METHOD OF PRODUCING HIGHLY PURE HIGHLY-ENRICHED SILICON-28 ISOTOPE Russian patent published in 2019 - IPC B01D59/20 

FIELD: physics.

SUBSTANCE: invention relates to separation of isotopes, in particular to a method of producing silicon-28 isotope, which can be used in microelectronics, fundamental scientific research and other fields. Method is carried out in cascade of gas centrifuges during three stages of separation, at the first stage preliminary enrichment is performed to obtain SiF₄, enriched in silicon-28 to 99,9 % and relative concentration of silicon-29 to silicon-30 of not less than 5, at the second step, the SiF₄ obtained at the first step is purified from silicon-containing complexes, impurities of carbon and oxygen and preliminary treatment of inner surfaces of cascade and vessels for collection of working substance using SiF₄ with high concentration of silicon-28 isotope, third step increases concentration of silicon-28 to value of 99,999 %.

EFFECT: invention provides expansion of technological capabilities of gas centrifugal separation method of isotopes, loss of valuable silicon-28 isotope and obtaining highly pure highly enriched silicon-28 isotope with concentration of 99,999 %, relative concentration of silicon-29 to silicon-30 of not less than 5, concentration of carbon and oxygen impurities of less than 1⋅10^-15 atoms/cm³.

1 cl, 1 dwg