Implantation of radioactive isotopes and the subsequent 2D-detection of the emitted channeled electrons, enables the accurate determination of the lattice location of impurities in single crystalline materials. Recently in KUL, the optical dopant Er, the transition metals Fe, Cu and Ag and the electrical dopant In have been observed on the unexpected bond-centered site in germanium for the first time. Corroborated by density functional calculations, this experimental observation of impurities on the bond-centered site has been attributed to impurity-vacancy complexes, in the so-called split-vacancy configuration.
We apply real-time Rutherford backscattering spectrometry (RBS) to study the growth kinetics of thin films, investigate the dominating diffusing species during phase formation and contemplate the erratic redistribution of impurities in a solid phase reaction. Figure shows an example of the Pt redistribution during Ni(Pt) silicide formation for which real-time RBS is the ideal probe technique thanks to the high sensitivity to high-Z impurities (Pt) and the well separated signals. A tremendous progress in real- time RBS has recently be achieved by the application of artificial neural networks for the data analysis.