Surface inspection system and method using summed light analysis of an inspection surface
US7046352B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 19, 2002 |
| Grant date | May 16, 2006 |
| Priority date | — |
| Expiry date | Jan 23, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/30148
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The present invention discloses methods of conducting surface inspections using summed light. One method includes the steps of measuring summed light intensity values for the substrate, generating comparison values for the substrate, and then comparing the measured summed light intensity values with the comparison values to determine whether there are defects in the substrate. In another embodiment, a method includes the steps of generating a reference cluster using measured summed light intensity values for selected portions of the inspection surface. Other summed light intensity values are measured and then compared with the reference cluster. Using this comparison, a determination is made as to whether a defect is present. Another embodiment uses a constant baseline signal which is compared to actual light intensity values to determine whether a substrate defect is present. In yet another embodiment a substrate is inspected for the presence of defects by conducting a pixel-by-pixel summed light inspection of the substrate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.