Dissertations / Theses on the topic 'Radiation Bias'

Nous cherchons à mettre en évidence l'influence des hétérogénéités de température, de structure ou de composition des atmosphères sur leurs observations. Dans le années à venir, de plus en plus d'appareils vont permettre l'observation par transmission des atmosphères d'exoplanètes. Toutefois, les outils numériques permettant de contraindre ces dernières reposent sur des modèles simples à une dimension. Ils supposent en effet des atmosphères ne possédant qu'une structure verticale (le climat est le même en tout point de la surface, la composition ou la température n'évolue qu'avec l'altitude). Cette approche a le mérite de permettre des calculs rapides et de contraindre les paramètres globaux de l'atmosphère avec des temps raisonnables. Ceci ne serait pas possible en l'état avec une modélisation en 3 dimensions des atmosphères, même si ce serait beaucoup plus réaliste. Ce que nous cherchons à mettre en évidence, ce sont les limites des techniques actuelles d'inversion et donc, de caractérisation des atmosphères qui seront observées. Pour cela, il fallait mettre au point un logiciel capable de résoudre le transfert radiatif au sein d'une atmosphère en 3 dimensions (et non plus 1 seul). Une fois le logiciel terminé, nous avons éprouvé l'algorithme de traitement du signal TauREx en comparant les résultats qu'il proposait à des simulations atmosphériques parfaitement contrôlées. Nous nous sommes tout principalement arrêté sur les biais découlant d'hétérogénéités de température en simulant des atmosphères avec un fort contraste jour/nuit. Ceci nous a permis de caractériser les biais découlant de ces types d'hétérogénéités, de les quantifier et de mettre l'accent sur un biais jusqu'ici très sous-estimé par la communauté, à savoir celui découlant des hétérogénéités le long de la ligne de visée. Nous avons appuyé nos propos et concentré nos efforts sur l'interprétation de l'inversion d'une simulation complexe de l'atmosphère de GJ 1214 b. La reconstitution de la chaine observationnelle : GCM (LMD), Pytmosph3R (LAB) et TauREx (UCL) ouvre les portes d'un vaste panel d'études envisageables, et notamment tout ce qui va concerner l'identification et la caractérisation des biais systématiques qui incomberont les observations à venir
Transmission spectroscopy provides us with information on the atmospheric properties at the limb, which is often intuitively assumed to be a narrow annulus aound ther planet. Consequently, the few recent studies on the effect of atmospheric horizontal heterogeneities on transmission spectra have used approaches sensitive to variations along the limb only. Here we demonstrate that the region probed in transmission – the limb – actually extends significantly toward the day and night sides of the planet. Consequently we show that thestrong day-night thermal and compositional gradients expected on synchronous exoplanets create sufficient heterogeneities across the limb to result in important systematic effects on the spectrum and bias its interpretation. To quantify these effects, we developed a 3D radiative transfer model able to generate transmission spectra of atmospheres based on 3D atmospheric structures, whether they come from a Global Climate Model or more parametrized models. We first apply this tool to a simulation of the atmosphere of GJ 1214 b toproduce synethic JWST observations and show that producing a spectrum using only atmospheric columns at the terminator results in errors greater than expected noise. This demonstrates the necessity of a real 3D approach to model data for such precise observatories.Second, we investigate how day-night temperature gradients cause a systematic bias in retrieval analysis performed with 1D forward models. For that purpose we synthesize a large set of forward spectra for prototypical HD209458 b and GJ 1214 b type planets varying the temperatures of the day and night sides as well as the width of the transition region. We then perform typical retrievalanalyses and compare the retrieved parameters to the ground truth of the input model. This study reveals systematic biases on the retrieved temperature (found to be higher than the terminator temperature) and absorber abundances. This is due to the fact that the hotter dayside is more extended vertically and screens the nightside—a result of the nonlinear properties of atmospheric transmission.These biases will be difficult to detect as the 1D profiles used in the retrieval procedure are found to provide an excellent match to theobserved spectra based on standard fitting criteria (chi2, posterior distributions). This fact needs to be kept in mind when interpretingcurrent and future data

Le sujet de ma thèse est la conception d’ASICs (Application-Specific Integrated Circuits) mixtes durcis aux radiations pour observatoires spatiaux. La thèse se déroule dans le contexte d'un futur observatoire spatial à rayons X de l’ESA, se nomme « Advanced Telescope for High ENergy Astrophysics (ATHENA) ». Les ASICs développés appartiennent à l'un des deux instruments scientifiques de cet observatoire, s’appelle « X-ray Integral Field Unit (X-IFU) », et sont dédiés à l'un des sous-systèmes de l'instrument X-IFU, le WFEE (Warm Front End Electronics).Le WFEE est un système électronique mixte comprenant principalement un amplificateur à bas bruit (LNA), un circuit de polarisation configurable pour SQUIDs, un buffer et un thermomètre. Par conséquent, mes travaux de thèse sont composés de deux parties: la partie numérique et la partie analogique.Mes contributions aux circuits numériques du WFEE sont présentées dans « Part III » de ma thèse. Elles comprennent la conception d'une nouvelle librairie des portes logiques numériques durcies aux radiations et la création d'un nouveau décodeur I2C avec ses schémas et layouts optimisés, en utilisant ma nouvelle librairie numérique. Les résultats représentatifs des essais de radiation sur les composants et les registres à 8-bit avec une telle conception durcie aux radiations sont également discutés dans « Part III » de ma thèse. Tous les circuits numériques dans les deux nouveaux ASICs «AwaXe_v2» et «AwaXe_v2.5» sont constitués de cette nouvelle librairie numérique durcie aux radiations, ainsi que ceux dans les futurs ASICs. Les décodeurs I2C optimisés ont prouvé un bon fonctionnement, testés avec les autres circuits intégrés dans «AwaXe_v2» et «AwaXe_v2.5».Mes contributions sur les circuits analogiques du WFEE sont présentées dans « Part IV ». Elles comprennent la conception d'un LNA, d'un buffer, d'une référence de courant et d'un convertisseur numérique-analogique (DAC). Le LNA est essentiel pour atteindre la résolution spectrale élevée sans précédent de 2,5 eV proposée par l'instrument X-IFU. Il a une conception originale, intégrée dans les ASICs v2 et v2.5. Il a été entièrement testée et a donné des résultats satisfaisants et cohérents. Ses performances ont été prouvées expérimentalement pour répondre à toutes les spécifications requises par le CNES. Fonctionnant dans la bande de fréquence de 1-5 MHz, il fournit un gain de tension super-linéaire de 85 V/V, une large bande passante de -1 dB à 17,5 MHz et une faible dérive de gain <350 ppm/K. Il réalise un très faible bruit à tension ≈ 0,8 nV/√Hz à l’entrée, ainsi qu’une faible fréquence de coupure de bruit 1/f <4 kHz, un bon PSRR et un bon CMRR. Le buffer utilise une conception similaire à celle du LNA et a besoin plus d’études dans les travaux futurs. La référence de courant a été entièrement testée avec une sortie de 1 mA. Grâce à sa conception originale, qui compense les références CTAT et PTAT, elle est capable de fournir un courant super stable, indépendant de la température, parfaite pour la polarisation de SQUID. Enfin, j'ai également développé un DAC à 8-bit pour la polarisation de SQUID. 8 DACs, une référence de courant et un bus série composent un circuit complet de la polarisation de SQUID d’un canal WFEE. Ce circuit a été intégré dans l’ASIC «AwaXe_v2.5» et a donné un bon résultat lors de la première mesure.En conclusion, ma thèse a produit deux ASICs pour le WFEE: «AwaXe_v2» et «AwaXe_v2.5». Les deux ASICs montrent de bonnes performances. En particulier, le dernier ASIC intègre tous les composants d'un canal WFEE, ce qui peut être considéré comme un prototype. Ainsi, il est un bon représentant de mes travaux de la thèse. En outre, les performances élevées du LNA et de la référence de courant aussi montrent le potentiel pour s’adapter à d’autres missions scientifiques similaires
The subject of my thesis is the development of radiation-hardened mixed-signal Application-Specific Integrated Circuits (ASICs) for space observatories. The thesis takes place in the context of a future X-ray space observatory of the European Space Agency, named Advanced Telescope for High ENergy Astrophysics (ATHENA). The ASICs developed belong to one of the two scientific instruments of the observatory, called X-ray Integral Field Unit (X-IFU) and are dedicated to one of the subsystems of the X-IFU instrument, the WFEE (Warm Front End Electronics).The WFEE is a mixed electronic system, mainly including a Low Noise Amplifier (LNA), a configurable SQUID bias, a buffer and a thermometer. Consequently, my thesis work is composed of two parts: the digital part and the analogue part.My contributions to the digital microelectronics of the WFEE are presented in Part III of my thesis. It includes the design of a new radiation-hardened digital library and the creation of a new I2C decoder with optimised schematic and layout, made of my new digital library. The representative radiation assessment results concerning the components and 8-bit registers with such radiation-hardened design are also discussed in Part III of the thesis. All the digital circuits of the two new ASICs “AwaXe_v2” and “AwaXe_v2.5” are made of this new radiation-hardened digital library, as well as those in the future ASICs. The optimised I2C decoders have been proved a good functioning along with the other circuits, integrated into the “AwaXe_v2” and “AwaXe_v2.5”.My contributions on the analogue circuits of the WFEE are presented in Part IV. It includes the design of an LNA, a buffer, a current reference and a Digital-to-Analog Converter (DAC). The LNA is critical for fulfilling the unprecedented high spectral resolution of 2.5 eV proposed by the X-IFU instrument. Its original design has been integrated into the ASICs v2 and v2.5, both fully tested and showing satisfying and coherent results. Its performance has been experimentally proved to fulfil all the specifications required by the CNES. Operating within the frequency band of 1-5 MHz, it provides a super-linear voltage gain of 85 V/V, with a large bandwidth of −1 dB up to 17.5 MHz and a low gain drift < 350 ppm/K. It realises an ultra-low voltage noise ≈ 0.8 nV/√Hz at the input, as well as a low 1/f noise corner frequency < 4 kHz, a good PSRR and CMRR. The buffer uses a similar design as the LNA and needs to be further studied in future work. The current reference has been fully tested with an output of 1 mA. Thanks to its original design compensating a CTAT and a PTAT reference, it has been proved to be capable of providing a super-stable temperature independent current, perfect for the SQUID bias. At last, I have also developed an 8-bit DAC for the SQUID bias. 8 DACs along with a current reference and a series bus compose a complete SQUID bias of one WFEE channel. This circuit has been integrated into the ASIC “AwaXe_v2.5” and showed a good result for the first measurement.In conclusion, my thesis has yielded two ASICs for the WFEE: “AwaXe_v2” and “AwaXe_v2.5”. Both ASICs show good performance. In particular, the last ASIC integrates all the components of one WFEE channel, which can be considered as a prototype. Thus, it is a good representative of my work. Moreover, the high performance of the LNA and the current reference also give them the potential to adapt with other similar scientific missions

Pas de résumé en français
Plasmonic circuitry is considered as a promising solution-effectivetechnology for miniaturizing and integrating the next generation ofoptical nano-devices. The realization of a practical plasmonic circuitry strongly depends on the complete understanding of the propagation properties of two key elements: surface plasmons and electrons. The critical part constituting the plasmonic circuitry is a waveguide which can sustain the two information-carriers simultaneously. Therefore, we present in this thesis the investigations on the propagation of surface plasmons and the co-propagation of surface plasmons and electrons in single crystalline metal nanowires. This thesis is therefore divided into two parts. In the first part, we investigate surface plasmons propagating in individual thick penta-twinned crystalline silver nanowires using dual-plane leakage radiation microscopy. The effective index and the losses of the mode are determined by measuring the wave vector content of the light emitted in the substrate. Surface plasmon mode is determined by numerical simulations and an analogy is drawn with molecular orbitals compound with similar symmetry. Leaky and bound modes selected by polarization inhomogeneity are demonstrated. We further investigate the effect of wire geometry (length, diameter) on the effective index and propagation losses. On the basis of the results obtained during the first part, we further investigate the effect of an electron flow on surface plasmon properties. We investigate to what extend surface plasmons and current-carrying electrons interfere in such a shared circuitry. By synchronously recording surface plasmons and electrical output characteristics of single crystalline silver and gold nanowires, we determine the limiting factors hindering the co-propagation of electrical current and surface plasmons in these nanoscale circuits. Analysis of wave vector distributions in Fourier images indicates that the effect of current flow on surface plasmons propagation is reflected by the morphological change during the electromigration process. We further investigate the possible crosstalk between co-propagating electrons and surface plasmons by applying alternating current bias

Plasmonic circuitry is considered as a promising solution-effectivetechnology for miniaturizing and integrating the next generation ofoptical nano-devices. The realization of a practical plasmonic circuitry strongly depends on the complete understanding of the propagation properties of two key elements: surface plasmons and electrons. The critical part constituting the plasmonic circuitry is a waveguide which can sustain the two information-carriers simultaneously. Therefore, we present in this thesis the investigations on the propagation of surface plasmons and the co-propagation of surface plasmons and electrons in single crystalline metal nanowires. This thesis is therefore divided into two parts. In the first part, we investigate surface plasmons propagating in individual thick penta-twinned crystalline silver nanowires using dual-plane leakage radiation microscopy. The effective index and the losses of the mode are determined by measuring the wave vector content of the light emitted in the substrate. Surface plasmon mode is determined by numerical simulations and an analogy is drawn with molecular orbitals compound with similar symmetry. Leaky and bound modes selected by polarization inhomogeneity are demonstrated. We further investigate the effect of wire geometry (length, diameter) on the effective index and propagation losses. On the basis of the results obtained during the first part, we further investigate the effect of an electron flow on surface plasmon properties. We investigate to what extend surface plasmons and current-carrying electrons interfere in such a shared circuitry. By synchronously recording surface plasmons and electrical output characteristics of single crystalline silver and gold nanowires, we determine the limiting factors hindering the co-propagation of electrical current and surface plasmons in these nanoscale circuits. Analysis of wave vector distributions in Fourier images indicates that the effect of current flow on surface plasmons propagation is reflected by the morphological change during the electromigration process. We further investigate the possible crosstalk between co-propagating electrons and surface plasmons by applying alternating current bias

Obtenir une estimation du taux d'erreurs induit par les phénomènes de basculement de bit (soft error rate, SER) des équipements électroniques est d'un intérêt grandissant. Les standards publiés traitent principalement de la qualification des circuits de type mémoire. Il n'y a pas d'accord sur les méthodes de qualification des microprocesseurs. Dans ce contexte, cette thèse s'attache à définir une méthodologie permettant de prédire le SER d'un processeur à l'aide d'une approche en trois étapes : -En définissant une méthode de test sous radiation permettant d'obtenir de façon précise la sensibilité du circuit au rayonnement ionisant ; -En présentant une analyse détaillée des mesures, dont le but est d'extraire un modèle statistique d'un test accéléré ; -En utilisant cette empreinte statistique pour reproduire à l'aide d'injection de fautes le comportement du circuit étudié afin de prédire le comportement d'une application quelconque exécutée par le processeur
Estimating the soft error rate (SER) of digital equipment is a major concern : while the SER of a single bit can be extremely low, the increasing amount of bits per device combined with their use in safety-critical applications makes the SER evaluation an important milestone before introducing a new technology to the market or using it in a space application. To derive the SER of a device, the commonly adopted strategy consists in exposing the tested part to either a particle beam (accelerated test) or to its natural environment while it carries on a given activity. The difficult point is to exercise the tested chip in a way as representative as possible of the one that will be used in the final environment Standards have been published, defining requirements and procedures for SER testing of integrated circuits. However, the procedures presented in these texts apply primarily to memory devices. There is not such an agreement on the SER evaluation of microprocessors. Ln this context, the work done in this Ph. D. Defines a methodology to measure and predict the SER of a processor using a three steps approach : By defining a correct static test strategy allowing to measure the cross-section of the processor's memory elements ; By presenting a detailed analysis of radiation ground testing data, aiming at extracting a statistical model of an accelerated radiation ground test, that is where and when SEUs do occur in the studied processor ; By usina this statistical footDrint and fault iniection techniaues to studv the behaviour of any application executed by the processor

Neste trabalho foi elaborado um microcontrolador 8051 tolerante à radiação, usando para isso técnicas de recomputação de instruções. A base para este trabalho foi a descrição VHDL desse microcontrolador, sendo proposto o uso de sensores de radiação, Bulk-BICS, e códigos de proteção de erros para os elementos de memória, como forma de suporte à técnica apresentada. Inicialmente serão abordados sucintamente a origem e os efeitos prejudiciais da radiação nos dispositivos eletrônicos, motivando a realização deste trabalho. Serão mostrados em detalhes os passos para implementar a técnica de recomputação, que consiste em monitorar os sensores e, ao ser detectado um pulso transiente, fazer o processador reler a última instrução e executá-la novamente, a fim de mitigar o efeito do SET (Single Event Transient). Para isso a manipulação do contador de programa (PC) e o apontador de pilha (SP) são fundamentais. Durante esse processo também deve ser garantido que nenhum dado, potencialmente corrompido, seja armazenado na memória. Contra SEUs (Single Event Upsets) é pressuposto que todos os elementos de memória do microcontrolador estão protegidos através de algum código de correção de erros, assunto já pesquisado por outros autores. Na seqüência serão apresentadas várias simulações realizadas, onde é possível ver o processo de recomputação sendo iniciado a partir da incidência de partículas geradas através de um testbench. Por fim será feita uma comparação entre o 8051 original e o protegido, mostrando dados de área, freqüência de operação e potência de cada um.
This work presents a radiation hard 8051 microcontroller, designed using instruction recomputation techniques. The basis for this work was the VHDL description of the microcontroller. To make the microcontroller radiation hard, built in radiation sensors, called Bulk-BICS, were use to protect the combinational logic blocks. Codes for error detection and correction were used to protect the memory elements. Initially, this work discusses the sources of ionizing radiation and its harmful effects on digital integrated circuits, showing the motivation for this work. Next, the details of the implemented instruction re-computation technique are shown. It consists in monitoring the radiation sensors and, if the incidence of ionizing radiation is detected, the processor reads the last instruction and executes it again, in order to mitigate the effect of a single event transient (SET). In order to implement this re-computation, the manipulation of the program counter (PC) and stack pointer (SP) is essential. During this process it must be guaranteed that any data, potentially corrupted, will not be stored in memory. Regarding radiation effects on memory elements (Single Event Upsets-SEUs), it is assumed that all memory elements of the microcontroller are protected by some error detection and correction code, a topic previously studied by other authors. Finally, several simulations will be shown, where it is possible to see the evolution of the re-computation process, from the detection of the incidence of ionizing radiation (incidence generated by a testbench) to the full re-computation of the instruction. Finally, a comparison is made between the performance of the original 8051 and the radiation hardened version, showing overheads of area, frequency of operation and power.

Les résultats de différentes expériences du CNES (Centre National d’Études Spatiales) embarquées sur satellites montrent que des composants SRAM et SDRAM subissent des erreurs atypiques, qui se caractérisent par une fraction d’emplacements mémoire présentant des erreurs récurrentes. Ces erreurs non-catégorisées représentent la quasi-totalité des erreurs détectées sur ces mémoires. Une revue interne du CNES a déterminé que ces erreurs étaient dues aux radiations présentes dans l’environnement spatial (protons, électrons, ions lourds). Cette thèse s’attache à reproduire ces erreurs atypiques au sol en utilisant des moyens d’irradiation et des accélérateurs de particules, à les caractériser ainsi qu’à expliquer le mécanisme physique menant à l’apparition de ces cellules endommagées. Le mécanisme physique que nous proposons est cohérent avec les données obtenues sous faisceau de particules et soutenu par nos simulations de type TCAD
CNES’s onboard experiment results on several satellites have demonstrated that on SRAM and SDRAM memories, a fraction of words suffers from unknown errors that increase the afflicted words’ rate of error by orders of magnitude compared to other words. CNES’s experts found that these errors were due to the space radiation environment (proton, electrons, heavy ions).The main goals of this Ph.D. thesis are to successfully recreate such errors at ground level using irradiation facilities and particle accelerators, to investigate their behavior and finally, to submit a physical mechanism for memory cell degradation under irradiation, both coherent with experimental data and data obtained from TCAD simulations

Ce travail contribue à établir une méthode de test permettant de déterminer l'impact des radiations naturelles sur le fonctionnement de circuits intégrés de type FPGA SRAM-Based. L'étude des erreurs potentielles liées aux événements singuliers ou multiples ayant lieu dans la mémoire de configuration sera faite à l'aide d'expériences d'injection de fautes réalisées avec un équipement laser. Il s'appuie sur une présentation du contexte scientifique ainsi qu'une description de l'architecture complexe des FPGA SRAM-Based et des moyens de tests usuels. Des expériences d'injection de fautes à l'aide d'un laser sont menées sur plusieurs familles de composants afin de réaliser des tests statiques de la mémoire de configuration et de trouver les liens avec le fonctionnement de l'application. Elles révèlent ainsi l'organisation et la sensibilité des cellules SRAM de configuration. Des tests dynamiques en accélérateur de protons permettent de définir des critères de criticité des bits de configuration en fonction de leur impact sur l'application. Un outil de prédiction du taux d'erreur critique a été développé et validé à partir de cette classification
This work aims at designing a test methodology to analyze the effect of natural radiation on FPGA SRAM-based chipsets. Study of likely errors due to single or multiple events occurring in the configuration memory will be based on fault-injection experiments performed with laser devices. It relies on both a description of scientific background and a description of complex architecture of FPGA SRAM-Based and usual testing apparatus. Fault injection experiments with laser are conducted on several classes of components in order to perform static tests of the configuration memory and identify the links with the application. It shows the organization and sensitivity of SRAM configuration cells. Criticity criteria for configuration bits have been specified following dynamic tests in protons accelerator, in regard to their impact on the application. From this classification was developed a predicting tool for critical error rate estimation

The traditional radiation testing of space electronics has been used for more than fifty years to support the radiation hardness assurance. Its typical goal is to ensure reliable operation of the spacecraft in the harsh environment of space. This PhD research looks into the radiation testing from a different perspective; the goal is to develop radiation testing methods that are focused not only on the reliability of the components but also on a continuous radiation-induced degradation of their performance. Such data are crucial for the understanding of the impact of radiation on the measurement uncertainty of data acquisition systems onboard research space missions.

Este trabalho apresenta o desenvolvimento de um sensor de corrente transiente destinado a detectar a ocorrência de um evento transiente causado pela incidência de radiação ionizante em um circuito integrado. Iniciando com uma descrição dos efeitos da radiação sobre os circuitos integrados e dos tipos de radiação de interesse, os fundamentos da técnica Bulk- BICS são apresentados e as propostas existentes na literatura são expostas e avaliadas, com ênfase no sensor que utiliza a célula de memória dinâmica DynBICS, resultado de um trabalho prévio e do qual se dispõe de amostras fabricadas. Sobre essas amostras são efetuados testes elétricos, um ensaio de dose total irradiada TID e um ensaio de estimulação laser, cujos resultados são apresentados e confirmam a funcionalidade da topologia da célula de memória dinâmica aplicada a circuitos Bulk-BICS. Em seguida, é apresentada a topologia da célula de memória integrativa como uma evolução da célula de memória dinâmica e propõe-se o circuito de um novo sensor Bulk-BICS baseado na nova célula. O funcionamento elétrico do circuito desse novo sensor TRIBICS é avaliado através de simulação de circuitos determinando-se a sensibilidade e o tempo de resposta do sensor utilizando-se pulsos de corrente em dupla exponencial. É feita uma análise do funcionamento da célula de memória estática e, através de uma comparação de desempenho entre as células de memória estáticas utilizadas em três circuitos propostos e a célula de memória integrativa, utilizando um modelo simplificado, mostra-se que a célula de memória integrativa é mais rápida e sensível do que as contrapartes estáticas O sensor TRIBICS é então simulado em conexão com um modelo de dispositivo, sendo antes apresentados os modelos TCAD do inversor utilizado como alvo da incidência da radiação nas simulações. São apresentados resultados obtidos individualmente para o transistor NMOS e para o transistor PMOS, nos quais se mostra a formação de um canal condutivo entre dreno e fonte durante o SET. Mostra-se, também, que os resultados obtidos com a simulação de dispositivos não concorda com aqueles proporcionados pela simulação de circuitos no tocante à divisão das correntes transitórias entre dreno, fonte e substrato. O resultado das simulações de dispositivo efetuadas com os modelos TCAD em modo misto com o circuito TRIBICS descrito em SPICE mostram a relação entre a transferência de energia da irradiação LET e a efetiva deteção do SET provocado, em função da distância entre os contatos de bulk ou substrato, permitindo determinar a máxima distância entre contatos para 100% de certeza na deteção do SET. Com isso, obtém-se uma estimativa do número de transistores que pode ser monitorado pelos Bulk-BICS. É proposta a estratégia de implementação dos Bulk-BICS na forma de uma standard cell a ser posicionada entre os grupos de transistores sob monitoração, e uma estimativa da relação entre as áreas dos transistores monitorados e do Bulk-BICS é apresentada. Por fim, é estudada a questão da fabricação dos Bulk-BICS no mesmo substrato dos transistores monitorados e uma maneira de fazê-la é proposta. Os resultados encontrados permitem definir a viabilidade e a eficácia da técnica Bulk-BICS como forma de deteção de eventos transientes em sistemas digitais.
A current sensor to detect the occurrence of a single-event transient that is caused by the incidence of ionizing radiation in an integrated circuit is presented. Radiation of interest and their effects on the integrated circuits are discussed. Fundamentals of the Bulk-BICS technique and the circuits proposed in the literature to implement this technique are discussed and evaluated, with emphasis on the dynamic memory cell-based circuit DynBICS, which was developed as a previous work and with fabricated samples available. Experimental results obtained from a series of electrical tests, a TID test, and a laser-stimulated test that were conducted on a number of fabricated and packaged samples are presented. The results confirm that the dynamic memory cell is suitable and robust enough to be used in Bulk-BICS circuits. Next, evolution of the dynamic memory cell into an integrative memory cell is discussed and the circuit of a Bulk-BICS using this new memory cell topology is presented. The electrical operation of this new sensor TRIBICS is evaluated using circuit simulations. By using double-exponential current pulses, both the sensitivity and the response time are determined. The static memory cell operation is analyzed and a comparison of performance between static and integrative cells is performed using a simplified model. The results show that the integrative memory cell is faster and more sensitive than the static cells used in three state-ofthe- art sensors published in literature Then the TRIBICS sensor is simulated connected to a TCAD-modeled device, comprising an inverter, which is used as a target for radiation impact. TCAD models are previously presented and the results obtained when the PMOS and NMOS transistors are separately excited by radiation show the formation of a conductive link between drain and source regions during the occurrence of SET. The simulations also show that the results obtained by using TCAD simulations do not agree with the ones obtained by using circuit simulation regarding the current share among drain, source and bulk during the SET. Mixed-mode simulations using the TCAD models in conjunction of TRIBICS circuits described in SPICE show the relationship between LET and the effective SET-detection with the inter-tap distance as a parameter, and allows to determine the inter-tap distance for 100% of SET detection efficiency. Based on these results, an estimate of how many transistors can be monitored by the Bulk-BICS is obtained. It is proposed to implement the Bulk-BICS as a standard cell, to be positioned in between the standard cell that compose a digital circuit and the area overhead necessary to implant the sensors in a real circuit is estimated. The problem on how to manufacture the Bulk-BICS circuit in the same substrate of the monitored transistors is studied and a solution is proposed. The results show the viability and effectiveness of the Bulk-BICS technique, as a means to detect single-event transients in digital systems.

Deux nouvelles familles de complexes de cuivre(I) cationiques, de formules [Cu(NHC)(N^N)][X] et [Cu(P^P)(N^N)][PF6], ont été synthétisées avec des ligands 2,2’ bis pyridyl pontés, chélates à six chaînons, facilement modulables. Ces complexes présentent des émissions à l’état solide centrées entre 455 et 520 nm (bleu à vert), avec de larges décalages de Stokes et des rendements quantiques pouvant atteindre 0,86. De plus, l’émission via un phénomène de fluorescence retardée activée thermiquement (TADF) a été prouvée pour les complexes [Cu(NHC)(N^N)][X]. Les premiers scintillateurs plastiques dopés avec des complexes de cuivre(I) détectant les radiations nucléaires de type gammas ont été obtenus avec des complexes de formule générale [Cu(P^P)(N^N)][PF6]. Les complexes de formule [Cu(NHC)(N^N)][X] ont permis l’obtention des premières Cellules Electrochimiques Luminescentes (LECs) émettant dans le bleu et incorporant des complexes de cuivre(I). Enfin, les complexes de formule [Cu(NHC)(N^N)][X] à ligand 2,2’ dipyridylamine présentent une activité cytotoxique envers différentes lignées de cellules cancéreuses et apportent la possibilité d’une action ciblée sur les cellules tumorales via l’ajout d’un vecteur. La polyvalence de ces complexes de cuivre(I) repose sur les ligands 2,2’-bis-pyridyl pontés, chélates à six chaînons, dont la synthèse est facile d’accès et les propriétés électroniques et structurales sont modulables
New cationic copper(I) complexes of general formula [Cu(NHC)(N^N)][X] and [Cu(P^P)(N^N)][PF6] were developed with 6-membered-ring 2,2’-bis-pyridyl derivatives as ligand. These complexes exhibited blue (420 nm) to green (520 nm) emissions in solid state, with large Stokes shifts and photoluminescence quantum yields up to 0.86. Furthermore, the emission of the [Cu(NHC)(N^N)][X] complexes via a thermally activated delayed fluorescence (TADF) was demonstrated. The first plastic scintillators incorporating copper(I) complexes and detecting gamma radiations were obtained with [Cu(P^P)(N^N)][PF6] complexes. Application of the [Cu(NHC)(N^N)][X] complexes to the LEC technology led to the first copper(I)-based blue emitting device. In the last chapter, we also demonstrated that copper(I) complexes [Cu(NHC)(N^N)][X] bearing a 2,2’-dipyridylamine as N^N ligand exhibited high cytotoxycity against different cancer cells lines. These complexes paved the way for the design of a new type of copper(I) anti-cancer agents with the opportunity to increase the selectivity against cancer cells via a vectorization of the N^N ligand. The versatility of these copper(I) complexes demonstrated in this work relied on the easy to handle and highly modular 2,2’-bis-pyridyl ligands

This master´s thesis deals with the properties of gel polymer electrolytes, brief characteristics of other types of electrolytes and materials that are used for preparing polymer electrolytes. The thesis explains the use of the gel electrolytes in practice, the current conduction in the electrolytes and the properties of ionic liquids, and flame retardants. This thesis also focuses on methods of measurement of mechanical properties of gel polymer electrolytes. The practical part is focused on preparation of methacrylate gel electrolytes and their modifications with the use of flame retardant - triethyl phosphate (TEP) and ionic liquid - 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (Emim TFSI). In this part there are evaluations of their potential funcionality (potential window) and specific conductance conductivity using the method LSV (linear sweep voltammetry) and impedance spectroscopy. The practical part also includes a thermal analysis of selected samples by TGA, DTA and EGA methods.

La Modulation Spatiale MIMO (Multiple Input Multiple Output) SM-MIMO est apparue pour répondre à la fois aux besoins croissants de forts débits binaires et d’efficacité énergétique des dispositifs connectés pour l’Internet des objets (IoT) et les réseaux sans fil (5G, Wi-Fi, etc...). Elle se caractérise par l’emploi d’un réseau d’émetteurs. Chaque élément du réseau d’émetteurs code pour un symbole particulier. Mais cette solution n’est pas envisageable pour l’implémentation de petits objets connectés. Dans la première partie de la thèse, nous avons développé plusieurs antennes reconfigurables. Pour nos applications, une antenne reconfigurable possède différents diagrammes de rayonnement codant chacun pour un symbole binaire particulier. Les premiers prototypes fabriqués reposent sur une ligne méandre en couplage avec des résonateurs parasites. Pour accroître la compacité de l’antenne, nous avons conçu une antenne à anneaux fendus générant 8 différents diagrammes de rayonnement décorrélés à la fréquence de 2.45GHz. Pour estimer la fiabilité de la transmission radio, nous calculons numériquement et évaluons expérimentalement la probabilité d’erreurs de transmission (BER) en fonction du rapport Signal-sur-Bruit (SNR). Nos antennes présentent des résultats prometteurs dans l’implémentation d’une communication numérique en environnement indoor. Dans une deuxième partie de la thèse, pour transmettre une donnée vers un récepteur, nous avons exploité les ondes électromagnétiques ambiantes comme sources d’opportunité. Cette nouvelle technique de communication numérique repose sur un rétrodiffuseur capable de commuter entre différents états d’impédance et module le champs électrique ambiant. Ces réseaux sont sujets à des interférences. En particulier, on montre que le diagramme d’interférences entre une source d’onde, un rétrodiffuseur et un récepteur dépend fortement de leur localisation dans l’espace. Nous estimons le BER de la communication par rétrodiffusion et démontrons qu’il dépend du contraste de puissance estimé par le récepteur. A la fin du manuscrit, on donne des axes de recherche possibles pour améliorer la sensibilité du récepteur vis-à-vis du rétrodiffuseur et augmenter le débit binaire de cette communication numérique
The Spatial Modulation MIMO (Multiple Input Multiple Output) SM-MIMO has emerged to meet both the growing need for high data rates and energy efficiency of connected devices for the Internet of Things (IoT) and wireless networks (5G , Wi-Fi, etc ...). It is characterized by the use of a network of transmitters. Each element of the transmitter network encodes a particular symbol. But this solution is not conceivable for the implementation of small connected objects. In the first part of the thesis, we have developed several reconfigurable antennas. For our purposes, a reconfigurable antenna has different radiation patterns whose each of them codes for a particular binary data. The first prototypes manufactured are based on a meander line in coupling with parasitic resonators. To increase the antenna’s compactness, we have developed a split-ring antenna generating 8 different decorrelated radiation patterns at the frequency of 2.45GHz. To estimate the reliability of the radio transmission, we numerically compute and experimentally evaluate the probability of errors of transmission (BER) as a function of the Signal-to-Noise Ratio (SNR). Our antennas show promising results in the implementation of a digital communication in indoor environment. In the second part of the thesis, in order to transmit data to a receiver, we have exploited ambient electromagnetic waves as sources of opportunity. This new digital communication technique is based on a backscatter capable of switching between different states of impedence and thus modulating the ambient electric field. These networks are subject to deep fadings. In particular, it is shown that the interference pattern between a wave source, a backscatter and a receiver strongly depends on their location in space. We estimate the BER of backscatter communication and demonstrate that it depends on the power of contrast estimated by the receiver. At the end of the manuscript, possible search axes are given to improve the sensitivity of the receiver towards the backscatter and to increase the data rate of this digital communication

An increasing number of GPS applications require a high level of accuracy. To reduce the error contributed by the GPS ephemerides, an accurate modeling of the forces acting on GPS satellites is necessary. These forces can be categorized into gravitational and non-gravitational forces. The non-gravitational forces are a significant contribution to the total force on a GPS satellite but they are still not fully understood whereas the gravitational forces are well modeled. This study focuses on two non-gravitational forces: Solar Radiation Pressure (SRP) and the y-bias force. Different SRP models are available in the University of Texas Multi-Satellite Orbit Determination Program (MSODP). The recently developed University College London model was implemented for the purpose of this study. Several techniques to compute parameters associated with SRP models and the y-bias force during an orbit prediction were examined. Using the International GNSS Service (IGS) precise ephemerides as a reference, five different models were compared in the study. Satellite Laser Ranging (SLR) residuals were also studied to validate the approach. Results showed that the analytical UCL model performed as well as a purely empirical model such as the Extended CODE model. This is important since analytical models attempt to represent the physical phenomena and thus might be better suited to separate SRP from other forces. The y-bias force was then shown to have a once per revolution effect. The time evolution of the y-bias was found to be dependent on the SRP model used, the satellite Block type, the orbital plane, and the attitude of the satellite which suggests that estimates of y-bias contain errors from other sources, particularly the SRP models. The dependency of the y-bias evolution on the orbital plane suggests that the orientation of the plane towards the Sun is important.
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Previous studies have demonstrated the sensitivity of the amplitude of the microwave radiation-induced magnetoresistance oscillations to the microwave polarization. These studies have also shown that there exists a phase shift in the linear polarization angle dependence. But the physical origin of this phase shift is still unclear. Therefore, the first part of this dissertation analyzes the phase shift by averaging over other small contributions, when those contributions are smaller than experimental uncertainties. The analysis indicates nontrivial frequency dependence of the phase shift. The second part of the dissertation continues the study of the phase shift and the results suggest that the specimen exhibits only one preferred radiation orientation for different Hall-bar sections. The third part of the dissertation summarizes our study of the Hall and longitudinal resistance oscillations induced by microwave frequency and dc bias at low filling factors. Here, the phase of these resistance oscillations depends on the contact pair on the device, and the period of oscillations appears to be inversely proportional to radiation frequency.

Obtenir une estimation du taux d'erreurs induit par les phénomènes de basculement de bit (soft error
rate, SER) des équipements électroniques est d'un intérêt grandissant. Les standards publiés traitent principalement de la qualification des circuits de type mémoire. Il n'y a pas d'accord sur les méthodes de qualification des microprocesseurs. Dans ce contexte, cette thèse s'attache à définir une méthodologie permettant de prédire le SER d'un processeur à l'aide d'une approche en trois étapes: 1) En définissant une méthode de test sous radiation permettant d'obtenir de façon précise la sensibilité du circuit au rayonnement ionisant; 2) En présentant une analyse détaillée des mesures, dont le but est d'extraire un modèle statistique d'un test accéléré; 3) En utilisant cette empreinte statistique pour reproduire à l'aide d'injection de fautes le comportement du circuit étudié afin de prédire le comportement d'une application quelconque exécutée par le processeur.

Das entwickelte Bildgeführte Präzisionsbestrahlungsgerät für Kleintiere (engl. Small Animal Image-Guided Radiation Therapy – SAIGRT) dient der schnellen, hochauflösenden Röntgenbildgebung und präzisen, konformalen Bestrahlung von Kleintieren im Rahmen präklinischer in-vivo Experimente für die translationale Krebsforschung. Speziell programmierte Softwares zur Gerätesteuerung sowie zur Bildkorrektur- und Bildrekonstruktion auf dem zentralen leistungsfähigen Arbeitsplatz-PC stellen alle Gerätefunktionen zur Verfügung und ermöglichen durch automatisierte Abläufe und intuitive grafische Nutzeroberflächen eine einfache, sichere Bedienung. Für die Bestrahlungsplanung wird eine vollwertige, aus der humanen klinischen Strahlentherapie adaptierte 3D-Bestrahlungsplanungssoftware eingesetzt, die etablierte Werkzeuge für den Transfer und die Koregistrierung multimodaler Bilddaten, die Konturierung und Segmentierung von Zielvolumina und Risikoorganen sowie die Erstellung und Validierung von Bestrahlungsplänen enthält. Die resultierende Dosisverteilung wird darin basierend auf dem individuellen CT-Datensatz des Versuchstieres und einem auf das SAIGRT angepassten Maschinenmodell mittels eines Monte-Carlo-Algorithmus exakt und realitätsnah simuliert. Durch geometrische Kalibrierungen und vielfältige Basisdatenmessungen für die Bildgebung und Bestrahlung im Rahmen der Gerätekommissionierung ist eine Zielgenauigkeit von ca. ±0,1 mm mit hoher geometrischer Abbildungstreue und guter Bildqualität bei Bildgebungsdosen vergleichbar denen klinischer Radiografie- und CT-Geräte möglich. Die Dosisverteilung zur Bestrahlung der Versuchstiere spiegelt bei der definierten Strahlungsqualität größenskaliert die humane Strahlentherapie mit hochenergetischer Photonenstrahlung von klinischen Linearbeschleunigern wider. Ein umfassendes Qualitätssicherungsprogramm bestehend aus regelmäßiger Wartung und wiederkehrenden Konstanzprüfungen der Bildgebung und Bestrahlung sichert dauerhaft den technisch einwandfreien Zustand und die ordnungsgemäße Verfügbarkeit aller Gerätefunktionen in gleichbleibender Güte. Das SAIGRT ist somit nachweislich geeignet, bildgeführte Bestrahlungen mit einem Ablauf analog dem einer modernen klinischen Strahlentherapie am Menschen in präklinischen in-vivo Experimenten präzise an Kleintieren zu applizieren. Es leistet dadurch einen essentiellen Beitrag zur translationalen Krebsforschung in Dresden, indem die klinische Situation realistischer modelliert und so potenziell die Übertragbarkeit der Ergebnisse auf Krebspatienten verbessert werden kann.
The Small Animal Image-Guided Radiation Therapy (SAIGRT) platform facilitates fast, high resolution X-ray imaging and precise, conformal irradiation of small animals in preclinical in-vivo experiments for translational cancer research. Dedicated software for device control as well as image correction and reconstruction on a central high performance PC provide all device functions and allow simple and safe operation by automated procedures and intuitive graphical user interfaces. A fully 3D treatment planning software adapted from human clinical radiation therapy is used for treatment planning, containing established tools and methods for the transfer and registration of multimodality imaging data, contouring and segmentation of target volumes and organs at risk as well as creation and evaluation of treatment plans. Based on an individual CT scan of the small animal and a machine model adapted for the SAIGRT, the resulting dose distribution is simulated by a Monte-Carlo algorithm in a precise and realistic manner. Geometrical calibrations as well as manifold basic data measurements for X-ray imaging and irradiation during commissioning resulted in a targeting and imaging accuracy of about ±0.1 mm, a correct representation of imaging geometry and a good image quality with imaging doses comparable with those of clinical radiography and CT systems. Dose distribution of the defined beam quality used for irradiation of small animals reflects a downsized human radiation therapy using high energy photon beams of clinical linear accelerators. A comprehensive quality assurance program comprising regular maintenance and periodic constancy tests of X-ray imaging and irradiation ensures permanent technically perfect condition and proper availability of all implemented functions in a stable high quality. The SAIGRT platform is feasible for image-guided irradiations precisely applied to small animals in preclinical in-vivo experiments using a workflow of modern human radiation oncology. Thus, it significantly contributes to translational cancer research by more realistic modelling the clinical situation and potentially brings the results closer to their clinical implementation.