摘要:
A lithographic apparatus includes a stage to hold an object, the stage being moveable relative to a reference structure in a motion range; a magnet structure to provide a spatially varying magnetic field in at least a part of the motion range, the magnet structure being moveable relative to the reference structure and the stage; a first position measurement system to provide a first measurement signal corresponding to a position of the stage and/or the object in a measurement direction relative to the reference structure; a second position measurement system to provide a second measurement signal corresponding to a position of the stage relative to the magnet structure; and a data processor to correct the first measurement signal with a value dependent on the second measurement signal to provide a corrected first measurement signal representative of the position of the stage and/or the object relative to the reference structure in the measurement direction.
摘要:
A lithographic apparatus includes a stage to hold an object, the stage being moveable relative to a reference structure in a motion range; a magnet structure to provide a spatially varying magnetic field in at least a part of the motion range, the magnet structure being moveable relative to the reference structure and the stage; a first position measurement system to provide a first measurement signal corresponding to a position of the stage and/or the object in a measurement direction relative to the reference structure; a second position measurement system to provide a second measurement signal corresponding to a position of the stage relative to the magnet structure; and a data processor to correct the first measurement signal with a value dependent on the second measurement signal to provide a corrected first measurement signal representative of the position of the stage and/or the object relative to the reference structure in the measurement direction.
摘要:
A displacement measurement system, in particular for measuring the displacement of a substrate table in a lithographic apparatus relative to a reference frame is presented. The displacement measure system includes a plurality of displacement sensors mounted to the substrate table and a target associated with each displacement sensor mounted to the reference frame.
摘要:
A lithographic apparatus comprises an illumination system, an array of individually controllable elements, a substrate table, a projection system, a position encoder, an imaging device, and an image processing unit. The illumination system conditions a radiation beam. The array of individually controllable elements modulates the cross-section of the radiation beam. The substrate table supports a substrate. The projection system projects the modulated radiation beam onto a target portion of the substrate, thereby applying a pattern to the target portion of the substrate. The pattern comprises a first line and a second line. The first line is offset from the second line. The position encoder determines a position of the substrate table. The position encoder comprises a position sensor and a scale. The scale comprises a plurality of lines intended to be straight and parallel to one another. The imaging device obtains an image of the first line and the second line. The image processing unit measures the separation between the first line and the second line in a plurality of locations, and determines the non-uniformity of at least a part of the scale from the plurality of separations.
摘要:
A measurement system configured to measure a position dependent signal of an object table, the measurement system including at least one sensor mountable on the object table and a sensor target object mountable on a substantially stationary frame, and a mounting device configured to mount the sensor target object on the substantially stationary frame, wherein the measurement system further includes a compensator configured to compensate movements and/or deformations of the sensor target object with respect to the substantially stationary frame. The compensator may include a passive or an active damper and/or a feedback position controller. In an alternative embodiment, the compensator includes a gripping device which fixes the position of the sensor target object during a high accuracy movement of the movable object.
摘要:
An encoder-type measurement system is configured to measure a position dependent signal of a movable object. The measurement system includes a light source and a sensor. The light source and the sensor are mounted on one of the movable object or a substantially stationary frame. The measurement system also includes a reference object that includes a grating or grid mounted on the other of the movable object or the substantially stationary frame. The light source is configured to emit a light beam towards the reference object. The sensor is configured to detect light of the light source reflected by the reference object. The measurement system also includes an error detector capable of detecting errors in or on the grating or grid of the sensor target object during a continuous production process.
摘要:
A lithographic apparatus includes a position controller configured to control a position of a patterning device in its planar direction by selectively pressing at least one of the side faces of the patterning device. The position controller includes a gas pressure supply and one or more outflow openings directed towards at least one side face of the patterning device so as to exert pressurized gas on this side face in order to control the position of the patterning device in its planar direction in a contactless manner.
摘要:
A lithographic apparatus is provided with an optical encoder measurement system having an irradiation system to direct an irradiation beam to a first scale. The system has optics to direct a primary diffracted beam diffracted from the first scale upon irradiation by the irradiation beam to a second scale and a detector to detect a secondary diffracted beam after interference and a second diffraction of the primary diffracted irradiation beam on the second scale to measure the position of the first scale with respect to the second scale.
摘要:
A position measurement system configured to measure a position quantity of a movable object in a measurement direction, the system including a radiation source, a beam splitter to split the radiation beam in a measurement beam and a reference beam, a first reflective surface mounted on the movable object to receive the measurement beam, a second reflective surface mounted on a reference object to receive the reference beam, and a detector arranged to receive a first and second reflected beam reflected by the first and second reflective surface, respectively, and configured to provide a signal representative of the position quantity of the movable object based on the first and the second beam, wherein the radiation source and detector are mounted on an object that is different from the movable object and the reference object.
摘要:
A lithographic apparatus includes a position controller configured to control a position of a patterning device in its planar direction by selectively pressing at least one of the side faces of the patterning device. The position controller includes a gas pressure supply and one or more outflow openings directed towards at least one side face of the patterning device so as to exert pressurized gas on this side face in order to control the position of the patterning device in its planar direction in a contactless manner.