PECVD preparation of silicon and germanium with different isotopic composition via their tetrafluorides

18th International Summer School on Vacuum, Electron and Ion Technologies

Sennikov, P.G.^1,2 ; Kornev, R.A.^1 ; Mochalov, L.A.^1 ; Golubev, S.V.^2

Laboratory of Plasma Chemistry, G. G. Devyatykh Institute of Chemistry of High-Purity Substances, Russian Academy of Sciences, 603950 Nizhny Novgorod, Russia^1

Laboratory of Plasma Physics, Institute of Applied Physics, Russian Academy of Sciences, 603950 Nizhny Novgorod, Russia^2

关键词: Chemical mechanism;    Chemical reduction;    Impurities in;    Isotopic composition;    Isotopically enriched;    Physical experiments;    Polycrystalline;    Reduction process;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/514/1/012002/pdf
DOI  :  10.1088/1742-6596/514/1/012002

来源: IOP

【 摘 要 】

Plasma-chemical reduction of silicon and germanium fluorides with different isotopic composition by hydrogen at low pressure was studied experimentally. Samples of silicon of natural isotopic composition and germanium polycrystalline «flakes» with isotopic numbers 72 and 74 were obtained and used to grow poly- and single crystals by the Czochralski method. The contamination by the most important impurities in each type of silicon and germanium was determined. A chemical mechanism for the reduction process was also proposed. It was shown that the direct method of reduction of isotopically-enriched fluorides is suitable for obtaining small amounts of high-purity isotopes of those elements to be used in unique physical experiments.