702
M. Dohlus et al.
11.2.3 Ion Accelerators
The structure of condensed matter materials can be modified by adding additional
elements in order to achieve the special behavior required for a specific application.
For this purpose, the application of accelerators is ideal, and enables high selectivity
to be achieved in both the species of atoms to be implanted as well as their
kinetic energy which allows control of the desired composition, including depth
and thickness of the layers.
The application of accelerated ion beams in industry has two main directions,
one for the analysis of materials and the other for the modification and production of materials. A new topic is the use of ion beams in medicine to treat
cancer by irradiation with protons or carbon ions. In contrast to electron beams
the energy transfer of heavy particles is concentrated at low kinetic energies
(Bragg peak) and allows a three dimensional control of the desired cell damage.
11.2.3.1 Materials Modifications
The implantation of atoms into solid structures allows tailored changes in the
properties of materials to be achieved. Targets are metals, semiconductors and
insulators.
Tribological applications like the change of wear and friction are one of the
domains in that field. Particularly the modification of surface hardness, ductility and
lubrication effects are of interest. The implantation of nitrogen into metals and also
alloys producing hardening of the surfaces has improved dramatically the efficiency
of cutting tools.
Magnetic properties of materials have been modified by ion implantation [39].
The ion implantation into ceramics has started another industrial application
[40].
In semiconducting materials, ion implantation is one of the most important processes for producing integrated electronic circuits. Mainly the basic semiconductors
consisting of pure silicon and germanium are doped by elements of the third and fifth
group to produce suitable acceptors and donors for transistor functions. Whereas for
logic devices low energy implantation down to a few eV is important, the production
of high power devices requires ion energies up to several MeV.
The profiles of implanted species are superior to those achieved by previously
used diffusion processes. Ion implantation, however, produces radiation damage
in the sample material which needs an annealing process in every case to produce functional electronic devices. Three dimensional ICs can be produced by
a sequence of implantation and annealing if the necessary insulating layers can
be provided. In many cases these layers are also produced by ion implantation.
M. Dohlus et al.
11.2.3 Ion Accelerators
The structure of condensed matter materials can be modified by adding additional
elements in order to achieve the special behavior required for a specific application.
For this purpose, the application of accelerators is ideal, and enables high selectivity
to be achieved in both the species of atoms to be implanted as well as their
kinetic energy which allows control of the desired composition, including depth
and thickness of the layers.
The application of accelerated ion beams in industry has two main directions,
one for the analysis of materials and the other for the modification and production of materials. A new topic is the use of ion beams in medicine to treat
cancer by irradiation with protons or carbon ions. In contrast to electron beams
the energy transfer of heavy particles is concentrated at low kinetic energies
(Bragg peak) and allows a three dimensional control of the desired cell damage.
11.2.3.1 Materials Modifications
The implantation of atoms into solid structures allows tailored changes in the
properties of materials to be achieved. Targets are metals, semiconductors and
insulators.
Tribological applications like the change of wear and friction are one of the
domains in that field. Particularly the modification of surface hardness, ductility and
lubrication effects are of interest. The implantation of nitrogen into metals and also
alloys producing hardening of the surfaces has improved dramatically the efficiency
of cutting tools.
Magnetic properties of materials have been modified by ion implantation [39].
The ion implantation into ceramics has started another industrial application
[40].
In semiconducting materials, ion implantation is one of the most important processes for producing integrated electronic circuits. Mainly the basic semiconductors
consisting of pure silicon and germanium are doped by elements of the third and fifth
group to produce suitable acceptors and donors for transistor functions. Whereas for
logic devices low energy implantation down to a few eV is important, the production
of high power devices requires ion energies up to several MeV.
The profiles of implanted species are superior to those achieved by previously
used diffusion processes. Ion implantation, however, produces radiation damage
in the sample material which needs an annealing process in every case to produce functional electronic devices. Three dimensional ICs can be produced by
a sequence of implantation and annealing if the necessary insulating layers can
be provided. In many cases these layers are also produced by ion implantation.