Apparatus and method for measuring phase of extreme ultraviolet (EUV) mask and method of fabricating EUV mask including the method
US11635371B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 29, 2020 |
| Grant date | Apr 25, 2023 |
| Priority date | — |
| Expiry date | Oct 8, 2041 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2201/0636
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus and a method for correctly measuring a phase of an extreme ultraviolet (EUV) mask and a method of fabricating an EUV mask including the method are described. The apparatus for measuring the phase of the EUV mask includes an EUV light source configured to generate and output EUV light, at least one mirror configured to reflect the EUV light as reflected EUV light incident on an EUV mask to be measured, a mask stage on which the EUV mask is arranged, a detector configured to receive the EUV light reflected from the EUV mask, to obtain a two-dimensional (2D) image, and to measure reflectivity and diffraction efficiency of the EUV mask, and a processor configured to determine a phase of the EUV mask by using the reflectivity and diffraction efficiency of the EUV mask.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.