Scanner for step and scan lithography system
US5602619A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 27, 1994 |
| Grant date | Feb 11, 1997 |
| Priority date | — |
| Expiry date | Sep 27, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70691
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A mechanical scanner design suitable for use in a step and scan lithography system with arbitrary image magnification includes a projection optical system (20) and a relatively rotatable platform (40). The optical system has the property that a point within a predetermined object field in a first plane is imaged with suitable magnification at a corresponding point within a corresponding image field in a second plane, parallel to the first plane. The object and image fields are displaced from each other. A light source (22) illuminates an aperture such as a slit which is imaged in the object plane, whereupon a slit image is formed in the image plane. The reticle and wafer are mounted to the platform at respective locations in the object and image planes. The axis (42) of relative rotation is perpendicular to the conjugate planes, and located relative to the optical system such that the object field and image field slit images are at respective distances from the rotation axis that are in the ratio equal to the magnification.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.