Interferometer, lithography apparatus, and method of manufacturing article
US9625836B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 10, 2014 |
| Grant date | Apr 18, 2017 |
| Priority date | — |
| Expiry date | Jun 12, 2035 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F9/7049
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An interferometer includes: an optical system configured to generate interfering light by dividing light from a light source, and combining reference light and measurement light; a detector configured to detect the interfering light generated by the optical system; and an optical member configured to give spatial coherence to the light from the light source before the detector detects the light from the light source. The optical member gives higher spatial coherence in a second direction serving as a direction of a line of intersection of a cross section of a beam of the light incident on the optical member, and a plane including optical paths of the light from the light source before being divided by the optical system, the reference light, the measurement light, and the interfering light, than in a first direction perpendicular to the plane.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.