Mask blank glass substrate, multilayer reflective film coated substrate, mask blank, mask, and methods of manufacturing the same
US9195131B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 28, 2012 |
| Grant date | Nov 24, 2015 |
| Priority date | — |
| Expiry date | May 5, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/60
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Provided is a mask blank glass substrate that has high surface smoothness, that is formed with a fiducial mark capable of improving the detection accuracy of a defect position or the like, and that enables reuse or recycling of a glass substrate included therein. An underlayer is formed on a main surface, on the side where a transfer pattern is to be formed, of a glass substrate for a mask blank. The underlayer serves to reduce surface roughness of the main surface of the glass substrate or to reduce defects of the main surface of the glass substrate. A surface of the underlayer is a precision-polished surface. A fiducial mark which provides a reference for a defect position in defect information is formed on the underlayer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.