Abstract:
PROBLEM TO BE SOLVED: To provide a more accurate position measurement system using a calibration which takes less time than a conventional calibration method.SOLUTION: A position measurement system includes a first part EG, a second part ES and a computational unit. The first part and the second part determine a position of a first member relative to a second member by providing a position signal representing a position of the first part relative to the second part. The computational unit comprises an input terminal for receiving the position signal. The computational unit is configured to, in use, apply a conversion to the position signal to obtain a signal representing a position of the first member relative to the second member, and apply an adjustment to the conversion to at least partly compensate for a drift of the first part or the second part or both. The adjustment is based on a predetermined drift characteristic of the first part or the second part or both respectively. The predetermined drift characteristic includes one or more base shapes of the first part and/or the second part.
Abstract:
PROBLEM TO BE SOLVED: To provide an improved lithographic apparatus of which positional accuracy performance is advanced.SOLUTION: The lithographic apparatus includes: a support being moveable relative to a reference structure in a direction; a first position measurement system configured to provide a first measurement signal in a first frequency range, the first measurement signal representative of a position of the support relative to the reference structure in the direction; a second position measurement system configured to provide a second measurement signal in a second frequency range, the second measurement signal representative of the position of the support relative to the reference structure in the direction; and a processor configured to (a) filter the first measurement signal so as to attenuate a signal component having a frequency in the second frequency range, (b) filter the second measurement signal so as to attenuate a signal component having a frequency in the first frequency range, and (c) combine the filtered first measurement signal and the filtered second measurement signal into a combined measurement signal representative of the position of the support relative to the reference structure in the direction.
Abstract:
PROBLEM TO BE SOLVED: To provide a displacement measuring system of high accuracy in a lithography device.SOLUTION: A displacement measuring system comprises at least one retroreflector, and a diffraction grating. The displacement measuring system is configured to measure displacement by providing a first radiation beam to a measuring system, and the diffraction grating diffracts the first radiation beam first time to form plural diffracted beams. At least one retroreflector sequentially turns the diffracted beams in a direction to diffract the beams on the diffraction grating second time. At least one reflector turns the diffracted beams on the diffraction grating at least third time before the diffracted beams are re-coupled to form a second beam. Then, a displacement system is provided with a sensor configured to receive the second beam and determine displacement according to a strength of the second beam.
Abstract:
PROBLEM TO BE SOLVED: To provide a lithographic apparatus including a position measurement system for accurately measuring a substrate table position.SOLUTION: The lithographic apparatus comprises: a substrate table position measurement system for measuring a substrate table position; and a projection system position measurement system for measuring a projection system position. The substrate table position measurement system comprises: a substrate table reference element mounted on the substrate table; and a first sensor head. The substrate table reference element extends in a measurement plane substantially parallel to a holding plane of a substrate on the substrate table. The holding plane is arranged at one side of the measurement plane and the first sensor head is arranged at an opposite side of the measurement plane. The projection system position measurement system includes one or more projection system reference elements and a sensor assembly. The sensor head and the sensor assembly or the associated projection system measurement elements are mounted on a sensor frame.
Abstract:
PROBLEM TO BE SOLVED: To reduce or remove risk of errors in sensor measurements.SOLUTION: The lithographic apparatus has a first outlet to provide a thermally conditioned fluid with a first flow characteristic to at least part of a sensor beam path, and a second outlet which is associated with the first outlet and provides a thermally conditioned fluid with a second flow characteristic different from the first flow characteristic, adjacent to the thermally conditioned fluid from the first outlet.
Abstract:
PROBLEM TO BE SOLVED: To provide a position measuring system to a patterning device of a lithographic apparatus wherein deviation between the patterning device and a patterning device support is considered. SOLUTION: The lithographic apparatus includes an illumination system constituted to adjust a radiation beam, the patterning device support constituted to support the patterning device, the patterning device capable of imparting a pattern to a radiation beam at its cross section to form a patterned radiation beam, a substrate support constituted to hold a substrate, a projection system constituted to project the patterned radiation beam to a target of the substrate, and an encoder-type measurement system constituted to continuously determine a position quantity of the patterning device supported on the patterning device support by using a grid or a grating provided on the patterning device at least during the projection of the patterned radiation beam to a target of the substrate. COPYRIGHT: (C)2010,JPO&INPIT
Abstract:
PROBLEM TO BE SOLVED: To reduce flexibility and resulting internal deformations by increasing stiffness and/or damping of a body of an object.SOLUTION: A positioning system to position a movable object having a body includes an object position measurement system, an object actuator, and an object controller. The positioning system further includes a stiffener to increase the stiffness and/or to damp relative movements within the body of the object. The stiffener includes: one or more sensors each arranged to determine a measurement signal representative of an internal strain or relative displacement in the body; one or more actuators each arranged to exert actuation force on a part of the body; and at least one controller configured to provide, on the basis of the measurement signal of at least one of the sensors, an actuation signal to at least one of the actuators to increase the stiffness and/or to damp movements within the body.
Abstract:
PROBLEM TO BE SOLVED: To reduce flexibility and resulting internal deformations by increasing stiffness and/or damping of a body of an object.SOLUTION: A positioning system to position a movable object having a body includes an object position measurement system, an object actuator, and an object controller. The positioning system further includes a stiffener to increase the stiffness and/or to damp relative movements within the body of the object. The stiffener includes: one or more sensors each arranged to determine a measurement signal representative of an internal strain or relative displacement in the body; one or more actuators each arranged to exert actuation force on a part of the body; and at least one controller configured to provide, on the basis of the measurement signal of at least one of the sensors, an actuation signal to at least one of the actuators to increase the stiffness and/or to damp movements within the body.
Abstract:
PROBLEM TO BE SOLVED: To improve stage position measurement accuracy of a stage.SOLUTION: A position measurement system to measure a position of a movable stage includes: a reference plate; a plurality of sensors configured such that, corresponding to the position of the movable stage relative to the reference plate, at least a subset of the plurality of sensors cooperates with the reference plate to provide for each sensor in the subset respective sensor signals representative of the positions of the respective sensors relative to the reference plate; and a processor which determines from the sensor signals a stage position. When the stage is at a position where an over-determined number of sensor signals are provided by at least the subset of the sensors in operational cooperation with the reference plate, the processing device (a) determines the stage position from a subset of the over-determined number of sensor signals, and (b) corrects the sensor signal of one or more of the sensors from a discrepancy between the determined stage position and the remaining sensor signals.
Abstract:
PROBLEM TO BE SOLVED: To provide favorably an encoder type highly accurate measurement system configured to measure a position dependent signal of a movable object with almost no substantial influence of the motion of the moving object on measuring accuracy. SOLUTION: The encoder type measurement system is configured to measure the position dependent signal of the movable object and includes at least one sensor attachable onto the movable object, a sensor target attachable onto a substantially stationary frame, and an attaching device configured to attach the sensor target onto the substantially stationary frame. It further includes a compensation device configured to compensate for movement and/or deformation of a sensor target object relative to the substantially stationary frame. The compensation device may include a passive type or active type damping device and/or a feedback position control system. In a substitute embodiment, the compensation device includes a gripping device fixing the position of the sensor target object. COPYRIGHT: (C)2011,JPO&INPIT