Retour au site du LAAS-CNRS

Laboratoire d’analyse et d’architecture des systèmes
Choisir la langue : FR | EN

679documents trouvés

17689
22/01/2019

Ionic Electrochemical Actuators

A.MAZIZ, A.SIMAITE, C.BERGAUD

MEMS

Ouvrage (contribution) : Polymerized Ionic Liquids, Royal Society of Chemistry, N°ISBN 978-1-78262-960-3, Janvier 2019, Chapter 16, pp.456-488 , N° 17689

Lien : https://hal.laas.fr/hal-01976995

Diffusable

Plus d'informations

Abstract

Ionic electroactive polymer (iEAP) actuators with ionic liquid (IL) electrolytes are distinguished by their ability to operate in ambient air with an enhanced lifetime. This chapter reports the developments in iEAP actuator technologies for several applications, with a particular focus on the use of conducting polymers (CPs). CPs have attracted attention because of their promising electronic, optical and electromechanical properties. These smart materials are characterized by their possible dimensional changes due to the migration or diffusion of ions upon electrochemical oxidation or reduction processes. In an adequate ionic conducting medium, CPs can be used as the active component in actuators and lead to interesting potential applications, including soft robotics, prosthetic devices, microsystems and medical devices. This chapter starts with an overview of existing iEAP actuators. CP actuation mechanisms and configurations are explained in detail, and existing and potential applications are discussed, emphasizing the benefits of using ionic liquids (high ionic conductivity, non-volatility, larger electrochemical window and biocompatibility). Finally, to conclude, the future developments and challenges in this area are discussed.

146155
18463
05/12/2018

Comprehensive optical losses investigation of VLSI Silicon optomechanical ring resonator sensors

L.SCHWAB, P.ALLAIN, L.BANNIARD, A.FAFIN, M.GELY, O.LEMONNIER, P.GROSSE, M.HERMOUET, S.HENTZ, I.FAVERO, B.LEGRAND, G.JOURDAN

MEMS, MPQ, CEA-LETI

Manifestation avec acte : International Electron Devices Meeting ( IEDM ) 2018 du 01 décembre au 05 décembre 2018, San Francisco (USA), Décembre 2018 , N° 18463

Lien : https://hal.laas.fr/hal-01963015

Diffusable

Plus d'informations

Abstract

Cavity optomechanics devices are leading edge candidates for a new generation of sensors both in the quantum and classical realms. Several single devices have been demonstrated in numerous labs, however large-scale integration capability necessary for industrial deployment is still an issue. In this paper, we present very-large-scale integrated (VLSI) optomechanical sensors fabricated from standard 200 mm Silicon-On-Insulator (SOI) wafers. Optical properties over a statistically significant sample size have been systematically investigated and show an excellent modeling to experiment agreement, a coupling parameter dispersion of 7% and a manufacturing yield larger than 98%. Controlled versatile sensors, such as these, could easily be embedded in any chip where mass or force sensing is needed.

145933
18560
01/12/2018

Insight of surface treatments for CMOS compatibility of InAs nanowires

D.DHUNGANA, A.HEMERYCK, N.SARTORI, P.F.FAZZINI, F.CRISTIANO, S.PLISSARD

MPN, M3, EXT, LPCNO

Revue Scientifique : Nano Research, Décembre 2018 , N° 18560

Lien : https://hal.laas.fr/hal-02017661

Diffusable

Plus d'informations

Abstract

A CMOS compatible process is presented in order to grow self-catalyzed InAs nanowires on silicon by molecular beam epitaxy. The crucial step of this process is a new in-situ surface preparation under hydrogen (gas or plasma) during the substrate degassing combined with an in-situ arsenic annealing prior to growth. Morphological and structural characterizations of the InAs nanowires are presented and growth mechanisms are discussed in detail. The major influence of surface termination is exposed both experimentally and theoretically using statistics on ensemble of nanowires and density functional theory (DFT) calculations. The differences observed between Molecular Beam Epitaxy (MBE) and Metal Organic Vapor Phase Epitaxy (MOVPE) growth of InAs nanowires can be explained by these different surfaces terminations. The transition between a vapor solid (VS) and a vapor liquid solid (VLS) growth mechanism is presented. Optimized growth conditions lead to very high aspect ratio nanowires (up to 50 nm in diameter and 3 micron in length) without passing the 410 °C thermal limit, which makes the whole process CMOS compatible. Overall, our results suggest a new method for surface preparation and a possible tuning of the growth mechanism using different surface terminations.

146573
18342
09/11/2018

Optomechanical Resonating Probe for Very High Speed Sensing of Atomic Forces

P.ALLAIN, L.SCHWAB, C.MISNER, M.GELY, E.MAIRIAUX, M.HERMOUET, B.WALTER, G.LEO, S.HENTZ, M.FAUCHER, G.JOURDAN, B.LEGRAND, I.FAVERO

MPQ, MEMS, IEMN, CEA-LETI, VMICRO Sas, Paris Diderot, IEMN Villeneuve

Rapport LAAS N°18342, Novembre 2018, 14p.

Lien : https://hal.laas.fr/hal-01908683

Diffusable

Plus d'informations

Abstract

Atomic force spectroscopy and microscopy (AFM) are invaluable tools to characterize nanostructures and biological systems . Most experiments, including state -­‐ of -­‐ the -­‐ art images of molecular bonds, are achieved by driving probe s at their mechanical resonance . This resonance reaches the MHz for the fastest AFM micro -­‐ cantilevers , with typical motion amplitude of a few nanomet re s . Next -­‐ generation investigation s of molecular scale dynamics, including faster force imaging and high er -­‐ resolution spectroscopy of dissipative interactions, require more bandwidth and vibration amplitude s below in t er atomic distance , for non -­‐ pertu r bative short -­‐ range tip -­‐ matter interactions . Probe frequency is a key parameter to improve bandwidth while reducing Brownian motion , allowing large signal -­‐ to -­‐ noise for exquisite resolution . O ptomechanical resonators reach motion detection at 10 -­‐ 18 m.Hz -­‐ 1/2 , while coupling light to bulk vibration modes whose frequencies largely surpass those of cantilevers . Here we introduce a n optically operated resonating optomechanical atomic force probe of frequency 2 decades above the fastest functional AFM cantilevers while Brownian motion is 4 orders below. B ased on a Silicon -­‐ On -­‐ Insulator technology, the probe demonstrates high -­‐ speed sensing of contact and non -­‐ contact interactions with sub -­‐ picomet r e driven motion, breaking open current locks for faster and finer atomic force spectroscopy .

145036
18430
06/11/2018

Isolement de biomarqueurs cellulaires et moléculaires en oncologie et développement d'approches bas-coût pour leur analyse en routine clinique

A.ESTEVE

ELIA

Doctorat : INSA de Toulouse, 6 Novembre 2018, Président: C.VIEU, Rapporteurs: T.LEBLOIS, F.BERGER, Examinateurs: A.PRADINES, P.SAINTIGNY, Directeurs de thèse: A.CERF , N° 18430

Diffusable

Plus d'informations

Résumé

Le cancer est une pathologie complexe, qui se décline en une multitude de sous-types, faisant de chaque patient atteint de cancer, un cas clinique unique. La médecine de précision ou médecine personnalisée a pour objectif de proposer au patient un traitement et un suivi thérapeutique adaptés aux caractéristiques biologiques de la tumeur qui l’affecte. L’analyse de certains facteurs immunologiques et du profil moléculaire de la tumeur sont couramment effectués sur des prélèvements tissulaires, ou biopsies solides, permettant aux cliniciens d’obtenir des informations sur les spécificités de la tumeur mais aussi sur le microenvironnement dans lequel elle se développe, pour choisir la thérapie la plus adaptée. Une approche médicale moins invasive appelée « biopsie liquide », suscitant de plus en plus d’intérêt au sein de la communauté scientifique, pourrait permettre d’obtenir des informations plus précises avec un échant! illonnage plus répété, à partir de biomarqueurs tumoraux ou issus de la tumeur circulant dans les fluides corporels. Ces biomarqueurs peuvent être de différentes natures, comme les cellules tumorales circulantes (CTCs), des cellules s’étant détachées de la tumeur pour rejoindre la circulation sanguine, l’ADN tumoral circulant (ADNtc), des fragments d’ADN libérés par la tumeur, ou les exosomes, des vésicules produites principalement par des cellules de la tumeur contenant des protéines et de l’ADN tumoral. La détection et l’analyse de ces biomarqueurs en routine clinique pourraient permettre le suivi en temps réel de l’efficacité des thérapies pour améliorer la prise en charge des patients, un pas de plus vers une médecine personnalisée. L’objectif de ce travail a été de développer de nouveaux micro-dispositifs pour la capture de cellules tumorales circulantes, ainsi que d’explorer un ensemble de techniques pour faciliter leur analyse a! ux niveaux cellulaire et moléculaire, en vue d’une utilisat! ion en routine clinique. Dans un premier temps, une approche innovante de capture des CTCs in vivo, exploitant leurs propriétés physiques spécifiques a été envisagée. La capture directement au sein de la circulation sanguine du patient, pourrait permettre de sonder un volume plus important et ainsi isoler un plus grand nombre de CTCs en conditions natives ainsi que d’obtenir une meilleure représentation de leur diversité. Des techniques visant à simplifier et diminuer le coût des analyses, ont ensuite été explorées de manière à rendre la biopsie liquide utilisable en routine clinique. Parmi ces techniques, l’assemblage capillaire dirigé, utilisé pour étirer et immobiliser de façon organisée des biomolécules 1D, a également permis d’isoler des fragments d’ADN libre circulant, à partir d’échantillons de sang complet non traités. Dans le contexte de la médecine de précision, une autre approche peut être de tester les effets d’un certain ! nombre de médicaments sur les CTCs provenant du patient-même, de manière à personnaliser son traitement. Pour cela, après capture des CTCs, il peut être intéressant de les cultiver in vitro. C’est dans cette perspective que nous avons intégré les micro-dispositifs de capture à des plateformes qui permettraient la culture des cellules capturées directement in situ. Pour recréer un environnement propice à leur prolifération, la structuration de matériaux biocompatibles à base de nano-cristaux de cellulose favorisant l’adhésion des cellules a été investiguée. Nos résultats fournissent un ensemble de technologies qui pourraient contribuer à la démocratisation du concept de biopsie liquide en routine clinique.

Mots-Clés / Keywords
Microfabrication; Biomarqueurs; Oncologie;

145755
18468
01/11/2018

Microfluidics for minute DNA sample analysis: open challenges for genetic testing of cell-free circulating DNA in blood plasma

R.MALBEC, J.CACHEUX, P.CORDELIER, T.LEICHLE, P.JOSEPH, A.BANCAUD

MICA, MEMS, CRCT-INSERM, MILE

Revue Scientifique : Micro and Nano Engineering, Vol.1, pp.25-32, Novembre 2018 , N° 18468

Lien : https://hal.archives-ouvertes.fr/hal-01997320

Diffusable

Plus d'informations

Abstract

Genetic testing based on the analysis of circulating cell-free DNA (cfDNA) in body fluids, especially blood plasma, is raising interest for the management and follow-up of many diseases, including cancer. Because the concentration of cfDNA is low and its composition mostly degraded, this material can only be assayed with the most sensitive nucleic acid processing technologies. cfDNA analysis therefore constitutes a model target and a driving force for innovation in microfluidic biotechnologies. Here, we overview the main physico-chemical characteristics of cfDNA, and provide a critical review on the different methods for its processing out of blood samples. Then, we describe recent microfluidic developments for high sensitivity DNA analysis, evaluate their practical relevance for cfDNA analysis, and identify a few challenges for technologists in the near future.

145977
18465
01/11/2018

Nanofluidic fluorescence microscopy with integrated concentration gradient generation for one-shot parallel kinetic assays

P.TEERAPANICH, M.PUGNIERE, C.HENRIQUET, Y.L.LIN, A.NAILLON, P.JOSEPH, C.F.CHOU , T.LEICHLE

MEMS, IRCM, Academia Sinica, MILE

Revue Scientifique : Sensors and Actuators B: Chemical, N°274, pp.338-342, Novembre 2018 , N° 18465

Lien : https://hal.archives-ouvertes.fr/hal-01964831

Diffusable

Plus d'informations

Abstract

We report a simple and cost-effective nanofluidic fluorescence microscopy platform with parallel kinetic assay capability for the determination of kinetic parameters in a single run. An on-chip microfluidic concentration diluter, or gradient generator, was integrated to a biofunctionalized nanofluidic chip, enabling simultaneous interrogation of multiple biomolecular interactions with a full titration series of analyte in a single experiment. We demonstrate that since the association and dissociation phases are induced by the on-chip gradient generator and a reverse buffer flow operation, complete kinetic sensorgrams for IgG/anti-IgG interactions can be achieved within 20 min on a single device, which is at least 10 times faster than traditional kinetic techniques. This method could contribute to low-cost, rapid and high-throughput drug-screening and clinical diagnostics.

145965
18540
01/11/2018

Study of aluminium oxide thin films deposited by plasma-enhanced atomic layer deposition from tri-methyl-aluminium and dioxygen precursors: Investigation of interfacial and structural properties

A.LALE, E.SCHEID, F.CRISTIANO, L.DATAS, B.REIG, J.LAUNAY, P.TEMPLE BOYER

MICA, MPN, CIRIMAT, TEAM

Revue Scientifique : Thin Solid Films, Vol.666, pp.20-27, Novembre 2018 , N° 18540

Lien : https://hal.archives-ouvertes.fr/hal-01921105

Diffusable

Plus d'informations

Abstract

Aluminium oxide (Al 2 O 3) films were deposited on silicon substrates using plasma-enhanced atomic layer de-position (PE-ALD) technique with tri-methyl-aluminium TMA (Al(CH 3) 3) and dioxygen (O 2) as precursors. PE-ALD experiments were performed in order to (i) investigate the interfacial properties between the silicon sub-strate and the alumina layer, and (ii) understand the impact of growth and crystallization phenomena on the Al 2 O 3 films properties (structural, optical, mechanical, dielectric and etch). The formation of oxide-based transition layers, either silicon oxide SiO 2 and/or aluminosilicate Al x Si y O, was evidenced for the TMA/O 2 PE-ALD process. Based on these results, it appears that no substrate-enhanced growth occurs at the early stages of the growth process, as assumed in previous reports. Thus, constant growth rate (0.08 nm per cycle) and re-fractive index (1.64 at a 450 nm wavelength) were obtained for the Al 2 O 3 layer deposited at 300 °C. Finally, thermal annealing experiments were performed on these films, evidencing the influences of atomic structural rearrangement and crystallization on the Al 2 O 3 film main characteristics: interface steepness, atomic structure, refractive index, residual stress, dielectric constant and etch rate.

146397
18228
01/11/2018

Fano-Resonances in High Index Dielectric Nanowires for Directional Scattering

P.WIECHA, A.CUCHE, H.KALLEL, G.COLAS DES FRANCS, A.LECESTRE, G.LARRIEU, V.LARREY, F.FOURNEL, T.BARON, A.ARBOUET, V.PAILLARD

CEMES/CNRS, LICB, TEAM, MPN, CEA-LETI, LTM

Ouvrage (contribution) : Fano Resonances in Optics and Microwaves, Springer, N°ISBN 978-3-319-99730-8, Vol.310, Novembre 2018, Chapter 12, pp.283-2 , N° 18228

Lien : https://hal.archives-ouvertes.fr/hal-01850259

Diffusable

Plus d'informations

Abstract

High refractive index dielectric nanostructures provide original optical properties thanks to the occurrence of size- and shape-dependent optical resonance modes. These modes commonly present a spectral overlap of broad, low-order modes (\textit{e.g}. dipolar modes) and much narrower, higher-order modes. The latter are usually characterized by a rapidly varying frequency-dependent phase, which - in superposition with the lower order mode of approximately constant phase - leads to typical spectral features known as Fano resonances. Interestingly, such Fano resonances occur in dielectric nanostructures of the simplest shapes. In spheroidal nanoparticles, interference between broad magnetic dipole and narrower electric dipole modes can be observed. In high aspect-ratio structures like nanowires, either the electric or the magnetic dipolar mode (depending on the illumination conditions) interferes with higher order multipole contributions of the same nature (electric or magnetic). Using the analytical Mie theory, we analyze the occurrence of Fano resonances in high-index dielectric nanowires and discuss their consequences like unidirectional scattering. By means of numerical simulations, we furthermore study the impact on those Fano resonances of the shape of the nanowire cross-sections as well as the coupling of two parallel nanowires. The presented results show that all-dielectric nanostructures, even of simple shapes, provide a reliable low-loss alternative to plasmonic nanoantennas.

144273
18506
01/11/2018

Tuning the properties of silk fibroin biomaterial via chemical cross-linking

A.MAZIZ, O.LEPRETTE, L.BOYER, MC.BLATCHE, C.BERGAUD

MEMS, I2C

Revue Scientifique : Biomedical Physics & Engineering Express, Vol.4, N°6, 065012p., Novembre 2018 , N° 18506

Lien : https://hal.laas.fr/hal-01974627

Diffusable

Plus d'informations

Abstract

Protein-based biomaterials with innovative and controlled performance are being sought due to their unique characteristics for use in biomedical fields such as neural implants, drug delivery systems, cell-based therapies and soft tissue engineering. Here, we present a versatile approach for the synthesis of photo-crosslinkable fibroin silk biomaterial with highly tunable mechanical, chemical and biodegradation properties. Unlike the crystalline rich silk fibroin reported previously, the covalently cross-linked fibroin protein photoresist (FPP) via controlled light-induced radical grafting, allows generating a new amorphous biomaterial with tunable properties. It appears that the use of photo-reactive acrylate groups to cross-link FPP induces plasticity that can be tuned by changing the photoinitiator concentration of the film. Tensile strength measurements revealed that elasticity was higher for FPP UV-cross-linked materials with higher concentration of photoinitiator. FTIR and relative humidity measurements showed that hydrophilicity was higher for UV-cross-linked FPP. These materials display stiffness between 0.01–1.5 GPa and tensile strains up to 60%, covering a significant portion of the properties of native soft biomaterials. Besides, in vitro proteolytic degradation of the photocrosslinked FPP films demonstrate a tunable degradation rate over a period ranging from hours to weeks. Those biomaterials have been successfully micropatterned by photolithography techniques across several orders of magnitude (μm to cm) and a systematic study of direct patterning of the fibroin protein to form high fidelity and high-resolution structures has been reported. It was also shown that the fabricated protein features are well suited to cell adhesion. The development of protein-based material with controlled and tunable elasticity that can be easily photo-patterned into centimeter, micrometer and nanometer components will allow a wide range of applications in biomedical fields requesting a natural functional tissue.

146131
Les informations recueillies font l’objet d’un traitement informatique destiné à des statistiques d'utilisation du formulaire de recherche dans la base de données des publications scientifiques. Les destinataires des données sont : le service de documentation du LAAS.Conformément à la loi « informatique et libertés » du 6 janvier 1978 modifiée en 2004, vous bénéficiez d’un droit d’accès et de rectification aux informations qui vous concernent, que vous pouvez exercer en vous adressant à
Pour recevoir une copie des documents, contacter doc@laas.fr en mentionnant le n° de rapport LAAS et votre adresse postale. Signalez tout problème de dysfonctionnement à sysadmin@laas.fr. http://www.laas.fr/pulman/pulman-isens/web/app.php/