Method for measuring optical feature of exposure apparatus and exposure apparatus having means for measuring optical feature
US6825932B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 7, 2002 |
| Grant date | Nov 30, 2004 |
| Priority date | — |
| Expiry date | Aug 7, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70616
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An exposure apparatus and a method of operating the exposure apparatus. The exposure apparatus includes a light source generating illumination light and a projection optical system. A detector detects illumination light reaching a plurality of measuring positions within an image field of the projection optical system. An illumination area setting and changing device arranged between the light source and the detector sets an illumination area on a mask to illuminate a pattern on the mask, and changes the illumination area during detection of a projected image of the pattern by the detector while illumination light is maintained on the mask. The illumination area setting and changing device changes the illumination area from a first illumination area illuminating a first pattern on the mask to a second illumination area illuminating both the first pattern and a second pattern which differs from the first pattern.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.