Catadioptric imaging system for high numerical aperture imaging with deep ultraviolet light
US7564633B2 · kind B2 · utility
5Cited by
9References
20Claims
0Family size
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Key dates
| Filing date | Feb 18, 2005 |
| Grant date | Jul 21, 2009 |
| Priority date | — |
| Expiry date | Sep 12, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70225
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A catadioptric imaging system for micro-lithographic projection features a high numerical aperture objective where most of the focusing power is produced by reflection and refraction angles are limited to avoid additional aberration. A field correcting optic is appended to a Mangin mirror in an immersive configuration for raising the numerical aperture. The optical connection between the Mangin mirror and the field correcting optic is arranged to control refraction angles by limiting angles of incidence or refractive index differences. A radially symmetric polarizing effect is achieved in a pupil to improve image contrast.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.