Microscale device technology

Other advantages of microfabricated devices include faster response times, and the fabrication of multiple test sites for simultaneous replicate assays in one microfabricated device. This analytical redundancy provides a safeguard that is not easily attained in a conventional macroscale analyzer, where duplicate assays represent the usual extent of repetitive assay of a sample. Encapsulation technology used in the microelectronics industry may also be applicable to microscale devices and could be extended to operations over a wide range of environmental conditions of humidity, and temperature. 

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Fuel cells are electrochemical devices that convert the chemical energy of the fuels directly into electrical energy, and are considered to be the key technology for power generation in stationary, automotive, portable and even microscale systems. Among all kinds of fuel cells, direct methanol fuel cells have really exhibited the potential to replace current portable power sources and micropower sources in the market (Yao et al., 2006). 

Historically, silicon and silicon based materials have formed the basis for the well-established integrated circuit (IC) technology. As a consequence, polycrystalline silicon (polysilicon) is one of the most commonly used structural materials for MEMS. Comparatively, silicon is a good structural material for the microscale. However, the inherent mechanical nature of MEMS devices brings about a new level of complexity to their production and reliability compared to standard integrated circuits. Micromechanical structures can be... 

If renamed today, microelectronics would be called nanoelectronics since sizes have been pushed well below 1 p.m. The fabrication of modern electronic devices, such as large-scale integrated circuits, involves an elaborate sequence of physical and chemical operations. As the size scale becomes smaller, it is increasingly necessary to recognize the molecular nature of matter. This and the next sections describe technology applicable to the microscale that is somewhat less than state-of-the art. 

Section IV then tackles the most recent trend in analytical instrumentation, which is miniaturisation and the drive to create lab-on-a-chip devices. In this section, 1 discuss the development of chip-based technologies and the challenges associated with this such as pumping fluids on the microscale, fitting components onto a chip, detection strategies and how processes such as mixing are so different in the microworld when compared to the macroworld. 

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