Method of manufacturing polycrystalline silicon rod
US8328935B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 3, 2009 |
| Grant date | Dec 11, 2012 |
| Priority date | — |
| Expiry date | Nov 20, 2030 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B33/035
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The present invention is a method of manufacturing polycrystalline silicon rods, wherein silicon is deposited onto a silicon core wire by a chemical vapor deposition (CVD) method such that a silicon member, which is cut out from a single-crystalline silicon ingot at an off-angle range of 5 to 40 degrees relative to a crystal habit line of the ingot, is used as the silicon core wire. The single-crystalline silicon ingot is preferably grown by a Czochralski (CZ) method or floating zone (FZ) method, such that the ingot preferably has an interstitial oxygen concentration of 7 ppma to 20 ppma. Silicon rods produced by this method are less likely to suffer a breakage caused by cleavage during the growth process of polycrystalline silicon during CVD, and exhibit improved FZ method success rates. The polycrystalline silicon rods produced by this method also have low impurity contamination and high single-crystallization efficiency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.