Curved reticle by mechanical and phase bending along orthogonal axes
US12346029B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 4, 2022 |
| Grant date | Jul 1, 2025 |
| Priority date | — |
| Expiry date | Apr 10, 2043 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B5/0891
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Collection reflectors with multiple reflector elements defined on a curved surface are used to collect EUV optical radiation from an EUV emitting area. Each of the reflector elements can image the emitting area at or near a corresponding reflective element of a second multi-element reflector that overlaps radiation from each of the multiple reflector element of the collection reflector to illuminate a grating reticle. Systems with such a collection reflector can use fewer optical elements. In addition, grating reticles are defined on a curve substrate an include a plurality of grating phase steps so that the grating reticle provides phase curvature along two axes but with physical curvature along a single axis. Methods of producing varying duty cycle 1D patterns are also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.