Method for tuning an attenuating phase shift mask
US6027837A · kind A · utility
5Cited by
1References
28Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 4, 1999 |
| Grant date | Feb 22, 2000 |
| Priority date | — |
| Expiry date | Jan 4, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/84
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present invention provides a method and an apparatus for tuning the phase shifting of a phase shift mask having an attenuating phase shifting material providing at least 160.degree. of phase shift. The method comprising the utilization of a phase measurement and selective etching operations which reduces the challenge of making an exacting 180.degree. phase shifting mask. An attenuated phase shift mask structure is also disclosed in the present invention.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.