System for space materials evaluation in LEO environment

This paper describes the conception and experimental setup of a new concept for a Vacuum Ultraviolet with extreme Thermal Vacuum Cycle system and the evaluation of LEO satellites materials with the equipment. The system was developed in the framework of a study of spacecraft debris generation due to satellites materials degradation, when exposed to space environment. The study was developed in the framework of an ESA project. Its main purpose was to evaluate the characteristics and the quantity of debris resulting from surface of satellites due spacecraft materials degradation and provide input to space debris models. The experimental setup developed partially simulates the space environment, on an accelerated mode, as endured by a spaceship in Low Earth Orbit, allows the testing of materials to a Vacuum, Ultraviolet and thermal cycles. This thermal cycling provided to the sample holder was implemented using an innovative mechanical thermal switching architecture. This architecture allows temperature cycling of +200 ºC to -200 ºC without the use of LN2. The experimental setup design, manufacture and final characterization is presented

Space debris generation in GEO: Space materials testing and evaluation

The aim of this work is to evaluate what happens to the spacecraft materials beyond the spacecraft End of Life. A review of spacecraft external materials and effects of space environment is presented. This paper results from a continued study on spacecraft material degradation, and space debris formation in geostationary orbit (GEO). In this paper a 20-year GEO dose profile that combines simultaneous UV, particles irradiation and thermal cycling was applied to a set of external spacecraft materials. These materials comprised MLI assemblies, Velcros fixation and spacecraft painting. The evaluation of these external spacecraft materials, exposed to simulated space environment have confirmed the criticality of degradation of MLI, Velcros fixation and painting, with delamination mechanisms and particulate contamination. The synergy of space radiation (particles, UV) and thermal cycling ages the material and induces mechanical stress, causing creation of brittle surfaces, cracks and delamination. These phenomena cause serious damage to exposed surfaces, changing the surfaces thermo-optical properties, and may induce the generation of space debris. In particular, experimental results show the delamination of internal MLI layers and the severe degradation of the Velcros

Analyse des circuits integres par microscopie electronique en transmission : controle de qualite, evaluation de la fiabilite

SIGLECNRS T Bordereau / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Space environmental testing of novel candidate materials for multilayer insulation

International audienceMultilayer insulation forms the outer barrier of a satellite towards space. Polymer foils used in multilayer insulation have to withstand the space environment for mission durations often lasting well above 10 years. This paper outlines the space environmental test campaign performed to qualify novel and advanced polymer foils to reduce blanket mass and replace export-controlled materials. Complete multilayer insulation layups were irradiated; these were composed of thicker outermost layers of the reference material Kapton®, a white polyimide and an alternative, conductive black polyimide and up to seven thin internal, aluminized 6  μm or 3  μm polyethylene terephthalate and polyethylene naphthalate layers separated by nonwoven spacers. One sample set consisted of 25  μm polyether-ether-ketone foil and 6  μm internal vacuum-deposited-aluminum-coated polyether-ether-ketone layers. Materials were exposed to ultraviolet, electrons and protons simulating a 15-year geostationary orbit mission. Absorptance was measured at various stages in situ during the exposures, and emittance was measured ex situ at the beginning and end of the test. With tensile testing, exposure influence on foil mechanical properties was determined and compared with pristine and reference materials. Although the white polyimide was sensitive to ultraviolet and showed strong degradation after ultraviolet and proton exposure, degradation of all other materials was within expected limits and compatible to state-of-the-art foils

Influence des oxydes d'espacement et des LDDs sur la réponse à la dose ionisante pour des MOSFETs fonctionnant à températures cryogéniques

International audienceIn this work, the radiation responses of 0.25 μm bulk transistors irradiated up to 300 krad are discussed. The electricals characteristics shown are measured after irradiation at 95 K, 150 K, and 300 K. The transconductance improves significantly with total ionizing dose (TID) at low temperature and does not vary at room temperature. The impact of incomplete ionization of impurities introduced into the Lightly Doped Drain extensions is examined. Since the transconductance increase is more pronounced for the shortest transistors, positive charges trapped in spacer oxides are likely to constitute the source of this increase. The Technology Computer-Aided Design simulations help us to discuss the influence of charge build-up at the spacers' locations on the drain to source resistance. By the means of a resistivity analysis, the influence of LDD doping level and operating temperature on the TID response of devices is analyzed. Its potential evolution with technological integration is investigated

Cellules solaires en pérovskite soumises à une irradiation aux protons : de la surveillance in situ de l'IV à l'élucidation des causes profondes de la dégradation

International audienceIn recent years, the mixed halide Perovskite Solar Cells (PSCs) triggered huge amount of R&D activities, thanks to their excellent optoelectronic properties, fast progressing power conversion efficiencies and low cost potential. On top of that, with their high specific power & compatibility with flexible substrate, PSCs appear as a promising mid/long-term alternative photovoltaic technology for space applications. However, the harsh space environment requires particularly robust PV solutions, especially against electrons & protons irradiations; detailed evaluation and comprehension of ageing under irradiations are thus key steps on PSCs development path. In this paper, we focus on perovskite materials and subsequently solar cells proton radiation hardness, with a fluence up to 5 x 1014 protons/cm2 at 1 MeV. Optical, microstructural and electrical characterisations, both in-situ and ex-situ, are used to track the evolutions of 4 different perovskite stoichiometries under irradiation. To this end, single layers, sub-assemblies and full solar cells stack were exposed to protons flux. This systematic approach allowed us to highlight the differences in radiation hardness of PSCs constituting layers: the photo-active Cs0.05FA0.95Pb(I1-xBrx)3 materials exhibits outstanding radiation hardness under the tested conditions, while the PTAA Hole Transport Layer (HTL) appears as a weak contact layer driving cells performance degradation at high fluences.Ces dernières années, les cellules solaires à halogénures mixtes pérovskites (PSC) ont suscité un grand nombre d'activités de R&D, grâce à leurs excellentes propriétés optoélectroniques, à leurs rendements de conversion d'énergie qui progressent rapidement et à leur faible coût potentiel. En outre, grâce à leur puissance spécifique élevée et à leur compatibilité avec les substrats souples, les PSC apparaissent comme une technologie photovoltaïque alternative prometteuse à moyen/long terme pour les applications spatiales. Cependant, l'environnement hostile de l'espace exige des solutions photovoltaïques particulièrement robustes, notamment contre les irradiations d'électrons et de protons ; l'évaluation détaillée et la compréhension du vieillissement sous irradiation sont donc des étapes clés sur la voie du développement des PSC. Dans cet article, nous nous concentrons sur les matériaux pérovskites et, par conséquent, sur la résistance des cellules solaires aux rayonnements de protons, avec une fluence allant jusqu'à 5x1014 protons/cm² à 1 MeV. Des caractérisations optiques, microstructurales et électriques, à la fois in-situ et ex-situ, sont utilisées pour suivre l'évolution de 4 stœchiométries de pérovskite différentes sous irradiation. A cette fin, des couches uniques, des sous-ensembles et des piles de cellules solaires complètes ont été exposés à un flux de protons. Cette approche systématique nous a permis de mettre en évidence les différences de dureté aux radiations des PSCs constituant les couches : les matériaux photo-actifs Cs0.05FA0.95Pb(I1-xBrx)3 présentent une dureté aux radiations exceptionnelle dans les conditions testées, tandis que la couche de transport de trous PTAA (HTL) apparaît comme une couche de contact faible entraînant une dégradation des performances des cellules

Étude in-situ et ex-situ des irradiations de protons et d'électrons sur des cellules solaires en pérovskite

International audienceThe need for low cost photovoltaic solutions is becoming more and more important with the ongoing NewSpace revolution. In this context, alternative solar cell technologies are under the spotlight, in particular perovskites which can reach high specific power. In this study, we investigate the electron and proton radiation hardness of multi-cation mixed halide perovskite cells CsxFA1-xPb(IyBr1-y)3. The proton irradiations demonstrate an excellent radiation hardness of the perovskite material but also highlight the degradation of the HTL layer. And the in-situ IV measurements under vacuum following the electron irradiations reveals a self-healing phenomena.Le besoin de solutions photovoltaïques à faible coût devient de plus en plus important avec la révolution NewSpace en cours. Dans ce contexte, les technologies alternatives de cellules solaires sont sous les feux de la rampe, en particulier les pérovskites qui peuvent atteindre une puissance spécifique élevée. Dans cette étude, nous étudions la dureté aux rayonnements électroniques et protoniques des cellules pérovskites à halogénures mixtes multi-cations CsxFA1-xPb(IyBr1-y)3. Les irradiations aux protons démontrent une excellente résistance aux radiations du matériau pérovskite, mais mettent également en évidence la dégradation de la couche HTL. Les mesures in situ de l'IV sous vide après les irradiations aux électrons révèlent un phénomène d'auto-guérison

Étude in-situ et ex-situ des irradiations de protons et d'électrons sur des cellules solaires en pérovskite

Voir aussi https://hal.science/hal-04164730v1International audienceThe need for low cost photovoltaic solutions is becoming more and more important with the ongoing New Space revolution. In this context, alternative solar cell technologies are under the spotlight, in particular perovskites with the potential to become a cost-effective solution with high specific power. In this study, we investigate the electron and proton radiation hardness of multi-cation mixed halide perovskite cells Cs$_x$FA$_{1-x}$Pb(I$_y$Br$_{1-y}$)$_3$. With the proton irradiations tested here, we demonstrate an excellent radiation hardness of the perovskite absorber material but also highlights the degradation of the HTL layer within the device. The electron irradiations show no significant degradation and the in-situ IV measurements under vacuum reveals self-healing phenomena.Le besoin de solutions photovoltaïques à faible coût devient de plus en plus important avec la révolution du New Space en cours. Dans ce contexte, les technologies alternatives de cellules solaires sont sous les feux de la rampe, en particulier les pérovskites qui peuvent atteindre une puissance spécifique élevée. Dans cette étude, nous étudions la dureté aux rayonnements électroniques et protoniques des cellules pérovskites à halogénures mixtes multi-cations Cs$_x$FA$_{1-x}$Pb(I$_y$Br$_{1-y}$)$_3$. Les irradiations aux protons démontrent une excellente résistance aux radiations du matériau pérovskite mais mettent également en évidence la dégradation de la couche HTL à l'intérieur du dispositif. Les irradiations aux électrons ne montrent pas de dégradation significative et les mesures in situ de l'IV sous vide après les irradiations aux électrons révèlent un phénomène d'auto-guérison.Pérovskite irradiation proton

Étude in-situ et ex-situ des irradiations de protons et d'électrons sur des cellules solaires en pérovskite

International audienceThe need for low cost photovoltaic solutions is becoming more and more important with the ongoing NewSpace revolution. In this context, alternative solar cell technologies are under the spotlight, in particular perovskites which can reach high specific power. In this study, we investigate the electron and proton radiation hardness of multi-cation mixed halide perovskite cells CsxFA1-xPb(IyBr1-y)3. The proton irradiations demonstrate an excellent radiation hardness of the perovskite material but also highlight the degradation of the HTL layer. And the in-situ IV measurements under vacuum following the electron irradiations reveals a self-healing phenomena.Le besoin de solutions photovoltaïques à faible coût devient de plus en plus important avec la révolution NewSpace en cours. Dans ce contexte, les technologies alternatives de cellules solaires sont sous les feux de la rampe, en particulier les pérovskites qui peuvent atteindre une puissance spécifique élevée. Dans cette étude, nous étudions la dureté aux rayonnements électroniques et protoniques des cellules pérovskites à halogénures mixtes multi-cations CsxFA1-xPb(IyBr1-y)3. Les irradiations aux protons démontrent une excellente résistance aux radiations du matériau pérovskite, mais mettent également en évidence la dégradation de la couche HTL. Les mesures in situ de l'IV sous vide après les irradiations aux électrons révèlent un phénomène d'auto-guérison

Simulation of Single and Multi-Node Collection: Impact on SEU Occurrence in Nanometric SRAM Cells

International audienc