Measurement system, calibration method, lithographic apparatus and positioner

A calibration method comprising:

• positioning a sensor plate in different positions relative to a projection system, such that a first free end of an optical fiber bundle is arranged to receive light from the sensor plate,
• wherein a second free end of the optical fiber bundle opposite the first free end of the optical fiber bundle is arranged such that light emanating from fibers of the optical fiber bundle at the second free end illuminates a detector,
• wherein each fiber illuminates a different detector area of the detector,
• wherein a control unit is configured to match each detector area with a corresponding location in a pupil plane of the projection system by collecting measurement data corresponding to different positions of the sensor plate relative to the projection system, and
• wherein the sensor plate is arranged on a short-stroke module configured for fine positioning of a substrate table relative to a reference, the detector is arranged on a long-stroke module configured for coarse positioning of the substrate table relative to the reference, and the optical fiber bundle is arranged on the long-stroke module;
• collecting measurement data corresponding to the different positions;
• and
• matching each detector area of the detector with a corresponding location in a pupil plane of the projection system using the collected measurement data.

A lithographic apparatus comprising:

• an illumination system configured to condition a radiation beam;
• a support constructed to support a patterning device, the patterning device being capable of imparting the radiation beam with a pattern in its cross-section to form a patterned radiation beam;
• a substrate table constructed to hold a substrate with multiple target portions arranged in one or more columns parallel to an axis;
• a projection system configured to project the patterned radiation beam onto a target portion of the substrate;
• and
• a measurement system comprising:
• a sensor plate arranged on a short-stroke module configured for fine positioning of the substrate table relative to a reference;
• a detector comprising an array of detector areas, wherein the detector is arranged on a long-stroke module configured for coarse positioning of the substrate table relative to the reference;
• a randomly ordered optical fiber bundle arranged on the long-stroke module;
• a positioner configured to position the sensor plate in the patterned radiation beam projected by the projection system;
• and
• a control unit configured to control the positioning of the sensor plate and to obtain measurement data from an output of the detector,
• wherein a first free end of the optical fiber bundle is arranged to receive light from the sensor plate,
• wherein a second free end of the optical fiber bundle opposite the first free end of the optical fiber bundle is arranged such that light emanating from fibers of the optical fiber bundle at the second free end illuminates the detector, wherein each fiber illuminates a different detector area of the detector, and
• wherein the control unit is configured to match each detector area with a corresponding location in a pupil plane of the projection system by collecting measurement data corresponding to different positions of the sensor plate relative to the projection system.

A positioner for a substrate table of a lithographic apparatus, comprising:

• a long-stroke module configured for coarse positioning of the substrate table relative to a reference;
• a short-stroke module supported by the long-stroke module configured for fine positioning of the substrate table relative to the reference;
• a sensor plate arranged on the short-stroke module;
• a detector arranged on the long-stroke module;
• an optical fiber bundle arranged on the long-stroke module, wherein a cross-section of a fiber in the optical fiber bundle has an outer diameter;
• and
• a control unit configured to control the long-stroke module and the short-stroke module to position the substrate table relative to the reference,
• wherein a first free end of the optical fiber bundle is arranged to receive light from the sensor plate,
• wherein a second free end of the optical fiber bundle opposite the first free end of the optical fiber bundle is arranged such that light emanating from the fibers of the optical fiber bundle at the second free end illuminates the detector, and
• wherein the control unit is configured to keep a moving range of the short-stroke module relative to the long-stroke module within at most half the outer diameter of the cross-section of the optical fibers during at least a predetermined measurement period.

A lithographic apparatus comprising:

• an illumination system configured to condition a radiation beam;
• a support constructed to support a patterning device, the patterning device being capable of imparting the radiation beam with a pattern in its cross-section to form a patterned radiation beam;
• a substrate table constructed to hold a substrate with multiple target portions arranged in one or more columns parallel to an axis;
• a projection system configured to project the patterned radiation beam onto a target portion of the substrate;
• and
• a positioner configured to position the substrate table, the positioner comprising:
• a long-stroke module configured for coarse positioning of the substrate table relative to a reference;
• a short-stroke module supported by the long-stroke module configured for fine positioning of the substrate table relative to the reference;
• a sensor plate arranged on the short-stroke module;
• a detector arranged on the long-stroke module;
• an optical fiber bundle arranged on the long-stroke module, wherein a cross-section of a fiber in the optical fiber bundle has an outer diameter;
• and
• a control unit configured to control the long-stroke module and the short-stroke module to position the substrate table relative to the reference,
• wherein a first free end of the optical fiber bundle is arranged to receive light from the sensor plate,
• wherein a second free end of the optical fiber bundle opposite the first free end of the optical fiber bundle is arranged such that light emanating from the fibers of the optical fiber bundle at the second free end illuminates the detector, and
• wherein the control unit is configured to keep a moving range of the short-stroke module relative to the long-stroke module within at most half the outer diameter of the cross-section of the optical fibers during at least a predetermined measurement period.