Micro electrical mechanical systems MEMS

In the last couple of decades, both Micro-electro-mechanical systems (MEMS) and microbiology achieved remarkable progress. MEMS provide very small systems, made of very small electrical and mechanical components. These systems range in size from sub micrometer level to millimeter level, and can include any component number, from a few to millions, in a particular system. MEMS extend the fabrication... 

Developments in measurement science have been largely influenced by advances in the technical fields driven by needs in the military, communication, and the computer related industries. These developments have resulted in improvements in techniques for miniaturization, as reflected in MEMS (micro-electrical mechanical systems) technology. 

Micro-electro-mechanical systems (MEMS) Chip-level systems based on silicon devices on the order of 100 /u-m and smaller that combine electrical and mechanical functions. MEMS devices are used to implement chip-level motors capable of moving such optical devices as micromirrors, gratings, lenses, and shutters. 

Kawano R, Osaki T, Takeuchi S. A parylene nanopore for stable planar lipid bilayer membranes. In IEEE 23rd international conference on micro electro mechanical systems (MEMS) 2010. Wanchai, Hong Kong Institute of Electrical and Electronics Engineers 2010. p. 923-6. ISBN 978-1-4244-5761-8. 

Chen, R., H. Nguyen, and M. C. Wu. 1999. A low-voltage micromachined optical switch by stress-induced bending. Pp. 424-428 in Proceedings of the IEEE 12 International Workshop on Micro Electro Mechanical Systems (MEMS 99), Orlando, Ha., January 17-21, 1999. New York Institute of Electrical and Electronics Engineers. 

Liu and coworkers have been also designed and successfully realized a novel micro-electro-mechanical-systems (MEMS) based polymer drug dehvery microsystem. The device consists of an array of metallic contacts, able to create an uniform electric field. In particular, a hydrogel polymer matrix loaded with hematoxylin dye, as model of hydrophilic drug, has been smdied. The dehvery microsystem operated at normal body temperature (37 °C) under an applied voltage of 20 V. The release rate and dose were accurately controlled. The polymer responds to the electrical stimulus by shrinking and releases the hematoxylin dye into solution. The release of hematoxylin in the media was monitored using ultraviolet-visible spectrophotometry. 

Almost all types of sensors can be attached to such a sensor node as long as the power consumption is in relation to the purpose of the sensing system. Low-power sensors are first choice and that is the reason why micro-sensors called MEMS (micro electro-mechanical systems) are very attractive to be combined with such a system. MEMS are small integrated devices combining electrical and mechanical components that could be produced for about 50 each. Because the process elements and internal linkage movements are now small, these MEMS-based transducers consume very little power. The low cost, low power and small size of MEMS-based transducers have revolutionized the way we can measure. This includes also the combination of sensor data and the formation of networks of sensors as well as combination with low power video techniques (VSLI cameras). 

Historically microfabrication techniques have first been developed to meet the requirements of microelectronics, but they also have allowed the emergence and the development of a new research field where mechanical elementscan be manufactured and actuated with electrical signals at a micro- and even nanometer scale. To describe this emerging research field, R. T. Howe and others proposed the expression Micro Electro Mechanical Systems or MEMS in the late 1980 s [14]. MEMS is not the only term used to describe this field which is also called as micromachines, for instance in Japan, or more broadly referenced as microsystem technology (MST) in Europe. 

Hot-wire anemometers ( micro/nano anemometers) have been developed for a wide spectrum of applications from experimental fluid mechanics to aerospace engineering to measure physical parameters such as temperature, flow rates, and shear stress. The advent of microelectromechan-ical systems (MEMS) and nanoscale thermal sensors has provided an entry point to microfluidics, biomedical sciences, and micro-circulation in cardiovascular medicine. These MEMS and nanoscale devices are fabricated with semiconductor-based sensing elements which harbor the physical property of a resistor and have the dimension of one-tenth of a strand of hair. On the basis of the heat transfer principle, these resistant elements are heated by the Joule effect due to the passage of electric current. As the... 

The piezoelectric biosensor is a class of micro electromechanical systems (MEMS) based on the principle of measurement of changes in oscillating crystal resonance frequency due to bioreceptor and analyte interactions. In piezoelectric MEMS biosensors, the transducer is made of piezoelectric material (hke quartz) and the biosensing material is then coated on the piezoelectric material, which vibrates at the natural frequency. Piezoelectric materials have no center of symmetry and produce an electric signal when stressed mechanically (i.e., by applying some pressure on them). A crystal oscillates at a certain... 

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