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Semi-insulating (100) oriented GaAs was irradiated with 250 keV Xe+ ions with different fluences. The native oxide layers formed in the air after implantation are investigated in this study. The surface density of atoms in the native oxide layer, determined using Rutherford backscattering spectroscopy with nuclear reaction (RBS/NR), increases with ion fluence in the range between 2 × 1013 cm−2 and 8 × 1014 cm−2. Using X-ray photoelectron spectroscopy (XPS) method, the chemical composition was analyzed. It has been found that the native oxide layer on GaAs samples is a mixture of Ga2O3, As2O3, As2O5 and GaAs compounds and the compounds concentration changes depend on ion fluences.

The influence of noble gases ion implantation on the depth distribution of elements in the TiO2/SiO2 bilayers on the Si substrates has been investigated using the Rutherford Backscattering Spectrometry (RBS). The structures were implanted by Ne+, Ar+, Kr+ or Xe+ ions with the energy of 100, 150, 200 or 250 keV. Using the SIMNRA code elemental composition and relative TiO2 and SiO2 as well as TiO2/SiO2 transition layers thicknesses were calculated for different ion species and energies. It was found that the thickness of the transition layers increased after the ion implantation. The effect is evident for Kr+ and Xe+ ions and its magnitude grows with the implanted ion energy. The chemical composition of the near-surface TiO2 layers was determined using the X-ray photoelectron spectroscopy (XPS) method. It was observed that the TiO and Ti2O3 concentrations increase while those of TiO2 and Ti decrease as a function of the implanted ions energy due to atomic displacement during the irradiation process. This effect could be considered as one of the reasons that affects the mixing process at TiO2/SiO2 interfaces induced by ion beam.