Methods and systems for inspecting reticles using aerial imaging and die-to-database detection
US7123356B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 6, 2003 |
| Grant date | Oct 17, 2006 |
| Priority date | — |
| Expiry date | Oct 13, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/95676
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Methods and systems for inspecting a reticle are provided. In an embodiment, a method may include forming an aerial image of the reticle using a set of exposure conditions. The reticle may include optical proximity correction (OPC) features. The method may also include detecting defects on the reticle by comparing the aerial image to a reference image stored in a database. The reference image may be substantially optically equivalent to an image of the reticle that would be printed on a specimen by an exposure system under the set of exposure conditions. The reference image may not include images of the OPC features. Therefore, a substantial portion of the defects include defects that would be printed onto the specimen by the exposure system using the reticle under the set of exposure conditions. The method may also include indicating the defects that are detected in critical regions of the reticle.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.