3. Manufacture of nanostructured devices

The miniaturization of electronic devices can be achieved by evolving the techniques used up to now (lithography, etching, etc.) to produce ever-smaller patterns from a single crystal of silicon (or another semiconductor). The procedure, which corresponds to a modification of these techniques with a reduction in scale, is known as top-down. Below a certain size, the procedure can no longer be pursued, and a different path must be followed, known as bottom-up, where objects are built by deposition and organized assembly of atoms or aggregates.