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A new method for creating nanomaterials based on gallium oxide by ion-beam synthesis of nanocrystals of this compound in a SiO2/Si dielectric matrix has been proposed. The influence of the order of irradiation with ions of phase-forming elements (gallium and oxygen) on the chemical composition of implanted layers is reported. The separation of gallium profiles in the elemental and oxidized states is shown, even in the absence of post-implantation annealing. As a result of annealing, blue photoluminescence, associated with the recombination of donor–acceptor pairs (DAP) in Ga2O3 nanocrystals, appears in the spectrum. The structural characterization by transmission electron microscopy confirms the formation of β-Ga2O3 nanocrystals. The obtained results open up the possibility of using nanocrystalline gallium oxide inclusions in traditional CMOS technology.

Silicon doped with rare-earth metal erbium is a promising material for the fabrication of highly efficient light emitting structures that can be easily integrated into silicon electronics. The fabrication technology of these structures includes little if any diffusion processes because the efficiency of erbium luminescence in diffusion structures is low. It is still unclear what causes this low erbium luminescence efficiency: low impurity concentration, low optical activity of the luminescence centers or luminescence extinction by the defects. The composition of diffusion silicon layers doped by rare earth erbium has been investigated. The diffusion source was an erbium oxide layer on the surface of the test silicon wafer. The erbium and oxygen distribution profiles in silicon have been measured by SIMS. The concentration of electrically active erbium impurity in the diffusion layers on silicon has been determined by measuring the surface resistance and carrier mobility during consecutive etching of layers. The erbium diffusion coefficient at 1240 °C has been estimated to be 4.8·10–13 cm2·s−1. The concentrations of electrically active (8·1016 cm−3) and total (3·1018 cm−3) erbium in the surface silicon diffusion layers prove to differ noticeably in the presence of high oxygen concentration (>1019 cm−3). A model of erbium and oxygen simultaneous diffusion has been suggested. The model takes into account the association of erbium and oxygen into complexes. The results of numerical simulation and experimental data are in a good agreement for the near-surface region of the diffusion layer.

The distribution of magnetic impurities (Mn) across a GaAs/Zn(Mn)Se heterovalent interface is investigated combining three experimental techniques: Cross-Section Scanning Tunnel Microscopy (X-STM), Atom Probe Tomography (APT), and Secondary Ions Mass Spectroscopy (SIMS). This unique combination allowed us to probe the Mn distribution with excellent sensitivity and sub-nanometer resolution. Our results show that the diffusion of Mn impurities in GaAs is strongly suppressed; conversely, Mn atoms are subject to a substantial redistribution in the ZnSe layer, which is affected by the growth conditions and the presence of an annealing step. These results show that it is possible to fabricate a sharp interface between a magnetic semiconductor (Zn(Mn)Se) and high quality GaAs, with low dopant concentration and good optical properties.