articles+ search results

Electronics, Electronique, Metrology and instrumentation, Métrologie et instrumentation, Optics, Optique, Physics, Physique, Telecommunications, Télécommunications, 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, Dispositifs micro- et nanoélectromécaniques (mems/nems), Micro- and nanoelectromechanical devices (mems/nems), Actionneur, Actuator, Accionador, Aluminium nitrure, Aluminium nitride, Aluminio nitruro, Contrainte résiduelle, Residual stress, Tensión residual, Dispositif microélectromécanique, Microelectromechanical device, Dispositivo microelectromecánico, Etude théorique, Theoretical study, Estudio teórico, Microusinage, Micromachining, Micromaquinado, Méthode élément fini, Finite element method, Método elemento finito, Nitrure, Nitrides, Nitruro, Piézoélectrique, Piezoelectric materials, Piezoeléctrica, Propriété mécanique, Mechanical properties, Propiedad mecánica, Silicium, Silicon, Silicio, Traitement surface, Surface treatment, Tratamiento superficie, AlN, and Substrat Silicium

Aluminum nitride is lately being considered as a promising candidate for its use as the actuator in piezoelectrically-actuated MEMS due to its good piezoelectric and mechanical properties, high chemical stability and full compatibility with conventional silicon technologies. In this work we present the mechanical response of doubly-clamped microbridges with piezoelectric actuation by a sputtered AlN film. A complete technology for the fabrication of the microbridges on silicon substrates using surface micromachining has been developed. The mechanical response of the microbridges under electrical excitation has been measured. Finite element method (FEM) computations have been carried out in order to analyze the static and dynamic response of devices with several configurations and to determine their optimum design. These simulations include the influence of the properties of the materials, the initial residual stress and the different geometries on the device operation. Although the qualitative behavior of the microbridges is well predicted, a significant discrepancy is observed between the measured displacement of the beam and the simulated response. The measured values of the out-of-plane displacement of the bridge are near ten times greater than those obtained in the simulations. Some of the possible causes of these discrepancies are widely discussed.

Electronics, Electronique, Optics, Optique, Physics, Physique, 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, Microélectronique du vide, Vacuum microelectronics, Caractéristique fonctionnement, Performance characteristic, Característica funcionamiento, Comportement thermique, Thermal behavior, Comportamiento térmico, Couche mince, Thin film, Capa fina, Cuisson au four, Baking, Cocimiento al horno, Défaut surface, Surface defect, Defecto superficie, Emission champ, Field emission, Emisión campo, Etat surface, Surface conditions, Estado superficie, Evaluation performance, Performance evaluation, Evaluación prestación, Fiabilité, Reliability, Fiabilidad, Gain, Ganancia, Galette microcanaux, Microchannel plates, In situ, Microscopie force atomique, Atomic force microscopy, Microscopía fuerza atómica, Méthode analytique, Analytical method, Método analítico, Procédé fabrication, Manufacturing process, Procedimiento fabricación, Qualité image, Image quality, Calidad imagen, Rugosité, Roughness, Rugosidad, Rétroaction, Feedback regulation, Retroacción, Stabilité thermique, Thermal stability, Estabilidad térmica, Traitement chimique, Chemical treatment, Tratamiento químico, Traitement surface, Surface treatment, and Tratamiento superficie

The basic physical-and-chemical aspects of influence of microchannel plate working surface quality on a complex of parameters determining a technological level, quality and reliability of plates are considered in this paper. A radically new approach to technology consisting in directional change of composition and properties of channel wall material directly in the course of MCP manufacturing process is presented. Technical level, quality and reliability of MCP are eventually evaluated by quality and purity of working surface including resistive-emissive layer of MCP channels and input-output faces. Working surface characteristics are in many respects responsible for MCP performances such as picture quality of electron image, gain and gain stability in longtime operation, noise characteristics (field-emission effects, ion feedback), outgassing as well as thermal stability of performance in vacuum baking degassing. Thus, working surface condition is one of the key MCP characteristics which quality enhancement can not be attained without understanding physical and chemical processes and in absence of system approach to this problem. Over a period of years regular studies of MCP working surfaces and their characteristics have been carried out in the following directions: surface relief on micro and nano-level; chemical and structural surface defects and their classification; in situ and integral diagnostics on the basic of currently available methods of surface diagnostics and studies of MCP characteristics; influence of technological factors and various methods of physical and chemical treatments on surface condition; MCP channel walls outgassing; MCP surface behavior in storage under exposure to air. The thickness of the wall between channels does not exceed 1.0 - 1.6-μm, therefore, in terms of physics the channel wall is a thin-film element or a physical surface. The analysis made with the aid of atomic force microscopy and other currently available physical and analytical methods [1] showed that channel wall surface of domestic and foreign MCP have bad roughness on nano-level with relief height of order 2-10 nanometer (see Fig. 1).

Electronics, Electronique, Metrology and instrumentation, Métrologie et instrumentation, Optics, Optique, Physics, Physique, Telecommunications, Télécommunications, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Generalites, General, Instruments, appareillage, composants et techniques communs à plusieurs branches de la physique et de l'astronomie, Instruments, apparatus, components and techniques common to several branches of physics and astronomy, Techniques et équipements généraux, General equipment and techniques, Capteurs (chimiques, optiques, électriques, de mouvement, de gaz, etc.); télédétection, Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing, Sciences appliquees, Applied sciences, Electronique, Electronics, Electronique des semiconducteurs. Microélectronique. Optoélectronique. Dispositifs à l'état solide, Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices, Interfaces, Electronique moléculaire, nanoélectronique, Molecular electronics, nanoelectronics, Circuits électriques, optiques et optoélectroniques, Electric, optical and optoelectronic circuits, Propriétés des circuits, Circuit properties, Circuits optiques et optoélectroniques, Optical and optoelectronic circuits, Optoélectronique intégrée. Circuits optoélectroniques, Integrated optoelectronics. Optoelectronic circuits, Analyse gaz, Gas analysis, Análisis gas, Capteur mesure, Measurement sensor, Captador medida, Capteur tactile, Tactile sensor, Sensor tactil, Caractéristique optique, Optical characteristic, Característica óptica, Commande courant, Current control, Control corriente, Contact électrique, Electric contact, Contacto eléctrico, Dépendance du temps, Time dependence, Dependencia del tiempo, Electronique moléculaire, Molecular electronics, Electrónica molecular, Etat excité, Excited state, Estado excitado, Fabrication microélectronique, Microelectronic fabrication, Fabricación microeléctrica, Impédance, Impedance, Impedancia, Matériau poreux, Porous material, Material poroso, Matériau revêtu, Coated material, Material revestido, Métallisation, Metallizing, Metalización, Nanostructure, Nanoestructura, Nanotechnologie, Nanotechnology, Nanotecnología, Nanoélectronique, Nanoelectronics, Nanoelectrónica, Optoélectronique, Optoelectronics, Optoelectrónica, Photoluminescence, Fotoluminiscencia, Propriété électrochimique, Electrochemical properties, Propiedad electroquímica, Structure surface, Surface structure, Estructura superficie, Structure électronique, Electronic structure, Estructura electrónica, Tension polarisation, Bias voltage, Voltage polarización, Traitement surface, Surface treatment, Tratamiento superficie, Transformation Fourier rapide, Fast Fourier transformation, Transformación Fourier rápida, and 0707D

The ability to control and transform the morphology and optical properties of porous silicon (PS) interface arrays can have important implications for displays and sensors..The optoelectronic properties and interaction sensing capabilities of PS can be varied as a function of pore size and pore morphology as dictated by the manipulation of a surface structure which can be controlled with current density, the solution composition of the electrochemical etches used to prepare the pores, and careful post etch surface treatments. These treatments influence the time dependent photoluminescence (PL) emission from PS. The variation of surface structure as it effects the PL from these PS pore arrays is outlined and discussed within the framework of detailed molecular electronic structure calculations which model the excited state structure giving rise to the UV-visible PL emission from PS. Applications varying from displays to sensors to micro-reactors will be considered. Porous silicon interfaces have also been transformed within the framework of nanotechnology to create highly efficient sensors displaying a rapid, reversible, sensitive, and selective response to HCl, NH3, CO, and NO down to the ppb level. Photoluminescence induced metallization is used to obtain a highly efficient, <20Ω, electrical contact to the sensor, allowing operation at a bias voltage of 1-10mV. The introduction of gold and tin-based nanostructures to a micro/nanoporous PS array selectively modifies its impedance response to considerably improve the detection of the NH3, CO, and NO. Through FFT analysis, a gas response can be acquired and filtered on a drifting baseline, further improving sensitivity. New nanoscale exclusive techniques have been developed for the rapid formation of highly efficient TiO2-xNx nanophotocatalysts, operative and tunable throughout the visible wavelength region, to be used in conjunction with porous silicon hybrid nanopore coated micropores to form novel and efficient solar pumped sensor arrays.

Electronics, Electronique, Optics, Optique, Physics, Physique, Telecommunications, Télécommunications, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Electronique, Electronics, Circuits électriques, optiques et optoélectroniques, Electric, optical and optoelectronic circuits, Propriétés des circuits, Circuit properties, Circuits optiques et optoélectroniques, Optical and optoelectronic circuits, Optoélectronique intégrée. Circuits optoélectroniques, Integrated optoelectronics. Optoelectronic circuits, Couche mince transparente, Transparent thin film, Película transparente, Erreur mesure, Measurement error, Error medida, Implémentation, Implementation, Implementación, In situ, Interférométrie, Interferometry, Interferometría, Lumière blanche, White light, Luz blanca, Matériau composite, Composite material, Material compuesto, Matériau revêtu, Coated material, Material revestido, Métrologie surface, Surface metrology, Metrología superficie, Packaging électronique, Electronic packaging, Packaging electrónico, Traitement surface, Surface treatment, and Tratamiento superficie

Current technological issues arising to meet rapidly grwoing demand on 3-D measurements in the field of microelectronics packaging and integration are addressed with special emphasis on white-light interferometry. We first discuss the problem of phase change upon reflection which causes significant measurement errors unless properly compensated for measuring composite targets made of dissimilar materials. Next, an extended application of white-light interferometry is described with aims of measuring not only the surface height profile but also the thickness profile of target surfaces coated with transparent thin-film layers. Finally addressed is the dispersive white-light interferometry that draws much attention for high-speed implementation of surface metrology, which is found useful for in-situ inspection of micro-engineered surfaces.

Electronics, Electronique, Optics, Optique, Physics, Physique, Telecommunications, Télécommunications, 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), Optique, Optics, Lasers, Lasers à semiconducteur; diodes laser, Semiconductor lasers; laser diodes, Sources optiques et étalons, Optical sources and standards, Sciences appliquees, Applied sciences, Electronique, Electronics, Electronique des semiconducteurs. Microélectronique. Optoélectronique. Dispositifs à l'état solide, Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices, Autres dispositifs multijonctions. Transistors de puissance. Thyristors, Other multijunction devices. Power transistors. Thyristors, Dispositifs à images, Imaging devices, Analyse système, System analysis, Análisis sistema, Application médicale, Medical application, Aplicación medical, Diminution coût, Cost lowering, Reducción costes, Diode puissance, Power diode, Diodo potencia, Distribution densité, Density distribution, Distribución densidad, Distribution vitesse, Velocity distribution, Distribución velocidad, Ecoulement gaz, Gas flow, Flujo gas, Ecoulement turbulent, Turbulent flow, Flujo turbulento, Formation image, Imaging, Formación imagen, Imageur, Imager, Interaction particule, Particle interaction, Interacción partícula, Laser déclenché, Q switched laser, Laser disparado, Laser injection, Injection laser, Laser inyección, Laser puissance, Power laser, Laser potencia, Laser solide, Solid state laser, Laser sólido, Source lumineuse, Light source, Fuente luminosa, Traitement matériau, Material processing, Tratamiento material, Traitement surface, Surface treatment, Tratamiento superficie, 4255P, Imagerie optique, and Optical imaging

Spray processes are commonly employed in many kinds of surface treatment applications, most prominently in medical, material processing and manufacturing industries. While spraying is a well established technology, we still lack complete understanding of all interactions within a given spray process. This is because the physical models of many subprocesses, like turbulent gas flow, particle formation and gas-particle interaction, are limited and often provide only qualitative predictions on the real process. Imaging measurements are essential in gaining better understanding of a spray process. They offer a way to measure properties of both the complete spray plume and individual droplets. A spray analysis system typically requires a high-power stroboscopic light source; Xe flashlamps and Q-switched solid state lasers have been the most common choice until recently. The development of high-power diode lasers has provided a versatile, low-cost and easy to use light source for the analysis of spray processes. We present a real-time diode laser based imaging system to measure droplet density, size and velocity distributions in a spray, together with the spray plume geometry.

Electronics, Electronique, Metrology and instrumentation, Métrologie et instrumentation, Optics, Optique, Physics, Physique, Telecommunications, Télécommunications, 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, Dispositifs micro- et nanoélectromécaniques (mems/nems), Micro- and nanoelectromechanical devices (mems/nems), Aluminium oxyde, Aluminium oxide, Aluminio óxido, Composé binaire, Binary compound, Compuesto binario, Dispositif microélectromécanique, Microelectromechanical device, Dispositivo microelectromecánico, Germanium oxyde, Germanium oxide, Germanio óxido, Microusinage, Micromachining, Micromaquinado, Piézoélectrique, Piezoelectric materials, Piezoeléctrica, Polissage, Polishing, Pulimiento, Poudre, Powder, Polvo, Spectre IR, Infrared spectrum, Espectro IR, Spectrométrie transformée Fourier, Fourier transform spectroscopy, Température ambiante, Room temperature, Temperatura ambiente, Traitement surface, Surface treatment, Tratamiento superficie, Al O, Al2O3, AlN, Ge O, and GeO2

In this article we present a study of deposition and etching techniques of germanium (Ge) and amorphous oxygen germanium (GeOx) films, with the aim of using them as sacrificial layer in the fabrication of AIN-based MEMS by surface micromachining processes. The Ge and GeOx layers were deposited by RF magnetron sputtering in Ar and Ar/O2 atmospheres. By controlling the process parameters we were able to set the final composition of the GeOx films, which was assessed by FTIR measurements. We have studied the etch rates of GeOx films with x ranging from 0 to 1 in H2O2 and H2O2/acid solutions. Depending on the etching temperature and the oxygen content in the layers, etch rates ranging from 0.2 to 2 μm/min were obtained. Nearly stoichiometric germanium oxide (GeO2) was etched in pure H2O at very high rate (>1 μm/min at room temperature). We have also developed a chemomechanical polishing (CMP) process for the planarization of Ge and GeOx. The influence of the slurries containing diverse powders (CeO2, Al2O3) and chemical agents (NH4OH, HCl), the different pads, and the various process parameters on the removal rate and the final sample topography has been studied. Finally, we have analysed the compatibility of the materials involved in the process flow with the processes of planarization and removal of the sacrificial layers.

Electronics, Electronique, Optics, Optique, Physics, Physique, Telecommunications, Télécommunications, 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), Optique, Optics, Matériaux optiques, Optical materials, Matériaux à bande interdite photonique interdite, Photonic bandgap materials, Sciences appliquees, Applied sciences, Electronique, Electronics, Matériaux, Materials, Circuits électriques, optiques et optoélectroniques, Electric, optical and optoelectronic circuits, Propriétés des circuits, Circuit properties, Circuits optiques et optoélectroniques, Optical and optoelectronic circuits, Optique intégrée. Fibres et guides d'onde optiques, Integrated optics. Optical fibers and wave guides, Champ libre, Free field, Campo libre, Couche mince métallique, Metallic thin films, Cristal photonique, Photonic crystal, Cristal fotónico, Emission optique, Light emission, Emisión óptica, Evaluation performance, Performance evaluation, Evaluación prestación, Guide onde optique, Optical waveguide, Guía onda óptica, Guide onde, Waveguide, Guía onda, Optique intégrée, Integrated optics, Optica integrada, Structure surface, Surface structure, Estructura superficie, Technologie matériau, Material engineering, Tecnología material, Traitement surface, Surface treatment, Tratamiento superficie, and 4270Q

It is known that free-space focusing of light from sub-wavelength apertures, the so-called beaming effect of liqht, can be achieved through the excitation of radiative surface modes and their subsequent constructive interference in space surrounding the apertures. This effect, studied extensively in metallic thin films, has recently been shown to exist in photonic-crystal structures. In this paper, we present a comprehensive study of the beaming effect and light directional emission achieved through simple geometric and material engineering of the surface and near-surface structures in two types of photonic-crystal waveguides, classified as increased- and decreased-index structures. We analyze different methods to enhance the directional emission and calculate the resulting efficiencies, highlighting the influence of reflections and matching conditions at the waveguide terminations.

Electronics, Electronique, Computer science, Informatique, Metrology and instrumentation, Métrologie et instrumentation, Optics, Optique, Physics, Physique, Telecommunications, Télécommunications, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Informatique; automatique theorique; systemes, Computer science; control theory; systems, Intelligence artificielle, Artificial intelligence, Reconnaissance des formes. Traitement numérique des images. Géométrie algorithmique, Pattern recognition. Digital image processing. Computational geometry, Metaux. Metallurgie, Metals. Metallurgy, Contrôle, Analysing. Testing. Standards, Contrôle non destructif, Nondestructive testing, Recherche des défauts, Testing for defects, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Métrologie industrielle. Contrôle, Industrial metrology. Testing, Contrôle non destructif: méthodes et appareillages, Non-destructive testing: methods and equipments, Acier, Steel, Acero, Analyse sensibilité, Sensitivity analysis, Análisis sensibilidad, Analyse statistique, Statistical analysis, Análisis estadístico, Statistische Analyse, Analyse texture, Texture analysis, Análisis textura, Approche probabiliste, Probabilistic approach, Enfoque probabilista, Automatisation, Automation, Automatización, Automatisierung, Banque image, Image databank, Banco imagen, Classification, Clasificación, Klassifizierung, Construction métallique, Metallic structure, Construcción metálica, Stahlbau, Corrosion, Corrosión, Korrosion, Essai non destructif, Non destructive test, Ensayo no destructivo, Zerstoerungsfreie Pruefung, Mesure automatique, Automatic measurement, Medición automática, Automatisches Messen, Modélisation, Modeling, Modelización, Navire, Ship, Navío, Schiff, Optimisation, Optimization, Optimización, Optimierung, Réservoir stockage, Storage tank, Tanque almacenamiento, Lagerbehaelter, Temps exécution, Execution time, Tiempo ejecución, Temps réponse, Response time, Tiempo respuesta, Traitement image, Image processing, Procesamiento imagen, Bildverarbeitung, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Vision ordinateur, Computer vision, and Visión ordenador

The exposure of metallic structures to rust degradation during their operational life is a known problem and it affects storage tanks, steel bridges, ships, etc. In order to prevent this degradation and the potential related catastrophes, the surfaces have to be assessed and the appropriate surface treatment and coating need to be applied according to the corrosion time of the steel. We previously investigated the potential of image processing techniques to tackle this problem. Several mathematical algorithms methods were analyzed and evaluated on a database of 500 images'. In this paper, we extend our previous research and provide a further analysis of the textural mathematical methods for automatic rust time steel detection. Statistical descriptors are provided to evaluate the sensitivity of the results as well as the advantages and limitations of the different methods. Finally, a selector of the classifiers algorithms is introduced and the ratio between sensitivity of the results and time response (execution time) is analyzed to compromise good classification results (high sensitivity) and acceptable time response for the automation of the system.

Electronics, Electronique, Optics, Optique, Physics, Physique, Telecommunications, Télécommunications, 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), Composé binaire, Binary compound, Compuesto binario, Evaluation performance, Performance evaluation, Evaluación prestación, Fabrication microélectronique, Microelectronic fabrication, Fabricación microeléctrica, Faisceau atomique, Atomic beam, Haz atómico, Gallium arséniure, Gallium arsenides, Nettoyage surface, Surface cleaning, Limpieza superficie, Photolithographie, Photolithography, Fotolitografía, Photorésist, Photoresist, Fotorresistencia, Silicium, Silicon, Silicio, Traitement surface, Surface treatment, Tratamiento superficie, As Ga, Diélectrique basse permittivité, Low k dielectric, Dieléctrico baja constante dieléctrica, GaAs, and Si

Residual resist removal availability from surface of semiconductor structures Si and GaAs by directed hydrogen atomic flow has been shown. The influence of treatment time and temperature on surface cleaning efficiency was studied. It has been shown that cleaning by atomic hydrogen flow leads to surface of GaAs roughness reduction. Comparative studies of residual photoresist removal efficiency by oxygen plasma, ozone and atomic hydrogen have been carried out. Organic contaminants removal efficiency by atomic hydrogen is comparable to the efficiency of traditionally used cleaning method by oxygen plasma. The merits of treatment by AH flow are compatibility of the process with technology of low-k dielectrics, absence of surface oxidation of semiconductor materials, and minimization of energy and charged particles effect on semiconductor structure.

Electronics, Electronique, Optics, Optique, Physics, Physique, Telecommunications, Télécommunications, 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), Capteur mesure, Measurement sensor, Captador medida, Dispositif micromécanique, Micromechanical devices, Dispositif semiconducteur, Semiconductor device, Dispositivo semiconductor, Système intelligent, Intelligent system, Sistema inteligente, Technologie silicium sur isolant, Silicon on insulator technology, Tecnología silicio sobre aislante, Traitement chimique, Chemical treatment, Tratamiento químico, Traitement surface, Surface treatment, Tratamiento superficie, Traitement thermique, Heat treatment, and Tratamiento térmico

The proposed lower methods of silicon surface formation using heat treatment in wet environment (including chemical surface assembling by the molecular deposition method) and the smart technique allow producing high-quality SOI-structures suitable for using in special ICs, semiconductor devices, micromechanical systems and sensors. The basic idea of the chemical surface assembling by the molecular deposition method that may be suitable for precision synthesis of surface of required composition and for surface modification consist in consecutive deposition of monolayers of structural units with given chemical composition [1-3].

Electronics, Electronique, Optics, Optique, Physics, Physique, Telecommunications, Télécommunications, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Electronique, Electronics, Circuits électriques, optiques et optoélectroniques, Electric, optical and optoelectronic circuits, Propriétés des circuits, Circuit properties, Circuits optiques et optoélectroniques, Optical and optoelectronic circuits, Optoélectronique intégrée. Circuits optoélectroniques, Integrated optoelectronics. Optoelectronic circuits, Circuit intégré monolithique, Monolithic integrated circuit, Circuito integrado monolítico, Commutateur optique, Optical switch, Conmutador óptico, Contact ohmique, Ohmic contact, Contacto óhmico, Diode MESA, MESA diode, Diodo MESA, Dispositif semiconducteur, Semiconductor device, Dispositivo semiconductor, Evaluation performance, Performance evaluation, Evaluación prestación, Film polymère, Polymer films, Guide onde optique, Optical waveguide, Guía onda óptica, Modulateur électroabsorption, Electroabsorption modulator, Modulador electroabsorción, Optique intégrée, Integrated optics, Optica integrada, Optoélectronique intégrée, Integrated optoelectronics, Optoelectrónica integrada, Passivation, Pasivación, Planarisation, Planarization, Planarización, Réseau optique, Optical arrays, Résistance contact, Contact resistance, Resistencia contacto, Semiconducteur III-V, III-V semiconductors, Technologie autoalignée, Self aligned technology, Tecnología rejilla autoalineada, Tension amorçage, Breakdown voltage, Voltaje perforación, Traitement surface, Surface treatment, and Tratamiento superficie

III-V semiconductor devices typically use structures grown layer-by-layer and require passivation of sidewalls by vertical etching to reduce leakage current. The passivation is conventionally achieved by sealing the sidewalls using polymer and the polymer needs to be planarized by polymer etch-back method to device top for metal interconnection. It is very challenging to achieve perfect planarization needed for sidewalls of all the device layers including the top layer to be completely sealed. We introduce a novel hard-mask-assisted self-aligned planarization process that allows the polymer in 1-3 pm vicinity of the devices to be planarized perfectly to the top of devices. The hard-mask-assisted process also allows self-aligned via formation for metal interconnection to device top of μm size. The hard mask is removed to expose a very clean device top surface for depositing metals for low ohmic contact resistance metal interconnection. The process is robust because it is insensitive to device height difference, spin-on polymer thickness variation, and polymer etch non-uniformity. We have demonstrated high yield fabrication of monolithically integrated optical switch arrays with mesa diodes and waveguide electroabsorption modulators on InP substrate with yield > 90%, high breakdown voltage of > 15 Volts, and low ohmic contact resistance of 10-20 Ω.

Electronics, Electronique, Mechanics acoustics, Mécanique et acoustique, Metrology and instrumentation, Métrologie et instrumentation, Optics, Optique, Physics, Physique, Telecommunications, Télécommunications, 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 solides, Solid mechanics, Mécanique des structures et des milieux continus, Structural and continuum mechanics, Méthodes de mesure et d'essai, Measurement and testing methods, Arbre transmission, Shaft, Arbol transmisión, Effet Doppler, Doppler effect, Efecto Doppler, Interféromètre laser, Laser interferometer, Interferómetro laser, Interférométrie optique, Optical interferometry, Interferometría óptica, Interférométrie speckle, Speckle interferometry, Interferometría speckle, Laser, Láser, Mesure niveau, Level measurement, Medición nivel, Mesure optique, Optical measurement, Medida óptica, Modulation amplitude, Amplitude modulation, Modulación amplitud, Modulation phase, Phase modulation, Modulación fase, Méthode numérique, Numerical method, Método numérico, Niveau bruit, Noise level, Nivel ruido, Numérisation, Digitizing, Numerización, Pistage, Tracking, Rastreo, Source sonore, Sound source, Fuente sonora, Traitement surface, Surface treatment, Tratamiento superficie, Vibromètre, Vibrometer, and Vibrómetro

This paper begins with a review of the fundamental mechanism by which speckle noise is generated in Laser Vibrometry before describing a new numerical simulation of speckle behaviour for prediction of noise level in a real measurement. The simulation data provides real insight into the phase and amplitude modulation of the Doppler signal as a result of speckle changes. The paper also includes experimental data looking at the influence of speckle noise in measurements on rotors with a selection of surface treatments and in scanning and tracking configurations.