Projection exposure apparatus and device manufacturing method
US6266192A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 27, 1998 |
| Grant date | Jul 24, 2001 |
| Priority date | — |
| Expiry date | Feb 27, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70241
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A projection exposure apparatus includes an illumination optical system for illuminating a mask with light from a light source and a projection optical system having at least one diffractive optical element, for projecting an image of a pattern of the mask, as illuminated, onto a substrate. The at least one diffractive optical element is adapted to produce first diffraction light of an order to be used for projection of the image and second diffraction light of an order different from that of the first diffraction light. A portion of the second diffraction light is projected onto the substrate to provide a substantially uniform intensity distribution.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.