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p-type silicon MOS structures were irradiated with 23 MeV electrons in vacuum for different durations. Capacitance-voltage (C/V), current-voltage (I/V) and conductance-voltage (G/V) methods were used to investigate the changes in the electrical characteristic of the MOS structures after electron irradiation. Our results show that high-energy electron irradiation generates positive charges in the oxide and at the Si-SiO 2 interface, which are frequency dependent. After electron irradiation, two kinds of interface traps are determined. The traps energy position evaluated by these three independent methods is very close to E v + 0.16 eV and B v + 0.36 eV. As these results are in a very good agreement with our earlier results, obtained by TSC and DLTS methods, the observed traps can be attributed to the boron- (V/B) and oxygen (V/O) vacancies complexes.

The influence of high-energy electron irradiation on the redistribution of silicon and oxygen atoms in implanted Si-SiO 2 structures has been investigated by Rutherford backscattering spectroscopy (RBS). Two groups of Si-SiO 2 samples implanted with different doses of silicon ions (1 × 10 12 cm -2 and 1 × 10 16 cm -2 ) are used. The ion energy of 15 keV is chosen to produce maximum radiation defects at the Si-SiO 2 interface. The structures are then irradiated with 20 MeV electrons for different durations (from 60 s up to 120 min). After electron irradiation, the redistribution of the oxygen and silicon atoms in the samples implanted with 1 × 10 12 cm -2 Si + ions is negligible: significant redistribution of these atoms is found only in Si-SiO 2 samples implanted a with dose of 10 16 cm -2 . These results demonstrate that the structural changes at the silicon surface of implanted Si-SiO 2 samples, which take place after electron irradiation, depend more strongly on the implantation dose than on the electron dose irradiation.

The results on the synthesis of new superheavy elements, synthesized in complete fusion reactions of 48Ca ions with actinide targets, are summarized and analyzed. The perspectives for the synthesis of element 117, as well as of elements with Z⩾118 are also considered.