Film measurement system with improved calibration
US5771094A · kind A · utility
115Cited by
3References
25Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 29, 1997 |
| Grant date | Jun 23, 1998 |
| Priority date | — |
| Expiry date | Jan 29, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J2003/2866
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The pixel position-to-wavelength calibration function of film measurement devices such as spectroscopic ellipsometers and spectroreflectometers may shift due to temperature and humidity changes and mechanical factors. One or more wavelength markers provided by the light source or reference sample may be used to correct the calibration function. The pixel positions of one or more persistent wavelength markers are noted during the calibration process and the current positions of such markers are again noted to account for shifts due to various factors to correct the calibration function.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.