MicroElectoMechanical Systems (wiki). Yep, these little suckers are going to be big one day, so to speak. I found a page full of examples of gears, racks, mirrors, shutters and drive trains all in beautiful electron microscope vision.
What is it? Well, Wikipedia has this to say about them and quite frankly it does a good job:
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.
I do know that there are some of these wonderful devices in the new Nintendo Wii (shameless plug, can’t fault a man for trying to get some extra cash can you?).
(image Courtesy of Sandia National Laboratories, SUMMiTTM Technologies, www.mems.sandia.gov)
Sandia MEMS: Image Gallery