On-site ammonia purification for semiconductor manufacture
US6001223A · kind A · utility
13Cited by
30References
9Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 10, 1998 |
| Grant date | Dec 14, 1999 |
| Priority date | — |
| Expiry date | Mar 10, 2018 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01C1/024
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Highly purified ammonia for use in semiconductor manufacturing is prepared on-site by drawing ammonia vapor from a liquid ammonia reservoir, passing the vapor through a filter capable of filtering out particles of less than 0.005 micron in size, and scrubbing the filtered vapor in a high-pH aqueous scrubber.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.