Self-assembly is a branch of nanotechnology in which objects, devices, and systems form structures without external prodding. Nanotechnology is a field of engineering that deals with design, manufacture, and control on a scale of a few nanometer s (nm) or less, where 1 nm = 10 -9 meters.
In self-assembly, the individual components contain in themselves enough information to build a template for a structure composed of multiple units. An example is the construction of a monolayer, in which a single layer of closely-packed molecules sticks to a surface in an orderly and closely-packed fashion. Self-assembly should not be confused with positional assembly , a technique that has been suggested as a means to build objects, devices, and systems on a molecular scale using automated processes in which the components that carry out the construction process would follow programmed paths.
Nanotechnology has potential benefits for many fields, including water purification, sanitation, agriculture, alternative energy (particularly photovoltaics), home and business construction, computer manufacturing, communications, and medicine.