Position measurement system and lithographic apparatus
A position measurement system to measure a position of an object relative to a reference, the position measurement system including two interferometers, wherein each interferometer is configured to form a reference beam and a measurement beam from input radiation and to combine the reference beam an...
Gespeichert in:
Hauptverfasser: | , , |
---|---|
Format: | Patent |
Sprache: | eng |
Schlagworte: | |
Online-Zugang: | Volltext bestellen |
Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
Zusammenfassung: | A position measurement system to measure a position of an object relative to a reference, the position measurement system including two interferometers, wherein each interferometer is configured to form a reference beam and a measurement beam from input radiation and to combine the reference beam and the measurement beam to provide output radiation to be delivered to a detector, wherein each interferometer is configured such that the reference beam is formed by reflection of input radiation from a reflective element, and such that the measurement beam is formed by diffraction of input radiation from a grating on the object, and wherein the reference beam and the measurement beam are parallel to each other. |
---|