The Ion Implanter Facility has trained numerous research students from several institutions, as well as providing many undergraduate research projects. Existing modifications have made it a versatile machine with many more years of potential exploitation. Anticipated modifications and enhancements will greatly increase its potential as an excellent nanoscale research tool, and an increasing throughput of postgraduate students is expected. The rapidly growing research field of nanotechnology will be well served by this facility.
The Ion Implantation and Nanotechnology Research Activities at TAMS.
The modifications to the structural and optical properties of a variety of materials are analysed by optical methods including optical absorption, photo-luminescence and thermo-luminescence, Raman and Brillouin light scattering spectroscopy. Rutherford Back Scattering (RBS) and Elastic Recoil Detection Analysis (ERDA) have also been used in appropriate instances. Collaborative work will be continued along these lines over the next five years, involving other materials of interest, the equipment listed above, and students from previously disadvantaged communities. Projects of this type have yielded numerous publications in the past.
The refurbishment of the ion implanter facility anticipates increased frequency of research papers and the concomitant throughput of MSc and PhD students from a wider selection of universities than has been the case in the past.
A lot of interesting high-energy implantation work has been carried out internationally. This can be done to some extent on the 6 MV van der Graaf Tandem Accellerator but with small beam currents (giving low doses or small implanted areas or long implantation times). Accordingly, the future acquisition of a versatile high-energy implantation accelerator will be appropriate. This will enable implantation at higher ion energies for some applications, so as to modify materials to greater depths. Currently, the 1.4 MeV Cockcroft-Walton is capable of carrying out the implantation of H and He ions in a scanning mode, and has already been used for many continuing and anticipated studies. Further and more wide-ranging collaborations are being sought from researchers at other universities within South Africa.
The following Ions can be implanted in solid state materials, and at any energy up to 170 keV. These are H+, He+, Li+, B+, C+, N+, O+, F+, Ne+, Na+, Mg+, Al+, Si+, P+, Cl+, K+, Ar+, Ca+, Sc+, Ti+, V+, Cr+, Mn+, Fe+, Co+, Cu+, Zn+, As+, Se+, Br+, Kr+, Mo+, Pd+, Ag+, In+, Sn+, I+, Xe+, W+, Pd+, Bi+, U++. Electrostatic deflection plates are used to scan the beam across the sample surface in order to achieve uniformity. The implanted dose ranges from 1010 ions/cm2 up to a maximum of 1018 ions/cm2.