Method of reducing a wave front aberration, and computer program product
US7580113B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 23, 2006 |
| Grant date | Aug 25, 2009 |
| Priority date | — |
| Expiry date | Oct 25, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70891
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method of reducing a wave front aberration is provided for a lithographic process whereby the reducing is based on the selected pattern to be printed and the selected illumination mode used for exposure. Wave front aberrations of a projection system of a lithographic apparatus are measured and reduced by calculating adjustments of optical elements of the projection system and applying the calculated adjustments to the projection system. The calculation of adjustments is based on information on a spatial distribution of radiant intensity in a pupil of the projection system as present during exposing the radiation sensitive layer, and is limited to aberrations in projection lens pupil areas of relative high radiant flux.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.