ASML Holding N.V.
Radiation source

Abstract:

A radiation source comprises: an emitter for emitting a fuel target towards a plasma formation region; a laser system for hitting the target with a laser beam to generating a plasma; a collector for collecting radiation emitted by the plasma; an imaging system configured to capture an image of the target; one or more markers at the collector and within a field of view of the imaging system; and a controller. The controller receives data representative of the image; and controls operation of the radiation source in dependence on the data.