Projection optical system and projection exposure apparatus with the same, and device manufacturing method
US6459534B1 · kind B1 · utility
7Cited by
10References
10Claims
0Family size
Assignee
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Key dates
| Filing date | Jun 12, 2000 |
| Grant date | Oct 1, 2002 |
| Priority date | — |
| Expiry date | Jun 12, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B13/18
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A projection optical system for projecting a pattern of a mask onto a wafer, includes at least one aspherical surface lens having an aspherical surface on one side and a flat surface on the other side, the spherical surface satisfying a relation |&Dgr;ASPH/L|>1×10−6 where &Dgr;ASPH is the aspherical amount of the aspherical surface and L is an object-to-image distance of the projection optical system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.