FIELD: technological processes.
SUBSTANCE: invention relates to purification of metallurgical silicon to purity of solar silicon. Essence of the invention consists in melting silicon in a vacuum chamber and adjusting the temperature of the melt, while providing pressure of about 0.0001 bar and maintaining the temperature of the molten silicon in range of 1,400 °C to 1,600 °C. According to method silicon melt is blown by moistened hydrogen, amount of which in mixture H2 and H2O does not exceed range of 200 to 900 moles per 1 mole of water.
EFFECT: simultaneous intensive removal of boron (B) and phosphorus (P) dopant from molten silicon at absence of Si evaporation.
1 cl, 3 dwg
| Title | Year | Author | Number |
|---|---|---|---|
| METHOD OF CLEANING METALLURGICAL SILICON FROM CARBON | 2018 |
|
RU2707053C1 |
| METHOD OF REFINING METALLURGICAL SILICON | 2015 |
|
RU2588627C1 |
| METHOD OF IMPROVING SILICON PURIFICATION EFFICIENCY | 2018 |
|
RU2702173C1 |
| METHOD OF REFINING METALLURGICAL SILICON WITH DRY ARGON PLASMA WITH INJECTION OF WATER ONTO MELT SURFACE WITH SUBSEQUENT DIRECTED CRYSTALLISATION | 2010 |
|
RU2465199C2 |
| METHOD OF PRODUCING POLYCRYSTALLINE SILICON INGOTS | 2011 |
|
RU2465201C1 |
| METHOD OF PURIFYING METALLURGICAL SILICON WITH WET ALTERNATING CURRENT PLASMA IN VACUUM | 2010 |
|
RU2465202C2 |
| SUN-QUALITY SILICON PRODUCTION PROCESS | 2002 |
|
RU2237616C2 |
| METHOD OF PRODUCING HIGH-PURITY SILICON PELLETS | 2011 |
|
RU2477684C1 |
| METHOD OF REFINING METALLURGICAL SILICON | 2011 |
|
RU2465200C1 |
| METHOD OF VACUUM CLEANING OF SILICON | 2008 |
|
RU2381990C1 |
