Apparatus for enhancing depth of focus using birefringent material
US6057970A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 24, 1998 |
| Grant date | May 2, 2000 |
| Priority date | — |
| Expiry date | Sep 24, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70216
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present invention relates to an apparatus for forming fine patterns in semiconductor devices, display devices and micro-electro-mechanical systems and more particularly to an image projecting system using an optical component, which is made of birefringent material, in the lithography techniques. The lithography apparatus according to the present invention comprises an optical lens system in which an image of a photomask is transferred to an object by a light source, wherein said optical lens system comprises a plurality of isotropic optical unit and at least one birefringent optical unit, said birefringent optical unit including at least one of said birefringent optical components.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.