Object force application system

Abstract

A system includes a chuck and an object force application system mounted on the chuck. The object force application system includes mounts, actuators, mount force actuation devices, object force actuation devices, a measuring system, and a control system. Each of the actuators and each of the mount force actuation devices are coupled to corresponding mounts. The object force actuation devices are located on opposite edges of an object and adjacent to corresponding mount force actuation devices such that gaps are formed between each object force actuation device adjacent to a mount force actuation device. The measuring system measures the gaps. The control system adjusts a voltage or a current supplied to the mount force actuation devices or moves the actuators to adjust forces produced between the mount force actuation devices and the object force actuation devices based on the measuring, such that the gaps are maintained within a predetermined tolerance.

Description

OBJECT FORCE APPLICATION SYSTEMCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority of US application 63 / 674,588 which was filed on July 23, 2024 and which is incorporated herein in its entirety by reference.FIELD

[0002] The present disclosure relates to object support structures, for example, an object support structure on an actuated stage used in lithographic apparatuses and systems.BACKGROUND

[0003] A lithographic apparatus is a machine constructed to apply a desired pattern onto a substrate. A lithographic apparatus can be used, for example, in the manufacture of integrated circuits (ICs). A lithographic apparatus can, for example, project a pattern of a patterning device (e.g., a mask, a reticle) onto a layer of radiation-sensitive material (photoresist or simply “resist”) provided on a substrate.

[0004] To project a pattern on a substrate a lithographic apparatus can use electromagnetic radiation. The wavelength of this radiation determines the minimum size of features which can be formed on the substrate. A lithographic apparatus, which uses extreme ultraviolet (EUV) radiation, having a wavelength within the range 4-20 nm, for example 6.7 nm or 13.5 nm, can be used to form smaller features on a substrate than a lithographic apparatus which uses, for example, radiation with a wavelength of 193 nm.

[0005] A lithographic system can output only a finite number of fabricated devices in a given timeframe. Fast scanning of objects such as, for example, reticles or wafers, can improve the speed of fabrication. When performing fast scanning, an actuated stage quickly accelerates to reach the scan velocity, then at the end of the scan, it quickly decelerates to zero, reverses direction and accelerates in the opposite direction to reach the scan velocity. During the acceleration and deceleration portions of the scan, an object disposed on the actuated stage can experience a large inertial force that causes the object, or a portion of that object, to slip from its aligned position at a nanometer level on the actuated stage. Such object slip can result in a misaligned device pattern, or can damage the object and / or the actuated stage.SUMMARY

[0006] Accordingly, it is desirable to reduce or prevent object slip during high accelerations and / or decelerations in a reliable, uniform, and efficient manner. For example, a reticle stage can include devices to adjust and / or maintain a position of a reticle during acceleration and / or deceleration of the reticle stage.In another example, a wafer stage can include devices to adjust and / or maintain a position of a wafer or a mirror block during acceleration and / or deceleration of the wafer stage.

[0007] In some aspects, a system can include a chuck and an object force application system mounted on the chuck. The object force application system can include mounts. The object force application system can further include actuators each coupled to a corresponding one of the mounts. The object force application system can further include mount force actuation devices each coupled to a corresponding one of the mounts. The object force application system can further include first and second object force actuation devices on respective first and second opposite edges of an object. Each of the first and second object force actuation devices can be located adjacent to and forms a gap with respect to at least a corresponding one of the mount force actuation devices. The object force application system can further include a measuring system configured to measure the gaps. The object force application system can further include a control system configured to adjust a voltage or a current supplied to the mount force actuation devices or to move the actuators to adjust forces produced between each of the first and second object force actuation devices and the corresponding at least one of the mount force actuation devices based on the measuring, such that the gaps are maintained within a predetermined tolerance.

[0008] In some aspects, a system can include a chuck and an electrostatic object force application system mounted on the chuck. The electrostatic object force application system can include mounts. The electrostatic object force application system can further include actuators coupled to a corresponding one of the mounts. The electrostatic object force application system can further include mount electrostatic actuation devices each coupled to a corresponding one of the mounts. The electrostatic object force application system can further include first and second object electrostatic actuation devices on respective first and second opposite edges of an object. Each of the first and second object electrostatic actuation devices can be located adjacent to and forms a gap with respect to at least a corresponding one of the mount electrostatic actuation devices. The electrostatic object force application system can further include a measuring system configured to measure the gaps. The electrostatic object force application system can further include a control system configured to adjust a voltage or a current supplied to the mount electrostatic actuation devices or to move the actuators to adjust forces produced between each of the first and second object electrostatic actuation devices and the corresponding at least one of the mount electrostatic actuation devices based on the measuring, such that the gaps are maintained within a predetermined tolerance.

[0009] In some aspects, a system can include a chuck and an electromagnetic object force application system mounted on the chuck. The electromagnetic object force application system can include mounts. The electromagnetic object force application system can further include mount electromagnetic actuation devices each coupled to a corresponding one of the mounts. The electromagnetic object force applicationsystem can further include first and second object electromagnetic actuation devices on respective first and second opposite edges of an object. Each of the first and second object electromagnetic actuation devices can be located adjacent to and forms a gap with respect to at least a corresponding one of the mount electromagnetic actuation devices. The electromagnetic object force application system can further include a measuring system configured to measure the gaps. The electromagnetic object force application system can further include a control system configured adjust a voltage, a flux, or a current supplied to the mount electromagnetic actuation devices to adjust forces produced between each of the first and second object electromagnetic actuation devices and the corresponding at least one of the mount electromagnetic actuation devices based on the measuring, such that the gaps are maintained within a predetermined tolerance.

[0010] Further features of various aspects of the present disclosure are described in detail below with reference to the accompanying drawings. It is noted that the present disclosure is not limited to the specific aspects described herein. Such aspects are presented herein for illustrative purposes only. Additional aspects will be apparent to those skilled in the relevant art(s) based on the teachings contained herein.BRIEF DESCRIPTION OF THE DRAWINGS / FIGURES

[0011] The accompanying drawings, which are incorporated herein and form part of the specification, illustrate the present disclosure and, together with the description, further serve to explain the principles of the present disclosure and to enable those skilled in the relevant art(s) to make and use aspects described herein.

[0012] FIG. 1A shows a reflective lithographic apparatus, according to some aspects.

[0013] FIG. IB shows a transmissive lithographic apparatus, according to some aspects.

[0014] FIG. 1C shows a lithographic cell, according to some aspects.

[0015] FIGS. 2 and 3 show a reticle stage, according to some aspects.

[0016] FIG. 4 shows a reticle exchange apparatus, according to some aspects.

[0017] FIG. 5 shows an object force application system, according to some aspects.

[0018] FIG. 6 shows a method for operating an object force application system, according to some aspects.

[0019] FIGS. 7A and 7B show an electrostatic object force application system, according to some aspects.

[0020] FIG. 8 shows a method for operating an electrostatic object force application system, according to some aspects.

[0021] FIGS. 9A and 9B show an electromagnetic object force application system, according to some aspects.

[0022] FIG. 10 shows a method for operating an electromagnetic object force application system, according to some aspects.

[0023] The features of the present disclosure will become more apparent from the detailed description set forth below when taken in conjunction with the drawings, in which like reference characters identify corresponding elements throughout. In the drawings, like reference numbers generally indicate identical, functionally similar, and / or structurally similar elements. Additionally, generally, the left-most digit(s) of a reference number identifies the drawing in which the reference number first appears. Unless otherwise indicated, the drawings provided throughout the disclosure should not be interpreted as to-scale drawings.DETAILED DESCRIPTION

[0024] The aspects described herein, and references in the specification to “one aspect,” “an aspect,” “an exemplary aspect,” “an example aspect,” etc., indicate that the aspects described can include a particular feature, structure, or characteristic, but every aspect may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same aspect. Further, when a particular feature, structure, or characteristic is described in connection with an aspect, it is understood that it is within the knowledge of those skilled in the art to effect such feature, structure, or characteristic in connection with other aspects whether or not explicitly described.

[0025] Spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “on,” “upper” and the like, can be used herein for ease of description to describe one element or feature’s relationship to another element(s) or feature(s) as illustrated in the figures. The spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. The apparatus can be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein can likewise be interpreted accordingly.

[0026] The terms “about,” “approximately,” or the like can be used herein to indicate the value of a given quantity that can vary based on a particular technology. Based on the particular technology, the terms “about,” “approximately,” or the like can indicate a value of a given quantity that varies within, for example, 10-30% of the value (e.g., ±10%, ±20%, or ±30% of the value).

[0027] Aspects of the present disclosure can be implemented in hardware, firmware, software, or any combination thereof. Aspects of the disclosure can also be implemented as instructions stored on a computer-readable medium, which can be read and executed by one or more processors. A machine- readable medium can include any mechanism for storing or transmitting information in a form readable by a machine (e.g., a computing device). For example, a machine-readable medium can include read only memory (ROM); random access memory (RAM); magnetic disk storage media; optical storage media; flash memory devices; electrical, optical, acoustical or other forms of propagated signals (e.g., carrier waves, infrared signals, digital signals, etc.), and others. Furthermore, firmware, software, routines, and / or instructions can be described herein as performing certain actions. However, it should be appreciated thatsuch descriptions are merely for convenience and that such actions result from computing devices, processors, controllers, or other devices executing the firmware, software, routines, instructions, etc. The term “machine -readable medium” can be interchangeable with similar terms, for example, “computer program product,” “computer-readable medium,” “non-transitory computer-readable medium,” or the like. The term “non-transitory” can be used herein to characterize one or more forms of computer readable media except for a transitory, propagating signal.

[0028] Before describing such aspects in more detail, however, it is instructive to present an example environment in which aspects of the present disclosure can be implemented.

[0029] Example Lithographic Systems

[0030] FIGS. 1A and IB show a lithographic apparatus 100 and a lithographic apparatus 100’, respectively, in which aspects of the present disclosure can be implemented. Lithographic apparatus 100 and lithographic apparatus 100’ each include the following: an illumination system (illuminator) IL configured to condition a radiation beam B (for example, deep ultra violet or extreme ultra violet radiation); a support structure (for example, a mask table) MT configured to support a patterning device (for example, a mask, a reticle, or a dynamic patterning device) MA and connected to a first positioner PM configured to accurately position the patterning device MA; and, a substrate table (for example, a wafer table) WT configured to hold a substrate (for example, a resist coated wafer) W and connected to a second positioner PW configured to accurately position the substrate W. Lithographic apparatus 100 and 100’ also have a projection system PS configured to project a pattern imparted to the radiation beam B by patterning device MA onto a target portion (for example, comprising one or more dies) C of the substrate W. In lithographic apparatus 100, the patterning device MA and the projection system PS are reflective. In lithographic apparatus 100’, the patterning device MA and the projection system PS are transmissive.

[0031] The illumination system IL can include various types of optical components, such as refractive, reflective, catadioptric, magnetic, electromagnetic, electrostatic, or other types of optical components, or any combination thereof, for directing, shaping, or controlling the radiation beam B.

[0032] The support structure MT holds the patterning device MA in a manner that depends on the orientation of the patterning device MA with respect to a reference frame, the design of at least one of the lithographic apparatus 100 and 100’, and other conditions, such as whether or not the patterning device MA is held in a vacuum environment. The support structure MT can use mechanical, vacuum, electrostatic, or other clamping techniques to hold the patterning device MA. The support structure MT can be a frame or a table, for example, which can be fixed or movable. By using sensors, the support structure MT can ensure that the patterning device MA is at a desired position, for example, with respect to the projection system PS.

[0033] The term “patterning device” MA should be broadly interpreted as referring to any device that can be used to impart a radiation beam B with a pattern in its cross-section, such as to create a pattern in the target portion C of the substrate W. The pattern imparted to the radiation beam B can correspond to a particular functional layer in a device being created in the target portion C to form an integrated circuit.

[0034] The patterning device MA can be transmissive (as in lithographic apparatus 100’ of FIG. IB) or reflective (as in lithographic apparatus 100 of FIG. 1A). Examples of patterning devices MA include reticles, masks, programmable mirror arrays, or programmable LCD panels. Masks are well known in lithography, and include mask types such as binary, alternating phase shift, or attenuated phase shift, as well as various hybrid mask types. An example of a programmable mirror array employs a matrix arrangement of small mirrors, each of which can be individually tilted so as to reflect an incoming radiation beam in different directions. The tilted mirrors impart a pattern in the radiation beam B, which is reflected by a matrix of small mirrors.

[0035] The term “projection system” PS can encompass any type of projection system, including refractive, reflective, catadioptric, magnetic, electromagnetic and electrostatic optical systems, or any combination thereof, as appropriate for the exposure radiation being used, or for other factors, such as the use of an immersion liquid on the substrate W or the use of a vacuum. A vacuum environment can be used for EUV or electron beam radiation since other gases can absorb too much radiation or electrons. A vacuum environment can therefore be provided to the whole beam path with the aid of a vacuum wall and vacuum pumps.

[0036] Lithographic apparatus 100 and / or lithographic apparatus 100’ can be of a type having two (dual stage) or more substrate tables WT (and / or two or more mask tables). In such “multiple stage” machines, the additional substrate tables WT can be used in parallel, or preparatory steps can be carried out on one or more tables while one or more other substrate tables WT are being used for exposure. In some situations, the additional table may not be a substrate table WT.

[0037] The lithographic apparatus can also be of a type wherein at least a portion of the substrate can be covered by a liquid having a relatively high refractive index, e.g., water, so as to fill a space between the projection system and the substrate. An immersion liquid can also be applied to other spaces in the lithographic apparatus, for example, between the mask and the projection system. Immersion techniques are well known in the art for increasing the numerical aperture of projection systems. The term “immersion” as used herein does not mean that a structure, such as a substrate, must be submerged in liquid. For example, a liquid can be located between the projection system and the substrate during exposure.

[0038] Referring to FIGS. 1A and IB, the illuminator IL receives a radiation beam from a radiation source SO. The source SO and the lithographic apparatus 100, 100’ can be separate physical entities, for example, when the source SO is an excimer laser. In such cases, the source SO is not considered to form part of thelithographic apparatus 100 or 100’, and the radiation beam B passes from the source SO to the illuminator IL with the aid of a beam delivery system BD (in FIG. IB) including, for example, suitable directing mirrors and / or a beam expander. In other cases, the source SO can be an integral part of the lithographic apparatus 100, 100’, for example, when the source SO is a mercury lamp. A radiation system can comprise the source SO, the illuminator IL, and / or the beam delivery system BD.

[0039] The illuminator IL can include an adjuster AD (in FIG. IB) for adjusting the angular intensity distribution of the radiation beam. Generally, at least the outer and / or inner radial extent (commonly referred to as “n-outer” and “n-inner,” respectively) of the intensity distribution in a pupil plane of the illuminator can be adjusted. In addition, the illuminator IL can comprise various other components (in FIG. IB), such as an integrator IN and a condenser CO. The illuminator IL can be used to condition the radiation beam B to have a desired uniformity and intensity distribution in its cross section.

[0040] Referring to FIG. 1 A, the radiation beam B is incident on the patterning device (for example, mask) MA, which is held on the support structure (for example, mask table) MT, and is patterned by the patterning device MA. In lithographic apparatus 100, the radiation beam B is reflected from the patterning device (for example, mask) MA. After being reflected from the patterning device (for example, mask) MA, the radiation beam B passes through the projection system PS, which focuses the radiation beam B onto a target portion C of the substrate W. With the aid of the second positioner PW and position sensor IF2 (for example, an interferometric device, linear encoder, or capacitive sensor), the substrate table WT can be moved accurately (for example, so as to position different target portions C in the path of the radiation beam B). Similarly, the first positioner PM and another position sensor IF 1 can be used to accurately position the patterning device (for example, mask) MA with respect to the path of the radiation beam B. Patterning device (for example, mask) MA and substrate W can be aligned using mask alignment marks Ml, M2 and substrate alignment marks PI, P2.

[0041] Referring to FIG. IB, the radiation beam B is incident on the patterning device (for example, mask MA), which is held on the support structure (for example, mask table MT), and is patterned by the patterning device. Having traversed the mask MA, the radiation beam B passes through the projection system PS, which focuses the beam onto a target portion C of the substrate W. The projection system has a pupil conjugate PPU to an illumination system pupil IPU. Portions of radiation emanate from the intensity distribution at the illumination system pupil IPU and traverse a mask pattern without being affected by diffraction at the mask pattern and create an image of the intensity distribution at the illumination system pupil IPU.

[0042] The projection system PS projects an image of the mask pattern MP, where the image is formed by diffracted beams produced from the mark pattern MP by radiation from the intensity distribution, onto a photoresist layer coated on the substrate W. For example, the mask pattern MP can include an array of linesand spaces. A diffraction of radiation at the array and different from zeroth order diffraction generates diverted diffracted beams with a change of direction in a direction perpendicular to the lines. Undiffracted beams (i.e., so-called zeroth order diffracted beams) traverse the pattern without any change in propagation direction. The zeroth order diffracted beams traverse an upper lens or upper lens group of the projection system PS, upstream of the pupil conjugate PPU of the projection system PS, to reach the pupil conjugate PPU. The portion of the intensity distribution in the plane of the pupil conjugate PPU and associated with the zeroth order diffracted beams is an image of the intensity distribution in the illumination system pupil IPU of the illumination system IU. The aperture device PD, for example, is disposed at or substantially at a plane that includes the pupil conjugate PPU of the projection system PS.

[0043] The projection system PS is arranged to capture (e.g., using a lens or lens group U) the zeroth order diffracted beams, first order diffracted beams, and / or higher order diffracted beams (not shown). In some aspects, dipole illumination for imaging line patterns extending in a direction perpendicular to a line can be used to utilize the resolution enhancement effect of dipole illumination. For example, first-order diffracted beams interfere with corresponding zeroth-order diffracted beams at the level of the wafer W to create an image of the line pattern MP at highest possible resolution and process window (i.e., usable depth of focus in combination with tolerable exposure dose deviations). In some aspects, astigmatism aberration can be reduced by providing radiation poles (not shown) in opposite quadrants of the illumination system pupil IPU. Further, in some aspects, astigmatism aberration can be reduced by blocking the zeroth order beams in the pupil conjugate PPU of the projection system associated with radiation poles in opposite quadrants. This is described in more detail in US 7,511,799 B2, issued Mar. 31, 2009, which is incorporated by reference herein in its entirety.

[0044] With the aid of the second positioner PW and position sensor IFD (for example, an interferometric device, linear encoder, or capacitive sensor), the substrate table WT can be moved accurately (for example, so as to position different target portions C in the path of the radiation beam B) . Similarly, the first positioner PM and another position sensor (not shown in FIG. IB) can be used to accurately position the mask MA with respect to the path of the radiation beam B (for example, after mechanical retrieval from a mask library or during a scan).

[0045] In general, movement of the mask table MT can be realized with the aid of a long-stroke module (coarse positioning) and a short-stroke module (fine positioning), which form part of the first positioner PM. Similarly, movement of the substrate table WT can be realized using a long-stroke module and a shortstroke module, which form part of the second positioner PW. In the case of a stepper (as opposed to a scanner), the mask table MT can be connected to a short-stroke actuator or can be fixed. Mask MA and substrate W can be aligned using mask alignment marks Ml, M2, and substrate alignment marks Pl, P2. Although the substrate alignment marks (as illustrated) occupy dedicated target portions, they can belocated in spaces between target portions (known as scribe-lane alignment marks). Similarly, in situations in which more than one die is provided on the mask MA, the mask alignment marks can be located between the dies.

[0046] Mask table MT and patterning device MA can be in a vacuum chamber V, where an in-vacuum robot IVR can be used to move patterning devices such as a mask in and out of vacuum chamber. Alternatively, when mask table MT and patterning device MA are outside of the vacuum chamber, an out- of-vacuum robot can be used for various transportation operations, similar to the in-vacuum robot IVR. Both the in-vacuum and out-of-vacuum robots can be calibrated for a smooth transfer of any payload (e.g., mask) to a fixed kinematic mount of a transfer station.

[0047] The lithographic apparatus 100 and 100’ can be used in at least one of the following modes:1. In step mode, the support structure (for example, mask table) MT and the substrate table WT are kept essentially stationary, while an entire pattern imparted to the radiation beam B is projected onto a target portion C at one time (i.e., a single static exposure). The substrate table WT is then shifted in the X and / or Y direction so that a different target portion C can be exposed.2. In scan mode, the support structure (for example, mask table) MT and the substrate table WT are scanned synchronously while a pattern imparted to the radiation beam B is projected onto a target portion C (i.e., a single dynamic exposure). The velocity and direction of the substrate table WT relative to the support structure (for example, mask table) MT can be determined by the (de-)magnification and image reversal characteristics of the projection system PS.3. In another mode, the support structure (for example, mask table) MT is kept substantially stationary holding a programmable patterning device, and the substrate table WT is moved or scanned while a pattern imparted to the radiation beam B is projected onto a target portion C. A pulsed radiation source SO can be employed and the programmable patterning device is updated as needed after each movement of the substrate table WT or in between successive radiation pulses during a scan. This mode of operation can be readily applied to maskless lithography that utilizes a programmable patterning device, such as a programmable mirror array.

[0048] Combinations and / or variations on the described modes of use or entirely different modes of use can also be employed.

[0049] In some aspects, lithographic apparatus 100 includes an extreme ultraviolet (EUV) source, which is configured to generate a beam of EUV radiation for EUV lithography. In general, the EUV source is configured in a radiation system, and a corresponding illumination system is configured to condition the EUV radiation beam of the EUV source.

[0050] In some aspects, lithographic apparatus 100’ includes a deep ultraviolet (DUV) source, which is configured to generate a beam of DUV radiation for DUV lithography. In general, the DUV source isconfigured in a radiation system, and a corresponding illumination system is configured to condition the DUV radiation beam of the DUV source.

[0051] Example Lithographic Cell

[0052] FIG. 1C shows a lithographic cell 102, also sometimes referred to a lithocell or cluster, according to some aspects. Lithographic apparatuses 100 or 100’ can form part of lithographic cell 100. Lithographic cell 102 can also include one or more apparatuses to perform pre- and post-exposure processes on a substrate. Conventionally these include spin coaters SC to deposit resist layers, developers DE to develop exposed resist, chill plates CH, and bake plates BK. A substrate handler, or robot, RO picks up substrates from input / output ports I / O I, I / O2, moves them between the different process apparatuses and delivers them to the loading bay LB of the lithographic apparatus 100 or 100’. These devices, which are often collectively referred to as the track, are under the control of a track control unit TCU, which is itself controlled by a supervisory control system SCS, which also controls the lithographic apparatus via lithography control unit LACU. Thus, the different apparatuses can be operated to maximize throughput and processing efficiency.

[0053] Example Reticle Stage

[0054] FIGS. 2 and 3 show a reticle stage 200, according to some aspects. Reticle stage 200 can include top stage surface 202, bottom stage surface 204, side stage surfaces 206, and clamp 300. In some aspects, reticle stage 200 with clamp 300 can be implemented in lithographic apparatus 100 and / or lithographic apparatus 100’. For example, reticle stage 200 can be support structure MT in lithographic apparatus 100 and / or lithographic apparatus 100’. In some aspects, clamp 300 can be disposed on top stage surface 202. For example, as shown in FIG. 2, clamp 300 can be disposed at a center of top stage surface 202 with clamp frontside 302 facing perpendicularly away from top stage surface 202.

[0055] In some lithographic apparatuses, for example, lithographic apparatus 100 and / or lithographic apparatus 100’, a reticle stage 200 with a clamp 300 can be used to hold and position a reticle 408 for scanning or patterning operations. In one example, the reticle stage 200 can rely on powerful drives, large balance masses, and heavy frames to support it. In one example, the reticle stage 200 can have a large inertia and can weigh over 500 kg to propel and position a reticle 408 weighing about 0.5 kg. To accomplish reciprocating motions of the reticle 408, which are typically found in lithographic scanning or patterning operations, accelerating and decelerating forces can be provided by linear motors that drive the reticle stage 200.

[0056] In some aspects, as shown in FIGS. 2 and 3, reticle stage 200 can include first encoder 212 and second encoder 214 for positioning operations. For example, first and second encoders 212 and 214 can be interferometers. First encoder 212 can be attached along a first direction, for example, a transverse direction (i.e., X-direction) of reticle stage 200. And second encoder 214 can be attached along a second direction,for example, a longitudinal direction (i.e., Y-direction) of reticle stage 200. In some aspects, as shown in FIGS. 2 and 3, first encoder 212 can be orthogonal to second encoder 214.

[0057] As shown in FIGS. 2 and 3, reticle stage 200 can include clamp 300. Clamp 300 is configured to hold reticle 408 in a fixed plane on reticle stage 200. Clamp 300 includes clamp frontside 302 and can be disposed on top stage surface 202. In some aspects, clamp 300 can use mechanical, vacuum, electrostatic, or other suitable clamping techniques to hold and secure an object. In some aspects, clamp 300 can be an electrostatic clamp, which can be configured to electrostatically clamp (i.e., hold) an object, for example, reticle 408 in a vacuum environment. For EUV generation performed in a vacuum environment, it can be difficult to use vacuum clamps to clamp a mask or reticle. Instead, electrostatic clamp(s) can be used. For example, clamp 300 can include an electrode, a resistive layer on the electrode, a dielectric layer on the resistive layer, and burls projecting from the dielectric layer. In use, a voltage can be applied to clamp 300, for example, several kV. And current can flow through the resistive layer, such that the voltage at an upper surface of the resistive layer will substantially be the same as the voltage of the electrode and generate an electric field. Also, a Coulomb force, attractive force between electrically opposite charged particles, will attract an object to clamp 300 and hold the object in place. In some aspects, clamp 300 can be a rigid material, for example, a metal, a dielectric, a ceramic, or a combination thereof.

[0058] Example Reticle Exchange Apparatus

[0059] FIG. 4 shows a reticle exchange apparatus 401, according to some aspects. Reticle exchange apparatus 401 can be configured to minimize reticle exchange time, particle generation, and contact forces or stresses from clamp 300 and / or reticle 408 to reduce damage to clamp 300 and reticle 408 and increase overall throughput in a reticle exchange process, for example, in a lithographic apparatus 100 and / or lithographic apparatus 100’.

[0060] Reticle exchange apparatus 401 can include reticle stage 200, clamp 300, and in-vacuum robot 400. In-vacuum robot 400 can include reticle handler 402.

[0061] In some aspects, reticle handler 402 can be a rapid exchange device (RED), which is configured to efficiently rotate and minimize reticle exchange time. For example, reticle handler 402 can save time by moving multiple reticles from one position to another substantially simultaneously, instead of serially.

[0062] In some aspects, reticle handler 402 can include one or more reticle handler arms 404. Reticle handler arm 404 can include reticle baseplate 406. Reticle baseplate 406 can be configured to hold an object, for example, reticle 408.

[0063] In some aspects, reticle baseplate 406 can be an extreme ultraviolet inner pod (EIP) for a reticle. In some aspect, reticle baseplate 406 includes reticle baseplate frontside 407, and reticle 408 includes reticle backside 409.

[0064] In some aspects, reticle baseplate 406 can hold reticle 408 such that reticle baseplate frontside 407 and reticle backside 409 each face top stage surface 202 and clamp frontside 302. For example, reticle baseplate frontside 407 and reticle backside 409 can be facing perpendicularly away from top stage surface 202 and clamp frontside 302.

[0065] In some aspects, as shown in FIG. 4, reticle handler arms 404 can be arranged symmetrically about reticle handler 402. For example, reticle handler arms 404 can be spaced from each other by about 90 degrees, 120 degrees, or 180 degrees. In some aspects, reticle handler arms 404 can be arranged asymmetrically about reticle handler 402. For example, two reticle handler arms 404 can be spaced from each other by about 135 degrees, while another two reticle handler arms 404 can be spaced from each other by about 90 degrees.

[0066] In some aspects, during a reticle exchange process, reticle stage 200 with clamp 300 can be adjusted in a multi-stage movement (e.g., long stroke stage (coarse motion), short stroke stage (fine motion)).

[0067] Example Object Force Application System

[0068] FIG. 5 shows an object force application system 504 as part of a system 500, according to some aspects. In some aspects, system 500 can include a chuck 502 and an object force application system 504 mounted on chuck 502. In some aspects, system 500 can be implemented in lithographic apparatus 100 and / or lithographic apparatus 100’. For example, system 500 can be implemented within support structure MT in lithographic apparatus 100 and / or lithographic apparatus 100’. In another example, system 500 can be implemented within reticle stage 200 in lithographic apparatus 100 and / or lithographic apparatus 100’. In another example, system 500 can be implemented within substrate table WT (e.g., a wafer table) in lithographic apparatus 100 and / or lithographic apparatus 100’.

[0069] In some aspects, chuck 502 can be an actuated structure (e.g., for coarse motion of an object 518). The motion of chuck 502 can be limited to an axis (e.g., Y-axis) using guide rails or a contactless method (e.g., magnetic levitation) (guide devices not shown). In one example, chuck 502 can move in a first direction 526 along the Y-axis and in a second direction 528 opposite to first direction 526 along the Y- axis. The coordinate axes X and Y are provided as an example and are not to be construed as limiting.

[0070] In some aspects, object force application system 504 can include one or more actuation systems (collectively, actuation systems 505), one or more object force actuation devices (collectively, object force actuation devices 512), a measuring system 514, and a control system 516. In some aspects, each of actuation systems 505 can include one or more mounts (collectively, mounts 506), one or more actuators (collectively, actuators 508), and one or more mount force actuation devices (collectively, mount force actuation devices 510).

[0071] For convenience of illustration, in the example aspect shown in FIG. 5, object force application system 504 can include two actuation systems 505a, 505b. Actuation system 505a can be located adjacentto first edge 520a of object 518 and actuation system 505b can be located adjacent to second edge 520b of object 518. While FIG. 5 shows two actuation systems 505a, 505b, each located adjacent to opposing sides of object 518, a person skilled in the art would recognize that object force application system 504 can include only one actuation system 505 that is located adjacent to one side of object 518. For example, in one aspect, object force application system 504 can include only actuation system 505a located adjacent to first edge 520a or can include only actuation system 505b located adjacent to second edge 520b.

[0072] For convenience of illustration, in the example aspect shown in FIG. 5, each of actuation systems 505a, 505b can include two mounts 506, two actuators 508, and two mount force actuation devices 510. For example, actuation system 505a can include mounts 506a, 506b, actuators 508a, 508b, and mount force actuation devices 510a, 510b and actuation system 505b can include mounts 506c, 506d, actuators 508c, 508d, and mount force actuation devices 510c, 5 lOd. A person skilled in the art would recognize that each of actuation systems 505 can include any number of mounts 506, actuators 508, and mount force actuation devices 510.

[0073] In some aspects, enumerative adjectives (e.g., “first,” “second,” “third,” or the like) can be used to distinguishing like elements without establishing an order, hierarchy, quantity, or permanent numeric assignment. For example, the terms “first support structure” and “second support structure” can be used in a manner analogous to “ith support structure” and “j th support structure” so as to facilitate the distinguishing of two support structures without specifying a particular order, hierarchy, quantity, or immutable numeric correspondence, unless otherwise noted.

[0074] In some aspects, the plurality of mounts 506 can be static support structures coupled to chuck 502. The plurality of mounts 506 can be configured to support a plurality of actuators 508 and / or a plurality of mount force actuation devices 510.

[0075] In the example aspect shown in FIG. 5, object force application system 504 can include first, second, third, and fourth mounts 506a-506d. A person skilled in the art would recognize that any number of mounts 506 can be coupled to chuck 502 such as, for example, two mounts 506 or six mounts 506.

[0076] In some aspects, the plurality of actuators 508 can be coupled to corresponding ones of the plurality of mounts 506. In some aspects, multiple ones of the plurality of actuators 508 can be coupled to one of the plurality of mounts 506. In some aspects, the plurality of actuators 508 can be configured to perform translational movement in a horizontal XY-plane based on a signal received from control system 516. For example, the plurality of actuators 508 can be configured to laterally move toward or away from side edges of an object 518.

[0077] In the example aspect shown in FIG. 5, object force application system 504 can include first, second, third, and fourth actuators 508a-508d coupled to corresponding ones of the first, second, third, and fourth mounts 506a-506d. A person skilled in the art would recognize that any number of actuators 508 canbe used within object force application system 504 such as, for example, two actuators 508 or six actuators 508.

[0078] In some aspects, the plurality of mount force actuation devices 510 can be coupled to corresponding ones of the plurality of mounts 506. In some aspects, multiple ones of the plurality of mount force actuation devices 510 can be coupled to one of the plurality of mounts 506. In some aspects, the plurality of mount force actuation devices 510 can be voltage-controlled electrodes. In some aspects, the plurality of mount force actuation devices 510 can be voltage -controlled, flux-controlled, or current-controlled electromagnets.

[0079] In the example aspect shown in FIG. 5, object force application system 504 can include first, second, third, and fourth mount force actuation devices 510a-510d coupled to corresponding ones of the first, second, third, and fourth mounts 506a-506d. In the example aspect shown in FIG. 5, first, second, third, and fourth mount force actuation devices 510a-510d can include at least one of voltage-controlled electrodes or voltage-controlled, flux-controlled, or current-controlled electromagnets. A person skilled in the art would recognize that any number of mount force actuation devices 510 can be used within object force application system 504 such as, for example, two mount force actuation devices 510 or six mount force actuation devices 510.

[0080] In some aspects, object 518 can be a reticle. In this example embodiment, object 518 can be supported by system 500 implemented within support structure MT or reticle stage 200. In some aspects, object 518 can be a wafer (e.g., a substrate). In this example embodiment, object 518 can be supported by system 500 implemented within substrate table WT (e.g., a wafer table). In some aspects, object 518 can be a mirror block. In this example embodiment, object 518 can be supported by system 500 implemented within substrate table WT (e.g., a wafer table).

[0081] In some aspects, the plurality of object force actuation devices 512 can be disposed on first and second opposite edges 520a, 520b of object 518. In some aspects, the ones of the plurality of object force actuation devices 512 disposed on first edge 520a can be located adjacent to the ones of the plurality of mount force actuation devices 510 located near first edge 520a, and the ones of the plurality of object force actuation devices 512 disposed on second edge 520b can be located adjacent to the ones of the plurality of mount force actuation devices 510 located near second edge 520b. In this configuration, each one of the plurality of object force actuation devices 512 can form a gap (collectively, gaps 522) with respect to corresponding adjacent ones of the plurality of mount force actuation devices 510.

[0082] In some aspects, one of the plurality of object force actuation devices 512 can be disposed on first edge 520a and one of the plurality of object force actuation devices 512 can be disposed on second edge 520b. In some aspects, multiple ones of the plurality of object force actuation devices 512 can be disposed on first edge 520a and multiple ones of the plurality of object force actuation devices 512 can be disposedon second edge 520b. In some aspects, the number of object force actuation devices 512 disposed on first edge 520a can be equivalent to the number of mount force actuation devices 510 located near first edge 520a, and the number of object force actuation devices 512 disposed on second edge 520b can be equivalent to the number of mount force actuation devices 510 located near second edge 520b. In some aspects, the number of object force actuation devices 512 disposed on first edge 520a can be fewer than the number of mount force actuation devices 510 located near first edge 520a, and the number of object force actuation devices 512 disposed on second edge 520b can be fewer than the number of mount force actuation devices 510 located near second edge 520b.

[0083] In some aspects, the plurality of object force actuation devices 512 can include an electrically conductive material. In some aspects, the plurality of object force actuation devices 512 can include a magnetic material. In some aspects, the plurality of object force actuation devices 512 each can be a coating applied on object 518. In some aspects, the plurality of object force actuation devices 512 each can be a plate adhered to object 518.

[0084] In the example aspect shown in FIG. 5, object force application system 504 can include first and second object force actuation devices 512a, 512b on respective first and second opposite edges 520a, 520b of object 518. In this example configuration, first and second object force actuation devices 512a, 512b can be located adjacent to and forming first, second, third, and fourth gaps 522a-522d with respect to the first, second, third, and fourth mount force actuation devices 510a-510d. In this example configuration, the number of object force actuation devices 512 disposed on first edge 520a is fewer than the number of mount force actuation devices 510 located near first edge 520a, and the number of object force actuation devices 512 disposed on second edge 520b is fewer than the number of mount force actuation devices 510 located near second edge 520b. In the example aspect shown in FIG. 5, first and second object force actuation devices 512a, 512b can include at least one of an electrically conductive material or a magnetic material. In the example aspect shown in FIG. 5, first and second object force actuation devices 512a, 512b can include at least one of a coating applied on object 518 or a plate adhered to object 518. A person skilled in the art would recognize that any number of object force actuation devices 512 can be used within object force application system 504 such as, for example, four object force actuation devices 512 or six object force actuation devices 512.

[0085] In some aspects, each of the plurality of mount force actuation devices 510 can be configured to produce at least one force (collectively, forces 524) on at least one of the plurality of object force actuation devices 512. In some aspects, forces 524 can be attractive forces configured to pull at least one of the plurality of object force actuation devices 512 toward corresponding ones of the plurality of mount force actuation devices 510. In some aspects, forces 524 can be electrostatic forces. In some aspects, forces 524 can be electromagnetic forces.

[0086] In the example aspect shown in FIG. 5, first and second forces 524a, 524b can be produced between first and second mount force actuation devices 510a, 510b and the first object force actuation device 512a. In the example aspect shown in FIG. 5, third and fourth forces 524c, 524d produced between the third and fourth mount force actuation devices 510c, 5 lOd and the second object force actuation device 512b. In the example aspect shown in FIG. 5, first and second forces 524a, 524b can be first and second attractive forces configured to pull the first object force actuation device 512a toward the respective first and second mount force actuation devices 510a, 510b. In this configuration, first and second forces 524a, 524b can pull object 518 in first direction 526 while chuck 502 is moving in first direction 526. In the example aspect shown in FIG. 5, third and fourth forces 524c, 524d comprise third and fourth attractive forces configured to pull the second object force actuation device 512b toward the respective third and fourth mount force actuation devices 510c, 5 lOd. In this configuration, third and fourth forces 524c, 524d can pull object 518 in second direction 528 while chuck 502 is moving in second direction 528. A person skilled in the art would recognize that the number of forces 524 can vary based on the number of mount force actuation devices 510 used within object force application system 504.

[0087] In some aspects, measuring system 514 can be configured to measure the length of gaps 522. In the example aspect shown in FIG. 5, object force application system 504 can include measuring system 514 configured to measure the first, second, third, and fourth gaps 522a-522d. Measuring system 514 can include any type of measurement device used for measuring distance (e.g., an interferometer). A person skilled in the art would recognize that measuring system 514 can measure any number of gaps 522, in which the number of gaps 522 depends on the number of mount force actuation devices 510 and the number of object force actuation devices 512 used within object force application system 504.

[0088] In some aspects, based on the measuring performed by measuring system 514, control system 516 can be configured to adjust forces 524 produced between ones of the plurality of mount force actuation devices 510 and corresponding ones of the plurality of object force actuation devices 512. Control system 516 can adjust forces 524 by moving individual ones of actuators 508 and / or adjusting a voltage or a current provided to individual ones of the plurality of mount force actuation devices 510. In some aspects, control system 516 can include an electrical control subsystem and a position control subsystem. The electrical control subsystem of control system 516 can adjust a voltage or a current supplied to each of mount force actuation devices 510 to adjust forces 524 such that the length of gaps 522 are maintained within a predetermined tolerance. The position control subsystem of control system 516 can move individual ones of the plurality of actuators 508 to adjust forces 524 such that the length of gaps 522 are maintained within a predetermined tolerance. The predetermined tolerance of gaps 522 may dynamically change based on the desired operation of the object force application system 504. In some aspects, control system 516 can selectively adjust a voltage or a current provided to mount force actuation devices 510 to apply at least oneforce 524 on a portion of at least one of the plurality of object force actuation devices 512 such that object 518 rotates. In some aspects, control system 516 can selectively move individual ones of the plurality of actuators 508 to apply at least one force 524 on a portion of at least one of the plurality of object force actuation devices 512 such that object 518 rotates.

[0089] In the example aspect shown in FIG. 5, object force application system 504 can include control system 516 configured to adjust a voltage or a current supplied to first through fourth mount force actuation devices 510a-510d and / or to move the first through fourth actuators 508a-508d to adjust first and second forces 524a, 524b produced between first and second mount force actuation devices 510a, 510b and the first object force actuation device 512a and third and fourth forces 524c, 524d produced between the third and fourth mount force actuation devices 510c, 510d and the second object force actuation device 512b based on the measuring, such that the first, second, third, and fourth gaps 522a-522d are maintained within a predetermined tolerance. In the example aspect shown in FIG. 5, control system 516 can be configured to selectively adjust a voltage or a current provided to the first through fourth mount force actuation devices 510a-510d to apply at least one of the first, second, third, and fourth forces 524a-524d on a portion of at least one of the first and second object force actuation devices 512a, 512b such that the object 518 rotates. In the example aspect shown in FIG. 5, control system 516 can be configured to selectively move the first, second, third, and fourth actuators 508a-508d to apply at least one of the first, second, third, and fourth forces 524a-524d on a portion of at least one of the first and second object force actuation devices 512a, 512b such that object 518 rotates.

[0090] FIG. 6 shows a method 600 for operating an object force application system, according to some aspects. In some aspects, the object force application system can be object force application system 504 described with regard to FIG. 5.

[0091] In some aspects, at step S602, an object (e.g., object 518) can be set on a chuck (e.g., chuck 502). In some aspects, the object can be a reticle, a wafer, or a mirror block.

[0092] In some aspects, at step S604, first through fourth actuators (e.g., actuators 508a-508d), coupled to corresponding first through fourth mounts (e.g., mounts 506a-506d), can move first through fourth mount force actuation devices (e.g., mount force actuation devices 510a-510d) laterally inward toward first and second object force actuation devices (e.g., object force actuation devices 512a, 512b) on respective first and second opposite edges (e.g., edges 520a, 520b) of the object.

[0093] In some aspects, at step S606, first through fourth gaps (e.g., gaps 522a-522d) can be formed by positioning first and second mount force actuation devices adjacent to and away from first object force actuation device within a predetermined tolerance and third and fourth mount force actuation devices adjacent to and away from second object force actuation device within the predetermined tolerance.

[0094] In some aspects, at step S608, the chuck can be moved with a high acceleration.

[0095] In some aspects, at step S610, first through fourth gaps can be measured by a measuring system (e.g., measuring system 514).

[0096] In some aspects, at step S612, a control system (e.g., control system 516) can adjust a voltage or a current supplied to each of the mount force actuation devices and / or move the first through fourth actuators to adjust first and second forces (e.g., forces 524a, 524b) produced between first and second mount force actuation devices and the first object force actuation device and third and fourth forces (e.g., forces 524c, 524d) produced between the third and fourth mount force actuation devices and the second object force actuation device based on the measuring, such that the first, second, third, and fourth gaps are maintained within the predetermined tolerance. In some aspects, the control system can be configured to selectively adjust a voltage or a current provided to the first through fourth mount force actuation devices to apply at least one of the first, second, third, and fourth forces on a portion of at least one of the first and second object force actuation devices such that the object rotates. In some aspects, the control system can be configured to selectively move the first, second, third, and fourth actuators to apply at least one of the first, second, third, and fourth forces on a portion of at least one of the first and second object force actuation devices such that the object rotates.

[0097] The method steps of FIG. 6 can be performed in any conceivable order and it is not required that all steps be performed. Moreover, the method steps of FIG. 6 described above merely reflect an example of steps and are not limiting. That is, further method steps and functions are envisaged based on aspects described in reference to FIGS. 1-5.

[0098] Example Electrostatic Object Force Application System

[0099] FIGS. 7A and 7B show an electrostatic object force application system 704 as part of a system 700, according to some aspects. The above discussion of system 500 shown in FIG. 5 applies to system 700 shown in FIGS. 7A and 7B. The aspects of system 500 shown in FIG. 5, for example, and the aspects of system 700 shown in FIGS. 7A and 7B may be similar. Similar reference numbers are used to indicate features of the aspects of system 500 shown in FIG. 5 and the similar features of the aspects of system 700 shown in FIGS. 7A and 7B.

[0100] FIG. 7A shows a perspective view of system 700, according to some aspects. In some aspects, system 700 can include a chuck 702 and an electrostatic object force application system 704 mounted on chuck 702. In some aspects, system 700 can be an aspect of system 500. In some aspects, system 700 can be implemented in lithographic apparatus 100 and / or lithographic apparatus 100’. For example, system 700 can be implemented within support structure MT in lithographic apparatus 100 and / or lithographic apparatus 100’. In another example, system 700 can be implemented within reticle stage 200 in lithographic apparatus 100 and / or lithographic apparatus 100’. In another example, system 700 can be implemented within substrate table WT in lithographic apparatus 100 and / or lithographic apparatus 100’.

[0101] In some aspects, chuck 702 can be an actuated structure (e.g., for coarse motion of an object 718). The motion of chuck 702 can be limited to an axis (e.g., Y-axis) using guide rails or a contactless method (e.g., magnetic levitation) (guide devices not shown). In one example, chuck 702 can move in a first direction 726 along the Y-axis and in a second direction 728 opposite to first direction 726 along the Y- axis. The coordinate axes X and Y are provided as an example and are not to be construed as limiting.

[0102] In some aspects, chuck 702 can move at high accelerations. In some aspects, the high acceleration can be, for example, approximately 4-100g, 10-50g, 20-40g, or the like (where g is 9.8 m / s2). A high acceleration can increase lithographic print production (e.g., increase throughput). Lithographic pattern transfer can be performed when chuck 702 is in motion, for example, when it reaches a constant coasting speed. Coasting speeds can be, for example, 0.5-10.0 m / s, 1.0-7.0 m / s, 3.0-5.0 m / s, orthe like. Performing the pattern transfer at a constant scanning speed can result in more accurate transfers of the printed pattern, whereas printing during acceleration can be accompanied by larger positional uncertainties.

[0103] The term “throughput” can be understood as the amount of material or items passing through a system or process. In some aspects, the term “throughput” can be used to characterize a rate of lithographic fabrication. For example, throughput can refer to a rate at which lithographic fabrication is completed on wafers, a rate at which a wafer clears a particular fabrication step and moves to the next step, or the like. Throughput can be a performance marker of a lithographic apparatus. It is desirable for lithographic systems to output as many products as possible in as little time as possible. Lithographic fabrication can comprise several complex processes. Each part of the process can involve tradeoffs that balance quality (e.g., subnanometer accuracy, high yield) and drawbacks (e.g., slower fabrication, cost). For example, to improve pattern-transfer speeds, lithography can implement faster, yet accurate, actuation of substrates and / or masks.

[0104] In some aspects, chuck 702 can use mechanical, vacuum, electrostatic, or other clamping techniques to hold an object 718. Under ideal conditions, mutual friction between object 718 and chuck 702 can ensure that there is no slippage therebetween. However, mechanical stresses due to high accelerations can induce some slippage, resulting in printing error. The errors can be highly detrimental due to the possibility of losing thousands of device products by the time the error can be detected. Therefore, electrostatic object force application system 704 can be used to ensure that object 718 is held at a desired position on chuck 702, for example, with respect to a projection system (e.g., projection system PS described with regard to FIGS. 1A and IB) while the chuck 702 is accelerating.

[0105] In some aspects, electrostatic object force application system 704 can include a plurality of mounts (collectively, mounts 706), a plurality of actuators (collectively, actuators 708), a plurality of mount electrostatic actuation devices (collectively, mount electrostatic actuation devices 710), a plurality of objectelectrostatic actuation devices (collectively, object electrostatic actuation devices 712), a measuring system 714, and a control system 716.

[0106] In some aspects, enumerative adjectives (e.g., “first,” “second,” “third,” or the like) can be used to distinguishing like elements without establishing an order, hierarchy, quantity, or permanent numeric assignment. For example, the terms “first support structure” and “second support structure” can be used in a manner analogous to “ith support structure” and “j th support structure” so as to facilitate the distinguishing of two support structures without specifying a particular order, hierarchy, quantity, or immutable numeric correspondence, unless otherwise noted.

[0107] In some aspects, the plurality of mounts 706 can be static support structures coupled to chuck 702. The plurality of mounts 706 can be configured to support a plurality of actuators 708 and / or a plurality of mount electrostatic actuation devices 710.

[0108] In the example aspect shown in FIG. 7A, electrostatic object force application system 704 can include first, second, third, and fourth mounts 706a-706d. A person skilled in the art would recognize that any number of mounts 706 can be coupled to chuck 702 such as, for example, two mounts 706 or six mounts 706.

[0109] In some aspects, the plurality of actuators 708 can be coupled to corresponding ones of the plurality of mounts 706. In some aspects, multiple ones of the plurality of actuators 708 can be coupled to one of the plurality of mounts 706. In some aspects, one or more of the plurality of actuators 708 can be located adjacent to a first side edge 720a of object 718 and another one or more of the plurality of actuators 708 can be located adjacent to a second side edge 720b of object 718. In some aspects, the plurality of actuators 708 can be disposed along a length of chuck 702 with periodically spaced intervals or variably spaced intervals. In the example aspect shown in FIG. 7A, electrostatic object force application system 704 can include first, second, third, and fourth actuators 708a-708d coupled to corresponding ones of the first, second, third, and fourth mounts 706a-706d. A person skilled in the art would recognize that any number of actuators 708 can be used within electrostatic object force application system 704 such as, for example, two actuators 708 or six actuators 708.

[0110] In some aspects, the plurality of actuators 708 can be configured to perform translational movement in a horizontal XY-plane based on a signal received from control system 716. For example, the plurality of actuators 708 can be configured to laterally move toward or away from side edges 720a, 720b of object 718. In some aspects, the plurality of actuators 708 can be configured to move the plurality of mount electrostatic actuation devices 710 laterally toward or away from the plurality of object electrostatic actuation devices 712 on edges 720a, 720b of object 718.[oni] In some aspects, the plurality of actuators 708 each can perform coarse adjustments and / or fine adjustments. In some aspects, the plurality of actuators 708 each can be piezoactuators configured to expandor contract in a horizontal XY-plane based on a signal received from control system 716. In some aspects, the plurality of actuators 708 each can include a combination of a mechanical lead screw for coarse adjustments and a piezoactuator for fine adjustments. In some aspects, the plurality of actuators 708 each can include ferromagnetic materials configured to expand or contract in response to a magnetic field due to magnetostriction.

[0112] In some aspects, the plurality of mount electrostatic actuation devices 710 can be coupled to corresponding ones of the plurality of mounts 706. In some aspects, multiple ones of the plurality of mount electrostatic actuation devices 710 can be coupled to one of the plurality of mounts 706. In some aspects, the plurality of mount electrostatic actuation devices 710 can include voltage-controlled electrodes configured to electrostatically interact with the plurality of object electrostatic actuation devices 712. In this example configuration, a positive voltage can be applied to one of the voltage -controlled electrodes and a negative voltage can be applied to another one of the voltage -controlled electrodes. The applied voltages can exert an electrostatic force on an electrically conductive material coupled to object 718, thereby causing charged particles in the material to move and therefore cause the object 718 to move. In some aspects, the magnitude of the voltage applied to the voltage-controlled electrodes can be up to about a few thousand volts. For example, about 2,000 volts can be applied to the voltage-controlled electrodes.

[0113] In the example aspect shown in FIG. 7A, electrostatic object force application system 704 can include first, second, third, and fourth mount electrostatic actuation devices 710a-710d coupled to corresponding ones of the first, second, third, and fourth mounts 706a-706d. In the example aspect shown in FIG. 7A, first, second, third, and fourth mount electrostatic actuation devices 710a-710d can include voltage-controlled electrodes configured to electrostatically interact with the first and second object electrostatic actuation devices 712a, 712b. A person skilled in the art would recognize that any number of mount electrostatic actuation devices 710 can be used within electrostatic object force application system 704 such as, for example, two mount electrostatic actuation devices 710 or six mount electrostatic actuation devices 710.

[0114] In some aspects, object 718 can be a reticle. In this example embodiment, object 718 can be supported by system 700 implemented within support structure MT or reticle stage 200. In some aspects, object 718 can be a wafer (e.g., a substrate). In this example embodiment, object 718 can be supported by system 700 implemented within substrate table WT (e.g., a wafer table). In some aspects, object 718 can be a mirror block. In this example embodiment, object 718 can be supported by system 700 implemented within substrate table WT (e.g., a wafer table).

[0115] In some aspects, the plurality of object electrostatic actuation devices 712 can be disposed on first and second opposite edges 720a, 720b of object 718. In some aspects, the ones of the plurality of object electrostatic actuation devices 712 disposed on first edge 720a can be located adjacent to the ones of theplurality of mount electrostatic actuation devices 710 located near first edge 720a, and the ones of the plurality of object electrostatic actuation devices 712 disposed on second edge 720b can be located adjacent to the ones of the plurality of mount electrostatic actuation devices 710 located near second edge 720b. In this configuration, each one of the plurality of object electrostatic actuation devices 712 can form a gap (collectively, gaps 722) with respect to corresponding adjacent ones of the plurality of mount electrostatic actuation devices 710.

[0116] In some aspects, one of the plurality of object electrostatic actuation devices 712 can be disposed on first edge 720a and one of the plurality of object electrostatic actuation devices 712 can be disposed on second edge 720b. In some aspects, multiple ones of the plurality of object electrostatic actuation devices 712 can be disposed on first edge 720a and multiple ones of the plurality of object electrostatic actuation devices 712 can be disposed on second edge 720b. In some aspects, the number of object electrostatic actuation devices 712 disposed on first edge 720a can be equivalent to the number of mount electrostatic actuation devices 710 located near first edge 720a, and the number of object electrostatic actuation devices 712 disposed on second edge 720b can be equivalent to the number of mount electrostatic actuation devices 710 located near second edge 720b. In some aspects, the number of object electrostatic actuation devices 712 disposed on first edge 720a can be fewer than the number of mount electrostatic actuation devices 710 located near first edge 720a, and the number of object electrostatic actuation devices 712 disposed on second edge 720b can be fewer than the number of mount electrostatic actuation devices 710 located near second edge 720b.

[0117] In some aspects, the plurality of object electrostatic actuation devices 712 each can include an electrically conductive material. In some aspects, the plurality of object electrostatic actuation devices 712 each can be a coating applied on object 718. In some aspects, the plurality of object electrostatic actuation devices 712 each can include a plate adhered to object 718.

[0118] In the example aspect shown in FIG. 7A, electrostatic object force application system 704 can include first and second object electrostatic actuation devices 712a, 712b on respective first and second opposite edges 720a, 720b of object 718. In this example configuration, first and second object electrostatic actuation devices 712a, 712b can be located adjacent to and forming first, second, third, and fourth gaps 722a-722d with respect to the first, second, third, and fourth mount electrostatic actuation devices 710a- 710d. In the example aspect shown in FIG. 7A, first and second object electrostatic actuation devices 712a, 712b each can include an electrically conductive material. In the example aspect shown in FIG. 7A, first and second object electrostatic actuation devices 712a, 712b can include first and second coatings applied on the respective first and second opposite edges 720a, 720b of object 718. A person skilled in the art would recognize that any number of object electrostatic actuation devices 712 can be used within electrostaticobject force application system 704 such as, for example, four object electrostatic actuation devices 712 or six object electrostatic actuation devices 712.

[0119] In some aspects, each of the plurality of mount electrostatic actuation devices 710 can be configured to produce at least one force (collectively, forces 724) on at least one of the plurality of object electrostatic actuation devices 712. In some aspects, forces 724 can be attractive forces configured to pull at least one of the plurality of object electrostatic actuation devices 712 toward corresponding ones of the plurality of mount electrostatic actuation devices 710. In some aspects, each of forces 724 can be electrostatic forces with a magnitude dependent on the length of the corresponding ones of gaps 722.

[0120] In the example aspect shown in FIG. 7A, first and second forces 724a, 724b can be produced between first and second mount electrostatic actuation devices 710a, 710b and the first object electrostatic actuation device 712a. In the example aspect shown in FIG. 7A, third and fourth forces 724c, 724d produced between the third and fourth mount electrostatic actuation devices 710c, 710d and the second object electrostatic actuation device 712b. In the example aspect shown in FIG. 7A, first and second forces 724a, 724b can be first and second attractive forces configured to pull the first object electrostatic actuation device 712a toward the respective first and second mount electrostatic actuation devices 710a, 710b. In this configuration, first and second forces 724a, 724b can pull object 718 in first direction 726 while chuck 702 is moving in first direction 726. In the example aspect shown in FIG. 7A, third and fourth forces 724c, 724d comprise third and fourth attractive forces configured to pull the second object electrostatic actuation device 712b toward the respective third and fourth mount electrostatic actuation devices 710c, 710d. In this configuration, third and fourth forces 724c, 724d can pull object 718 in second direction 728 while chuck 702 is moving in second direction 728. A person skilled in the art would recognize that the number of forces 724 can vary based on the number of mount electrostatic actuation devices 710 used within electrostatic object force application system 704.

[0121] In some aspects, measuring system 714 can be configured to measure the length of gaps 722. Measuring system 714 can include any type of measurement device used for measuring distance (e.g., a capacitance gauge, an interferometer, etc.). In some aspects, measuring system 714 can include a capacitance gauge configured to apply a varying voltage to mount electrostatic actuation devices 710 to measure a capacitance of corresponding gaps 722. Because capacitance is inversely proportional to distance between electrically conductive plates, capacitance can be used to determine the distance of gaps 722 between mount electrostatic actuation devices 710 and corresponding object electrostatic actuation devices 712. In some aspects, a standing voltage with a sinusoidal oscillation can be applied to mount electrostatic actuation devices 710 to provide relatively constant forces 724 and a sufficient amount of current flowing to measure gaps 722 accurately with measuring system 714.

[0122] In the example aspect shown in FIG. 7A, electrostatic object force application system 704 can include measuring system 714 configured to measure the first, second, third, and fourth gaps 722a-722d. In the example aspect shown in FIG. 7A, measuring system 714 can include a capacitance gauge configured to apply a varying voltage to the first, second, third, and fourth mount electrostatic actuation devices 710a- 7I0d to measure a capacitance of the first, second, third, and fourth gaps 722a-722d. A person skilled in the art would recognize that measuring system 714 can measure any number of gaps 722, in which the number of gaps 722 depends on the number of mount electrostatic actuation devices 710 and the number of object electrostatic actuation devices 712 used within electrostatic object force application system 704.

[0123] In some aspects, based on the measuring performed by measuring system 714, control system 716 can be configured to adjust forces 724 produced between ones of the plurality of mount electrostatic actuation devices 710 and corresponding ones of the plurality of object electrostatic actuation devices 712. Control system 716 can adjust forces 724 by moving individual ones of actuators 708 and / or adjusting a voltage or a current provided to individual ones of the plurality of mount electrostatic actuation devices 710. In some aspects, control system 716 can include an electrical control subsystem and a position control subsystem . The electrical control subsystem of control system 716 can adjust a voltage or a current supplied to each of mount electrostatic actuation devices 710 to adjust forces 724 such that the length of gaps 722 are maintained within a predetermined tolerance. The position control subsystem of control system 716 can move individual ones of the plurality of actuators 708 to adjust forces 724 such that the length of gaps 722 are maintained within a predetermined tolerance. The predetermined tolerance of gaps 722 may dynamically change based on the desired operation of the electrostatic object force application system 704.

[0124] In some aspects, control system 716 can selectively adjust a voltage or a current provided to mount electrostatic actuation devices 710 to apply at least one force 724 on a portion of at least one of the plurality of object force actuation devices 712 such that object 718 rotates. In some aspects, control system 716 can selectively move individual ones of the plurality of actuators 708 to apply at least one force 724 on a portion of at least one of the plurality of object electrostatic actuation devices 712 such that object 718 rotates. By adjusting a voltage or a current provided to mount electrostatic actuation devices 710 or moving individual ones of the plurality of actuators 708, control system 716 can maintain spatial control of forces 724. For example, control system 716 can adjust certain forces 724 such that comer portions of object 718 experience a plurality of forces 724 with a greater magnitude than a magnitude of one force 724 applied to a middle portion of object 718.

[0125] In the example aspect shown in FIG. 7A, electrostatic object force application system 704 can include control system 716 configured to adjust a voltage or a current supplied to first through fourth mount electrostatic actuation devices 710a-710d and / or to move the first through fourth actuators 708a-708d to adjust first and second forces 724a, 724b produced between first and second mount electrostatic actuationdevices 710a, 710b and the first object electrostatic actuation device 712a and third and fourth forces 724c, 724d produced between the third and fourth mount electrostatic actuation devices 710c, 710d and the second object electrostatic actuation device 712b based on the measuring, such that the first, second, third, and fourth gaps 722a-722d are maintained within a predetermined tolerance. In the example aspect shown in FIG. 7, control system 716 can be configured to selectively adjust a voltage or a current provided to the first through fourth mount electrostatic actuation devices 71 Oa-71 Od to apply at least one of the first, second, third, and fourth forces 724a-724d on a portion of at least one of the first and second object electrostatic actuation devices 712a, 712b such that the object 718 rotates. In the example aspect shown in FIG. 7A, control system 716 can be configured to selectively move the first, second, third, and fourth actuators 708a- 708d to apply at least one of the first, second, third, and fourth forces 724a-724d on a portion of at least one of the first and second object electrostatic actuation devices 712a, 712b such that object 718 rotates.

[0126] FIG. 7B shows a side view of system 700, according to some aspects. FIG. 7B can comprise a different view of system 700 shown in FIG. 7A for illustrating additional details. For clarity purposes, new elements may be shown while some may be hidden or unlabeled. Therefore, unless otherwise noted, descriptions of elements of FIG. 7A can also apply to FIG. 7B. Elements appearing in FIG. 7A that correspond to elements in FIG. 7B can have the same reference numbers.

[0127] In some aspects, upon operation, chuck 702 can include a clamp 729 configured to hold object 718. In some aspects, the plurality of actuators 708 each can contract to provide clearance for object 718 to be loaded onto clamp 729 on chuck 702. For example, each of the plurality of actuators 708 can be contracted to provide clearance of a few hundred microns on each side of object 718. In one example, the clearance can be about 200 microns. Then, in some aspects, the plurality of actuators 708 each can expand to move the plurality of mount electrostatic actuation devices 710 inwardly toward object electrostatic actuation devices 712 to form gaps 722 from about 10 microns to about 100 microns. For example, gaps 722 can be about 20 microns, about 25 microns, or about 30 microns. Coarse adjustment and fine adjustment by the plurality of actuators 708 can tune the positions of mount electrostatic actuation devices 710 to the positioning of the loaded object 718.

[0128] In some aspects, when chuck 702 begins accelerating, control system 716 can apply a voltage to mount electrostatic actuation devices 710 to produce forces 724 on object electrostatic actuation devices 712. In some aspects, force 724 can be of a magnitude of about 10% to about 50% of a force that accelerates object 718. In some aspects, forces 724 can be attractive forces that pull object electrostatic actuation devices 712 toward the corresponding at least one of the corresponding mount electrostatic actuation devices 710 to keep object 718 stationary relative to chuck 702 while chuck 702 is accelerating, thereby preventing or correcting object slip. The magnitude of forces 724 can depend on the size of corresponding gaps 722, in which a smaller gap 722 provides a greater force 724 because force 724 scales according tothe reciprocal of the square of gap 722. However, contact between mount electrostatic actuation devices 710 and object electrostatic actuation devices 712 can produce a short circuit or cause damage or contamination to object 718. As result, the plurality of actuators 708 can actively adjust their respective positions in real time to maintain gaps 722 within a predetermined tolerance during the accelerations, based on measurements performed by measuring system 714.

[0129] In some aspects, measuring system 714 can measure a relative positioning (e.g., gaps 722) between mount electrostatic actuation devices 710 and corresponding ones of object electrostatic actuation devices 712. For example, measuring system 714 can measure the capacitance of gaps 722 to determine the length of gaps 722. In some aspects, based on the measuring, control system 716 can adjust forces 724 by adjusting the length of gaps 722 by moving corresponding ones of actuators 708, adjusting voltage or current provided to mount electrostatic actuation devices 710, or a combination. The feedback loop of measuring gaps 722 and adjusting actuators 708 can provide tight control over a consistent magnitude of forces 724 without creating a contamination risk based on contact between components. Additionally, electrostatic object force application system 704 can remove some force load off the clamp 729 holding object 718 on chuck 702, thereby further reducing the chance of object slip.

[0130] FIG. 8 shows a method 800 for operating an electrostatic object force application system, according to some aspects. In some aspects, the electrostatic object force application system can be electrostatic object force application system 704 described with regard to FIGS. 7A and 7B.

[0131] In some aspects, at step S802, an object (e.g., object 718) can be set on a chuck (e.g., chuck 702). In some aspects, the object can be a reticle, a wafer, or a mirror block.

[0132] In some aspects, at step S804, first through fourth actuators (e.g., actuators 708a-708d), coupled to corresponding first through fourth mounts (e.g., mounts 706a-706d), can move first through fourth mount electrostatic actuation devices (e.g., mount electrostatic actuation devices 710a-710d) laterally inward toward first and second object electrostatic actuation devices (e.g., object electrostatic actuation devices 712a, 712b) on respective first and second opposite edges (e.g., edges 720a, 720b) of the object.

[0133] In some aspects, at step S806, first through fourth gaps (e.g., gaps 722a-722d) can be formed by positioning first and second mount electrostatic actuation devices adjacent to and away from first object electrostatic actuation device within a predetermined tolerance and third and fourth mount electrostatic actuation devices adjacent to and away from second object electrostatic actuation device within the predetermined tolerance.

[0134] In some aspects, at step S808, the chuck can be moved with a high acceleration.

[0135] In some aspects, at step S810, first through fourth gaps can be measured by a measuring system (e.g., measuring system 714).

[0136] In some aspects, at step S812, a control system (e.g., control system 716) can adjust a voltage or a current supplied to each of the mount electrostatic actuation devices and / or move the first through fourth actuators to adjust first and second forces (e.g., forces 724a, 724b) produced between first and second mount electrostatic actuation devices and the first object electrostatic actuation device and third and fourth forces (e.g., forces 724c, 724d) produced between the third and fourth mount electrostatic actuation devices and the second object electrostatic actuation device based on the measuring, such that the first, second, third, and fourth gaps are maintained within the predetermined tolerance. In some aspects, the control system can be configured to selectively adjust a voltage or a current provided to the first through fourth mount electrostatic actuation devices to apply at least one of the first, second, third, and fourth forces on a portion of at least one of the first and second object electrostatic actuation devices such that the object rotates. In some aspects, the control system can be configured to selectively move the first, second, third, and fourth actuators to apply at least one of the first, second, third, and fourth forces on a portion of at least one of the first and second object electrostatic actuation devices such that the object rotates.

[0137] The method steps of FIG. 8 can be performed in any conceivable order and it is not required that all steps be performed. Moreover, the method steps of FIG. 8 described above merely reflect an example of steps and are not limiting. That is, further method steps and functions are envisaged based on aspects described in reference to FIGS. 1-7B.

[0138] Example Electromagnetic Object Force Application System

[0139] FIGS. 9A and 9B show an electromagnetic object force application system 904 as part of a system 900, according to some aspects. The above discussion of system 500 shown in FIG. 5 applies to system 900 shown in FIGS. 9A and 9B. The aspects of system 500 shown in FIG. 5, for example, and the aspects of system 900 shown in FIGS. 9A and 9B may be similar. Similar reference numbers are used to indicate features of the aspects of system 500 shown in FIG. 5 and the similar features of the aspects of system 900 shown in FIGS. 9A and 9B.

[0140] FIG. 9A shows system 900, according to some aspects. In some aspects, system 900 can include a chuck 902 and an electromagnetic object force application system 904 mounted on chuck 902. In some aspects, system 900 can be an aspect of system 500. In some aspects, system 900 can be implemented in lithographic apparatus 100 and / or lithographic apparatus 100’. For example, system 900 can be implemented within support structure MT in lithographic apparatus 100 and / or lithographic apparatus 100’. In another example, system 900 can be implemented within reticle stage 200 in lithographic apparatus 100 and / or lithographic apparatus 100’. In another example, system 900 can be implemented within substrate table WT in lithographic apparatus 100 and / or lithographic apparatus 100’.

[0141] In some aspects, chuck 902 can be an actuated structure (e.g., for coarse motion of an object 918). The motion of chuck 902 can be limited to an axis (e.g., Y-axis) using guide rails or a contactless method(e.g., magnetic levitation) (guide devices not shown). In one example, chuck 902 can move in a first direction 926 along the Y-axis and in a second direction 928 opposite to first direction 926 along the Y- axis. The coordinate axes X and Y are provided as an example and are not to be construed as limiting.

[0142] In some aspects, chuck 902 can move at high accelerations. In some aspects, the high acceleration can be, for example, approximately 4-100g, 10-50g, 20-40g, or the like (where g is 9.8 m / s2). A high acceleration can increase lithographic print production (e.g., increase throughput). Lithographic pattern transfer can be performed when chuck 902 is in motion, for example, when it reaches a constant coasting speed. Coasting speeds can be, for example, 0.5-10.0 m / s, 1.0-7.0 m / s, 3.0-5.0 m / s, orthe like. Performing the pattern transfer at a constant scanning speed can result in more accurate transfers of the printed pattern, whereas printing during acceleration can be accompanied by larger positional uncertainties.

[0143] The term “throughput” can be understood as the amount of material or items passing through a system or process. In some aspects, the term “throughput” can be used to characterize a rate of lithographic fabrication. For example, throughput can refer to a rate at which lithographic fabrication is completed on wafers, a rate at which a wafer clears a particular fabrication step and moves to the next step, or the like. Throughput can be a performance marker of a lithographic apparatus. It is desirable for lithographic systems to output as many products as possible in as little time as possible. Lithographic fabrication can comprise several complex processes. Each part of the process can involve tradeoffs that balance quality (e.g., subnanometer accuracy, high yield) and drawbacks (e.g., slower fabrication, cost). For example, to improve pattern-transfer speeds, lithography can implement faster, yet accurate, actuation of substrates and / or masks.

[0144] In some aspects, chuck 902 can use mechanical, vacuum, electrostatic, or other clamping techniques to hold an object 918. Under ideal conditions, mutual friction between object 918 and chuck 902 can ensure that there is no slippage therebetween. However, mechanical stresses due to high accelerations can induce some slippage, resulting in printing error. The errors can be highly detrimental due to the possibility of losing thousands of device products by the time the error can be detected. Therefore, electromagnetic object force application system 904 can be used to ensure that object 918 is held at a desired position on chuck 902, for example, with respect to a projection system (e.g., projection system PS described with regard to FIGS. 1A and IB) while chuck 902 is accelerating.

[0145] In some aspects, electromagnetic object force application system 904 can include a plurality of mounts (collectively, mounts 906), a plurality of actuators (collectively, actuators 908), a plurality of mount electromagnetic actuation devices (collectively, mount electromagnetic actuation devices 910), a plurality of object electromagnetic actuation devices (collectively, object electromagnetic actuation devices 912), a measuring system 914, and a control system 916.

[0146] In some aspects, enumerative adjectives (e.g., “first,” “second,” “third,” or the like) can be used to distinguishing like elements without establishing an order, hierarchy, quantity, or permanent numeric assignment. For example, the terms “first support structure” and “second support structure” can be used in a manner analogous to “ith support structure” and “j th support structure” so as to facilitate the distinguishing of two support structures without specifying a particular order, hierarchy, quantity, or immutable numeric correspondence, unless otherwise noted.

[0147] In some aspects, the plurality of mounts 906 can be static support structures coupled to chuck 902. The plurality of mounts 906 can be configured to support a plurality of actuators 908 and / or a plurality of mount electromagnetic actuation devices 910.

[0148] In the example aspect shown in FIG. 9A, electromagnetic object force application system 904 can include first, second, third, and fourth mounts 906a-906d. A person skilled in the art would recognize that any number of mounts 906 can be coupled to chuck 902 such as, for example, two mounts 906 or six mounts 906.

[0149] In some aspects, the plurality of actuators 908 can be coupled to corresponding ones of the plurality of mounts 906. In some aspects, multiple ones of the plurality of actuators 908 can be coupled to one of the plurality of mounts 906. In some aspects, one or more of the plurality of actuators 908 can be located adjacent to a first side edge 920a of object 918 and another one or more of the plurality of actuators 908 can be located adjacent to a second side edge 920b of object 918. In some aspects, the plurality of actuators 908 can be disposed along a length of chuck 902 with periodically spaced intervals or variably spaced intervals. In the example aspect shown in FIG. 9A, electromagnetic object force application system 904 can include first, second, third, and fourth actuators 908a-908d coupled to corresponding ones of the first, second, third, and fourth mounts 906a-906d. A person skilled in the art would recognize that any number of actuators 908 can be used within electromagnetic object force application system 904 such as, for example, two actuators 908 or six actuators 908.

[0150] In some aspects, the plurality of actuators 908 can be configured to perform translational movement in a horizontal XY-plane based on a signal received from control system 916. For example, the plurality of actuators 908 can be configured to laterally move toward or away from side edges 920a, 920b of object 918. In some aspects, the plurality of actuators 908 can be configured to move the plurality of mount electromagnetic actuation devices 910 laterally toward or away from the plurality of obj ect electromagnetic actuation devices 912 on edges 920a, 920b of object 918.

[0151] In some aspects, the plurality of actuators 908 each can perform coarse adjustments and / or fine adjustments. In some aspects, the plurality of actuators 908 each can be piezoactuators configured to expand or contract in a horizontal XY-plane based on a signal received from control system 916. In some aspects, the plurality of actuators 908 each can include a combination of a mechanical lead screw for coarseadjustments and a piezoactuator for fine adjustments. In some aspects, the plurality of actuators 908 each can include ferromagnetic materials configured to expand or contract in response to a magnetic field due to magnetostriction.

[0152] In some aspects, electromagnetic object force application system 904 may not include the plurality of actuators 908. In this example configuration, mount electromagnetic actuation devices 910 can be coupled to corresponding ones of the plurality of mounts 906 and can be configured to remain in a static position as part of mounts 906.

[0153] In some aspects, the plurality of mount electromagnetic actuation devices 910 can be coupled to corresponding ones of the plurality of mounts 906. In some aspects, multiple ones of the plurality of mount electromagnetic actuation devices 910 can be coupled to one ofthe plurality of mounts 906. In some aspects, the plurality of mount electromagnetic actuation devices 910 can include voltage-controlled, flux- controlled, or current-controlled electromagnets configured to magnetically interact with the plurality of object electromagnetic actuation devices 912. For example, the plurality of mount electromagnetic actuation devices 910 can include coils of wire wrapped around a metal core (e.g., a ferrite core) configured to generate and adjust magnetic fields.

[0154] In the example aspect shown in FIG. 9A, electromagnetic object force application system 904 can include first, second, third, and fourth mount electromagnetic actuation devices 910a-910d coupled to corresponding ones of the first, second, third, and fourth mounts 906a-906d. In the example aspect shown in FIG. 9A, first, second, third, and fourth mount electromagnetic actuation devices 910a-910d can include voltage-controlled, flux-controlled, or current-controlled electromagnets configured to magnetically interact with the first and second object electromagnetic actuation devices 912a, 912b. A person skilled in the art would recognize that any number of mount electromagnetic actuation devices 910 can be used within electromagnetic object force application system 904 such as, for example, two mount electromagnetic actuation devices 910 or six mount electromagnetic actuation devices 910.

[0155] In some aspects, object 918 can be a reticle. In this example embodiment, object 918 can be supported by system 900 implemented within support structure MT or reticle stage 200. In some aspects, object 918 can be a wafer (e.g., a substrate). In this example embodiment, object 918 can be supported by system 900 implemented within substrate table WT (e.g., a wafer table). In some aspects, object 918 can be a mirror block. In this example embodiment, object 918 can be supported by system 900 implemented within substrate table WT (e.g., a wafer table).

[0156] In some aspects, the plurality of object electromagnetic actuation devices 912 can be disposed on first and second opposite edges 920a, 920b of object 918. In some aspects, the ones ofthe plurality of object electromagnetic actuation devices 912 disposed on first edge 920a can be located adjacent to the ones of the plurality of mount electromagnetic actuation devices 910 located near first edge 920a, and the ones ofthe plurality of object electromagnetic actuation devices 912 disposed on second edge 920b can be located adjacent to the ones of the plurality of mount electromagnetic actuation devices 910 located near second edge 920b. In this configuration, each one of the plurality of object electromagnetic actuation devices 912 can form a gap (collectively, gaps 922) with respect to corresponding adjacent ones of the plurality of mount electromagnetic actuation devices 910.

[0157] In some aspects, one of the plurality of object electromagnetic actuation devices 912 can be disposed on first edge 920a and one of the plurality of object electromagnetic actuation devices 912 can be disposed on second edge 920b. In some aspects, multiple ones of the plurality of object electromagnetic actuation devices 912 can be disposed on first edge 920a and multiple ones of the plurality of object electromagnetic actuation devices 912 can be disposed on second edge 920b. In some aspects, the number of obj ect electromagnetic actuation devices 912 disposed on first edge 920a can be equivalent to the number of mount electromagnetic actuation devices 910 located near first edge 920a, and the number of object electromagnetic actuation devices 912 disposed on second edge 920b can be equivalent to the number of mount electromagnetic actuation devices 910 located near second edge 920b. In some aspects, the number of object electromagnetic actuation devices 912 disposed on first edge 920a can be fewer than the number of mount electromagnetic actuation devices 910 located near first edge 920a, and the number of object electromagnetic actuation devices 912 disposed on second edge 920b can be fewer than the number of mount electromagnetic actuation devices 910 located near second edge 920b.

[0158] In some aspects, the plurality of object electromagnetic actuation devices 912 each can include a magnetic material that responds to magnetic fields (e.g., a metal, iron, ferrite, or the like). In some aspects, the plurality of object electromagnetic actuation devices 912 each can include a plate adhered to object 918 with an affixing structure (e.g., epoxy). In some aspects, the plurality of object electromagnetic actuation devices 912 each can be a coating applied on object 918.

[0159] In the example aspect shown in FIG. 9A, electromagnetic object force application system 904 can include first and second object electromagnetic actuation devices 912a, 912b on respective first and second opposite edges 920a, 920b of object 918. In this example configuration, first and second object electromagnetic actuation devices 912a, 912b can be located adjacent to and forming first, second, third, and fourth gaps 922a-922d with respect to the first, second, third, and fourth mount electromagnetic actuation devices 910a-910d. In the example aspect shown in FIG. 9A, first and second object electromagnetic actuation devices 912a, 912b each can include a magnetic material. In the example aspect shown in FIG. 9A, first and second object electromagnetic actuation devices 912a, 912b can include first and second plates adhered to the respective first and second opposite edges 920a, 920b of object 918. A person skilled in the art would recognize that any number of object electromagnetic actuation devices 912can be used within electromagnetic object force application system 904 such as, for example, four object electromagnetic actuation devices 912 or six object electromagnetic actuation devices 912.

[0160] In some aspects, each of the plurality of mount electromagnetic actuation devices 910 can be configured to produce at least one force (collectively, forces 924) on at least one of the plurality of object electromagnetic actuation devices 912. In some aspects, forces 924 can be attractive forces configured to pull at least one of the plurality of object electromagnetic actuation devices 912 toward corresponding ones of the plurality of mount electromagnetic actuation devices 910. In some aspects, forces 924 can be magnetic forces.

[0161] In the example aspect shown in FIG. 9A, first and second forces 924a, 924b can be produced between first and second mount electromagnetic actuation devices 910a, 910b and the first object electromagnetic actuation device 912a. In the example aspect shown in FIG. 9A, third and fourth forces 924c, 924d produced between the third and fourth mount electromagnetic actuation devices 910c, 91 Od and the second object electromagnetic actuation device 912b. In the example aspect shown in FIG. 9A, first and second forces 924a, 924b can be first and second attractive forces configured to pull the first object electromagnetic actuation device 912a toward the respective first and second mount electromagnetic actuation devices 910a, 910b. In this configuration, first and second forces 924a, 924b can pull object 918 in first direction 926 while chuck 902 is moving in first direction 926. In the example aspect shown in FIG. 9A, third and fourth forces 924c, 924d comprise third and fourth attractive forces configured to pull the second object electromagnetic actuation device 912b toward the respective third and fourth mount electromagnetic actuation devices 910c, 910d. In this configuration, third and fourth forces 924c, 924d can pull object 918 in second direction 928 while chuck 902 is moving in second direction 928. A person skilled in the art would recognize that the number of forces 924 can vary based on the number of mount electromagnetic actuation devices 910 used within electromagnetic object force application system 904.

[0162] In some aspects, measuring system 914 can be configured to measure the length of gaps 922. Measuring system 914 can include any type of measurement device used for measuring distance (e.g., an interferometer). In the example aspect shown in FIG. 9A, electromagnetic object force application system 904 can include measuring system 914 configured to measure the first, second, third, and fourth gaps 922a- 922d. A person skilled in the art would recognize that measuring system 914 can measure any number of gaps 922, in which the number of gaps 922 depends on the number of mount electromagnetic actuation devices 910 and the number of object electromagnetic actuation devices 912 used within electromagnetic object force application system 904.

[0163] In some aspects, based on the measuring performed by measuring system 914, control system 916 can be configured to adjust forces 924 produced between ones of the plurality of mount electromagnetic actuation devices 910 and corresponding ones of the plurality of object electromagnetic actuation devices912. Control system 916 can adjust forces 924 by moving individual ones of actuators 908 and / or adjusting a voltage, a flux, or a current provided to individual ones of the plurality of mount electromagnetic actuation devices 910. In some aspects, control system 916 can include an electrical control subsystem and aposition control subsystem. The electrical control subsystem of control system 916 can adjust a voltage, a flux, or a current supplied to each of mount electromagnetic actuation devices 910 to adjust forces 924 such that the length of gaps 922 are maintained within a predetermined tolerance. The position control subsystem of control system 916 can move individual ones of the plurality of actuators 908 to adjust forces 924 such that the length of gaps 922 are maintained within a predetermined tolerance. The predetermined tolerance of gaps 922 may dynamically change based on the desired operation of the electromagnetic object force application system 904.

[0164] In some aspects, control system 916 can selectively adjust a voltage, a flux, or a current provided to mount electromagnetic actuation devices 910 to apply at least one force 924 on a portion of at least one of the plurality of object electromagnetic actuation devices 912 such that object 918 rotates. In some aspects, control system 916 can selectively move individual ones of the plurality of actuators 908 to apply at least one force 924 on a portion of at least one of the plurality of object electromagnetic actuation devices 912 such that object 918 rotates. By adjusting a voltage, a flux, or a current provided to mount electromagnetic actuation devices 910 or moving individual ones of the plurality of actuators 908, control system 916 can maintain spatial control of forces 924. For example, control system 916 can adjust certain forces 924 such that comer portions of object 918 experience a plurality of forces 924 with a greater magnitude a magnitude of one force 924 applied to a middle portion of object 918.

[0165] In some aspects, in which electromagnetic object force application system 904 does not include actuators 908, control system 916 can be configured to adjust a voltage, a flux, or a current provided to individual ones of the plurality of mount electromagnetic actuation devices 910 to adjust forces 924 such that the length of gaps 922 are maintained within a predetermined tolerance. In some aspects, control system 916 can selectively adjust a voltage, a flux, or a current provided to mount electromagnetic actuation devices 910 to apply at least one force 924 on a portion of at least one of the plurality of object electromagnetic actuation devices 912 such that object 918 rotates.

[0166] In the example aspect shown in FIG. 9A, electromagnetic object force application system 904 can include control system 916 configured adjust a voltage, a flux, or a current supplied to first through fourth mount electromagnetic actuation devices 910a-910d to adjust first and second forces 924a, 924b produced between first and second mount electromagnetic actuation devices 910a, 910b and the first object electromagnetic actuation device 912a and third and fourth forces 924c, 924d produced between the third and fourth mount electromagnetic actuation devices 910c, 910d and the second object electromagnetic actuation device 912b based on the measuring, such that the first, second, third, and fourth gaps 922a-922dare maintained within a predetermined tolerance. Control system can adjust forces 924a-924d by moving individual ones of actuators 908a-908d and / or adjusting a voltage, a flux, or a current provided to individual ones of the plurality of mount electromagnetic actuation devices 910a-910d. In the example aspect shown in FIG. 9, control system 916 can be configured to selectively adjust a voltage, a flux, or a current provided to the first through fourth mount electromagnetic actuation devices 910a-910d to apply at least one of the first, second, third, and fourth forces 924a-924d on a portion of at least one of the first and second object electromagnetic actuation devices 912a, 912b such that the object 918 rotates. In the example aspect shown in FIG. 9A, control system 916 can be configured to selectively move the first, second, third, and fourth actuators 908a-908d to apply at least one of the first, second, third, and fourth forces 924a-924d on a portion of at least one of the first and second object electromagnetic actuation devices 912a, 912b such that object 918 rotates.

[0167] FIG. 9B shows a portion of system 900, according to some aspects. FIG. 9B can comprise a different view of system 900 shown in FIG. 9A for illustrating additional details. For clarity purposes, new elements may be shown while some may be hidden or unlabeled (e.g., coils are not shown, but are understood to be present). Therefore, unless otherwise noted, descriptions of elements of FIG. 9A can also apply to FIG. 9B. Elements appearing in FIG. 9A that correspond to elements in FIG. 9B can have the same reference numbers.

[0168] In some aspects, upon operation, the plurality of actuators 908 each can contract to provide clearance for object 918 to be loaded onto chuck 902. For example, each of the plurality of actuators 908 can be contracted to provide clearance of a few hundred microns on each side of object 918. Then, in some aspects, the plurality of actuators 908 each can expand to move the plurality of mount electromagnetic actuation devices 910 inwardly toward object electromagnetic actuation devices 912 to form gaps 922 from about 10 microns to about 100 microns. For example, gaps 922 can be about 20 microns, about 25 microns, or about 30 microns. Coarse adjustment and fine adjustment by the plurality of actuators 908 can tune the positions of mount electromagnetic actuation devices 910 to the positioning of the loaded object 918.

[0169] In some aspects, in which electromagnetic object force application system 904 does not include actuators 908, mount electromagnetic actuation devices 910 can be statically located at a distance away from object electromagnetic actuation devices 912 to form gaps 922 over which forces 924 can be applied, while still maintaining clearance for object 918 to be loaded onto chuck 902.

[0170] In some aspects, when chuck 902 begins accelerating, control system 916 can apply a voltage, a flux, or a current to mount electromagnetic actuation devices 910 to produce forces 924 on object electromagnetic actuation devices 912. In some aspects, force 924 can be of a magnitude of about 10% to about 50% of a force that accelerates object 918. In some aspects, forces 924 can be attractive forces that pull object electromagnetic actuation devices 912 toward the corresponding at least one of the mountelectromagnetic actuation devices 910 to keep object 918 stationary relative to chuck 902 while chuck 902 is accelerating, thereby preventing or correcting object slip.

[0171] In some aspects, mount electromagnetic actuation devices 910 each can include a core 930. In some aspects, core 930 can comprise poles 932. As a non-limiting example, core 930 can be shaped to have poles 932 facing a same direction (e.g., C-shaped core). Magnetic flux can be perpendicular to a surface of poles 932. A surface area of poles 932 (e.g., combined area of both poles) can determine a magnitude of magnetic interaction (e.g., a magnitude of magnetic forces 924). Additionally, the magnitude of forces 924 can depend on the size of corresponding gaps 922, in which a smaller gap 922 provides a greater force 924 because force 924 scales according to the reciprocal of the square of gap 922. At larger gaps 924, the corresponding force 924 will be reduced unless a current through the coils around core 930 is increased. As a result, control over positioning and a voltage, a flux, or a current of mount electromagnetic actuation devices 910 is used to prevent object slip and / or damage caused by contact between components. In some aspects, as a failsafe, electromagnetic object force application system 904 can include bumper structures 934 to protect components in the event of a collision.

[0172] In some aspects, measuring system 914 can measure a relative positioning (e.g., gaps 922) between mount electromagnetic actuation devices 910 and corresponding ones of object electromagnetic actuation devices 912. In some aspects, based on the measuring, control system 916 can adjust forces 924 by adjusting the length of gaps 922 by moving corresponding ones of actuators 908, adjusting voltage, flux, or current provided to mount electromagnetic actuation devices 910, or a combination. The feedback loop of measuring gaps 922 and adjusting actuators 908 and / or voltage, flux, or current can provide tight control over a consistent magnitude of forces 924 without creating a contamination risk based on contact between components. Additionally, electromagnetic object force application system 904 can remove some force load off the clamp holding object 918 on chuck 902, thereby further reducing the chance of object slip.

[0173] FIG. 10 shows a method 1000 for operating an electromagnetic object force application system, according to some aspects. In some aspects, the electromagnetic object force application system can be electromagnetic object force application system 904 described with regard to FIGS. 9A and 9B.

[0174] In some aspects, at step S1002, an object (e.g., object 918) can be set on a chuck (e.g., chuck 902). In some aspects, the object can be a reticle, a wafer, or a mirror block.

[0175] In some aspects, at step S1004, first through fourth actuators (e.g., actuators 908a-908d), coupled to corresponding first through fourth mounts (e.g., mounts 906a-906d), can move first through fourth mount electromagnetic actuation devices (e.g., mount electromagnetic actuation devices 910a-910d) laterally inward toward first and second object electromagnetic actuation devices (e.g., object electromagnetic actuation devices 912a, 912b) on respective first and second opposite edges (e.g., edges 920a, 920b) of the object.

[0176] In some aspects, at step S1006, first through fourth gaps (e.g., gaps 922a-922d) can be formed by positioning first and second mount electromagnetic actuation devices adjacent to and away from first object electromagnetic actuation device within a predetermined tolerance and third and fourth mount electromagnetic actuation devices adjacent to and away from second object electromagnetic actuation device within the predetermined tolerance.

[0177] In some aspects, at step S1008, the chuck can be moved with a high acceleration.

[0178] In some aspects, at step S1010, first through fourth gaps can be measured by a measuring system (e.g., measuring system 914).

[0179] In some aspects, at step S 1012, a control system (e.g., control system 916) can adjust a voltage, a flux, or a current supplied to each of the mount electromagnetic actuation devices and / or move the first through fourth actuators to adjust first and second forces (e.g., forces 924a, 924b) produced between first and second mount electromagnetic actuation devices and the first object electromagnetic actuation device and third and fourth forces (e.g., forces 924c, 924d) produced between the third and fourth mount electromagnetic actuation devices and the second object electromagnetic actuation device based on the measuring, such that the first, second, third, and fourth gaps are maintained within the predetermined tolerance. In some aspects, the control system can be configured to selectively adjust a voltage, a flux, or a current provided to the first through fourth mount electromagnetic actuation devices to apply at least one of the first, second, third, and fourth forces on a portion of at least one of the first and second object electromagnetic actuation devices such that the object rotates. In some aspects, the control system can be configured to selectively move the first, second, third, and fourth actuators to apply at least one of the first, second, third, and fourth forces on a portion of at least one of the first and second object electromagnetic actuation devices such that the object rotates.

[0180] The method steps of FIG. 10 can be performed in any conceivable order and it is not required that all steps be performed. Moreover, the method steps of FIG. 10 described above merely reflect an example of steps and are not limiting. That is, further method steps and functions are envisaged based on aspects described in reference to FIGS. 1-6 and 9A-9B.

[0181] Various embodiments of the present systems and methods are disclosed in the subsequent list of numbered clauses:1. A system comprising: a chuck; and an object force application system mounted on the chuck, the object force application system comprising: mounts; actuators each coupled to a corresponding one of the mounts;mount force actuation devices each coupled to a corresponding one of the mounts; first and second object force actuation devices on respective first and second opposite edges of an object, wherein each of the first and second object force actuation devices is located adjacent to and forms a gap with respect to at least a corresponding one of the mount force actuation devices; a measuring system configured to measure the gaps; and a control system configured to adjust a voltage or a current supplied to the mount force actuation devices or to move the actuators to adjust forces produced between each of the first and second object force actuation devices and the corresponding at least one of the mount force actuation devices based on the measuring, such that the gaps are maintained within a predetermined tolerance.2. The system of clause 1, wherein the mount force actuation devices comprise at least one of voltage- controlled electrodes or voltage-controlled, flux-controlled, or current-controlled electromagnets.3. The system of clause 1, wherein the first and second object force actuation devices comprise at least one of an electrically conductive material or a magnetic material.4. The system of clause 1, wherein the first and second object force actuation devices comprise at least one of a coating applied on the object or a plate adhered to the object.5. The system of clause 1, wherein the forces comprise attractive forces configured to pull the first object force actuation device or the second object force actuation device toward the at least corresponding one of the mount force actuation devices.6. The system of clause 1, wherein the control system is configured to selectively adjust a voltage or a current supplied to the mount force actuation devices or selectively move the actuators to apply the forces on a portion of at least one of the first and second object force actuation devices such that the object rotates.7. The system of clause 1, wherein the object comprises a reticle.8. The system of clause 1, wherein the object comprises a wafer.9. The system of clause 1, wherein the object comprises a mirror block.10. A system comprising: a chuck; and an electrostatic object force application system mounted on the chuck, the electrostatic object force application system comprising: mounts; actuators each coupled to a corresponding one of the mounts; mount electrostatic actuation devices each coupled to a corresponding one of the mounts; first and second object electrostatic actuation devices on respective first and second opposite edges of an object, wherein each of the first and second object electrostatic actuation devices islocated adjacent to and forms a gap with respect to at least a corresponding one of the mount electrostatic actuation devices; a measuring system configured to measure the gaps; and a control system configured to adjust a voltage or a current supplied to the mount electrostatic actuation devices or to move the actuators to adjust forces produced between each of the first and second object electrostatic actuation devices and the corresponding at least one of the mount electrostatic actuation devices based on the measuring, such that the gaps are maintained within a predetermined tolerance.11. The system of clause 10, wherein the mount electrostatic actuation devices comprise voltage- controlled electrodes configured to electrostatically interact with the first and second object electrostatic actuation devices.12. The system of clause 10, wherein the first and second object electrostatic actuation devices comprise an electrically conductive material.13. The system of clause 10, wherein the first and second object electrostatic actuation devices comprise first and second coatings applied on the respective first and second opposite edges of the object.14. The system of clause 10, wherein the measuring system comprises a capacitance gauge configured to apply a varying voltage to the mount electrostatic actuation devices to measure a capacitance of the gaps.15. The system of clause 10, wherein the forces comprise attractive forces configured to pull the first object electrostatic actuation device or the second object electrostatic actuation device toward the at least corresponding one of the mount electrostatic actuation devices.16. The system of clause 10, wherein the control system is configured to selectively adjust a voltage or a current supplied to the mount electrostatic actuation devices or selectively move the actuators to apply the forces on a portion of at least one of the first and second object electrostatic actuation devices such that the object rotates.17. The system of clause 10, wherein the object comprises a reticle.18. The system of clause 10, wherein the object comprises a wafer.19. The system of clause 10, wherein the object comprises a mirror block.20. A system comprising: a chuck; and an electromagnetic object force application system mounted on the chuck, the electromagnetic object force application system comprising: mounts; mount electromagnetic actuation devices each coupled to a corresponding one of the mounts;first and second object electromagnetic actuation devices on respective first and second opposite edges of an object, wherein each of the first and second object electromagnetic actuation devices is located adjacent to and forms a gap with respect to at least a corresponding one of the mount electromagnetic actuation devices; a measuring system configured to measure the gaps; and a control system configured to adjust a voltage, a flux, or a current supplied to the mount electromagnetic actuation devices to adjust forces produced between each of the first and second object electromagnetic actuation devices and the corresponding at least one of the mount electromagnetic actuation devices based on the measuring, such that the gaps are maintained within a predetermined tolerance.21. The system of clause 20, further comprising actuators each coupled to a corresponding one of the mounts and configured to be moved by the control system to adjust the forces.22. The system of clause 20, wherein the mount electromagnetic actuation devices comprise voltage- controlled, flux-controlled, or current-controlled electromagnets configured to magnetically interact with the first and second object electromagnetic actuation devices.23. The system of clause 20, wherein the first and second object electromagnetic actuation devices comprise a magnetic material.24. The system of clause 20, wherein the first and second object electromagnetic actuation devices comprise first and second plates adhered to the respective first and second opposite edges of the object.25. The system of clause 20, wherein the forces comprise attractive forces configured to pull the first object electromagnetic actuation device or the second object electromagnetic actuation device toward the at least corresponding one of the mount electromagnetic actuation devices.26. The system of clause 20, wherein the control system is configured to selectively adjust at least one of a voltage, a flux, or a current of one of the mount electromagnetic actuation devices to apply the forces on a portion of at least one of the first and second object electromagnetic actuation devices such that the object rotates.27. The system of clause 20, wherein the object comprises a reticle.28. The system of clause 20, wherein the object comprises a wafer.29. The system of clause 20, wherein the object comprises a mirror block.

[0182] The terms “radiation,” “beam,” “light,” “illumination,” or the like can be used herein to refer to one or more types of electromagnetic radiation, for example, ultraviolet (UV) radiation (for example, having a wavelength X of 365, 248, 193, 157 or 126 nm), extreme ultraviolet (EUV or soft X-ray) radiation (for example, having a wavelength in the range of 5-100 nm such as, for example, 13.5 nm), or hard X-ray working at less than 5 nm, as well as particle beams, such as ion beams or electron beams. Generally, radiation having wavelengths between about 400 to about 700 nm is considered visible radiation; radiationhaving wavelengths between about 780-3000 nm (or larger) is considered IR radiation. UV refers to radiation with wavelengths of approximately 100-400 nm. Within lithography, the term “UV” also applies to the wavelengths that can be produced by a mercury discharge lamp: G-line 436 nm; H-line 405 nm; and / or, I-line 365 nm. Vacuum UV, or VUV (i.e., UV absorbed by gas), refers to radiation having a wavelength of approximately 100-200 nm. Deep UV (DUV) generally refers to radiation having wavelengths ranging from 126 nm to 428 nm, and in some aspects, an excimer laser can generate DUV radiation used within a lithographic apparatus. It should be appreciated that radiation having a wavelength in the range of, for example, 5-20 nm relates to radiation with a certain wavelength band, of which at least part is in the range of 5-20 nm.

[0183] Although some aspects of the present disclosure are described in the context of lithographic apparatuses in the manufacture of ICs, it should be understood that lithographic apparatuses described herein can be used in other applications, for example, in the manufacture of integrated optical systems, guidance and detection patterns for magnetic domain memories, flat-panel displays, UCDs, thin-fdm magnetic heads, etc. Those skilled in the art will appreciate that, in the context of such alternative applications, any use of the terms “wafer” or “die” herein can be considered as specific examples of the more general terms “substrate” or “target portion”, respectively. A substrate can be processed before or after exposure in, for example, a track unit (a tool that typically applies a layer of resist to a substrate and develops the exposed resist) and / or a metrology unit. Where applicable, aspects disclosed herein can be applied to such and other substrate processing tools. Furthermore, a substrate can be processed more than once, for example in order to create a multi-layer IC, so that the term substrate used herein can also refer to a substrate that already contains multiple processed layers.

[0184] Furthermore, although some aspects of the present disclosure are described in the context of optical lithography, it should be understood that aspects of the present disclosure are not limited to optical lithography. For example, in imprint lithography, a topography in a patterning device defines the pattern created on a substrate. The topography of the patterning device can be pressed into a layer of resist supplied to the substrate whereupon the resist is cured by applying electromagnetic radiation, heat, pressure or a combination thereof. The patterning device is moved out of the resist leaving a pattern in it after the resist is cured.

[0185] It is to be understood that the phraseology or terminology herein is for the purpose of description and not of limitation, such that the terminology or phraseology of the present specification is to be interpreted by those skilled in relevant art(s) in light of the teachings herein.

[0186] The present disclosure has been described above with the aid of functional building blocks illustrating the implementation of specified functions and relationships thereof. The boundaries of these functional building blocks have been arbitrarily defined herein for the convenience of the description.Alternate boundaries can be defined so long as the specified functions and relationships thereof are appropriately performed. The foregoing description of specific aspects will so fully reveal the general nature of the present disclosure that others can, by applying knowledge within the skill of the art, readily modify and / or adapt for various applications such specific aspects, without undue experimentation and without departing from the general concept of the present disclosure. Therefore, such adaptations and modifications are intended to be within the meaning and range of equivalents of the disclosed aspects, based on the teaching and guidance presented herein.

[0187] It is to be understood that the Detailed Description section, and not the Summary and Abstract sections, is intended to be used to interpret the claims. The Summary and Abstract sections can set forth one or more, but not necessarily all, aspects of the present disclosure as contemplated by the inventor(s), and thus, are not intended to limit the present disclosure and the appended claims in any way. The breadth and scope of the protected subject matter should not be limited by any of the above-described aspects, but should be defined in accordance with the following claims and their equivalents.

Claims

CLAIMS1. A system comprising: a chuck; and an object force application system mounted on the chuck, the object force application system comprising: mounts; actuators each coupled to a corresponding one of the mounts; mount force actuation devices each coupled to a corresponding one of the mounts; first and second object force actuation devices on respective first and second opposite edges of an object, wherein each of the first and second object force actuation devices is located adjacent to and forms a gap with respect to at least a corresponding one of the mount force actuation devices; a measuring system configured to measure the gaps; and a control system configured to adjust a voltage or a current supplied to the mount force actuation devices or to move the actuators to adjust forces produced between each of the first and second object force actuation devices and the corresponding at least one of the mount force actuation devices based on the measuring, such that the gaps are maintained within a predetermined tolerance.

2. The system of claim 1, wherein: the mount force actuation devices comprise at least one of voltage-controlled electrodes or voltage- controlled, flux-controlled, or current-controlled electromagnets; the first and second object force actuation devices comprise at least one of an electrically conductive material or a magnetic material; and the first and second object force actuation devices comprise at least one of a coating applied on the object or a plate adhered to the object.

3. The system of claim 1, wherein the forces comprise attractive forces configured to pull the first object force actuation device or the second object force actuation device toward the at least corresponding one of the mount force actuation devices.

4. The system of claim 1, wherein the control system is configured to selectively adjust a voltage or a current supplied to the mount force actuation devices or selectively move the actuators to apply the forces on a portion of at least one of the first and second object force actuation devices such that the object rotates.

5. The system of claim 1, wherein the object comprises a reticle, a wafer, or a mirror block.

6. A system comprising: a chuck; and an electrostatic object force application system mounted on the chuck, the electrostatic object force application system comprising: mounts; actuators each coupled to a corresponding one of the mounts; mount electrostatic actuation devices each coupled to a corresponding one of the mounts; first and second object electrostatic actuation devices on respective first and second opposite edges of an object, wherein each of the first and second object electrostatic actuation devices is located adjacent to and forms a gap with respect to at least a corresponding one of the mount electrostatic actuation devices; a measuring system configured to measure the gaps; and a control system configured to adjust a voltage or a current supplied to the mount electrostatic actuation devices or to move the actuators to adjust forces produced between each of the first and second object electrostatic actuation devices and the corresponding at least one of the mount electrostatic actuation devices based on the measuring, such that the gaps are maintained within a predetermined tolerance.

7. The system of claim 6, wherein: the mount electrostatic actuation devices comprise voltage-controlled electrodes configured to electrostatically interact with the first and second object electrostatic actuation devices; the first and second object electrostatic actuation devices comprise an electrically conductive material; and the first and second object electrostatic actuation devices comprise first and second coatings applied on the respective first and second opposite edges of the object.

8. The system of claim 6, wherein the measuring system comprises a capacitance gauge configured to apply a varying voltage to the mount electrostatic actuation devices to measure a capacitance of the gaps.

9. The system of claim 6, wherein the forces comprise attractive forces configured to pull the first object electrostatic actuation device or the second object electrostatic actuation device toward the at least corresponding one of the mount electrostatic actuation devices.

10. The system of claim 6. wherein the control system is configured to selectively adjust a voltage or a current supplied to the mount electrostatic actuation devices or selectively move the actuators to apply the forces on a portion of at least one of the first and second object electrostatic actuation devices such that the object rotates.

11. The system of claim 6, wherein the object comprises a reticle, a wafer, or a mirror block.

12. A system comprising: a chuck; and an electromagnetic object force application system mounted on the chuck, the electromagnetic object force application system comprising: mounts; mount electromagnetic actuation devices each coupled to a corresponding one of the mounts; first and second object electromagnetic actuation devices on respective first and second opposite edges of an object, wherein each of the first and second object electromagnetic actuation devices is located adjacent to and forms a gap with respect to at least a corresponding one of the mount electromagnetic actuation devices; a measuring system configured to measure the gaps; and a control system configured to adjust a voltage, a flux, or a current supplied to the mount electromagnetic actuation devices to adjust forces produced between each of the first and second object electromagnetic actuation devices and the corresponding at least one of the mount electromagnetic actuation devices based on the measuring, such that the gaps are maintained within a predetermined tolerance.

13. The system of claim 12, further comprising actuators each coupled to a corresponding one of the mounts and configured to be moved by the control system to adjust the forces.

14. The system of claim 12, wherein: the mount electromagnetic actuation devices comprise voltage-controlled, flux-controlled, or current-controlled electromagnets configured to magnetically interact with the first and second object electromagnetic actuation devices; the first and second object electromagnetic actuation devices comprise a magnetic material; and the first and second object electromagnetic actuation devices comprise first and second plates adhered to the respective first and second opposite edges of the object.

15. The system of claim 12, wherein: the forces comprise attractive forces configured to pull the first object electromagnetic actuation device or the second object electromagnetic actuation device toward the at least corresponding one of the mount electromagnetic actuation devices; the control system is configured to selectively adjust at least one of a voltage, a flux, or a current of one of the mount electromagnetic actuation devices to apply the forces on a portion of at least one of the first and second object electromagnetic actuation devices such that the object rotates; and the object comprises a reticle, a wafer, or a mirror block.

Images