Composition and electronic structure of hidden nanoscale phases and layers of BaSi-=SUB=-2-=/SUB=- formed in the near-surface of Si
Аннотация
For the first time, nanoscale phases and layers of BaSi 2 were obtained by implantation of Ba + ions with an energy of E 0 =20-30 keV in the surface layer of Si(111). In particular, it is shown that at a dose of D~10 15 cm -2 nanophases with a band gap E g ~0.85 eV are formed, and at D~10 17 cm -2 a BaSi 2 nanolayer with E g =0.67 eV. The composition and structure of the barium disilicide nanostructure were investigated by light absorption spectroscopy by Auger electron spectroscopy, and the X-ray surface morphology was studied by scanning electron microscopy. The optimal modes of ion implantation and annealing for obtaining nanoscale phases and layers of BaSi 2 in the near-surface region of Si have been established. Using the method of light absorption spectroscopy, the band gap and the degree of coverage of the layer with BaSi 2 nanophases were estimated. It has been shown that at a dose of D≥6·10 16 cm -2 the nanolayer of BaSi 2 . Keywords: ion implantation, nanostructure, nanophase, annealing, barium disilicide, Auger electrons, degree of coverage.