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About This Technology

Industry continuously strives to make products that are smaller and lighter and are lower in cost, yet have increased functionality. Microelectromechanical systems, or MEMS, are a class of devices or microsystems produced using micromachining technology, which comprises techniques to make components and devices whose features measure in the tens to hundreds of microns. Initially, scientists borrowed lithography techniques for making two-dimensional integrated circuits from the electronics industry to micromachine simple three-dimensional cavities and freestanding membranes and cantilevers for sensor applications. Not only are microsensors smaller than conventional sensors—a characteristic that allows more functions in the same space, but they can also respond more quickly and more accurately because of the smaller distances in use. Moreover, producing them in large batches is inexpensive. The extension of lithography methods and development of new micromachining techniques have allowed the production of freely moving micromechanical parts.

The biggest market for micromachining is in sensing, from pressure sensors to accelerometers and gyroscopes, but though commercialization first centered on the automotive business, reduced cost has allowed sensors to reach mass consumer markets, creating new interfaces for mobile phones and gaming devices. Demands for mobile devices with small form factor and improved power consumption are also creating a need for new micromachined radio-frequency components and timing devices. Micromachining is in use to create the tiny nozzle arrays in ink-jet printer heads, slider components for hard-disk drives, and micromirror-based projection displays. Micromachining is producing fluidic channels for DNA chips, allowing massive parallelism for high-throughput screening techniques; is reducing some analytical instruments to handheld size; and is creating new types of drug-delivery systems.

Almost every industry is enjoying the benefits of micromachining—particularly the information-technology, telecommunications, automotive, and health-care industries. The relatively low cost of microsensors—$1 to $20 each—will also allow manufacturers to use sensors in many more products than is now possible, including consumer-electronics products, home appliances, toys, and products for home health care. These sensors and other micromechanical devices have begun to incorporate remote powering and wireless communications, allowing remote sensing, connection of home health-care devices to a physician's office, and smart-grid applications. At some time, in the decade leading to 2020, the micromachining industry will contend with nanotechnology. MEMS devices already incorporate nanometer-scale particles and structures as sensor elements, but micromachining processes may also incorporate additional concepts such as molecular manufacturing and self-assembly.