Photomask blank and photomask making method
US7767367B2 · kind B2 · utility
9Cited by
9References
35Claims
0Family size
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Inventors
Key dates
| Filing date | Mar 8, 2007 |
| Grant date | Aug 3, 2010 |
| Priority date | — |
| Expiry date | Jul 15, 2028 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31616
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A photomask blank comprises a transparent substrate, a light-shielding film deposited on the substrate and comprising a metal or metal compound susceptible to fluorine dry etching, and an etching mask film deposited on the light-shielding film and comprising another metal or metal compound resistant to fluorine dry etching. When the light-shielding film is dry etched to form a pattern, pattern size variation arising from pattern density dependency is reduced, so that a photomask is produced at a high accuracy.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.