ABSTRACT
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 ß-Ga2O3 nanocrystals. The obtained results open up the possibility of using nanocrystalline gallium oxide inclusions in traditional CMOS technology.
ABSTRACT
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.
