Position sensor
The invention provides a position sensor (300) which comprises an optical system (305,306) configured to provide measurement radiation (304) to a substrate (307). The optical system is arranged to receive at least a portion of radiation (309) diffracted by a mark (308) provided on the substrate. A p...
Saved in:
Main Authors | , , , , , |
---|---|
Format | Patent |
Language | English |
Published |
17.05.2022
|
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | The invention provides a position sensor (300) which comprises an optical system (305,306) configured to provide measurement radiation (304) to a substrate (307). The optical system is arranged to receive at least a portion of radiation (309) diffracted by a mark (308) provided on the substrate. A processor (313) is applied to derive at least one position-sensitive signal (312) from the received radiation. The measurement radiation comprises at least a first and a second selected radiation wavelength. The selection of the at least first and second radiation wavelengths is based on a position error swing-curve model. |
---|---|
Bibliography: | Application Number: US201917254601 |