Alternating phase shift mask
US11635679B1 · kind B1 · utility
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6References
20Claims
0Family size
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Key dates
| Filing date | Sep 25, 2020 |
| Grant date | Apr 25, 2023 |
| Priority date | — |
| Expiry date | Jul 10, 2041 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/30
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An alternating phase-shifting mask (Alt-PSM) comprising a 0° phase portion having a first width and a 180° phase portion having a second width greater than the first width. Example differences between the width of the 180° phase portion and the 0° phase portion may be 10 nm, 15 nm, or 20 nm. An Alt-PSM having phase portions of different widths can have an aerial image intensity transmission graph that is symmetric, for example, at 0.2-0.3 intensity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.