Microelectromechanical systems (MEMS) are typically constructed on the micrometer scale, with some thin layers being perhaps in the nanometer range. As has already been demonstrated by microelectronic circuits, the lateral dimensions of MEMS are being pushed into the nanometer range as well.
Gary H. Bernstein et al.
This advance has been dubbed “nanoelectromechanical systems,” or NEMS. The ultimate utility of nanomachining (that is to say, the application of capable robots on the molecular scale to solving a range of problems) is limitless.
Such a regime will likely be attainable only by the “bottom-up” approach in which atoms are individually manipulated to construct macromolecules or molecular machines. Properties of pure molecules, such as heat conduction, electrical conduction (low power dissipation), speed of performance and strength, without the limits of boundaries to other molecules and resulting materials defects, vastly exceed those of bulk materials.