Multi mirror system for an illumination system
US7583433B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 19, 2004 |
| Grant date | Sep 1, 2009 |
| Priority date | — |
| Expiry date | Aug 19, 2024 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S359/90
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
There is provided a multi-mirror-system for an illumination system, especially for lithography with wavelengths ≦193 nm. The system includes light rays traveling along a light oath from an object plane to an image plane, and an arc-shaped field in the image plane, whereby a radial direction in the middle of the arc-shaped field defines a scanning direction. The first mirror and the second mirror are arranged in the light path in such a position and having such a shape, that the edge sharpness of the arc-shaped field in the image plane is smaller than 5 mm in the scanning direction. Furthermore, the light rays are impinging on the first mirror and the second mirror with incidence angles ≦30° or ≧60° relative to a surface normal of the first and second mirror.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.