摘要:
A method for detecting radiation. The radiation detector includes a plurality of Faraday cups. Each Faraday cup being provided with a cover. Each cover comprising a window arrangement through which the radiation may pass into the Faraday cup. The window arrangement of each cover being different for each Faraday cup. Each Faraday cup housing a target configured to emit photoelectrons if the radiation is incident upon the target.
摘要:
An aberration detector for a lithographic apparatus is used. An imaging device captures an image of at least one pinhole feature of a target projected onto the imaging device by the projection system of the lithographic apparatus at two different locations separated in a direction parallel to the optical axis of the projection system. A controller obtains a representation of the aberration of the projection system from the captured images.