Abstract: A lithography apparatus includes a projection optical system that projects an image of a pattern, a first support member, a second support member that is flexibly coupled to the first support member by a first flexible coupling device such that the second support member is suspended from the first support member, and a second flexible coupling device that flexibly couples the projection optical system to the second support structure. This arrangement is capable of improving the vibration characteristics of the projection optical system.

Abstract: Reticle and/or wafer stage interferometers are mounted to a supporting body that is separate from the body that supports the projection optical system of a lithography apparatus. This enables the size of the body supporting the projection optical system to be reduced so that it has more favorable dynamic characteristics.

Abstract: Methods and apparatus for controlling a stage assembly in up to six degrees of freedom using actuators which each allow for forces to be generated in a horizontal direction and a vertical direction are disclosed. According to one aspect of the present invention, a stage apparatus includes a stage assembly and a first stator arrangement. The stage assembly includes a first magnet arrangement of an actuator assembly, and the first stator arrangement is part of the actuator assembly. The first magnet arrangement cooperates with the first stator arrangement to allow the stage assembly to move relative to a first horizontal axis as well as a vertical axis.

Abstract: A mover (344) that moves a stage (238) along a first axis includes a magnetic component (354), a conductor component (356), and a sensor (366). The magnetic component (354) includes one or more magnets (354D) that are surrounded by a magnetic field. The conductor component (356) is positioned near the magnetic component (354). Further, the conductor component (356) interacts with the magnetic component (354) to generate a force when current is directed to the conductor component (356). The sensor (366) can be used for determining a first axis component of a magnetic flux of the magnetic component (354) during operation of the mover (344). Further, the sensor (366) can be used to determine a side force (365) that along a second axis that is orthogonal to the first axis that is being generated by the mover (344). With this design, the mover (344) or other components can be controlled to compensate for the side force (370).

Abstract: A reticle blind which is capable of being opened and closed at a relatively high speed and which does not cause mechanical disturbances or reaction forces. The reticle blind includes two reticle blind assemblies designed to cooperate with one another to control the passing of a laser beam of an exposure system onto a work piece, such as a semiconductor wafer or flat panel display. Each reticle blind assembly includes a linear motor having a mover and a blind configured to be positioned between a first position and a second position by the mover. Each reticle blind assembly also includes a counter mass assembly including a portion of a guide mechanism having at least one guide bar and a stator of the linear motor. The stator of the linear motor and the guide bar are integrated to form the counter mass which is configured to absorb reaction forces that are created when the blind is moved. In various embodiments, the blinds can be configured to operate in the vertical or horizontal orientation.

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: A mover (344) that moves a stage (238) along a first axis and along a second axis includes a magnetic component (354), a conductor component (356), and a control system (324). The magnetic component (354) includes one or more magnets (354D) that are surrounded by a magnetic field. The conductor component (356) is positioned near the magnetic component (354). Further, the conductor component (356) interacts with the magnetic component (354) when current is directed to the conductor component (356). The control system (224) directs current to the conductor component (356) to generate a controllable force along the first axis and a controllable force along the second axis. With this design, the same mover (344) can be used to move the stage (238) along two degrees of freedom (“DOF”). Further, the conductor component (356) including a first phase coil (364A) and a second phase coil (364B) that partly overlaps the first phase coil (364A).

Abstract: Methods and apparatus for increasing the efficiency of a voice coil motor (VCM) are disclosed. According to one aspect of the present invention, a cylindrical and radially symmetric VCM includes a plurality of sets of magnets, and a single coil. The plurality of sets of the magnets are each arranged in an array configuration, and cooperate to form a magnetic field. The coil receives current and has a plurality of windings. A first space is defined within the coil, and the plurality of sets of the magnets are arranged such that a first set of the magnets is positioned within the first space and a second set of the magnets is positioned external to the coil.

Abstract: Methods and apparatus for increasing the efficiency of a voice coil motor (VCM) are disclosed. According to one aspect of the present invention, a cylindrical and radially symmetric VCM includes a plurality of sets of magnets, and a single coil. The plurality of sets of the magnets are each arranged in an array configuration, and cooperate to form a magnetic field. The coil receives current and has a plurality of windings. A first space is defined within the coil, and the plurality of sets of the magnets are arranged such that a first set of the magnets is positioned within the first space and a second set of the magnets is positioned external to the coil.

Abstract: An apparatus for supporting an object is disclosed. The apparatus includes an air bearing coupled to an air bellows. When used in a vacuum environment, the apparatus preferably includes an air bearing housing with vacuum to remove the pressurized fluid used in the air bearing.

Abstract: Methods and apparatus for increasing the efficiency of a voice coil motor (VCM) are disclosed. According to one aspect of the present invention, a cylindrical and radially symmetric VCM includes a plurality of sets of magnets, and a single coil. The plurality of sets of the magnets are each arranged in an array configuration, and cooperate to form a magnetic field. The coil receives current and has a plurality of windings. A first space is defined within the coil, and the plurality of sets of the magnets are arranged such that a first set of the magnets is positioned within the first space and a second set of the magnets is positioned external to the coil.

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: Methods and apparatus for providing a fine stage with up to six degrees of freedom are disclosed. According to one aspect of the present invention, a stage apparatus includes a first stage assembly, a second stage assembly, and a countermass arrangement. The first stage assembly including a first component of a first actuator, and supports a second actuator arrangement. The second stage assembly is supported over the first stage assembly such that the second actuator arrangement drives the second stage assembly along a vertical axis. The countermass arrangement includes a second component of the first actuator. The first component cooperates with the second component to allow the first stage assembly to move relative to a first horizontal axis. The countermass arrangement absorbs reaction forces associated with the first and second stage assemblies.

Abstract: Devices are disclosed for placement between first and second masses for attenuating transmission of motions from one of the masses to the other. A general embodiment of such a device includes a fluid isolator and a lateral fluid bearing situated along a support axis. The fluid isolator includes a housing defining an isolator chamber pressurized with a gas at pressure Pisol. The fluid isolator is situated such that motion of the masses relative to each other along the support axis is at the fluid isolator, and lateral motion is at the lateral fluid bearing. The lateral fluid bearing includes first and second bearing surfaces that are transverse to the support axis. At least one such surface defines three channels: pressure channel, atmospheric pressure channel, and vacuum channel. In order from the isolator chamber, the pressure channel (at pressure PXYbearing?Pisol) is first, the atmospheric pressure channel (at pressure Patm) is second, and the vacuum channel (at pressure Pvac) is third.

Abstract: Methods and apparatus for accurately measuring a position of a wafer chuck which holds a wafer are disclosed. According to one aspect of the present invention, a stage apparatus includes a sensing device and a chuck. The chuck substantially directly supports an object, and includes at least one side surface that is a mirrored surface. The sensing device is arranged to cooperate with the mirrored surface to measure a position of the chuck. In one embodiment, the mirrored surface is polished onto the chuck.

Abstract: Devices are disclosed for placement between first and second masses for attenuating transmission of motions from one of the masses to the other. A general embodiment of such a device includes a fluid isolator and a lateral fluid bearing situated along a support axis. The fluid isolator includes a housing defining an isolator chamber pressurized with a gas at pressure Pisol. The fluid isolator is situated such that motion of the masses relative to each other along the support axis is at the fluid isolator, and lateral motion is at the lateral fluid bearing. The lateral fluid bearing includes first and second bearing surfaces that are transverse to the support axis. At least one such surface defines three channels: pressure channel, atmospheric pressure channel, and vacuum channel. In order from the isolator chamber, the pressure channel (at pressure PXYbearing≈Pisol) is first, the atmospheric pressure channel (at pressure Patm) is second, and the vacuum channel (at pressure Pvac) is third.

Abstract: A method for controlling and positioning a two-dimensional electric motor is disclosed. The electric motor has a coil array and a magnet array. The method controls the motor in two directions in the plane of the magnet array and about a third direction generally orthogonal to the plane. The method includes: determining currents for generating the desired forces, determining a resultant torque that would be generated from applying the determined currents, determining current adjustments to compensate for the resultant torque, and applying a current equal to the sum of the determined currents and the current adjustments to the coils to interact with the magnetic fields of the magnet array. The currents are applied to the portion of the coil array within the magnetic field of the magnet array, including those coils which are only partially within the magnetic field of the magnet array. Alternatively, the currents could be applied to all of the coils.

Abstract: A method for controlling and positioning a two-dimensional electric motor is disclosed. The electric motor has a coil array and a magnet array. The method controls the motor in two directions in the plane of the magnet array and about a third direction generally orthogonal to the plane. The method includes: determining currents for generating the desired forces, determining a resultant torque that would be generated from applying the determined currents, determining current adjustments to compensate for the resultant torque, and applying a current equal to the sum of the determined currents and the current adjustments to the coils to interact with the magnetic fields of the magnet array. The currents are applied to the portion of the coil array within the magnetic field of the magnet array, including those coils which are only partially within the magnetic field of the magnet array. Alternatively, the currents could be applied to all of the coils.

Abstract: A two-dimensional electric motor having a moving magnet and positionable in six degrees of freedom. The electric motor has a coil array and a magnet array. The magnet array has a smaller width than the coil array in the moving magnet embodiment. The invention's process of achieving motion of a coil array with respect to a magnet array in six degrees of freedom includes providing an electrical current distribution to a coils. The motion is controlled in a first direction and a vertical direction between a portion of the coils and a portion of the magnet array. The electrical current distribution has two wavelike components having a same period but approximately ninety degrees out of phase. The invention's positioning devices do not require air bearings. Instead, the suspension of the support member by magnetic attraction to the frame or by interaction of the coil array and the magnet array replace the air bearings.