Wafer inspection using difference images
US11270430B2 · kind B2 · utility
3Cited by
2References
18Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 4, 2018 |
| Grant date | Mar 8, 2022 |
| Priority date | — |
| Expiry date | Dec 26, 2040 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/30148
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Systems and methods increase the signal to noise ratio of optical inspection of wafers to obtain higher inspection sensitivity. The computed reference image can minimize a norm of the difference of the test image and the computed reference image. A difference image between the test image and a computed reference image is determined. The computed reference image includes a linear combination of a second set of images.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.