System and method for determining and controlling contamination
US6759254B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 24, 2002 |
| Grant date | Jul 6, 2004 |
| Priority date | — |
| Expiry date | Sep 24, 2022 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D53/22
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A preferred embodiment includes a method for monitoring the performance of a filter positioned in an airstream in a semiconductor processing system. The method includes sampling the airstream at a location upstream of the filter to detect the molecular contaminants present in the airstream; identifying a target species of the contaminants upstream; selecting a non-polluting species of a contaminant having a concentration greater than a concentration of the target species; measuring the non-polluting species in the airstream at a plurality of locations; and determining the performance of the filter with respect to the target species from measurements of the non-polluting species. The plurality of locations includes a location downstream of the filter and at a location within the filter. Further, the method for monitoring includes generating a numerical representation of a chromatogram of the airstream sampled at a location upstream of the filter. The method for monitoring includes the non-polluting species having a molecular weight that is lower than that of the target species. In addition, in the method for monitoring the step of sampling includes collecting refractory compounds, h…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.