Phase-shifting mask for equal line/space dense line patterns
US7504184B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 27, 2005 |
| Grant date | Mar 17, 2009 |
| Priority date | — |
| Expiry date | May 31, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/28
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A phase-shifting mask suited for equal line/space, small pitched, dense line pattern is disclosed. The phase-shifting mask includes a transparent substrate, a partially shielded mesa line pattern of first phase formed on the substrate, and a 100% clear recessed line pattern of second phase etched into the substrate and is disposed right next to the partially shielded mesa line pattern. The partially shielded mesa line pattern has a plurality of alternating 45-degree, oblique areas and 100% transmittance clear regions of the first phase. The partially shielded mesa line pattern and the clear recessed line pattern have the same line width. The light that passes through the clear regions of the first phase and the light that passes through the clear recessed line pattern of second phase have a phase difference of 180 degree.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.