Attenuated embedded phase shift photomask blanks
US6653027B2 · kind B2 · utility
5Cited by
6References
41Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 26, 2001 |
| Grant date | Nov 25, 2003 |
| Priority date | — |
| Expiry date | Jul 28, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/265
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
An attenuating embedded phase shift photomask blank that produces a phase shift of the transmitted light is formed with an optically translucent film made of metal, silicon, nitrogen or metal, silicon, nitrogen and oxygen. A wide range of optical transmission (0.001% up to 20% at 193 nm) is obtained by this process. A post deposition process is implemented to obtain the desired properties (stability of optical properties with respect to laser irradiation and acid treatment) for use in industry. A special fabrication process for the sputter target is implemented to lower the defects of the film.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.