Mask blank, phase-shift mask, and method of manufacturing semiconductor device
US11442357B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 8, 2019 |
| Grant date | Sep 13, 2022 |
| Priority date | — |
| Expiry date | May 8, 2039 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/0337
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Provided is a mask blank, including a phase shift film. The phase shift film has a structure where a first layer and a second layer are stacked in this order from a side of the transparent substrate. The first layer is provided in contact with a surface of the transparent substrate. Refractive indexes n1 and n2 of the first layer and the second layer, respectively, at a wavelength of an exposure light of an ArF excimer laser satisfy the relation n1<n2. Extinction coefficients k1 and k2 of the first layer and the second layer, respectively, at a wavelength of the exposure light satisfy the relation k1<k2. Film thicknesses d1 and d2 of the first layer and the second layer, respectively, satisfy the relation d1<d2.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.