Добірка наукової літератури з теми "CMOS micro-Nanotechnology"

AbstractThis paper discusses some of the highly interesting effects that occur when photons interact with carbon nanotubes. From position dependent photoconductivity of nanotube thin films to photon induced elastic actuation of carbon nanotubes is presented. A new field of micro-opto-mechanical systems (MOMS) is envisioned through the miniaturization of nanotube actuators using MEMS and CMOS processes. Number of remotely controlled MOMS devices including MOMS grippers, MOMS cantilevers and MOMS mirrors are presented. The performance of these devices rivals their MEMS electrostatic counterparts while consuming only fraction of energy and enabling remote controllability. Finally, the interaction of light with nanotubes for biomedical nanotechnology and photodynamic cancer therapy is presented.

L’essor considérable des applications liées aux récents progrès de l’internet des objets (IoT) nécessite de développer de nouvelles solutions de collecte de l’énergie environnante pour alimenter les microsystèmes. L’abondance de la chaleur dans notre environnement permet aux dispositifs de récupération de l’énergie thermique d’être une des solutions. Dans ce travail, nous avons développé une famille de micro-générateurs thermoélectriques planaires (µTEG), intégrant une topologie originale de thermopile en 2.5D périodiquement repliée et distribuée sur multi-membrane, capable de convertir de manière directe la chaleur en énergie électrique utile. Cette thermopile, à grande densité d’intégration, emploie des thermocouples à base de matériaux thermoélectriques métalliques (Chromel et Constantan), associés électriquement soit en série, soit en parallèle, permettant de réduire drastiquement la résistance électrique interne de ces µTEGs, à quelques dizaines de Ohms. Pour obtenir de ces modules une puissance de sortie maximale, des modélisations numériques 3D sous COMSOL Multiphysics®, au niveau thermique, ont permis d’optimiser leur dimensionnement. La fabrication de ces dispositifs a été réalisée par des procédés compatibles CMOS, à faible coût, utilisant des matériaux non polluants, abondants, et respectueux de l’environnement. Elle a employé la technique de gravure profonde DRIE de wafers de Silicium pour libérer des membranes de longueurs ajustables permettant d’adapter la résistance thermique des µTEGs à leur environnement. Les dispositifs réalisés en centrale de technologie ont été caractérisés à l’aide de bancs de mesure spécifiques développés à cette fin. La récupération d’un Watt de chaleur permet d’atteindre des puissances électriques thermogénérées de quelques centaines de microwatts. Cela classe ces nouveaux µTEG 2.5D parmi les meilleurs µ-modules de l’état de l’art utilisant des thermoélectriques métalliques
The tremendous growth of applications related to recent advances in the Internet of Things (IoT) requires the development of new solutions for harvesting/scavenging the environmental energy to power microsystems. The abundance of heat in our environment allows thermal energy harvesting devices to be one of the solutions. In this work, we have developed a family of planar micro-thermoelectric generators (µTEG), integrating a novel 2.5D thermopile topology periodically folded and distributed on multi-membrane, capable of converting heat directly into useful electrical energy. This thermopile, with high integration density, uses thermocouples based on metallic thermoelectric materials (Chromel and Constantan), electrically associated either in series or in parallel, allowing to reduce drastically the internal electrical resistance of these µTEGs to a few tens of Ohms. A 3D thermal modelling in COMSOL Multiphysics® was used to design the optimal dimensions of the modules so they would deliver the maximum output power. The fabrication of these devices is made by low-cost CMOS-compatible processes, using non-polluting, abundant and environmentally friendly materials. Deep reactive ionic etching (DRIE) of Silicon wafers is used to release membranes with adjustable lengths allowing to adapt the thermal resistance of these µTEGs to their environment. The devices realized in IEMN clean room, have been characterized using specific measurement benches developed for this purpose. The harvesting of one Watt of heat leads to thermo-generated electrical powers of a few hundred microwatts. This ranks these new 2.5D µTEGs among the best state-of-the-art µ-modules using metallic thermoelectrics

Micro-PIV experiments rely upon the use of a microscope to achieve the higher spatial resolution. However, several optical limitations are introduced at these scales [1–3]. In addition, due to the low illumination levels, micro-PIV experiments require the use of either a cooled CCD camera or an image intensifier to provide increased signal-to-noise ratio. Although CCD cameras offer superior sensitivity and signal to noise ratio, intensified CMOS cameras offer an attractive alternative for performing high frequency measurements. However, intensified cameras are known to introduce artifacts such as added background noise. This study examines these issues and the feasibility of employing such technologies for microPIV through the use of the IDT-X5 intensified CMOS camera, capable of 500 Hz at a resolution of 2352×1728 pixels, with pulse separations as low as 2μs.

There is an increasing demand of nanotechnology and nano-devices in microelectronics, optics, biomedical and precision engineering industries. In this context, a wide range of applications require micrometer/nanometer positioning within a long range. Ultra precision manufacturing and inspection systems in micro-automating semiconductor fabrication, nanopositioning and nanomeasuring machines (NPM-Machine), development of MEMS and NEMS, copying machines, stepper stages for photolithography, small-scale measuring machines (CMMs) for large area scanning or surface imaging in scanning probe microscopy (SPM) are a few examples of these applications. In some applications, cryogenic environments (temperatures below 120 K) are a desirable or mandatory condition. The sensitivity of a large number of sensors is greatly increased when they are at cryogenics temperatures, like for example, those required for far infrared interferometer spectroscopy. The operating conditions in these environments include very low temperatures but also high vacuum. In this context, it is challenging for mechanisms to overcome all the tribological problems associated with these conditions. In addition very low energy consumption is also desirable in cryogenic environments. The invention here presented is a contactless linear slider that gets benefit of superconducting magnetic levitation to obtain a nanometer resolution within a long stroke (∼ 15 mm), minimizing run-outs of the slider (in the micron scale). Moreover, due to self-stable levitation and guidance of the slider, the complexity of the control is significantly reduced and the power consumption minimized (of the order of mW). The linear slider can be divided in two subsystems: the guidance system and the actuating system. The guidance system is composed of a static guideline, made of two superconducting disks and a slider composed of a long permanent magnet. Due to the high translational symmetry of the magnetic field generated by the PM, a contactless sliding kinematic pair is established between the PM and the superconductors in the sliding DoF. Thus, the slider is able to be moved in the sliding direction with very low resistance. However, greater restoring forces appear if the PM is moved in any other direction. Due to the lack of contact between the moving parts is also suitable for operation in clean-room applications, like in semiconductor manufacturing industry. Ultimately, the device was designed, built and tested in a relevant cryogenic environment (15 K and high vacuum) and the results introduced and discussed.