In this paper, we report the results on the influence of a top oxide layer on the He-cavity formation in silicon samples. Si samples with top oxide layers of different thickness together with the pure silicon (used as reference) were implanted at room temperature with 1 MeV 3He at a dose of 5 × 1016 He/cm2. After implantation, the oxide layer was removed by using HF solution. Cross-sectional transmission electron microscopy (XTEM) was used to study the induced cavities followed by annealing. The results show that He implantation induces a well-defined-damaged layer with a thickness of about 180 nm in the reference Si. The defects are mainly made up of big cavities in the middle of the projected range and a large population of smaller ones both towards the surface and into the bulk. Very few stacking faults and dislocations loops can be seen around this band. The creation of cavities in Si with a 2.3 μm oxide layer, however, is a little different. Regions containing a chain of the biggest cavities surrounded by few smaller ones have also been found. Unexpected results are obtained in Si with a 1.2 μm oxide layer. In this case, only a monolayer of big cavities is observed at the depth corresponding to the projected range. The results are discussed in combination with SIMS measurements and SRIM simulations.

Results of the comprehensive study of deuterium-implanted hexagonal SiC (4H and 6H) using optical absorption and infrared measurements, elastic recoil detection analysis, thermal desorption and positron annihilation spectroscopies are reported. It is shown that implanted deuterium mainly forms bonds with lattice atoms. The amount of deuterium in the form of interstitial molecules and in vacancies is considerably smaller. Ion implantations with fluences exceeding 1015 D+/cm−2 create point defects in concentrations sufficiently high for complete positron trapping. Recrystallisation of the amorphised SiC does not remove the positron traps.

(111) oriented silicon samples were implanted at room temperature with 1.55 MeV 3He ions in the dose range of 5×1015 to 5×1016/cm2. Cross-sectional transmission electron microscopy (XTEM) was used to study the evolution of bubbles and extended defects during subsequent thermal annealing at 800°C and 900°C for 30min. The He desorption from bubbles and bubble precursors was measured by means of nuclear reaction analysis (NRA). TEM observations show that no bubbles were observed in Si implanted at doses lower than 1×1016/cm2, while a well-defined cavity band was formed after implantation at 5×1016/cm2 and subsequent thermal annealing. At the intermediary dose of 2×1016/cm2, however, the evolution of bubbles and extended defects is quite different. The bubbles prefer to nucleate in large planar clusters surrounded by a high density of dislocation loops emerging from them. The clusters of bubbles act as the sources of the dislocation loops. NRA measurements indicate that the He desorption behavior is also dose-dependent. The He desorption is achieved much faster in low dose implanted Si. The results are qualitatively discussed.

4H-SiC samples were implanted at room temperature with 30 keV D+ ions at a dose of 5×1016 D+/cm2. Nuclear reaction analysis (NRA) and secondary ion mass spectroscopy (SIMS) measurements were performed to study the deuterium profiles after subsequent annealing at 1000-1250°C for 10min.Also, analytical techniques: RBS/C and thermal desorption spectroscopy (TDS) were carried out to characterize the evolution of implantation induced defects upon annealing. According to the NRA measurements, no deuterium release was found in the sample annealed at 1000°C. However, increasing the temperature to 1150°C led to a 40% decrease of deuterium content. Similar results about the evolution of D profiles upon annealing have also been obtained by SIMS measurements. In addition, SIMS measurements show that the maximum of the deuterium concentration shifts to the surface. Deuterium desorption at annealing temperatures higher than 1000°C was further confirmed by TDS experiments. Results from RBS/C indicated that during the desorption of deuterium, the implantation induced damage was annealed. These results are discussed.

The chemisorption of cold rolling oil additives on steel and aluminium surfaces is studied with a mass spectrometry technique, ToF-SIMS. Preliminary experiments underline adsorption competition, and thermal threshold for desorption or decomposition. This results fit well with experimental cold rolling results.