Azimuthal scanning of a structure formed on a semiconductor wafer
US7414733B2 · kind B2 · utility
4Cited by
24References
18Claims
0Family size
Assignee
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Key dates
| Filing date | May 25, 2007 |
| Grant date | Aug 19, 2008 |
| Priority date | — |
| Expiry date | May 25, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/956
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A structure formed on a semiconductor wafer is examined by obtaining measurements of cross polarization components of diffraction beams, which were obtained from scanning an incident beam over a range of azimuth angles to obtain an azimuthal scan. A zero azimuth position is determined based on the azimuthal scan. The cross polarization components are zero at the zero azimuth position. A measured diffraction signal is obtained using an azimuth angle to be used in optical metrology of the structure. Misalignment of the azimuth angle is detected using the measured diffraction signal and the determined zero azimuth position.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.