Optical system for measuring samples using short wavelength radiation
US7369233B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 19, 2003 |
| Grant date | May 6, 2008 |
| Priority date | — |
| Expiry date | May 26, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/8806
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In an optical system measuring sample characteristics, by reducing the amount of ambient absorbing gas or gases and moisture present in at least a portion of the illumination and detection paths experienced by vacuum ultraviolet (VUV) radiation used in the measurement process, the attenuation of such wavelength components can be reduced. Such reduction can be accomplished by a process without requiring the evacuation of all gases and moisture from the measurement system. In one embodiment, the reduction can be accomplished by displacing at least some of the absorbing gas(es) and moisture present in at least a portion of the measuring paths so as to reduce the attenuation of VUV radiation. In this manner, the sample does not need to be placed in a vacuum, thereby enhancing system throughput.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.