Microelectromechanics

As physical structures used in technological applications have been reduced in size, there has been an increasing need to understand the limiting processes of adhesion and to try to minimize them. For example, adhesion due to humidity is known to have a major effect on the durabihty and friction forces experienced at the recording head/disk interface. Microelectromechanical systems (MEMS) are also detrimentally affected by nanoscale adhesion, with their motion being perturbed or prevented. 

B. Ziaie, J.A. von Arx, M.R. Dokmeci, and K. Najafi, A hermetic glass-silicon micropackage with high-density on-chip feedthroughs for sensors and actuators. J. Microelectromechan. Sys. 5, 66—177 (1996). 

A wide variety of solid-state sensors based on hydrogen-specific palladium, metal oxide semiconductor (MOS), CB, electrochemical, and surface acoustic wave (SAW) technology are used in the industry for several years. Microelectromechanical systems (MEMS), and nanotechnology-based devices for the measurement of hydrogen are the recent developments. These developments are mainly driven by the demands of the fuel cell industry. Solid-state approaches are gaining rapid popularity within the industry due to their low cost, low maintenance, replacements, and flexibility of multiple installations with minimal labor. 

Liu, J.-F. Nistorica, C. Gory, I. Skidmore, G. Mantiziba, F. M. Gnade, B. E. 2005. Layer-by-layer deposition of zirconium oxide films from aqueous solutions for friction reduction in silicon-based microelectromechanical system devices. 

Fuller, S. Wilhelm, E. Jacobson, J. 2002. Ink-jet printed nanoparticle microelec-tromechanical systems. J. Microelectromechanical Systems 11 54-60. 

Rogers, J. A. Jackman, R. J. Whitesides, G. M. 1997. Constructing single- and multiple-helical microcoils and characterizing their performance as components of microinductors and microelectromagnets. /. Microelectromechan. Sys. 6 184-192. 

The high selectivity of wet etchants for different materials, e.g. Al, Si, SiOz and Si3N4, is indispensable in semiconductor manufacturing today. The combination of photolithographic patterning and anisotropic as well as isotropic etching of silicon led to a multitude of applications in the fabrication of microelectromechanical systems (MEMS). 

Despite the fact that dry etching techniques have improved dramatically in recent decades, the manufacture of microelectromechanical systems (MEMS) is still a domain of wet etching and silicon electrochemistry. The multiplicity of structures that can be achieved with silicon, together with its excellent mechanical properties [Pe6], have led to an immense variety of micromechanical applications. 

M. von Arx, O. Paul, and H. Baltes. Process-dependent thin-film thermal conductivities of thermal CMOS MEMS , Journal of Microelectromechanical Systems 9, (2000), 136-145. 

D. Gibson, H. Carter, and C. Pm-dy. The Use of Hardware Description Languages in the Development of Microelectromechanical Systems , Analog Integrated Circuits and Signal Processing 28 (2001), 173-180. 

LIGA lithographie, galvanoformung, abformtechnik LTCC low-temperature co-fired ceramics MEMS microelectromechanical systems... 

The industrial movement has been bolstered by two decades of advances in materials science, electronics, and chemometrics. Since the inception of CPAC, the pace of innovation in sensors, instrumentation, and analytics has quickened dramatically. The development of more robust, sensitive photodetector materials, microelectromechanical systems (MEMSs), and fiber optics and the perpetual advancement of computing power (as predicted by Moore s law) have both increased the performance and reduced the cost of . As a result, is now a critical part of routine operations within the realm of industrial chemistry. Many general reviews on the subject of (and PAT) have been published [6—10]. A series of literature reviews on the subject of have been published regularly in Analytical Chemistry. 

Scientists can fabricate microelectromechanical devices such as the cantilever above, which is a beam of silicon anchored at one end. The beam has a resonant vibrational frequency near 13 X 106 hertz (13 MHz) when stimulated with a piezoelectric vibrator. (A piezoelectric crystal, such as quartz, is one whose dimensions change in response to an electric field.) When 93 attograms (93 X 10, 8g) of an organic compound bind to the gold dot near the end of the cantilever, the vibrational frequency decreases by 3.5 kHz because of the extra mass on the beam. The minimum mass that can be detected is estimated as 0.4 attogram. 

S.A. Soper, S.M. Ford, S. Qi, R.L. McCarley, K. Kelly and M.C. Murphy, Polymeric microelectromechanical systems, Anal. Chem., 72 (2000) 643A-651A. 

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