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Streptococcus suis is part of the pig commensal microbiome but strains can also be pathogenic, causing pneumonia and meningitis in pigs as well as zoonotic meningitis. According to genomic analysis, S. suis is divided into asymptomatic carriage, respiratory and systemic strains with distinct genomic signatures. Because the strategies to target pathogenic S. suis are limited, new therapeutic approaches are needed. The virulence factor S. suis adhesin P (SadP) recognizes the galabiose Gal alpha 1-4Gal-oligosaccharide. Based on its oligosaccharide fine specificity, SadP can be divided into subtypes P-N and P-O. We show here that subtype P-N is distributed in the systemic strains causing meningitis, whereas type P-O is found in asymptomatic carriage and respiratory strains. Both types of SadP are shown to predominantly bind to pig lung globotriaosylceramide (Gb3). However, SadP adhesin from systemic subtype P-N strains also binds to globotetraosylceramide (Gb4). Mutagenesis studies of the galabiose-binding domain of type P-N SadP adhesin showed that the amino acid asparagine 285, which is replaced by an aspartate residue in type P-O SadP, was required for binding to Gb4 and, strikingly, was also required for interaction with the glycomimetic inhibitor phenylurea-galabiose. Molecular dynamics simulations provided insight into the role of Asn-285 for Gb4 and phenylurea-galabiose binding, suggesting additional hydrogen bonding to terminal GalNAc of Gb4 and the urea group. Thus, the Asn-285-mediated molecular mechanism of type P-N SadP binding to Gb4 could be used to selectively target S. suis in systemic disease without interfering with commensal strains, opening up new avenues for interventional strategies against this pathogen.

Reducing CO2 emissions is a major challenge for Europe in the years to come. Nowadays, transport is the source of 24% of global CO2 emissions. Aviation accounts for only 2% of global CO2 emissions. However, air traffic is booming and concerns are emerging. For instance, CO2 emissions from air traffic have increased by 61% in Sweden since the 1990s. This explains the emergence of the "Flygskam" movement which is spreading in more and more European countries. It is in this context that the European Union launched in September 2016 the project Hybrid Aircraft Academic research on Thermal and Electrical Components and Systems (HASTECS). The consortium brings together different laboratories and Airbus. This project is part of the program "Clean Sky 2" which aims to develop a greener aviation. The ambitious goal is to reduce CO2 emissions and the noise produced by aircraft by 20% by 2025. To do that, the consortium is studying a serial hybrid architecture. Propulsion is provided by electric motors. Two targets are defined. In 2025, the engines must reach a power density of 5kW/kg, including the cooling system. In 2035, the power density of the engines will be doubled to reach 10kW/kg. To reach these targets, the voltage level will be considerably increased, beyond one kilovolt. The risk of electric discharges in the stators of electric motors is considerably increased. The objective of this thesis is to develop a tool to assist in the design of the primary Electrical Insulation System (EIS) of the stator of an electric motor controlled by a converter. It is organized in 5 parts. The first part begins by clarifying the issues and challenges of a greener aviation. The electric motor stator EIS is developed. Finally, the constraints that apply to the EIS in the aeronautical environment are identified. The second part presents the different types of electric discharges that can be found. The main risk comes from Partial Discharges (PD) which gradually deteriorate the EIS. The main mechanism for explaining the appearance of PD is the electronic avalanche. The Paschen criterion makes it possible to evaluate the Partial Discharge Inception Voltage (PDIV). Different techniques are used to detect and measure the activity of PD. Numerical models are used to evaluate the PDIV. The third part presents an original method for determining the electric field lines in an electrostatic problem. It only uses a scalar potential formulation. The fourth part presents an experimental study to establish a correction of the Paschen criterion. An electric motor winding is very far from the hypotheses in which this criterion was originally defined. Finally, the fifth part is devoted to the development of the SIE design aid tool. Graphs are generated to provide recommendations on the sizing of the various insulators in a stator slot. A reduction in the PDIV due to a combined variation in temperature and pressure is taken into account.; La réduction des émissions de CO2 est un enjeu majeur pour l'Europe dans les années à venir. Les transports sont aujourd'hui à l'origine de 24% des émissions globales de CO2. L'aviation ne représente que 2% des émissions globales de CO2. Cependant, le trafic aérien est en pleine expansion et, déjà, des inquiétudes apparaissent. A titre d'exemple, en Suède, depuis les années 1990, les émissions de CO2 dues au trafic aérien ont augmenté de 61%. Ce constat explique l'apparition du mouvement "Flygskam" qui se repend dans de plus en plus de pays Européen. C'est dans ce contexte que l'Union Européenne a lancé en septembre 2016 le projet Hybrid Aircraft Academic research on Thermal and Electrical Components and Systems (HASTECS). Le consortium regroupe différents laboratoires et Airbus. Ce projet s'inscrit dans le programme "Clean Sky 2" qui vise à développer une aviation plus verte. L'objectif ambitieux est de réduire de 20% les émissions de CO2 et le bruit produits par les avions d'ici 2025. Pour cela, le consortium étudie une architecture hybride de type série. La propulsion est assurée par des moteurs électriques. Deux cibles ont été définies. En 2025, les moteurs doivent atteindre une densité de puissance de 5kW/kg, système de refroidissement inclus. En 2035, la densité de puissance des moteurs sera doublée pour atteindre 10kW/kg. Pour atteindre ces cibles, le niveau de tension sera considérablement augmenté, au-delà du kilovolt. Le risque de décharges électriques dans les stators des moteurs électriques est considérablement accru. L'objectif de cette thèse est de mettre au point un outil d'aide au design du Système d'Isolation Electrique (SIE) primaire du stator de moteur électrique piloté par convertisseur. Elle est découpée en cinq parties. La première partie commence par préciser les enjeux et défis d'une aviation plus verte. Le SIE du stator de moteur électrique est développé. Enfin, les contraintes qui s'appliquent sur le SIE dans l'environnement aéronautique sont identifiées. La deuxième partie présente les différents types de décharges électriques que l'on peut retrouver. Le principal risque vient des Décharges Partielles (DP) qui détériorent peu à peu le SIE. Le principal mécanisme pour expliquer l'apparition des DP est l'avalanche électronique. Le critère de Paschen permet d'évaluer le Seuil d'Apparition des Décharges Partielles (SADP). Différentes techniques permettent de détecter et mesurer l'activité des DP. Des modèles numériques permettent d'évaluer le SADP. La troisième partie présente une méthode originale pour déterminer les lignes de champ électrique dans un problème électrostatique. Elle n'utilise qu'une formulation en potentiel scalaire. La quatrième partie présente une étude expérimentale pour établir une correction du critère de Paschen. Un bobinage de moteur électrique est très loin des hypothèses dans lesquelles ce critère a été originellement défini. Enfin, la cinquième partie est consacrée à l'élaboration de l'outil d'aide au design du SIE. Des abaques sont construites afin de fournir des recommandations sur le dimensionnement des différents isolants dans une encoche de stator. Une réduction du SADP due à une variation combinée de la température et de la pression est prise en compte.

Reducing CO2 emissions is a major challenge for Europe in the years to come. Nowadays, transport is the source of 24% of global CO2 emissions. Aviation accounts for only 2% of global CO2 emissions. However, air traffic is booming and concerns are emerging. For instance, CO2 emissions from air traffic have increased by 61% in Sweden since the 1990s. This explains the emergence of the "Flygskam" movement which is spreading in more and more European countries. It is in this context that the European Union launched in September 2016 the project Hybrid Aircraft Academic research on Thermal and Electrical Components and Systems (HASTECS). The consortium brings together different laboratories and Airbus. This project is part of the program "Clean Sky 2" which aims to develop a greener aviation. The ambitious goal is to reduce CO2 emissions and the noise produced by aircraft by 20% by 2025. To do that, the consortium is studying a serial hybrid architecture. Propulsion is provided by electric motors. Two targets are defined. In 2025, the engines must reach a power density of 5kW/kg, including the cooling system. In 2035, the power density of the engines will be doubled to reach 10kW/kg. To reach these targets, the voltage level will be considerably increased, beyond one kilovolt. The risk of electric discharges in the stators of electric motors is considerably increased. The objective of this thesis is to develop a tool to assist in the design of the primary Electrical Insulation System (EIS) of the stator of an electric motor controlled by a converter. It is organized in 5 parts. The first part begins by clarifying the issues and challenges of a greener aviation. The electric motor stator EIS is developed. Finally, the constraints that apply to the EIS in the aeronautical environment are identified. The second part presents the different types of electric discharges that can be found. The main risk comes from Partial Discharges (PD) which gradually deteriorate the EIS. The main mechanism for explaining the appearance of PD is the electronic avalanche. The Paschen criterion makes it possible to evaluate the Partial Discharge Inception Voltage (PDIV). Different techniques are used to detect and measure the activity of PD. Numerical models are used to evaluate the PDIV. The third part presents an original method for determining the electric field lines in an electrostatic problem. It only uses a scalar potential formulation. The fourth part presents an experimental study to establish a correction of the Paschen criterion. An electric motor winding is very far from the hypotheses in which this criterion was originally defined. Finally, the fifth part is devoted to the development of the SIE design aid tool. Graphs are generated to provide recommendations on the sizing of the various insulators in a stator slot. A reduction in the PDIV due to a combined variation in temperature and pressure is taken into account., La réduction des émissions de CO2 est un enjeu majeur pour l'Europe dans les années à venir. Les transports sont aujourd'hui à l'origine de 24% des émissions globales de CO2. L'aviation ne représente que 2% des émissions globales de CO2. Cependant, le trafic aérien est en pleine expansion et, déjà, des inquiétudes apparaissent. A titre d'exemple, en Suède, depuis les années 1990, les émissions de CO2 dues au trafic aérien ont augmenté de 61%. Ce constat explique l'apparition du mouvement "Flygskam" qui se repend dans de plus en plus de pays Européen. C'est dans ce contexte que l'Union Européenne a lancé en septembre 2016 le projet Hybrid Aircraft Academic research on Thermal and Electrical Components and Systems (HASTECS). Le consortium regroupe différents laboratoires et Airbus. Ce projet s'inscrit dans le programme "Clean Sky 2" qui vise à développer une aviation plus verte. L'objectif ambitieux est de réduire de 20% les émissions de CO2 et le bruit produits par les avions d'ici 2025. Pour cela, le consortium étudie une architecture hybride de type série. La propulsion est assurée par des moteurs électriques. Deux cibles ont été définies. En 2025, les moteurs doivent atteindre une densité de puissance de 5kW/kg, système de refroidissement inclus. En 2035, la densité de puissance des moteurs sera doublée pour atteindre 10kW/kg. Pour atteindre ces cibles, le niveau de tension sera considérablement augmenté, au-delà du kilovolt. Le risque de décharges électriques dans les stators des moteurs électriques est considérablement accru. L'objectif de cette thèse est de mettre au point un outil d'aide au design du Système d'Isolation Electrique (SIE) primaire du stator de moteur électrique piloté par convertisseur. Elle est découpée en cinq parties. La première partie commence par préciser les enjeux et défis d'une aviation plus verte. Le SIE du stator de moteur électrique est développé. Enfin, les contraintes qui s'appliquent sur le SIE dans l'environnement aéronautique sont identifiées. La deuxième partie présente les différents types de décharges électriques que l'on peut retrouver. Le principal risque vient des Décharges Partielles (DP) qui détériorent peu à peu le SIE. Le principal mécanisme pour expliquer l'apparition des DP est l'avalanche électronique. Le critère de Paschen permet d'évaluer le Seuil d'Apparition des Décharges Partielles (SADP). Différentes techniques permettent de détecter et mesurer l'activité des DP. Des modèles numériques permettent d'évaluer le SADP. La troisième partie présente une méthode originale pour déterminer les lignes de champ électrique dans un problème électrostatique. Elle n'utilise qu'une formulation en potentiel scalaire. La quatrième partie présente une étude expérimentale pour établir une correction du critère de Paschen. Un bobinage de moteur électrique est très loin des hypothèses dans lesquelles ce critère a été originellement défini. Enfin, la cinquième partie est consacrée à l'élaboration de l'outil d'aide au design du SIE. Des abaques sont construites afin de fournir des recommandations sur le dimensionnement des différents isolants dans une encoche de stator. Une réduction du SADP due à une variation combinée de la température et de la pression est prise en compte.

With the introduction of EUV lithography, the photolithographic process in 5 nm logic process can be simplified to use mostly single exposure method. In a typical 5 nm logic process, the contact-poly pitch (CPP) is 44-50 nm, the minimum metal pitch (MPP) is around 30-32 nm. And the overlay budget is estimated to be 2.5 nm (on product overlay). Although the optical resolution of a 0.33NA exposure tool (such as ASML NXE3400) can reach below 32 nm pitch, stochastics in the EUV absorption in photoresists has limited its application to smaller pitches. For the CPP mentioned above, one can use 193 nm immersion lithography with Self-Aligned Double Patterning (SADP) technique to provide good image contrast (or CDU, LWR) as well as good overlay, as for the 10 and 7 nm generations. In the BEOL, however, the 30-32 pitch cannot be realized by a single EUV exposure with enough printing defect process window. If this pitch is to be done by 193 nm immersion lithography, more than 6-8 exposures are needed with very complicated overlay result. For EUV, this can be done through self-aligned LELE with both good CD and overlay control. We have done an optimization of the photolithographic process parameters for the typical metal with a self-developed aerial image simulator based on rigorous coupled wave analysis (RCWA) algorithm and the Abbe imaging routine with an EUV absorption model which describes stochastics. We have calibrated our model with wafer exposure data from several photoresists under collaboration with IMEC. As we have presented last year, to accommodate all pitches under a logic design rule, as well as to provide enough CDU for the logic device performance, in DUV lithography, a typical minimum exposure latitude (EL) for the poly and metal layers can be set at, respectively, 18% and 13%. In EUV, due to the existence of stochastics, 13% EL, which corresponds to an imaging contrast of 40%, seems not enough for the metal trenches, and to obtain an imaging contrast close to 100%, which yields an EL of 31.4% means that we need to relax minimum pitch to above 41 nm (conventional imaging limit for 0.33NA). This is the best imaging contrast a photolithographic process can provide to reduce LWR and stochastics. In EUV, due to the significantly smaller numerical apertures compared to DUV, the aberration impact can cause much more pronounced image registration error, in order to satisfy 2.5 nm total overlay, the aberration induced shift needs to be kept under 0.2 nm. We have also studied shadowing effect and mask 3D scattering effect and our results will be provided for discussion.

Optical lithography, the backbone of the industry for more than 50 years, has been pushing up against a number of physical barriers that have led to massive investments in development of alternative patterning techniques. Next generation lithography, based on extreme ultraviolet source (EUV), promises to overcome these issues, enabling the advancement into sub-32-nm nodes. However, EUV lithography has been confronted with a series of material and source issues, restricting its practical use for the semiconductor industry. Alternative advanced patterning options, such as multiple patterning (MP) for lines/spaces and directed self-assembly (DSA) for vias, offer significant improvements which allow the extension of conventional optical lithography down to sub-5-nm technology nodes. Multiple patterning options introduce variations in wire dimensions and spacing, while DSA vias require strict definition of the commensurable via grouping patterns in circuits. In this PhD, we aim to: a) analyze and evaluate the variability impact of the main variants of line/space MP on circuit design and performance, b) compare the results with next generation EUV lithography, c) provide a design solution for via patterning in advanced nodes, utilizing MP and templated DSA, and d) evaluate the provided solution with respect to its impact on circuit performance. In order to assess the impact of process variation, we developed a circuit-level variability analysis framework. We use this framework to generate statistical distributions of circuit performance metrics for logic circuits and SRAM arrays patterned with the considered MP options and EUV. Our results show a negligible impact of process variation related to MP options on the performance of logic circuits. This is not the case in SRAM arrays, where the impact can be substantial. For the via patterning, we propose a design method for DSA-aware via grouping and decomposition. Based on this method, we develop a fully parameterized EDA tool which can provide fast and efficient decomposition of any via layout into separate DSA-friendly masks. Running benchmark studies on a fully routed 32-bit processor, we demonstrate a drastic reduction in the number of masks per metal layer, providing a manufacturable solution with immersion ArF lithography. Finally, we show that the increased resistance variation in vias, introduced by the DSA process, has a negligible impact on circuit performance. nrpages: 210 status: published

The introduction of Multiple Patterning (MP) in sub-32nm technology nodes may pose severe variability problems in wire resistance and capacitance of IC circuits. In this paper we evaluate the impact of this variability on the performance of SRAM cell arrays based on the 10nm technology node, for a relevant range of process variation assumptions. The MP options we consider are the triple Litho-Etch (LE^3) and the Self Aligned Double Patterning (SADP), together with Single Patterning Extreme-UV (EUV). In addition to the analysis of the worst-case variability scenario and the impact on SRAM performance, we propose an analytical formula for the estimation of SRAM read time penalty, using the RC variation of the bit line and the array size as input parameters. This formula, verified with SPICE simulations, allows a fast extraction of the statistical distribution of the read time penalty, using the Monte-Carlo method. Results on each patterning option are presented and compared. ispartof: pages:609-612 ispartof: Proc. DATE vol:2015 pages:609-612 ispartof: Design, Automation and Test in Europe Conference and Exhibition (DATE) location:Grenoble, France date:9 Mar - 13 Mar 2015 status: published

International audience; We report a 20 nm half-pitch self-aligned double patterning (SADPP) process based on a resist-core approach. Line/space 20/20 nm features in silicon are successfully obtained with CDvariation, LWR and LER of 0.7 nm, 2.4 nm and 2.3 nm respectively. The LWR and LER are characterized at each technological step of the process using a power spectral density fitting method, which allows a spectral analysis of the roughness and the determination of unbiased roughness values. Although the SADP concept generates two asymmetric populations of lines, the final LLWR and LER are similar. We show that this SADP process allows to decrease significantly the LWR and the LER of about 62% and 48% compared to the initial photoresist patterns. This study also demonstrates that SADP is a very powerful concept to decrease CD uniformity and LWR especially in its low-frequency components to reach sub-20 nm node requirements. However, LER low-frequency components are still high and remain a key issue tot address for an optimized integration.