiting di/dt inductor and analyze the specificities of the SiC diode in this setup
Song, Xi. "Activation des dopants implantés dans le carbure de silicium (3C-SiC et 4H-SiC)." Thesis, Tours, 2012. http://www.theses.fr/2012TOUR4019/document.
This work was dedicated to the activation of implanted dopants in 3C-SiC and 4H-SiC. The goal is to propose optimized process conditions for n-type implantation in 3C-SiC and for p-type in 4H-SiC.We have first studied the n-type implantation in 3C-SiC. To do so, N, P implantations, N&P co-implantation and the associated annealings were performed. The nitrogen implanted sample, annealed at 1400°C-30 min evidences a dopant activation rate close to 100% while maintaining a good crystal quality. Furthermore, the electrical properties of extended defects in 3C-SiC have been studied. Using the SSRM measurements, we have evidenced for the first time that these defects have a very high electrical activity and as a consequence on future devices.Then, we have realized a study on p-type doping by Al implantation in 4H-SiC with different implantation and annealing temperatures. Al implantation at 200°C followed by an annealing at 1850°C-30min lead to the best results in terms of physical and electrical properties
Balloud, Carole. "Méthodes de caractérisation optique de SiC." Montpellier 2, 2005. http://www.theses.fr/2005MON20193.
Berdoyes, Inès. "Interactions entre le silicium liquide et le carbure de silicium, application au composite SiC/SiC." Thesis, Bordeaux, 2018. http://www.theses.fr/2018BORD0113/document.
Increase of the air traffic and recent environmental standards require the reduction of the energy consumption and gas emission of the new aircraft engines. For this purpose, new materials have been developed.Lighter, chemically inert and suitable for high temperature applications, the Ceramic Matrix Composites SiC/SiC are promising materials for replacing some of the metallic turbine engine pieces and improving energy efficiency.From now on, CMC matrix was mainly elaborated by Ceramic Chemical Vapor Infiltration (CVI). However, this process is slow and costly, and the residual porosity is high. Then, the infiltration of liquid silicon (Melt Infiltration) in a SiC fibrous preform, coated with SiC (SiCCVI), and densified by SiC powders (SiCp) is an alternative route to full CVI.Even if liquid silicon (SiL) should fill the pores of the preform without reacting with SiC, local interactions have been noticed between the liquid silicon and the Sic deposit, which is deleterious to the final material mechanical properties. Therefore, this thesis aims at understanding the interactions SiL- SiCCVI and identifying the main parameters. This requires beforehand to characterize deeply and precisely the microstructure of the SiCCVI. Thereafter, research will focus on the control of the SiL- SiCCVI interactions
Ferro, Gabriel. "CROISSANCE EPITAXIALE DU CARBURE DESILICIUM A BASSE TEMPERATURE." Habilitation à diriger des recherches, Université Claude Bernard - Lyon I, 2006. http://tel.archives-ouvertes.fr/tel-00136241.
croître SiC en dessous de cette température tout en gardant une qualité de matériau (cristallinité et dopage) satisfaisante est un véritable défi dont les intérêts industriels sont évidents.
Cet objectif peut être atteint en utilisant des techniques en solution, sous gradient thermique
ou par mécanisme vapeur-liquide-solide (VLS). Différents bains et différentes configurations
de croissance ont été envisagés. Cette étude a permis de mieux cerner les difficultés de mise en oeuvre, de justifier les solutions techniques proposées et de sélectionner les alliages Al-Si comme meilleurs candidats. A partir de ces bains, l'homoépitaxie des polytypes hexagonaux (4H et 6H-SiC) a été démontrée pour des températures aussi basses que 1100°C. Les couches sont très fortement dopées p, par l'incorporation massive d'Al, de bonne qualité cristalline et assez rugueuses. Ce fort dopage p confère des propriétés électriques très intéressantes
notamment en terme d'abaissement de la résistivité de contact.
Le polytype cubique (ou 3C-SiC) ne disposant pas de substrats commerciaux de qualité suffisante, sa croissance a été réalisée par hétéroépitaxie sur substrat de Si(100) et a-SiC(0001) non désorientés, respectivement par EPV et VLS. L'EPV sur substrat de Si produit des couches de qualité cristalline médiocre en raison du fort désaccord de maille. La courbure
importante des plaques, résultant des contraintes thermiques, peut être diminuée en modifiant
l'étape de carburation. Un tel matériau pourra trouver des débouchés avec des composants peu
exigeants en qualité cristalline. Enfin, les alliages à base de Ge et Sn se sont montrés adaptés à
la germination du polytype 3C-SiC sur substrats hexagonaux. Des conditions de croissances
permettant d'éliminer les parois d'inversions dans les couches, ont été déterminées. Le matériau 3C ainsi épitaxié n'a pas d'équivalent ailleurs et est très prometteur pour développer un filière basée sur ce polytype.
Soueidan, Maher. "Croissance hétéroépitaxiale du SiC-3C sur substats SiC hexagonaux : analyses par faisceaux d'ions accélérés des impuretés incorporées." Lyon 1, 2006. http://tel.archives-ouvertes.fr/docs/00/13/62/31/PDF/these_soueidan.pdf.
Using silicon as substrate for growing 3C-SiC monocrystalline material generates too many defects in the layers due to lattice and thermal expansion mismatch. Though these difficulties are avoided by using hexagonal SiC substrates, the random formation of 60° rotated domains in the 3C layers generate a high density of twins. The use of vapour phase epitaxy for the growth did not allow reducing significantly the twin density despite the optimization of the in situ surface preparation of the seeds. On the other hand, these defects were eliminated by using Vapor-Liquid-Solid mechanism which consists in feeding a Si-Ge melt with propane. The characterization of these twin-free layers showed excellent crystalline quality. Some of the impurities incorporated during growth (Ge, Al, B, Sn) were successfully analysed using accelerated ion beam techniques though the detection and quantification of these elements inside SiC thin films are challenging
Nguyen, Le Minh. "Caractérisation mécanique de jonctions brasées SiC / BraSiC® / SiC et critère de dimensionnement à la rupture." Paris 6, 2011. http://www.theses.fr/2011PA066169.
Conchin, Frédéric. "Etude du comportement thermomécanique en relation avec la microstructure de matériaux à renfort fibreux SiC/C/SiC 2D." Lyon, INSA, 1994. http://www.theses.fr/1994ISAL0006.
The study of damage mechanisms and fracture behaviour of two ceramic-ceramic composite grades (2D SiC/C/SiC) is achieved by mechanical tests. These are conducted at room temperature (R. T. ), at high temperature (H. T. ) and at R. T. After ageing under different environments (vacuum, air and argon). The R curves are plotted under linear elastic behaviour assumption. At R. T. A fracture behaviour difference between two grades is exhibited : pro cess zone (large size) quasi static propagation with crack for the first one and edge effect (large bridging length) for the another one. At H. T. Degradation of the materials being observed and after ageing no significant variation is observed. The mechanical properties drops at H. T. Are due to the interface and interphase modifications and degradation fibres and to a lower extent to fibre degradation The study of R curves shows the difficulty to obtain intrinsic parameters m case of fibre composites (bridged crack). This is the reason for which a first approach based on bridging stresses crack opening dis placement relationship (μ-u curve) is proposed. The first results at R. T. And at H. T. Seem to confirm the theoretical analysis
Georges, Annick. "Oxydation sèche des réfractaires : Alumine, graphite, SiC." Nancy 1, 1986. http://www.theses.fr/1986NAN10352.
Ait-Mansour, Kamel. "Terminaisons de surface de SIC(0001) et leur influence sur la croissance de Ge." Mulhouse, 2004. http://www.theses.fr/2004MULH0768.
Blanc, Caroline. "Elaboration et caractérisation de composants type MOSFET en 4H-SiC orienté (11-20)." Montpellier 2, 2005. http://www.theses.fr/2005MON20220.
Vix-Guterl, Cathie. "Comportement en atmosphère oxydante de composites thermostructuraux SiC/C/SiC." Mulhouse, 1991. http://www.theses.fr/1991MULH0198.
Chourou, Karim. "Contribution à l'étude de la cristallogenèse du carbure de silicium SiC par sublimation." Grenoble INPG, 1998. http://www.theses.fr/1998INPG0087.
Ballestero, Anthony. "Elaboration de matériaux à base de carbure de silicium et à porosité contrôlée." Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT192/document.
Preceramic polymers have been proposed in the late fifty’s as non-oxide silicon based ceramic precursors generally called PDCs for “Polymer Derived Ceramics”. Compared to traditional synthesis ways, the PDCs route can offer many advantages in terms of compositions, structures and textures of ceramics. Due to its intrinsic properties (thermal, chemical and mechanical resistance, semi-conductor behavior,...), silicon carbide (SiC) and their derivatives with nitrogen (silicon carbonitride, SiCN) can be considered as one of the best materials for the next generation of ceramic based membranes, in particular in the hydrogen production processes (from CO2, CH4 or through the water gas shift reaction for example). By investigating the PDCs route, a hydrophobic and amorphous SiC material suitable for hydrogen separation process exhibiting good permeability/selectivity ratio, high thermal mechanical and chemical resistance coupled with a good stability under wet atmosphere up to 500°C can be proposed. However, the use of preceramic polymrers induces an important dimensional modification during the pyrolysis allowing the conversion from polymer to ceramic. Residual stresses caused by the volume shrinkage leads to the formation of cracks or even collapses of the structure of shaped preceramic polymers. This study is focused on the elaboration of SiC based macroporous substrates or microcellular foams, mesoporous and microporous coatings in the aim to propose a SiC based material showing a hierarchized porosity dedicated to gaseous separation applications. The AllylHydridoPolycarbosilane (AHPCS) is used as SiC precursor. After the chapters I and II, respectively dedicated to a literature review and the materials and methods used, two strategies are enforced in the chapters III and IV to generate these materials with a better control of the polymer dimensional change. In the first strategy (chapter III), passive (nanodiamonds) and active (boron particles) fillers are introduced in the AHPCS to generate some formulations with different fillers proportions and opposing to the volume shrinkage of the polymer during the pyrolysis and create composite materials. In the second strategy (chapter IV), a single molecular source approach consisting of the introduction of boron at the molecular state in the AHPCS is proposed. This introduction of boron leads to increase the ceramic yield and to reduce the mass loss of the modified AHPCS during the pyrolysis. In the chapters III and IV, monolithic dense structures are developed to better understand the dimensional change occurring during the pyrolysis. Synthetized and selected formulations and polymers will serve as precursors for macroporous, mesoporous and microporous materials in the chapter V
Gourbeyre, Christophe Barbier Daniel. "Caractérisation et modélisation de couches minces de 3C-SiC sur Si pour applications aux microsystèmes en environnements sévères." Villeurbanne : Doc'INSA, 2002. http://csidoc.insa-lyon.fr/these/2000/gourbeyre/index.html.
Gourbeyre, Christophe. "Caractérisation et modélisation de couches minces de 3C-SiC sur Si pour applications aux microsystèmes en environnements sévères." Lyon, INSA, 2000. http://theses.insa-lyon.fr/publication/2000ISAL0108/these.pdf.
Carried out within the framework of the development of the rnicro-technologies for harsh environment, this work is articulated around two principal axes. In a first part, a detailed study of the physical characteristics of layers of 3C-SiC deposited by CVD on silicon substrate is undertaken. The results extracted from this study relate in particular to the control of the residual stress present in the as deposited layers of 3C-SiC according to the conditions of epitaxy, in order to approach a quasi null stress. Moreover, the feasibility of self-suspended square membranes of 3C-SiC from 3 to 8 ~m thickness and 3 mm size side is proven. The study under Joad of such structures enabled us to extract the Young modulus from the various layers and to have access to the residual stresses present in the membranes of 3C-SiC. It also allowed us to better determine the origins of the disparity of the states of stress in the layers of SiC on full silicon plate. In a second part, we developed two models of structures by finite elements using the software Ansys 5. 4. , comprising a thin film of SiC. One models the thermo-elastic stress present in the layers of SiC on full silicon plate. By comparing this simple mode) with experimental results, it is possible to validate the choice of the physical parameters resulting from the literature, used for the FEM. The other models developed by FEM, is the one of a self-suspended square membrane of 3C-SiC which, compared with measurements under loads carried out on real structures, gives very convincing results when the residual stresses of the layers are purely thermo-elastic (to 5% near)
Gomina, Moussa. "Etude mecanique de materiaux a structure grossiere : comportement a la rupture de composites a fibres c-sic et sic-sic." Caen, 1987. http://www.theses.fr/1987CAEN2042.
Forbeaux, Isabelle. "Contribution à l'étude des propriétés électroniques des surfaces de 6H-SiC reconstruites et graphitées." Aix-Marseille 2, 1998. http://www.theses.fr/1998AIX22094.
Agullo, Jean-Marc. "Dépôt chimique en phase vapeur de SixC1-x riche en carbone : application au traitement d'interfaces fibres-matrice de matériaux composites SiC/SiC." Toulouse, INPT, 1991. http://www.theses.fr/1991INPT002G.
Othman, Dhouha. "Etude d'interrupteurs en carbure de silicium et potentiel d'utilisation dans des applications aéronautiques." Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLN033/document.
The potential of wide band gap transistors based on silicon carbide are remarkable and open new prospects for improvement (high efficiency, high breakdown voltage, high switching frequency and high operating temperature ...). This leads to volume and weight reduction for future converters. In order to improve new generation of power converters for future needs, Thales, in cooperation with SATIE and LTN IFSTTAR laboratories, performs investigations on the performances, advantages and disadvantages of SiC technology semiconductors. This comparative study will assess the strengths and weaknesses as well as the stresses induced during integration into aircraft converters of commercially available devices
Grateau, Luc. "Étude du comportement mécanique de composites monofilamentaires SiC/SiC : rôle de l'interface." Paris 11, 1987. http://www.theses.fr/1987PA112479.
The aim of this research was to study the mechanical behaviour of elementary ceramic composite materiels. Each composite is constituted of a SiC based Nicalon fibre coated with a ß-SiC "matrix" obtained by low-pressure chemical vapour deposition. The influence of a prior surface treatment of the fibres (deposition of a thin film of pyrolitic carbon) has also been investigated. A tension test has been developed for these systems to determine their mechanical characteristics stress-strain curves, load transfer, friction, modulus, damage assement. The SiC/ /SiC composites, which hace no carbon interphase, exhibit a brittle behaviour: a single crack initiates in the matrix and propagates through the fibre. The SiC/C/SiC composites which contains a carbon interphase exhibit a non-linear mechanical behaviour as in the case of unidirectional ceramic composites multiple fracture occurs in the matrix with deviation of cracks at the matrix/fibre interface. For these composites, the average friction stress at the interface could be determine from the measured extraction work. It could be shown, in some cases, that the friction stress is a fonction of the matrix volume fraction, indicating a fretting effect resulting from thermal residual stress. In several cases, "stick-slip" phenoma during the extraction of the fibre could be recorded. The approach developed in this work permits permits to characterize the dynamic behavior of these elementary composites and could be applied for example to test the effect of different surface treatments
Hida-El, Harrouni Ilham Guillot Gérard Bluet Jean-Marie. "Analyse des défauts et des propriétés électroniques du SiC-4H par voie optique." Villeurbanne : Doc'INSA, 2005. http://docinsa.insa-lyon.fr/these/pont.php?id=el_harrouni.
Hida-El, Harrouni Ilham. "Analyse des défauts et des propriétés électroniques du SiC-4H par voie optique." Lyon, INSA, 2004. http://theses.insa-lyon.fr/publication/2004ISAL0073/these.pdf.
The capability of silicon carbide (SiC) for application in high temperature, high power and high frequency electronics has been clearly evidenced by the realisation of numerous demonstrators. Nevertheless, the industrial development of such devices requires a drastic improvement of initial material quality. This is both a decreasing of crystallographic defects density and improvement in the homogeneity of full wafers electronic properties. This work takes part of this dynamic using non destructive optical characterization for the study of SiC wafers quality. Scanning photoluminescence (SPL) has been used for defects microscopic analysis. We have obtained the optical signature of deleterious defects (micropipes, dislocations, triangular defects) for SiC components. The gettering effect of non radiative traps by dislocations has been evidenced. Defetcs with triangular shape, commonly observed on homoepitaxy has also been investigated. Two different populations have been distinguished by SPL spectral measurements. The first one corresponds to cubic inclusions; the second one is stacking faults. Finally, an original technique for the cartography of carrier lifetime and doping has been developed. This is done using the theoretical relation and between the PL intensity and the excitation density. The good correlation between this approach and the lifetime measurements by PL decay validates the technique. SPL, together with other optical characterisations, is so a powerful tool for the determination of electronic parameters uniformity which control the devices properties, and, for a better understanding of crystalline defects impact on devices deficiencies
Fraga, Malfatti Célia de. "Elaboration et caractérisation de revêtements nanocomposites NiP/SiC électrodéposés." Toulouse 3, 2004. http://www.theses.fr/2004TOU30287.
In this work electrodeposited Ni-P/SiC composites coatings had been electrodeposited from a nickel salts solution containing H3PO3 and SiC particles in suspension (600nm and 30nm). Through measures of viscosity and sedimentation speed it was evidenced that the size of particles is a very important characteristic and it influences in the suspension stability. We had shown that organic additives modifies the characteristic of suspensions. Depending on size particles the organic additives can change the number of incorporated particles. It was observed that depending on the particles concentration in suspension, the number of incorporated particles in deposits can be changed. The incorporation rate evaluated as a function of the fraction in volume reaches a plateau, but continues to increase if it´s evaluated as a function of the number of particles. For the suspensions with raised particles concentration, the incorporation process becomes selective, and the particles with small size are preferentially incorporated. Microhardness measurements, thermal analysis and electrochemical analysis, (cyclic voltammetry and electrochemical impedance spectroscopy) were used to evaluate the influence of the amount and distribution of SiC incorporated particles on the microhardness, corrosion and thermal behaviour of Ni-P/SiC composite coating
Bechelany, Mikhael Miele Philippe Cornu David-Jacques. "Nouveau procédé de croissance de nanofils à base de SiC et de nanotubes de BN étude des propriétés physiques d'un nanofil individuel à base de SiC /." [s.l.] : [s.n.], 2006. http://tel.archives-ouvertes.fr/docs/00/13/94/30/PDF/These_Bechelany.pdf.
Bechelany, Mikhael. "Nouveau procédé de croissance de nanofils à base de SiC et de nanotubes de BN : étude des propriétés physiques d’un nanofil individuel à base de SiC." Lyon 1, 2006. http://tel.archives-ouvertes.fr/docs/00/13/94/30/PDF/These_Bechelany.pdf.
This study is focused on SiC nanowires (NWs) and BN Nanotubes (NTs). A new process, based on the high-temperature (1400°C) reaction of carbon precursors with silicon precursors on the surface a graphite plate, was found to yield mass-production of SiC NWs. The main advantages of this process are the low-cost of the ensuing NWs, no requirement of any purification step, and the possibility to generate in situ a coating on the NWs surface with tunable chemical composition (silica or carbon) and tunable thickness. Chemical and Structural modifications of these SiC NWs have been performed and yielded multifunctional 1D nanostructures, incorporating for instance BN and ZnO. The process was successfully extended to the synthesis of BN NTs. The latter have also been prepared by template route associated with the polymer-derived ceramics approach. Borazine, H3B3N3H3, was used as molecular precursor. Advances towards applications were performed with the localization of SiC NWs onto Si or SiC substrates, and the successful incorporation of SiC NWs into inorganic matrices. Physical properties of an individual SiC NW was studied by Raman Spectroscopy and Field Emission
Mouradoff, Luc. "Interaction de céramiques non-oxydes (Si3N4, SiC, AlN) avec l'aluminium liquide." Limoges, 1994. http://www.theses.fr/1994LIMO0033.
MOZDZIERZ, NATHALIE. "Relations entre le comportement a haute temperature et l'evolution microstructurale de materiaux ceramiques a base de carbure de silicium - sic monolithiques et composite sic/c/sic." Paris 11, 1994. http://www.theses.fr/1994PA112046.
Al-Azri, Maya. "Structural and magnetic properties of Mn implanted 6H-SiC." Paris 13, 2013. http://scbd-sto.univ-paris13.fr/secure/edgalilee_th_2013_al_azri.pdf.
Dans cette étude, des substrats 6H-SiC (0001) de type-n ont été implantés avec trois concentrations de Mn' : 5 x 10¹⁵ Mn/cm² (teneur en Mn : 0,7%), 1 x 10¹⁶ (~ 2%), et 5 x 10¹⁶ cm² (7 %) à une énergie d'implantation de 80 keV et pour une température de substrat de 365° C. Les échantillons ont été caractérisés par spectroscopie de rétrodiffusion de Rutherford, diffraction des rayons-X à haute résolution, spectroscopie micro-Raman et magnétométrie SQUID. L’objectif est d’étudier l’effet des défauts induits par l'implantation et de déduire une corrélation avec les propriétés magnétiques. Les résultats obtenus à partir des résultats de RBS/C montrent que 41% des Mn occupent les sites de substitution pour la plus faible concentration, 63% pour la concentration intermédiaire, alors qu’une structure amorphe apparaît pour la dose la plus élevée. Les cycles d'hystérésis présentent des formes typiques d’une réponse ferromagnétique. Le moment magnétique maximal a été obtenu pour la concentration 1×10¹⁶ Mn/cm² à laquelle le taux de Mn en site de substitution est maximal. Les résultats expérimentaux ont été confrontés aux résultats des calculs ab initio. Différentes configurations de sites Mn et types d'occupation ont été pris en compte. Les calculs ont montré qu'un atome de Mn substitué sur le site d’un atome de Si possède un moment magnétique supérieur à celui d’un atome Mn sur un site C. Un modèle est introduit pour expliquer la dépendance de la structure magnétique au type d'occupation des sites. Les propriétés magnétiques de paires d’atomes Mn couplés, type ferromagnétique (FM) et antiferromagnétique (AFM), avec et sans sites voisins vacants, ont également été explorées
Royet, Anne-Sophie. "Contribution à l'optimisation d'une technologie de composants hyperfréquences réalisés en carbure de silicium (SIC)." Grenoble INPG, 2000. http://www.theses.fr/2000INPG0158.
Terziyska, Penka. "Propriétés de transport de [alpha] - SiC : application aux composants électroniques." Montpellier 2, 2003. http://www.theses.fr/2003MON20059.
Masarotto, Lilian. "Etude d'épitaxies et de substrats SiC par imagerie de photoluminescence." Lyon, INSA, 2001. http://www.theses.fr/2001ISAL0053.
Silicon carbide (SiC) is a semiconductor material with a wide band gap energy (2. 9 eV for 6H-SiC, 3. 2 eV for 4H-SiC), an high electric breakdown field (4 MV/cm), , a twice saturated electron drift velocity better than silicon and a thermal conductivity comparable with cuivre. Because of some of its superior physical properties in comparison with Si or GaAs, silicon carbide is an appropriate semiconductor for the development of high temperature, high power and high frequency electronics. Nevertheless, in spite of tremendous progress in SiC bulk growth and epitaxy, the rise of high performance and high reliability devices is still limited by the material quality. In order to analyse defects in SiC, to understand their origin and their impact on devices performance, a non destructive, affordable and few time consuming characterization tool is then strongly needed. Toward this end, we have developed a scanning photoluminescence (SPL) apparatus, initially conceived for III-V compounds analysis. Indeed, SPL is a non-destructive and fast method for spatial profiling of impurities and defects in semiconductors. First, because of SiC luminescence low efficiency and necessity of excite the material with UV source, we worked to optimise the signal to noise ratio and eliminate parasite wavelengths from UV excitation. We then could use developed apparatus to demonstrate its interest for the microscopic SiC defects characterization. The possibility for micropipes revelation (even for non emergent micropipes) without using chemical etching has been evidenced. The gettering effect of non radiative traps around dislocations resulting in a denuded zone in the vicinity of the defect has also been demonstrated. This phenomenon, characterized by an exhaust of the photoluminescence intensity near the dislocation, can be used for the determination of dislocation density on epitaxial layers without using chemical etching. We finally calibrated equipment and could by simulation calculate lifetime carriers from PL intensity
Ragaru, Christian. "Étude par microscopie électronique en transmission de la transformation de phase bêta-SiC, >alpha-SiC par maclage." Nantes, 1997. http://www.theses.fr/1997NANT2118.
Coyaud, Martin. "Caractérisation Fonctionnelle de Composants en Carbure de Silicium." Phd thesis, Université Joseph Fourier (Grenoble), 2002. http://tel.archives-ouvertes.fr/tel-00477631.
Nakahata, medrado Andressa. "Conception Tridimensionnelle optimisée d'un convertisseur de traction ferroviaire à base de carbure de silicium (Sic)." Thesis, Université Grenoble Alpes, 2020. http://www.theses.fr/2020GRALT041.
The rail industry is focused on the benefits of using wide gap devices in traction applications. Within the framework of the European project “Shift2rail”, the potential advantages of the use of components based on silicon carbide (MOSFET SiC) in future converters are studied as well as the potential impacts on the design of power modules. Computer tools for multi-physical simulation have progressed considerably and today allow a real CAD chain, from mechanical design to complete electrical simulation, and highlighting the value of an approach resolutely oriented towards simulation and optimization. However, the desire now is to go further than simply validating a solution via simulation. The challenge is to carry out the design using a methodology based on optimization strategies using these tools. In fact, the three-dimensional layouts of the components to achieve the conversion structures have already highlighted certain structural defects such as problems of balancing the currents in dynamics during switching, which lead to having to oversize these components: these phenomena will be clearly amplified with l semiconductors as fast as SiC MOSFETs. In addition, the usual design rules from decades of experience may be ineffective or even counterproductive in the face of this technological breakthrough that constitutes the use of large gap semiconductors.The analysis of phenomena within a complex medium power converter (like those used in regional trains) is not easy given the number of components and the way they are assembled. In order to model all the connectors (DC bus bars, phase bus bars, connection bus bars) and components (filtering capacitors, semiconductors, decoupling capacitors) considering their impact when switching semiconductors, especially due to parasitic impedances, is essential when analyzing and optimizing a complex system. This thesis proposes a design methodology based on current technology (IGBT Si) of the traction system. The aim of this work is to have methods which will then make it easier to adapt to the new constraints imposed by much faster switching speeds. A detailed study of the switching cell is presented, in order to analyze how to optimally size the decoupling capacitor to be integrated as close as possible to the switching cell. From frequency and time analyzes, we will show how to improve the choice of this key component of the power circuit, often dimensioned empirically and using feedback.The dynamic balancing of currents during the parallelization of semiconductors is also addressed in this thesis. The origin of these imbalances is both due to the power interconnections, but also to the interactions between the power circuit and the control ("driver"). This study will lead us to implement an optimization to make the distribution of currents as balanced as possible by modifying the geometry of the gate and emitter circuits. However, the generic approach proposed would apply entirely to a wider integration where degrees of freedom would be left on the design of the power module, by integrating for example the decoupling capacities
Dutto, Mathieu. "Procédé micro-ondes pour l’élaboration de composites B4C-SiC par infiltration et réaction de silicium, en vue d’applications balistiques." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEM021/document.
Many studies have shown the feasibility of processing silicon-boron carbide composite by infiltration of molten silicon through a porous preform made of boron carbide (Reaction Bonding Process). Using this method, the obtained composite contains a large amount of boron carbide, which is the hardest and the most interesting phase for ballistic application. In our developed process, the maximum processing temperature is 1600°C, which is far below the usual high temperature stage/pressure conditions commonly used to sinter B4C by conventional method (respectively 2200°C and40MPa). The main goal of this thesis is to develop a novel reaction bonded process based on microwave heating. Microwaves heating has many interesting features, including fast heating process, selective heating mechanism (in case of heating multi-materials) and volumetric heating distribution. . To fulfill our goal, many technological issues need to be addressed (working in controlled atmosphere and under microwave field, high temperature ...). This thesis reports the development of this novel process, and materials made from it, exhibit similar properties compared to those made conventionally. However, some microstructural differences were observed in SiC resulting phases. This thesis has allowed to-find out the boron carbide composite piece fabrication conditions in microwave cavity (Argon/Hydrogen10%, slight overpressure: 14bars)-show that mechanical properties (hardness, Young’s modulus…) obtained are comparable to those measured on conventionally reaction bonded produced materials. -show that formed SiC has some microstructural peculiarities, between vacuum samples (for conventional) and ones obtained in hydrogenous argon (using microwave).-show that it is possible to produce larger size piece (66mm of diameter). These results are shown to be promising for ballistic applications, including the fabrication of bulletproof jacket and light armor
Zoulis, Georgios. "Structural and optical characterization of SiC." Thesis, Montpellier 2, 2011. http://www.theses.fr/2011MON20015/document.
The main topic of this thesis is the structural and optical characterization of SiC samples. The samples were divided in three groups: bulk, thick and thin epilayers. The bulk samples were grown with the CF-PVT technique and used a modified crystal holder geometry. The objective was to filter the defects to and create high purity and quality seeds of 3C-SiC. The thick epilayers were grown with the sublimation epitaxy technique, trying to demonstrate the creation of low impurity n and p type layers for device applications. Finally the thin epilayers were grown with the vapour-liquid-solid technique and doped with Ga impurities in an effort to create either heavily p-type doped samples and components for white LED applications. The samples were studied with low temperature photoluminescence, micro-Raman, SIMS and transmission electron microscopy. With the help of these techniques it was possible to determine the impurity concentration and identif y the n or p character of these samples. A qualitative analysis of the quality of the samples was done using both the observation of the structural defects and the information from the optical characterization techniques. We were able to acquire information about physical parameters of 3C-SiC like the binding energy of Ga and Al, the Al bound exciton fine structure and the Al-N and Ga-N donor acceptor pair fine structure. The appearance of a new structural defect called the fourfold twin was observed and presented
Carminati, Paul. "Composites SiC/SiC à interphase de type BN de compositions variables et réactivité optimisée." Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0248/document.
SiC/SiC composites with SiC-based fibres and SiC matrix are developed for aeronautic applications. In order to improve their life time in an oxidizing atmosphere at high temperature, the use of BN interphase is recommended, as far as liquid boron oxide can protect the material. However, this glassy material is known to be very sensitive to moisture because boron oxide volatilizes quickly under high temperature. The aims of this work are (i) to maximise the structural organization of BN deposited by CVD/CVI to improve its oxidation resistance and (ii) to assess the interest of elemental addition to boron nitride allowing thermodynamic retention for B2O3 under wet air. Relationships between gas phase composition, deposition rates, and microstructure have been established in this work. Unfortunately, if the oxidation resistance of BN perpendicular to its (002) crystal planes increases with its structural organization, it appears to be hardly improved along the (002) planes. Nevertheless, aluminium addition to BN has led to Al4B2O9 crystals generation, asAl2O3 reacts together with B2O3 under high temperature. These materials therefore appear tobe able to seal SiC matrix cracks. As a result, the global oxidation resistance under wet air of SiC/SiC composites with B(Al)N interphases can been significantly improved. Additional oxidation tests, especially under thermal cycling, are needed to definitively conclude about this point
Dang, Dinh Lam. "Caractérisation, analyse et modélisation du MOSFET de puissance en carbure de silicium." Thesis, Université de Lorraine, 2019. http://www.theses.fr/2019LORR0052/document.
Silicon carbide (SiC) has actively been emerged as the most viable candidate of the wide band gap (WBG) semiconductors to replace silicon (Si) in the near future. Due to its inherent properties, SiC enables the development of new generation semiconductor devices that offer great performance improvements, resulting in more efficient and compact designs in various power electronics applications. The 1.2 kV SiC MOSFETs, which are by far the most important devices in the SiC family, have been quickly used as the replacement of Si IGBTs in many applications due to their superior characteristics. However, at an early stage of development, SiC MOSFETs come with their own list of technical and economic issues which have somehow limited their widespread implementation for power electronics applications. The characterization and modeling, in particular on-state of the SiC MOSFET, have been investigated in this dissertation to develop insight of the unique characteristics along with the effects on the design of power converters. In such a way, the characterization test benches for high voltage power MOSFETs have been developed. The device is characterized using appropriate methods, which allows the junction temperature to remain constant during the measurement. The characteristics are then analyzed and compared to these of Si counterpart to provide further understanding of SiC MOSFETs. Subsequently, a novel compact model has been developed for circuit simulation, taking into account physical phenomena including interface traps, short-channel, intrinsic JFET and temperature effects. As a modified version of the Shichman Hodges, the model employs a few adjustment parameters, which are mostly derived from curve fitting of experimental data, using optimization tool software. The proposed model with fairly simple current equation thus is expedient to represent the DC behavior of power MOSFET for a wide range of operation conditions. In the end, the thermal characterization of SiC MOSFETs is examined. The on-resistance has been proposed as a temperature-sensitive electrical parameter (TSEP) to estimate the junction temperature. In the presence of the interface traps, the dedicated test benches have been developed for SiC MOSFET temperature measurement based on TSEP. 3D Finite element (FEM) simulation is performed to investigate thermal distribution inside the module. By comparing with the experiments, the electro-thermal model is validated with acceptable accuracy
Robert, Teddy. "Spectroscopie des fautes d'empilement dans 4H-SiC." Montpellier 2, 2009. http://www.theses.fr/2009MON20166.
Brenet, Philippe. "Etude du comportement mécanique, en relation avec la microstructure, d'un composite céramique-céramique SiC/MAS-L." Lyon, INSA, 1994. http://www.theses.fr/1994ISAL0124.
The present study concerns the mechanical behaviour of composite SiC/MAS-L 2D and is basically divided into three large stages. The first stage consists of continuous/monotonic tensile tests and thereby a non-linear as well as a non-elastic behaviour was observed for the present material. Fatigue characteristics were observed under a periodic mode of loading and a change in the material behaviour was observed. This finally led to either a stability in the material behaviour or to fracture at a given stress well-known as the 'fatigue limit'. In the second part the fracture behaviour was characterized with a new approach : p(2u) curves. The said graphics hence represent the crack opening-stress in function of its opening displacement and thus have a direct role to play in the mechanical and microstructural study, notably in measuring the resistance to crack-opening. Finally surface rupture studies reveal the importance of residual stresses a_s well as the prime role of the asperities in the interfaces on the interfacial shear stress (ISS). The value of ISS was observed to be in the order of 3 MPa. A comparative study between the pull-out length of tensile and fatigue specimens showed that the fatigue effect results in the diminution of ISS due to the abrasion of interfacial asperities
Morvan, Erwan. "Modélisation de l'implantation ionique dans α-SiC et application à la conception de composants de puissance". Lyon, INSA, 1999. http://www.theses.fr/1999ISAL0115.
Ion implantation is a fundamental technique for the fabrication of electronic devices in Silicon Carbide (SiC). This is the only technique allowing selective doping of this semiconductor because dopant incorporation by thermal diffusion requires very high temperatures which are not compatible with the other technological steps. Physical, electrical and optical properties of SiC can be modified by the use of ion implantation. The fluence and energy accuracies allow a good control of implanted impurity distribution. Virtually any kind of impurity profile can be obtained by the use of multiple implantations with varying fluences and energies. In order to better understand and to optimise the implantation process and as guidance to investigation, it is very useful to model the physical phenomena involved and to simulate the implanted ion trajectories. A global study on modeling and simulation of ion implantation has been carried out. From this study, an ion implantation simulator for SiC single-crystals has been developed (6H, 4H, 3C). This simulator is based on the Montecarlo method in the binary collision approximation. Tabulation-interpolation routines have been developed in order to increase the simulation speed. The simulator has been validated with experimental dopant profiles (SIMS). Afterwards, it has been used to investigate the multiple implants profiles, the. Channeling phenomenon, the lateral dispersion of ions, the defects generated by the implantation process and the stochiometric disturbances. By combining published experimental results and simulation results, optimal implantation conditions have been determiaed (beam angles, r1uences and energies of multiple implants) for the fabrication of the active areas of power devices (bipolar diodes emitter and MOSFET source/drain). High temperature annealing has to be performed in order to recrystallise the SiC wh. Ich has been damaged by the implantation process and in order to incorporate implanted do pants. Activation of Al implanted at high energy has been evaluated by capacitance-voltage measurements and activation of N has been measured by me TLM method. P•nn • (Al) bi-polar diodes and lateral MOSFETs (N) have been fabricated and characterised
Bouchetou, Marie-Laure. "Elasticité et endommagement à haute température de composites fibreux C-SiC." Limoges, 1996. http://www.theses.fr/1996LIMO0028.
Arnault, Véronique. "Relations entre microstructure et comportement mécanique des composites SiC-SiC : analyse du rôle de l'interface dans le processus de fissuration matricielle dans des matériaux multifilamentaires." Lyon, INSA, 1989. http://www.theses.fr/1989ISAL0098.
In order to establish relation between the micro structure and the mechanical behaviour of SiC/SiC composites, this research is based on a micro mechanical approach. The experimental study of the fibre-matrix interface mechanical behaviour, leads to a modelling of the interfacial shear strength. It controls fibre-matrix sliding and load transfer between the components near a matrix crack. This model describes friction conditions including poissn's effects caused by the indentation load. In sit, tensile tests under optical microscope, permit to identify the rupture phenomenon in unidirectional and budirectioanal woven composites. It is therefore possible to describe the kinetics of damage cumulation, consisting of multiple cracking in the matrix. The high temperature tensile test device under optical microscope, which is developed in this work is very useful for understanding the behaviour of these materials at their working temperature. The interpretation of the progressive cracking phenomena is based on a numerical simulation using concepts of fibre-matrix sliding by interfacial shear strength, and failure statistics
Szwedek, Olivier. "Amélioration du comportement à l’oxydation à très haute température des composites carbone/carbone par des revêtements alternés SiC/HfC." Thesis, Bordeaux 1, 2010. http://www.theses.fr/2010BOR14184/document.
Carbon/Carbon composites are widely used materials in many fields of application for their outstanding properties. Nevertheless, these materials have the drawback of oxidizing at very low temperatures. The aim of this work consisted in depositing by means of Chemical Vapour Deposition (CVD) coatings made of silicon carbide (SiC) and hafnium carbide (HfC) in order to protect the composite up to 2000°C in an oxidizing atmosphere. This way of manufacturing has allowed reaching dense and continuous coatings. First, a thermodynamic study of the Hf-Cl-C-H chemical system has permitted to study the influence of HfC deposition parameters and to report them into deposition diagrams. Then, after the study of experimental conditions in the metallic hafnium chlorination step and the examination of chemical compatibilities of the two carbides by Spark Plasma Sintering (SPS), a parametric study of the CVD of HfC has been carried out. This has enabled determination of optimal deposition conditions of HfC in order to manufacture an HfC/SiC multilayered protection. SiC experimental conditions were taken from the literature. Besides the materials made by CVD, another kind of material protection made of HfC powder coated with SiC and then sintered has been also studied. Finally, materials based on those two protection concepts have been oxidized at very high temperature. Results have enabled to validate the multilayered protection up to 2000°C and the HfC/SiC sintered powder up to 1500°C
Honstein, Gabriele. "Etude thermodynamique et par spectrométrie de masse du comportement de poudres de carbure de silicium (SiC) à haute température." Grenoble INPG, 2009. http://www.theses.fr/2009INPG0095.
Silicon carbide (SiC) is a well known material, but there are still several aspects in its manufacturing which are not well known. The aim of this thesis is to contribute to better understanding of material flows exchange via gaseous phase during bulk SiC manufacturing. The characterization of established gaseous phase above SiC containing powder samples is performed in-situ using mass spectrometry with (i) Knudsen cell or (ii) capillary tubing sampling. The heat treated powders are then characterized using SEM imaging and Raman spectrometry to analyse their state of aggregation, especially necks building between single SiC grains. The experimental study is preceded by a thermodynamic study of the SiC-SiO2 system and SiC passive-active oxidation transition limits computations. The influence of main parameters like oxygen pollution and heating rate on the SiO(g) and CO(g) partial pressures was observed and relied to observed structure of obtained samples
Ariyawong, Kanaparin. "Modélisation des procédes de croissance de SiC en phase gazeuse (PVT) et en phase liquide (TSSG)." Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAI030/document.
Silicon Carbide (SiC) is one of the most desirable materials for power electronic devices. The development of the growth process, to achieve larger size and higher quality is on the way. Even if modeling has proved its ability to assist the optimization of the growth processes, there are still some strong issues which are not considered in a satisfactory way. This thesis aims to use the modeling tools to tackle those challenging fundamental and technological issues on both industrially used PVT and emerging TSSG processes. In the PVT process, special attention is paid to the physical chemistry at the solid-vapor interfaces. Especially, we investigated the way to model the stoichiometric crystallization of SiC from a non-congruent vapor as the Hertz-Knudsen model was shown to be not adapted. We thus considered SiC as a solid solution using coupled mass transport modeling and thermodynamics. This approach gives an assessment to the chemistry of the SiC crystal which can be linked to the controllable parameters. Such correlations may serve as a basis to control the points defect density, stable polytypes, and doping concentration. Concerning the TSSG process, the effects of crystal rotation speed and operating frequency are studied. The electromagnetic convection is the main contribution governing the growth process using low frequency while the combined buoyancy and Marangoni convections become dominant at high frequency. In the experimental conditions using low frequency, the crystal growth rate could still be enhanced by increasing the rotation speed. The phase parameter is also introduced using the combined fluid dynamics and analytical modeling. This provides a comprehensive visualization of the interactions between fluid flow and step flow and a guideline to improve the surface morphology of the crystal
Balestrat, Maxime. "Elaboration et caractérisation d'objets massifs nanocomposites base carbure de silicium comme absorbeurs solaires." Thesis, Limoges, 2019. http://www.theses.fr/2019LIMO0102.
A common industrial challenge to improve the efficiency of the solar-to-electricity conversion for concentrating solar power (CSP) is to operate at high temperatures (around 1000°C). Research and development efforts on over recent years have therefore focused on the materials that compose the solar absorber which plays the key role in the overall CSP system performance. Silicon carbide (SiC) exhibits a chemical inertness, a high temperature oxidation resistance and a robustness compatible with the operating conditions of further CSP systems. In this work, Polymer derived nanocomposites ceramics TiCxN(1-x)/Si(B)C et TiCxN(1-x)/SiC(N) (with 0<1) have been developed to be use as solar absorber. A complete characterization from the polymer to the final material is done using techniques as Solid-state NMR, FTIR, TGA, XRD, Raman SEM and TEM. The bulk shaping process was also investigated. Hot pressing at the polymeric state and Flash Sintering on amorphous PDCs powders has been done
Silly, Mathieu. "Etude des surfaces, interfaces et nanostructures du β-SiC(001) : propriétés électroniques, structurales et optiques". Paris 11, 2004. http://www.theses.fr/2004PA112306.
We study clean, silver covered, hydrogenated and oxidized β-SiC(001) by scanning tunnelling microscopy (STM), STM induced light, photoelectron spectroscopy using synchrotron radiation and grazing incidence X-ray diffraction (GIXRD). We determine the atomic structure of the silicon terminated β-SiC(001)-(5x2) reconstructed surface and deduce the structure of the Si atomic line. The various β-SiC(001) reconstructed surfaces are probed by STM induced light and exhibit different behaviour. The Si-rich (3x2) and C-terminated c(2x2) surfaces are destroyed by the tunnelling conditions (high current and high voltage), while the c(4x2) remains stable. We obtained topographic and photon atom-resolved images simultaneously in topography and photon emission for the (3x2), c(4x2) and silicon atomic lines. The contrasts in photon emission are interpreted as surface state variations. The atomic resolution in photon emission is also obtained with β-SiC(001)-(2x3)/Ag. We show that the silver covered Si atomic line presents differential negative resistance. For thick silver coverage on c(4x2), silver is organized in clusters, here the contrasts in photon emission are interpreted as localised plasmons variations. We show by photoelectron spectroscopy that pre oxidized (3x2) surface can be metallized upon atomic hydrogen exposure. Finally, the C-terminated surfaces are found to be much less reactive than Si-terminated surfaces towards oxygen