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arXiv · 1505.06901

Octahedral conversion of a-SiO2-host matrix by pulsed ion implantation

D. A. Zatsepin·A. F. Zatsepin·D. W. Boukhvalov·E. Z. Kurmaev·N. V. Gavrilov·N. A. Skorikov·A. von Czarnowski·H. -J. Fitting
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Abstract

This is the abstract. The results of measurements of X-ray photoelectron spectra (XPS) of a-SiO2-host material after pulsed implantation with [Mn+] and [Co+, Mn+]-ions as well as DFT-calculations are presented. The low-energy shift is found in XPS Si 2p and O 1s core-levels of single [Mn+] and dual [Co+, Mn+] pulsed ion-implanted a-SiO2 (E = 30 keV, D = 2*10^17 cm^-2) with respect to those of untreated a-SiO2.The similar changes are found in XPS Si 2p and O 1s of stishovite compared to those of quartz. This means that the pulsed ion-implantation induces the local high pressure effect which leads to an appearance of SiO6-structural units in alpha-SiO2 host, forming "stishovite-like" local atomic structure. This process can be described within electronic bonding transition from the four-fold "quartz-like" to six-fold "stishovite-like" high-pressure phase in SiO2 host-matrix. It is found that such octahedral conversion depends on the fluence and starts with doses higher than D = 3*10^16 cm^-2.

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D. A. Zatsepin, A. F. Zatsepin, D. W. Boukhvalov, E. Z. Kurmaev, N. V. Gavrilov, N. A. Skorikov, A. von Czarnowski, H. -J. Fitting. 2015-05-26. Octahedral conversion of a-SiO2-host matrix by pulsed ion implantation. https://doi.org/10.1002/pssb.201552103

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