Mask
US9891518B2 · kind B2 · utility
1Cited by
3References
3Claims
0Family size
Assignees
Inventors
Key dates
| Filing date | Nov 19, 2014 |
| Grant date | Feb 13, 2018 |
| Priority date | — |
| Expiry date | Dec 26, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/00
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A mask, comprising an opaque region, a first semi-transparent region, and a second semi-transparent region. The transmittance of the second semi-transparent region is less than that of the first semi-transparent region. The mask solves the over-etching problem caused by the difference between the thicknesses of photoresist in different regions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.