Microelectromechanical Systems (MEMS) is the technology of the very small, and merges at the nanoscale into "Nanoelectromechanical" Systems (NEMS) and Nanotechnology.
MEMS are also referred to as micromechanics, micro machines, or Micro Systems Technology (MST). MEMS are separate and distinct from the hypothetical vision of Molecular nanotechnology or Molecular Electronics.
MEMS generally range in size from a micrometer (a millionth of a meter) to a millimeter (thousandth of a meter). At these size scales, the standard constructs of classical physics do not always hold true. Due to MEMS' large surface area to volume ratio, surface effects such as electrostatics and wetting dominate volume effects such as inertia or thermal mass.
They are fabricated using modified semiconductor fabrication technology (used to make electronics), molding and plating, wet etching (KOH, TMAH) and dry etching (RIE and DRIE), electro discharge machining (EDM), and other technologies capable of manufacturing very small devices.
Companies with strong MEMS programs come in many sizes. The larger firms specialize in manufacturing high volume inexpensive components or packaged solutions for end markets such as automobiles, biomedical, and electronics. The successful small firms provide value in innovative solutions and absorb the expense of custom fabrication with high sales margins. In addition, both large and small companies work in R&D to explore MEMS technology. Complexity and performance of advanced MEMS based sensors are described by different MEMS sensor generations.
