Method of repetitively imaging a mask pattern on a substrate, and apparatus for performing the method
US5674650A · kind A · utility
90Cited by
6References
26Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 1, 1995 |
| Grant date | Oct 7, 1997 |
| Priority date | — |
| Expiry date | Aug 1, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F9/7026
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method and apparatus for repetitively imaging a mask pattern (C) on a substrate (W) are described. The focusing of the projection lens system used for imaging and various other parameters of the apparatus and the projection lens system (PL), as well as illumination doses can be measured accurately and reliably, and measuring devices of the apparatus can be calibrated, by measuring an image of a new asymmetrical test mark formed in the photoresist on the substrate (W) by means of a projection beam (PB).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.