If the typical dimensions of a solid shrinks to a few nanometers its properties differ from macroscopic ones. The nanostructure can be a thin layer, a wire or an ensemble of tiny precipitates, i.e. 2-, 1- or 0-dimensional objects. Besides their new properties, nanostructures differ also with the typical reaction pathways of their synthesis from macroscopic objects. Here, the ion beam technique is due to its cleanness, very good controllability, and its extreme nonequilibrium feature a unique tool for the synthesis of nanostructures, especially for electronic, optoelectronic but also pure optical applications.
Functional nanostructures for electronic and optical applications are fabricated by means of accelerated ions. For this aim,
- using focused ion beams nanostructures are “written” into surfaces.
- large-area ion implantation or ion irradiation are performed to form Nanostructures by subsequent self-organisation during phase separation and interface area minimization.
- by steady-state ion irradiation, surfaces and interfaces are driven far from equilibrium where new physical properties and pattern formation can be found.
- pre-patterned wafers (e.g. by lithography) are doped by ion implantation to fabricate devices for nanotechnology.
The excellent collaboration between theory and experiment is the strong point of this topic. The ion-beam-assisted synthesis of nanostructures is investigated
- using an unique manifold of ion beam equipment (100 eV...50 MeV) and semiconductor processing techniques in the clean room as well as different characterisation methods.
- by process modelling, computer code development, atomistic computer simulations and analytical treatments.