Halftone phase shift photomask and blanks for halftone phase shift photomask for producing it
US6764792B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 27, 2001 |
| Grant date | Jul 20, 2004 |
| Priority date | — |
| Expiry date | Apr 27, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/58
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The invention relates to a halftone phase shift photomask which is controlled with precision in terms of its transmittance at a wavelength applied to inspection, and measuring equipment, so that its quality can easily be assured even when its phase difference at an exposure wavelength is controlled at 180° C. with precision and its transmittance is set at 1 to 20% as desired at that wavelength. The halftone phase shift photomask (107) comprises on a transparent substrate (101) and a halftone phase shift film containing at least tantalum, oxygen, carbon and nitrogen, and has a multilayer structure comprising at least two or more different layers (102) and (103).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.