Method and apparatus for inspecting or testing a sample by optical metrology
US6031602A · kind A · utility
4Cited by
5References
7Claims
0Family size
Assignee
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Key dates
| Filing date | Apr 29, 1998 |
| Grant date | Feb 29, 2000 |
| Priority date | — |
| Expiry date | Apr 29, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B9/02095
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A sample (1) is inspected or tested by illumination in which a line of coherent radiation (2) is scanned across the sample (1) with zero shear in the direction of scan. Two laterally displaced images of the sample (1) are generated which are phase stepped by stepping or ramping the phase of one of the two images during each of the line scans so that successive lines are incremented in phase to encode temporally information about the sample in one frame. The encoded information is decoded by running a vertical convolution mask (17) over the encoded frame image.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.