Lithographic apparatus, lens interferometer and device manufacturing method
AssigneeASML Netherlands B.V.
InventorMarcus Adrianus Van De Kerkhof
Life of this patent
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Abstract
A lithographic apparatus includes an illumination system that is configured to condition a radiation beam; a projection system that is configured to project at least a portion of the radiation beam as a projected radiation beam; and a lens interferometer for sensing a wavefront state of the projected radiation beam. The lens interferometer is provided with a polarizing element so as to be capable of sensing a polarisation state of the projected radiation beam.
Claims30
A lithographic apparatus, comprising:
- an illumination system configured to condition a radiation beam;
- a projection system configured to project a portion of the radiation beam as a projected radiation beam;
- a substrate table, constructed to hold a substrate to receive the projected radiation beam;
- a lens interferometer for sensing a wavefront state of the projected radiation beam, wherein the lens interferometer is provided with a polarizing element so as to be capable of sensing a polarisation state of the projected radiation beam, wherein the lens interferometer comprises a lens interferometer marker arranged in a surface of the substrate table, and a detector, the lens interferometer marker comprising the polarizing element, the detector being arranged for receiving the portion of the received projected beam as transmitted by the polarizing element.
A lens interferometer for a lithographic apparatus, the lithographic apparatus comprising an illumination system configured to condition a radiation beam, a projection system configured to project a portion of the radiation beam as a projected radiation beam, and a substrate table, constructed to hold a substrate to receive the projected radiation beam;
- the lens interferometer being arranged for sensing a wavefront state of a radiation beam, wherein the lens interferometer is provided with a polarizing element so as to be capable of sensing a polarization state of the radiation beam at the substrate table, wherein the lens interferometer comprises a lens interferometer marker and a detector, the lens interferometer marker comprising the polarizing element, the detector being arranged for receiving the at least portion of the received projected beam as transmitted by the polarizing element.
A device manufacturing method, comprising:
- selecting an illumination mode for imaging a pattern onto a substrate held on a substrate table;
- projecting at least a portion of a radiation beam as a projected radiation beam in accordance with the selected illumination mode;
- providing a lens interferometer for sensing a wavefront state of the projected radiation beam;
- providing the lens interferometer with a polarizing element so as to be capable of sensing a polarisation state of the projected radiation beam;
- adjusting a polarization distribution of the selected illumination mode on the basis of the sensed polarization state;
- and
- imaging the pattern onto a radiation sensitive substrate using the adjusted polarization distribution and the selected illumination mode.
Dependencies are inferred from the claim text.