Method and apparatus for inspecting pattern defects
US7388979B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 22, 2004 |
| Grant date | Jun 17, 2008 |
| Priority date | — |
| Expiry date | Aug 2, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06T2207/30148
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The present invention relates to a pattern defect inspection method and apparatus that reveal ultramicroscopic defects on an inspection target in which ultramicroscopic circuit patterns are formed, and inspect the defects with high sensitivity and at a high speed. The present invention provides a pattern inspection apparatus for comparing the images of corresponding areas of two formed patterns that should be identical with each other, and judging any mismatched image area as a defect. The pattern inspection apparatus includes means for performing an image comparison process on a plurality of areas in a parallel manner. Further, the pattern inspection apparatus also includes means for converting the gradation of the image signals of compared images in each of a plurality of different processes. Therefore, the present invention can properly detect defects even if the same patterns of compared images differ in brightness.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.