Process and apparatus for producing high-purity chemicals for the microelectronics industry
US6183720A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 8, 1998 |
| Grant date | Feb 6, 2001 |
| Priority date | — |
| Expiry date | Apr 8, 2018 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2006/80
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A process for producing a high-purity liquid chemical is provided. A chemical gas is successively purified over first and second purification columns by passing, countercurrently, a scrubbing solution of initially deionized high-purity water through the first and second purification columns, or by passing, countercurrently, a first scrubbing solution of initially deionized high-purity water through the first column and a second scrubbing solution of initially deionized water through the second column. Each of the scrubbing solutions gradually becomes a spent scrubbing solution loaded with impurity. A high-purity chemical gas leaves the second purification column with a low content of metallic elements. The high-purity chemical gas is subsequently dissolved in a liquid in a dissolution column including a top and a bottom. The liquid at the bottom of the dissolution column is collected and continuously recirculated, and is enriched with purified chemical gas, thereby forming a high-purity liquid chemical. The high-purity liquid chemical is subsequently distributed when a desired concentration of dissolved gas has been reached.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.