Photomask, exposure apparatus, and method of fabricating three-dimensional semiconductor memory device using the same
US11662659B2 · kind B2 · utility
0Cited by
4References
20Claims
0Family size
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Key dates
| Filing date | May 3, 2021 |
| Grant date | May 30, 2023 |
| Priority date | — |
| Expiry date | Jul 29, 2041 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10B43/50
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Disclosed are a photomask, an exposure apparatus, and a method of fabricating a three-dimensional semiconductor memory device using the same. The photomask may include a mask substrate, a first mask pattern on the mask substrate, and an optical path modulation substrate. The optical path modulation substrate may include a first region on a portion of the first mask pattern, and a second region on another portion of the first mask pattern. The second region has a thickness that is less than a thickness of the first region.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.