Jet mill producing fine silicon powder
US7789331B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 24, 2007 |
| Grant date | Sep 7, 2010 |
| Priority date | — |
| Expiry date | Dec 23, 2027 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB02C19/061
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A method of jet milling silicon powder in which silicon pellets are fed into a jet mill producing a gas vortex in which the pellets are entrained and pulverized by collisions with each other or walls of the milling chamber. The chamber walls are advantageously formed of high-purity silicon as are other parts contacting the unground pellets or ground powder. The pellets and chamber parts may be formed of electronic grade silicon but polycrystalline silicon may be used for chamber parts. Additionally, the particle feed tube in which the particles are entrained in a gas flow and the vortex finder operating as the outlet at the center of the vortex may be formed of silicon. The milling and feed gas may be nitrogen supplied from a liquid-nitrogen tank lined with stainless steel. The feed pellets may be formed by chemical vapor deposition.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.