Electromotive force braking in lithography equipment

Abstract

The braking system may include a moving frame, one or more balance masses, one or more actuators, and one or more mechanical buffers. The moving frame can move with a predetermined kinetic energy. One or more balance masses can absorb the reaction forces acted upon by the moving frame. One or more actuators can drive the moving frame and stop its movement through braking to prevent collision damage in error scenarios. One or more actuators may be electrically short-circuited to generate an electromotive braking force opposite to the direction of the moving frame's movement in order to reduce the kinetic energy of the moving frame and reduce the braking distance of the moving frame. One or more mechanical buffers can absorb the remaining kinetic energy of the moving frame that remains after one or more actuators have completed their braking actions.

Description

[Technical Field]

[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS] This application claims priority to U.S. Application 63 / 580,237 filed on September 1, 2023, which is incorporated herein by reference in its entirety.

[0002] [Technical Field] The present disclosure relates to a driven stage, for example, a stage for supporting a reticle used in a lithography apparatus and system. [Background Art]

[0003] A lithography apparatus is an apparatus configured to apply a desired pattern onto a substrate. The lithography apparatus can be used, for example, in the manufacture of integrated circuits (ICs). A lithography apparatus can 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, for example.

[0004] To project a pattern onto a substrate, a lithography apparatus can use electromagnetic radiation. The wavelength of this radiation determines the minimum size of features that can be formed on the substrate. Lithography apparatuses using extreme ultraviolet (EUV) radiation having a wavelength in the range of 4-20 nm (e.g., 6.7 nm or 13.5 nm) can be used to form smaller features on a substrate than lithography apparatuses using radiation with a wavelength of 193 nm, for example. [Summary of the Invention] [Problem to be Solved by the Invention]

[0005] A lithography system can only output a finite number of manufactured devices within a given time frame. High-speed scanning of the wafer stage and reticle stage can increase the speed of manufacturing. However, efforts to increase the speed of the moving stage may result in an increase in the braking distance of the moving stage. Such an increase in braking distance can lead to collisions that cause mechanical damage in existing lithography systems. For example, current mechanical buffers may not be able to independently absorb the kinetic energy of the moving stage, and thus cannot prevent the moving stage from damaging other components within the limited volume of existing lithography systems.

[0006] Thus, it is desirable to enhance braking capabilities to achieve both increased lithography manufacturing speed and throughput. Electromagnetic actuators for wafers and reticle stages can provide the electromotive braking force described herein. [Means for solving the problem]

[0007] In some aspects, a lithography apparatus may include a lighting system, a patterning system, a projection system, and a reticle stage. The lighting system may be configured to generate a beam of radiation. The patterning system may include a reticle and may be configured to impart a pattern to the beam. The projection system may be configured to project the patterned beam onto a substrate. The reticle stage may include a moving frame, one or more balance masses, one or more actuators, and one or more mechanical buffers. The moving frame can move with a predetermined amount of kinetic energy. One or more balance masses can absorb the reaction force acted upon by the moving frame. One or more actuators can drive the moving frame and stop its movement through braking according to error scenarios to prevent collision damage. One or more actuators may be electrically short-circuited to generate an electromotive braking force opposite to the direction of the moving frame's movement in order to reduce the kinetic energy of the moving frame and reduce the braking distance of the moving frame. One or more mechanical buffers can absorb the remaining kinetic energy of the moving frame after one or more actuators have completed their braking action.

[0008] In some aspects, a braking system may include a moving frame, one or more balance masses, one or more actuators, and one or more mechanical buffers. The moving frame can move with a predetermined amount of kinetic energy. One or more balance masses can absorb the reaction forces acted upon by the moving frame. One or more actuators can drive the moving frame and stop its movement through braking according to error scenarios to prevent collision damage. One or more actuators may be electrically short-circuited to generate an electromotive braking force opposite to the direction of the moving frame's movement in order to reduce the kinetic energy of the moving frame and reduce the braking distance of the moving frame. One or more mechanical buffers can absorb the remaining kinetic energy of the moving frame that remains after one or more actuators have completed their braking actions.

[0009] In some aspects, the braking method may include applying a current to one or more actuator coils so that they interact with magnetic fields from one or more magnets in the vicinity of one or more actuator coils. The braking method may further include generating a force to drive the moving frame in the lithography apparatus in a first direction. The braking method may further include shorting one or more actuator coils during the movement of the moving frame, depending on the error scenario, to prevent collision damage. The braking method may further include inducing a current in one or more actuator coils, brought about by magnetic fields from one or more magnets. The braking method may further include generating a magnetic field in one or more actuator coils opposite to the magnetic field from one or more magnets in order to generate an electromotive braking force in a second direction opposite to the first direction of movement of the moving frame. The braking method may further include reducing the speed of the moving frame before it collides with one or more mechanical buffers.

[0010] Further features of various aspects of this disclosure are described in detail below with reference to the accompanying drawings. It is understood that this 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 art based on the teachings contained herein. [Brief explanation of the drawing]

[0011] The accompanying drawings incorporated herein and forming part of the specification are used to illustrate the disclosure and, together with the description herein, to illustrate the principles of the disclosure so that those skilled in the art may manufacture and use the aspects described herein.

[0012] Figure 1A shows a reflective lithography apparatus from several angles.

[0013] Figure 1B shows a transmission lithography apparatus from several angles.

[0014] Figure 1C shows a lithography cell relating to several aspects.

[0015] Figures 2 and 3 show the reticle stage from several angles.

[0016] Figure 4 shows a reticle exchange device from several angles.

[0017] Figure 5 shows the driven stages from several perspectives.

[0018] Figures 6A and 6B show the actuator device from several angles.

[0019] Figures 7A and 7B show the mechanical buffer in several aspects.

[0020] Figure 8 shows a flowchart for braking methods relating to several aspects.

[0021] The features of the present disclosure will become more apparent from the following detailed description when interpreted in conjunction with the drawings (in which like reference numerals consistently represent corresponding elements). Like reference numerals in the drawings generally indicate identical, functionally similar, and / or structurally similar elements. In addition, the leftmost digit of a reference numeral generally indicates the drawing in which the reference numeral first appears. Unless otherwise stated, the drawings provided throughout the disclosure should not be construed as true to actual dimensions. MODE FOR CARRYING OUT THE INVENTION

[0022] References described herein to "one aspect", "an aspect", "an exemplary aspect", "an embodiment", and the like, indicate that the described aspect may include a particular feature, structure, or characteristic, but not all aspects necessarily include the particular feature, structure, or characteristic. Furthermore, such phrases do not necessarily refer to the same aspect. Furthermore, when a particular feature, structure, or characteristic is described in connection with an aspect, it is understood that implementing such feature, structure, or characteristic in connection with other aspects is within the knowledge of those skilled in the art regardless of whether it is explicitly described or not.

[0023] Spatially relative terms such as "lower" (e.g., beneath, below, lower) and "upper" (e.g., above, on, upper) may be used herein to facilitate describing the relationship of one illustrated element or feature to another element or feature. Spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation illustrated in the drawings. The device may be oriented in different directions (rotated 90 degrees or other orientations), and the spatially relative terms used herein may be interpreted accordingly in a corresponding manner.

[0024] The terms "about", "approximately", and the like may be used herein to refer to a value of a given quantity that can vary based on a particular technology. Based on the particular technology, the terms "about", "approximately", and the like can, for example, refer to a value of a given quantity that varies within 10-30% of the value (e.g., ±10%, ±20%, or ±30% of the value).

[0025] Aspects of the present disclosure may be implemented as hardware, firmware, software, or any combination thereof. Aspects of the present disclosure may be implemented as instructions stored on a computer-readable medium, which may be read and executed by one or more processors. A machine-readable medium may include any mechanism for storing or transmitting information in a form readable by an apparatus (e.g., a computing device). For example, a machine-readable medium may include read-only memory (ROM), random access memory (RAM), magnetic disk storage media, optical storage media, flash memory devices, electrical / optical / acoustic or other forms of transmitted signals (e.g., carrier waves, infrared signals, digital signals, etc.), and the like. Furthermore, firmware, software, routines, and / or instructions may be described herein as performing certain actions. However, it should be understood that such description is merely for convenience, and such actions are caused by a computing device, processor, controller or other device that executes the firmware, software, routines, instructions, etc. The term "machine-readable medium" may be interchangeable with similar terms such as "computer program product", "computer-readable medium", "non-transitory computer-readable medium", and the like. The term "non-transitory" may be used herein to characterize one or more forms of computer-readable media, excluding transient propagating signals.

[0026] Before describing such aspects in detail, an example environment in which aspects of the present disclosure may be implemented is provided for reference.

[0027] Example Lithography System

[0028] Figures 1A and 1B show lithography apparatus 100 and lithography apparatus 100', respectively, in which aspects of the present disclosure may be implemented. Each of lithography apparatus 100 and lithography apparatus 100' includes the following elements: an illumination system (illuminator) IL configured to adjust a radiation beam B (e.g., deep ultraviolet or extreme ultraviolet radiation); a support structure (e.g., a mask table) MT configured to support a patterning device (e.g., a mask, reticle, or dynamic patterning device) MA and connected to a first positioner PM configured to precisely position the patterning device MA; and a substrate table (e.g., a wafer table) WT configured to hold a substrate (e.g., a resist-coated wafer) W and connected to a second positioner PW configured to precisely position the substrate W. Lithography apparatuses 100 and 100' also include a projection system PS configured to project a pattern formed on a radiation beam B by a patterning device MA onto a target portion (e.g., including one or more dies) C of a substrate W. In lithography apparatus 100, the patterning device MA and projection system PS are reflective. In lithography apparatus 100', the patterning device MA and projection system PS are transmissive.

[0029] The illumination system IL may include various types of optical components, such as refractive, reflective, reflexive, magnetic, electromagnetic, electrostatic, and other types of optical components, or any combination thereof, for directing, shaping, or controlling the radiant beam B.

[0030] The support structure MT holds the patterning device MA in a manner that depends on other conditions such as the orientation of the patterning device MA relative to the reference frame, the design of at least one of the lithography apparatuses 100 and 100', and whether the patterning device MA is held in a vacuum environment. The support structure MT may use mechanical, vacuum, electrostatic, or other clamping techniques to hold the patterning device MA. The support structure MT may be, for example, a fixed or movable frame or table. By using sensors, the support structure MT can reliably position the patterning device MA in a desired position, for example, relative to the projection system PS.

[0031] The term “patterning device” MA should be broadly interpreted to refer to any device that can be used to form a pattern on the cross-section of a radiation beam B, for example, to generate a pattern on a target portion C of a substrate W. The pattern formed on the radiation beam B may correspond to a specific functional layer in the device that is generated on the target portion C to form an integrated circuit.

[0032] The patterning device MA may be transmissive (e.g., as in lithography apparatus 100' in Figure 1B) or reflective (e.g., as in lithography apparatus 100 in Figure 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, Levenson phase-shift, or halftone phase-shift, and various hybrid mask types. An example of a programmable mirror array utilizes a matrix arrangement of small mirrors that can be individually tilted to reflect the incident beam in different directions. The tilted mirrors form a pattern (reflected by the matrix of small mirrors) on the emitted beam B.

[0033] The term "projection system" PS can encompass any type of projection system, including refractive, reflective, refracting, magnetic, electromagnetic, electrostatic optical systems, or any combination thereof, appropriate for the exposure radiation used and other factors such as the use of immersion liquid or vacuum on the substrate W. A vacuum environment may be used for EUV or electron beam radiation because other gases may absorb excess radiation or electrons. For this reason, a vacuum environment may be provided throughout the beam path by vacuum walls and vacuum pumps.

[0034] The lithography apparatus 100 and / or lithography apparatus 100' may be of a type having two (dual stage) or more substrate tables WT (and / or two or more mask tables). In such a “multi-stage” apparatus, additional substrate tables WT may be used in parallel, or preparation steps may be performed on one or more tables while one or more other substrate tables WT are being used for exposure. In some situations, the additional tables may not be substrate tables WT.

[0035] The lithography apparatus may be of a type in which at least a portion of the substrate may be covered with a liquid having a relatively high refractive index, such as water, to fill the space between the projection system and the substrate. The immersion liquid may also be applied to other spaces in the lithography apparatus, such as between the mask and the projection system. Immersion technique is a well-known technique for increasing the numerical aperture of the projection system. The term "immersion" as used here does not mean that structures such as the substrate must be submerged in the liquid. For example, the liquid may be located between the projection system and the substrate during exposure.

[0036] Referring to Figures 1A and 1B, the illuminator IL receives the radiated beam from the radiated source SO. For example, if the source SO is an excimer laser, the source SO and the lithography apparatus 100, 100' may be physically separate. In such a case, the source SO is not considered to constitute part of the lithography apparatus 100 or 100', and the radiated beam B is delivered from the source SO to the illuminator IL by a beam delivery system BD (see Figure 1B), which includes, for example, appropriate directional mirrors and / or beam expanders. In other cases, for example, if the source SO is a mercury lamp, the source SO may be part of the lithography apparatus 100, 100'. The radiated system may comprise the source SO, the illuminator IL, and / or the beam delivery system BD.

[0037] The illuminator IL may include an adjuster AD (see Figure 1B) for adjusting the angular intensity distribution of the radiated beam. Generally, at least the outer radius range and / or inner radius range (generally denoted as "σ-outer" and "σ-inner," respectively) of the intensity distribution at the pupil plane of the illuminator can be adjusted. In addition, the illuminator IL may comprise various other components such as an integrator IN and a capacitor CO (see Figure 1B). The illuminator IL may be used to adjust the radiated beam B to have desired uniformity and intensity distribution in cross-section.

[0038] Referring to Figure 1A, a radiant beam B is incident on a patterning device (e.g., a mask) MA held on a support structure (e.g., a mask table) MT, and a pattern is formed by the patterning device MA. In the lithography apparatus 100, the radiant beam B is reflected from the patterning device (e.g., a mask) MA. After being reflected from the patterning device (e.g., a mask) MA, the radiant beam B passes through a projection system PS that focuses the radiant beam B onto a target portion C of the substrate W. A second positioner PW and position sensors IF2 (e.g., an interference device, a linear encoder, or a capacitive sensor) can precisely drive the substrate table WT (e.g., to position different target portions C in the path of the radiant beam B). Similarly, a first positioner PM and other position sensors IF1 can be used to precisely position the patterning device (e.g., a mask) MA relative to the path of the radiant beam B. The patterning device (e.g., mask) MA and the substrate W can be aligned using mask alignment marks M1, M2 and substrate alignment marks P1, P2.

[0039] Referring to Figure 1B, the radiated beam B is incident on a patterning device (e.g., mask MA) held on a support structure (e.g., mask table MT), and a pattern is formed by the patterning device. After passing through the mask MA, the radiated beam B passes through a projection system PS that focuses the beam onto a target portion C of the substrate W. The projection system has a pupil-conjugate PPU relative to the pupil IPU of the illumination system. The radiated portion is emitted from the intensity distribution at the pupil IPU of the illumination system, passes through the mask pattern without being affected by diffraction at the mask pattern, and generates an image of the intensity distribution at the pupil IPU of the illumination system.

[0040] The projection system PS projects an image of a mask pattern MP onto a photoresist layer coated on a substrate W. Here, the image is formed by a diffracted beam generated from the mask pattern MP by radiation from the intensity distribution. For example, the mask pattern MP may include an array of lines and spaces. Diffracted radiation from a different array than zero-order diffraction produces a divergent diffracted beam with a change in direction perpendicular to the lines. The non-diffracted beam (i.e., the so-called zero-order diffracted beam) passes through the pattern without a change in the direction of transmission. The zero-order diffracted beam passes through the upper lens or group of upper lenses of the projection system PS upstream of the pupil-conjugate PPU of the projection system PS and reaches the pupil-conjugate PPU. The portion of the intensity distribution on the surface of the pupil-conjugate PPU associated with the zero-order diffracted beam is an image of the intensity distribution in the pupil-IPU of the illumination system IL. The aperture device PD is substantially located on the surface of the projection system PS containing the pupil-conjugate PPU, for example.

[0041] The projection system PS is configured to capture a zero-order diffraction beam, a primary diffraction beam, and / or a higher-order diffraction beam (not shown) (e.g., using a lens or lens group L). In some aspects, dipole illumination may be used to image a line pattern extending in a direction perpendicular to the line in order to take advantage of the resolution-enhancing effect of dipole illumination. For example, a primary diffraction beam interferes with the corresponding zero-order diffraction beam at the wafer W level to produce an image of the line pattern MP with the highest possible resolution and process window (i.e., usable depth of field in combination with an acceptable exposure dose deviation). In some aspects, astigmatism can be reduced by providing an radiating pole (not shown) in the quadrant opposite to the illumination system pupil IPU. Furthermore, in some aspects, astigmatism can be reduced by blocking the zero-order beam in the projection system's pupil-conjugate PPU associated with the radiating pole in the opposite quadrant. This is described in more detail in U.S. Patent No. 7,511,799B2, issued on March 31, 2009, which is incorporated herein by reference in its entirety.

[0042] A second positioner PW and position sensor IFD (e.g., an interference device, linear encoder, or capacitive sensor) can precisely drive the substrate table WT (e.g., to position different target portions C along the path of the radiation beam B). Similarly, a first positioner PM and other position sensors (not shown in Figure 1B) can be used to precisely position the mask MA relative to the path of the radiation beam B (e.g., after mechanical retrieval from the mask library or during scanning).

[0043] Generally, the movement of the mask table MT can be achieved by long-stroke modules (coarse positioning) and short-stroke modules (fine positioning) that constitute part of the first positioner PM. Similarly, the movement of the substrate table WT can be achieved using long-stroke modules and short-stroke modules that constitute part of the second positioner PW. In the case of a stepper (not a scanner), the mask table MT may be connected to or fixed to a short-stroke actuator. The mask MA and substrate W can be aligned using mask alignment marks M1, M2 and substrate alignment marks P1, P2. The substrate alignment marks occupy dedicated target areas as shown in the figure, but may be placed in the space between the target areas (known as scribe line alignment marks). Similarly, in situations where multiple dies are provided on the mask MA, the mask alignment marks may be placed between the dies.

[0044] The mask table MT and patterning device MA may be placed in a vacuum chamber V, which can be used by an in-vacuum robot IVR to drive the patterning device, such as a mask, both inside and outside the vacuum chamber. Alternatively, if the mask table MT and patterning device MA are outside the vacuum chamber, an out-of-vacuum robot may be used for various transfer operations, similar to the in-vacuum robot IVR. Both in-vacuum and out-of-vacuum robots can be calibrated to smoothly transfer any payload (e.g., a mask) to a fixed kinematic mount on a transfer station.

[0045] Lithography apparatuses 100 and 100' can be used in at least one of the following modes: 1. In step mode, the support structure (e.g., mask table) MT and substrate table WT are kept substantially stationary while the entire pattern formed on the radiation beam B is projected onto the target portion C at once (i.e., single static exposure). Then, the substrate table WT is shifted in the X and / or Y directions so that different target portions C can be exposed. 2. In scan mode, the support structure (e.g., mask table) MT and the substrate table WT are scanned simultaneously while the pattern formed on the radiation beam B is projected onto the target portion C (i.e., single dynamic exposure). The speed and direction of the substrate table WT relative to the support structure (e.g., mask table) MT can be determined by the magnification and image inversion characteristics of the projection system PS. 3. In other modes, the support structure (e.g., mask table) MT is kept substantially stationary while holding the programmable patterning device, and the substrate table WT is driven or scanned while the pattern formed on the radiated beam B is projected onto the target portion C. A pulsed radiation source SO may be used, and the programmable patterning device is updated as needed after each movement of the substrate table WT or between consecutive radiation pulses during scanning. This mode of operation can be readily applied to maskless lithography utilizing programmable patterning devices such as programmable mirror arrays.

[0046] Combinations and / or variations of the above usage modes, or entirely different usage modes, may be used.

[0047] In some respects, the lithography apparatus 100 includes an EUV source configured to generate a beam of EUV radiation for extreme ultraviolet (EUV) lithography. Generally, the EUV source is configured in a radiation system, and the corresponding illumination system is configured to adjust the EUV radiation beam of the EUV source.

[0048] In some respects, the lithography apparatus 100' includes a DUV source configured to generate a beam of DUV radiation for deep ultraviolet (DUV) lithography. Generally, the DUV source is configured in the radiation system, and the corresponding illumination system is configured to adjust the DUV radiation beam of the DUV source.

[0049] Examples of lithography cells

[0050] Figure 1C shows a lithography cell 102, also referred to as a lithocell or cluster, relating to several aspects. A lithography apparatus 100 or 100' may constitute part of the lithography cell 102. The lithography cell 102 may also include one or more devices that perform pre-exposure and post-exposure processes on the substrate. Conventionally, these include a spin coater SC for forming a resist layer, a developer DE for developing the exposed resist, a cooling plate CH, and a bake plate BK. A substrate handler or robot RO picks up the substrate from input / output ports I / O1 and I / O2, moves them between different processing units, and transports them to the loading bay LB of the lithography apparatus 100 or 100'. These devices, often collectively referred to as tracks, are under the control of a track control unit TCU, which is controlled by a monitoring and control system SCS, which also controls the lithography apparatus via a lithography control unit LACU. Thus, different devices can operate to maximize throughput and processing efficiency.

[0051] Example of a reticle stage

[0052] Figures 2 and 3 show the reticle stage 200 from several perspectives. The reticle stage 200 may include a top stage surface 202, a bottom stage surface 204, a side stage surface 206, and a clamp 300. In some perspectives, the reticle stage 200 with the clamp 300 may be implemented in a lithography apparatus LA. For example, the reticle stage 200 may also be a support structure MT in the lithography apparatus LA. In some perspectives, the clamp 300 may be positioned on the top stage surface 202. For example, as shown in Figure 2, the clamp 300 may be positioned in the center of the top stage surface 202 with the clamp front side 302 oriented perpendicularly away from the top stage surface 202.

[0053] In some lithography apparatuses, such as the lithography apparatus LA, a reticle stage 200 with clamps 300 may be used to hold and position a reticle 408 for scanning or patterning operations. In one example, the reticle stage 200 may rely on a powerful drive, a large balance mass, and a heavy frame to support it. In one example, the reticle stage 200 may have a large inertia to propel and position a reticle 408 weighing approximately 0.5 kg, and may exceed 500 kg. Acceleration and deceleration forces may be provided by a linear motor driving the reticle stage 200 to achieve the reciprocating motion of the reticle 408 that is typically performed in lithographic scanning or patterning operations.

[0054] In some aspects, as shown in Figures 2 and 3, the reticle stage 200 may include a first encoder 212 and a second encoder 214 for positioning operations. For example, the first and second encoders 212 and 214 may be interferometers. The first encoder 212 may be mounted along a first direction of the reticle stage 200, for example, the transverse direction (i.e., the X direction). The second encoder 214 may be mounted along a second direction of the reticle stage 200, for example, the longitudinal direction (i.e., the Y direction). In some aspects, as shown in Figures 2 and 3, the first encoder 212 may be orthogonal to the second encoder 214.

[0055] As shown in Figures 2 and 3, the reticle stage 200 may include a clamp 300. The clamp 300 is configured to hold the reticle 408 within a fixed surface on the reticle stage 200. The clamp 300 may include a clamp front side 302 and be positioned on the top stage surface 202. In some aspects, the clamp 300 may be mechanical, vacuum, electrostatic, or other suitable clamping techniques to hold and secure the object. In some aspects, the clamp 300 may be an electrostatic clamp configured to electrostatically clamp (i.e., hold) an object, e.g., the reticle 408 (Figure 4), in a vacuum environment. For EUV generation performed in a vacuum environment, it may be difficult to use a vacuum clamp to clamp a mask or reticle. Instead, an electrostatic clamp may be used. For example, the clamp 300 may include electrodes, a resistive layer on the electrodes, an insulating layer on the resistive layer, and a bar protruding from the insulating layer. During use, a voltage (e.g., several kV) may be applied to the clamp 300. A current may then flow through the resistive layer such that the voltage on the upper surface of the resistive layer becomes substantially the same as the voltage at the electrodes, generating an electric field. Additionally, Coulomb forces (attractive forces between electrically oppositely charged particles) attract the object to the clamp 300, holding it in place. In some respects, the clamp 300 may be made of a rigid material such as metal, an insulator, a ceramic, or a combination thereof.

[0056] Example of a reticle exchange device

[0057] Figure 4 shows the reticle exchange device 401 in several aspects. The reticle exchange device 401 may be configured to minimize reticle exchange time, particle generation, and contact force or stress from the clamp 300 and / or reticle 408 in order to reduce damage to the clamp 300 and reticle 408 and to increase the overall throughput of the reticle exchange process in, for example, a lithography apparatus LA.

[0058] The reticle exchange device 401 may include a reticle stage 200, a clamp 300, and a vacuum robot 400. The vacuum robot 400 may include a reticle handler 402.

[0059] In some respects, the reticle handler 402 may also be a rapid exchange device (RED) configured to rotate efficiently and minimize reticle exchange time. For example, the reticle handler 402 can save time by moving multiple reticles from one position to another substantially simultaneously rather than serially.

[0060] In some respects, the reticle handler 402 may include one or more reticle handler arms 404. The reticle handler arms 404 may include a reticle base plate 406. The reticle base plate 406 may be configured to hold an object, for example, a reticle 408.

[0061] In some respects, the reticle baseplate 406 may also be an extreme ultraviolet inner pod (EIP) for the reticle. In some respects, the reticle baseplate 406 includes the reticle baseplate front side 407, and the reticle 408 includes the reticle back side 409.

[0062] In some aspects, the reticle base plate 406 can hold the reticle 408 such that the reticle base plate front side 407 and the reticle back side 409 face the top stage surface 202 and the clamp front side 302, respectively. For example, the reticle base plate front side 407 and the reticle back side 409 may face each other perpendicularly away from the top stage surface 202 and the clamp front side 302.

[0063] In some aspects, the reticle handler arms 404 may be arranged symmetrically with respect to the reticle handler 402, as shown in Figure 4. For example, the reticle handler arms 404 may be spaced about 90 degrees, 120 degrees, or 180 degrees apart from each other. In some aspects, the reticle handler arms 404 may be arranged asymmetrically with respect to the reticle handler 402. For example, two reticle handler arms 404 may be spaced about 135 degrees apart from each other, and other two reticle handler arms 404 may be spaced about 90 degrees apart from each other.

[0064] In some respects, during the reticle exchange process, the reticle stage 200 with clamp 300 can be adjusted in multi-stage operation (e.g., long-stroke stage (coarse), short-stroke stage (fine)).

[0065] Examples of driven stages

[0066] Some aspects described herein provide structures and functions to address the challenges related to preventing mechanical impact damage in lithography equipment.

[0067] Figure 5 shows the stage 500 for supporting the object 502, relating to several aspects. In some aspects, the stage 500 may represent different views of the reticle stage 200 to highlight additional details. The stage 500 may comprise the object 502, a moving frame 504, a base frame 506, a balance mass 508, an actuator device 510, and mechanical buffers 512a and 512b.

[0068] In some respects, the stage 500 can be used in a lithography apparatus LA (Figure 1), a lithography cell (e.g., an arrangement of multiple lithography apparatuses), an inspection apparatus, or any apparatus that generally has a stage implementation for supporting and driving objects. For example, the stage 500 may represent a specific implementation of a wafer table WT or a mask table MT (Figure 1).

[0069] In some respects, the moving frame 504 may also be the structure being driven (for example, for the coarse movement of the object 502). In a lithography manufacturing process, the object 502 may be a reticle, a wafer, etc. Furthermore, the stage 500 may also include an additional moving budget for moving the object 502 back and forth to and from the loading area. Thus, the moving frame 504 can handle the coarse movement of the stage 500 on the order of tens, hundreds, or thousands of millimeters, for example. Other distances may be chosen based on suitability for a particular implementation.

[0070] In some aspects, object 502 can be temporarily attached to the moving frame 504 by pressing it onto the frame. This can be achieved by vacuum clamping (suction force), electrostatic clamping (electrostatic force), mechanical clamping, etc. Under ideal conditions, mutual friction between object 502 (e.g., reticle) and the moving frame 504 (e.g., chuck) can ensure that there is no slippage between them. However, mechanical stress due to high acceleration can induce some slippage, leading to printing errors. Errors can be extremely detrimental, as thousands of device products may be lost by the time the error is detected.

[0071] In some aspects, the moving frame 504 may be coupled to a balance mass 508 in its vicinity. In some aspects, the balance mass 508 may be configured to mimic coarse motion, dampen, and return the moving frame 504 to an equilibrium position. In some aspects, the balance mass 508 may be configured to absorb the reaction force acted upon it by the moving frame 504. In some aspects, the balance mass 508 may be supported by a base frame 506 while still allowing relative movement between the moving frame 504 and the balance mass 508. The movement of the moving frame 504 may be restricted to an axis (e.g., the Y-axis) using guide rails or a non-contact method (e.g., magnetic levitation) (guide devices not shown). Coordinate axes X and Y are provided as non-limiting examples.

[0072] In some respects, the actuator device 510 can be responsible for the course motion of the moving frame 504. The actuator device 510 may be configured to accelerate the moving frame 504 by providing a driving force between the moving frame 504 and the balance mass 508. The driving force accelerates the moving frame 504 in the desired direction. For the conservation of momentum, the driving force is also applied to the balance mass 508 with equal magnitude in the opposite direction to the desired direction. Typically, the mass of the balance mass 508 is significantly larger than the mass of the moving frame 504.

[0073] In some aspects, the actuator device 510 may comprise a coil (e.g., a wire wound around a ferromagnetic core) and a magnet. In some aspects, the magnet may comprise a material that responds to a magnetic field (e.g., metal, iron, ferrite, etc.). In some aspects, the actuator device 510 may include a movable element 511 or 511' that is attached to the movable frame 504. The actuator device 510 can drive the movable frame 504 by causing the coil to interact with the magnet in order to provide a driving force for driving the movable element 511 or 511'. In some aspects, the movable element 511 (shown in Figure 6A) may include a coil (e.g., coils 626a to 626f shown in Figure 6A) configured to interact with the magnet of the actuator device 510 (e.g., magnet 622 shown in Figure 6A). In some respects, the movable element 511' (shown in Figure 6B) may include a magnet (e.g., magnet 622 shown in Figure 6B) configured to interact with the coils of the actuator device 510 (e.g., coils 626a to 626f shown in Figure 6B).

[0074] In some respects, the actuator device 510 may include an electromagnet configured to generate and regulate a magnetic field. The electromagnet may comprise a coil of wire wound around a metal core (e.g., a ferrite core) (e.g., coils 626a-626f as shown in Figures 6A and 6B). The actuator device 510 can cause the coil to repel and attract a magnet by reversing the direction of the magnetic field. The actuator setup described herein may be represented by other technical terms (e.g., linear actuator). The number and configuration of actuator-related elements are not limited to those shown in Figure 5. Fewer or more actuator-related elements may be used in combination with other configurations.

[0075] In some respects, the actuator device 510 can drive the moving frame 504 using high acceleration. The acceleration can be, for example, about 4-100g, 10-50g, 20-40g, etc. (where g is 9.8 m / s²). 2 It may also be (i.e., it is). High acceleration can increase lithography print production (e.g., increase throughput). Lithography pattern transfer may be performed when the moving frame 504 is in motion (e.g., when it reaches a certain coasting speed). The coasting speed may be, for example, 0.5-10.0 m / s, 1.0-7.0 m / s, 3.0-5.0 m / s, etc. In some aspects, the moving frame 504 may be configured to move with a predetermined amount of kinetic energy based on these coasting speeds. Performing pattern transfer at a constant scanning speed may result in a more accurate transfer of the pattern to be printed, while printing during acceleration may involve greater positional uncertainty.

[0076] 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 the rate of lithography manufacturing. For example, throughput may represent the rate at which lithography manufacturing is completed on a wafer, the rate at which a wafer clears a particular manufacturing step and moves on to the next step, etc. Throughput may also be a performance marker for lithography equipment. A lithography system is desirable to produce as many products as possible in as little time as possible. Lithography manufacturing can involve several complex processes. Each part of the process may involve trade-offs that balance quality (e.g., sub-nanometer precision, high yield) and drawbacks (e.g., slower manufacturing, cost). For example, to increase pattern transfer speed, lithography can implement faster but more accurate substrate and / or mask driving.

[0077] However, implementing faster drive speeds can increase the risk of mechanical damage to the lithography apparatus in the event of an error scenario. Error scenarios can include failures involving actuators, software, temperature, etc. As a result, error scenarios may necessitate shutting down actuators to control material and machine damage. Shutting down actuators exposes the lithography apparatus to the risk of collision events in which the moving stage may collide with the base frame. Therefore, the lithography apparatus may utilize devices to dissipate all the kinetic energy of the moving stage. Dissipating kinetic energy can be achieved by electromotive force braking, conventional mechanical buffers, or both.

[0078] In some respects, Figure 5 illustrates the operation of the components of Stage 500 when an error scenario occurs. When an error scenario occurs, the moving frame 504 may move at a first directional velocity 514. The balance mass 508 is force-coupled to the moving frame 504, which may result in a second directional velocity 516 for the balance mass 508. In some respects, the actuator device 510 may be configured to stop the movement of the moving frame 504 through braking in response to the error scenario in order to prevent collision damage.

[0079] To reduce the first directional velocity 514 of the moving frame 504, one or more actuator devices 510 may be electrically short-circuited. In some aspects, the actuator devices 510 may be selectively short-circuited in real time. Electrically short-circuiting the actuator devices 510 may induce a current in one or more actuator devices 510 because the coils move relative to the magnets.

[0080] Inducing an electric current in the coils can generate a magnetic field in one or more coils that is opposite to the magnetic field from one or more magnets, thereby generating an electromotive braking force 518 in a second direction opposite to the direction of motion of the moving frame 504's first directional velocity 514. The electromotive braking force 518 can generate a reaction force 520 on the balance mass 508 in the first direction opposite to the balance mass 508's second directional velocity 516. The electromotive braking force 518 and the reaction force 520 can reduce the first directional velocity 514 of the moving frame 504 and the second directional velocity 516 of the balance mass 508 before the moving frame 504 collides with the mechanical buffer 512a and before the balance mass 508 collides with the mechanical buffer 512b. In this way, the electromotive braking force 518 can reduce the kinetic energy of the moving frame 504.

[0081] In some aspects, the mechanical buffer 512a may be a shock absorber, damper, spring, or a combination thereof, used to absorb the remaining kinetic energy of the moving frame 504 after one or more actuator devices 510 have completed their braking actions in response to an error scenario. In some aspects, the mechanical buffer 512b may be a shock absorber, damper, spring, or a combination thereof, used to absorb the remaining kinetic energy of the balance mass 508 after one or more actuator devices 510 have completed their braking actions in response to an error scenario. In some aspects, the mechanical buffers 512a and 512b may be shock absorbers, dampers, springs, or a combination thereof.

[0082] In some respects, electromotive force braking can reduce the braking distance of the moving frame 504. Thus, electromotive force braking can enable a reduction in the size of the mechanical buffers 512a and 512b for efficient use of the limited volume in the lithography apparatus.

[0083] In some respects, the moving frame 504 can operate in a vacuum environment. Mechanical buffers that use dampers in a vacuum environment risk leaking hydraulic fluid and contaminating the environment. As a result, such dampers should not be used in a vacuum environment. For this reason, the electromotive braking force 518 can provide damping in a vacuum environment without the drawbacks of mechanical buffer dampers.

[0084] In some aspects, electromotive force braking may be used to reduce the speed of the wafer stage. In some aspects, the moving frame 504 may be a wafer stage (e.g., a WT shown in Figures 1A and 1B). In some aspects, the moving frame 504 (e.g., a WT shown in Figures 1A and 1B) may include one or more actuator devices 510 configured to be electrically short-circuited to generate an electromotive force 518 opposite to a first directional velocity 514 of the moving frame 504 (e.g., a WT shown in Figures 1A and 1B) on a linear axis, in order to reduce the braking distance of the moving frame 504 (e.g., a WT shown in Figures 1A and 1B) in order to prevent collision damage.

[0085] Figures 6A and 6B show schematic cross-sectional views of actuator devices 510 and 510' relating to several aspects, respectively. The descriptions in Figures 6A and 6B are understood to also represent the aspects of Figure 5 when discussing 5xx elements. Although the actuator devices 510 and 510' are shown in Figures 6A and 6B as standalone devices and / or systems, aspects of this disclosure may be used in conjunction with other devices, systems, and / or methods such as (but not limited to) lithography apparatus LA, support structure MT, substrate table WT, etc. In some aspects, the actuator device 510 or 510' may be part of a lithography apparatus, e.g., lithography apparatus LA. In some aspects, the actuator device 510 or 510' may be part of a support structure, e.g., support structure MT for patterning device MA. In some respects, the actuator device 510 or 510' may include a magnet 622, a back iron plate 624, a movable element 511 or 511', coils 626a to 626f, and a controller 628.

[0086] In some aspects, the actuator device 510 or 510' may be a linear actuator configured to provide driving force along a single axis, for example, the Y-axis. Multiple linear actuators may be provided to provide driving force along multiple axes. In some aspects, the actuator device 510 or 510' may be a planar actuator for providing driving force along multiple axes. For example, a planar actuator may be provided to drive a substrate table WT in six degrees of freedom.

[0087] In some aspects, the actuator device 510 or 510' may be an electromagnetic actuator comprising at least one coil and at least one magnet. The actuator device 510 or 510' may be configured to drive at least one coil relative to at least one magnet by applying current to at least one coil. In some aspects, the actuator device 510 may be a moving coil type actuator having at least one coil coupled to a moving frame 504, wherein one or more coils move at high speed in the vicinity of one or more stationary magnets. In some aspects, the actuator device 510' may be a moving magnet type actuator having at least one magnet coupled to a moving frame 504, wherein one or more magnets move at high speed in the vicinity of one or more stationary coils. In some aspects, the actuator device 510 or 510' may be a voice coil actuator, a reluctance actuator, a Lorentz actuator, a piezo actuator, or any other suitable actuator.

[0088] In some aspects, as shown in Figure 6A, the actuator device 510 may include arrays of multiple permanent magnets 622 arranged in two parallel planes extending in the Y direction and in the X direction perpendicular to the Y and Z directions. Each array of permanent magnets 622 forming one of the two parallel planes may be supported by its respective back iron plate 624. The back iron plate 624 can support the magnets 622 and keep the magnetic field generated by the magnets 622 within the actuator device 510, thereby increasing the efficiency of the actuator device 510. In some aspects, the back iron plate 624 may be mounted on a balance mass 508 as shown in Figure 5.

[0089] In some aspects, as shown in Figure 6A, a movable element 511 that is movable relative to the magnet 622 may be positioned between two faces of the permanent magnet 622. In some aspects, the movable element 511 may be provided with a coil arrangement comprising a plurality of coils 626a to 626f, forming a multiphase coil arrangement. Each coil 626a to 626f may be arranged so that the current flowing through each coil 626a to 626f interacts with the magnetic field generated by the permanent magnet 622 in order to generate a Lorentz force in the principal direction (here, the Y direction). The coil arrangement in the movable element 511 may include a first coil portion formed by coils 626a to 626c and a second coil portion formed by coils 626d to 626f. In some aspects, as shown in Figure 6A, the first coil portion formed by coils 626a to 626c and the second coil portion formed by coils 626d to 626f may be provided with substantially similar currents to generate substantially similar Lorentz forces in the principal direction. In some aspects, the movable element 511 may be attached to the movable frame 504 shown in Figure 5 such that the generated Lorentz force drives the movable frame 504 along the longitudinal axis (e.g., the Y-axis).

[0090] In some aspects, the coil arrangement may be a three-phase coil arrangement, where coils 626a and 626d form the first phase, coils 626b and 626e form the second phase, and coils 626c and 626f form the third phase. In some aspects, the AC current flowing through the first to third phases may be a sine wave with a 120-degree phase shift between each phase. This aspect is merely one non-limiting example, and other phase configurations may be implemented.

[0091] In some aspects, a controller 628 coupled to the actuator device 510 may be configured to control the movement (e.g., translation) of the movable element 511 along the longitudinal axis (e.g., Y-axis) of the stage 500. In some aspects, the controller 628 may be coupled (e.g., electronically) to coils 626a-626f. In some aspects, the controller 628 may be able to adjust the magnitude and direction of the current flowing through coils 626a-626f to adjust the magnetic field strength and magnetic force. In some aspects, the controller 628 may be able to selectively short its corresponding actuator device 510 to redirect the current flowing through coils 626a-626f. For example, the controller 628 may short the actuator device 510 to induce an opposing current resulting from the relative motion between coils 626a-626f and magnet 622, thereby generating an electromotive braking force 518.

[0092] In some aspects, the moving frame 504, as shown in Figure 5, may be moving at a first-direction velocity 514 during an error scenario. To prevent mechanical damage caused by a collision, the controller 628 can selectively short its corresponding actuator device 510 to redirect the current flowing through coils 626a-626f. In some aspects, the controller 628 can short the actuator device 510 to induce an opposing current flowing through coils 626a-626f, brought about by the relative motion between the magnet 622 and coils 626a-626f. The induced opposing current flowing through coils 626a-626f can generate an electromotive braking force 518 in a second direction opposite to the first-direction velocity 514 of the moving frame 504, as shown in Figure 5. In some aspects, the electromotive braking force 518 can reduce the first-direction velocity 514 and reduce the kinetic energy of the moving frame 504, as shown in Figure 5. In some respects, the controller 628 may include a capacitor configured to charge one or more actuators 510 with energy recovered from the electromotive braking force 518.

[0093] In some respects, the electromotive braking force 518 can be determined by the following equation:

number

[0094] While the side view shown in Figure 6A is a moving coil configuration, it will be apparent to those skilled in the art that the actuator may also be a moving magnet actuator (e.g., actuator device 510') as shown in the side view of Figure 6B. In some aspects, multiple magnets 622 may be attached to each other to form a movable element 511' that can move between two parallel planes of coils 626a to 626f. In some aspects, a back iron plate 624 may be attached to the balance mass 508 shown in Figure 5. In some aspects, the movable element 511' may be attached to the moving frame 504 shown in Figure 5 so that the resulting Lorentz force drives the moving frame 504 along the longitudinal axis (e.g., the Y-axis). In some aspects, the moving magnet configuration of actuator device 510' may include a coil arrangement with multiple coils arranged in two parallel planes (a first coil portion formed by coils 626a to 626c and a second coil portion formed by coils 626d to 626f). In some aspects, the actuator device 510' may also be a multiphase coil arrangement, where each phase comprises two coils (coils 626a and 626d may form the first phase, coils 626b and 626e may form the second phase, and coils 626c and 626f may form the third phase). In some aspects, a controller 628 coupled to the actuator device 510' may be configured to control the movement (e.g., translation) of the movable element 511' along the longitudinal axis (e.g., Y-axis) of the stage 500. In some aspects, the controller 628 may generate an electromotive braking force 518 resulting from the relative motion of the magnet 622 and coils 626a-626f, as described with respect to Figure 6A.

[0095] Figures 7A and 7B show a mechanical buffer relating to several aspects. The descriptions in Figures 7A and 7B are understood to also represent the aspects of Figure 5 when discussing the 5xx elements. For example, in Figures 7A and 7B, the mechanical buffer 512 or 512' may be the aspect of the mechanical buffer 512a shown in Figure 5, or the aspect of the mechanical buffer 512b shown in Figure 5. In Figure 7A, the mechanical buffer 512 may include the damper 730, spring 732, guide pin 734, impact site 736, and mounting site 738. In Figure 7B, the mechanical buffer 512' may include the spring 732, guide pin 734, impact site 736, and mounting site 738.

[0096] In some aspects, to prevent collisions with fast-moving objects (for example, in the event of an error scenario in a lithography apparatus), a mechanical buffer 512 or 512' may be attached to the base frame 506 shown in Figure 5 at the mounting site 738. It is undesirable to allow the moving frame 504 or balance mass 508 to collide with the base frame 506. Collisions can damage the structure and / or contaminate the clean lithography environment by releasing contaminating particles that can adhere to the reticle and / or wafer. For this reason, the moving frame 504, balance mass 508, and base frame 506 may be protected by a mechanical buffer 512 or 512'. In some aspects, the mechanical buffer 512 or 512' may be attached to the base frame 506 at the mounting site 738 using any suitable method (e.g., adhesive, bolts, nails, clamps, etc.). In some aspects, a mechanical buffer 512 or 512' may be provided to maintain a non-zero gap distance between the moving frame 504 and the base frame 506. In some aspects, a mechanical buffer 512 or 512' may be provided to maintain a non-zero gap distance between the balance mass 508 and the base frame 506.

[0097] In some respects, a mechanical buffer may incorporate any retractable structure (e.g., a spring, flexure, hydraulic pressure, etc.).

[0098] In some aspects, guide pins 734 may be positioned within the side spring 732 to prevent undesirable deformation during contraction.

[0099] In one exemplary aspect, the mechanical buffer 512 may include a damper 730 configured to absorb kinetic energy from the moving frame 504 or balance mass 508, and a spring 732 configured to push the moving frame 504 or balance mass 508 in the opposite direction to the direction of motion.

[0100] In another exemplary aspect, the mechanical buffer 512' may include a spring 732 configured to push the moving frame 504 or balance mass 508 in the opposite direction to the direction of motion.

[0101] During a collision event, the collision site 736 of the mechanical buffer 512 or 512' may come into contact with the surface of the moving frame 504 or the balance mass 508. In some respects, the collision site 736 may have a shape and material that does not cause mechanical damage to the moving frame 504 or the balance mass 508.

[0102] In some respects, the damper 730 may not function properly in a vacuum environment, and any leaking hydraulic fluid could contaminate the environment, so the mechanical buffer 512 can operate in an environment with air.

[0103] In some respects, since the spring 732 does not pose a risk of environmental contamination, the mechanical buffer 512' can operate in any environment (e.g., air, vacuum, etc.). Thus, the electromotive braking force 518 shown in Figure 5 is advantageous in lithography equipment because it can provide a damping function in any environment (e.g., air, vacuum, etc.).

[0104] Figure 8 shows the braking method 800 in several aspects. In some aspects, in step 802, a current may be applied to one or more actuator coils (e.g., coils 626a to 626f shown in Figures 6A and 6B) so as to interact with a magnetic field from one or more magnets (e.g., magnet 622 shown in Figures 6A and 6B) in the vicinity of one or more actuator coils (e.g., coils 626a to 626f shown in Figures 6A and 6B).

[0105] In some respects, step 804 may generate a force to drive the moving frame in the lithography apparatus (e.g., the moving frame 504 shown in Figure 5) in a first direction (e.g., the first direction velocity 514 shown in Figure 5).

[0106] In some aspects, in step 806, one or more actuator coils may be shorted during the movement of the moving frame in response to an error scenario in order to prevent collision damage. In some aspects, one or more actuator coils may be configured to be selectively shorted in real time.

[0107] In some respects, in step 808, a current may be induced in one or more actuator coils due to the magnetic field from one or more magnets.

[0108] In some respects, in step 810, in order to generate an electromotive braking force (e.g., electromotive braking force 518) in a second direction opposite to the first direction of movement of the moving frame, one or more actuator coils may generate a magnetic field opposite to the magnetic field from one or more magnets.

[0109] In some aspects, in step 812, the speed of the moving frame may be reduced before it collides with one or more mechanical buffers (e.g., mechanical buffer 512 or 512'). In some aspects, the speed of one or more actuator coils may be reduced to reduce the speed of the moving frame in any environment. In some aspects, the speed of one or more magnets may be reduced to reduce the speed of the moving frame in any environment.

[0110] The method steps in Figure 8 can be performed in any possible order, and not all steps need to be performed. Furthermore, the method steps in Figure 8 described above are non-exclusive and merely reflect an example of method steps. In other words, further method steps and functions can be conceivable based on the aspects described with reference to Figures 1A-7B.

[0111] Various embodiments of this apparatus, system, and method are disclosed in the following list of numbered items. Item 1: A lighting system configured to generate a beam of radiation, A patterning system comprising a reticle and configured to impart a pattern to the beam, A projection system configured to project a patterned beam onto a substrate, A moving frame configured to move with a predetermined amount of kinetic energy, One or more balance masses in the vicinity of the moving frame are configured to absorb the reaction force acted upon the moving frame, One or more actuators configured to drive the moving frame and stop the movement of the moving frame through braking according to an error scenario in order to prevent collision damage, the actuators configured to be electrically short-circuited to generate an electromotive braking force opposite to the direction of movement of the moving frame in order to reduce the kinetic energy of the moving frame and reduce the braking distance of the moving frame, The one or more actuators are configured to absorb the remaining kinetic energy of the moving frame after completing their braking actions in response to the error scenario, and the one or more mechanical buffers are configured to do so. A reticle stage equipped with, A lithography apparatus equipped with [a specific feature]. Item 2: The lithography apparatus according to item 1, wherein one or more actuators are configured to be selectively shorted in real time. Item 3: The lithography apparatus according to item 1, wherein the one or more mechanical buffers comprise shock absorbers, dampers, springs, or a combination thereof, configured to operate in an air-filled environment. Item 4: The lithography apparatus according to item 3, wherein the one or more actuators comprises one or more coils moving at high speed in the vicinity of one or more stationary magnets. Item 5: The lithography apparatus according to item 1, wherein the one or more mechanical buffers are equipped with springs such that only the electromotive braking force provides damping in a vacuum environment. Item 6: The lithography apparatus according to item 5, wherein the one or more actuators comprises one or more magnets moving at high speed in the vicinity of one or more stationary coils. Item 7: The lithography apparatus according to item 1, further comprising a capacitor configured to charge one or more actuators with energy recovered from the electromotive braking force. Item 8: The lithography apparatus according to item 1, further comprising a wafer stage having one or more actuators configured to be electrically short-circuited to generate an electromotive braking force on a linear axis opposite to the direction of motion of the wafer stage in order to reduce the braking distance of the wafer stage in order to prevent collision damage. Item 9: A moving frame configured to move with a predetermined amount of kinetic energy, One or more balance masses in the vicinity of the moving frame are configured to absorb the reaction force acted upon the moving frame, One or more actuators configured to drive the moving frame and stop the movement of the moving frame through braking according to an error scenario in order to prevent collision damage, the actuators configured to be electrically short-circuited to generate an electromotive braking force opposite to the direction of movement of the moving frame in order to reduce the kinetic energy of the moving frame and reduce the braking distance of the moving frame, The one or more actuators are configured to absorb the remaining kinetic energy of the moving frame after completing their braking actions in response to the error scenario, and the one or more mechanical buffers are configured to do so. A braking system equipped with [a specific feature]. Item 10: The braking system according to item 9, wherein the one or more actuators are configured to be selectively shorted in real time. Item 11: The braking system according to item 9, wherein the one or more mechanical buffers are shock absorbers, dampers, springs, or combinations thereof, configured to operate in an air-filled environment. Item 12: The braking system according to item 11, wherein the one or more actuators comprises one or more coils moving at high speed in the vicinity of one or more stationary magnets. Item 13: The braking system according to item 9, wherein the one or more mechanical buffers are equipped with springs such that only the electromotive braking force provides damping in a vacuum environment. Item 14: The braking system according to item 13, wherein the one or more actuators comprise one or more magnets moving at high speed in the vicinity of one or more stationary coils. Item 15: The braking system according to item 9, further comprising a capacitor configured to charge one or more actuators with energy recovered from the electromotive braking force. Item 16: The braking system according to item 9, further comprising a wafer stage having one or more actuators configured to be electrically short-circuited to generate an electromotive braking force on a linear axis opposite to the direction of motion of the wafer stage in order to reduce the braking distance of the wafer stage in order to prevent collision damage. Item 17: Applying a current to one or more actuator coils so as to interact with a magnetic field from one or more magnets in the vicinity of one or more actuator coils, To generate a force to drive the moving frame in a lithography apparatus in a first direction, To prevent collision damage, depending on the error scenario, one or more actuator coils are shorted during the movement of the moving frame. The magnetic field from the one or more magnets induces a current in the one or more actuator coils, In order to generate an electromotive braking force in a second direction opposite to the first direction of movement of the moving frame, the one or more actuator coils generate a magnetic field opposite to the magnetic field from the one or more magnets, The speed of the moving frame is reduced before the moving frame collides with one or more mechanical buffers. A braking method that includes [a specific feature / feature]. Item 18: The braking method according to item 17, wherein the one or more actuator coils are configured to be selectively shorted in real time. Item 19: The braking method according to item 17, wherein reducing the speed of the moving frame comprises reducing the speed of one or more actuator coils in any environment. Item 20: The braking method according to item 17, comprising reducing the speed of the moving frame to reduce the speed of one or more magnets in any environment.

[0112] The terms “radiation,” “beam,” “light,” and “illumination” may be used here to describe one or more types of electromagnetic radiation (e.g., ultraviolet (UV) radiation (e.g., with wavelengths λ of 365, 248, 193, 157, or 126 nm), extreme ultraviolet (EUV or soft X-ray) radiation (e.g., with wavelengths in the 5-100 nm range, such as 13.5 nm), or hard X-rays operating in the range shorter than 5 nm, and particle beams such as ion beams or electron beams). Generally, radiation with wavelengths between approximately 400 and 700 nm is interpreted as visible radiation, and radiation with wavelengths between approximately 780 and 3000 nm (or above) is interpreted as IR radiation. UV refers to radiation with wavelengths of approximately 100-400 nm. In lithography, the term "UV" also refers to wavelengths that can be produced by mercury discharge lamps (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 with wavelengths of approximately 100–200 nm. Deep UV (DUV) generally refers to radiation with wavelengths ranging from 126 nm to 428 nm, and in some respects, excimer lasers can produce DUV radiation used in lithography equipment. For example, radiation with wavelengths in the 5–20 nm range should be understood as referring to radiation with a specific wavelength band that is at least partially within the 5–20 nm range.

[0113] While some aspects of this disclosure are described in the context of lithography equipment in the manufacture of ICs, it should be understood that the lithography equipment described herein may be used in other applications (e.g., the manufacture of integrated optical systems, guidance and detection patterns for magnetic domain memory, flat panel displays, LCDs, thin-film magnetic heads, etc.). In the context of such alternative applications, those skilled in the art will understand that the terms “wafer” or “die” as used herein may be interpreted as specific examples of the more general terms “substrate” or “target portion,” respectively. The substrate may be processed before or after exposure, for example, in a track unit (typically a tool that applies a layer of resist to the substrate and develops the exposed resist) and / or a measurement unit. Where applicable, the aspects disclosed herein may be applied to such other substrate processing tools. Furthermore, for example, to form a multi-layer IC, the substrate may be processed multiple times, and the term “substrate” as used herein may refer to a substrate that already contains multiple processed layers.

[0114] Furthermore, while some aspects of this disclosure are described in the context of optical lithography, it should be understood that these aspects are not limited to optical lithography. For example, in imprint lithography, topography in a patterning device defines the pattern to be produced on a substrate. The topography of the patterning device may be pressed into a layer of resist supplied to the substrate, and the resist is cured thereon by applying electromagnetic radiation, heat, pressure, or a combination thereof. After the resist has cured, the patterning device is driven out of the resist, leaving a pattern within the resist.

[0115] The expressions and terms herein are intended for non-exclusive purposes, and it is understood that the terms and expressions herein should be interpreted by those skilled in the art under the teachings herein.

[0116] This disclosure was described above using functional configuration blocks that illustrate the implementation of specific functions and their relationships. The boundaries of these functional configuration blocks are arbitrarily defined herein for the sake of descriptive convenience. Other boundaries may be defined, insofar as specific functions and their relationships are adequately realized. The above descriptions of specific aspects fully reveal the essence of this disclosure so that others, by applying knowledge in the art, can easily modify and / or adapt such specific aspects to various uses without excessive experimentation or deviation from the concepts of this disclosure. Accordingly, such adaptations and modifications are intended to be within the meaning and scope of equivalents of the disclosed aspects, based on the teachings and suggestions presented herein.

[0117] It is understood that the section “Modes for Carrying Out the Invention,” rather than the sections “Summary of the Invention” and “Abstract,” is intended to be used to interpret the claims. The sections “Summary of the Invention” and “Abstract” may present one or more aspects of the present disclosure as conceived by the inventor, but are not necessarily limited to all aspects, and are not intended to limit the present disclosure and the attached claims in any way. The breadth and scope of the subject matter protected should not be limited by any of the aforementioned aspects, but should be determined in accordance with the following claims and their equivalents.

Claims

1. A lighting system configured to generate a beam of radiation, A patterning system comprising a reticle and configured to impart a pattern to the beam, A projection system configured to project a patterned beam onto a substrate, A moving frame configured to move with a predetermined amount of kinetic energy, One or more balance masses in the vicinity of the moving frame are configured to absorb the reaction force acted upon the moving frame, One or more actuators configured to drive the moving frame and stop the movement of the moving frame through braking according to an error scenario in order to prevent collision damage, the actuators configured to be electrically short-circuited to generate an electromotive braking force opposite to the direction of movement of the moving frame in order to reduce the kinetic energy of the moving frame and reduce the braking distance of the moving frame, The one or more actuators are configured to absorb the remaining kinetic energy of the moving frame after completing their braking actions in response to the error scenario, and the one or more mechanical buffers are configured to do so. A reticle stage equipped with, A lithography apparatus equipped with [a specific feature].

2. The lithography apparatus according to claim 1, wherein the one or more actuators are configured to be selectively shorted in real time.

3. The one or more mechanical buffers comprising a shock absorber, damper, spring, or a combination thereof, configured to operate in an environment with air, The one or more actuators comprises one or more coils that move at high speed in the vicinity of one or more stationary magnets. The lithography apparatus according to claim 1.

4. The one or more mechanical buffers are equipped with springs such that only the electromotive braking force provides damping in a vacuum environment. The one or more actuators include one or more magnets that move at high speed in the vicinity of one or more stationary coils. The lithography apparatus according to claim 1.

5. The lithography apparatus according to claim 1, further comprising a capacitor configured to charge one or more actuators with energy recovered from the electromotive braking force.

6. The lithography apparatus according to claim 1, further comprising a wafer stage having one or more actuators configured to be electrically short-circuited to generate an electromotive braking force on a linear axis opposite to the direction of motion of the wafer stage in order to reduce the braking distance of the wafer stage in order to prevent collision damage.

7. A moving frame configured to move with a predetermined amount of kinetic energy, One or more balance masses in the vicinity of the moving frame are configured to absorb the reaction force acted upon the moving frame, One or more actuators configured to drive the moving frame and stop the movement of the moving frame through braking according to an error scenario in order to prevent collision damage, the actuators configured to be electrically short-circuited to generate an electromotive braking force opposite to the direction of movement of the moving frame in order to reduce the kinetic energy of the moving frame and reduce the braking distance of the moving frame, The one or more actuators are configured to absorb the remaining kinetic energy of the moving frame after completing their braking actions in response to the error scenario, and the one or more mechanical buffers are configured to do so. A braking system equipped with [a specific feature].

8. The braking system according to claim 7, wherein the one or more actuators are configured to be selectively shorted in real time.

9. The one or more mechanical buffers comprising a shock absorber, damper, spring, or a combination thereof, configured to operate in an environment with air, The one or more actuators comprises one or more coils that move at high speed in the vicinity of one or more stationary magnets. The braking system according to claim 7.

10. The one or more mechanical buffers are equipped with springs such that only the electromotive braking force provides damping in a vacuum environment. The one or more actuators include one or more magnets that move at high speed in the vicinity of one or more stationary coils. The braking system according to claim 7.

11. The braking system according to claim 7, further comprising a capacitor configured to charge one or more actuators with energy recovered from the electromotive braking force.

12. The braking system according to claim 7, further comprising a wafer stage having one or more actuators configured to be electrically short-circuited to generate an electromotive braking force on a linear axis opposite to the direction of motion of the wafer stage in order to reduce the braking distance of the wafer stage in order to prevent collision damage.

13. Applying a current to one or more actuator coils so as to interact with a magnetic field from one or more magnets in the vicinity of one or more actuator coils, To generate a force for driving the moving frame in a lithography apparatus in a first direction, To prevent collision damage, depending on the error scenario, one or more actuator coils are shorted during the movement of the moving frame. The magnetic field from the one or more magnets induces a current in the one or more actuator coils, In order to generate an electromotive braking force in a second direction opposite to the first direction of movement of the moving frame, the one or more actuator coils generate a magnetic field opposite to the magnetic field from the one or more magnets, The speed of the moving frame is reduced before the moving frame collides with one or more mechanical buffers. A braking method that includes [a specific feature / feature].

14. The braking method according to claim 13, wherein the one or more actuator coils are configured to be selectively shorted in real time.

15. The braking method according to claim 13, wherein reducing the speed of the moving frame comprises reducing the speed of one or more actuator coils in any environment, or reducing the speed of one or more magnets in any environment.

Images