Photomask blank, photomask and method for producing those
US7618753B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Aug 10, 2005 |
| Grant date | Nov 17, 2009 |
| Priority date | — |
| Expiry date | Nov 13, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/32
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A metal film is provided as a light shielding layer on one principle surface of a photomask substrate. The metal film cannot be substantially etched by chlorine-based dry etching containing oxygen ((Cl+O)-based dry etching) and can be etched by chlorine-based dry etching not containing oxygen (Cl-based dry etching) and fluorine-based dry etching (F-based dry etching). On the light shielding layer, a metal compound film as an antireflective layer. The metal compound film cannot be substantially etched by chlorine-based dry etching not containing oxygen (Cl based) and can be etched by at least one of chlorine-based dry etching containing oxygen ((Cl+O) based) and fluorine-based dry etching (F based).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.