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Physics, Physique, 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, Traitement des matériaux et son effet sur la microstructure et les propriétés, Treatment of materials and its effects on microstructure and properties, 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), Lithography, masks and pattern transfer, Carbone, Carbon, Carbono, Dépôt électrolytique, Electrodeposition, Depósito electrolítico, Etat vitreux, Glassy state, Estado vitreo, Etude expérimentale, Experimental study, Estudio experimental, Fabrication, Manufacturing, Fabricación, Lithographie, Lithography, Litografía, Microstructure, Microestructura, Mode mou, Soft mode, Modo blando, Moulage, Molding, and Moldeo

This paper describes fabrication techniques for the fabrication of glassy carbon microstructures. Molding of a resin of poly(furfuryl alcohol) using elastomeric molds yields polymeric microstructures, which are converted to free-standing glassy carbon microstructures by heating (T ∼ 500-1100°C) under argon. This approach allows the preparation of macroscopic structures (several mm2) with microscopic features (∼ 2 μm). Deformation of the molds during molding of the resin allows preparation of curved microstructures. The paper also presents a method of incorporating these structures on a chip by masking and electroplating.

Electronics, Electronique, Mechanical engineering, Génie mécanique, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines classiques de la physique (y compris les applications), Fundamental areas of phenomenology (including applications), Mécanique des fluides, Fluid dynamics, Mécanique des fluides appliquée, Applied fluid mechanics, Fluidique, Fluidics, Sciences appliquees, Applied sciences, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Mécanique de précision. Horlogerie, Precision engineering, watch making, Electroosmose, Electroosmosis, Electro-osmosis, Etude expérimentale, Experimental study, Estudio experimental, Fluidique, Fluidics, Fluídico, Miniaturisation, Miniaturization, Miniaturización, Mécanique précision, Precision engineering, Mecánica precisión, Photofabrication, Fotofabricación, Photolithographie, Photolithography, Fotolitografía, Photorésist, Photoresist, Fotorresistente, Processus fabrication, Production process, Proceso fabricación, Prototypage rapide, Rapid prototyping, Prototipificación rápida, Siloxane(diméthyl) polymère, Dimethylsiloxane polymer, Siloxano(dimetil) polímero, Solution aqueuse, Aqueous solution, and Solución acuosa

This paper describes a procedure for rapidly and conveniently prototyping microfluidic devices that are useful with aqueous solutions. A design (with diameters of channels ≥20 μm) is created in a computer-aided design program and printed at high resolution on a transparency. This transparency is used as a mask in photolithography to create a master in positive relief photoresist: casting poly(dimethyl siloxane) (PDMS) against this master yields a polymeric replica containing a network of bas-relief channels. The channels are closed and sealed irreversibly by oxidizing the replica and another flat substrate (PDMS, glass, silicon, silicon oxide) in an oxygen plasma and bringing the two surfaces into conformal contact. Oxidation of the polymer allows the formation of a seal without using adhesives; it also generates channels that support electro-osmotic flow (EOF) and fill easily with aqueous solutions. Two microfluidic devices-a fluidic switch and a side channel flow controller-have been fabricated using this rapid prototyping methodology. These devices were tested using aqueous solutions as the test fluid and actuated by EOF.

Analytical chemistry, Chimie analytique, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie analytique, Analytical chemistry, Généralités, appareillage, General, instrumentation, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Biochimie analytique, structurale et metabolique, Analytical, structural and metabolic biochemistry, Biochimie analytique: généralités, techniques, appareillages, Analytical biochemistry: general aspects, technics, instrumentation, Génie biomédical, Biomedical engineering, Ingeniería biomédica, Aminoacide, Aminoacid, Aminoácido, Conception miniaturisée, Miniaturized design, Concepción miniaturizada, Conception, Design, Diseño, DNA, Electrophorèse capillaire, Capillary electrophoresis, Electroforesis capilar, Electrophorèse, Electrophoresis, Electroforesis, Fabrication, Manufacturing, Fabricación, Mastic base élastomère, Elastomeric sealant, Masilla base elastomer, Microfluide, Microfluid, Microfluido, Prototypage rapide, Rapid prototyping, Prototipificación rápida, Siloxane(diméthyl) polymère, Dimethylsiloxane polymer, Siloxano(dimetil) polímero, Structure microscopique, Microscopic structure, Estructura microscópica, Tube capillaire, Capillary tube, and Tubo capilar

This paper describes a procedure that makes it possible to design and fabricate (including sealing) microfluidic systems in an elastomeric material-poly(dimethylsiloxane) (PDMS)-in less than 24 h. A network of microfluidic channels (with width >20 μm) is designed in a CAD program. This design is converted into a transparency by a high-resolution printer; this transparency is used as a mask in photolithography to create a master in positive relief photoresist. PDMS cast against the master yields a polymeric replica containing a network of channels. The surface of this replica, and that of a flat slab of PDMS, are oxidized in an oxygen plasma. These oxidized surfaces seal tightly and irreversibly when brought into conformal contact. Oxidized PDMS also seals irreversibly to other materials used in microfluidic systems, such as glass, silicon, silicon oxide, and oxidized polystyrene; a number of substrates for devices are, therefore, practical options. Oxidation of the PDMS has the additional advantage that it yields channels whose walls are negatively charged when in contact with neutral and basic aqueous solutions; these channels support electroosmotic pumping and can be filled easily with liquids with high surface energies (especially water). The performance of microfluidic systems prepared using this rapid prototyping technique has been evaluated by fabricating a miniaturized capillary electrophoresis system. Amino acids, charge ladders of positively and negatively charged proteins, and DNA fragments were separated in aqueous solutions with this system with resolution comparable to that obtained using fused silica capillaries.

Physics, Physique, 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, Etats électroniques, Electron states, Densités d'états électroniques et structure de bandes des solides cristallins, Electron density of states and band structure of crystalline solids, Polymères et composés organiques, Polymers and organic compounds, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Traitement des matériaux et son effet sur la microstructure et les propriétés, Treatment of materials and its effects on microstructure and properties, Effet dimensionnel, Size effect, Etude expérimentale, Experimental study, Film rétractable, Shrinkable film, Película retráctil, Gravure ionique réactive, Reactive ion etching, Grabado iónico reactivo, Microstructure, Moulage, Molding, Polymère, Polymers, Réplique, and Replicas

This paper demonstrates the combination of reactive ion etching (RIE) and shrinkable polystyrene (PS) films to reduce the feature size of microstructures and to generate microstructures with high aspect ratios on both planar and curved surfaces. A shrinkable PS film is patterned with relief structures using RIE through aphysical mask. The patterned surface is heated and shrinks. After shrinking, the size of microstructures decreases by a factor of four to five, and their height increases by a factor of ∼20. Thermal shrinkage results in a 100-fold increase in the aspect ratio of the patterned microstructures in the PS film. Microstructures as high as 126 μm with aspect ratio of ∼9.5 have been generated. The smallest structures fabricated using this strategy are rectangular pits ∼ 1.4 μm X 1.7 μm in size. Fabrication of microstructures on curved surfaces has been demonstrated by folding a patterned PS film and allowing it to shrink in place.

Chemistry, Chimie, Electronics, Electronique, Physics, Physique, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, 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), Carbone, Carbon, Carbono, Etat vitreux, Glassy state, Estado vitreo, Etude expérimentale, Experimental study, Estudio experimental, Fabrication microélectronique, Microelectronic fabrication, Fabricación microeléctrica, Microstructure, Microestructura, Polymère, Polymer, Polímero, Pyrolyse, Pyrolysis, Pirólisis, and Microélectromécanique

Chemistry, Chimie, Chemical industry parachemical industry, Industrie chimique et parachimique, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères minéraux et organominéraux, Inorganic and organomineral polymers, Modifications chimiques, Chemical modifications, Carbone composé, Carbon compound, Carbono compuesto, Carbonisation, Carbonization, Carbonización, Fabrication, Manufacturing, Fabricación, Furannique résine, Furan resin, Furánico resina, Lithographie, Lithography, Litografía, Microstructure, Microestructura, Précurseur, Precursor, Siloxane(diméthyl) polymère, Dimethylsiloxane polymer, Siloxano(dimetil) polímero, and Microfabrication

Chemistry, Chimie, Chemical industry parachemical industry, Industrie chimique et parachimique, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Théorie des réactions, cinétique générale. Catalyse. Nomenclature, documentation chimique, informatique chimique, Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry, Catalyse, Catalysis, Catalyseurs: préparations et propriétés, Catalysts: preparations and properties, Métal zérovalent Complexe, Zerovalent metal Complexes, Metal cerovalente Complejo, Activité catalytique, Catalyst activity, Actividad catalítica, Agrégat complexe, Complex cluster, Agregado complejo, Carbone, Carbon, Carbono, Etat vitreux, Glassy state, Estado vitreo, Microscopie électronique transmission, Transmission electron microscopy, Microscopía electrónica transmisión, Phénylène polymère, Phenylene polymer, Fenileno polímero, Platine Complexe, Platinum Complexes, Platino Complejo, Préparation, Preparation, Preparación, Pyrolyse, Pyrolysis, Pirólisis, and Benzène(diéthynyl tétrafluoro) polymère

Chemistry, Chimie, Chemical industry parachemical industry, Industrie chimique et parachimique, Polymers, paint and wood industries, Polymères, industries des peintures et bois, 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), Surfaces solides et interfaces solide-solide, Solid surfaces and solid-solid interfaces, Dynamique et vibrations de surface et d'interface, Surface and interface dynamics and vibrations, Structure et morphologie de couches minces, Thin film structure and morphology, Non métal, Non metal, No metal, Agrégat atomique, Atomic cluster, Agregado atómico, Carbone, Carbon, Carbono, Couche mince, Thin film, Capa fina, Cristallochimie, Crystal chemistry, Cristaloquímica, Diffraction électron, Electron diffraction, Difracción electrónica, Etat amorphe, Amorphous state, Estado amorfo, Etude expérimentale, Experimental study, Estudio experimental, Microscopie électronique transmission, Transmission electron microscopy, Microscopía electrónica transmisión, Molécule polyédrique, Polyhedral molecule, Molécula poliédrica, Platine Molécule, Platinum Molecules, Platino Molécula, Rayon X, X ray, Rayos X, Spectrométrie photoélectron, Photoelectron spectrometry, Espectrometría fotoelectrón, Verre, Glass, and Vidrio