Method for producing silicon
US8303796B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | May 25, 2007 |
| Grant date | Nov 6, 2012 |
| Priority date | — |
| Expiry date | Mar 10, 2029 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P70/50
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Disclosed is a novel method for producing high-purity silicon at low cost. Particularly disclosed is a novel method for producing high-purity silicon, which can be suitably used as a raw material for solar cells, at low cost. Specifically, a method for producing silicon wherein silica is subjected to molten salt electrolysis in an electrolysis vessel comprises, in the following order, a step (1) wherein the silicon content in an silicon-containing alloy, which is in a liquid phase at the electrolysis temperature, is increased by using the alloy as the cathode and performing electrolysis; a step (2) wherein the silicon-containing alloy serving as the cathode is taken out of the electrolysis vessel before it reaches the concentration at which silicon begins to precipitate at the electrolysis temperature; a step (3) wherein silicon is solidified by cooling the taken-out silicon-containing alloy within the temperature range higher than the eutectic point but lower than the electrolysis temperature; and a step (4) wherein the solidified silicon is collected.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.