The results of X-ray photoelectron spectroscopy analysis (core-levels, valence band) and first-principles modelling of bismuth implanted silicon dioxide electronic structure at various Bi-concentrations are reported. Most attention is paid to the study of Bi–O–Si chemical linkages and theoretically derived scenarios of Bi-embedding into SiO2 host-matrix. XPS analytics performed demonstrates the presence of spectral features related both with bismuth-bismuth and pleomorphicaly stretched bismuth-oxygen (Bi/O⋯Si–O) bonds fabrication at lowest employed pulsed-periodical Bi-ion fluence 5 × 1016 cm−2. The latter provides pleomorphic spectral separation of oxygen 2s band into O(I) 2s and O(II) 2s sub-bands. It was found that bismuth pairs of stoichiometric and nonstoichiometric (interstitial) impurities are responsible for that. Further increase in ion fluence up to 3 × 1017 cm−2 yields, in the main, the growth of α-Bi2O3-like frameworks within the volume of initial amorphous SiO2-host what have been interpreted as an appearance of stoichiometric Bi-impurity pairs. The results obtained well agree with our previous investigations of electronic structure of Bi-doped oxide host-matrices and theoretical MD-Tersoff third-party data. New approach toward modelling realistic process of ion-implantation was proposed and discussed.
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