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O. Yasko et al.
Purity
X-ray phase analysis showed the presence of only polycrystalline silicon in the
deposit. In addition, the electronic microprobe studies and X-ray scattering energy
analysis revealed no impurities. However, levels of Li, Cr, Ni, Fe, Cu, Ag, Mn, Pb,
and Al impurities up to 0.02% were detected by emission spectroscopy method.
The most common impurities are Cu, Fe, Ni, and Ag, but the overall level of their
concentrations would not impact significantly on the performance of solar cells.
Deposits’ purity level was generally over 99.99%.
Specific resistivity
Results of measurements by four-probe method showed disagreement of specific
resistivity values at different places of electrodeposited silicon. At room temperature,
measured resistance of silicon electrodeposited from this system was always greater
than 1 cm.
4 Conclusions
1 From molten LiF-KF-K 2 SiF 6 (8–14 mol%) fluoride electrolytes at 1023 K, silicon
coatings were obtained at graphite substrates.
2 Silicon layer deposited by prolonged electrolysis consists of two parts, namely,
coating with wedge-shaped grains and dendrites.
Competing Interests
Authors of the present paper have no competing interests.
Funding
Authors of the present paper have not used any external sources of funding in addition
to regular financing for scientific investigations provided by CNRS and the University
“Ukraine.”
Authors’ Contributions
Authors of the present paper have made equal contributions in conducting scientific
researches and writing this paper.
Acknowledgements Authors of the present paper acknowledge support of all the Ecole Polytechnique and the University “Ukraine” staff in conducting scientific researches and writing this
paper.
O. Yasko et al.
Purity
X-ray phase analysis showed the presence of only polycrystalline silicon in the
deposit. In addition, the electronic microprobe studies and X-ray scattering energy
analysis revealed no impurities. However, levels of Li, Cr, Ni, Fe, Cu, Ag, Mn, Pb,
and Al impurities up to 0.02% were detected by emission spectroscopy method.
The most common impurities are Cu, Fe, Ni, and Ag, but the overall level of their
concentrations would not impact significantly on the performance of solar cells.
Deposits’ purity level was generally over 99.99%.
Specific resistivity
Results of measurements by four-probe method showed disagreement of specific
resistivity values at different places of electrodeposited silicon. At room temperature,
measured resistance of silicon electrodeposited from this system was always greater
than 1 cm.
4 Conclusions
1 From molten LiF-KF-K 2 SiF 6 (8–14 mol%) fluoride electrolytes at 1023 K, silicon
coatings were obtained at graphite substrates.
2 Silicon layer deposited by prolonged electrolysis consists of two parts, namely,
coating with wedge-shaped grains and dendrites.
Competing Interests
Authors of the present paper have no competing interests.
Funding
Authors of the present paper have not used any external sources of funding in addition
to regular financing for scientific investigations provided by CNRS and the University
“Ukraine.”
Authors’ Contributions
Authors of the present paper have made equal contributions in conducting scientific
researches and writing this paper.
Acknowledgements Authors of the present paper acknowledge support of all the Ecole Polytechnique and the University “Ukraine” staff in conducting scientific researches and writing this
paper.