Photolithography method using coherence distance control
US5946079A · kind A · utility
8Cited by
9References
4Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Oct 31, 1997 |
| Grant date | Aug 31, 1999 |
| Priority date | — |
| Expiry date | Oct 31, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70616
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method for mapping coherence and a method and system for reducing varying coherence conditions of a stepper field exposure tool used in lithographic patterning. The present invention describes a method and system to reduce the effective light source of a stepper field exposure tool in order to decrease the variance of coherence conditions across a stepper field. The decrease in variance of coherence conditions across the stepper field corrects for a wide range of linewidth variation in lithographic patterning.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.