Substrate support, substrate table and method - Patents.com

Abstract

A substrate support for supporting a substrate in a lithographic apparatus comprises: a first support configured to support the substrate; a body separated from the first support and configured to support the first support, the body comprising a thermal conditioner configured to thermally condition the body, the support and / or the substrate; and an extraction body surrounding the body and the support, the extraction body comprising a first extraction channel configured to extract fluid from near a peripheral edge of the substrate.

Description

[Technical field]

[0001] [CROSS REFERENCE TO RELATED APPLICATIONS] This application claims priority to European Application No. 20158919.9, filed February 24, 2020, and European Application No. 20163571.1, filed March 17, 2020, which are incorporated by reference in their entireties.

[0002] [Technical field] The present invention relates to a substrate support for supporting a substrate in a lithographic apparatus, a substrate table, a method for supporting a substrate and a device manufacturing method. [Background technology]

[0003] A lithographic apparatus is a machine that is configured to apply a desired pattern onto a substrate. Lithographic apparatus may be used, for example, in the manufacture of integrated circuits (ICs). A lithographic apparatus may, for example, project a pattern (often also referred to as a "design layout" or "design") from a patterning device (e.g. mask) onto a layer of radiation-sensitive material (resist) provided on a substrate (e.g. wafer). Known lithographic apparatus include so-called steppers, in which each target portion is irradiated by exposing the entire pattern onto the target portion in one go, and so-called scanners, in which each target portion is irradiated by scanning the pattern through a radiation beam in a predetermined direction (the "scan" direction) while simultaneously scanning the substrate parallel or non-parallel to this direction.

[0004] As semiconductor manufacturing processes continue to improve, the dimensions of circuit elements are continually reduced while the amount of functional elements such as transistors per device has steadily increased over the past few decades, following a trend commonly referred to as "Moore's Law". The semiconductor industry pursues technologies that allow for the creation of smaller and smaller features to keep up with Moore's Law. To project a pattern onto a substrate, a lithographic apparatus may use electromagnetic radiation. The wavelength of this radiation determines the minimum size of features that can be patterned on the substrate. Typical wavelengths currently in use are 365 nm (i-line), 248 nm, 193 nm, and 13.5 nm.

[0005] Further improvements in the resolution of smaller features may be realized by providing an immersion fluid, such as water, having a relatively high refractive index, onto the substrate during exposure. The effect of the immersion fluid is to allow imaging of smaller features, since the exposure radiation in the fluid has a shorter wavelength than in a gas. The effect of the immersion fluid is also to increase the effective numerical aperture (NA) of the system, which also increases the depth of focus. Summary of the Invention [Problem to be solved by the invention]

[0006] The immersion fluid may be confined to a localized area between the projection system of the lithographic apparatus and the substrate by a fluid handling structure. Fast relative movement between the substrate and the confined immersion liquid may cause leakage of the immersion fluid from the localized area. Such leakage is undesirable and may lead to defects on the substrate. This limits the speed at which the substrate can be stepped or scanned relative to the projection system. This limits the throughput of the lithographic apparatus.

[0007] During the semiconductor manufacturing process, a substrate is supported on a substrate support. Over time, the substrate support wears out and needs to be replaced. It is an object of the present invention to provide a substrate support that is cheaper to maintain and reduces the amount of downtime required for servicing when worn out. [Means for solving the problem]

[0008] According to the invention there is provided a substrate support for supporting a substrate in a lithographic apparatus comprising: a first support configured to support a substrate, a body separate from the first support and configured to support the first support, the body comprising a thermal conditioner configured to thermally condition the body, the support and / or the substrate, and an extraction body surrounding the body and the support, the extraction body comprising a first extraction channel configured to extract fluid from near a peripheral edge of the substrate.

[0009] According to the invention there is also provided a substrate table comprising a substrate stage and a substrate support.

[0010] According to the invention there is also provided a method for supporting a substrate on a substrate support in a lithographic apparatus, the method comprising supporting the substrate on a first support of the substrate support, supporting the first support on a body separate from the first support, thermally conditioning the body, the support and / or the substrate with a thermal conditioner of the body, and extracting fluid from near a periphery of the substrate through a first extraction channel of an extraction body surrounding the body and the support.

[0011] According to the invention there is also provided a method for replacing a first support of a substrate support for supporting a substrate in a lithographic apparatus, the method comprising: connecting a carrier plate to the first support such that the carrier plate covers pinholes passing through the first support in a thickness direction of the first support, extending a number of pins through each pinhole such that the pins support the carrier plate on their ends and the pins pass through a body of the substrate support below the first support, and controlling movement of the pins to lower or raise the first support onto or from the body.

[0012] According to the invention there is also provided a device manufacturing method using a lithographic apparatus comprising projecting a beam patterned by a patterning device onto a substrate while the substrate is supported by a substrate support, and performing a method for supporting the substrate in the lithographic apparatus or for replacing a first support of the substrate support for supporting the substrate in the lithographic apparatus.

[0013] Further embodiments, features, and advantages of the present invention, as well as the structure and operation of the various embodiments, features, and advantages of the present invention, are described in detail below with reference to the accompanying drawings. [Brief description of the drawings]

[0014] Embodiments of the invention will now be described, by way of example only, with reference to the following accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts: FIG. 1 shows a schematic diagram of a lithographic apparatus. Figures 2 and 3 show, in cross-section, two different versions of a fluid handling system for use in a lithographic projection apparatus. FIG. 4 shows parts of a lithographic apparatus. FIG. 5 shows a substrate support according to an embodiment of the invention. FIG. 6 shows a substrate support according to a comparative example. 7 to 11 show different versions of a substrate support according to the invention. 12 and 13 show different versions of the height adjustment mechanism for an embodiment of the invention. FIG. 14 is a schematic cross-sectional view of a carrier plate connected to a first support according to an embodiment of the invention. FIG. 15 is a schematic cross-sectional view of the assembly shown in FIG. 14 being lowered onto a body according to an embodiment of the invention. FIG. 16 is a schematic cross-sectional view of the carrier plate being separated from the first support shown in FIGS. FIG. 17 is a schematic cross-sectional view of a carrier plate connected to a first support according to an embodiment of the invention. FIG. 18 is a schematic cross-sectional view of a carrier plate connected to a first support according to an embodiment of the invention. FIG. 19 is a schematic cross-sectional view of a carrier plate connected to a first support according to an embodiment of the invention. FIG. 20 is a schematic cross-sectional view of a mechanism for connecting a carrier plate to a first support according to an embodiment of the invention. FIG. 21 is a schematic cross-sectional view midway through the process of separating the carrier plate shown in FIG. 20 from the first support. 22 is a schematic cross-sectional view of the carrier plate being separated from the first support shown in FIG. 20. FIG. FIG. 23 is a schematic cross-sectional view of a mechanism for connecting a carrier plate to a first support according to an embodiment of the invention. FIG. 24 is a schematic cross-sectional view midway through the process of separating the carrier plate shown in FIG. 23 from the first support. FIG. 25 is a schematic cross-sectional view of the carrier plate being separated from the first support shown in FIG. FIG. 26 is a schematic plan view of a first support according to an embodiment of the invention. FIG. 27 is a schematic plan view of a first support according to an embodiment of the invention being gripped for handling. FIG. 28 is a schematic plan view of a first support according to an embodiment of the invention being gripped for handling.

[0015] Features shown in the figures are not necessarily drawn to scale and are not limited to the size and / or configuration shown. The figures are understood to include optional features that are not essential to the invention. Moreover, not all features of a device are shown in each figure, and the figures may show only some of the components that are relevant to describing a particular feature. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] In this document, the terms "radiation" and "beam" are used to encompass all types of electromagnetic radiation, including ultraviolet radiation (eg, having wavelengths of 365, 248, 193, 157 or 126 nm).

[0017] The terms "reticle," "mask," or "patterning device" as used in this text may be broadly interpreted to refer to a general patterning device that may be used to impart an incident radiation beam with a patterned cross-section that corresponds to the pattern to be created in a target portion of a substrate. The term "light valve" may also be used in this context. Besides the classic mask (transmissive or reflective; binary, phase-shifting, hybrid, etc.), examples of other such patterning devices include programmable mirror arrays and programmable LCD arrays.

[0018] 1 illustrates a lithographic apparatus comprising an illumination system (also denoted illuminator) IL configured to condition a radiation beam B (e.g. UV or DUV radiation), a mask support (e.g. mask table) MT configured to support a patterning device (e.g. mask) MA and connected to a first positioner PM configured to accurately position the patterning device MA according to certain parameters, a substrate support (e.g. substrate table) WT configured to hold a substrate (e.g. resist-coated wafer) W and connected to a second positioner PW configured to accurately position the substrate support WT according to certain parameters, and a projection system (e.g. refractive projection lens system) PS configured to project a pattern formed in the radiation beam B by the patterning device MA onto a target portion C (e.g. comprising one or more dies) of the substrate W.

[0019] In operation, the illumination system IL receives a radiation beam B from the radiation source SO, for example via the beam delivery system BD. The illumination system IL may include various types of optical components, or any combination thereof, such as refractive, reflective, magnetic, electromagnetic, electrostatic and / or other types of optical components, for directing, shaping and / or controlling the radiation. The illuminator IL may be used to condition the radiation beam B such that it has a desired spatial and angular intensity distribution in its cross-section at the plane of the patterning device MA.

[0020] The term "projection system" PS as used herein should be interpreted broadly to encompass various types of projection systems including refractive, reflective, catadioptric, anamorphic, magnetic, electromagnetic and / or electrostatic optical systems, or any combination thereof, appropriate for the exposure radiation being used, and / or other factors such as the use of an immersion liquid or vacuum. Use of the term "projection lens" herein may be interpreted as synonymous with the more general term "projection system" PS.

[0021] The lithographic apparatus is of a type (also referred to as immersion lithography) in which at least part of the substrate W may be covered by an immersion liquid, such as water, having a relatively high refractive index, to fill an immersion space 11 between the projection system PS and the substrate W. More information about immersion techniques is given in US 6,952,253, which is incorporated herein by reference.

[0022] The lithographic apparatus may be of a type having two or more substrate supports WT (also referred to as "dual stage"). In such a "multi-stage" apparatus, the substrate supports WT may be used in parallel and / or preparation steps for a subsequent exposure of a substrate W may be performed on a substrate W located on one substrate support WT while another substrate W on the other substrate support WT is being used to expose a pattern onto another substrate W.

[0023] In addition to the substrate support WT, the lithographic apparatus may comprise a measurement stage (not shown). The measurement stage is provided to hold a sensor and / or a cleaning device. The sensor may be provided to measure a property of the projection system PS or a property of the radiation beam B. The measurement stage may hold a number of sensors. The cleaning device may be provided to clean parts of the lithographic apparatus, for example parts of the projection system PS or parts of a system for providing immersion liquid. The measurement stage may move underneath the projection system PS when the substrate support WT is spaced apart from the projection system PS.

[0024] In operation, the radiation beam B is incident on a patterning device, such as a mask MA, which is held on a mask support MT, and is patterned by a pattern (design layout) present on the patterning device MA. After the mask MA, the radiation beam B passes through a projection system PS which focuses the beam onto a target portion C of a substrate W. By means of the second positioner PW and the position measurement system IF, the substrate support WT may be accurately driven, for example to position different target portions C at focusing and alignment positions in the path of the radiation beam B. Similarly, the first positioner PM and suitable other position sensors (not explicitly shown in Figure 1) may be used to accurately position the patterning device MA with respect to the path of the radiation beam B. The patterning device MA and substrate W may be aligned using mask alignment marks M1, M2 and substrate alignment marks P1, P2. Although the illustrated substrate alignment marks P1, P2 occupy dedicated target portions, they may also be located in spaces between the target portions. The substrate alignment marks P1, P2 located between the target portions C are known as scribe-lane alignment marks.

[0025] To clarify the invention, a Cartesian coordinate system is used. The Cartesian coordinate system has three axes, namely, x-axis, y-axis and z-axis. Each of the three axes is orthogonal to the other two. Rotation about the x-axis is denoted as Rx rotation. Rotation about the y-axis is denoted as Ry rotation. Rotation about the z-axis is denoted as Rz rotation. The x-axis and y-axis define a horizontal plane, and the z-axis defines a vertical direction. The Cartesian coordinate system is not intended to limit the invention, but is used for illustration purposes only. Alternatively, other coordinate systems, such as a cylindrical coordinate system, may be used to clarify the invention. The orientation of the Cartesian coordinate system may be different, for example, such that the z-axis has a component along the horizontal plane.

[0026] Immersion techniques have been introduced into lithography systems to enable improved resolution of smaller features. In an immersion lithography apparatus, a layer of immersion liquid having a relatively high refractive index is interposed in an immersion space 11 between the apparatus's projection system PS (through which a patterned beam is projected towards the substrate W) and the substrate W. The immersion liquid covers at least a portion of the substrate W below the final element of the projection system PS. Thus, at least a portion of the substrate W during exposure is immersed in the immersion liquid.

[0027] In commercial immersion lithography, the immersion liquid is water. The water is typically high purity distilled water, such as ultrapure water (UPW), commonly used in semiconductor manufacturing plants. In immersion systems, the UPW is frequently purified and may have to undergo additional processing steps before being supplied as the immersion liquid to the immersion space 11. Other liquids than water, such as hydrocarbons, such as fluorocarbons, and / or aqueous solutions, having a high refractive index may also be used as the immersion liquid. Additionally, other fluids than liquids are anticipated for use in immersion lithography.

[0028] Reference is made herein to localized immersion, where the immersion liquid in use is confined to an immersion space 11 between a final element and a surface facing the final element. The facing surface is the surface of the substrate W or a surface of the support stage (or substrate support WT) that is flush with the surface of the substrate W (note that references in the following text to the surface of the substrate W may additionally or alternatively refer to the surface of the substrate support WT and vice versa, unless otherwise stated). A fluid handling structure IH present between the projection system PS and the substrate support WT is used to confine the immersion liquid to the immersion space 11. The immersion space 11, filled with immersion liquid, is smaller in plan than the top surface of the substrate W and remains substantially stationary relative to the projection system PS while the substrate W and substrate support WT move underneath.

[0029] Other immersion systems are also envisaged, such as unconfined immersion systems (so-called "all wet" immersion systems) and bath-based immersion systems. In unconfined immersion systems, the immersion liquid covers more than the surface below the final element. The liquid outside the immersion space 11 is present as a thin liquid film. The liquid may cover the entire surface of the substrate W or the substrate W and a substrate support WT flush with the substrate W. In a bath-based system, the substrate W is completely immersed in a bath of immersion liquid.

[0030] The fluid handling structure IH is a structure which supplies immersion liquid to and removes immersion liquid from the immersion space 11, thereby confining the immersion liquid to the immersion space 11. It includes features which are part of a fluid supply system. The arrangement disclosed in PCT Patent Application Publication No. WO 99 / 49504 is an early fluid handling structure which comprises pipes which supply or withdraw immersion liquid from the immersion space 11 and which operate in response to relative movement of a stage below the projection system PS. In newer designs, the fluid handling structure extends along at least part of the boundary of the immersion space 11 between the final element of the projection system PS and the substrate support WT or substrate W, and partly defines the immersion space 11.

[0031] The fluid handling structure IH may have a choice of different functions, each of which may result from corresponding features that enable the fluid handling structure IH to realise that function. The fluid handling structure IH may be represented by a number of different terms, each representing a function, such as barrier member, sealing member, fluid supply system, fluid removal system, liquid confinement structure, etc.

[0032] The fluid handling structure IH as a barrier member is a barrier to a flow of immersion liquid from the immersion space 11. As a liquid confinement structure the structure confines the immersion liquid to the immersion space 11. As a seal member the sealing features of the fluid handling structure IH form a seal to confine the immersion liquid to the immersion space 11. The sealing features may include an additional gas flow from openings in the surface of the seal member, such as a gas knife.

[0033] In an embodiment, the fluid handling structure IH may provide the immersion fluid as the fluid supply system.

[0034] In an embodiment, the fluid handling structure IH may at least partly confine the immersion fluid as a fluid containment system.

[0035] In an embodiment, the fluid handling structure IH may provide a barrier to the immersion fluid as a barrier member, such as a fluid confinement structure.

[0036] In an embodiment, the fluid handling structure IH may generate or use a flow of gas, for example to help control the flow and / or position of the immersion fluid.

[0037] The gas flow may form a seal to confine the immersion fluid and the fluid handling structure IH may be referred to as a sealing member. Such a sealing member may be a fluid confinement structure.

[0038] In an embodiment, an immersion liquid is used as the immersion fluid. The fluid handling structure IH in this case may be a liquid handling system. With reference to the above description, references in these paragraphs to features defined with respect to a fluid are understood to include features defined with respect to a liquid.

[0039] The lithographic apparatus comprises a projection system PS. During exposure of a substrate W, the projection system PS projects a patterned beam of radiation onto the substrate W. To reach the substrate W, the path of a radiation beam B passes from the projection system PS through an immersion liquid confined by a fluid handling structure IH between the projection system PS and the substrate W. The projection system PS has a lens element that contacts the immersion liquid at the end of the beam's path. This lens element that contacts the immersion liquid may be referred to as the "final lens element" or "final element". The final element is at least partly surrounded by a fluid handling structure IH. The fluid handling structure IH may confine immersion liquid below the final element and above an opposing surface.

[0040] 1, in an embodiment, the lithographic apparatus comprises a controller 500. The controller 500 is configured to control a substrate table WT.

[0041] Figure 2 shows diagrammatically a localised liquid supply or fluid handling system. The liquid supply system is provided with a fluid handling structure IH (or liquid confinement structure) that extends along at least part of the boundary of the space 11 between the final element of the projection system PS and the support table WT or substrate W. The fluid handling structure IH is substantially stationary in the XY plane relative to the projection system PS, although there may be relative movement in the Z direction (in the direction of the optical axis). In examples, a seal, which may be a contactless seal such as a gas seal (such a system having a gas seal is disclosed in EP 1,420,298) or a liquid seal, is formed between the fluid handling structure IH and the surface of the substrate W.

[0042] The fluid handling structure IH at least partly confines immersion liquid to a space 11 between the final element of the projection system PS and the substrate W. The space 11 is at least partly formed by the fluid handling structure IH which is located below and surrounds the final element of the projection system PS. Immersion liquid is supplied into the space 11 below the projection system PS and in the fluid handling structure IH by one liquid opening 13. Immersion liquid may be removed by the other liquid opening 13. Immersion liquid may be supplied into the space 11 through at least two liquid openings 13. Which liquid opening 13 is used to supply immersion liquid, and optionally which is used to remove immersion liquid, may depend on the direction of movement of the support table WT.

[0043] The immersion liquid may be confined to the space 11 by a contactless seal, such as a gas seal 16 formed by gas forming between the bottom of the fluid handling structure IH and the surface of the substrate W during use. Gas in the gas seal 16 is provided under pressure via an inlet 15 to the gap between the fluid handling structure IH and the substrate W. Gas is removed via an outlet 14. The positive pressure at the gas inlet 15, the vacuum level at the outlet 14 and the geometry of the gap are adjusted to create a high velocity inward gas flow that confines the immersion liquid. Such a system is disclosed in US2004 / 0207824, which is incorporated herein by reference in its entirety. In one example, the fluid handling structure IH does not have a gas seal 16.

[0044] Figure 3 shows a cross-sectional side view of a further liquid supply system or fluid handling system according to an embodiment. The arrangement illustrated in Figure 3 and described below may be applied to a lithographic apparatus as previously described and illustrated in Figure 1. The liquid supply system is provided together with a fluid handling structure IH (or liquid confinement structure) that extends along at least part of the boundary of a space 11 between the final element of the projection system PS and the support table WT or substrate W.

[0045] The fluid handling structure IH at least partly confines immersion liquid to a space 11 between the final element of the projection system PS and the substrate W. The space 11 is at least partly formed by the fluid handling structure IH underlying and surrounding the final element of the projection system PS. In an example, the fluid handling structure IH comprises a body member 53 and a porous member 33. The porous member 33 is plate-like and has a plurality of holes (i.e. openings or pores). In an embodiment, the porous member 33 is a mesh plate in which a large number of small holes 84 are formed in a mesh. Such a system is disclosed in US2010 / 0045949A1, which is incorporated herein by reference in its entirety.

[0046] The body member 53 comprises a supply port 72 capable of supplying immersion liquid to the space 11, and a recovery port 73 capable of recovering immersion liquid from the space 11. The supply port 72 is connected to a liquid supply unit 75 via a flow path 74. The liquid supply unit 75 is capable of supplying immersion liquid to the supply port 72 through the corresponding flow path 74. The recovery port 73 is capable of recovering immersion liquid from the space 11. The recovery port 73 is connected to a liquid recovery unit 80 via a flow path 79. The liquid recovery unit 80 recovers the immersion liquid recovered via the recovery port 73 through the flow path 79. The porous member 33 is arranged at the recovery port 73. By performing a liquid supply operation using the supply port 72 and performing a liquid recovery operation using the porous member 33, a space 11 is formed which is between the projection system PS and the fluid handling structure IH on one side and has the substrate W on the other side.

[0047] Figure 4 illustrates a part of a lithographic apparatus useful for the understanding of an embodiment of the present invention. The arrangement illustrated in Figure 4 and described below may be applied to the lithographic apparatus previously described and illustrated in Figure 1. Figure 4 is a cross-section of a substrate support 20 and a substrate W. In an embodiment, the substrate support 20 comprises one or more conditioning channels 61 of a thermal conditioner 60, which will be described in more detail below. A gap 5 exists between an edge of the substrate W and an edge of the substrate support 20. When the edge of the substrate W is being imaged, or at other times, such as when the substrate W first moves under the projection system PS (as described above), the immersion space 11, which is filled with liquid by the fluid handling structure IH (for example), at least partially passes through the gap 5 between the edge of the substrate W and the edge of the substrate support 20. Thus, liquid from the immersion space 11 may flow into the gap 5.

[0048] The substrate W is held by a first support 21 (e.g. a pimple or burl table) which comprises one or more protrusions 41 (i.e. burls). The first support 21 is an example of an object holder. Another example of an object holder is a mask holder. Negative pressure applied between the substrate W and the substrate support 20 may ensure that the substrate W is held securely in place. However, if immersion liquid gets between the substrate W and the first support 21 this may cause difficulties, especially when removing the substrate W.

[0049] To deal with immersion liquid entering the gap 5, at least one drain 10, 12 is provided at the edge of the substrate W for removing the immersion liquid that has entered the gap 5. There may be only one drain or more than two, however in one embodiment of Figure 4 two drains 10, 12 are illustrated. In one embodiment, each of the drains 10, 12 is annular around the entire periphery of the substrate W.

[0050] The main function of the first drain 10 (radially outside the edge of the substrate W / first support 21) is to prevent gas bubbles from entering the immersion space 11 in which the liquid of the fluid handling structure IH is present. Such bubbles may have a detrimental effect on imaging of the substrate W. The first drain 10 is present to avoid gas in the gap 5 escaping into the immersion space 11 in the fluid handling structure IH. Gas escaping into the immersion space 11 may result in bubbles floating in the immersion space 11. If such bubbles end up in the path of the projection beam they will lead to imaging errors. The first drain 10 is configured to remove gas from the gap 5 between the edge of the substrate W and the edge of a recess in the substrate support 20 in which the substrate W is located. The edge of the recess in the substrate support 20 may be defined by a covering ring 101, which is optionally separated from the first support 21 of the substrate support 20. The covering ring 101 may be ring-shaped in plan and may surround the outer periphery of the substrate W. The first drain 10 removes most of the gas and a very small amount of immersion liquid.

[0051] A second drain 12 (radially inward of the edge of the substrate W / first support 21) is provided to prevent liquid from passing through the gap 5 under the substrate W so as to prevent efficient release of the substrate W from the substrate table WT after imaging. The provision of the second drain 12 reduces or eliminates problems that can be caused by liquid passing under the substrate W.

[0052] As shown in Figure 4, in one embodiment, the lithographic apparatus comprises a first outlet channel 102 for the flow of two-phase flow. The first outlet channel 102 is formed in the block. First and second drains 10, 12 are provided with respective openings 107, 117 and respective outlet channels 102, 113. The outlet channels 102, 113 communicate fluid between the respective openings 107, 117 through respective flow paths 103, 114.

[0053] As shown in Figure 4, the cover ring 101 has an upper surface. The upper surface extends circumferentially around the substrate W on the first support 21. In use of the lithographic apparatus, the fluid handling structure IH moves relative to the substrate support 20. During this relative movement, the fluid handling structure IH passes through the gap 5 between the cover ring 101 and the substrate W. In an embodiment, the relative movement is provided by the substrate support 20 moving below the fluid handling structure IH. In an alternative embodiment, the relative movement is provided by the fluid handling structure IH moving above the substrate support 20. In a further alternative embodiment, the relative movement is provided by both movement of the substrate support 20 below the fluid handling structure IH and movement of the fluid handling structure IH above the substrate support 20. In the following description, movement of the fluid handling structure IH is used to mean relative movement of the fluid handling structure IH with respect to the substrate support 20.

[0054] 5 is a schematic diagram of a substrate support 20 according to an embodiment of the invention. The substrate support 20 is for supporting a substrate W in a lithographic apparatus (e.g. the lithographic apparatus shown in FIG. 1). During an exposure process, the substrate W is supported on the substrate support 20. Between multiple exposure processes, the substrate W on the substrate support 20 may be exchanged. During this time, the substrate support 20 may not support any substrate W.

[0055] As shown in Figure 5, in one embodiment, the substrate support 20 comprises a first support 21. The first support 21 is configured to support the substrate W. When the substrate W is supported by the substrate support 20, the substrate W is in direct contact with the first support 21. The first support 21 is a part of the substrate support 20 that physically supports the underside of the substrate W. As shown in Figure 5, in one embodiment, the first support 21 comprises a plurality of burls 41. Ends of the burls 41 form a surface on which the underside of the substrate W is supported. The underside of the substrate W contacts the ends of the burls 41. The burls 41 are on an upper side of the first support 21.

[0056] As shown in FIG. 5, in one embodiment, there is a space 42 between the underside of the substrate W and the upper base surface of the first support 21 (between the multiple burls 41). In one embodiment, the substrate support 20 comprises a clamp configured to hold the substrate W on the first support 21. For example, as shown in FIG. 5, in one embodiment, the substrate support 20 comprises a clamp comprising a clamp channel 43. The clamp channel 43 is configured to extract gas from the space 42 between the substrate W and the first support 21. The clamp channel 43 is in fluid communication with the space 42. As shown in FIG. 5, in one embodiment, the clamp channel 43 is in fluid communication with the space 42 via one or more clamp channels 44. In one embodiment, the clamp channel 43 has a ring shape surrounding the center of the substrate support 20. The clamp channel 43 extends in a circumferential direction. In one embodiment, multiple clamp channels 44 extend vertically to connect the clamp channel 43 to the space 42.

[0057] 5, in one embodiment, the substrate support 20 comprises a body 22. The body 22 is separated from a first support 21. The first support 21 can be separated from the body 22 without substantially damaging the body 22. The first support 21 can be removed from the body 22 and repositioned on the body 22. The body 22 is configured to support the first support 21.

[0058] While the substrate support 20 is in use, it will wear out. For example, the ends of the burls 41 will wear out over time. Even if the burls 41 wear out, it is not necessary to replace the entire substrate support 20, but the first support 21 can be replaced. For example, the first support 21 may be replaced without replacing the body 22. In one embodiment, the first support 21 is removed from the body 22. The replaced first support 21 is placed on the body 22. The exposure process is then continued using the replaced first support 21. It is expected that embodiments of the invention will reduce the cost of maintaining the availability of the substrate support 20.

[0059] The first support 21 can be replaced faster compared to replacing the entire substrate support 20. Embodiments of the invention are expected to reduce the downtime of the lithographic apparatus required to maintain the substrate support 20.

[0060] As shown in Fig. 5, in one embodiment, the body 22 comprises a thermal conditioner 60. In one embodiment, the thermal conditioner 60 is configured to thermally condition the body 22. Additionally or alternatively, the thermal conditioner 60 is configured to thermally condition the first support 21. Additionally or alternatively, the thermal conditioner 60 is configured to thermally condition the substrate W. By thermally conditioning the body 22, the first support 21 and / or the substrate W, a temperature profile may be controlled. In particular, deformations caused by thermal fluctuations may be reduced. By reducing the deformations, the accuracy of the exposure process may be improved.

[0061] The manner in which thermal conditioner 60 thermally conditions is not particularly limited. By way of example only, as shown in FIG. 5, in one embodiment, thermal conditioner 60 includes one or more conditioning channels 61. Conditioning channels 61 may extend through body 22. In one embodiment, conditioning channels 61 contain a fluid (e.g., a gas and / or a liquid).

[0062] 1 , in one embodiment, the lithographic apparatus comprises a controller 500. In one embodiment, the controller 500 is configured to control a flow or fluid through one or more conditioning channels 61. In one embodiment, the controller 500 is configured to control a flow of fluid through the conditioning channels 61 to control a temperature profile of the target (e.g., the body 22, the first support 21 and / or the substrate W).

[0063] 5, in one embodiment, the thermal conditioner 60 includes one or more sensors 62. In one embodiment, the sensor 62 is attached to or embedded in the body 22. In one embodiment, the sensor 62 is a temperature sensor. In one embodiment, the sensor 62 may be configured to measure the temperature of the fluid flowing within the conditioning channel 61. In one embodiment, multiple sensors 62 are provided at different positions along the conditioning channel 61 to sense the temperature profile across the conditioning channel 61.

[0064] As shown in Fig. 5, in one embodiment, the thermal conditioner 60 includes one or more heaters 63. As shown in Fig. 5, in one embodiment, the heaters 63 are attached to the underside of the body 22. However, the heaters 63 may be located on other surfaces of the body 22 or the first support 21. Additionally or alternatively, sensors may be provided on the surfaces of the body 22 and / or the first support 21. In one embodiment, the controller 500 is configured to receive signals from the sensors 62 and subsequently control the flow of fluid through the heaters 63 and / or the regulation channels 61.

[0065] In the substrate support 20, the function of physically supporting (and clamping) the substrate W is performed by the first support 21, while the function of thermal stabilization is performed by the body 22. The first support 21 is separate from the body 22. The functions of supporting the substrate W and of thermal stabilization are separated into different components. If one function is lost (or no longer meets a required level of performance), the corresponding component can be replaced without replacing the other component. It is expected that embodiments of the invention will facilitate maintaining the substrate support 20 such that the functions performed meet the required level.

[0066] As shown in FIG. 5, in one embodiment, the substrate support 20 comprises an extraction body 100. The extraction body 100 surrounds the main body 22 and the first support 21. The extraction body 100 is radially outside the main body 22 and the first support 21. As shown in FIG. 5, in one embodiment, the extraction body 100 is provided in a component separate from the main body 22. However, it is not essential that the extraction body 100 is separate from the main body 22 and the first support 21. As will be described in more detail below, the extraction body 100 may be part of the same component as the main body 22. In such an embodiment, the extraction body 100 can only be replaced together with the main body 22 (and vice versa). In one embodiment, the extraction body 100 is part of the same component as the main body 22, as shown, for example, in FIGS. 7 to 10. The extraction body 100 may be integrally formed with the main body 22. The extraction body 100 and the main body 22 are formed together as one component. The extraction body 100 and the main body 22 are inseparable from one another. In an alternative embodiment, the extraction body 100 is integrally formed with the substrate stage .

[0067] As shown in FIG. 5, in an embodiment, the extraction body 100 comprises a first extraction channel 102. In an embodiment, the extraction body 100 comprises the first drain 10 described above. The first extraction channel 102 is configured to extract fluid from near the periphery of the substrate W. As shown in FIG. 5, in an embodiment, the first extraction channel 102 is configured to extract fluid from radially outside the periphery of the substrate W. The first extraction channel 102 is configured to remove bubbles that may occur in the immersion liquid used in the lithographic apparatus. The first extraction channel 102 contributes to reducing image defects by reducing bubbles and / or by reducing the occurrence of, for example, watermarks.

[0068] As mentioned above, the extraction body 100 is configured to reduce defect problems. The functions performed by the extraction body 100 may be different from the functions performed by the first support 21 and the body 22. If one function is lost or no longer meets a required level of performance, the corresponding component (e.g., the extraction body 100, the first support 21 or the body 22) may be replaced without replacing other components of the substrate support 20.

[0069] Fig. 6 shows a schematic diagram of a substrate support 20 according to a comparative example. In the comparative example shown in Fig. 6, both the function of supporting (and clamping) the substrate W and the function of thermally conditioning the substrate W are performed in the same component. Thus, if the tip of the burl 41 is worn out, the entire body 22, including both the thermal conditioner 60 and the burl 41 supporting the substrate W, must be replaced. For example, replacement of the entire body 22 may be required even if the thermal conditioner 60 is still operating normally and does not need to be replaced.

[0070] As shown in FIG. 5, in one embodiment, a seal member 27 is provided to seal the gap between the substrate support 20 and the substrate stage 26 that supports the substrate support 20. In the comparative example shown in FIG. 6, the seal member 27 also needs to be removed and replaced when the substrate support 20 is replaced. In contrast, in the embodiment shown in FIG. 5, the removal body 100 and the seal member 27 remain in place while the first support 21 and / or the body 22 are replaced. Similarly, in an embodiment where the removal body 100 is part of the same component as the body 22, the removal body 100 and the seal member 27 remain in place while the first support 21 is replaced. It is expected that the embodiments of the invention will reduce the time required to maintain the substrate support 20.

[0071] 5, in one embodiment, the substrate support 20 comprises a second support 23. The second support 23 is separate from the body 22. The second support 23 is configured to support the body 22 on the substrate stage 26. In one embodiment, the body 22 is in physical contact with the second support 23. For example, in one embodiment, the underside of the body 22 is supported on an upper portion of the second support 23. The second support 23 is supported on the substrate stage 26.

[0072] As shown in FIG. 5, in one embodiment, the second support 23 comprises a number of burls 91. In one embodiment, the burls 91 of the second support 23 are longer than the burls 41 of the first support 21. The burls 91 protrude from the underside of the second support 23. These burls 91 extend towards and are supported by the substrate stage 26. In one embodiment, the second support 23 is configured to reduce relative movement between the substrate support 20 and the substrate stage 26. The second support 23 is configured to reduce slippage between the substrate support 20 and the substrate stage 26. During use of the lithographic apparatus, the substrate stage 20 experiences large accelerations. If the substrate support 20 slips relative to the substrate stage 26, this may lead to undesirable overlay errors. The burls 91 are configured to grip the substrate stage 26 and reduce slippage of the substrate support 20 relative to the substrate stage 26.

[0073] The second support 23 can be physically separated from the body 22 without damaging the body 22 or the second support 23. One or the other of the body 22 and the second support 23 can be replaced without replacing the other. For example, if the anti-slip function of the second support 23 no longer meets a required performance level, the second support 23 can be replaced without replacing the body 22. Embodiments of the invention are expected to reduce the cost of maintaining the substrate support 20.

[0074] In another example, the body 22 may be replaced, for example when replacement of the thermal conditioner 60 is required. The body 22 may be replaced without replacing (or substantially moving) the second support 23. Embodiments of the invention are expected to reduce the cost of maintaining the substrate support 20.

[0075] However, it is not essential that the substrate support 20 comprises such a second support 23. For example, as shown in Figures 7 to 12, the function of reducing slippage of the substrate support 20 relative to the substrate stage 26 may be performed by the body 22. A burl 91 may be provided in the lower part of the body 22.

[0076] As shown in Figures 5 and 7, for example, in one embodiment, the body 22 comprises a plurality of burls 65 on its upper side. The burls 65 have in-plane ends. The burls 65 are configured to support the first support 21. By providing the burls 65 on the upper side of the body 22, the structure of the first support 21 can be kept simple. The underside of the first support 21 may be flat and substantially featureless. The upper side of the first support comprises burls 41 for supporting the substrate W. It is expected that embodiments of the invention will enable components for clamping the substrate W to be inexpensively manufactured.

[0077] In addition, as shown in Figures 5 and 8 to 10, for example, in one embodiment, the first support 21 includes a plurality of sealing protrusions 46. The sealing protrusions 46 protrude on an upper side of the first support 21. The sealing protrusions 46 are shorter than the burls 41. The sealing protrusions 46 do not contact the substrate W. There is a small gap between the top of the sealing protrusions 46 and the underside of the substrate W. In one embodiment, the sealing protrusions 46 extend circumferentially around the first support 21, i.e., the sealing protrusions 46 each form a ring. The sealing protrusions 46 are configured to reduce the amount of fluid passing through the sealing protrusions 46.

[0078] However, it is not essential that the body 22 is provided with burls 65. For example, in an alternative embodiment shown in FIG. 8, the first support 21 comprises a plurality of burls 47 on its underside. The burls 47 have ends in the plane. The burls 47 are configured to contact the upper side of the body 22. Instead of the burls 65 provided on the body 22 as shown in FIG. 8, a different set of burls 47 may be provided on the underside of the first support 21. During use, the burls 41, 47 may wear out before other parts of the substrate support 20 wear out. By providing both sets of burls 41, 47 on the first support 21, the burls may be replaced by simply replacing the first support 21 without replacing the body 22. It is expected that the embodiments of the invention will reduce the cost of maintaining the substrate support 20.

[0079] As shown in FIG. 5, in one embodiment, the extraction body 100 comprises a second extraction channel 113. This is also shown in other figures. The second extraction channel 113 is part of the second drain 12. In one embodiment, the second extraction channel 113 is configured to extract fluid from the radially inner side of the first extraction channel 102. In one embodiment, the second extraction channel 113 is provided to prevent liquid from flowing under the substrate W. However, it is not essential that such a second extraction channel 113 is provided. For example, FIG. 10 shows an embodiment without the second extraction channel 113.

[0080] In one embodiment, the second outflow channel 113 is configured to extract fluid from below the periphery of the substrate W to prevent liquid from reaching the space 42 between the center W of the substrate and the first support 21. As shown in FIG. 4, in one embodiment, the second outflow channel 113 is connected to the space below the periphery of the substrate W via one or more second flow paths 114. In one embodiment, the second outflow channel 113 extends circumferentially around the substrate support 20. In one embodiment, multiple second flow paths 114 are provided. The second flow paths 114 extend vertically between the second outflow channel 113 and just below the periphery of the substrate W.

[0081] As shown in FIG. 5, in one embodiment, the second out-channel 113 is separated from the first out-channel 102 by an open gap. The first out-channel 102 and the second out-channel 113 may be provided in separate bodies 24, 25. The separate bodies 24, 25 may be separated from each other without breaking any of the separate bodies 24, 25. The function of reducing defect problems (performed by the first out-channel 102) and the function of preventing liquid from flowing under the substrate W (performed by the second out-channel 113) may be performed by the separate bodies 24, 25. One of the separate bodies 24, 25 can be replaced without replacing the other. An embodiment of the invention is expected to reduce the cost of maintaining the substrate support 20.

[0082] As shown in FIG. 7 (and also visible, for example, in FIGS. 5 and 8), in one embodiment, the substrate support 20 comprises an inner seal 112 and an outer seal 111. The inner seal 112 is located radially inside the opening through which the second outflow channel 113 extracts fluid. The outer seal 111 is located radially outside the opening through which the second outflow channel 113 extracts fluid. The inner seal 112 and the outer seal 111 protrude towards the underside of the substrate W. The inner seal 112 and the outer seal 111 do not protrude enough to contact the substrate W during use with the substrate support 20. Instead, there are small gaps between the top of the inner seal 112 and the substrate W, and between the top of the outer seal 111 and the substrate W. The inner seal 112 and the outer seal 111 are configured such that liquid may be present between the seals 111, 112 and the substrate W during use. This helps to prevent liquid from reaching below the substrate W at the center of the substrate W.

[0083] As shown in Figure 9, in one embodiment the function of the inner seal 112 is performed by a sealing protrusion 46 on the upper side of the first support 21. This is instead of the arrangement shown in Figure 7, for example, where the inner seal 112 is provided as a protrusion on the upper side of the body 22. As shown in Figure 9, in one embodiment an upper flow path 49 is provided through the first support 21. The upper flow path 49 connects with a second flow path 114 such that fluid can be extracted from below the periphery of the substrate W into a second extraction channel 113.

[0084] 9, for example, in one embodiment, the body 22 includes a sealing protrusion 66. The sealing protrusion 66 is configured to reduce the likelihood of moisture reaching the top surface of the body 22. This reduces oxidation of the body 22.

[0085] As shown in FIG. 10, in one embodiment, the substrate support 20 is not provided with a second extraction channel 113, as shown in, for example, FIGS. 5 to 9. As shown in FIG. 10, in one embodiment, an open gap or passage 115 is formed between the extraction body 100, the main body 22, and the first support 21. In one embodiment, the open gap or passage 115 communicates fluid between atmospheric pressure or a pressure source. In one embodiment, the multiple passages 115 extend primarily vertically through the body 22 (which may be part of the same component as the extraction body 100). In an alternative embodiment, the open gap extends circumferentially around the body 22, and the extraction body 100 may be provided as a different component from the body 22. In one embodiment, a gas flow passes through the open gap or passage 115. The gas flow passes through the seal protrusion 46 at the top periphery of the first support 21. By providing a gas flow, the possibility of liquid reaching the underside of the substrate W beyond the seal protrusion 46 may be reduced. It is not necessary to provide the second extraction channel 113. Embodiments of the invention are expected to reduce the complexity of the substrate support 20. Embodiments of the invention are expected to facilitate the manufacture of the substrate support 20.

[0086] As previously described and illustrated in Figures 5 and 7 to 10, the substrate support 20 can be modularized in various ways. As shown in Figure 11, in one embodiment, an extraction body 100 is provided with both a first extraction channel 102 and a second extraction channel 113. The extraction body 100 is separate from both the first support 21 and the body 22. The body 22 is supported directly on the substrate stage 26 (i.e., without the second support 23). As shown in Figure 11, the inner seal 112 and the outer seal 111 are provided as part of the extraction body 100. This reduces the radial dimension of the first support 21 (as the first support 21 does not need an additional seal protrusion 46 to perform the function of the inner seal 112). This reduces the amount of substrate support 20 to be replaced when a worn burl 41 needs to be replaced.

[0087] 11, in one embodiment, the body 22 extends below the ejection body 100. The underside of the ejection body 100 is coupled to the body 22. This facilitates control of the height of the ejection body 100 relative to the first support 21. By more precisely controlling the height of the ejection body 100, the reliability of the sealing function provided by the inner seal 112 and the outer seal 111 is increased.

[0088] As shown in FIG. 11, in one embodiment, one or more holes 119 are provided in the body 22. The holes 119 are configured to communicate fluid between the radial interior of the extractor 100 and the gap between the body 22. The holes 119 may be connected to other holes extending through the substrate stage 26. The holes 119 are configured to provide atmospheric or pressurized gas. By providing gas flow upward through the holes 119, the likelihood of liquid reaching below the center of the substrate W is reduced. By providing gas flow through the holes 119, the transfer of moisture to the first support 21 is reduced. By reducing the transfer of moisture to the first support 21, oxidation of the first support 21 is reduced.

[0089] In one embodiment, the holes 119 are configured to provide pressurized gas. By providing a pressurized gas flow, lifting of the edge of the substrate W can be controlled. By controlling the lifting of the outer edge of the substrate W, wear on the outermost burls 41 of the first support 21 can be reduced. Embodiments of the invention are expected to reduce wear on the substrate support 20.

[0090] 11, in one embodiment, an adhesive layer 104 is provided between the extraction body 100 and the main body 22. The adhesive layer 104 secures the extraction body 100 to the main body 22. This facilitates control of the gap from the substrate W to the inner seal 112 and the outer seal 111 of the extraction body 100.

[0091] In one embodiment, beads are dispersed in the adhesive layer 104. For example, glass beads may be dispersed in the adhesive. The size of the beads may be selected to provide the required height step between the tops of the inner / outer seals 111, 112 and the tops of the seal projections 66 on the outermost radial portion of the body 22. In one embodiment, the beads have a diameter of, for example, 45 microns, 50 microns or 55 microns.

[0092] 11, in one embodiment, a fluid connection is maintained from the first / second outtake channel 102, 113 through the body 22 (to which the outtake body 100 is attached) and then through the substrate stage 26. The fluid connection may be maintained by a dogbone connector 105 and a ring 106. However, the connection between the outtake body 100 and the body 22 for purposes of the first / second outtake channel 102, 113 is not particularly limited.

[0093] It is not essential that the body 22 extends below the extraction body 100. In an alternative embodiment, the underside of the extraction body 100 is attached to the substrate stage 26. In one embodiment, the substrate table WT (comprising the substrate stage 26 and the substrate support 20) comprises a height adjustment mechanism 130. An alternative version of the height adjustment mechanism 130 is shown, for example, in Figs. 12 and 13. The height adjustment mechanism 130 is configured to provide a fine adjustable height adjustment to obtain a suitable sealing gap between the extraction body 100 and the substrate W. The height adjustment mechanism 130 is configured to control the height of at least a portion of the extraction body 100 below the substrate W such that the extraction body 100 is configured to prevent liquid from reaching between the center of the substrate W and the first support 21.

[0094] 12, in one embodiment, the height adjustment mechanism 130 includes an insert member 131. The insert member 131 is a block of material. The insert member 131 is provided between the underside of the extraction body 100 and the substrate stage 26. The insert member 131 is separate from the main body 22. The insert member 131 is a component that attaches the extraction body 100 to the substrate stage 26.

[0095] 12, in one embodiment, the height adjustment mechanism 130 includes a fastener 132. For example, in one embodiment, the fastener 132 is a bolt. As shown in FIG. 12, in one embodiment, the fastener 132 does not reach the substrate stage 26. The fastener 132 connects the extraction body 100 to the insert member 131.

[0096] 12, in one embodiment, the extractor 100 includes a protrusion 134 configured to engage with an insert member 131. As shown in FIG. 12, in one embodiment, the insert member 131 is bonded onto the substrate stage 26.

[0097] 12, in one embodiment, the insert member 131 is configured with a notch 133 such that when the fastener 132 couples the extraction body 100 to the insert member 131, the insert member 131 is compressed. The compression of the insert member 131 can be controlled to control the height of the top of the extraction body 100 below the substrate W. In particular, the force provided by the fastener 132 can be controlled to control the compression of the insert member 131.

[0098] 12 shows the stress lines 135 passing through the fasteners 132 and the solid portion of the insert member 131 (i.e., between the notches 133). As shown in FIG. 12, the notches 133 may be provided so that the lines of force 135 pass through a relatively narrow portion of the insert member 131. If the narrow portion of the insert member 131 is relatively flexible, it is easier to control the compression of the insert member 131. This helps to control the height of the extractor 100 below the substrate W. In particular, the narrow portion of the insert member 131 between the notches 133 may act as a leaf spring (or other flexible portion).

[0099] The height adjustment mechanism 130 shown in FIG. 12 is only one example. As another example, an alternative height adjustment mechanism 130 is shown in FIG. 13. As shown in FIG. 13, in one embodiment, the ejection body 100 comprises a leaf spring 141. The leaf spring 141 comprises a lower portion 142 that is fixed to the remainder of the ejection body 100. The leaf spring 141 further comprises an upper portion 143 that extends between the ejection body 100 and the first support 21. In one embodiment, a plurality of such leaf springs 141 are provided circumferentially around the substrate support 20. In an alternative embodiment, a single leaf spring 141 extends circumferentially around the substrate support 20.

[0100] As shown in FIG. 13, in one embodiment, the height adjustment mechanism 130 is configured to control the height of the upper portion 143 below the substrate W such that the upper portion 143 is configured to prevent liquid from reaching between the center of the substrate W and the first support 21. In one embodiment, a set screw 144 is provided to allow fine adjustment of the leaf spring 141. The set screw 144 can protrude a controlled distance below the extraction body 100. When the set screw 144 protrudes further from the bottom of the extraction body 100, the set screw 144 bends the leaf spring 141, lowering the height of the upper portion 143 of the leaf spring 141. As shown in FIG. 13, in one embodiment, the first extraction channel 102 may be connected to the second extraction channel 113 via the connecting channel 140.

[0101] The manner in which the thermal conditioner 60 is provided on the body 22 is not particularly limited. In one embodiment, the thermal conditioner 60 is attached under the surface of the body 22. For example, one or more Peltier elements and / or heaters may be provided on the underside of the body 22 and / or the extraction body 100. Additionally or alternatively, the channel 61, one or more Peltier elements and / or heaters 63 may be provided on the periphery of the lower part of the body 22. In an alternative embodiment, the thermal conditioner 60 is attached to the upper side of the body 22. The external channel 61 and / or one or more Peltier elements and / or heaters 63 may be attached (e.g., glued on the body 22). In one embodiment, the channel 61, heater 63 and / or sensor 62 are provided on the substrate stage 26. At least a part of the thermal adjustment function is performed by the substrate stage 26. This helps to simplify the design of the body 22. In one embodiment, a crowbar 91 is provided as part of the substrate stage 26. The body 22 may not include a burl 91. The underside of the body 22 may be substantially flat. In one embodiment, at least one sensor 62 is provided on each burl 91 of the substrate stage 26. The sensor 62 is configured to measure a temperature of the body 22. The sensor 62 is located proximate to the body 22. In one embodiment, at least one heater 63 is provided on a surface of the substrate stage 26 opposite the body 22. In one embodiment, a heater 63 is paired with each sensor 62. The heater 63 is located proximate to each sensor 62. In one embodiment, the heater 63 is controlled based on an output from the paired sensor 62.

[0102] As shown in FIG. 5, in one embodiment, a clamping channel 43 is in fluid communication with the space 42 through another space 45 between the body 22 and the first support 21 .

[0103] 5, in one embodiment, the substrate support 20 is locked to the substrate stage 26 by at least one fastening bolt 29. In one embodiment, the fastening bolt 29 is configured to act as a safety lock to prevent the substrate support 20 from falling off the substrate stage 26. However, a crowbar 91 performs the function of preventing the substrate support 20 from slipping relative to the substrate stage 26.

[0104] 5, in one embodiment, one or more pins 28 may be used to lower the substrate W onto the first support 21. The pins 28 support the substrate W through respective pinholes 121 in the substrate support 20 to control the height of the substrate W above the first support 21 during loading and unloading sequences.

[0105] 7, in one embodiment, the body 22 is formed in two sections that are attached to one another at bond lines 64. For example, an adhesive material may be used.

[0106] As mentioned above, the first support 21 may be replaced without also replacing other parts of the substrate holder 20. As illustrated, the first support 21 has a generally similar shape to the substrate W. In an embodiment, the lithographic apparatus comprises at least one handling tool configured to drive the substrate W, e.g. to drive the substrate W between different parts of the lithographic apparatus and / or to drive the substrate W in and out of the lithographic apparatus. In an embodiment, the same handling tool may be used to control the movement of the first support 21.

[0107] 14 is a schematic cross-sectional view of a carrier plate 120 coupled to the first support 21 according to an embodiment of the invention. The carrier plate 120 is configured to be coupleable to the first support 21. The carrier plate 120 is configured to be releasable (removable) from the first support 21. As shown in FIG. 14, in one embodiment, the carrier plate 120 is configured to cover a pinhole 121 in the first support 21 when the carrier plate 120 is coupled to the first support 21.

[0108] As mentioned above, in one embodiment, a plurality of pins 28 support the substrate W and can be controlled to lower the substrate W onto the substrate support 20. FIG. 15 shows an assembly of a carrier plate 120 and a first support 21 supported by pins 28. By providing the carrier plate 120 covering the pin holes 121, the first support 21 is effectively coupled to the carrier plate 120, so that the pins 28 can effectively support the first support 21 via the carrier plate 120. It is expected that embodiments of the invention will facilitate replacement of the first support 21. It is expected that embodiments of the invention will reduce downtime of the lithographic apparatus. It is not essential that the carrier plate 120 is provided. In an alternative embodiment (described in more detail below), alternatives to the pins 28 are provided to control the movement of the first support 21.

[0109] As the first support 21 and the carrier plate 120 are coupled together, the pins 28 may be controlled to lower the first support 21 onto the remainder of the substrate support 20. Once the first support 21 is placed onto the remainder of the substrate support 20, the carrier plate 120 may be removed. FIG. 16 shows the carrier plate 120 being detached and removed from the first support 21. In an embodiment, positive pressure is applied through the openings 44 to release the carrier plate 120 from the first support 21. The carrier plate 120 may be lifted off the first support 21 by the pins 28. In an embodiment, the carrier plate 120 may be driven using the same handling tool used to handle the substrate W.

[0110] As shown in FIG. 14 to FIG. 16, in one embodiment, the carrier plate 120 includes a plurality of connecting protrusions 122. The connecting protrusions 122 are configured to protrude from a base plate 125 of the carrier plate 120 toward the first support 21. The carrier plate 120 includes a base plate 125 and connecting protrusions 122. The base plate 125 is flat. In one embodiment, the base plate 125 and the connecting protrusions 122 are formed of the same material. To form the carrier plate 120, the base plate 125 is integrally formed with the connecting protrusions 122. As shown in FIG. 14, in one embodiment, the connecting protrusions 122 limit the distance that the base plate 125 can approach the first support 21. As shown in FIG. 14, in one embodiment, the connecting protrusions 122 have a contact surface 123. The contact surface 123 is configured to contact the first support 21 directly or via an adhesive material.

[0111] By providing the connecting protrusions 122, the ends of the burls 41 do not contact the carrier plate 120. The carrier plate 120 is supported by the first support 21 between the burls 41 on the upper side of the first support 21, with the ends of the burls 41 on the upper side of the first support 21 being isolated from the carrier plate 120. It is expected that the embodiments of the invention will further prevent wear of the burls 41.

[0112] 17 is a schematic diagram of a carrier plate 120 according to an embodiment of the invention. As shown in FIG. 17, in one embodiment, the surface of the carrier plate 120 facing the first support 21 is sufficiently flat, and when the carrier plate 120 is bonded to the first support 21, the carrier plate 120 is supported by the ends of the burls 41 on the upper side of the first support 21. As shown in FIG. 17, in one embodiment, the connection protrusions 122 do not limit the distance that the carrier plate 120 can approach the first support 21. Instead, the ends of the burls 41 support the carrier plate 120. The ends of the burls 41 contact the base plate surface 124 directly or via an adhesive material.

[0113] 14 and 15, in one embodiment, only a portion of the carrier plate 120 contacts the first support 21. This limits adhesion forces and facilitates separation of the carrier plate 120 and the first support 21.

[0114] 17 and 19, for example, it is not necessary for the carrier plate 120 to contact the surface of the first support 21 between the burls 41. In one embodiment, the surface between the burls 41 is rough so that adhesion forces are limited. By not requiring contact with the rough surface between the burls 41, the rough surface does not adversely affect the carrier plate 120 being bonded to the first support 21.

[0115] In the arrangement shown in Fig. 17, the ends of the burls 41 contact the carrier plate 120. One of the reasons why the first support 21 is replaced is because the burls may become worn. If replacement of the first support 21 is necessary, the ends of the burls 41 may be particularly smooth. The ends of the burls 41 allow suitable adhesion to the carrier plate 120, particularly for removing the first support 21.

[0116] The manner in which the carrier plate 120 is bonded to the first support 21 is not particularly limited. Fig. 18 illustrates the use of an adhesive material 126 for bonding the carrier plate 120 to the first support 21. As illustrated in Fig. 18, in one embodiment, the adhesive material 126 is provided between the first support 21 and the contact surface 123 of the connecting protrusion 122. Additionally or alternatively, the adhesive material 126 may be provided between the ends of the multiple burls 41 and the base plate surface 124.

[0117] The adhesive material 126 is for temporarily adhering the carrier plate 120 to the first support 21 when the carrier plate 120 is bonded to the first support 21. The adhesive material 126 is not particularly limited. In one embodiment, the adhesive material (bonding material) 126 comprises an adhesive material. In an alternative embodiment, a layer of liquid (e.g., water) is provided in place of the adhesive material 126. Capillary pressure may be used to maintain the bond between the carrier plate 120 and the first support 21.

[0118] 17, the adhesive material may be applied to recesses in the base plate surface 124. By confining the adhesive material to the recesses, the likelihood of the adhesive material coming into contact with other components is reduced.

[0119] As shown in Fig. 19, in addition or alternatively, the carrier plate 120 is clamped to the first support 21 by pressure. In one embodiment, the carrier plate 120 comprises at least one internal channel 127 for fluidly connecting the first opening 128 to at least one second opening 129. The first opening 128 and the second opening 129 are in a surface of the carrier plate 120. As shown in Fig. 19, in one embodiment, the first opening 128 is in a position where the carrier plate 120 covers one of the pinholes 121 when the carrier plate 120 is coupled to the first support 21.

[0120] The second opening 129 is located where the carrier plate 120 faces the top side of the first support 21. In one embodiment, the first opening 128 can be connected to a negative pressure to generate a gas flow from the second opening 129 through the internal channel 127 to the first opening 128 and out through the first opening 128. This can reduce the pressure in the area between the carrier plate 120 and the first support 21 when the carrier plate 120 is coupled to the first support 21. As a result of the surrounding pressure being higher than the pressure between the carrier plate 120 and the first support 21, the carrier plate 120 and the first support 21 can be held together.

[0121] 19, in one embodiment, there are first openings 128 at positions corresponding to the pins 28 supporting the carrier plate 120. In one embodiment, the pins 28 include channels for taking fluid from the internal channels 127 through the first openings 128. The number of second openings 129 is not particularly limited. The number of internal channels 127 is not particularly limited. In one embodiment, a first opening 128 is provided for each pinhole 121.

[0122] In one embodiment, the carrier plate 120 comprises a conductive material and an insulating layer configured to electrically insulate the conductive material from the first support 21 when the carrier plate 120 is connected to the first support 21. The conductive material may have a potential difference with respect to the first support 21. Electrostatic attraction between the carrier plate 120 and the first support 21 may aid in bonding the carrier plate 120 to the first support 21. In one embodiment, the insulating layer is provided as a thin layer surrounding the carrier plate 120.

[0123] 20 to 22 show different stages of the carrier plate 120 being released from the first support 21 according to an embodiment of the invention. As shown in FIG. 20, in one embodiment, the carrier plate 120 comprises at least one connection mechanism 151. The connection mechanism 151 is configured to mechanically lock the carrier plate 120 to the first support 21. In one embodiment, the connection mechanism 151 locks the carrier plate 120 to the first support 21 at each pinhole 121 of the first support 21.

[0124] 20 , in one embodiment, the connection mechanism 151 includes a chamber 153. The chamber 153 is configured to receive each pin 28. The chamber 153 receives a contact end of the pin 28 when the pin 28 supports the carrier plate 120. In one embodiment, the connection mechanism 151 is configured to release the lock when the pressure in the chamber 153 is sufficiently lower than the atmospheric pressure outside the chamber 153 such that the carrier plate 120 may be released from the first support 21. The carrier plate 120 may be released from the first support 21 when the lock is released.

[0125] As shown in FIG. 20 , in one embodiment, the connection mechanism 151 includes at least one locking element 152. The locking element 152 is configured to penetrate the pinhole 121 and engage with a surface of the first support 21 opposite the base plate 125 of the carrier plate 120. The number of locking elements 152 is not particularly limited. In one embodiment, two, three, four or more than four locking elements 152 are provided. The locking elements 152 may be uniformly distributed in a circumferential direction around the pinhole 121. In one embodiment, the locking elements 152 are substantially continuous in a circumferential direction along the inner peripheral surface of the pinhole 121. The locking element 152 is fixedly connected at one end to the base plate 125 of the carrier plate 120. In one embodiment, the locking element 152 is integrally formed with the base plate 125 of the carrier plate 120.

[0126] In one embodiment, the chamber 153 is connected to a negative pressure to reduce the pressure therein. When the carrier plate 120 is released from the first support 21, the chamber 153 is connected to a negative pressure. As mentioned above, in one embodiment, the pin 28 includes a channel for taking fluid from above the contact end of the pin 28. In one embodiment, the channel in the pin 28 is configured to take fluid from the chamber 153 to reduce the pressure therein. As shown in FIG. 20, in one embodiment, a plurality of pores 154 are provided for fluidly connecting the channels of the pin 28 to the chamber 153. The number and shape of the pores 154 are not particularly limited. In one embodiment, a mesh is provided with the pores 154. In one embodiment, the mesh is integrally formed with the base plate 125 of the carrier plate 120. In one embodiment, the contact end of the pin 28 is not completely perpendicular to the length of the pin 28 so that the channels in the pin 28 are fluidly connected to the chamber 153 when the pin 28 supports the carrier plate 120.

[0127] Figure 21 illustrates a process step in which the pressure in the chamber 153 is reduced. The reduced pressure in the chamber 153 results in the locking elements 152 bending inwardly towards the pins 28. This disengages the locking elements 152 from the surface of the first support 21 opposite the base plate 125 of the carrier plate 120. Once the locking elements 152 are disengaged from the first support 21, the carrier plate 120 is no longer locked to the first support 21. As shown in Figure 22, the carrier plate 120 can be released from the first support 21.

[0128] 23 to 25 show schematic diagrams of an alternative connection mechanism 151 according to an embodiment of the invention. As shown in FIG. 23, in one embodiment, the chamber 153 is defined by a housing 157. In one embodiment, a portion of the housing 157 protrudes from a surface of the carrier plate 120 opposite the first support 21. In one embodiment, the housing 157 is formed as a separate component from the base plate 125 and is later connected to the base plate 125. It is expected that the embodiment of the invention will facilitate the manufacture of the carrier plate 120. The design of the base plate 125 will be simpler.

[0129] In one embodiment, the material used for the housing 157 is different than the material used for the base plate 125 of the carrier plate 120. As shown in FIG. 23, in one embodiment, the locking element 152 is integrally formed with the housing 157 that defines the chamber 153.

[0130] 23, in one embodiment, the carrier plate 120 includes an unlocking channel portion 155. The unlocking channel portion 155 defines an unlocking channel through which fluid can flow to unlock the carrier plate 120 from the first support 21. As shown in FIG. 23, in one embodiment, the carrier plate 120 includes a resilient member 156 configured to connect a housing 157 to the unlocking channel portion 155. In one embodiment, the unlocking channel portion 155 is part of the base plate 125 of the carrier plate 120.

[0131] As shown in FIG. 24, in one embodiment, a channel in the pin 28 is connected to an unlocking channel in the unlocking channel portion 155. This allows the pressure in the chamber 153 to be reduced. When the pressure in the chamber 153 is reduced, the housing 157 is pulled downward relative to the base plate 125 of the carrier plate 120. As shown in FIG. 24, in one embodiment, the housing 157 includes a portion that is inclined relative to the surface of the base plate 125 such that the downward movement of the housing 157 relative to the base plate 125 bends the locking element 152. When the locking element 152 bends, the locking element 152 is disengaged from the first support 21. When the locking element 152 is disengaged from the first support 21, the carrier plate 120 is unlocked from the first support 21. When the pressure in the chamber 153 is reduced, the elastic member 156 can be compressed. Otherwise, as shown in Fig. 23, the elastic member 156 maintains the elevated position of the housing 157 relative to the base plate 125 of the carrier plate 120. When the carrier plate 120 is unlocked, as shown in Fig. 25, the carrier plate 120 can be released from the first support 21.

[0132] It is not essential that the carrier plate 120 is provided. FIG. 26 is a schematic plan view of the first support 21 according to an embodiment of the invention. As shown in FIG. 26, in one embodiment, the carrier plate 120 is not provided. As a result, the pins 28 extend freely through each pinhole 121. In one embodiment, the pins 28 are not used to lower the first support 21 onto the body 22 of the substrate support 20. In one embodiment, an additional set of pins 160 is provided at a different position than the pins 28 used to lower the substrate W. The profile of the top of the pins 160 is shown in FIG. 26. In one embodiment, an additional set of pinholes for the pins 160 to pass through is provided in a portion of the substrate support 20 lower than the first support 21. For example, such an additional set of pinholes is provided in the body 22. The pins 160 pass through an additional set of pinholes in the body 22 and support the lower surface of the first support 21. On the other hand, the pins 28 for supporting the substrate W pass through pinholes 121 that pass through both the main body 22 and the first support 21 .

[0133] In an alternative embodiment, the pins 28 used to lower the substrate W support the first support 21 when the first support 21 is at a different rotational position than the target position on the body 22. The first support 21 can be supported by the pins 28 and lowered onto the body 22 in its rotational direction. The carrier plate 120 is not required because the pin holes 121 through the first support 21 do not align with the pins 28. This is because the first support 21 has rotated relative to its final target position. Once the first support 21 is supported by the body 22, the first support 21 is rotated to reach the target rotational position on the body 22. Once the first support 21 is at the target position on the body 22, the pin holes 121 are aligned between the first support 21 and the body 22 so that the pins 28 can pass through the pin holes 121 to support the substrate W above the first support 21. In one embodiment, a rotation tool is provided to rotate the first support 21 on the body 22. By rotating the first support 21 supported by the body 22 , there is no need to provide a carrier plate 120 and there is no need to provide a separate set of pins 160 .

[0134] FIG. 27 is a schematic plan view of a first support 21 according to an embodiment of the invention. As shown in FIG. 27, the first support 21 is gripped for handling. As shown in FIG. 27, in one embodiment, a plurality of edge grippers 161 are provided to grip the first support 21. The edge grippers 161 are configured to grip the outer edge of the first support 21. In one embodiment, the edge grippers 161 are configured in a handling tool separate from the handling tool for handling the first support 21. By providing a separate handling tool, there is no need to use pins 28 for lowering the first support 21 and no need to provide a carrier plate 120.

[0135] FIG. 28 is a schematic plan view of the first support 21 according to an embodiment of the invention. As shown in FIG. 28, the first support 21 is gripped for handling. As shown in FIG. 28, in one embodiment, an upper gripper 162 is provided to grip the upper part of the first support 21. By providing the upper gripper 162, there is no need to provide a different set of pins 160 for handling the carrier plate 120 or the support 21. In one embodiment, the upper gripper 162 is configured in a handling tool separate from the handling tool for handling the first support 21. The separate handling tool is separated from the pins 28 used to lower the substrate W onto the first support 21.

[0136] The features shown in the different embodiments illustrated in the figures may be combined with one another, unless a lack of compatibility is evident. By way of example only, the feature of providing burls 47 on the underside of the first support 21 (shown in figure 8) may be applied to the arrangements shown in figures 5, 9, 10 or 11. In particular, the arrangement shown in figure 9 may be modified by replacing the burls 65 on the upper side of the body 22 with burls 47 provided on the underside of the first support 21. Other combinations of the features shown in the figures are possible as well.

Claims

1. A first support configured to support a substrate; a body separated from the first support and configured to support the first support, the body comprising a thermal conditioner configured to thermally condition the body, the first support, and / or the substrate; a removal body surrounding the body and the first support, the removal body including a first removal channel configured to remove fluid from near a periphery of the substrate; Equipped with 1. A substrate support for supporting a substrate in a lithographic apparatus, wherein the first support is configured to be removed from the body and repositioned on the body.

2. The substrate support of claim 1 , further comprising a second support separated from the body and configured to support the body on the substrate stage, the second support configured to reduce relative movement between the substrate support and the substrate stage.

3. the body includes a plurality of burls on an upper side thereof, the burls having ends in a plane configured to support the first support; or the first support includes a plurality of burls on an underside thereof having ends in a plane configured to contact an upper side of the body; A substrate support according to claim 1 or 2.

4. 4. The substrate support of claim 1 , further comprising a second outlet channel configured to extract fluid from radially inward of the first outlet channel, the second outlet channel configured to extract fluid from below the peripheral edge of the substrate, preventing liquid from reaching the space between the center of the substrate and the first support, and separated from the first outlet channel by an open gap.

5. A substrate support according to any preceding claim, wherein an open gap or channel is formed between the ejection body, the body and the first support, or the ejection body is integrally formed with the body.

6. The substrate support of claim 5, wherein an open gap or flow passage provides fluid communication between atmospheric pressure or a pressure source, and / or the body extends below the eluent body, the underside of the eluent body being bonded to the body, and an adhesive layer being provided between the eluent body and the body.

7. A substrate support as described in any one of claims 1 to 6, wherein a thermal conditioner is mounted under the surface of the body and / or a pinhole configured to allow each pin for lowering the substrate onto the first support to pass through penetrates the first support in the thickness direction of the first support.

8. The substrate support of claim 7 , comprising a carrier plate configured to be coupleable and releasable to the first support, the carrier plate configured to cover the pinhole when coupled to the first support.

9. the first support includes a plurality of burls on an upper side thereof, the burls having ends in a plane configured to support a substrate; the carrier plate includes connecting projections configured such that the carrier plate is supported by the first support between the upper burls of the first support while ends of the upper burls of the first support are spaced from the carrier plate; or the first support includes a plurality of burls on an upper side thereof, the burls having ends in a plane configured to support a substrate; the surface of the carrier plate facing the first support is sufficiently flat, and when the carrier plate is joined to the first support, the ends of the burls on the upper side of the first support support the carrier plate; A substrate support according to claim 8.

10. 10. The substrate support of claim 8, further comprising: an adhesive material for temporarily adhering the carrier plate to the first support when the carrier plate is coupled to the first support; and / or the carrier plate comprises at least one internal channel for fluidly connecting the first opening to at least one second opening, the first opening being at a position where the carrier plate covers one of the pinholes when the carrier plate is coupled to the first support and the second opening being at a position where the carrier plate faces an upper side of the first support; and / or the carrier plate comprises a conductive material and an insulating layer configured to electrically insulate the conductive material from the first support when the carrier plate is coupled to the first support; and / or the carrier plate comprises at least one connection mechanism configured to mechanically lock the carrier plate to each pinhole of the first support.

11. The substrate support of claim 10, wherein the connection mechanism comprises a chamber configured to receive each pin, and the connection mechanism is configured to release the lock when the pressure in the chamber is sufficiently lower than atmospheric pressure outside the chamber so that the carrier plate can be released from the first support.

12. A substrate stage; 7. The substrate support according to claim 1, wherein the take-out body is provided on the substrate stage, or the substrate support according to claim 5 or 6, wherein the lower side of the take-out body is attached to the substrate stage; A substrate table comprising:

13. 13. A substrate table according to claim 12, comprising a height adjustment mechanism configured to control the height of at least a portion of the extractor below the substrate, such that the extractor is configured to prevent liquid from reaching between a centre of the substrate and the first support.

14. the height adjustment mechanism comprises an insert member between an underside of the ejection body and the substrate stage, and a fastener configured to couple the ejection body to the insert member; the insert member is configured with a notch such that the insert member is compressed when the fastener couples the ejection body to the insert member to control the height of the ejection body below the substrate; or the ejection body comprises a leaf spring having a lower portion secured to a remainder of the ejection body and an upper portion extending between the ejection body and the first support; the height adjustment mechanism is configured to control the height of the top portion below the substrate such that the top portion is configured to prevent liquid from reaching between a center of the substrate and the first support; A substrate table according to claim 13.

15. A lithographic apparatus comprising a substrate support according to any of claims 1 to 12 or a substrate table according to claim 12, 13 or 14.

Images