Structure and method for providing a gas purge for a vacuum particle sensor installed in a corrosive or coating environment
US5360980A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 26, 1993 |
| Grant date | Nov 1, 1994 |
| Priority date | — |
| Expiry date | Feb 26, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2015/0046
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A structure and an apparatus are provided for use in particle sensor installed to monitor particle level of a process chamber. The process chamber receives process gas from a supply line and removes gas through an exhaust line. The particle sensor's optical components are prevented from contamination by corrosive or coating species in the effluent from the process, by a gas purge line installed in the particle sensor. The gas purge line allows a flow of gas to purge the optical components at a flux not less than the flux of gas being removed from the process chamber in the exhaust line. The flux out of the particle sensor prevents the undesired species from reaching the optical components of the particle sensor from the sampling area where the particle sensor detects the particle level.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.