Substrate support and lithography equipment

Abstract

A substrate support configured to support a substrate comprises an upper component, a core component, and a lower component. A first opening is formed on the upper surface of the upper component, a first passage communicating with the first opening is defined in the upper component and the core component, a first extraction channel communicating with the first passage is defined by the core component and the lower component, and a first adjustment channel is defined by the core component and the lower component.

Description

Technical Field

[0001] (Cross - reference to related applications)

[0001] This application claims the priority of European Patent Application No. 23161486.8 filed on March 13, 2023 and European Patent Application No. 23200625.4 filed on September 28, 2023. These applications are hereby incorporated by reference in their entirety into this application.

[0002]

[0002] The present invention relates to a substrate support configured to support a substrate, a lithographic apparatus including the substrate support, a method of supporting a substrate, and a method of manufacturing a device including the method of supporting a substrate.

Background Art

[0003]

[0003] A lithographic apparatus is a machine configured to apply a desired pattern onto a substrate. A lithographic apparatus can be used, for example, in the manufacture of integrated circuits (ICs). A lithographic apparatus can project, for example, using a projection system, a pattern of a patterning device (e.g., a mask) (often referred to as a "design layout" or "design") onto a layer of radiation - sensitive material (resist) provided on a substrate (e.g., a wafer). Known lithographic apparatuses include so - called steppers in which each target portion is irradiated by exposing the entire pattern once to the target portion, and so - called scanners in which each target portion is irradiated by scanning the pattern in this direction with a radiation beam while synchronously scanning the substrate in a given direction (the "scan" direction) parallel or antiparallel thereto.

[0004]

[0004] As semiconductor manufacturing processes continue to advance, the dimensions of circuit elements have continuously decreased, while the number of functional elements such as transistors per device has steadily increased over decades, following a trend commonly known as Moore's Law. To keep up with Moore's Law, the semiconductor industry is pursuing technologies that enable the creation of increasingly smaller features. To project patterns onto a substrate, lithography equipment can use electromagnetic radiation. The wavelength of this radiation determines the minimum size of the feature 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]

[0005] Further improvement in the resolution of smaller features can be achieved by providing an immersion fluid with a relatively high refractive index, such as water, on the substrate during exposure. The effect of the immersion fluid is that it enables imaging of smaller features, as exposure radiation has shorter wavelengths in the immersion fluid than in the gas. The effect of the immersion fluid can also be thought of as increasing the effective numerical aperture (NA) and depth of field of the system.

[0006]

[0006] The immersion fluid can be confined to a local area between the projection system of the lithography apparatus and the substrate by the fluid handling structure. [Overview of the Initiative]

[0007]

[0007] In the semiconductor manufacturing process, the substrate is supported on a substrate support. Specifically, the substrate is supported on a plurality of burrs that protrude from the surface of the substrate support.

[0008]

[0008] In semiconductor manufacturing, there is an increasing trend to integrate more functions onto the unit surface of a substrate by reducing the size of the multilayer film layers on the substrate and increasing the number of multilayer film layers. As the number of layers stacked on the substrate increases, the stress induced between the film and the substrate increases, which can cause significant warping of the substrate and reduce overlay accuracy.

[0009]

[0009] A new configuration of substrate support has been proposed that includes additional features to prevent undesirable warping of the substrate support. Specifically, a new configuration of substrate support has been proposed that includes additional features to prevent undesirable warping of the substrate support when loading a substrate into the substrate support. The new configuration of substrate support may include additional openings to provide edge lifting force to the radially outer region of the substrate during loading.

[0010]

[0010] However, the additional openings and their positional requirements impose constraints on other features of the substrate support. These other features include supply channels that are in fluid communication with the openings, and regulating channels configured to maintain the substrate support at a constant temperature. If these supply and regulating channels are not optimally positioned within the substrate support, the temperature of the substrate support may change over time, potentially causing temporary structural deformation. Temporary structural deformation can lead to a decrease in the overlay accuracy of the lithography apparatus, including the substrate support.

[0011]

[0011] The object of the present invention is to provide a substrate support that enables additional functions to be implemented in the substrate support without causing a decrease in overlay accuracy due to temperature-induced structural deformation.

[0012]

[0012] According to the present invention, a substrate support is provided which is configured to support a substrate. The substrate support comprises an upper component, a core component, and a lower component. A first opening is formed on the upper surface of the upper component, a first passage communicating with the first opening is defined in the upper component and the core component, a first extraction channel communicating with the first passage is defined by the core component and the lower component, and a first adjustment channel is defined by the core component and the lower component.

[0013]

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

[0014]

[0014] Next, embodiments of the present invention will be described as merely examples with reference to the attached schematic drawings. In the drawings, corresponding reference symbols indicate corresponding parts.

[0015] [Figure 1] A schematic diagram of a lithography apparatus is shown. [Figure 2] A cross-sectional view shows a substrate support that does not conform to the present invention. [Figure 3] A cross-sectional view shows a portion of the circuit board support in a loaded state. [Figure 4] A cross-sectional view shows a portion of the clamped circuit board support. [Figure 5] A cross-sectional view shows a portion of the circuit board support in a bypass state. [Figure 6] A cross-sectional view shows a substrate support that does not conform to the present invention (i.e., a comparative example). [Figure 7] A cross-sectional view shows a part of the substrate support according to the present invention. [Figure 8] This is an isometric view of a substrate support according to the present invention, with the top removed so that the channel inside the substrate support is visible. [Figure 9] A plan view shows a portion of a substrate support according to the present invention, with the upper part removed so that the passage inside the substrate support is visible. [Figure 10] A cross-sectional view shows a portion of a substrate support including a "layered channel" configuration according to the present invention. [Figure 11] A cross-sectional view shows a portion of a substrate support that includes a "stacked channel" configuration different from the "stacked channel" configuration shown in Figure 10, according to the present invention. [Figure 12] A cross-sectional view shows a portion of a substrate support in which a control channel is in fluid communication with an extraction channel, according to the present invention. [Figure 13]A cross-sectional view of a part of a substrate support according to the present invention, where an extraction channel is in fluid communication with another extraction channel, is shown. [Figure 14] A cross-sectional view of a part of a substrate support according to the present invention, where an adjustment channel is in fluid communication with a fluid extraction recess, is shown. [Figure 15] A cross-sectional view of a part of a substrate support according to the present invention, where an adjustment channel is in fluid communication with an extraction channel, is shown. [Figure 16] A cross-sectional view of the radially outer portion of a substrate support according to the present invention is shown, showing a first fluid extraction groove. [Figures 17A-17B] A cross-sectional view of the radially outer portion of a substrate support according to the present invention, where a flow restriction member is provided in the first fluid extraction groove, is shown. [Figure 18] A plan view of a fluid extraction groove in which a plurality of flow restriction members are arranged is shown. [Figure 19] A cross-sectional view of the radially outer portion of a substrate support according to the present invention is shown, showing a first fluid extraction groove.

[0016] The features shown in the drawings are not necessarily to scale, and the sizes and / or arrangements shown are not limiting. It will be understood that the drawings may include optional features that may not be essential to the present invention. Also, not all features of the device are shown in each drawing, and only some of the components relevant to the description of a particular feature may be shown.

Mode for Carrying Out the Invention

[0017]

[0015] In this document, the terms "radiation" and "beam" are used to encompass all types of electromagnetic radiation including ultraviolet light (having wavelengths such as 365 nm, 248 nm, 193 nm, 157 nm, or 126 nm).

[0018]

[0016] The terms “reticle,” “mask,” or “patterning device” as used herein may be interpreted broadly to refer to a general-purpose patterning device that can be used to give an incoming radiation beam a patterned cross-section corresponding to a pattern created on a target portion of a substrate. The term “light bulb” can also be used in this context. In addition to classic masks (transmissive or reflective masks, binary masks, phase-shift masks, hybrid masks, etc.), other examples of such patterning devices include programmable mirror arrays and programmable LCD arrays.

[0019]

[0017] Figure 1 schematically illustrates a lithography apparatus. The lithography apparatus includes an illumination system (also called an illuminator) IL configured to adjust a radiation beam B (e.g., UV radiation or DUV radiation), a mask support (e.g., a mask table) MT constructed to support a patterning device (e.g., a mask) MA and connected to a first positioner PM configured to precisely position the patterning device MA according to specific parameters, a substrate support (e.g., a substrate table) WT constructed to hold a substrate (e.g., a resist-coated wafer) W and connected to a second positioner PW configured to precisely position the substrate support WT according to specific parameters, and a projection system (e.g., a refractive projection lens system) PS configured to project the pattern applied to the radiation beam B by the patterning device MA onto a target portion C of the substrate W (e.g., including one or more dies).

[0020]

[0018] During operation, the illumination system IL receives the radiated 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, such as refractive, reflective, magnetic, electromagnetic, electrostatic, and / or other types of optical components, or any combination thereof, for inducing, shaping, and / or controlling the radiation. The illuminator IL may be used to adjust the radiated beam B so that its cross-section has a desired spatial and angular intensity distribution in the plane of the patterning device MA.

[0021]

[0019] As used herein, the term “projection system” PS should be interpreted broadly to encompass various types of projection systems, including refractive optical systems, reflective optical systems, reflective-refractory optical systems, anamorphic optical systems, magneto-optical systems, electromagnetic optical systems, and / or electrostatic optical systems, or any combination thereof, as appropriate in accordance with the exposure radiation used and / or other factors such as the use of immersion liquid or vacuum. Where the term “projection lens” is used herein, it can be considered synonymous with the more general term “projection system” PS.

[0022]

[0020] The lithography apparatus is of a type in which at least a portion of the substrate W is covered with an immersion liquid having a relatively high refractive index, such as water, so as to fill the immersion space between the projection system PS and the substrate W, and this is also called immersion lithography. Further information on immersion technology is described in U.S. Patent No. 6,952,253, which is incorporated herein by reference.

[0023]

[0021] The lithography apparatus may be of a type that has two or more substrate support WTs (also called a “dual-stage”). In such a “multi-stage” machine, the substrate support WTs may be used in parallel, and / or, while a substrate W on one substrate support WT is being used to expose a pattern onto that substrate W, a preparation step for subsequent exposure of the substrate W may be performed on a substrate W located on another substrate support WT.

[0024]

[0022] In addition to the substrate support WT, the lithography apparatus may include a measurement stage (not shown in the drawings). The measurement stage is positioned to hold sensors and / or cleaning devices. The sensors may be positioned to measure the characteristics of the projection system PS or the characteristics of the radiating beam B. The measurement stage may hold multiple sensors. The cleaning devices may be positioned to clean parts of the lithography apparatus, such as a part of the projection system PS or a part of the system that provides the immersion fluid. The measurement stage may move below the projection system PS when the substrate support WT is away from the projection system PS.

[0025]

[0023] During operation, the radiating beam B is incident on a patterning device MA, such as a mask held on a mask support MT, and a pattern is formed by the pattern (design layout) present on the patterning device MA. The radiating beam B, having crossed the mask MA, passes through a projection system PS, which focuses the beam onto a target portion C of the substrate W. Using a second positioner PW and a position measuring system IF, the substrate support WT can be precisely moved to position various target portions C at focused and aligned positions within the path of the radiating beam B, for example. Similarly, a first positioner PM and optionally another position sensor (not explicitly shown in Figure 1) may be used to precisely position the patterning device MA relative to the path of the radiating beam B. The patterning device MA and the substrate W can be aligned using mask alignment marks M1, M2 and substrate alignment marks P1, P2. The illustrated substrate alignment marks P1, P2 occupy dedicated target portions, but may also be located in the space between target portions. When substrate alignment marks P1 and P2 are located between target portions C, they are called scribe line alignment marks.

[0026]

[0024] To clarify the present invention, the Cartesian coordinate system is used. The Cartesian coordinate system has three axes, namely the x-axis, y-axis, and z-axis. Each of the three axes is orthogonal to the other two axes. A rotation about the x-axis is called an Rx rotation. A rotation about the y-axis is called a Ry rotation. A rotation about the z-axis is called an Rz rotation. The x-axis and y-axis define the horizontal plane, while the z-axis is perpendicular. The Cartesian coordinate system is used only for clarification and not to limit the present invention. Alternatively, another coordinate system, such as a cylindrical coordinate system, may be used to clarify the present 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.

[0027]

[0025] Immersion technology has been introduced into lithography systems to enable improved resolution of smaller features. In an immersion lithography apparatus, a liquid layer of immersion fluid having a relatively high refractive index is interposed in the immersion space between the apparatus's projection system PS (the patterned beam is projected through the projection system PS toward the substrate W) and the substrate W. The immersion fluid covers at least the portion of the substrate W below the final element of the projection system PS. Thus, at least the portion of the substrate W to be exposed is immersed in the immersion fluid.

[0028]

[0026] In commercial immersion lithography, the immersion fluid is water. Typically, the water is highly purified distilled water, such as ultrapure water (UPW), which is commonly used in semiconductor manufacturing plants. In immersion systems, UPW is often purified and may undergo additional processing steps before being supplied to the immersion space as the immersion fluid. In addition to water, other liquids with a high refractive index, such as hydrocarbons including fluorinated hydrocarbons, and / or aqueous solutions, can be used as the immersion fluid. It is also conceivable that other fluids other than liquids may be used in immersion lithography.

[0029]

[0027] In this specification, local immersion refers to a situation in which, during use, the immersion fluid is confined to an immersion space between the final element and the surface facing the final element. This opposing surface is the surface of the substrate W, or the surface of a support stage (or substrate support WT) that is coplanar with the surface of the substrate W. (Note that, unless otherwise specified, when referring to the surface of the substrate W, the surface of the substrate support WT is also referred to, and vice versa.) A fluid handling structure IH located between the projection system PS and the substrate support WT is used to confine the immersion fluid to the immersion space. The immersion space, filled with the immersion fluid, is smaller than the top surface of the substrate W when viewed from above, and the immersion space remains substantially stationary relative to the projection system PS while the substrate W and substrate support WT move below.

[0030]

[0028] Other immersion systems are also envisioned, such as non-confined immersion systems (so-called "all-wet" immersion systems) and tank immersion systems. In non-confined immersion systems, the immersion liquid covers more than the surface beneath the final element. The liquid outside the immersion space exists as a thin liquid film. The liquid can cover the entire surface of the substrate W, or even the substrate W and the substrate support WT that is coplanar with the substrate W. In tank-type systems, the substrate W is completely immersed in a tank of immersion liquid.

[0031]

[0029] A fluid handling structure IH is a structure that supplies immersion fluid to an immersion space, removes immersion fluid from the immersion space, and thereby confines immersion fluid in the immersion space. It includes features that are part of a fluid supply system. A configuration disclosed in PCT Patent Application Publication WO99 / 49504 is an early fluid handling structure that includes a pipe that supplies or retrieves immersion fluid from the immersion space and operates in accordance with the relative motion of the stage below the projection system PS. In more recent designs, the fluid handling structure extends along at least a portion of the boundary of the immersion space between the final element of the projection system PS and the substrate support WT or substrate W so as to partially define the immersion space.

[0032]

[0030] The fluid handling structure IH may have a variety of functions. Each function may be derived from a corresponding feature that enables the fluid handling structure IH to achieve that function. The fluid handling structure IH may be referred to by several different terms, each referring to a single function, such as barrier members, sealing members, fluid supply systems, fluid removal systems, and liquid containment structures.

[0033]

[0031] The immersion liquid may be used as an immersion fluid. In that case, the fluid handling structure IH may be a liquid handling system. When referring to features defined in this paragraph in accordance with the preceding description, it can be understood that these features include features defined in relation to liquids.

[0034]

[0032] The lithography apparatus has a projection system PS. During exposure of the substrate W, the projection system PS projects a beam of patterned radiation onto the substrate W. To reach the substrate W, the path of the radiation beam B is 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 at the end of the beam path, which is in contact with the immersion liquid. This lens element in contact with the immersion liquid may be referred to as the "final lens element" or "final element". The final element is at least partially surrounded by the fluid handling structure IH. The fluid handling structure IH can confine the immersion liquid below and on the opposite surface of the final element.

[0035]

[0033] As shown in Figure 1, the lithography apparatus includes a controller 500. The controller 500 is configured to control the substrate table WT.

[0036]

[0034] Figure 2 shows a part of a lithography apparatus that does not conform to the present invention. The configuration shown in Figure 2 and described below can be applied to the lithography apparatus shown in Figure 1 and described above. Figure 2 is a cross-section of the substrate support 20 and the substrate W. In one embodiment, the substrate support 20 includes one or more adjustment channels 61 of a thermal adjustment system. A gap 5 exists between the edge of the substrate W and the edge of the substrate support 20. When the edge of the substrate W is imaged, or in other cases, such as when the substrate W first moves under the projection system PS (as described above), the immersion space, which is filled with liquid by the fluid handling structure IH (for example), passes at least partially over the gap 5 between the edge of the substrate W and the edge of the substrate support 20. As a result, liquid from the immersion space may enter the gap 5.

[0037]

[0035] The substrate W is held by a support body 21 (e.g., a pimple or prick table) which includes one or more pry bars 41 (i.e., protrusions from the surface). The support body 21 is an example of an object holder. Another example of an object holder is a mask holder. The negative pressure applied between the substrate W and the substrate support 20 helps to ensure that the substrate W is held firmly in place. However, if immersion liquid enters between the substrate W and the support body 21, this can cause problems, especially when unloading the substrate W.

[0038]

[0036] To address the entry of immersion liquid into the gap 5, at least one drain 10, 12 is provided at the edge of the substrate W to remove the immersion liquid that enters the gap 5. In the example in Figure 2, two drains 10, 12 are illustrated, but there may be only one drain, or there may be three or more drains. In one embodiment, each of the drains 10, 12 is annular so as to surround the entire outer periphery of the substrate W.

[0039]

[0037] The primary function of the first drain 10 (located radially outward from the edge of the substrate W / support body 21) is to help prevent gas bubbles from entering the immersion space where the liquid of the fluid handling structure IH is present. Such bubbles may adversely affect imaging of the substrate W. The first drain 10 is present to help prevent gas in the gap 5 from escaping into the immersion space of the fluid handling structure IH. If gas were to escape into the immersion space, this could result in bubbles floating in the immersion space. Such bubbles, if present in the path of the projection beam, could 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 the recess of the substrate support 20 on which the substrate W is placed. The edge of the recess of the substrate support 20 may optionally be defined by a covering 101 which is separate from the support body 21 of the substrate support 20. In the x / y plane, the covering 101 may have a ring shape surrounding the outer edge of the substrate W. The first drain 10 mainly extracts gas and also extracts a very small amount of immersion liquid.

[0040]

[0038] A second drain 12 (located radially inward from the edge of the substrate W / support body 21) is provided to help prevent liquid flowing down the substrate W from the gap 5 from hindering the efficient release of the substrate W from the substrate table WT after imaging. By providing the second drain 12, problems that may arise due to liquid flowing down the substrate W are mitigated or eliminated.

[0041]

[0039] As shown in Figure 2, the lithography apparatus includes a first extraction channel 102 through which an immersion fluid containing a substantial two-phase flow passes. The first extraction channel 102 is formed within the support body 21 or as a separate component. The first and second drains 10, 12 are provided with openings 107, 117 and extraction channels 102, 113, respectively. The extraction channels 102, 113 are in fluid communication with openings 107, 117 via passages 103, 114.

[0042]

[0040] As shown in Figure 2, the covering 101 has an upper surface. This upper surface extends circumferentially around the substrate W on the support body 21. When the lithography apparatus is in use, the fluid handling structure IH moves relative to the substrate support 20. During this relative movement, the fluid handling structure IH moves across the gap 5 between the covering 101 and the substrate W. In one embodiment, this relative movement occurs as the substrate support 20 moves below the fluid handling structure IH. In an alternative embodiment, this relative movement occurs as the fluid handling structure IH moves above the substrate support 20. In yet another alternative embodiment, this relative movement is given by both the substrate support 20 moving below the fluid handling structure IH and the fluid handling structure IH moving above the substrate support 20. In the following description, the movement of the fluid handling structure IH is used to describe the relative movement of the fluid handling structure IH with respect to the substrate support 20.

[0043]

[0041] Figures 3 to 5 show a cross-sectional view of a part of the substrate support 200. This cross-section extends in the vertical (i.e., x / z) plane. Figures 3 to 5 show only the radially outer portion of the substrate support 200. In Figures 3 to 5, the radially outer direction is to the right.

[0044]

[0042] The substrate support 200 has additional openings configured to provide a function to mitigate problems such as warping when loading the substrate W onto the substrate support 200, without contributing to flatness drift of the substrate W or the substrate support 200. Flatness drift of the substrate W can occur when moisture moves radially inward in the region between the substrate W and the substrate support 200.

[0045]

[0043] The substrate support 200 includes a plurality of crowbars 241. The distal ends of the crowbars 241 form a surface on which the lower side of the substrate W is supported. The lower side of the substrate W is in contact with the distal ends of the crowbars 241. The crowbars 241 are located on the upper side of the substrate support 200.

[0046]

[0044] As shown in Figures 3 to 5, the substrate support 200 includes a plurality of seals 231, 232, 233, and 234. These seals 231, 232, 233, and 234 are circumferential rings protruding from the substrate support 200. There are at least four seals: an inner seal 234, an inner central seal 233 located radially outside the inner seal 234, a central seal 232 located radially outside the inner central seal 233, and an outer seal 231 located radially outside the central seal 232.

[0047]

[0045] Multiple seals 231, 232, 233, and 234 define multiple regions (or "recesses") between the substrate support 200 and the substrate W. The first fluid extraction recess 250 is a region extending circumferentially from the outer seal 231 radially outward from the substrate support 200. The second fluid extraction recess 251 is a region extending circumferentially from the substrate support 200 between the central seal 232 and the outer seal 231. The peripheral recess 252 is a region extending circumferentially from the substrate support 200 between the inner central seal 233 and the central seal 232. The multifunctional recess 253 is a region extending circumferentially from the substrate support 200 between the inner seal 234 and the inner central seal 233.

[0048]

[0046] As shown in Figures 3 to 5, the substrate support 200 further includes a plurality of openings 261, 262, and 263. These are the multifunctional opening 263 located between the inner seal 234 and the inner central seal 233 (in the multifunctional recess 253), the peripheral opening 262 located between the inner central seal 233 and the central seal 232 (in the peripheral recess 252), the first fluid extraction opening 260 located radially outward of the outer seal 231 (in the first fluid extraction recess 250), and the second fluid extraction opening 261 located between the central seal 232 and the outer seal 231 (in the second fluid extraction recess 251).

[0049]

[0047] The multifunctional opening 263 may be configured to supply gas to the multifunctional recess 253 and to extract gas from the multifunctional recess 253. However, the multifunctional opening 263 may be configured to supply gas only. The ambient opening 262 may be configured to communicate with ambient pressure and fluid. Ambient pressure can be supplied from the atmosphere or from another source in the system. The ambient opening 262 may also be configured to communicate with positive pressure (pressure higher than ambient pressure) and fluid. The ambient opening 262 may also be configured to communicate with negative pressure (pressure lower than ambient pressure) when the negative pressure is higher than the pressure in the clamped second fluid extraction recess 251. The second fluid extraction opening 261 is configured to extract fluid (most commonly liquid) from the second fluid extraction recess 251. The second fluid extraction opening 261 is an example of the second opening 117 of the substrate support 20 shown in Figure 2. The first fluid extraction opening 260 is configured to extract immersion fluid (most commonly gas in the form of bubbles) from the first fluid extraction recess 250. The first fluid extraction opening 260 is an example of the first opening 107 of the substrate support 20 shown in Figure 2.

[0050]

[0048] The radially inward region of the inner seal 234 is the clamp region 254. The substrate support may further include a clamp opening 264 radially inward of the inner seal 234 (of the clamp region 254) which is configured to extract gas from the clamp region 254.

[0051]

[0049] When loading the substrate W onto the substrate support 200, the substrate W is first received by a plurality of e-pins in an extended position (not shown). The e-pins are then retracted to lower the substrate W toward the substrate support 200. Once the underside of the substrate W is in contact with the plurality of crowbars 241, the e-pins are further retracted so that the substrate W is no longer in contact with the e-pins and is fully supported by the plurality of crowbars 241.

[0052]

[0050] In this "loaded state" (Figure 3), gas is supplied to the multifunctional recess 253 through the multifunctional opening 263 to increase the pressure inside the multifunctional recess 253. As a result, the pressure inside the multifunctional recess 253 becomes higher than the ambient pressure. Since the pressure inside the multifunctional recess 253 is higher than the pressure above the substrate W, an upward force is applied to the substrate W (i.e., away from the substrate support 200).

[0053]

[0051] The substrate support 200 is configured such that the multifunctional recess 253 is positioned near the edge of the substrate W. As a result, any upward force applied to the substrate W is applied to the edge region of the substrate W. For a substrate W with a diameter of 300 mm, the edge region may be the region where the distance to the center of the substrate W (i.e., the radial distance) is greater than 135 mm. Generally, the edge region may be the region where the distance to the center of the substrate W is greater than 45% of the diameter of the substrate W. When an upward force is applied to this region, the edge of the substrate W deforms upward. This ensures that during the loading of the substrate W, the outermost radial circumferential ring portion 242 of the crowbar is the last point of contact between the substrate support 200 and the substrate W. This may not be the case when an "umbrella-shaped" substrate W is loaded onto the substrate support 200. This reduces frictional variations between the outermost radial circumferential ring portion 242 of the crowbar and the underside of the substrate W, improving the load reproducibility of the substrate W.

[0054]

[0052] At a specific point, the substrate support 200 transitions from a loaded state to a "clamped" state.

[0055]

[0053] In the clamped state (Figure 4), the multifunctional opening 263 can extract gas from the multifunctional recess 253 so that a negative pressure is generated within the multifunctional recess 253. This means that, similar to the clamped area 254, a clamping force is applied to the lower part of the substrate W corresponding to the multifunctional recess 253. Alternatively, the multifunctional opening 263 may be closed so that it does not have fluid communication with ambient pressure, overpressure, or negative pressure.

[0056]

[0054] In the clamped state, the perimeter opening 262, the first fluid extraction opening 260, and the second fluid extraction opening 261 can be opened. That is, the perimeter opening 262 is in fluid communication with the ambient pressure, and the first fluid extraction opening 260 and the second fluid extraction opening 261 extract immersion fluid from the first fluid extraction recess 250 and the second fluid extraction recess 251, respectively. Alternatively, the perimeter opening 262 may be in fluid communication with a positive pressure source. Alternatively, the perimeter opening 262 may be in fluid communication with negative pressure (pressure lower than ambient pressure), which is the case when the negative pressure is higher than the pressure in the second fluid extraction recess 251. Figure 4 shows that when the substrate W is in the clamped state, the immersion fluid that flows through the gap 5 between the substrate W and the covering 201 may also pass between the outer seal 231 and the underside of the substrate W, and may be present in the first fluid extraction recess 250 and the second fluid extraction recess 251. The second fluid extraction opening 261 extracts this immersion fluid. The extraction pressure of the second fluid extraction opening 261, the central seal 232, and the ambient pressure within the surrounding recess 252 prevent the immersion fluid from flowing radially inward of the central seal 232.

[0057]

[0055] In the clamped state, the clamp opening 264 can continue to extract gas so as to increase the magnitude of the pressure difference between the clamped area 254 and the area above the substrate W. Alternatively, the clamp opening 264 may be closed to maintain a substantially constant pressure within the clamped area 254. Another alternative is to maintain a substantially constant pressure within the clamped area 254 by periodically extracting gas through the clamp opening 264.

[0058]

[0056] The substrate support 200 may also be configured to operate in a “bypass state” (see Figure 5), which is an alternative to the clamped state. In the bypass state, the clamp opening 264 and the multifunction opening 263 operate in the same way as in the clamped state. However, the periphery opening 262 can be closed. This means that the periphery opening 262, and therefore the periphery recess 252, are not in fluid communication with ambient pressure. Alternatively, the periphery opening 262 may remain open but be in fluid communication with a pressure source that is not sufficient to prevent the immersion fluid from flowing radially inward beyond the central seal 232. As a result, the immersion fluid surrounds the central seal 232 and the radially outermost circumferential ring portion 242 of the bar. In the bypass state, the multifunction opening 263 may be in fluid communication with a negative pressure source so that fluid can be extracted from the multifunction recess 253. In the alternative bypass state, the multifunctional opening 263 can supply ambient pressure or positive pressure to the multifunctional recess 253 to prevent the immersion fluid from flowing radially inward toward the clamping area 254 beyond the inner central seal 233. This situation, in which the outermost radial circumferential ring portion 242 of the crowbar is "wet," is sometimes preferable. This is because having a "wet" outermost radial circumferential ring portion 242 of the crowbar affects the friction between the distal end of the crowbar 242 and the underside of the substrate W.

[0059]

[0057] The force applied to the underside of the substrate W as a result of supplying gas to the multifunctional recess 253 in the loaded state is an edge lifting force. The edge lifting force is applied to the underside of the substrate W in the region corresponding to the multifunctional recess 253 between the inner seal 234 and the inner central seal 233. During the clamped state, atmospheric pressure or overpressure necessary to prevent the immersion fluid from flowing radially inward of the central seal 232 is supplied by the periphery opening 262. The inner central seal 233 is located between the multifunctional opening 263 and the periphery opening 262. This means that the magnitude of the edge lifting force depends on the distance between the inner seal 234 and the inner central seal 233. During the clamped state, fluid communication between the periphery recess 252 and the ambient pressure means that an upward force is applied to the substrate in the region corresponding to the periphery recess 252 (i.e., between the inner central seal 233 and the central seal 232). This can cause bumps in the flatness of the substrate W during the clamped state. The magnitude of the unevenness in the flatness depends on the distance between the inner central seal 233 and the central seal 232. As a result, the positions of seals 232, 233, and 234 and the positions of openings 262, 263 are constrained by the edge lifting requirement of the substrate support 200 and the flatness requirement of the substrate W.

[0060]

[0058] Taking this into consideration, the distance between the inner seal 234 and the inner central seal 233 can be made greater than the distance between the inner central seal 233 and the central seal 232, and the distance between the central seal 232 and the outer seal 231.

[0061]

[0059] In order to bring the multifunctional recess 253 close enough to the edge of the substrate W, the distance between the inner central seal 233 and the central seal 232, the distance between the central seal 232 and the outer seal 231, and the distance between the outer seal 231 and the circumferential edge of the substrate W are sufficiently small. In this context, "close enough" means close enough that the edge region of the substrate W deforms upward due to the edge-lifting force applied to the underside of the substrate W in the region corresponding to the multifunctional recess 253, and when the substrate support 200 is loaded, it can be ensured that the outermost radial circumferential ring portion 242 of the crowbar is the last point of contact with the underside of the substrate W.

[0062]

[0060] Preferably, the distance between the inner central seal 233 and the central seal 232 is configured such that the unevenness of the flatness of the substrate W between the inner central seal 233 and the central seal 232 is minimized when the substrate W is clamped to the substrate support 200.

[0063]

[0061] In order to ensure that the multifunctional recess 253 is sufficiently close to the edge of the substrate W, and to ensure the optimal flatness of the substrate W by balancing the bending moment acting on the substrate W, it is preferable that the distance between the center of the radial central seal 232 and the center of the radial outer seal 231 be small.

[0064]

[0062] Furthermore, in order to ensure that the multifunctional recess 253 is positioned sufficiently close to the circumferential edge of the substrate W, it is preferable that the distance between the outer seal 231 and the circumferential edge of the substrate W be small.

[0065]

[0063] The precise positioning of the seals 231, 232, 233, 234 and the openings 260, 261, 262, 263 is important to ensure that the additional functions provided by the openings 262, 263 are effectively implemented. Specifically, it is preferable to position the multifunctional opening 263 (and consequently the peripheral opening 262, the second fluid extraction opening 261, and the first fluid extraction opening 260) close to the edge of the substrate W so that the edge of the substrate W is deformed upward during loading, thereby avoiding umbrella-shaped deformation.

[0066]

[0064] However, in the current configuration of the substrate support 200, the positions of the openings 260, 261, 262, 263, and 264 are constrained by the positions of the channels within the body of the substrate support 200 that supply and / or receive fluid through the openings 260, 261, 262, and 263. The positions of the channels that supply and / or receive fluid through the openings 260, 261, 262, and 263, as well as the positions of the regulating channels, are constrained because they cannot overlap radially. The positions of the regulating channels themselves are constrained by the need for them to effectively regulate the temperature of the substrate support 200. A substrate support 200 that exhibits poor thermal performance (i.e., is unable to maintain a consistent temperature during use) may cause overlay errors in the lithography apparatus as a result of transient structural deformation caused by fluctuating temperatures. Thus, there are conflicting considerations: (i) positioning the openings to effectively provide the intended function, and (ii) positioning the channels so that the substrate support 200 exhibits acceptable thermal performance. The current configuration of the circuit board support can sometimes make it difficult to satisfy these conflicting considerations simultaneously.

[0067] <Comparative Example>

[0065] Figure 6 shows a cross-sectional view of a substrate support 300 that does not conform to the present invention. The cross-sectional view extends in the vertical (i.e., x / z plane). As with Figures 3 to 5, the radially outward direction is to the right in Figure 6. Only the radially outward portion of the substrate support 300 is shown. That is, the substrate support 300 continues to the left of the portion shown in Figure 6. The substrate support 300 may further include a plurality of crowbars (not shown), such as the crowbar 241 described with respect to Figures 3 to 5, on its upper surface.

[0068]

[0066] The substrate support 300 shown in Figure 6 performs the same function as the substrate support 200 shown in Figures 3 to 5. That is, the substrate support 300 includes a first extraction opening 360, a second extraction opening 361, a peripheral opening 362, and a multi-functional opening 363. The substrate support 300 may also include a clamp opening (equivalent to the clamp opening 264 of the substrate support 200 shown in Figures 3 to 5), which is not shown in Figure 6.

[0069]

[0067] The first extraction opening 360 is in fluid communication with the first extraction channel 380, the second extraction opening 361 is in fluid communication with the second extraction channel 381, the peripheral opening 362 is in fluid communication with the peripheral channel 382, ​​and the multifunctional opening 363 is in fluid communication with the multifunctional channel 383. The substrate support 300 may be configured such that each of these openings 360, 361, 362, and 363 provides the same function as the openings 260, 261, 262, and 263 described with respect to the substrate support 200 shown in Figures 3 to 5.

[0070]

[0068] The substrate support 300 further includes one or more regulating channels 391, 392, 393 of a thermal control system. The regulating channels act as heat sinks. Regulating fluid flowing through regulating channels 391, 392, 393 is maintained at a constant temperature. The temperature of the regulating fluid can be maintained at a desired temperature of the substrate support 300. Therefore, if the body of the substrate support 300 becomes higher or lower than the desired temperature (i.e., higher or lower than the temperature of the regulating fluid), heat is transferred to or from the regulating fluid, and the temperature of the body of the substrate support 300 returns to the desired value. Components that maintain the regulating fluid at a constant temperature may be located in a position within the lithography apparatus other than the substrate support 300.

[0071]

[0069] The substrate support 300 is formed of a first component 310 and a second component 311. In the horizontal (i.e., x / y) plane, the first component 310 and the second component 311 may each have the same shape as the substrate support 300 as a whole. That is, if the substrate support 300 has a circular shape in the horizontal plane, then the first component 310 and the second component 311 will each have a circular shape in the horizontal plane.

[0072]

[0070] The first component 310 is joined to the second component 311. This can be done by positioning the second component 311 on top of the first component 310. That is, the upper surface of the first component 310 can be joined to the lower surface of the second component 311. In this configuration, it may be the upper surface of the second component 311 that is configured to support the substrate W. Thus, it can be said that the substrate support 300 is formed of two layers, with the lower layer being the first component 310 and the upper layer being the second component 311.

[0073]

[0071] Channels 380, 381, 382, ​​383 and adjustment channels 391, 392, 393 can each be formed at the interface between the first component 310 and the second component 311. That is, channels 380, 381, 382, ​​383 and adjustment channels 391, 392, 393 can each be formed at a position where the upper surface of the first component 310 is joined to the lower surface of the second component 311. This means that channels 380, 381, 382, ​​383 and adjustment channels 391, 392, 393 can be formed using a standard removal manufacturing process.

[0074]

[0072] The configuration shown in Figure 6 has many drawbacks. As mentioned above, the positions of the openings 360, 361, 362, and 363 are constrained by the requirements of the functions they provide. However, the positions of the openings 360, 361, 362, and 363 are also constrained by the positions of the channels 380, 381, 382, ​​and 383 through which they communicate. The positions of the channels 380, 381, 382, ​​and 383 are constrained because they cannot overlap radially. In practice, it is preferable that there is a certain distance between the channels 380, 381, 382, ​​and 383 to ensure that they do not impair the structural integrity of the substrate support 300. The positions of the channels 380, 381, 382, ​​and 383 are further constrained by considerations related to the thermal performance of the substrate support 300.

[0075]

[0073] In the comparative example shown in Figure 6, in order to position the openings 361, 362, 363 and the associated channels 381, 383 in the desired locations, the passages 371, 373 connecting the openings 361, 363 to their respective channels 381, 383 are inclined so as not to be longitudinal (i.e., not perpendicular to the upper surface of the second component 311). Manufacturing holes at such inclination angles is more complex than manufacturing longitudinal holes (i.e., holes extending perpendicular to the surface being formed). Furthermore, the inclination angles at which holes can be manufactured may be limited. This means that, depending on the constraints on the position of the openings 361, 363 and their respective channels 381, 383, the inclined passages 371, 373 may not be feasible as a means of fluid communication between the openings 361, 363 and the channels 381, 383.

[0076]

[0074] In order to improve the thermal performance of the substrate support 300 (i.e., to ensure that the entire substrate support 300 can be maintained at a desired temperature), it may be preferable to position one of the adjustment channels 391, 392, and 393, for example, adjustment channel 391, in close proximity to the first extraction channel 380 and the second extraction channel 381. For example, it may be preferable to position the first adjustment channel 391 radially outward from the surrounding channel 382 and the multifunctional channel 383, but radially inward from the first extraction channel 380 and the second extraction channel 381. This is because the first extraction channel 380 and the second extraction channel 381 may contain liquid such as immersion fluid. If this liquid evaporates, a significant thermal load will act on the first extraction channel 380 and the second extraction channel 381. However, in the configuration shown in Figure 6, there is insufficient space available between the second extraction channel 381 and the surrounding channel 382 to place the first adjustment channel 391 between the second extraction channel 381 and the surrounding channel 382.

[0077] <This invention>

[0075] Figure 7 shows a cross-sectional view of a substrate support 200 according to the present invention. The cross-sectional view extends inward vertically (i.e., in the x / z plane). As with Figures 3 to 5, the radially outward direction is to the right. Only the radially outward portion of the substrate support 200 is shown. That is, the substrate support 200 continues to the left of the shown portion. For illustrative purposes, the substrate support 200 includes the same openings 260, 261, 262, 263 and functions as the substrate support 200 shown in Figures 3 to 5. However, the present invention is not limited to being implemented within a substrate support 200 having such functions. That is, the substrate support 200 according to the present invention does not necessarily include each of the openings 260, 261, 262, 263 and seals 231, 232, 233 included in the substrate support 200 shown in Figures 3 to 5.

[0078]

[0076] The substrate support 200 shown in Figure 7 is formed of three components, namely a lower component 210, a core component 211, and an upper component 212. However, the present invention is not limited to a configuration comprising only three components 210, 211, and 212, and a substrate support 200 according to the present invention may include more components. For example, a substrate support 200 according to the present invention may include four, five, or more components.

[0079]

[0077] In the horizontal (i.e., x / y) plane, the lower component 210, the core component 211, and the upper component 212 may each have the same shape as the substrate support 200 as a whole. That is, if the substrate support 200 has a circular shape in the horizontal plane, the lower component 210, the core component 211, and the upper component 212 will each have a circular shape in the horizontal plane.

[0080]

[0078] The lower component 210, the core component 211, and the upper component 212 are joined to each other. In the substrate support 200 shown in Figure 7, the lower component 210 is joined to the core component 211, and the core component 211 is joined to the upper component 212. Specifically, the upper surface of the lower component 210 is joined to the lower surface of the core component 211, and the upper surface of the core component 211 is joined to the lower surface of the upper component 212. Therefore, it can be said that the substrate support 200 shown in Figure 7 is formed of three layers, with the lower layer being the lower component 210, the middle layer being the core component 211, and the upper layer being the upper component 212.

[0081]

[0079] The means for joining these components to each other are not particularly limited. The joining method is preferably such that it allows for effective heat transfer between the lower component 210 and the core component 211, and between the core component 211 and the upper component 212. This is preferred because the features within the substrate support 200 that are responsible for regulating the temperature of the substrate support 200 can effectively perform temperature regulation. For example, if the regulating channels 291, 292, and 293 are formed mainly in one of the components, for example in the core component 211, the ability of these channels to regulate the temperature of the substrate support 200 is not limited to the core component 211. This is because heat can be transferred from other components (i.e., the upper component 212 and the lower component 210) through the bonding layer to the regulating channels 291, 292, and 293 (or vice versa). As a result, the regulating channels 291, 292, and 293 can regulate the temperature of the entire substrate support 200.

[0082]

[0080] The substrate support 200 may further include a heater (not shown). Similar to the regulating channels 291, 292, and 293, even if the heater is contained within a single component, heat can be transferred through the bonding layer, so the ability of the heater to regulate the temperature of the substrate support 200 is not limited to this component.

[0083]

[0081] In addition to the requirement that the bonding technique enables effective heat transfer between components 210, 211, and 212, it is preferable that the bonding layer formed between components 210, 211, and 212 can withstand high temperatures. Specifically, it is preferable that the bonding layer formed between components 210, 211, and 212 can withstand the temperatures to which the substrate support 200 may be exposed in the manufacturing process performed after the components 210, 211, and 212 are bonded to each other. For example, if the manufacturing process of the substrate support 200 includes a diamond coating step after the components 210, 211, and 212 are bonded to each other, it is preferable that the bonding layer can withstand the temperatures required for the diamond coating process.

[0084]

[0082] Examples of joining techniques may include penetration joining and diffusion joining, which will be discussed in more detail below.

[0085]

[0083] Of the three components 210, 211, and 212 of the substrate support 200 shown in Figure 7, the upper component 212 may be configured to support the substrate W. That is, the upper surface of the upper component 210 may include openings 260, 261, 262, and 263, and may also include any seals 231, 232, 233, 234 and crowbars 241 as described in relation to the substrate support 200 in Figures 3 to 5.

[0086]

[0084] According to the present invention, the substrate support 200 includes a first extraction opening 260. The first extraction opening 260 is an example of a first opening. The first extraction opening 260 may be formed on the upper surface of the upper component 212. This first extraction opening 260 is in fluid communication with a first extraction channel 280. The first extraction opening 260 may be in fluid communication with the first extraction opening 280 via the first passage 270, such that the first extraction opening 260 is in direct communication with the first passage 270 and the first passage 270 is in direct communication with the first extraction channel 280. In this context, “direct communication” means that features are in communication without an intermediary, i.e., features are adjacent to each other.

[0087]

[0085] The first extraction channel 280 can be defined by the core component 211 and the lower component 210. Specifically, the first extraction channel 280 can be defined by the core component 211 and the lower component 210 such that the first extraction channel 280 is positioned at the interface between the core component 211 and the lower component 210. However, the exact way in which the first extraction channel 280 is positioned at the interface between the core component 211 and the lower component 210 is not particularly limited. In the configuration shown in Figure 7, the first extraction channel 280 is formed by a channel portion 280a in the core component 211 and a channel portion 280b in the lower component 210. The substrate support 200 is configured such that when the core component 211 is joined to the lower component 210, the channel portion 280a in the core component 211 aligns with the channel portion 280b in the lower component 210 to form the first extraction channel 280.

[0088]

[0086] The channel portions 280a and 280b can be recesses in components 211 and 210. For example, channel portion 280a can be a recess in the core component 211, and channel portion 280b can be a recess in the lower component 210. The channel portions 280a and 280b can be voids within components 211 and 210. Specifically, channel portions 280a and 280b can be open voids. The channel portions 280a and 280b can be cavities within components 211 and 210. Specifically, channel portions 280a and 280b can be open cavities within components 211 and 210. That is, if components 211 and 210 are not joined to each other, the channel portions 280a and 280b can be open to the environment around components 211 and 210. The channel portions 280a and 280b may be regions within components 211 and 210 where the material on which components 211 and 210 are formed is absent or has been removed. The channel portions 280a and 280b can be cut into the surfaces of components 211 and 210. For example, channel portion 280a may be cut into the lower surface of core component 211, and channel portion 280b may be cut into the upper surface of lower component 210. The channel portions 280a and 280b may be rectangular in shape. Alternatively, the channel portions 280a and 280b may be U-shaped. In general, the shape of the channel portions 280a and 280b is not particularly limited.

[0089]

[0087] In the substrate support 200 shown in Figure 7, the channel portion 280a in the core component 211 is significantly larger than the channel portion 280b in the lower component 210, so when the first extraction channel 280 is formed, most of the first extraction channel 280 is located within the core component 211. However, this is not always the case, and the channel 280a in the core component 211 may be the same size as the channel 280b in the lower component 210, or the channel 280a in the core component 211 may be smaller than the channel 280b in the lower component 210.

[0090]

[0088] In fact, the first extraction channel 280 is defined by both the lower component 210 and the core component 211, although sometimes only one of the lower component 210 or the core component 211 contains the channel portions 280a, 280b. For example, the first extraction channel 280 may be formed by the channel portion 280a in the core component 211, and the substrate support 200 may be configured such that when the core component 211 and the lower component 210 are joined, the upper surface of the lower component 210 seals the open end of the recessed portion (i.e., the channel portion 280a) of the core component 211 to completely form the first extraction channel 280. The fact that the first extraction channel 280 can be formed as described above may also apply to other channels in the substrate support 200, such as channels 281, 282, 283 and adjustment channels 291, 292, 293. The fact that the first extraction channel 280 can be formed as described above can also be applied to the horizontal portions of passages 271, 272, and 273.

[0091]

[0089] The first passage 270 may be defined within the upper component 212 and the core component 211. The first passage 270 may extend substantially longitudinally (i.e., substantially perpendicular to the top surface of the upper component 212) from the first extraction opening 260 of the upper component 212, through the thickness of the upper component 212, and through any bonding layer present between the core component 211 and the upper component 212 into the first extraction channel 280. However, the shape of the first passage is not particularly limited. For example, the first passage 270 may be L-shaped, as described with reference to passages 271, 272, and 273.

[0092]

[0090] The substrate support 200 may further include a second extraction opening 261. The second extraction opening 261 is an example of a second opening. The second extraction opening 261 may be formed on the upper surface of the upper component 212. The second extraction opening 261 may be in fluid communication with a second extraction channel 281. A second passage 271 may be positioned between the second extraction opening 261 and the second extraction channel 281 so that the second extraction opening 261 and the second extraction channel 281 are in fluid communication. Specifically, the second extraction opening 261 may be in direct communication with the second passage 271, and the second passage may be in direct communication with the second extraction channel 261.

[0093]

[0091] The second extraction opening 261 can be positioned radially inward of the first extraction opening 260. The second extraction channel 281 can be positioned radially inward of the first extraction channel 280.

[0094]

[0092] The second passage 271 may be defined by the upper component 212 and the core component 211. The second passage 271 may be substantially L-shaped. That is, the second passage 271 may include a first vertical portion that extends substantially perpendicular to the upper surface of the upper component 212 and communicates directly with the second extraction opening 261. The second passage 271 may further include a horizontal portion that extends substantially parallel to the upper surface of the upper component 212 and communicates directly with the first vertical portion of the second passage 271. The vertical and horizontal portions of the second passage 271 may be substantially L-shaped. The second passage 271 may further include a second vertical portion that extends substantially perpendicular to the upper surface of the upper component 212 and communicates directly with the second extraction channel 281.

[0095]

[0093] Since the second extraction channel 281 may be positioned radially outward of the second extraction opening 261, the fluid flowing through the horizontal portion of the second passage 271 in the direction from the second extraction opening 261 to the second extraction channel 281 moves radially outward.

[0096]

[0094] The substrate support 200 may further include a first adjustment channel 291. The first adjustment channel 291 may be located radially inward of the first extraction channel 280 and the second extraction channel 281. If the second extraction channel 281 is not present, the first adjustment channel 291 may be located radially inward of the first extraction channel 280. The first extraction channel 280 and the second extraction channel 281 are known to be subjected to significant thermal loads. This is because the first extraction channel 280 and the second extraction channel 281 may contain a two-phase fluid. For example, if the substrate support 200 is configured for use in immersion lithography, the first extraction channel 280 and the second extraction channel 281 may contain the immersion fluid. This liquid evaporates within channels 280 and 281, creating an evaporation load (i.e., a thermal load) at the walls of the first and second extraction channels 280 and 281, which may be transmitted to the body of the substrate support 200. For this reason, it is preferable to position the first adjustment channel 291 close to the first and second extraction channels 280 and 281 so that the evaporation load in the first and second extraction channels 280 and 281 can be effectively reduced by the first adjustment channel 291. Furthermore, since the first adjustment channel 291 is positioned radially inward from the first and second extraction channels 280 and 281, the evaporation heat load from the first and second extraction channels 280 and 281 cannot be transmitted radially inward toward the center of the substrate support 200. As a result, the extent to which the thermal load generated in the first and second extraction channels 280 and 281 can adversely affect the flatness of the substrate support 200 is limited.

[0097]

[0095] The radial distance between the radially inner wall of the second extraction channel 281 and the radially outer wall of the first adjustment channel 291 may be less than 5 mm, preferably less than 2 mm, and more preferably less than 1.6 mm. The radial distance between the radially inner wall of the second extraction channel 281 and the radially outer wall of the first adjustment channel 291 may be greater than 1 mm, preferably greater than 1.4 mm. For example, the radial distance between the radially inner wall of the second extraction channel 281 and the radially outer wall of the first adjustment channel 291 may be greater than 1 mm and less than 5 mm, preferably greater than 1.4 mm and less than 2 mm, and more preferably greater than 1.4 mm and less than 1.6 mm. The radial distance between the radially inner wall of the second extraction channel 281 and the radially outer wall of the first adjustment channel 291 may be 1.5 mm. These distances ensure that the first adjustment channel 291 is close enough to the second extraction channel 281 and the first extraction channel 280 to effectively reduce the thermal load on the second extraction channel 281 and the first extraction channel 280, while ensuring that the wall thickness between the second extraction channel 281 and the first condition channel is sufficient to guarantee that the structural integrity of the substrate support 200 is not significantly impaired by the presence of channels 280, 281, and 291.

[0098]

[0096] The radial distance between the radially inner wall of the first extraction channel 280 and the radially outer wall of the second extraction channel 281 may be less than 5 mm, preferably less than 2 mm, and more preferably less than 1.6 mm. The radial distance between the radially inner wall of the first extraction channel 280 and the radially outer wall of the second extraction channel 281 may be greater than 1 mm, preferably greater than 1.4 mm. For example, the radial distance between the radially inner wall of the first extraction channel 280 and the radially outer wall of the second extraction channel 281 may be less than 5 mm and greater than 1 mm, preferably less than 2 mm and greater than 1.4 mm, and more preferably less than 1.6 mm and greater than 1.4 mm. These distances ensure that the openings 260, 261, 262, and 263 are positioned close enough to the edges of the substrate support 200, while ensuring that the wall thickness between the first extraction channel 280 and the second extraction channel 281 is sufficient to guarantee that the structural integrity of the substrate support 200 is not significantly impaired by the presence of the first and second extraction channels 280 and 281.

[0099]

[0097] The radial distance between the radial edge of the substrate support 200 and the radially outer wall of the first extraction channel 280 may be less than 5 mm, preferably less than 2 mm, and more preferably less than 1.5 mm. The radial distance between the radial edge of the substrate support 200 and the radially outer wall of the first extraction channel 280 may be greater than 1 mm, preferably greater than 1.3 mm. For example, the radial distance between the radial edge of the substrate support 200 and the radially outer wall of the first extraction channel 280 may be less than 5 mm and greater than 1 mm, preferably less than 2 mm and greater than 1.3 mm, and more preferably less than 1.5 mm and greater than 1.3 mm. These distances contribute to the first adjustment channel 291 being advantageously positioned radially outward. Furthermore, these distances ensure that the multiple channels 280, 281, 282, and 283 are favorably positioned in the edge region of the substrate support 200, thereby ensuring that the multiple openings 260, 261, 262, and 263 can be positioned close to the edge of the substrate W without requiring excessively long horizontal sections of the passages 271, 272, and 273 (i.e., these openings must be positioned to provide the necessary functions). The minimum distance is such that the thickness of the body of the substrate support 200 between the first extraction channel 280 and the edge of the substrate support 200 is sufficient to ensure that the structural integrity of the substrate support 200 is not significantly impaired by the presence of the first extraction channel 280.

[0100]

[0098] The width of the first extraction channel 280 (i.e., the radial distance between the radially outer wall and the radially inner wall of the first extraction channel 280) and the width of the second extraction channel 281 (i.e., the radial distance between the radially outer wall and the radially inner wall of the second extraction channel 281) will henceforth be referred to as the width of the extraction channels 280 and 281. This width may be less than 5 mm, preferably less than 2 mm, and more preferably less than 1.6 mm. The width of the extraction channels 280 and 281 may be greater than 1 mm, preferably greater than 1.4 mm. For example, the width of the extraction channels 280 and 281 may be less than 5 mm and greater than 1 mm, preferably less than 2 mm and greater than 1.4 mm, and more preferably less than 1.6 mm and greater than 1.4 mm. These dimensions ensure that the first adjustment channel 291 is favorably positioned radially outward, while ensuring that channels 280 and 281 are wide enough to effectively extract fluid from the area between the substrate W and the substrate support 200.

[0101]

[0099] The substrate support 200 may further include a peripheral opening 262. The peripheral opening 262 is an example of a fourth opening. The peripheral opening 262 may be formed on the upper surface of the upper component 212. The peripheral opening 262 may be in fluid communication with the peripheral channel 282. A fourth passage 272 may be positioned between the peripheral opening 262 and the peripheral channel 282. The fourth passage 272 may communicate directly with both the peripheral opening 262 and the peripheral channel 282 to facilitate fluid communication between the peripheral opening 262 and the peripheral channel 282.

[0102]

[0100] Similar to the second passage 271, the fourth passage 272 may be configured in an L-shape. That is, the fourth passage 272 may include a first vertical section that extends substantially perpendicular to the upper surface of the upper component 212 and communicates directly with the perimeter opening 262. The fourth passage 272 may further include a horizontal section that extends substantially parallel to the upper surface of the upper component 212 and communicates directly with the vertical section of the fourth passage 272. The fourth passage 272 may further include a second vertical section that communicates directly with the horizontal section of the fourth passage 272 and extends downward through the core component 211 in a substantially perpendicular direction to the upper surface of the upper component 212 and communicates directly with the perimeter channel 282.

[0103]

[0101] The peripheral channel 282 may be located radially inward of the first extraction channel 280, the second extraction channel 281, and the first adjustment channel 291. The peripheral opening 262 may be located radially inward of the second extraction opening 261 and the first extraction opening 260.

[0104]

[0102] The substrate support 200 may further include a multifunctional opening 263. The multifunctional opening 263 is an example of a third opening. The multifunctional opening 263 may be formed on the upper surface of the upper component 212. The multifunctional opening 263 may be in fluid communication with a multifunctional channel 283. The substrate support 200 may further include a third passage 273 positioned between the multifunctional opening 263 and the multifunctional channel 283, so that the multifunctional opening 263 is in direct communication with the third passage 273 and the multifunctional channel 283, facilitating fluid communication between the multifunctional opening 263 and the multifunctional channel 283.

[0105]

[0103] Similar to the second passage 271 and the fourth passage 272, the third passage 273 may be L-shaped or V-shaped. That is, the third passage 273 may include a first vertical section that extends substantially perpendicular to the upper surface of the upper component 212 and communicates directly with the multifunctional opening 263. The third passage 273 may further include a horizontal section that extends substantially parallel to the upper surface of the upper component 212 and communicates directly with the first vertical section of the third passage 273. The third passage 273 may further include a second vertical section that communicates directly with the horizontal section of the third passage 273 and extends downward through the core component 211 in a substantially perpendicular direction to the upper surface of the upper component 212 and communicates directly with the multifunctional channel 283.

[0106]

[0104] The peripheral channel 282 may be positioned radially inward of the peripheral opening 262. The multifunctional channel 283 may be positioned radially inward of the multifunctional opening 263. Therefore, in the flow path extending from the peripheral opening 262 to the peripheral channel 282, the immersion fluid flowing through the horizontal portion of the fourth passage 272 moves radially inward, and in the flow path extending from the multifunctional opening 263 to the multifunctional channel 283, the immersion fluid flowing through the horizontal portion of the third passage 273 moves radially inward.

[0107]

[0105] The substrate support 200 may include a plurality of other adjustment channels 292, 293. For example, in the embodiment shown in Figure 7, the substrate support 200 includes a second adjustment channel 292 and a third adjustment channel 293.

[0108]

[0106] The perimeter channel 282 and the multifunctional channel 283 may be located radially inward of the first adjustment channel 291. The perimeter channel 282 and the multifunctional channel 283 may be located radially outward of the second adjustment channel 292. It may be preferable that the second adjustment channel 292 is not located radially outward of the perimeter channel 282 and the multifunctional channel 283. This is because if the second adjustment channel 292 is located radially outward of the perimeter channel 282 and the multifunctional channel 283, the radial distance between the perimeter channel 282 and the perimeter opening 262 and the radial distance between the multifunctional channel 283 and the multifunctional opening 263 will become excessively large. If the radial distance between the perimeter channel 282 and the perimeter opening 262 and the radial distance between the multifunctional channel 283 and the multifunctional opening 263 becomes excessively large, the flow resistance between each channel 282, 283 and openings 262, 263 may increase to an undesirable degree. This is caused by the additional length of the horizontal sections of the third passage 273 and the fourth passage 272. Furthermore, positioning the second adjustment channel 292 radially inward of the peripheral channel 282 and the multifunctional channel 283 means that thermal (heating or cooling) loads on the peripheral channel 282 or the multifunctional channel 283 cannot be transmitted radially inward toward the center of the substrate support 200.

[0109]

[0107] Alternatively, a second adjustment channel 292 may be placed between the peripheral channel 282 and the multifunctional channel 283. That is, the second adjustment channel 292 may be placed radially inward of the multifunctional channel 283 and radially outward of the peripheral channel 282. This may be preferable to ensure that the second adjustment channel 292 can effectively reduce the heat load generated in the peripheral channel 282 and the multifunctional channel 283.

[0110]

[0108] The multifunctional opening 263 may be positioned radially inward of the periphery opening 262. Conversely, the periphery channel 282 may be positioned radially inward of the multifunctional channel 283. That is, the radial arrangement of the multifunctional opening 263 and the periphery opening 262 can be opposite to the radial arrangement of the corresponding multifunctional channel 283 and the periphery channel 282. To make this possible, the horizontal portion of the fourth passage 272 can be made longer than the horizontal portion of the third passage 273.

[0111]

[0109] Channels 280, 281, 282, and 283 configured to supply or extract gas in the substrate support 200 may be subjected to stress depending on the pressure within channels 280, 281, 282, and 283. The stress on channels 280, 281, 282, and 283 may result in deformation of channels 280, 281, 282, and 283. Channels located radially inward may be more sensitive to pressure changes. That is, the amount of deformation that occurs in radially inward channels in response to a given pressure change may be greater than that that occurs in radially outward channels in response to the same pressure change. In the substrate support 200, the multifunctional channel 283 may experience larger pressure changes than the surrounding channel 282 during use. Therefore, in order to minimize deformation of the substrate support 200 during use, it is preferable to position the multifunctional channel 283 radially inward from the surrounding channel 282, as described above.

[0112]

[0110] As described above, it is preferable to position the first adjustment channel 291 radially outward from the surrounding channel 282 and the multi-function channel 283 so that the first adjustment channel 291 can be positioned in close proximity to the second extraction channel 281.

[0113]

[0111] Figure 8 shows a substrate support 200 according to the present invention. The diagram of the substrate support 200 in Figure 8 is a view of the substrate support 200 from above. The top of the substrate support 200 has been removed so that features within the core component 211, such as channels 280, 281, 282, 283 and adjustment channels 291, 292, 293, are visible.

[0114]

[0112] According to the present invention, channels 280, 281, 282, and 283 can be cavities within the substrate support 200. The cross-section of each channel 280, 281, 282, and 283 can be rectangular. As can be seen in Figure 8, each of channels 280, 281, 282, and 283 extends circumferentially around the entire circumference of the substrate support 200.

[0115]

[0113] Up to this point, the adjustment channels 291, 292, and 293 have been referred to as separate channels (i.e., the first adjustment channel 291, the second adjustment channel 292, and the third adjustment channel 293), but the substrate support 200 shown in Figure 8 has a single adjustment channel 290 with a helical configuration. That is, the adjustment channel 290 starts at a radially inward position. As the adjustment channel 290 extends along the circumference of the substrate support 200, the distance between the adjustment channel 290 and the center of the substrate support 200 increases. When such a helical configuration is implemented, a cross-section of the substrate support 200 as shown in Figure 7 shows separate adjustment channels 291, 292, and 293. For this reason, in the substrate support 200 shown in Figure 7, the first adjustment channel 291, the second adjustment channel 292, and the third adjustment channel 293 may be part of a single helical adjustment channel 290.

[0116]

[0114] The passages 270, 271, 272, and 273 may not extend in the circumferential direction of the substrate support 200. For example, the passages 270, 271, 272, and 273 may be holes. The holes may have a circular cross-section.

[0117]

[0115] Similar to the passages 270, 271, 272, and 273 through which the openings 260, 261, 262, and 263 communicate, the openings 260, 261, 262, and 263 may not extend in the circumferential direction of the substrate support 200. The openings 260, 261, 262, and 263 may have the same cross-section as the corresponding passages 270, 271, 272, and 273. For example, the openings 260, 261, 262, and 263 can be circular. Multiple openings 260, 261, 262, and 263 may be distributed in the circumferential direction of the substrate support 200. For example, there may be multiple multi-functional openings 263 distributed in the circumferential direction of the substrate support 200.

[0118]

[0116] Figure 9 shows a portion of the substrate support 200 according to the present invention. The portion of the substrate support 200 shown in Figure 9 is a view from above the substrate support 200. The top of the substrate support 200 has been removed so that features within the upper component 212, such as the horizontal sections of passages 270, 271, 272, and 273, are visible.

[0119]

[0117] As shown in Figure 9, passages 270, 271, 272, and 273 can be positioned at different circumferential locations. This is so that when the horizontal portions of passages 270, 271, 272, and 273 overlap radially (e.g., passages 272 and 273), the horizontal portions of the passages do not interfere with each other.

[0120]

[0118] When there are multiple openings 260, 261, 262, and 263, there may be passages 270, 271, 272, and 273 for each of the openings 260, 261, 262, and 263. For example, when there are multiple perimeter openings 262 (e.g., perimeter opening A, perimeter opening B, perimeter opening C, etc.), there may be a fourth passage 272 for each of the perimeter openings 262 (e.g., a fourth passage A272a corresponding to perimeter opening A, a fourth passage B272b corresponding to perimeter opening B, a fourth passage C273c corresponding to perimeter opening C, etc.).

[0121]

[0119] The horizontal portions of passages 270, 271, 272, and 273 may be located at the interface between the core component 211 and the upper component 212. In the embodiment shown in Figure 7, the horizontal portions of passages 270, 271, 272, and 273 are formed by passage portions within the upper component 212, and when the core component 211 is joined to the upper component 212, the core component 211 provides a closing surface so that the recess in the upper component 212 becomes the complete passages 271, 272, and 273. However, according to the present invention, the horizontal portions of passages 271, 272, and 273 may not be formed in this way. For example, each of the horizontal portions of passages 271, 272, and 273 may be formed by passage portions in both the upper component 212 and the core component 211, so that when the core component 211 is joined to the upper component 212, the passage portions can align to form passages 271, 272, and 273.

[0122]

[0120] The second extraction channel 281, the multi-function channel 283, and the peripheral channel 282 can all communicate with the fluid control unit 201. The first extraction channel 280 can also communicate with the fluid control unit 201, but this is not shown in Figure 7.

[0123]

[0121] Figure 10 shows another substrate support 400 according to the present invention. In the substrate support 400 shown in Figure 10, channels 480, 481, 482, and 483 are arranged in a stacked configuration. Except for the arrangement of channels 480, 481, 482, and 483, the substrate support 400 may have the same features as the substrate support 200 described above. That is, the substrate support 400 shown in Figure 10 includes a lower component 410, a core component 411, and an upper component 412. The substrate support 400 further includes channels 480, 481, 482, and 483, openings 461, 462, and 463, and passages 470, 471, 472, and 473.

[0124]

[0122] In the substrate support 200 shown in Figure 7, all channels 280, 281, 282, and 283 are formed at the interface between the lower component 210 and the core component 211. In the substrate support 400, the first extraction channel 480 and the peripheral channel 482 are formed at the interface between the lower component 410 and the core component 411, while the second extraction channel 481 and the multifunctional channel 483 are formed at the interface between the core component 411 and the upper component 412. As a result of this configuration, channels 480, 481, 482, and 483 can overlap radially without physically interfering with each other. For example, in the substrate support 400, the radially inner portion of the first extraction channel 480 is located below the radially outer portion of the second extraction channel 481. Similarly, the radially inner portion of the peripheral channel 482 may be located below the radially outer portion of the multifunctional channel 483, although this is not shown in Figure 10. As a result, channels 480, 481, 482, and 483 can each be positioned in the radially outer region of the substrate support 400. The openings 460, 461, 462, and 463 must be positioned near this region to provide the necessary functions. Thus, the horizontal portions of the passages 470, 471, 472, and 473 can be shortened to avoid undesirably large flow resistance.

[0125]

[0123] Figure 11 shows another substrate support 500 according to the present invention. Similar to the substrate support 400, in the substrate support 500, channels 480, 481, 482, and 483 are arranged in a stacked configuration. Specifically, the first extraction channel 580 and the multifunction channel 583 are located at the interface between the lower component 510 and the core component 511, and the second extraction channel 581 and the periphery channel 582 are located at the interface between the core component 511 and the upper component 512. The first adjustment channel 591 is located radially inward of the first extraction channel 580 and the second extraction channel 581, and radially outward of the periphery channel 582 and the multifunction channel 583. As already described in this disclosure, positioning the first adjustment channel 591 in close proximity to the first extraction channel 580 and the second extraction channel 581 means that the thermal load in the first extraction channel 580 and the second extraction channel 582 can be effectively reduced.

[0126]

[0124] Generally, the concept of "stacked channels" means that the positions of various channels can be compressed radially. That is, all of channels 580, 581, 582, and 583 can be placed within a smaller area. This means that each of channels 580, 581, 582, and 583 can be placed closer to the radial edge of the substrate support 500. As mentioned above, this is beneficial because the openings 560, 561, 562, and 563 must be placed near the edge in order to provide their functions. By providing channels 580, 581, 582, and 583 closer to the openings 560, 561, 562, and 563 in the radial direction, the length of the horizontal portion of the passages 571, 572, and 573 can be shortened.

[0127]

[0125] Generally, the presence of two bonding layers means that channels 280, 281, 282, 283 and adjustment channels 291, 292, 293 can be formed at one of the interfaces (e.g., the interface between the lower component 210 and the core component 211), and that the horizontal portions of passages 270, 271, 272, 273 can be formed at the other interface (e.g., the interface between the core component 211 and the upper component 212). Thus, the locations of openings 260, 261, 262, 263 are not coupled to (i.e., independent of) the locations of channels 280, 281, 282, 283. Additionally or alternatively, the presence of two bonding layers means that channels 280, 281, 282, 283 can be "stacked" with each other, reducing the size of the area of ​​components 210, 211, 212 required to accommodate them. The increased design flexibility provided by offering two bonding layers means that the substrate support 200 can be configured to effectively provide the functions of the additional openings 262, 263, and to exhibit good thermal performance.

[0128]

[0126] The exemplary substrate supports 200, 400, and 500 described above all include three components and two bonding layers. However, the present invention is not limited to this configuration. Generally, increasing the number of components to be bonded increases the degree of design freedom. This is because features such as channels (e.g., channels 280, 281, 282, 283, and adjustment channels 291, 292, 293) and passages (e.g., passages 271, 272, 273) can be placed at multiple locations within the thickness (i.e., the dimension in the vertical z direction).

[0129]

[0127] However, it must be recognized that increasing the number of components 210, 211, and 212 within the substrate support 200 can contribute to an increase in the complexity of the required manufacturing process. Forming the substrate support 200 with three components 210, 211, and 212 and two bonding layers provides a good balance between offering design freedom for positioning features within the substrate support 200 and avoiding an unnecessary increase in the complexity of the manufacturing process.

[0130]

[0128] As described above, a thermal load (i.e., a cooling load) is applied to the surfaces of various channels 280, 281, 282, and 283 as a result of the evaporation of the immersion fluid on the surface. The thermal load may depend on the presence or absence of immersion fluid in channels 280, 281, 282, and 283. If fluid is present on the surfaces of channels 280, 281, 282, and 283, evaporation occurs, and a cooling load is applied to the surfaces of channels 280, 281, 282, and 283. If fluid is not present in channels 280, 281, 282, and 283, evaporation does not occur, and therefore, no cooling load may be applied to the surfaces of channels 280, 281, 282, and 283. If fluid is present in channels 280, 281, 282, and 283, the magnitude of the cooling load may depend on the evaporation rate of the fluid from the surfaces of channels 280, 281, 282, and 283. The evaporation rate may depend on the relative humidity (RH) of the gas (e.g., air) flowing through channels 280, 281, 282, and 283. If the relative humidity is 100%, no evaporation occurs.

[0131]

[0129] To ensure that the temperature of the substrate support 200 is kept substantially uniform and within acceptable limits, the substrate support 200 may include a thermal control system. The thermal control system may include control channels 291, 292, and 293. The thermal control system may further include a plurality of heaters (not shown) distributed across the entire surface of the substrate support 200. For example, there may be six or more heaters distributed across the entire surface of the substrate support 200. These heaters may be actively controlled. That is, the thermal control system may include one or more temperature sensors (not shown), and a control system (not shown) may control the operation of the thermal control system (e.g., heaters) based on data recorded by these temperature sensors.

[0132]

[0130] During operation, the first extraction channel 280 may contain immersion fluid for most of the time the substrate support 200 is operating. This is because the first extraction channel 280 is primarily responsible for extracting immersion fluid from the area between the substrate W and the substrate support 200. In other words, the first extraction channel 280 can extract most of the immersion fluid. The second extraction channel 281 may extract less immersion fluid than the first extraction channel 280. For this reason, the second extraction channel 281 may not contain immersion fluid for most of the time the substrate support 200 is operating. This means that the second extraction channel 281 may become "completely dry" during the operation of the substrate support 200. In other words, during the operation of the substrate support 200, all of the immersion fluid in the second extraction channel 281 may be extracted and / or evaporated, leaving the second extraction channel 281 dry. As a result, the cooling load applied to the surface of the second extraction channel 281 may vary as a function of time.

[0133]

[0131] If the cooling load applied to the surfaces of channels 280, 281, 282, and 283 fluctuates over time, it may be difficult for the thermal control system to effectively regulate the temperature of the substrate support 200. For example, if the cooling load on the surfaces of channels 280, 281, 282, and 283 changes (e.g., increases), it is necessary to change the operation of the heaters near channels 280, 281, 282, and 283 (i.e., heat them) to keep the overall temperature of the substrate support 200 near channels 280, 281, 282, and 283 substantially constant. However, it may take some time to detect changes in the cooling load and change the operation of the heaters. Therefore, the temperature of the substrate support 200 may fluctuate (i.e., not be constant) for a while. As described above, if the temperature of the entire or a part of the substrate support 200 fluctuates over time, the substrate support 200 may undergo temporary structural deformation, which may result in increased overlay errors. Furthermore, if the thermal control system needs to regulate the temperature of the substrate support 200 while fluctuating cooling loads are applied to channels 280, 281, 282, and 283, a complex control system may be required.

[0134]

[0132] In some embodiments, the substrate support 200 may include additional features that improve the temporal uniformity of the cooling load applied to the surface of the second extraction channel 281. These additional features can be achieved by one or more of the following: (i) ensuring that the immersion fluid is present on the surface of the second extraction channel 281 for substantially the entire duration that the substrate support 200 is operating; and (ii) ensuring that the air flowing into the second extraction channel 281 is substantially saturated (i.e., the relative humidity of the air flowing into the second extraction channel 281 is 100% or close to 100%). In the embodiments described below, this is achieved by fluidizing the second extraction channel 281 and / or the second fluid extraction recess 251 with a reliable (i.e., substantially constant) immersion fluid source.

[0135]

[0133] Figure 12 shows a cross-sectional view of a substrate support 200 according to the present invention. This cross-sectional view extends into the vertical plane (i.e., the x / z plane). The substrate support 200 may be the same as the substrate support 200 shown in Figure 7, except as described below. In the diagram of the substrate support 200 shown in Figure 12, the radially outward direction is to the right. Only the radially outward portion of the substrate support 200 is shown. That is, the substrate support 200 may continue to the left of the portion shown in Figure 12. The cross-sectional view of the substrate support 200 shown in Figure 12 is a different cross-sectional view from the substrate support 200 shown in Figure 7. Each of the cross-sectional views shown in Figure 7 and Figure 12 passes through the diameter of the substrate support 200, but the plane shown in the cross-section can be rotated and shifted by, for example, an angle of 15 degrees. Therefore, some of the features of the substrate support 200 that are visible in Figure 7 (e.g., passages 271, 272, 273) may not be visible. The recesses 250, 251, 252, and 253, which are roughly shown, are also visible in Figure 12. This is because the recesses 250, 251, 252, and 253 extend in the circumferential direction of the substrate support 200, and are therefore visible regardless of their angular position in the vertical cross-sectional view.

[0136]

[0134] In the substrate support 200 shown in Figure 12, the second extraction channel 281 is in fluid communication with the first adjustment channel 291. The first adjustment channel 291 may contain adjustment fluid throughout the operation of the substrate support 200. By fluid communication between the second extraction channel 281 and the first adjustment channel 291, the adjustment fluid can flow from the first adjustment channel 291 to the second extraction channel 281. Therefore, even if the immersion fluid in the second extraction channel 281 evaporates, a stable supply of adjustment fluid can be supplied to the second extraction channel 281, so the second extraction channel 281 does not dry out.

[0137]

[0135] The second extraction channel 281 can be fluidly connected to the first adjustment channel 291 via the first connection passage 275. The configuration of the first connection passage 275 is not particularly limited as long as it fluidly connects the second extraction channel 281 and the first adjustment channel 291. In the substrate support 200 shown in Figure 12, the first connection passage 275 includes a horizontal section at the interface between the upper component 212 and the core component 211. The first connection passage 275 further includes two vertical sections. One of the vertical sections connects the horizontal section to the first adjustment channel 291, and the other of the vertical section connects the horizontal section to the second extraction channel 281.

[0138]

[0136] Figure 13 shows a cross-sectional view of a substrate support 200 according to the present invention. The diagram shown in Figure 13 may be substantially identical to the diagram shown in Figure 12. The substrate support 200 shown in Figure 13 may be substantially identical to the substrate support 200 shown in Figure 7, except for the points described below.

[0139]

[0137] In the substrate support 200 shown in Figure 13, the second extraction channel 281 is in fluid communication with the first extraction channel 280. As described above, the first extraction channel 280 may contain immersion fluid for most of the time the substrate support 200 is operating. By fluidizing the second extraction channel 281 with the first extraction channel 280, the immersion fluid can flow from the first extraction channel 280 to the second extraction channel 281. As a result, it is possible to prevent the second extraction channel 281 from drying out completely.

[0140]

[0138] The first extraction channel 280 can be fluidly connected to the second extraction channel 281 via the second connecting passage 276. The second connecting passage 276 can be the same as the first connecting passage 275, but it differs in that it fluidly connects the first extraction channel 280 and the second extraction channel 281, rather than the second extraction channel 281 and the first adjustment channel 291.

[0141]

[0139] In the embodiments shown in Figures 12 and 13, the ability to supply fluid to the second extraction channel 281 prevents the second extraction channel 281 from drying out completely. That is, fluid may be present on the surface of the extraction channel 281 for most of the time the substrate support 200 is operating. This allows for a more uniform cooling load over time on the surface of the second extraction channel 281. In some embodiments, the fluid supplied to the second extraction channel 281 may be sufficient to keep the entire surface of the second extraction channel 281 wet. In this case, the relative humidity inside the second extraction channel 281 may be 100% (or close to 100%). In this case, no evaporation occurs (or only a very small amount of evaporation occurs). Therefore, no thermal load is applied to the surface of the second extraction channel 281 (or only a very small thermal load). This means that the thermal control system does not need to provide significant compensation for the cooling load applied to the second extraction channel 281, and the temperature of the substrate support 200 can be made more uniform over time.

[0142]

[0140] When the first adjustment channel 291 is in fluid communication with the second extraction channel 281 (Figure 12), the pressure in the second extraction channel 281 is lower than the pressure in the first adjustment channel 291, allowing the adjustment fluid in the first adjustment channel 291 to be drawn into the second extraction channel 281. If this is not the case, the fluid can be drawn from the first adjustment channel 291 into the second extraction channel 281 by the capillary force in the first connecting passage 275. Similarly, when the first extraction channel 280 is in fluid communication with the second extraction channel 281 (Figure 13), the pressure in the second extraction channel 281 is lower than the pressure in the first extraction channel 280, allowing the immersion fluid to be drawn from the first extraction channel 280 into the second extraction channel 281. If this is not the case, fluid can be drawn from the first extraction channel 280 into the second extraction channel 281 by capillary force in the second connecting passage 276.

[0143]

[0141] In some cases, the transfer of fluid to the second extraction channel 281 may be actively controlled. For example, an active controller (not shown) may include a valve and / or pressure gradient generating means. The active controller may be configured to facilitate the fluid flow (from the first extraction channel 280 or the first regulating channel 291) to the second extraction channel 281. Alternatively, the active controller may be configured to block the fluid flow to the second extraction channel 281.

[0144]

[0142] Figure 14 shows a cross-sectional view of a substrate support 200 according to the present invention. Figure 14 is the same cross-sectional view as the cross-sectional views of Figures 12 and 13. The substrate support 200 shown in Figure 14 may be substantially identical to the substrate support 200 shown in Figure 7, except for the points described below. In the substrate support 200 shown in Figure 14, the first adjustment channel 291 is in fluid communication with the second fluid extraction recess 251. The second fluid extraction recess 251 may simply be called the fluid extraction recess. By fluidizing the first adjustment channel 291 with the second fluid extraction recess 251, the adjustment fluid flows from the first adjustment channel 291 to the second fluid extraction recess 251, thereby ensuring that the second fluid extraction recess 251 remains wet (i.e., has fluid on its surface) for most of the time the substrate support 200 is operating.

[0145]

[0143] The first adjustment channel 291 can be fluidly connected to the second fluid extraction recess 251 by a third connecting passage 277. The third connecting passage 277 may include a first portion 277a in the core component 211 and a second portion 277b in another component such as the upper component 212.

[0146]

[0144] The second extraction channel 281 is configured to extract the immersion fluid from the second fluid extraction recess 251 (through the second extraction opening 261 and the second passage 271). If the surface of the second fluid extraction recess 251 is consistently wet, the air drawn in through the second extraction opening 261 may be substantially saturated. That is, the fluid (e.g., air) entering the second extraction channel 281 may have a high relative humidity (e.g., above 90%, preferably above 95%, preferably above 98%). This may mean that the evaporation rate in the second extraction channel 281 is low. As a result, the cooling load on the surface of the second extraction channel 281 may be very low, regardless of whether fluid is present on the surface of the second extraction channel 281. If the air is substantially saturated, the evaporation rate may be close to zero, regardless of whether fluid is present on the surface of the second extraction channel 281. Therefore, by fluidly communicating the first adjustment channel 291 with the second fluid extraction recess 251, the cooling load applied to the surface of the second extraction channel 281 can be made substantially constant over time.

[0147]

[0145] Figure 15 shows a partial cross-sectional view of the substrate support 200. The substrate support 200 may be substantially identical to the substrate support 200 shown in Figure 7. Furthermore, the cross-sectional view shown in Figure 15 may be identical or substantially identical to the cross-sectional view shown in Figure 7, except for the points described below. Since the cross-sectional view shown in Figure 15 is substantially identical to the cross-sectional view shown in Figure 7, the second passage 271 (i.e., the passage connecting the second extraction channel 261 and the second extraction channel 281) can be seen. Several features, such as the first, third, and fourth passages 270, 272, 273, etc., have been removed from the figure to improve the clarity of the features described.

[0148]

[0146] The substrate support 200 shown in Figure 15 is a variation of the substrate support 200 shown in Figure 12, in that the first adjustment channel 291 and the second extraction channel 281 are in fluid communication, similar to the substrate support 200 shown in Figure 12. This fluid communication is provided by a fourth connecting passage 278 that connects the first adjustment channel 291 to the second passage 271. Thus, fluid communication between the first adjustment channel 291 and the second extraction channel 281 is made possible via the fourth connecting passage 278 and the second passage 271. It will be understood that the same can be done to fluidize the first extraction channel 280 to the second extraction channel 281, although this is not shown. That is, the first extraction channel 280 can be fluidized to the second extraction channel 281 by connecting the first extraction channel 280 to the first passage 271.

[0149]

[0147] The structure of the connecting passages 275, 276, 277, and 278 is not particularly limited. The first connecting passage 275 and the second connecting passage 276 are shown to include a horizontal section with a small vertical section connecting this horizontal section to various channels, but this is not always the case. For example, the first and second connecting passages 275 and 276 may be substantially vertical. This may be the case with the "stacked channel" structure described above.

[0150]

[0148] Multiple connection passages can be provided. For example, if the first adjustment channel 291 is in fluid communication with the second extraction channel 281, multiple first connection passages 275 can be provided. Multiple connection passages can be distributed in the circumferential direction of the substrate support 200. The number of connection passages (for example, the number of first connection passages 275 when the first adjustment channel 291 is in fluid communication with the second extraction channel 281) can be greater than 10 and less than 100. Increasing the number of connection passages can improve the uniformity of fluid transfer to the second extraction channel 281.

[0151]

[0149] The diameters of the first, second, third, and fourth connecting passages 275, 276, 277, and 278 (especially the first, third, and fourth connecting passages 275, 277, and 278) can be made small. Specifically, the diameters of the first and third connecting passages 275 and 277 can be made small enough to provide flow resistance. Flow resistance can ensure that the volume of fluid flowing into the second extraction channel 281 or the second fluid extraction recess 251 is not excessive. This may be particularly important in the embodiment shown in Figure 14. If an excessive amount of fluid flows from the first regulating channel 291 into the second fluid extraction recess 251, the second fluid extraction recess 251 may overflow. The diameters of the first, second, third, and fourth connecting passages 275, 276, 277, and 278 can be made small enough so that the flow resistance in the connecting passages 275, 276, 277, and 278 is caused by capillary forces. The flow resistance in the first, second, third, and fourth connecting passages 275, 276, 277, and 278 may be increased by providing them with additional components. Additional components may include a porous medium or microsieves (not shown). Additionally or alternatively, additional components may include a permeable membrane (not shown). The permeable membrane allows water vapor to pass through the connecting passages while keeping the majority of the fluid in the different channels separate.

[0152]

[0150] A substrate support 200 in which the extraction channel and / or extraction recess is in fluid communication with a fluid source within the substrate support (e.g., another extraction channel or regulating channel) can be implemented with a substrate support 200 having different features from the substrate support 200 described above, as shown in Figure 7.

[0153]

[0151] In some embodiments, the first fluid extraction opening 260, the first passage 270, and the first extraction channel 280 (collectively referred to as the first drain system) may be configured as described below with respect to Figures 16 to 19. For example, the first drain system in the embodiments shown in Figures 7 to 15 may be configured as described below with respect to Figures 16 to 19. The configuration of the first drain system described below and shown in Figures 16 to 19 may also be implemented in substrate supports other than those shown in Figures 7 to 15, for example, in the substrate support 20 shown in Figure 2 (in this case, the first drain is equivalent to the first drain 10 of the substrate support 20 shown in Figure 2).

[0154]

[0152] As described above, in some embodiments, the first fluid extraction opening 260 is located radially outward of the outer seal 231 (i.e., within the first fluid extraction recess 250) and radially outward of the edge of the substrate W. The first fluid extraction opening 260 is in fluid communication with the first extraction channel 280, allowing fluid (i.e., immersion liquid and gas) to be extracted from the first fluid extraction recess 250 through the first fluid extraction opening 260 and the first extraction channel 280. The first fluid extraction opening 260 may be in fluid communication with the first extraction channel 280 via the first passage 270.

[0155]

[0153] Furthermore, as described above, the fluid handling structure IH located between the projection system PS and the substrate support WT is used to confine the immersion fluid in the immersion space between the final element of the projection system PS and the substrate W. When the lithography apparatus is in use, the substrate support WT moves relative to the fluid handling structure IH. During this relative movement, the fluid handling structure IH moves across the gap 5 between the coverings 101, 201 and the substrate W.

[0156]

[0154] The primary function of the first drain system is to help prevent gas bubbles from entering the immersion space where the fluid of the fluid handling structure IH is present. Such bubbles can adversely affect imaging of the substrate W. The first drain system is present to help prevent gas in the gap 5 from escaping into the immersion space between the projection system PS and the substrate support WT, 200. If gas were to escape into the immersion space, this could result in bubbles floating in the immersion space. Such bubbles, if present in the path of the radiation beam B, could lead to imaging errors. The first drain system is configured to extract gas from the gap 5 between the edge of the substrate W and the surface of the substrate support WT, 200, for example, the upper surface edge of the coverings 101, 201. Another function of the first drain system is to extract the immersion fluid from between the substrate W and the substrate supports 200, 300, 400, 500 (i.e., from the first fluid extraction recess 250).

[0157]

[0155] After the fluid handling structure IH moves relative to the substrate W across the gap 5 between the coverings 101, 201 and the substrate W, a small amount of immersion fluid may remain on the surface of the substrate W in the area over which the fluid handling structure IH has moved. This may cause bubbles and water marks on the surface of the substrate W, which could lead to defects (i.e., errors in the pattern applied to the surface of the substrate W). To minimize the amount of liquid remaining in this area of ​​the substrate W surface after the fluid handling structure IH has passed over that area of ​​the substrate W surface, the first drain system must efficiently and uniformly (spatially and temporally) extract the liquid from the first fluid extraction recess 250.

[0158]

[0156] Figure 16 is a cross-sectional view of the radially outer portion of the substrate support 200, showing the first drain system (including the first fluid extraction opening 260, the first passage 270, and the first fluid extraction channel 280, which have already been described).

[0159]

[0157] In the embodiment shown in Figure 16, the first fluid extraction opening 260 extends circumferentially from the substrate support 200. The first fluid extraction opening 260 is formed on the upper surface of the substrate support 200. The first fluid extraction opening 260 may be defined by the upper part of the first fluid extraction groove 220. The first fluid extraction groove 220 is provided as a recess in the upper surface of the substrate support 200. The upper part of the fluid extraction groove 220 is the portion of the first fluid extraction groove 220 that is at the same level as the upper surface of the substrate support 200.

[0160]

[0158] The first fluid extraction groove 220 may extend circumferentially from the substrate support 200. The cross-sectional shape of the first fluid extraction groove 220 is not particularly limited. As shown in Figure 16, the cross-sectional shape of the first fluid extraction groove 220 is substantially rectangular. Alternatively, the cross-sectional shape of the first fluid extraction groove 220 may be circular (i.e., round), V-shaped, or L-shaped. In some embodiments, the edge between the first fluid extraction groove 220 and the upper surface of the substrate support 200 is chamfered.

[0161]

[0159] The first fluid extraction channel 280 is in fluid communication with the first fluid extraction opening 260 via the first passage 270 and the first fluid extraction groove 220. The immersion fluid flows through the slit 202 to flow from the first fluid extraction recess 250 to the first fluid extraction groove 220. The slit 202 is defined by the upper surface of the substrate support 200 and the lower surface of the covering 201. Specifically, the slit 202 is the gap between the upper surface of the substrate support 200 and the lower surface of the covering 201. The height of the slit 202 is indicated by dimension d2. The slit 202 extends from the radially inner end 202a (which may be defined by the edge of the covering 201) to the radially outer end 202b (which may be defined by the edge of the first fluid extraction opening 260). The immersion fluid flows from the first fluid extraction recess 250 through the slit 202 (from the radially inner end 202a to the radially outer end 202b), through the first fluid extraction opening 260 into the first fluid extraction groove 220, and further through the first passage 270 and the first fluid extraction channel 280 in order to be extracted from the first fluid extraction recess 250.

[0162]

[0160] When the immersion fluid enters the first fluid extraction recess 250, the extraction pressure in the first fluid extraction recess 250 (a pressure lower than the pressure around the substrate W) draws the immersion fluid into the slit 202. This can cause the slit 202 to become blocked by the immersion fluid. For a certain period of time after the immersion fluid first enters the first fluid extraction recess 250, the first passage 270 and the first fluid extraction groove 220 are substantially empty. When the slit 202 is blocked by the immersion fluid and the first passage 270 and the first fluid extraction groove 220 are substantially empty, the pressure at the radially outer end 202b of the slit 202 is substantially the same as the extraction pressure in the first extraction channel 280. Therefore, the pressure difference on the slit 202 (i.e., between the radially inner end 202a and the radially outer end 202b of the slit 202) is relatively large. As a result, the flow rate through the slit 202 is relatively large. As a result, the immersion fluid is extracted relatively quickly from the first fluid extraction recess 250.

[0163]

[0161] As the first drain system continues to extract immersion fluid from the first fluid extraction recess 250, the first passage 270 and / or the first fluid extraction groove 220 may become filled with immersion fluid. This may cause the first passage 270 and / or the first fluid extraction groove 220 to become blocked with immersion fluid. This means that the pressure at the radially outer end 202b of the slit 202 may be greater than the extraction pressure in the first extraction channel 280. As a result, the pressure difference over the slit 220 may be relatively small (i.e., smaller than when the first passage 270 and the first fluid extraction groove 220 are not blocked with immersion fluid). Therefore, the immersion fluid may be extracted from the first fluid extraction recess 250 at a slower rate. This means that after the fluid handling structure IH has passed through the gap 5, some of the immersion fluid may remain on the surface of the substrate W adjacent to the gap 5. This may lead to defects as described above.

[0164]

[0162] In order to ensure that the immersion fluid is efficiently and uniformly extracted from the first fluid extraction recess 250, the first fluid extraction groove 220 may be configured to delay the time when the first passage 270 is filled with the immersion fluid. Preferably, the first fluid extraction groove 220 is configured such that the time when the first passage 270 is filled with the immersion fluid is later than the time when substantially all of the immersion fluid has been extracted from the first fluid extraction recess 250.

[0165]

[0163] In order to delay the time when the first passage 270 is filled with immersion fluid, the volume of the first fluid extraction groove 220 can be made relatively large. Therefore, more immersion fluid must accumulate in the first fluid extraction groove 220 before the immersion fluid fills the first passage 270. In order to achieve a relatively large volume of the first fluid extraction groove 220, the cross-sectional area of ​​the first fluid extraction groove 220 is 1 mm 2 Very, preferably 3mm 2 More preferably 5mm 2 It should be "extraordinary". The cross-sectional area of ​​the first fluid extraction groove 220 is 10 mm². 2It is sufficient to set it to less than 0.5 mm, preferably more than 1 mm, and even more preferably more than 1.5 mm. The depth (d3) of the first fluid extraction groove 220 must be less than about 5 mm, preferably less than about 2 mm. When the depth of the first fluid extraction recess 220 is less than 5 mm (preferably less than 2 mm), the flow in the first fluid extraction recess 220 is promoted by capillary force, and the effect of gravity on the flow is not dominant (e.g., slight). This means that dripping of the immersion fluid in the first fluid extraction groove 220 is prevented. If dripping occurs in the first fluid extraction groove 220, the lower part of the first fluid extraction groove 220 will be filled before the rest of the first fluid extraction groove 220, and therefore the first passage 270 will be blocked with the immersion fluid after a shorter time. The depth (d3) of the first fluid extraction groove 220 is the dimension perpendicular to the upper surface of the substrate support 200. The maximum width (d4) of the first fluid extraction groove 220 may be greater than 0.5 mm, preferably greater than 1.5 mm, and more preferably greater than 3 mm. The width (d4) of the first fluid extraction groove 220 may be less than 5 mm. The width (d4) of the first fluid extraction groove 220 is the dimension parallel to the upper surface of the substrate support 200. The width (d4) of the first fluid extraction groove 220 is the dimension between the radially inner wall of the first fluid extraction groove 220 and the radially outer wall of the first fluid extraction groove 220.

[0166]

[0164] In order to ensure that the structural integrity of the substrate support 200 is not impaired by the presence of the first fluid extraction groove 220, the first fluid extraction groove 220 can be isolated from other passages and channels within the substrate support 200, and also isolated from the edges of the substrate support 200. For example, the distance between the first fluid extraction groove 220 and the edge of the substrate support (specifically, the distance between the radially outer wall of the first fluid extraction groove 220 and the radially outer wall of the substrate support 200) may be greater than 0.1 mm, preferably greater than 0.3 mm, and more preferably greater than 0.5 mm. The distance between the lower wall of the first fluid extraction groove 220 and the upper wall of the first fluid extraction channel 280 may be greater than 0.1 mm, preferably greater than 0.3 mm, and more preferably greater than 0.5 mm. If the first fluid extraction groove 220 is formed in the upper component (e.g., upper component 212), the distance between the lower wall of the first fluid extraction groove 220 and the interface between the upper component 212 and the core component 211 should be greater than 0.1 mm, preferably greater than 0.3 mm, and more preferably greater than 0.5 mm.

[0167]

[0165] The length of the slit 202 (i.e., the distance between the radially inner end 202a and the radially outer end 202b of the slit 202) may be greater than 0.3 mm, preferably greater than 0.5 mm. The length of the slit 202 may be greater than 5 times the height of the slit 202, preferably greater than 15 times the height of the slit, and even more preferably greater than 20 times the height of the slit. Increasing the length of the slit 202 may increase the magnitude of the negative pressure in the first fluid extraction groove 220, the first passage 270, and the first fluid extraction channel 280. It may be preferable to make the length of the slit 202 sufficiently short so that the negative pressure in the first fluid extraction groove 220, the first passage 270, and the first fluid extraction channel 280 does not become undesirably large.

[0168]

[0166] The first passage 270 may be connected to the first fluid extraction groove 220 at its most downstream point within the first fluid extraction groove 220 (i.e., to maximize the length of the flow path between the entrance of the first passage 270 and the radially outer end 202b of the slit 202). This may be to further delay filling the first passage 270 with immersion fluid after the first drain system has begun to extract immersion fluid from the first extraction recess 250. In the substrate support 200 shown in Figure 16, the most downstream point is at the radially outer edge of the first fluid extraction groove 220.

[0169]

[0167] The first passage 270 can be angled (i.e., not perpendicular to the top surface of the substrate support 200). For example, the inlet of the first passage 270 (i.e., where the first passage 270 merges with the first fluid extraction groove 220) can be radially outward of the outlet of the first passage 270 (i.e., where the first passage 270 merges with the first extraction channel 280). This makes it possible to make the position of the inlet of the first passage 270 independent of the position of the first extraction channel 280.

[0170]

[0168] It is preferable that the flow resistance in the first fluid extraction groove 220 is relatively large in the circumferential (i.e., azimuth) direction. When the fluid handling structure IH passes over the gap 5, the immersion fluid can flow into the circumferential portion of the first fluid extraction recess 250 (for example, the immersion fluid may be present in a 30-degree angular range of the fluid extraction recess 250). If the immersion fluid is being extracted by the first drain system, it flows into the corresponding circumferential portion of the slit 202. As described above, if this circumferential portion of the slit 202 is blocked, a relatively large pressure difference is created on the slit 202, and therefore a relatively high immersion fluid extraction velocity is produced from the first fluid extraction recess 250. However, the portion of the slit 202 other than the circumferential portion containing the immersion fluid (for example, the remaining 330 degrees) is not blocked. Therefore, if the circumferential flow resistance in the first fluid extraction groove 220 is small, the pressure at the radially outer end 202b of the slit 202 in the circumferential portion corresponding to the location of the immersion fluid in the fluid extraction recess 250 may be greater than the extraction pressure in the first fluid extraction channel 280. In other words, the small flow resistance in the first fluid extraction groove 220 may reduce the pressure difference on the slit 202. Therefore, the extraction rate of the immersion fluid from the first fluid extraction recess 250 may be reduced. This is particularly noticeable when the cross-sectional area of ​​the first fluid extraction groove 220 is large. In the above explanation, the examples of 30 degrees and 330 degrees are used merely to aid the explanation.

[0171]

[0169] Taking the above into consideration, a plurality of flow limiting members can be provided in the first fluid extraction groove 220. The plurality of flow limiting members can be dispersed in the circumferential direction of the first fluid extraction groove 220. The plurality of flow limiting members can be configured to increase the flow resistance in the circumferential direction within the first fluid extraction groove 220.

[0172]

[0170] Figures 17A and 17B show cross-sectional views of the radially outer portion of the substrate support 200 in which flow restricting members 225 and 226 are located within the first fluid extraction groove 220. Figure 18 shows a schematic plan view of the first fluid extraction groove 220. As shown in Figure 18, the substrate support 200 may include a plurality of first passages 270 distributed circumferentially along the first fluid extraction groove 220. The flow restricting members 225 and 226 may be positioned between adjacent first passages 270. The flow restricting members 225 and 226 may define individual circumferential portions of the first fluid extraction groove 220. Each first passage 270 may be located within its own individual circumferential portion.

[0173]

[0171] The flow limiting members 225 and 226 can completely isolate the individual circumferential portions of the first fluid extraction groove 220 from each other. Complete isolation of the individual circumferential portions ensures that the pressure difference on the slit 202 is not reduced by the circumferential portion of the slit 202 that is not filled with immersion fluid.

[0174]

[0172] The individual circumferential portions may be partially isolated from each other by flow limiting members 225, 226 (i.e., fluid can flow between the individual circumferential portions, but this flow is restricted compared to the flow within each individual circumferential portion). By partially isolating (but not completely) the individual circumferential portions of the first fluid extraction groove 220, even if the first passage 270 corresponding to one individual circumferential portion of the first fluid extraction groove 220 is blocked, the immersion fluid in that individual circumferential portion can be extracted from there. This is because the immersion fluid in an individual circumferential portion can flow to an adjacent individual circumferential portion and then be extracted from there. Thus, by partially isolating (but not completely) the individual circumferential portions of the first fluid extraction groove 220, the robustness of the first drain system can be improved.

[0175]

[0173] In the embodiments shown in Figures 17A and 17B, the flow limiting members 225 and 226 are vertical walls. The vertical walls may be called partitions. The partitions may extend over a portion of the cross-sectional area of ​​the first fluid extraction groove 220. In some embodiments, the partitions extend over a large portion of the cross-sectional area of ​​the first fluid extraction groove 220 (e.g., more than 50%, preferably more than 80%, and even more preferably more than 90%). Such partitions may reduce flow resistance in the first fluid extraction groove 220 in the circumferential direction. In some embodiments, the partitions may extend over the entire cross-sectional area of ​​the first fluid extraction groove 220 to prevent flow in the first fluid extraction groove 220 in the circumferential direction.

[0176]

[0174] In the embodiment shown in Figure 17A, the flow limiting member 225 is connected to the lower surface of the covering 201. That is, the flow limiting member 225 extends downward from the lower surface of the covering 201 into the first fluid extraction groove 220.

[0177]

[0175] Additionally or alternatively, the flow limiting member 226 may be connected to the first fluid extraction groove 220. For example, in the embodiment shown in Figure 17B, the flow limiting member 226 is connected to the lower surface of the first fluid extraction groove 220. That is, the flow limiting member 226 extends from the lower surface of the first fluid extraction groove 220.

[0178]

[0176] The flow limiting members 225 and 226 may be formed integrally with the main body of the substrate support 200. Alternatively, the flow limiting members 225 and 226 may be insertion parts configured to be attached to the main body of the substrate support 200.

[0179]

[0177] The flow restricting members 225 and 226 can be impermeable (i.e., fluid cannot pass through them). Alternatively, the flow restricting members 225 and 226 can be permeable. For example, the flow restricting members 225 and 226 can be porous or contain small holes.

[0180]

[0178] Figure 19 shows a cross-sectional view of the radially outer portion of the substrate support 200 showing the first drain system. The substrate support 200 shown in Figure 19 includes an upper layer 212, a core layer 211, and a lower layer 210, as described above.

[0181]

[0179] In the substrate support 200 shown in Figure 19, the first fluid extraction groove 220 has a more complex cross-sectional shape than that of the substrate support 200 shown in Figure 16. This shape will be explained in more detail below.

[0182]

[0180] The cross-sectional shape of the first fluid extraction groove 220 can vary as a function of the height within the substrate support 200. For example, the first fluid extraction groove 220 may have a first width on the upper surface and a second width below the upper surface. The first width can be smaller than the second width. This makes it possible to increase the volume of the first fluid extraction groove 220 without reducing the length of the slit 202.

[0183]

[0181] The cross-sectional shape of the first fluid extraction groove 220 is formed by three simple shapes, namely a first shape 220a, a second shape 220b, and a third shape 220c. The first, second, and third shapes 220a, 220b, and 220c may be rectangular. The first shape 220a and the second shape 220b may be defined within the upper layer 212. The third shape 220c may be defined within the core layer 211.

[0184]

[0182] The first shape 220a may be radially outward of the second shape 220b. The first shape 220a may extend from the upper surface of the upper component 212 to the interface between the upper component 212 and the core component 211. The second shape 220b may extend upward from the interface between the core component 211 and the upper component 212, but may not extend to the upper surface of the upper component 212. The third shape 220c may extend downward from the interface between the upper layer 212 and the core layer 211.

[0185]

[0183] By configuring the cross-sectional shape of the first fluid extraction groove 220 with a plurality of simple shapes, it is possible to maximize the volume of the first fluid extraction groove 220 while maintaining the necessary separation from, for example, the circumferential edge of the substrate support 200 and other channels and passages within the substrate support 200.

[0186]

[0184] The material of the substrate support 200 is not particularly limited and may be any suitable material known in the art. Preferably, the substrate support 200 may be made of silicon-wet silicon carbide (SiSiC). Alternatively, the substrate support may be formed of ZeroDua® (aluminosilicate glass ceramic, cordierite, silicon carbide (SiC), or diamond SiSiC).

[0187]

[0185] Next, a manufacturing process that may be used to manufacture the substrate support 200 will be described. First, the lower component 210 and the core component 211 are prepared. For example, recesses for internal channels such as channels 280, 281, 282, 283 and adjustment channels 291, 292, 293 (or adjustment spiral 290) can be formed. This can be achieved using standard manufacturing techniques such as CNC machining.

[0188]

[0186] Next, the lower component 210 can be joined to the core component 211. The joining process may include penetration bonding or diffusion bonding.

[0189]

[0187] Diffusion bonding is based on the principle of solid diffusion, in which two components are bonded together when they are held together under sufficient pressure and temperature, by the movement of atoms from one component to the other and vice versa. To bond two components such as a lower component 210 and a core component 211, if the two components are made of SiSiC, a pressure of about 2000 kN and a temperature of about 1350 °C may be required. Generally, the required temperature may be close to but lower than the melting temperature of silicon. To assist the diffusion bonding process, a coating layer may be applied to the surfaces to be bonded. For example, a coating may be applied to the underside of the core component 211 before bonding the lower component 210 and the core component 211. The coating may be applied by physical vapor deposition (PVD). The coating may contain at least one of titanium, silicon, and aluminum. The composition of the coating should contain trace amounts or more of titanium, silicon, and aluminum. For example, the coating may be substantially made of at least one of titanium, silicon, and aluminum. In other words, the coating can essentially consist of at least one of titanium, silicon, and aluminum. Preferably, the coating may contain titanium. The titanium coating may be about 500 nm thick. An antioxidant protective layer can be provided to the titanium coating. The antioxidant layer may contain silicon. The antioxidant layer may be about 10 nm thick.

[0190]

[0188] After the first joining step, vertical holes such as the second passage 271, the third passage 273, and the second vertical portion of the fourth passage 271 can be formed in the core component 211. These vertical portions can be formed by electrical discharge machining (EDM).

[0191]

[0189] Next, the upper component 212 can be prepared. For example, the horizontal sections of channels 271, 272, and 273 can be formed using an advanced structuring process (ASP).

[0192]

[0190] Next, the upper surface of the core component 211 can be joined to the lower surface of the upper component 212. In this case as well, this joining process may be diffusion bonding or penetration bonding.

[0193]

[0191] Once all components 210, 211, and 212 are joined together, several structuring processes can be performed to form desired features on the upper surface of the upper component 212. For example, an advanced structuring process can be used to form multiple burrs 241 and seals 231, 232, 233, and 234 that are positioned on the upper surface of the upper component 212. Furthermore, electrical discharge machining can be used to form various holes on the upper surface of the upper component 212 that extend downward into the substrate support 200, such as a first extraction opening 260 and a first passage 270. Electrical discharge machining can also be used to form other holes in the substrate support 200, such as a clamp opening 264.

[0194]

[0192] Once the structuring process is complete, other openings such as the periphery opening 262, the second extraction opening 261, and the multifunctional opening 263 can be formed. These openings 261, 262, and 263 can be formed using techniques such as laser drilling.

[0195]

[0193] Next, a number of finishing processes can be performed to ensure that the flatness of the substrate support 200 satisfies the required tolerance. Such finishing processes may include polishing.

[0196]

[0194] Once the finishing process is completed, 3D measurements of the substrate support 200 can be taken to evaluate its geometry and ensure that its dimensions are within the tolerances set by the specifications.

[0197]

[0195] Any final coating and assembly steps can be performed to complete the manufacturing process.

[0198]

[0196] This manufacturing process is merely an example of how substrate supports 200, 400, and 500 can be manufactured according to the present invention, and it is also possible to use other techniques instead, or to perform these steps in a different order. For example, hard machining processes (i.e., CNC, electrical discharge machining, and advanced structuring processes) may be performed before joining the various components together.

[0199]

[0197] The gas supplied through the openings, for example, through the multifunctional opening 263 in the loaded state and through the peripheral opening 262 in the clamped state, is not particularly limited. For example, clean dry air (CDA), humidified air, or N2 may be supplied. Preferably, humidified air is supplied, especially through the peripheral opening 262 in the loaded state. This is because CDA with very low humidity may cause evaporation of the immersion fluid on the outer seal 231, which creates a large thermal load on the outer seal 231. This may cause temporary structural deformation of the substrate support 200, which may lead to an overlay penalty. Humidified air means that less immersion fluid evaporates from around the outer seal 231, thus reducing the thermal load.

[0200]

[0198] The present invention may provide a lithography apparatus. The lithography apparatus may have any / all of the other features or components of the lithography apparatus described above. For example, the lithography apparatus may optionally include at least one of the following: a radiation source SO, an illumination system IL, a projection system PS, a substrate table WT, etc.

[0201]

[0199] Specifically, the lithography apparatus may include a projection system PS configured to project a radiation beam B toward a region of the surface of the substrate W. The lithography apparatus may further include a substrate support 200 as described in any of the above embodiments and modifications.

[0202]

[0200] In this disclosure, the terms “submerged liquid” and “submerged fluid” are used interchangeably.

[0203]

[0201] While this text specifically refers to the use of lithography equipment in the manufacture of ICs, it should be understood that lithography equipment described herein may have other applications. Possible other applications include the manufacture of integrated optical systems, guidance and detection patterns for magnetic domain memory, flat panel displays, liquid crystal displays (LCDs), thin-film magnetic heads, and the like.

[0204]

[0202] Where permitted by context, embodiments of the present invention may be implemented in hardware, firmware, software, or any combination thereof. Embodiments of the present invention may also be implemented as instructions stored in a machine-readable medium that can be read and executed by one or more processors. A machine-readable medium may include any mechanism for storing or transmitting information in a form readable by a machine (e.g., a computing device). For example, a machine-readable medium may include read-only memory (ROM), random access memory (RAM), magnetic storage media, optical storage media, flash memory devices, propagating signals of electrical, optical, acoustic or other forms (e.g., carrier waves, infrared signals, digital signals, etc.), and others. Furthermore, firmware, software, routines, and instructions may be described herein as performing specific actions. However, it should be understood that such descriptions are merely for convenience, and that such actions actually result from a computing device, processor, controller, or other device that executes the firmware, software, routines, instructions, etc., and that in execution, actuators or other devices may interact with the material world.

[0205]

[0203] Although embodiments of the present invention are specifically referred to in the context of lithography apparatus in this text, embodiments of the present invention may be used in other apparatuses. Embodiments of the present invention may form part of a mask inspection apparatus, a metrology apparatus, or any apparatus for measuring or processing objects such as wafers (or other substrates) or masks (or other patterning devices). These apparatuses may generally be referred to as lithography tools.

[0206]

[0204] Although the above has specifically referred to the use of embodiments of the present invention in the context of photolithography, it will be understood that the present invention is not limited to photolithography where permitted in the context.

[0207]

[0205] Although specific embodiments of the present invention have been described above, it will be understood that the present invention can be implemented in ways other than those described. The above description is for illustrative purposes only and is not limiting. Accordingly, it will be apparent to those skilled in the art that modifications to the described invention can be made without departing from the following claims.

Claims

1. A substrate support configured to support a substrate, comprising an upper component, a core component, and a lower component, A first opening is formed on the upper surface of the upper component. A first passage communicating with the first opening is defined in the upper component and the core component. The core component and the lower component define a first extraction channel that communicates with the first passage. A substrate support in which a first adjustment channel is defined by the core component and the lower component.

2. The substrate support according to claim 1, further comprising: the upper component being joined to the core component; the core component being joined to the lower component; and / or the upper component being joined to the core component by diffusion bonding or penetration bonding; and / or the core component being joined to the lower component by diffusion bonding or penetration bonding; and / or a second extraction channel configured to extract fluid, located radially inward of the first extraction channel.

3. A second passage communicating with the second extraction channel is defined in the upper component and the core component, A second opening communicating with the second passage is formed on the upper surface of the upper component, and / or The second extraction channel is defined by the core component and the lower component, or The substrate support according to claim 2, wherein the second extraction channel is defined by the upper component and the core component, and preferably the first extraction channel and the second extraction channel are configured to overlap radially.

4. The second opening is located radially inward of the first opening, and / or the second passage forms a substantially L-shape, and / or The second passage is, A first vertical portion extends substantially perpendicular to the upper surface of the upper component and communicates with the second opening, A horizontal portion extending substantially horizontally with respect to the upper surface of the upper component and communicating with the vertical portion of the second passage, The substrate support according to claim 3, comprising: a second vertical portion extending substantially perpendicular to the upper surface of the upper component and communicating with the horizontal portion and the second extraction channel of the second passage, preferably the horizontal portion of the second passage having a first wall formed by the upper component and a second wall formed by the core component.

5. The present invention further comprises a multifunctional channel configured to supply or extract gas, preferably the horizontal portion of the second passage having a first wall formed by the upper component and a second wall formed by the core component, and / or A third passage communicating with the multi-functional channel is defined in the upper component and the core component, A third opening communicating with the third passage is formed on the upper surface of the upper component, and / or The multi-function channel is defined by the core component and the sub-component, and / or The third opening is located radially inward of the second opening, and / or The third passage substantially forms an L-shape, and / or, The third passage mentioned above is, A first vertical portion extends substantially perpendicular to the upper surface of the upper component and communicates with the third opening, A horizontal portion extending substantially horizontally with respect to the upper surface of the upper component and communicating with the vertical portion of the third passage, A substrate support according to any one of claims 2 to 4, comprising: a second vertical portion extending substantially perpendicular to the upper surface of the upper component and communicating with the horizontal portion of the third passage and the multifunctional channel, preferably the horizontal portion of the third passage having a first wall formed by the upper component and a second wall formed by the core component.

6. The first adjustment channel is located radially outward of the multifunctional channel and radially inward of the second extraction channel, and / or further comprises an ambient channel that is in fluid communication with the ambient pressure, preferably the ambient channel is located radially inward of the multifunctional channel, and / or A fourth passage communicating with the surrounding channel and defined in the upper component and the core component, The present invention further comprises a fourth opening formed on the upper surface of the upper component, which communicates with the fourth passage, preferably, The surrounding channel is defined by the core component and the lower component, or The surrounding channel is defined by the core component and the upper component, preferably, The substrate support according to claim 5, wherein the multifunctional channel and the peripheral channel are configured to overlap in the radial direction.

7. The fourth opening is radially inward of the second opening and radially outward of the third opening, and / or the fourth passage substantially forms an L shape, and / or The aforementioned fourth passage is, A first vertical portion extends substantially perpendicular to the upper surface of the upper component and communicates with the fourth opening, A horizontal portion extending substantially horizontally with respect to the upper surface of the upper component and communicating with the vertical portion of the fourth passage, It includes, preferably, a second vertical portion extending substantially perpendicular to the upper surface of the upper component and communicating with the horizontal portion and the surrounding channel of the fourth passage, The horizontal portion of the fourth passage has a first wall formed by the upper component and a second wall formed by the core component, and / or The system further comprises a second adjustment channel located radially inward of the surrounding channel, and / or The substrate support according to claim 6, further comprising a second adjustment channel located radially inward of the multifunctional channel and radially outward of the surrounding channel.

8. The radial distance between the radially inner wall of the second extraction channel and the radially outer wall of the first adjustment channel is less than 5 mm, preferably less than 2 mm, more preferably less than 1.6 mm, but greater than 1 mm, preferably greater than 1.4 mm, and / or, the radial distance between the radially inner wall of the first extraction channel and the radially outer wall of the second extraction channel is less than 5 mm, preferably less than 2 mm, more preferably less than 1.6 mm, but greater than 1 mm, preferably greater than 1.4 mm, and / or, The second extraction channel is in fluid communication with the first regulating channel, and / or The second extraction channel is in fluid communication with the first extraction channel, or The substrate support according to any one of claims 2 to 7, further comprising a fluid extraction recess extending in the circumferential direction of the substrate support, wherein the second extraction opening is configured to extract fluid from the fluid extraction recess, and the first adjustment channel is in fluid communication with the fluid extraction recess.

9. The substrate support according to any one of claims 1 to 8, wherein the radial distance between the radial edge of the substrate support and the radially outer wall of the first extraction channel is less than 5 mm, preferably less than 2 mm, more preferably less than 1.5 mm, but greater than 1 mm, more preferably greater than 1.3 mm, and / or one or more of the channels are cavities extending circumferentially from the substrate support, and / or the first opening is defined by a groove extending circumferentially from the substrate support, the groove being provided as a recess in the upper surface of the substrate support.

10. The substrate support according to claim 8, wherein the second extraction channel is in fluid communication with the first adjustment channel via a first connecting passage, and / or the second extraction channel is in fluid communication with the first extraction channel via a second connecting passage, and / or the first adjustment channel is in fluid communication with the fluid extraction recess via a third connecting passage, preferably the first adjustment channel is in fluid communication with the fluid extraction recess via a third connecting passage.

11. The substrate support is configured such that, when the substrate is supported by the substrate support, the groove is located radially outward from the radial edge of the substrate, and / or the cross-sectional area of ​​the groove is 1 mm ２ More preferably 3 mm ２ More preferably 5 mm ２ The substrate support according to claim 9 or 10, wherein the first passage is connected to the first fluid extraction groove at the most downstream point in the first fluid extraction groove, and / or a plurality of flow limiting members are arranged in the groove.

12. The substrate support according to any one of claims 1 to 11, wherein the lower component includes a plurality of protrusions configured to support the substrate support on a stage, and / or a plurality of flow limiting members are disposed in the grooves, and / or the upper component, the core component, and the lower component are formed of SiSiC, and / or the substrate support is configured for use in a lithography apparatus.

13. A lithography apparatus comprising a substrate support according to any one of claims 1 to 12.

14. A method for supporting a substrate, comprising the use of a substrate support according to any one of claims 1 to 12.

15. A method for manufacturing a device, comprising a method for supporting a substrate as described in claim 14.

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