Purification and deposition of silicon by an iodide disproportionation reaction
US6468886B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 28, 2001 |
| Grant date | Oct 22, 2002 |
| Priority date | — |
| Expiry date | Aug 28, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/28525
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
Method and apparatus for producing purified bulk silicon from highly impure metallurgical-grade silicon source material at atmospheric pressure. Method involves: (1) initially reacting iodine and metallurgical-grade silicon to create silicon tetraiodide and impurity iodide byproducts in a cold-wall reactor chamber; (2) isolating silicon tetraiodide from the impurity iodide byproducts and purifying it by distillation in a distillation chamber; and (3) transferring the purified silicon tetraiodide back to the cold-wall reactor chamber, reacting it with additional iodine and metallurgical-grade silicon to produce silicon diiodide and depositing the silicon diiodide onto a substrate within the cold-wall reactor chamber. The two chambers are at atmospheric pressure and the system is open to allow the introduction of additional source material and to remove and replace finished substrates.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.