Multiple wavelength polarization-modulated ellipsometer with phase-generated carrier
US5548404A · kind A · utility
31Cited by
15References
55Claims
0Family size
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Key dates
| Filing date | Sep 23, 1994 |
| Grant date | Aug 20, 1996 |
| Priority date | — |
| Expiry date | Sep 23, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/211
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus for analyzing a sample wherein at least two orthogonally polarized, intensity and phase modulated laser beams with different wavelengths and frequencies of intensity and phase modulation are directed onto the sample, and the signals derived from the laser beams which interact with the sample are synchronously demodulated to determine characteristics of the sample such as index of refraction, absorption coefficient and film thickness. A reference beam can be provided to correct for noise and drift.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.