| 摘要 |
A process for the treatment of silicon of technical purity is based on solution-crystallization processes in melts of low-melting metals of metallurgical silicon and separated slurry. At the first preliminary stage the treatment of silicon of technical purity from admixtures is carried out at cycling introduction to the surface of melt of low-melting metal of silicon charge of technical purity, the size of which is determined by means of solubility limit of silicon in the melt at this temperature, rapid mixing of solution-melt with the use of pulsed blowing of it by gas mixture based on inert gas, removal of formed slag and crystallization of the purified silicon in a form of ingots for lots of stubs in the process of forced cooling at rotation of solution-melt and the lots of stubs, and in multiple use of same melt of low-melting metal.At the second stage the arrangement on the bottom of crucible of charge of silicon ingots prepared on the first stage is carried out, with limitation of their surfacing, and other low-melting metal at achievement of temperature for the realization of the process the adding to the solution-melt of stub lot, crystallization on them in isothermal conditions of ingots of purified silicon, completion of crystallization by means of cooling of solution-melt in crucible to temperature, at which the solubility of the crystallized material in solution-melt is less than 0.4 %, are carried out. Silicon ingots obtained on the second stage are purified mainly from atoms of low-melting metals, captured on the first two stages by means of crystal pulling by Czochralski method. |
