MEMS, or microelectromechanical systems, are integrated systems combining both electrical and mechanical components. They are generally on the micro scale, but may be as large as a few millimeters. The systems are fabricated using integrated circuit (IC) processing technologies. (To view a sample process or a sample structure, refer to either A Typical MEMS Process or MEMS Test Structures.) The mechanical devices typically require more complicated processes than the electrical devices. Thus, there is a constant need for creative processing research in an effort to incorporate both types of components on the same wafer. Since MEMS is a relatively new area of research, there is currently room for a lot of creativity and research effort.

MEMS devices can be used as miniature sensors, controllers, or actuators. But so far, very few commercial applications exist. Some that are presently on the market are pressure sensors and collision detectors (used for air-bag deployment). However, there is a vast amount of research attempting to make these types of MEMS devices available for commercial use:

• Sensors: pressure, chemical, motion, fluid and gas flow.
• Fluid pumps and valves.
• Micro-optics: optical scanners and mirror arrays.

What are the advantages of MEMS devices over current devices that perform the same functions? There are many:

• MEMS devices can be so small that hundreds of them can fit in the same space as one single macro-device that performs the same function.
• Cumbersome electrical components are not needed, since the electronics can be placed directly on the MEMS device. This integration also has the advantage of picking up less electrical noise, thus improving the precision and sensitivity of sensors.
• Using IC processes, hundreds to thousands of these devices can be fabricated on a single wafer. This mass production greatly reduces the price of individual devices. Thus, MEMS devices will be much less expensive than their macro-world counterparts.

For a great many applications, MEMS is sure to be the technology of the future--and is nearly the technology of the present. For more information, visit www.memscenter.com.