Exposure method and apparatus
US7095481B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 12, 2003 |
| Grant date | Aug 22, 2006 |
| Priority date | — |
| Expiry date | Jul 25, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70133
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An exposure method for projecting, through a projection optical system, a predetermined pattern formed on a mask onto an object to be exposed. The exposure method includes the steps of dividing an effective light source area for illuminating the mask into plural point light sources, calculating a Zernike sensitivity coefficient that represents a sensitivity of a change of image quality of the predetermined pattern to a change of a Zernike coefficient, when wave front aberration in the projection optical system is developed into a Zernike polynomial for all divided point light sources, determining an effective light source distribution based on a combination of Zernike sensitivity coefficient of all divided point light sources, and forming the effective light source distribution by intensity of each point light source.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.