Photomask blank, photomask and fabrication method thereof
US7625676B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Oct 21, 2005 |
| Grant date | Dec 1, 2009 |
| Priority date | — |
| Expiry date | Jul 28, 2027 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31616
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A light-shieldable film is formed on one principal plane of an optically transparent substrate, and the light-shieldable film has a first light-shieldable film and a second light-shieldable film overlying the first light-shieldable film. The first light-shieldable film is a film that is not substantially etched by fluorine-based (F-based) dry etching and is primarily composed of chromium oxide, chromium nitride, chromium oxynitride or the like. The second light-shieldable film is a film that is primarily composed of a silicon-containing compound that can be etched by F-based dry etching, such as silicon oxide, silicon nitride, silicon oxynitride, silicon/transition-metal oxide, silicon/transition-metal nitride or silicon/transition-metal oxynitride.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.