Dissertationen zum Thema „Phases porteuses“
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Priadi, Cindy Rianti. „Caractérisation des phases porteuses : métaux particulaires en Seine“. Paris 11, 2010. http://www.theses.fr/2010PA112288.
Der volle Inhalt der QuelleLn freshwater systems, metals are known to have a particular affinity for the solid fraction. Consequently, the latter may constitute a potential toxic risk for aquatic organisms. Sustainable management in the Seine River Basin requires characterizing particulate carrier phase of metals in order to determine its geochemistry, identify urbanization impact of the Greater Paris Region and deduce the sources of metals and their mobility. To achieve these objectives, suspended particulate matter (SPM) was studied in relative to the water column and zoomed upon until the metal's molecular environment. Ln agreement to previous studies, lead (Pb) was associated mostly to the solid fraction while nickel (Ni) was found mostly in the dissolved phase. As for the rest of the metals such as cobalt (Co), chrome (Cr), copper (Cu), manganese (Mn) and zinc (Zn), there seems to be a shared preference for the solid and dissolved phase. Downstream Paris, not only did solid lsolution partitioning of Co, Cu and Ni decrease, but also temporal variation of the partitioning during monthly observations, indicating more stable forms of carrier phases. As for cadmium (Cd), Pb and Zn, it was their oxidizable fraction in the SPM that increased downstream, particularly associated with iron oxides (FexOy). An identified source of these oxides would be the bed sediment. Ln the case of intense storm episode, the combined wastewater system would overload and a large volume of direct wastewater would overflow to the Seine River. Calculation using a mixing model suggested that bed sediment contributed from 30-50% of particulate metal found in the overflow plume. This is a relatively high contribution compared to the 10-30% of particulate metal which would originate from the overflow itself. Besides iron oxides, reduced environment in bed sediment and CSO would also contribute to ZnS found in the water column. These ZnS are identified as single or clustered amorphous nanoparticles. This species is rather stable as they are found to persist in oxic environment
Poitevin, Antonine. „Caractérisation multi-échelles des phases porteuses des polluants métalliques Zn et Pb dans un sédiment mis en dépôt : de l'analyse de terrain au rayonnement synchrotron“. Phd thesis, Université d'Orléans, 2012. http://tel.archives-ouvertes.fr/tel-00840257.
Der volle Inhalt der QuelleBossy, Angélique. „Origines de l’arsenic dans les eaux, sols et sédiments du district aurifère de St-Yrieix-la-Perche (Limousin, France) : contribution du lessivage des phases porteuses d’arsenic“. Limoges, 2010. https://aurore.unilim.fr/theses/nxfile/default/2e95ffd2-92b0-4376-aa7a-9206705f56ed/blobholder:0/2010LIMO4036.pdf.
Der volle Inhalt der QuelleIn order to understand the pollution of waters in arsenic (As), it is important to know the biogeochemical processes involved in the transfer of this metalloid from the solid reservoir to waters. The aims were to evaluate (i) the contribution of As-rich solid phases weathering, from natural geochemical anomaly, through mineralogical characterization and (ii) the abiotic and biotic mobilization of As during hydrological monitoring and laboratory experiments. The soil profile showed a decrease of As bulk content during pedogenesis. Mineralogical characterization of the As-bearing phases showed an evolution in the soil profile from arsenates (Ba-rich pharmacosiderite) in the bedrock and the 135-165 cm soil horizon into Fe-oxyhydroxides (goethite, hematite and ferrihydrite) less and less rich in As towards the soil surface. The monitoring of dissolved As in the aqueous compartment showed the contribution of ground-, wetland and mine waters, runoff and soil solutions (in the surface horizons) to surface water pollution. Indeed, in situ monitoring of dissolved As in soil solutions showed a higher As release in the 0-5 cm soil horizon (25-119 μg. L-1) than in the deep soil horizons (6-56 μg. L-1), suggesting that As-bearing phases were less and less stable during pedogenesis. In addition to the physico-chemical mobilization, this study showed the influence of bacterial activity on As speciation in the waters of watershed, with the dissolved As(III) release before the Fe(II) in the groundwaters
Ilunga, Ngoy Serge. „Impact des termites sur les cycles biogéochimiques du cuivre et du cobalt dans le Katanga (RDC) - Application à la prospection minière“. Electronic Thesis or Diss., Université de Lorraine, 2022. https://docnum.univ-lorraine.fr/ulprive/DDOC_T_2022_0207_ILUNGA_NGOY.pdf.
Der volle Inhalt der QuelleKnowledge of the influence of termites on transport of metals of economic interest within the complex of lithosphere, pedosphere and termite mounds is of great interest for geochemical and geological characterization of anomalies in mining prospection. Termites have an important functional role in the structuring of soils, causing chemical enrichment through the vertical transport of minerals exchanged between the deeper horizons and the termite mounds built at the surface. Our objective in this thesis is to evaluate the influence of termites on Cu and Co biogeochemical cycles in a mineral-rich region (Katanga, DRC), with the aim to optimize the utilization of termite mounds in mining prospection. This objective requires a characterization of mineral and organic phases at various scales. To achieve this, firstly, a geochemical mapping of termite mounds of two dominant genera of the region, Macrotermes and Cubitermes, was carried out at the landscape scale in an area that received a geological and soil and rock geochemical mapping. The utilization of termite mounds allowed the identification of lithogeochemical facies reflecting the subjacent geology on a regional scale according to the feeding habits of each termite genus. The spatial distribution of termite mounds also allowed us to follow Cu and Co content evolution according to study area geology. The combination of mineralogical and geochemical data acquired on Macrotermes falciger termite mounds and morphological and chemical characterization of their main constituents at microscopic scale allowed to identify carrier phases of interest metals in termite mounds materials. Similarly, the comparison of geochemical signatures of M. falciger termite mounds and their parent materials allowed to establish a lithogeochemical relationship, identifying the source of provisioning at depth by M. falciger. Finally, the association of geochemical characterization results of termite mounds for four granulometric fractions (0-20 µm; 20-63 µm; 63-200 µm; 200-2000 µm) and results on evaluation of the impact of termites on the constitution of aggregates in termite mounds and/or soils, allowed to specify the most informative granulometric fractions on the presence and mineralization of carrier phases of interest metals in Katanga in termite mound materials. The application of all these methods and all elements collected allowed us to propose a Cu and Co biogeochemical cycle scheme in this system, underlying the use of termite mounds in effective and efficient mining prospection
Deredempt, Olivier. „Étude comparative des algorithmes de recherche des phases de la porteuse et de l'horloge de bits d'un signal à modulation de phase“. Toulouse, INPT, 1993. http://www.theses.fr/1993INPT150H.
Der volle Inhalt der QuelleHallal, Ayman. „Génération d'ondes millimétriques et submillimétriques sur des systèmes fibrés à porteuses optiques stabilisées“. Thesis, Rennes 1, 2017. http://www.theses.fr/2017REN1S005/document.
Der volle Inhalt der QuelleI report in this manuscript a theoretical and experimental study of a compact, reliable and low cost source of 30 Hz linewidth, continuous and coherent electromagnetic waves tunable from 1 GHz to 500 GHz in steps of 1 GHz. These waves are generated by photomixing two distributed feedback (DFB) laser diodes at 1550 nm which are frequency stabilized with orthogonal polarizations on the same optical fibered Fabry-Perot cavity. I have designed very fast electronic control filters for each laser allowing a 7 MHz servo bandwidth limited by the loop length. I demonstrate phase noise suppressions down to -60 dBc/Hz at 1 kHz and -90 dBc/Hz at 100 kHz offset frequencies from a 92 GHz electrical carrier. I also measure a ~170 kHz frequency drift of the beat note at 10 GHz on the long term over a continuous 7.5 hour locking period. I show an optimized design of an integrated servo loop of few tens of cm length which reduces the phase noise by 18 dB at 1 MHz optical carrier offset frequency and the phase-amplitude couplings in the cavity by a factor of 50 compared to the experimental one. The addition of a third DFB laser phase stabilized on a local oscillator allows the possibility to have continuously tunable source over 1 THz. The continuous wave source also makes it possible to generate fixed repetition rate pico- or femtosecond pulses from highly non-linear and dispersive fibers, replacing the DFB lasers by further stable lasers. I have calculated by simulation 7.2 fs temporal jitter at 40 GHz repetition rate over a 1 ms integration time
Labidi, Tarek. „Amplification sensible à la phase de signaux analogiques sur porteuse optique“. Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS340/document.
Der volle Inhalt der QuelleMicrowave photonic links are expected to play an important role in future RF systems. Based on low loss optical fibers, analog photonic links (APLs) have become the heart of the emerging field of microwave photonics, in which various functionalities are explored such as the generation and distribution of radar signals and local oscillators, phase shifting, reconfigurable true time delays, or even more complex functions such as spectrum analysis or correlation of RF signals. Unavoidably, microwave photonics systems undergo losses due either to microwave-to-optical conversion or to propagation. Classical amplifiers based on erbium doped fibers, semiconductor amplification, or Raman scattering in fibers, do not allow to compensate for these losses without degrading the signal-to-noise ratio. The aim of this thesis is to address this issue and to theoretically study and experimentally an optical phase-sensitive amplifier based on highly nonlinear fiber (HNLF) in order to amplify an analog signals without adding noise. We experimentally investigate the linearity of a phase sensitive amplifier based on nonlinear optical fiber in the context of microwave photonics. The linearity of the PSA amplifier is assessed by performing third order intermodulation distortion products (IMD3) measurements using two RF tones. The results show that the PSA is, in the explored domain, perfectly linear for the RF modulation, leading to amplification without any increase of distortion, thus proving the compatibility with future microwave photonics applications. In addition, we study the performance of our PSA in terms of noise by taking measurements of the noise figure (NF). Indeed, we measure a noise factor of -2.07 dB in the case where when we detect only the signal, while a 0.2 dB noise factor is obtained when both "signal and idler" are detected
Aksas, Madjid. „Égaliseur aveugle linéaire avec recouvrement simultané de la phase de la porteuse /“. Montréal : École de technologie supérieure, 2003. http://wwwlib.umi.com/cr/etsmtl/fullcit?pMQ80816.
Der volle Inhalt der Quelle"Mémoire présenté à l'École de technologie supérieure comme exigence partielle à l'obtention de la maîtrise en génie électrique". Bibliogr.: f. [90]-92. Également disponible en version électronique.
Aksas, Madjid. „Égaliseur aveugle linéaire avec recouvrement simultané de la phase de la porteuse“. Mémoire, École de technologie supérieure, 2003. http://espace.etsmtl.ca/736/1/AKSAS_Madjid.pdf.
Der volle Inhalt der QuelleCliment, Éric. „Dispersion de bulles et modification du mouvement de la phase porteuse dans des écoulements tourbillonnaires“. Toulouse, INPT, 1996. http://www.theses.fr/1996INPT114H.
Der volle Inhalt der QuelleDervin, Mathieu. „Synchronisation de porteuse à très faible rapport signal à bruit pour applications satellite large bande“. Phd thesis, Télécom ParisTech, 2005. http://pastel.archives-ouvertes.fr/pastel-00001545.
Der volle Inhalt der QuelleVervisch-Picois, Alexandre. „Etude de systèmes de positionnement en intérieur utilisant des mesures de phase du code ou de phase de la porteuse de signaux de navigation par satellites“. Phd thesis, Institut National des Télécommunications, 2010. http://tel.archives-ouvertes.fr/tel-00626177.
Der volle Inhalt der QuelleVervisch-Picois, Alexandre. „Etude de systèmes de positionnement en intérieur utilisant des mesures de phase du code ou de phase de la porteuse de signaux de navigation par satellites“. Electronic Thesis or Diss., Evry, Institut national des télécommunications, 2010. http://www.theses.fr/2010TELE0012.
Der volle Inhalt der QuelleThe thesis proposes the study of systems of local constellations for positioning indoors.In this context, it appears that indirect paths disturb the measurement of time delay between the transmitter antenna and receiver antenna. The Near-Far problem between signals, a CDMA interference phenomenon, is exacerbated because of the short distances and variations in received power. The thesis provides answers to these two issues.For indirect multipath we propose to use carrier phase measurements. It must then solve the problem of ambiguity on these measurements. A method without carrying out a differential technique is proposed: a tracking loop insensitive to indirect routes: the SMICL. For the Near-Far problem, we have developed three approaches. One approach uses sequences of maximum length and significantly reduces its influence. A second method, called the Double Transmission Technique (DTT), can completely remove the interference for a pair of transmitters when their respective Doppler are equal. We have studied the case where different Doppler and developed an improved version of the DTT, the DTT extended to the carrier, which eliminates the influence of the Doppler. We also showed that this may also be applied to a fixed transmitter in the presence of a constellation of satellites. A third method, called DTT maximum, again uses a maximum length sequence to extend the method to the case DTT in the presence of several transmitters
Khaleghi, Hamidreza. „Influence des amplificateurs optiques à semi-conducteurs (SOA) sur la transmission cohérente de signaux optiques à format de modulation multi-porteuses (CO-OFDM)“. Phd thesis, Université de Bretagne occidentale - Brest, 2012. http://tel.archives-ouvertes.fr/tel-00829663.
Der volle Inhalt der QuelleSousa, Fernando Rangel de. „Application du corrélateur " Five-Port " aux PLLs, à la récupération de porteuse et à un MODEM de télécommunications dans la bande 1,8 - 5,5 Ghz“. Paris, ENST, 2004. https://pastel.archives-ouvertes.fr/pastel-00000987.
Der volle Inhalt der QuelleThe five-port correlator accurately computes the complex ratio between two radiofrequency signals from the power values measured at the output of a five-port interferometer circuit. Its application has been reported in radars, DOA systems, direct conversion receivers and, as we propose in this work, in PLLs and carrier recovery loops. Whereas classic cartesian correlators project a vector representing a modulated signal over an orthogonal basis, the five-port correlator performs this projection over a \textsl{basis} composed of three vectors ideally phase-shifted of 120°. Thanks to the redundancy added by the third vector, the five-port correlator is less sensible to phase and amplitude imbalances, allows for the estimation of the IM2 products and operates in a wider frequency band. This PhD research contributes to the mobile radiocommunication area, in particular to the multi-mode and multi-band transceivers. The first contribution is the application of the five-port technique to reconfigurable phase-locked loops. Secondly, these reconfigurable loops are exploited in a multi-mode carrier recovery loop. Then, we present an original five-port characterization method. Finally, we propose and evaluate a novel transceiver architecture based on a three-vector basis
Mannah, Marc-Anthony. „Transmission de données par courants porteurs en ligne sur un réseau modulé en largeur d'impulsion“. Nantes, 2010. http://www.theses.fr/2010NANT2034.
Der volle Inhalt der QuelleThis thesis studies the use of the Power Line Communication PLC technology in a motor inverter association for purposes of controlling and monitoring. This technology is widely used in domestic applications and allows a reliable communication through the sinusoidal electrical network. In a motor drive application, the electrical network is a Pulse Width Modulation network and consequently this technology may not work. Following a thorough study of the PWM signal, a series of experimental measurements using the domestic PLC modems over the PWM network were carried out and have underlined the inefficiency of the sinusoidal PLC technology. Based on the obtained results and on the PWM network requirements, we have developed industrial PLC couplers. The good functioning of these couplers has been validated in the frequency band 55 MHz – 85 MHz. A study of the required throughput in motor drive applications led us to define the QPSK modulation for data transmission. The modem was developed and communication was tested under different conditions with a throughput equal to 1. 6 Mbits/s. The different experimental measurements have demonstrated the PLC communication feasibility over the PWM network
N'Kaye, Eliane Christine. „Contribution à l'étude d'un modem numérique en phase différentielle D. P. S. K“. Paris 11, 1989. http://www.theses.fr/1989PA112411.
Der volle Inhalt der QuelleRoussignol, Philippe. „Nonlinéarités optiques de microcristaux de semiconducteur CdSSe en matrice de verre : dynamique des porteurs photoexcités et confinement quantique“. Paris 11, 1989. http://www.theses.fr/1989PA112212.
Der volle Inhalt der QuelleKanj, Amale. „Etude et développement de la méthode TWSTFT phase pour des comparaisons hautes performances d'étalons primaires de fréquence“. Phd thesis, Université Pierre et Marie Curie - Paris VI, 2012. http://tel.archives-ouvertes.fr/tel-00831596.
Der volle Inhalt der QuelleMohammedi, Merah Mounir. „Conception et réalisation d’un lien Light-Fidelity multi-utilisateur en intérieur“. Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLV061/document.
Der volle Inhalt der QuelleNowadays, the number of connected devices requiring access to mobile data is considerably increasing. The arrival of even more connected multimedia objects and the growing demand for more information per device highlighted the limits of the fourth generation of broadband cellular networks (4G). This pushed for the development of new methods, one of which is 5G. The goal is to be able to support the growth of wearable, sensors, or related internet-of-object (IoT) systems. The vision behind 5G is to enable a fully mobile and connected society with a consistent experience. In consequence, there is a fundamental need to achieve a seamless and consistent user experience across time and space.Small cells are the basis of advanced communications standards such as 4G and now, 5G. They exist as a result of using higher frequency bands for RF access in order to support new standards and the increasing demands in bandwidth. 5G use millimeter waves and requires a deployment across indoor and dense urban environment which may prove to be a challenge. This is where 5G will need to include hybrid networking solutions and be able to coexist with other wireless access technologies. Visible light communication (VLC) fits into that mold since visible light corresponds to the band between 400 and 800 THz. The available spectrum is multiple thousand times the size of the RF spectrum and it does not interfere with it. The technique combines illumination with communication at possibly tens of gigabits per second. It has the potential to offer a synergistic pairing with 5G in a hybrid network, offering high speed, no interferences, and more security at the cost of limited coverage and low technological maturity.The goal of this thesis is thus to propose and evaluate an experimental implementation of an indoor multi-user VLC system in order to answer the objectives of Li-Fi setup in the context of a small cell. The first step of this study is a detailed state-of-the-art on VLC in indoor wireless communication and multi-user access. It allows the design of our work to be better explained and to compare our approach with existing works. The second step is an analysis of the principles and hypothesis supporting the indoor multi-user VLC system in the study both on the modulation technique and the multi-user access schemes. The conclusions drawn from theoretical and numerical analysis are used as a basis for the rest of the work. The third step is the experimental setup investigations on the single-user broadcast performances optimization and then on the multi-user performances of the system using various schemes. The total throughput using an off-the-shelf white LED reaches 163 Mb/s with a bit-error rate decreased by a factor of 3.55 thanks to the performance optimization process. This technique has the advantage of increasing the flexibility for a multi-access scenario while not augmenting the complexity as it only optimizes the modulation filter parameters. The multi-user access is obtained for a cell size of 4.56 m² at a distance of 2.15 meter away from the transmitter. The user capacity can reach up to 40 users, or 40.62 Mb/s in a 4-user scenario. It is thus demonstrated that the proposed system could function as a cell at a realistic range, with high data rate and the ability to provide for a large amount of users while limiting the cost of implementation
Bestory, Corinne. „Développement de stratégies de conception en vue de la fiabilité pour la simulation et la prévision des durées de vie de circuits intégrés dès la phase de conception“. Thesis, Bordeaux 1, 2008. http://www.theses.fr/2008BOR13627/document.
Der volle Inhalt der QuelleDesign for reliability (DFR) consists in assessing the impact of electrical ageing of each elementary component, using electrical simulations, on performance degradations of a full device. According to DFR concept and reliability simulation, theses works present a new DFR strategy. This strategy based on the integration of two intermediate phases in the ICs and SoC design flow. The first phase is a bottom-up ageing behavioural modelling phase of a circuit (from transistor level to circuit level). The second phase is a « top-down reliability analyses » phase of this circuit, performing electrical simulations using its ageing behavioural models, in order to determine critical functional blocks and / or elementary components of its architecture according to a failure mechanism and a given mission profile. Theses analyses also allow determining the failure time of this circuit. Statistical dispersions on ICs performances, due to the used manufacturing process, have been taking into account in order to assess their impact on failure time dispersions of a ICs lot. The method has been applied on two degradation mechanisms: hot carriers and radiations
Baron, Alexandre. „Optique Non-Linéaire dans les structures semi-conductrices à fort confinement du champ“. Phd thesis, Université Paris Sud - Paris XI, 2010. http://tel.archives-ouvertes.fr/tel-00573319.
Der volle Inhalt der QuelleJhaidri, Mohamed Amine. „Techniques de synchronisation à très faible SNR pour des applications satellites“. Thesis, Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire, 2017. http://www.theses.fr/2017IMTA0038/document.
Der volle Inhalt der QuelleIn deep space communication systems, the long distance between the spacecraft and the ground station along with the limited capacity of the on-board power generator result a very low signal to noise ratio (SNR). However, such transmission still possible by using near Shannon limit error correction codes (Turbo code and LDPC code). Nevertheless, to take advantage of this coding gain, the coherent demodulation is mandatory, and the carrier phase synchronization must be reliable at more restrictive SNR. At very low SNR, current synchronization systems are limited and unable to provide the required performances. Our goal is to improve the reliability of the receiver synchronization stage under very difficult conditions of a very low SNR, a variable Doppler effect (Doppler rate) and a blind transmission. This thesis deals with the problem of carrier phase synchronization for the downlink of a Deep Space transmission. After the study of the existing solutions, we selected the phase locked loop (Phase Locked Loop: PLL). In an industrial context, PLL offers the best trade-off between complexity and performance. Several phase detectors based on the maximum likelihood criterion were considered and characterized by their S-curves. Based on the equivalent models, we have developed a new study of the non-linear acquisition phase of a second-order PLL with a semi-sinusoidal phase error detector. The second part of the thesis was dedicated to the antennas combining techniques. These methods aim to improve the link budget of the transmission and offer more flexibility. At the end of this part, we proposed a new antennas combining scheme that improves the operating threshold of existing systems
Long, Shihe. „Modélisation du canal intra-bâtiment et transmission haut-débit pour les communications optiques dans le spectre visible“. Thesis, Ecole centrale de Marseille, 2016. http://www.theses.fr/2016ECDM0005.
Der volle Inhalt der QuelleVisible Light Communications (VLC) have attracted particular attention in the research community since a few years as a promising solution for high-speed indoor wireless networks. By exploiting the existing solid-state light-emitting diode (LED) lighting infrastructure, VLC offer numerous advantages such as a large unlicensed bandwidth, transmission security, and immunity to electro-magnetic interference compared to their radiofrequency counterparts. Within the context of indoor VLC, the multipath propagation channel and the non-ideal characteristics of the commercial white LEDs cause the main limitations for achieving high data-rate transmission. The objective of this thesis is to investigate the true impact of these limitations on the data transmission and to propose efficient signal processing solutions to mitigate their adverse effects. We start by the study of the indoor VLC channel impulse response by developing an efficient simulation tool. We then consider evaluating the channel frequency selectivity through different metrics. Next, given the potentially frequency-selective channel and the limited modulation bandwidth of the LEDs, we investigate the suitability of employing different signal transmission techniques including optical orthogonal frequency-division multiplexing (O-OFDM) in order to achieve high data-rate transmission. Given the high peak-to-average power ratio (PAPR) of O-OFDM signals and the limited dynamic range of the LEDs, we then propose a novel transmission scheme, which consists of using carrier-less amplitude and phase (CAP) modulation together with frequency domain equalization (FDE) at the receiver. We analyze the performance of the VLC link using this technique and compare it with the O-OFDM schemes, especially by taking the non-linear characteristics of the LED into account. Lastly, we demonstrate the merits of using the CAP-FDE transmission scheme via some experimental results
Arvinte, Ionela Roxana. „Étude de l’incorporation des dopants N et Al dans des films de carbure de silicium épitaxiées en phase vapeur“. Thesis, Université Côte d'Azur (ComUE), 2016. http://www.theses.fr/2016AZUR4091/document.
Der volle Inhalt der QuelleThis work is dedicated to the investigation of intentional dopant incorporation in silicon carbide epilayers grown by chemical vapor deposition technique. The role of main process conditions (growth temperature, dopant supply, deposition rate, growth pressure and C/Si ratio) on both, Nitrogen and Aluminum incorporation was studied in details. Previous works have widely explored the characteristics of dopant incorporation, especially the nitrogen incorporation addressing a potential influence of growth equipment for the observed incorporation trends. An exhaustive experimental study of N and Al incorporation was performed for homoepitaxial 4H-SiC layers grown on Si- and C-faces of 4H-SiC substrates in our CVD setups to explore such influence. It was completed by the assessment of the structural, optical and electrical properties of the Al doped 4H-SiC films. Furthermore, the fabrication of pn diodes was tested on the grown layers. We have observed different experimental tendencies depending on dopant nature, crystal orientation and chemical environment. We conclude from these observations that the mechanism behind the experimentally obtained tendencies is widely influenced by factors such as process conditions (i.e. growth temperature and/or pressure) and the carbon coverage at the grown surface, especially on C-face
Vidal, Sébastien. „Étude théorique et expérimentale de la génération et de la mise en forme d'impulsions térahertz“. Phd thesis, Université Sciences et Technologies - Bordeaux I, 2009. http://tel.archives-ouvertes.fr/tel-00446512.
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