Large-area, scan-and-repeat, projection patterning system with unitary stage and magnification control capability
US5710619A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 31, 1995 |
| Grant date | Jan 20, 1998 |
| Priority date | — |
| Expiry date | Oct 31, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70791
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In numerous applications of large-area patterning systems, the preferred image magnification is unity. However, in some applications, the size of the substrate may change slightly due to various thermal and/or chemical processing steps. To compensate for scale changes of the substrate, the magnification of the imaging system must vary slightly from unit magnification (typically by a fraction of a percentage) so that a layer already patterned on the substrate will have, after processing, proper image registration with the subsequent layer. This disclosure describes a lithography system for exposing large substrates at high imaging resolution and high exposure throughput, and specifically relates to a scan-and-repeat patterning system that employs a unitary mask-substrate stage and enables projection imaging of a substrate with capability to control the image magnification to compensate for changes of substrate dimensions occurring as a result of previous process steps. A combination of optical and mechanical compensation is used to provide the necessary magnification control, including anamorphic magnification variation in which the fine adjustment is of different magnitudes in x an…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.