It is investigated the formation of the phase composition and structure in the nanoscaled CoSbx (30 nm) (1.82 ≤ x ≤ 4.16) films deposited by the method of molecular-beam epitaxy on the substrates of the oxidated monocrystalline silicon at 200°C and following thermal treatment in vacuum in temperature range of 300–700°C. It is established that the films after the deposition are polycrystalline without texture. With increase in Sb content the formation of the phase composition in the films takes place in such sequence as this is provided by phase diagram for the bulky state of the Co–Sb system. At annealing in vacuum at temperature above 450–500°C a sublimation not only of the crystalline Sb phase but from the antimonides occurs. This is reflected on the phase composition change by following chemical reactions: \( {\mathrm{CoSb}}_2\overset{600{}^{\circ}\mathrm{C}}{\to}\mathrm{S}\mathrm{b}\uparrow =\mathrm{CoSb},{\mathrm{CoSb}}_3\overset{600{}^{\circ}\mathrm{C}}{\to}\mathrm{S}\mathrm{b}\uparrow ={\mathrm{CoSb}}_2,{\mathrm{CoSb}}_3+\mathrm{S}\mathrm{b}\uparrow \overset{600{}^{\circ}\mathrm{C}}{\to }{\mathrm{CoSb}}_3 \) and leads to increase in amount of the CoSb and CoSb2 phases and decrease in amount of the CoSb3. CoSbx (30 nm) (1.8 < x < 4.16) films under investigation are thermostable up to ~350°C.
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Acknowledgments
The authors would like to thank Prof. M. Albrecht, Dr. G. Beddies, PhD M. Daniel, and workers from Chemnitz University of Technology (Germany) for sample preparation, assistance in conduction of investigations and discussion of results.
This work was financially supported by the Deutsche Akademischer Austauschdienst (DAAD) in the frame of the Leonard-Euler-Program (Grant N 50744282).
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Published in Poroshkovaya Metallurgiya, Vol. 54, Nos. 11–12 (506), pp. 130–138, 2015.
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Shkarban, R.A., Peresunko, Y.S., Pavlova, E.P. et al. Thermally Activated Processes of the Phase Composition and Structure Formation of the Nanoscaled Co–Sb Films. Powder Metall Met Ceram 54, 738–745 (2016). https://doi.org/10.1007/s11106-016-9769-0
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DOI: https://doi.org/10.1007/s11106-016-9769-0