Method for calculating non-correctable EUV blank flatness for blank dispositioning
US10552569B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 11, 2018 |
| Grant date | Feb 4, 2020 |
| Priority date | — |
| Expiry date | May 10, 2038 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/84
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present disclosure generally relates to semiconductor structures and, more particularly, to mask structures and methods of manufacture. The method includes determining a plane through a frontside surface and a backside surface of a mask, each plane representing a flatness of the frontside surface and the backside surface, respectively; subtracting, using at least one computing device, a difference between the plane of the frontside surface and the plane of the backside surface to find a thickness variation; generating, using the at least one computing device, a fitting to fit the thickness variation; and subtracting, using the at least one computing device, the fitting from the thickness variation to generate a residual structure for collecting a residual flatness measurement.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.