Abstract: A method for determining a commutation offset for a mover (250A) of a mover assembly (220C) that moves and positions a stage (220A) relative to a stage base (220B) includes controlling the mover assembly (220C) in a closed loop fashion to maintain the position of the stage (220A) along a first axis and along a second axis with the stage (220A) levitated above the stage base (220B). The method also includes the steps of (i) directing current to a coil array (240) of the mover assembly (220C) so that the mover assembly (220C) imparts a disturbance on the stage (220A); and (ii) evaluating one or more forces generated by the mover assembly (220C) as a result of the disturbance on the stage (220A) created by the mover (250A). Further, a method for generating a compensation map (1402) includes sequentially directing a plurality of excitation signals to the control of the mover assembly (220C) and determining the control commands that result from the plurality of excitation signals.

Abstract: An exemplary stage assembly has movable stage mass and counter-mass. A stage motor is coupled to the stage mass and counter-mass such that stage-mass motion imparted by the stage motor causes a reactive motion of the counter-mass counter to the motion of the stage mass. At least one trim-motor is coupled to the counter-mass. A control system commands the trim-motor to regulate movement of the counter-mass in reaction to stage-mass motion. A PI feedback controller receives the following-error of the counter-mass and generates corresponding center-of-gravity (CG) force commands and trim-motor force commands to the trim-motor(s) to produce corrective counter-mass motion. A trim-motor force limiter receives trim-motor force commands and produces corresponding limited trim-motor force commands that are fed back as actual CG force commands to the feedback controller to modify integral terms of the feedback controller according to the limited trim-motor force commands.

Abstract: Methods, apparatus, and systems are disclosed for identifying force-ripple and/or side-forces in actuators used for moving a multiple-axis stage. The identified force-ripple and/or side-forces can be mapped, and maps of corresponding position-dependent compensation ratios useful for correcting same are obtained. The methods are especially useful for stages providing motion in at least one degree of freedom using multiple (redundant) actuators. In an exemplary method a stage member is displaced, using at least one selected actuator, multiple times over a set distance in the range of motion of the subject actuator(s). Each displacement has a predetermined trajectory and respective starting point in the range. For each displacement, respective section force-command(s) are extracted and normalized to a reference section force-command to define a section compensation-ratio.

Abstract: Electromagnetic actuators are disclosed having at least one actively cooled coil assembly. Exemplary actuators are linear and planar motors of which the cooled coil assembly has a coil having first and second main surfaces. A respective thermally conductive cooling plate is in thermal contact with at least one main surface of the coil. Defined in or on each cooling plate is a coolant passageway that conducts a liquid coolant. A primary pattern of the coolant passageway is coextensive with at least part of the main surface of the coil. The primary pattern can have a secondary pattern through which coolant flows in a manner reducing eddy-current losses. An exemplary secondary pattern is serpentine. An exemplary primary pattern is radial or has a radial aspect, such as an X-shaped pattern. The devices exhibit reduced eddy-current drag.

Abstract: Methods and apparatus for adjusting the amount of current provided to a magnetic actuator to compensate for a temperature change associated with the magnetic actuator are disclosed. According to one aspect of the present invention, an apparatus includes an actuator, which has at least one magnet and an associated force constant. The apparatus also includes a temperature sensing arrangement and a control arrangement, the temperature sensing arrangement being arranged to determine or measure a temperature of the magnet. The control arrangement adjusts the current provided to the actuator based on the temperature of the magnet. The current is adjusted to maintain a correct or desired force in light of temperature-induced variations to a force constant.

Abstract: A substrate handling structure is provided that is particularly useful with an imaging optical system that images a single reticle to a pair of imaging locations. The principles of the present invention provide substrate handling structures with new and useful metrology structures, and new and useful ways of moving substrates in relation to the imaging locations, that are designed to provide benefits in providing information as to the substrate position as a substrate is being imaged, while reducing the size of the support structure. These features are believed to be important as imaging of substrates in the 450 mm diameter range is developing.

Abstract: Methods and apparatus for providing an efficient oval coil planar motor are disclosed. According to one aspect of the present invention, an electromagnetic actuator includes at least a first coil group, at least a second coil group, and a magnet array. The first coil group includes at least a first coil that is of an elongated toroidal shape. The first coil has a first coil length and a first coil width that is approximately equal to a multiple of three times the first coil width. The second coil group includes at least a second coil that is of an elongated toroidal shape. The second coil has a second coil width and a second coil length that is approximately equal to a multiple of three times the second coil width. The second coil group is approximately adjacent to the first coil group. The magnet array is configured to cooperate with the first and second coil groups, and includes a plurality of magnets.

Abstract: Embodiments of the invention compensate for one or more effects of a stage motor in a precision stage device. A feedforward module receives an input signal corresponding to the effect of the motor and generates a feedforward control signal that can be used to modify a motor control signal to compensate for the effect of the motor. In some embodiments, a control system is provided to compensate for a back-electromotive force generated by a motor, while in other embodiments, a control system may compensate for an inductive effect of a motor. Embodiments of the invention may be useful in precision stage devices, for example, lithography devices such as steppers and scanners.

Abstract: A mover (344) moving a stage (238) along a first axis and about a second axis includes a magnetic component (454), and a conductor component (456). The magnetic component (454) includes one or more magnets (454D) that are surrounded by a magnetic field. The conductor component (456) is positioned near the magnetic component (454) in the magnetic field. Further, the conductor component (456) interacts with the magnetic component (454) when current is directed to the conductor component (456) to generate a controlled force along the first axis, and a controlled moment about the second axis. Additionally, the conductor component (456) interacts with the magnetic component (454) to generate a controlled force along a third axis that is perpendicular to the first axis and the second axis when current is directed to the conductor component (456).

Abstract: According to one aspect of the present invention, a motor arrangement includes at least one coil, a cover plate, and a shield layer. The at least one coil has a first side and a second side. The cover plate is positioned substantially over the first side of the at least one coil at a distance from the at least one coil. The shield layer is positioned between the first side of the at least one coil and the cover plate, and has a top surface. The top surface contacts the cover plate, and includes a liquid and a gas that form a mixture and cause the top surface to have a substantially constant temperature.

Abstract: A planar motor (32) for positioning a stage (44) along a first axis, and along a second axis that is perpendicular to the first axis includes a conductor array (52) and a magnet array (34). The conductor array (52) includes at least one conductor (256). The magnet array (34) is positioned near the conductor array (52) and is spaced apart from the conductor array (52) along a third axis that is perpendicular to the first axis and the second axis. The magnet array (34) includes a first magnet unit (264) having a first diagonal magnet (D1) with a diagonal magnetization direction (268) that is diagonal to the first axis, the second axis and the third axis. This leads to strong magnetic fields above the magnet array (34) and strong force generation capability. Further, the planar motor (32) provided herein has less stray magnetic fields that extend beyond the magnet array (34) than a comparable prior art planar motor.

Abstract: A catadioptric optical imaging system and method is provided, in which up to four (4) reticles are imaged to a single imaging location (e.g. for imaging substrates), in a manner designed to provide high throughput, with a relatively high resolution, and with substrates whose size may approach 450 mm.

Abstract: Methods and apparatus for shielding a reticle within an illumination system are disclosed. According to one aspect of the present invention, a blind arrangement for shielding an object such as a reticle includes a coil assembly which has at least one coil, an air supply that supplies air, and a first blind portion. The first blind portion includes at least one magnet and is not in physical contact with the coil. The first blind portion is supported at a distance from the coil by the air, and the coil assembly cooperates with the magnet to cause the first blind portion to move. The first blind portion shields the object when the first blind portion is in a first position.

Abstract: New and useful concepts for an imaging optical system configured to simultaneously image a reticle to a pair of imaging locations are provided, where the imaging optics comprise a pair of arms, each of which includes catadioptric imaging optics. In addition, the imaging optics are preferably designed to image a reticle simultaneously to the pair of imaging locations, at a numerical aperture of at least 1.3, and without obscuration of light by the imaging optics.

Abstract: A new and useful optical imaging process is provided for imaging of a plurality of substrates, in a manner that makes efficient use of an optical imaging system with the capability to image a single reticle to a pair of imaging locations, and addresses the types of substrate stage movement patterns to accomplish such imaging in an efficient and effective manner. At least three substrates are imaged by moving their substrate stages in patterns whereby (i) two of the substrates are completely imaged at respective imaging locations, (ii) a substrate on at least one of the three stages is partially imaged at one imaging location and then partially imaged at the other imaging location, and (iii) the movement of the stages of the three substrates is configured to avoid movement of the stages of the three substrates in paths that would cause interference between movement of any one substrate stage with movement of any of the other substrate stages.

Abstract: Methods and apparatus for enabling a coil to be used to provide a net force along more than one axis are disclosed. According to one aspect of the present invention, an actuator includes a magnet assembly and a coil assembly. The coil assembly moves at least partially within the magnet arrangement, and includes a top coil half and a bottom coil half. The top coil half and the bottom coil half are independently controllable such that a first current applied to the top coil half may be independently applied from a second current applied to the bottom coil half.

Abstract: An exposure apparatus (10) for transferring a mask pattern (452) from a mask (12) to a substrate (14) includes an illumination system (18), a mask stage assembly (22), a substrate stage assembly (24), and a control system (28). The substrate (14) includes a first site (1) and a second site (2) that are adjacent to each other and that are aligned with each other along a first axis. The illumination system (18) generates an illumination beam (35) that is directed at the mask (12). The mask stage assembly (22) retains and positions the mask (12) relative to the illumination beam (35). The substrate stage assembly (24) retains and positions the substrate (14). The control system (28) controls the illumination system (18) and the substrate stage assembly (24) so that the mask pattern (452) is sequentially transferred to the first site (1) and then the second site (2) while the substrate stage assembly (24) is moving the substrate (24) in a first mask direction along the first axis.

Abstract: An exposure apparatus (210) for transferring a mask pattern (346) from a mask (212) to a substrate (214) includes a first site (315) having a first site dimension (348) along a first axis and a second site dimension (350) along a second axis that is perpendicular to the first axis. The second site dimension (350) is larger than the first site dimension (348). The exposure apparatus (210) includes an illumination system (218), a mask stage assembly (222), a substrate stage assembly (224), and a control system (228). The illumination system (218) generates an illumination beam (235) that is directed at the mask (212). The mask stage assembly (222) retains and positions the mask (212) along the first axis relative to the illumination beam (235). The substrate stage assembly (224) retains and positions the substrate (214) along the first axis.

Abstract: An exposure apparatus (10) for transferring a mask pattern (358) from a mask (12) to a substrate (14) includes a mask retainer (44), a substrate stage assembly (24), and an illumination system (18). The mask retainer (44) retains the mask (12). The substrate stage assembly (24) retains and positions the substrate (14). The illumination system (18) generates an illumination beam (31) that moves along a beam scan axis (35) relative to the mask (12) to scan at least a portion of the mask pattern (358). The beam scan axis (35) is substantially parallel to the mask pattern (358). The illumination system (18) can include an illumination source (32) that generates the illumination beam (31) and an illumination optical assembly (34) that guides the illumination beam (31). The illumination optical assembly (34) moves the illumination beam (31) relative to the mask (12) so that the illumination beam (31) scans substantially the entire mask pattern (358).

Abstract: A mover (344) moving a stage (238) along a first axis, along a second axis and along a third axis includes a magnetic component (354), a conductor component (356), and a control system (324). The magnetic component (354) includes a plurality of magnets (354D) that are surrounded by a magnetic field. The conductor component (356) is positioned near the magnetic component (354) in the magnetic field. Further, the conductor component (356) interacts with the magnetic component (354) when current is directed to the conductor component (356) to generate a controllable force along the first axis, a controllable force along the second axis, and a controllable force along the third axis. The conductor component (356) can include a split coil design, having a first conductor array (356A) and a second conductor array (356B) that is positioned substantially adjacent to the first conductor array (356A).