nano electro mechanical system (NEMS)
Nano Electro Mechanical Systems (NEMS) are a combination of mechanical and optical elements as well as sensors, actuators and electronic circuits on a substrate or chip. They are a further development of Micro Electro Mechanical Systems( MEMS) on the nano level, to which they are similar in structure and application.
For the production of NEMS and MEMS, semiconductor materials or deformable plastics are provided with a coating. The photoresist often used for this purpose is used to transfer structures lithographically in a further step. Compared to semiconductors, these are strongly structured substrates with deep structures in the nanoscale.
Micro Electro Mechanical System (MEMS) and Nano Electro Mechanical System (NEMS) can also be defined as micro- and macro-electronic circuits that have the ability to decide and react through integrated sensor technology. The structures of NEMS are approached through two approaches: In top-down technology, specially designed tools are used to produce even smaller tools - in effect, one moves from the millimeter (mm) to the micrometer (µm) to the nanometer (nm) range. In the bottom-up method, individual atoms or molecules are combined to form complex functional units.
In 2000, the first very large scale integration NEMS ( VLSI-NEMS) was introduced. This uses Atomic Force Microscope ( AFM) tips to heat or scan a deformable substrate so that it acts like a memory. Atomic Force Microscope (AFM) is the term used to describe atomic force microscopy. Here, a needle tip is passed over the surface of an object and a laser beam is directed at the object. With this technology, resolutions in the sub-angstrom range are possible. One angstrom corresponds to 0.1 nm as a unit of length.
An example of top-down technology is the nanomotor. This is built from tiny nanotubes of carbon (carbon nanotubes) and converts electrical energy into thermal energy, which in turn is then converted into kinetic energy. Such nanomachines can be used as nanosyringes or actuators.
MEMS and NEMS are becoming increasingly important in information technology, medical technology, biotechnology, and aerospace. In aerospace they are used as microactuators, microsensors and nanosensors; in automotive technology as signal converters and acceleration sensors. The use of intelligent microrobots will increase through further miniaturization to NEMS.