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Electronics, Electronique, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Méthodes de nanofabrication, Methods of nanofabrication, Formation de nanomotifs, Nanoscale pattern formation, Traitements de surface, Surface treatments, Sciences appliquees, Applied sciences, Electronique, Electronics, Electronique des semiconducteurs. Microélectronique. Optoélectronique. Dispositifs à l'état solide, Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices, Dispositifs à ondes acoustiques, piézoélectriques, piézorésistifs, Acoustic wave devices, piezoelectric and piezoresistive devices, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Surface treatment, Composé III-VI, III-VI compound, Compuesto III-VI, Alumine, Alumina, Alúmina, Tonerde, Aluminium, Aluminio, Angle contact, Contact angle, Angulo contacto, Kontaktwinkel, Anodisation, Anodizing, Anodización, Elektrolytisches Oxidieren, Courant intense, High strength current, Corriente intensa, Diminution coût, Cost lowering, Reducción costes, Kostensenkung, Dispositif entraînement, Driving device, Dispositivo arrastre, Durcissement, Hardening, Endurecimiento, Haerten, Electrolyte acide, Acid electrolyte, Electrólito ácido, Evaluation performance, Performance evaluation, Evaluación prestación, Formation nanomotif, Nanopatterning, Formacíon nanomotivo, Gyroscope, Giroscopio, Microscopie électronique balayage, Scanning electron microscopy, Microscopía electrónica barrido, Rasterelektronenmikroskopie, Nanocomposite, Nanocompuesto, Nanofil, Nanowires, Nanostructure, Nanoestructura, Précision élevée, High precision, Precisión elevada, Rotor, Surface rugueuse, Rough surface, Superficie rugosa, Rauhe Oberflaeche, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Traitement(durcissement), Curing, Vitesse déplacement, Speed, Velocidad desplazamiento, Geschwindigkeit, 0707D, 8107B, 8107V, 8116R, Al2O3, Matériau nanostructuré, Nanostructured material, Drag reduction, Liquid-floated rotor gyroscope, Nanostructured, and Oleophobic

Liquid-floated rotor gyroscopes can provide high accuracy at small volume and low cost. In rotor gyroscopes, the rotating speed of rotor can significantly affect the detection accuracy. This work presents a new kind of liquid-floated rotor gyroscope using super-oleophobic surface processing, which can improve the performance of driving system. In this work, an unconventional anodization in oxalic-acid electrolyte under high current was employed to fabricate diverse nanostructured alumina surfaces. The top-view SEM image shows the nanowire pyramid structure on the surface of processed sample. Modification of the rough surfaces was achieved by dipping substrates in 0.5 wt% 1H,1H,2H,2H-perfluoro-octadecyltrichlorosilane-in-hexane and then curing then at 120 °C for 1 h. The maximum contact angle (CA) of the aluminum rotor with nanowire pyramid structure was measured to be 156° in average. The oleophobicity of the rotor surface was used to reduce the resistance in the floating liquid. The test results show that, under the normal working state, the rotating speed of super-oleophobic rotor can be reached up to 3200 rpm. While a similar system without the micro-nano composite structure can only reach 2860 rpm. Thus, the nanostructured super-oleophobic alumina surface processing can greatly increase the rotating speed, thereby improving the performance of the gyro system.

Electronics, Electronique, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Propriétés et matériaux diélectriques, piézoélectriques et ferroélectriques, Dielectrics, piezoelectrics, and ferroelectrics and their properties, Propriétés diélectriques des solides et des liquides, Dielectric properties of solids and liquids, Permittivité (fonction diélectrique), Permittivity (dielectric function), Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Nanomatériaux et nanostructures : fabrication et caractèrisation, Nanoscale materials and structures: fabrication and characterization, Fils quantiques, Quantum wires, Traitements de surface, Surface treatments, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Surface treatment, Acrylique acide polymère, Acrylic acid polymer, Acrílico ácido polímero, Attaque chimique, Chemical etching, Ataque químico, Chemisches Aetzen, Caractéristique électrique, Electrical characteristic, Característica eléctrica, Elektrische Groesse, Centre accepteur, Acceptor center, Centro aceptor, Conduction limitée charge espace, Space-charge-limited conduction, Conductivité électrique, Electrical conductivity, Constante diélectrique, Permittivity, Coprécipitation, Coprecipitation, Dépôt par oxydoréduction, Electroless deposition, Eau, Water, Hydrophilie, Hydrophily, Hidrofilia, Loi Ohm, Ohm law, Matériau composite, Composite materials, Nanofil, Nanowires, Nanoparticule, Nanoparticles, Oxyde de titane, Titanium oxide, Titanio óxido, Titanoxid, Passivation, Phénomène transport, Transport processes, Piège, Traps, Propriété diélectrique, Dielectric properties, Propriété transport, Transport properties, Propiedad transporte, Propriété électrique, Electrical properties, Réseau(arrangement), Arrays, Semiconducteur type n, n type semiconductor, Semiconducteur type p, p type semiconductor, Silicium, Silicon, Tension polarisation, Bias voltage, Voltage polarización, Traitement surface, Surface treatments, 8107V, TiO2, Composite devices, Silicon nanowires, and Space charge limited current

We have presented the composite device including silicon nanowires (SiNWs), Polyacrylic acid (PAA) and Titanium dioxide nanoparticles (TiO2 NPs). SiNWs and TiO2 NPs were synthesized by metal assisted electroless chemical etching (MACE) and co-precipitation method respectively. Solution containing PAA and TiO2 NPs in DI water was spun on already grown vertical SiNW arrays. We have investigated the transport and dielectric properties of p-type SiNWs/PAA/TiO2 NPs (p-SPT) and n-type SiNWs/PAA/TiO2 NPs (n-SPT) composite devices. Presence of PAA/TiO2 NPs on the surface of SiNWs have increased electrical current in p-SPT device than that of n-SPT device. Ohmic like conduction was dominant at lower bias voltages followed by space charge limited current (SCLC) with traps at intermediate voltages. The calculated values of trap densities (Ht) were 7.73 × 1011 cm-3 and 5.34 × 1011 cm-3 for p-SPT device and n-SPT device respectively. Similarly p-SPT device shows higher real part of dielectric constant (ε') and AC conductivity (σac) ~15 times and ∼85 times respectively than that of n-SPT device. Increment in electrical and dielectric properties can be attributed to the presence of hydrophilic materials (PAA/TiO2 NPs) which may results in enhancement of acceptor like states.

Electronics, Electronique, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Nanomatériaux et nanostructures : fabrication et caractèrisation, Nanoscale materials and structures: fabrication and characterization, Nanotubes, Sciences appliquees, Applied sciences, Electronique, Electronics, Appareillage électronique et fabrication. Composants passifs, circuits imprimés, connectique, Electronic equipment and fabrication. Passive components, printed wiring boards, connectics, Electronique des semiconducteurs. Microélectronique. Optoélectronique. Dispositifs à l'état solide, Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices, Circuits intégrés, Integrated circuits, Conception. Technologies. Analyse fonctionnement. Essais, Design. Technologies. Operation analysis. Testing, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Capteur humidité, Moisture sensor, Sensor humedad, Feuchteaufnehmer, Capteur mesure, Measurement sensor, Captador medida, Messwertaufnehmer, Circuit intégré CMOS, CMOS integrated circuits, Circuit intégré, Integrated circuit, Circuito integrado, Integrierte Schaltung, Compatibilité, Compatibility, Compatibilidad, Kompatibilitaet, Configuration interdigitale, Interdigital configuration, Configuración interdigital, Configuration électrode, Electrode configuration, Configuración electrodo, Elektrodenkonfiguration, Couche mince, Thin film, Capa fina, Duennschicht, Critère performance, Performance requirement, Criterio resultado, Dispositif couche mince, Thin film device, Dispositivo capa delgada, Désorption, Desorption, Desorción, Haute performance, High performance, Alto rendimiento, Humidité, Humidity, Humedad, Feuchtigkeit, Hystérésis, Hysteresis, Histéresis, Hysterese, Interconnexion, Interconnection, Interconexión, Matériau revêtu, Coated material, Material revestido, Beschichteter Werkstoff, Microcapteur, Microsensor, Microcaptador, Miniaturisation, Miniaturization, Miniaturización, Miniaturisierung, Nanotube carbone, Carbon nanotubes, Nanotube multifeuillet, Multiwalled nanotube, Nanotubo pared múltiple, Norme, Standards, Norma, Norm, Oxyde de silicium, Silicon oxides, Polycristal, Polycrystal, Policristal, Polykristall, Revêtement, Coatings, Revestimiento, Ueberzug, Réseau (arrangement), Array, Red, Résistance électrique, Resistor, Resistencia eléctrica(componente), Sensibilité élevée, High sensitivity, Alta sensibilidad, Silicium polycristallin, Polysilicon, Silicio policristal, Technologie MOS complémentaire, Complementary MOS technology, Tecnología MOS complementario, Traitement thermique, Heat treatment, Tratamiento térmico, Waermebehandlung, 0707D, 0707V, 8107D, SiO2, Heating, Integration, Micro humidity sensor, Multi walled carbon nanotubes (MWCNTs), and Single chip

Miniaturization, integration and high performance are key requirements for the present humidity sensor development. One kind of single chip integrated MWCNTs thin film humidity sensor based on standard CMOS IC process was proposed in this paper. The sensor was designed and realized with MWCNTs/SiO2 thin film coated on exposed interdigital electrodes on chip, which was achieved by arrange PADs (bond pad opening) array on the top layer of layout by 0.5 μm DMDP 18 V process, at maximum exposure of the interdigital patterned metal2 electrodes. The sensor was surrounded by the heating cells formed by paralleled polysilicon resistors, which can accelerate desorption of condensed vapors and thus lower the humidity hysteresis, and provide good long time stability at high humidity environments. As the film was fabricated onto the electrodes in post process, it has great IC compatibility. The sensor has high sensitivity of 270% at 200 kHz and 120% at 50 kHz under sine source signal, and a fast response and recovery of 5 s and 7 s, respectively. It was found that nano SiO2 dispersed in film and middle frequency AC source on sensor can both reduce fluctuation of electron waves, and further lower the sensor's inherent noise. Besides, given the 30 μm interdigital finger gap, sensors with MWCNTs of 4-6 μm length has apparently lower current noise than those with 1-2 μm tubes under 4 kHz source signal. The chip is simple and compact, and low cost, and has good long time endurance in high humidity environments.

Electronics, Electronique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Méthodes de dépôt de films et de revêtements; croissance de films et épitaxie, Methods of deposition of films and coatings; film growth and epitaxy, Techniques de revêtement par pulvérisation, Spray coating techniques, Sciences appliquees, Applied sciences, Electronique, Electronics, Electronique des semiconducteurs. Microélectronique. Optoélectronique. Dispositifs à l'état solide, Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices, Dispositifs optoélectroniques, Optoelectronic devices, Energie, Energy, Energie naturelle, Natural energy, Energie solaire, Solar energy, Conversion photovoltaïque, Photovoltaic conversion, Cellules solaires. Cellules photoélectrochimiques, Solar cells. Photoelectrochemical cells, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Absorbeur, Absorber, Absorbente, Absorption 2 photons, Two photon absorption, Absorción 2 fotones, Assemblage circuit intégré, Integrated circuit bonding, Cellule solaire, Solar cell, Célula solar, Chalcopyrite, Calcopirita, Chalkopyrit, Couche mince, Thin film, Capa fina, Duennschicht, Couche tampon, Buffer layer, Capa tampón, Diffraction RX, X ray diffraction, Difracción RX, Roentgenbeugung, Dépôt projection, Spray coating, Depósito proyección, Spritzbeschichten, Effet température, Temperature effect, Efecto temperatura, Temperatureinfluss, Gain, Ganancia, Indium, Indio, Matériau absorbant, Absorbent material, Material absorbente, Matériau cristallin, Crystalline material, Material cristalino, Recuit mise en solution, Solution heat treatment, Recocido disolución, Loesungsgluehen, Relation ordre, Ordering, Relación orden, Site cristallographique, Crystallographic site, Sitio cristalográfico, Solution aqueuse, Aqueous solution, Solución acuosa, Waesserige Loesung, Spectre Raman, Raman spectrum, Espectro Raman, Spectrométrie Raman, Raman spectrometry, Espectrometría Raman, Spectrométrie dispersive, Dispersive spectrometry, Espectrometría dispersiva, Stoechiométrie, Stoichiometry, Estequiométría, Stoechiometrie, Sulfure d'indium, Indium sulfide, Indio sulfuro, Indiumsulfid, Technologie CSP, Chip scale packaging, Température substrat, Substrat temperature, Temperatura substrato, Température superficielle, Surface temperature, Temperatura superficial, Oberflaechentemperatur, Thiourée, Thiourea, Tiourea, 7830N, 8460J, Cellule solaire à bande intermédiaire, Intermediate band solar cell, In2S3, Pyrolyse par projection, Spray pyrolysis, Chemical spray pyrolysis, EDX, Raman spectroscopy, and XRD

Indium sulfide (In2S3) thin films are of interest as buffer layers in chalcopyrite absorber based solar cells; and as media providing two-photon absorption for intermediate-band solar cells. We investigated the suitability of chemical spray pyrolysis (CSP) for growing In2S3 thin films in a structural order where indium atoms are preferentially in the octahedral sites. We sprayed aqueous or alcoholic solutions of indium chloride (InCl3) and thiourea (SC(NH2)2) precursors onto a substrate with surface temperatures (Ts) of 205, 230, 275 and 320 °C. The as-deposited films grown from aqueous solutions were annealed in 5% H2S containing atmosphere at 500 °C. We used Raman spectroscopy, X-ray diffraction and Energy Dispersive X-ray spectroscopy to evaluate the effect of growth temperature and the effect of annealing on the film structure and stoichiometry. The use of alcoholic solvent instead of aqueous allows us to use much lower Ts while preserving the quality of the β-In2S3 films obtained. Similarly, films with increased stoichiometry and quality are present at a higher Ts; and when annealed. The annealing of the films grown at Ts of 205 °C results in a much higher gain of the crystal quality compared to the gain when annealing the films grown at Ts of 320 °C, although the quality remain higher when deposited at Ts of 320 °C. Simultaneously with the increase of the film quality, there is a sign of increased quality of the crystal ordering with indium in the octahedral sites. Such a crystal ordering favor the use of CSP deposited In2S3 films in the intermediate band solar cells.

Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Méthodes de dépôt de films et de revêtements; croissance de films et épitaxie, Methods of deposition of films and coatings; film growth and epitaxy, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Couche mince, Thin film, Capa fina, Duennschicht, Dépôt phase vapeur, Vapor deposition, Depósito fase vapor, Aufdampfen, Dépôt physique phase vapeur, Physical vapor deposition, Deposición física fase vapor, Physikalisches Aufdampfen, Dépôt projection, Spray coating, Depósito proyección, Spritzbeschichten, Membrane, Membrana, Membran, Perovskite, Perovskita, Plasma, Projection plasma, Plasma spraying, Proyección plasma, Plasmaspritzen, Projection à chaud, Hot spraying, Proyección en caliente, Spritzen, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, oxygen transport membrane, perovskite La1-xSrxCoyFe1-yO3-δ, plasma spray physical vapor deposition, porous metallic support, and thin films

Plasma spray physical vapor deposition (PS-PVD) is a very promising route to manufacture ceramic coatings, combining the efficiency of thermal spray processes and characteristic features of thin PVD coatings. Recently, this technique has been investigated to effectively deposit dense thin films of perovskites particularly with the composition of La0.58Sr0.4Co0.2Fe0.8O3-δ (LSCF) for application in gas separation membranes. Furthermore, asymmetric type of membranes with porous metallic supports has also attracted research attention due to the advantage of good mechanical properties suitable for use at high temperatures and high permeation rates. In this work, both approaches are combined to manufacture oxygen transport membranes made of gastight LSCF thin film by PS-PVD on porous NiCoCrAlY metallic supports. The deposition of homogenous dense thin film is challenged by the tendency of LSCF to decompose during thermal spray processes, irregular surface profile of the porous metallic substrate and crack and pore-formation in typical ceramic thermal spray coatings. Microstructure formation and coating build-up during PS-PVD as well as the annealing behavior at different temperatures of LSCF thin films were investigated. Finally, measurements of leak rates and oxygen permeation rates at elevated temperatures show promising results for the optimized membranes.

Electronics, Electronique, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure, proprietes mecaniques et thermiques, Condensed matter: structure, mechanical and thermal properties, Surfaces et interfaces; couches minces et trichites (structure et propriétés non électroniques), Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties), Interfaces solide-fluide, Solid-fluid interfaces, Mouillage, Wetting, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Traitements de surface, Surface treatments, Sciences appliquees, Applied sciences, Electronique, Electronics, Electronique des semiconducteurs. Microélectronique. Optoélectronique. Dispositifs à l'état solide, Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices, Fabrication microélectronique (technologie des matériaux et des surfaces), Microelectronic fabrication (materials and surfaces technology), Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Surface treatment, Mécanique fluide, Fluid mechanics, Mecánica flúido, Hydromechanik, Circuit intégré, Integrated circuit, Circuito integrado, Integrierte Schaltung, Dépôt plasma, Plasma deposition, Depósito plasma, Empilement, Stacking, Apilamiento, Encrassement, Fouling, Enmugrecimiento, Epaisseur, Thickness, Espesor, Dicke, Etherethercétone polymère, Polyetheretherketone, Eter éter cetona polímero, Fabrication microélectronique, Microelectronic fabrication, Fabricación microeléctrica, Formation motif, Patterning, Formacíon motivo, Gravure plasma, Plasma etching, Grabado plasma, Haute résolution, High resolution, Alta resolucion, Hydrocarbure fluoré, Fluorocarbon, Hidrocarburo fluorado, Hydrophilie, Hydrophily, Hidrofilia, Hydrophobicité, Hydrophobicity, Hidrofobicidad, Lithographie, Lithography, Litografía, Microfluidique, Microfluidics, Microfluidic, Mode empilement, Stacking sequence, Modo apilamiento, Mouillage, Wetting, Remojo, Méthacrylate de méthyle polymère, Methyl methacrylate polymer, Metacrilato de metilo polímero, Oxygène, Oxygen, Oxígeno, Sauerstoff, Photolithographie, Photolithography, Fotolitografía, Photorésist, Photoresist, Fotorresistencia, Propriété surface, Surface properties, Propiedad superficie, Oberflaecheneigenschaft, Réseau (arrangement), Array, Red, Résist, Resist, Resistencia, Silicium, Silicon, Silicio, Système sur puce, System on a chip, Sistema sobre pastilla, Technologie planaire, Planar technology, Tecnología planar, Traitement par plasma, Plasma assisted processing, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, 4785N, 8116N, 8116R, 8540H, Cancer cell patterning, Fibrosarcoma cancer cell line HT1080, Plasma nanotexturing, Selective cell attachment, cell repelling, Superhydrophobic, antifouling surfaces, and Thick resist patterning

We propose a planar technology for fabrication and surface modification of disposable, polymeric, microfluidic devices, and show applications in cell patterning. By planar technology we mean lithography directly on a polymeric plate followed by plasma etching of the plate. In this context, we developed lithographic processes directly on the polymeric substrate, employing easily strippable photoresists, for which stripping is performed without attacking the polymeric substrate. We then applied oxygen plasma etching to transfer the pattern and chemically modify the polymeric substrates, followed by optional fluorocarbon plasma deposition through stencil masks, producing microfluidic channels with desired geometrical and wetting characteristics. We tested various organic photoresists such as AZ 15nXT, AZ 9260, maP-1275, a silicon containing resist Ormocomp® on an organic strippable underlayer (LOR@), as well as metal masks in order achieve high resolution (1-4 μm), plasma etch resistance, and stripability for photoresists with thickness of ~5-20 μm (for details see Supporting information). We selected the Ormocomp® stack as the best candidate to define microfluidics with plasma etching onto PMMA, PEEK and COP substrates containing hydrophilic and superhydrophobic areas. We demonstrate significantly increased cell attachment on the plasma treated PMMA areas compared to untreated ones, and highly selective cell attachment (on-off) onto hydrophilic versus the superhydrophobic areas using a particular cell line. Such control of cell attachment and growth on plasma nanotextured surfaces can be applied to creation of microdevices aiming to cell patterning, cell isolation, as well as cell arrays.

Electronics, Electronique, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Traitements de surface, Surface treatments, Sciences appliquees, Applied sciences, Electrotechnique. Electroenergetique, Electrical engineering. Electrical power engineering, Matériaux, Materials, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Surface treatment, Propriétés mécaniques. Rhéologie. Mécanique de la rupture. Tribologie, Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology, Rupture, Fractures, Champ température, Temperature distribution, Contamination chimique, Chemical contamination, Contaminación química, Contrainte thermique, Thermal stresses, Couche autoassemblée, Self-assembled layers, Cycle thermique, Thermal cycle, Ciclo térmico, Temperaturverlauf, Dégradation, Degradation, Délaminage, Delamination, Endommagement, Damage, Etude comparative, Comparative study, Estudio comparativo, Vergleich, Fabrication microélectronique, Microelectronic fabrication, Fabricación microeléctrica, Formation motif, Patterning, Gonflement, Swelling, Matériau composite, Composite materials, Métallisation, Metallizing, Procédé voie sèche, Dry process, Procedimiento vía seca, Propriété surface, Surface properties, Répartition spatiale, Spatial distribution, Répétabilité, Repeatability, Repetibilidad, Siloxane(diméthyl) polymère, Dimethylsiloxane polymer, Siloxano(dimetil) polímero, Température ambiante, Ambient temperature, Traitement surface, Surface treatments, Traitement thermique, Heat treatments, Verre, Glass, 8105K, 8116D, 8116R, 8540H, 8540L, Dry peel-off process, Micro-heaters, Polydimethylsiloxane (PDMS), Self-assembled monolayer (SAM), and Surface modification

The present report describes a reliable fabrication method of micro-heaters embedded in polydimethylsiloxane (PDMS), and shows the characterization of the micro-heaters. Metallization of PDMS is achieved using a dry peel-off process which involves modifying the surface properties of the substrate and metal patterns through self-assembled monolayer (SAM) and manually peeling off the PDMS with embedded metal layers. Thus, micro-heaters embedded in PDMS can be fabricated by a simpler and easier way compared to a conventional method (e.g. patterning a conducting composite of PDMS using a razor blade). As a result, Au micro-heaters embedded in PDMS were successfully fabricated without any chemical swelling and contamination. Micro-heaters on a glass substrate were also fabricated for comparison with those embedded in PDMS. For heating up to 90 °C, the micro-heaters embedded in PDMS needed only ~90 mW compared to those fabricated on the glass substrate needed ~530 mW. Moreover, we could not observe any degradation of the micro-heaters by thermal stresses that confirmed by repeatability (10 thermal cycle with a range of 25-89 °C) and stability test (20 min at 90 °C). Micro-heaters took less than 60 s to reach the target temperature (90 °C) and spent less than 60 s to drop to room temperature. The spatial temperature distribution was not significantly varied with materials of the substrate (i.e. PDMS or glass).

Electronics, Electronique, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Propriétés optiques, spectroscopie et autres interactions de la matière condensée avec les particules et le rayonnement, Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation, Propriétés optiques des matériaux massifs et des couches minces, Optical properties of bulk materials and thin films, Constantes optiques: indice de réfraction; constante diélectrique complexe; coefficients d'absorption, de réflexion et de transmission; émissivité, Optical constants: refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Traitements de surface, Surface treatments, Sciences appliquees, Applied sciences, Electronique, Electronics, Electronique des semiconducteurs. Microélectronique. Optoélectronique. Dispositifs à l'état solide, Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices, Fabrication microélectronique (technologie des matériaux et des surfaces), Microelectronic fabrication (materials and surfaces technology), Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Surface treatment, Fabrication microélectronique, Microelectronic fabrication, Fabricación microeléctrica, Facteur réflexion, Reflectance, Coeficiente reflexión, Reflexionsfaktor, Force interatomique, Interatomic forces, Formation nanomotif, Nanopatterning, Formacíon nanomotivo, Gradient indice, Gradient index, Gradiente indicativo, Gravure ionique réactive, Reactive ion etching, Grabado iónico reactivo, Indice réfraction, Refraction index, Indice refracción, Brechungsindex, Lithographie sans masque, Maskless lithography, Litografía sin máscara, Matériau revêtu, Coated material, Material revestido, Beschichteter Werkstoff, Modèle milieu effectif, Effective medium model, Modelo medio efectivo, Moulage injection, Injection molding, Moldeo por inyección, Méthode matrice transfert, Transfer matrix method, Nanostructure, Nanoestructura, Nanotechnologie, Nanotechnology, Nanotecnología, Nickel, Niquel, Production masse, Mass production, Producción en masa, Massenproduktion, Propène polymère, Propylene polymer, Propeno polímero, Rayonnement visible, Visible radiation, Radiación visible, Lichtstrahlung, Revêtement, Coatings, Revestimiento, Ueberzug, Silicium, Silicon, Silicio, Spectre visible, Visible spectrum, Espectro visible, Temps exécution, Execution time, Tiempo ejecución, 7840R, 8116R, 8540H, Matériau nanostructuré, Nanostructured material, Antireflection, Black silicon, Injection moulding, Large area, Large volume production, and Nanofabrication

We present a method for injection moulding antireflective nanostructures on large areas, for high volume production. Nanostructured black silicon masters were fabricated by mask-less reactive ion etching, and electroplated with nickel. The nickel shim was antistiction coated and used in an injection moulding process, to fabricate the antireflective surfaces. The cycle-time was 35 s. The injection moulded structures had a height of 125 nm, and the visible spectrum reflectance of injection moulded black polypropylene surfaces was reduced from 4.5 ± 0.5% to 2.5 ± 0.5%. The gradient of the refractive index of the nanostructured surfaces was estimated from atomic force micrographs and the theoretical reflectance was calculated using the transfer matrix method and effective medium theory. The measured reflectance shows good agreement with the theory of graded index antireflective nanostructures.

Electronics, Electronique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Nanomatériaux et nanostructures : fabrication et caractèrisation, Nanoscale materials and structures: fabrication and characterization, Fils quantiques, Quantum wires, Méthodes de dépôt de films et de revêtements; croissance de films et épitaxie, Methods of deposition of films and coatings; film growth and epitaxy, Electrodépôt, Electrodeposition, electroplating, Sciences appliquees, Applied sciences, Electronique, Electronics, Electronique des semiconducteurs. Microélectronique. Optoélectronique. Dispositifs à l'état solide, Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices, Dispositifs à structure composée, Compound structure devices, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Composé II-VI, II-VI compound, Compuesto II-VI, Analyse structurale, Structural analysis, Análisis estructural, Anodisation, Anodizing, Bande interdite, Energy gap, Cristallite, Crystallites, Diffraction RX, XRD, Dépôt électrolytique, Electrodeposition, Exciton, Excitons, Fabrication microélectronique, Microelectronic fabrication, Fabricación microeléctrica, Hétérojonction, Heterojunctions, Hétérostructure, Heterostructures, Matériau conducteur, Conducting materials, Matériau revêtu, Coated material, Material revestido, Beschichteter Werkstoff, Matériau transparent, Transparent material, Material transparente, Mercure, Mercury, Microscopie électronique, Electron microscopy, Nanofil, Nanowires, Nanostructure, Nanostructures, Oxyde anodique, Anodic oxide, Oxyde d'aluminium, Aluminium oxide, Aluminio óxido, Aluminiumoxid, Recuit, Annealing, Revêtement, Coatings, Stoechiométrie, Stoichiometry, Structure blende, Blende structure, Estructura blenda, Structure wurtzite, Wurtzite structure, Estructura wurtzita, Sulfure de cadmium, Cadmium sulfide, Cadmio sulfuro, Cadmiumsulfid, Système photovoltaïque, Photovoltaic power systems, Tellurure de cadmium, Cadmium tellurides, Tellurure de mercure, Mercury tellurides, Verre, Glass, 8105K, 8107V, 8540H, CdS, Matériau nanostructuré, Nanostructured material, Méthode template, Template method, Anodic aluminum oxide, Galvanic contact deposition, Heterojunction, Mercury cadmium telluride, Multiple exciton generation, Nanowire, and Template

Single-material and heterojunction nanowires were fabricated from CdS and Hg(1-x)CdxTe (MCT) in anodic aluminum oxide templates grown on transparent conductive oxide coated glass substrates. Structural and compositional analyses were carried out by electron microscopy, elemental analysis and x-ray diffraction. CdS was deposited using potentiostatic electrodeposition, forming CdS nanowires with a 1:1 stoichiometry and wurtzite structure. MCT was also deposited using potentiostatic electrodeposition, forming MCT nanowires with a stoichiometry of Hg0.24Cd0.76Te and a zinc blende structure. Annealing of the electrodeposited MCT nanowires increased crystallite size from ~9nm to ∼23 nm in the (111) direction. Heterojunction nanowires were prepared by sequential electrodeposition of CdS and MCT with control over the length and diameter. These materials have a desirable band gap and geometry for multiple-exciton generation studies for nanostructured photovoltaics applications.

Electronics, Electronique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Méthodes de dépôt de films et de revêtements; croissance de films et épitaxie, Methods of deposition of films and coatings; film growth and epitaxy, Dépôt chimique en phase vapeur (incluant le cvd activé par plasma, mocvd, etc.), Chemical vapor deposition (including plasma-enhanced cvd, mocvd, etc.), Sciences appliquees, Applied sciences, Electronique, Electronics, Electronique des semiconducteurs. Microélectronique. Optoélectronique. Dispositifs à l'état solide, Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices, Dispositifs optoélectroniques, Optoelectronic devices, Energie, Energy, Energie naturelle, Natural energy, Energie solaire, Solar energy, Conversion photovoltaïque, Photovoltaic conversion, Cellules solaires. Cellules photoélectrochimiques, Solar cells. Photoelectrochemical cells, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Dispositif optoélectronique, Optoelectronic device, Dispositivo optoelectrónico, Article synthèse, Review, Artículo síntesis, Cellule solaire silicium, Silicon solar cells, Cellule solaire, Solar cell, Célula solar, Conversion énergie, Energy conversion, Conversión energética, Dépôt chimique phase vapeur, Chemical vapor deposition, Depósito químico fase vapor, Chemisches Aufdampfen, Fabrication microélectronique, Microelectronic fabrication, Fabricación microeléctrica, Facteur réflexion, Reflectance, Coeficiente reflexión, Reflexionsfaktor, Gravure, Engraving, Grabado, Indice réfraction, Refraction index, Indice refracción, Brechungsindex, Méthode PECVD, PECVD, Nanostructure, Nanoestructura, Nitrure de silicium, Silicon nitride, Silicio nitruro, Siliciumnitrid, Propriété surface, Surface properties, Propiedad superficie, Oberflaecheneigenschaft, Revêtement antiréfléchissant, Antireflection coating, Revestimiento antirreflexión, Silicium, Silicon, Silicio, Structure surface, Surface structure, Estructura superficie, Oberflaechenbeschaffenheit, Taux conversion, Conversion rate, Factor conversión, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, 4279W, 8115G, 8460J, 8540H, Black silicon, Nano, Reflectivity, and Refractive index

Anti-reflective (AR) coatings are a critical component of a commercially viable solar cell because by lowering reflection from the surface of the cell they enable more light to be absorbed and hence improve the power conversion efficiency of the cell. Silicon solar cells represent > 80% of present commercial cells and the most common AR coating is PECVD silicon nitride; however, recently, black silicon (b-Si) surfaces have been proposed as an alternative. Black silicon is a surface modification of silicon in which a nanoscale surface structure is formed through etching. Due to the continuous change of the refractive index of this structure surfaces with very low reflectivities are observed (~1%). This review summarizes the recent and substantial developments of black silicon for use in solar cells and discusses the advantages and disadvantages of the different methods of fabrication.

Electronics, Electronique, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure, proprietes mecaniques et thermiques, Condensed matter: structure, mechanical and thermal properties, Structure des liquides et des solides; cristallographie, Structure of solids and liquids; crystallography, Structure de solides cristallins particuliers, Structure of specific crystalline solids, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Méthodes de dépôt de films et de revêtements; croissance de films et épitaxie, Methods of deposition of films and coatings; film growth and epitaxy, Techniques de revêtement par pulvérisation, Spray coating techniques, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Physicochimie des réactions induites par rayonnements, particules et ultrasons, Physical chemistry of induced reactions (with radiations, particles and ultrasonics), Photochimie, Photochemistry, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Composé II-VI, II-VI compound, Compuesto II-VI, Activité catalytique, Catalyst activity, Actividad catalítica, Colorant basique, Basic dye, Colorante básico, Colorant triarylméthanique, Triarylmethane dye, Colorante triarilmetánico, Cristallisation, Crystallization, Cristalización, Kristallisation, Cristallite, Crystallites, Cristalita, Kristallit, Dopage, Doping, Dopen, Dépôt projection, Spray coating, Depósito proyección, Spritzbeschichten, Energie liaison, Binding energy, Energía enlace, Bindungsenergie, Matériau dopé, Doped materials, Matériau poreux, Porous material, Material poroso, Poroeser Werkstoff, Nanobâtonnet, Nanorod, Nanopalito, Oxyde de titane, Titanium oxide, Titanio óxido, Titanoxid, Oxyde de zinc, Zinc oxide, Zinc óxido, Zinkoxid, Photocatalyse, Photocatalysis, Fotocatálisis, Polymère, Polymer, Polímero, Porosité, Porosity, Porosidad, Porositaet, Pulvérisation, Spraying, Pulverización, Rayonnement UV, Ultraviolet radiation, Radiación ultravioleta, Ultraviolettstrahlen, Structure cristalline, Crystalline structure, Estructura cristalina, Kristallstruktur, Titane, Titanium, Titanio, Titan, Zinc, Zink, 8105L, 8105R, 8107D, 8245J, Pyrolyse par projection, Spray pyrolysis, TiO2, ZnO, Nanorods, TiO2-ZnO films, and UV-light

The crystallographic phase, surface features and photocatalytic properties in the reaction of decolorization of Malachite Green dye over TiO2 (0―100 mol%) doped ZnO films have been investigated. The films have been prepared by polymer modified spray pyrolysis. The crystallization degree and the size of the crystallites comprising the films have been found to be influenced by the TiO2 content in the spraying solution. The undoped ZnO film has little porosity. The titania dopant causes formation of hexagonal nanorods on the ZnO surface. The increase in TiO2 content results in enhancement of both size and crystallization degree of the nanorods. When the TiO2 content is increased (i) the Zn2p, O1s and Ti2p peaks are shifted to lower binding energies, (ii) the atomic ratio of OL/Zn is decreased and (iii) the amount of adsorbed hydroxyl (OH-) species is increased. All the TiO2 doped ZnO films manifested higher photocatalytic activity than that of the undoped ZnO and TiO2 samples. The films obtained from solutions with 50 mol% TiO2 showed the fastest decoloration of the dye.

Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Méthodes de dépôt de films et de revêtements; croissance de films et épitaxie, Methods of deposition of films and coatings; film growth and epitaxy, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Propriétés mécaniques. Rhéologie. Mécanique de la rupture. Tribologie, Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology, Etat surface, Surface conditions, Estado superficie, Oberflaechenzustand, Alliage base aluminium, Aluminium base alloys, Couche mince, Thin film, Capa fina, Duennschicht, Dureté, Hardness, Dureza, Haerte, Epaisseur, Thickness, Espesor, Dicke, Magnésium alliage, Magnesium alloy, Magnesio aleación, Magnesiumlegierung, Propriété mécanique, Mechanical properties, Propiedad mecánica, Rugosité, Roughness, Rugosidad, Rauhigkeit, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, and Amorphous

This work explored the effect of deposition pressure on the properties of the ternary AI―Mg―B thin films deposited on Si substrate at high deposition temperature (600°C) by magnetron sputtering system with one pure boron target and one Al/Mg co-target. The influences of the deposition pressure on the elemental contents, deposition rate, surface roughness, structure and mechanical properties were investigated by Electron microprobe analysis (EPMA), 3D surface profiler, X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR), and nanoindentation experiments respectively. Experimental results indicated that the amorphous thin films deposited at 0·5 Pa had a smooth surface and displayed the maximum hardness and Young's modulus of 35 and 322 GPa respectively. From the results of this work, high quality Al―Mg―B hard thin films can be obtained by magnetron sputtering under an optimum deposition pressure of 0·5 Pa.

Electronics, Electronique, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure electronique, proprietes electriques, magnetiques et optiques, Condensed matter: electronic structure, electrical, magnetic, and optical properties, Propriétés optiques, spectroscopie et autres interactions de la matière condensée avec les particules et le rayonnement, Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation, Propriétés optiques des structures de basse dimensionnalité, mésoscopiques, des nanostructures et nanomatériaux, Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Traitements de surface, Surface treatments, Sciences appliquees, Applied sciences, Electronique, Electronics, Electronique des semiconducteurs. Microélectronique. Optoélectronique. Dispositifs à l'état solide, Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices, Fabrication microélectronique (technologie des matériaux et des surfaces), Microelectronic fabrication (materials and surfaces technology), Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Surface treatment, Biomimétique, Biomimetics, Caractéristique optique, Optical characteristic, Característica óptica, Couche autoassemblée, Self-assembled layer, Capa autoensamblada, Dépôt sous vide, Vacuum deposition, Depósito bajo vacío, Vakuumbeschichtungsverfahren, Fabrication microélectronique, Microelectronic fabrication, Fabricación microeléctrica, Facteur réflexion, Reflectance, Coeficiente reflexión, Reflexionsfaktor, Gravure plasma, Plasma etching, Grabado plasma, Hydrophobicité, Hydrophobicity, Hidrofobicidad, Matériau revêtu, Coated material, Material revestido, Beschichteter Werkstoff, Micromanipulation, Micromanipulación, Mouillage, Wetting, Remojo, Mécanique précision, Precision engineering, Mecánica precisión, Feinmechanik, Méthacrylate de méthyle polymère, Methyl methacrylate polymer, Metacrilato de metilo polímero, Nanostructure, Nanoestructura, Oxygène, Oxygen, Oxígeno, Sauerstoff, Propriété optique, Optical properties, Propiedad óptica, Optische Eigenschaft, Revêtement, Coatings, Revestimiento, Ueberzug, Rugosité, Roughness, Rugosidad, Rauhigkeit, Tension superficielle, Surface tension, Tensión superficial, Oberflaechenspannung, Traitement par plasma, Plasma assisted processing, Verre, Glass, Vidrio, Glas, 8105K, 8116D, 8540H, Antireflective, Biomimetic, Oleophobic, Plasma nanotexturing, Superamphiphobic, and Superhydrophobic

Plasma nanotexturing, i.e. plasma etching with simultaneous roughening in the nano to micron scale, is used to create roughness on PMMA plates or glass slides coated with PMMA films. Mimicking nature, we use this roughness to create smart surfaces, with controlled optical and wetting properties. We present results that show combined antireflectivity, superhydrophobicity and superamphiphobicity for optimal plasma treatment time of only one-side of the samples (better results are expected for two-side treatment). In particular, using only 1.5 min of plasma nanotexturing and etching of PMMA in oxygen plasma, followed by vacuum deposition of a perfluorinated self-assembled monolayer, a reduction of reflectivity by 30% (compared to its initial value), superhydrophobicity and superamphiphobicity were achieved for liquids with surface tension more than 50 mN/m.

Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Diagrammes de phases et microstructures développées par solidification et par transformations de phases solide-solide, Phase diagrams and microstructures developed by solidification and solid-solid phase transformations, Solidification, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Autres traitements de surface, Other surface treatments, Anodisation, Anodizing, Couche oxyde, Oxide layer, Capa óxido, Oxidschicht, Oxyde anodique, Anodic oxide, Température, Temperature, Transformation Fourier, Fourier transformation, Anodization, Delaunay triangulations, Fast Fourier transform, Nanopores, Regularity, and Self-organization

An anodic aluminum oxide was formed by self-organized two step anodization in 0.3 M oxalic acid at four temperatures: 35, 40, 45 and 50 °C and three voltages: 30, 40 and 50 V. Duration of anodization steps was also varied: 30, 60 and 120 min. The influence of electrolyte temperature and duration of anodization on the nanoporous alumina arrangement was studied with three methods: regularity ratio derived from fast Fourier transform intensity profile, averaged regularity ratio evaluated from radial average of fast Fourier transform and defect maps (Delaunay triangulation). It was found that for sufficiently long anodization (60 min or longer) the better arrangement of the pores was obtained at higher temperatures. Additionally, the better arrangement of nanopores was obtained with the longer duration of the anodization step. The present results are rationalized by a phenomenological model and compared with the literature data.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Méthodes de dépôt de films et de revêtements; croissance de films et épitaxie, Methods of deposition of films and coatings; film growth and epitaxy, Traitements de surface, Surface treatments, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements thermiques, Heat treatment, Traitements thermochimiques et traitements par diffusion, Thermochemical treatment and diffusion treatment, Surface treatment, Acier non allié, Carbon steels, Activité catalytique, Catalyst activity, Actividad catalítica, Couche mince, Thin films, Dépôt physique phase vapeur, Physical vapor deposition, Magnétron, Magnetrons, Nitruration, Nitridation, Oxyde de titane, Titanium oxide, Titanio óxido, Titanoxid, Plasma, Prétraitement, Pretreatment, Pretratamiento, Pulvérisation irradiation, Sputtering, Traitement surface, Surface treatments, Traitement thermochimique, Thermochemical treatment, Tratamiento termoquímico, Thermochemische Behandlung, Carbon steel, Magnetron sputtering, Photocatalysis, Plasma nitriding, and TiO2

This paper presents a comparative study of TiO2 films deposited on plasma nitrided and non-nitrided carbon steel substrates. It is well known that plasma nitriding contributes to increase film adhesion and corrosion resistance of the substrate. However, most studies about photocatalytic properties of TiO2 on steel substrates do not address the use of nitrided carbon steel. The main goal of this paper is to investigate the deposition of photocatalytic TiO2 film on nitrided carbon steel, obtained through a duplex treatment of plasma nitriding and reactive plasma sputtering deposition. TiO2 films were deposited on nitrided and non-nitrided AISI 1015 steel samples. The samples were characterized by X-ray diffraction (XRD), profilometry, scanning electron microscopy (SEM) and atomic force microscopy (AFM). The photocatalytic activity was evaluated by monitoring the effect of photoinduced hydrophilicity and through the degradation of methylene blue dye (MB). The pretreatment by plasma nitriding increases the substrate surface roughness and improves the growth of rutile phase. The roughness of the substrate surface affects wettability only when the TiO2 film is not photoactivated. All samples become super-hydrophilic upon UV irradiation and remaining in this state for at least 24 h. A slightly higher performance in photocatalysis of MB is obtained by TiO2 film deposited on non-nitrided substrate.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Traitements de surface, Surface treatments, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Surface treatment, Borure de titane, Titanium boride, Titanio boruro, Titanborid, Carbure de titane, Titanium carbide, Titanio carburo, Titancarbid, Electrode, Electrodes, Matériau composite, Composite materials, Qualité, Quality, Calidad, Qualitaet, Revêtement composite, Composite coating, Revestimiento compuesto, Traitement surface, Surface treatments, Coating parameters, Coating quality, Copper alloy electrode, and Titanium diboride-titanium carbide

To improve the lifetime of electrodes used for the resistance spot welding of Zn-coated steel sheets, a TiB2―TiC composite coating was fused onto the surface of spot welding electrodes using an electro-spark deposition (ESD) process. Different processing parameters were studied in order to improve the quality of the electrode coating. The microstructure, elemental composition, phase structure, and mechanical properties of the coatings were characterized by scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD) and microhardness testing. When TiB2―TiC is deposited onto the electrodes in air, extensive coating defects occur within the bulk TiB2―TiC coating and at the interface with the electrode; however, coating defects are significantly reduced when the TiB2―TiC is deposited in argon. Delamination and oxidation of the TiB2―TiC coating were prevented and the number of cracks diminished. When TiB2―TiC was deposited in air on an electrode pre-coated with Ni, almost all coating defects were eliminated. The TiB2―TiC coated directly onto electrodes in air was found to have the lowest average microhardness of HV50 650, and the average hardness values obtained in argon and with Ni-coated electrodes were about HV50 1050 and HV50 1080, respectively. A heat-affected zone (HAZ) of about 20 μm in depth within the substrate was observed near the interface between the coating and the substrate for all coating conditions.

Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Diagrammes de phases et microstructures développées par solidification et par transformations de phases solide-solide, Phase diagrams and microstructures developed by solidification and solid-solid phase transformations, Solidification, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Traitements de surface, Surface treatment, Etat surface, Surface states, Fusion laser, Laser fusion, Rugosité, Roughness, 3D morphological analysis, Micro computed tomography, Porous structures, Selective laser melting, Spatial resolution, and Surface roughness

In material science microfocus X-ray computed tomography (micro-CT) is one of the most popular non-destructive techniques to visualise and quantify the internal structure of materials in 3D. Despite constant system improvements, state-of-the-art micro-CT images can still hold several artefacts typical for X-ray CT imaging that hinder further image-based processing, structural and quantitative analysis. For example spatial resolution is crucial for an appropriate characterisation as the voxel size essentially influences the partial volume effect. However, defining the adequate image resolution is not a trivial aspect and understanding the correlation between scan parameters like voxel size and the structural properties is crucial for comprehensive material characterisation using micro-CT. Therefore, the objective of this study was to evaluate the influence of the spatial image resolution on the micro-CT based morphological analysis of three-dimensional (3D) open porous structures with a high surface complexity. In particular the correlation between the local surface properties and the accuracy of the micro-CT-based macro-morphology of 3D open porous Ti6Al4V structures produced by selective laser melting (SLM) was targeted and revealed for rough surfaces a strong dependence of the resulting structure characteristics on the scan resolution. Reducing the surface complexity by chemical etching decreased the sensitivity of the overall morphological analysis to the spatial image resolution and increased the detection limit. This study showed that scan settings and image processing parameters need to be customized to the material properties, morphological parameters under investigation and the desired final characteristics (in relation to the intended functional use). Customization of the scan resolution can increase the reliability of the micro-CT based analysis and at the same time reduce its operating costs.

Crystallography, Cristallographie cristallogenèse, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure, proprietes mecaniques et thermiques, Condensed matter: structure, mechanical and thermal properties, Surfaces et interfaces; couches minces et trichites (structure et propriétés non électroniques), Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties), Structure et morphologie de couches minces, Thin film structure and morphology, Structure et morphologie; épaisseur, Structure and morphology; thickness, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Méthodes de dépôt de films et de revêtements; croissance de films et épitaxie, Methods of deposition of films and coatings; film growth and epitaxy, Théorie et modèles de la croissance de films, Theory and models of film growth, Sciences appliquees, Applied sciences, Electronique, Electronics, Appareillage électronique et fabrication. Composants passifs, circuits imprimés, connectique, Electronic equipment and fabrication. Passive components, printed wiring boards, connectics, Alcool, Alcohols, Alumine, Alumina, Boehmite, Boehmita, Capacité électrique, Capacitance, Condensateur, Capacitors, Couche barrière, Barrier layer, Couche mince, Thin films, Cristallisation, Crystallization, Diffraction RX, XRD, Ethane-«1,2»-diol, Ethylene glycol, Mesure capacité électrique, Capacitance measurement, Morphologie surface, Surface morphology, Mécanisme croissance, Growth mechanism, Mecanismo crecimiento, Propriété diélectrique, Dielectric properties, Traitement surface, Surface treatments, 6855A, 6855J, 8115A, 8432T, Al2O3, Substrat Aluminium, Anodic alumina, Dielectric, and Surface treatment

Hydrous films were grown on high purity and cubicity Al foils for electrolytic capacitors in deionized water, ethylene glycol-deionized water and glycerol-deionized water at different immersion times. According to X-ray diffraction patterns the hydration treatment allowed growing a pseudo boehmite layer on Al surface whose morphology is appreciably affected by the bath composition. Capacitance measurements and photoelectrochemical findings suggest that a more compact barrier layer forms during the immersion in alcohol containing solutions. The hydration in water allowed saving energy and preparing more blocking oxide films. The beneficial effect of hydration in hot water on the specific capacitance was evidenced only for films formed at 300 V due to the crystallization of amorphous alumina in γ'-Al2O3.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Traitements de surface, Surface treatments, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Transformation de matériaux métalliques, Production techniques, Surface treatment, Corrosion, Action des agents de corrosion, Corrosion environments, Alliage base aluminium, Aluminium base alloys, Corrosion, Dépôt conversion, Conversion coating, Depósito conversión, Konversionsbeschichten, Revêtement, Coatings, Température, Temperature, Traitement surface, Surface treatments, Aluminum 2024, Nanosilica, and Silicate conversion coatings

Nanosilica modified potassium silicate conversion coatings were deposited on the surface of 2024 aluminum alloy. The corrosion behavior of coatings was studied by electrochemical impedance spectroscopy, potentiodynamic polarization and the surface analyzing techniques. The effect of curing time and the curing temperature was studied on anti-corrosion behavior of coatings. Curing temperature showed a significant effect in silicate conversion coating and higher corrosion resistance was obtained with 150 °C curing temperature. Also the experimental results indicated that the corrosion resistance was increased with increasing the curing time. This behavior can be related to the increase of the silicate coating continuity and reinforcement of the siloxane chains which formed on the surface. Surface analysis results indicated that the coating obtained from 2.33 silica ratio was more uniform and continuous.