Fluid handling system, method and lithographic apparatus

Abstract

A fluid handling system for a lithographic apparatus is disclosed herein. The fluid handling system is configured to confine an immersion fluid in a liquid confinement space between a part of a projection system in a lithographic apparatus and a surface of a substrate such that a radiation beam projected from the projection system can irradiate the surface of the substrate by passing through the immersion fluid. The fluid handling system comprises a meniscus control surface for controlling the movement of a meniscus of the immersion fluid. In a first operating state, the meniscus control surface is configured to hold the meniscus of the immersion fluid substantially stationary between the meniscus control surface and the surface of the substrate, and in a second operating state, the meniscus control surface is configured to allow movement of the meniscus of the immersion fluid.

Description

Technical Field

[0001] [Cross - reference to related applications] This application claims priority to European application 22183583.8 filed on July 7, 2022, the entire content of which is incorporated herein by reference in its entirety.

[0002] [Technical Field] The present invention relates to fluid handling systems and device manufacturing methods. The present invention also relates to lithographic apparatuses.

Background Art

[0003] A lithographic apparatus is a device 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 may project a pattern of a patterning device (e.g., a mask), often also 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 onto the target portion, and so - called scanners, in which each target portion is irradiated by scanning the pattern in a predetermined direction ("scan" direction) through a radiation beam while simultaneously scanning the substrate parallel or non - parallel to this direction.

[0004] As semiconductor manufacturing processes continue to advance, following the trend generally known as "Moore's Law," the number of functional elements such as transistors per device has steadily increased over the past few decades while the dimensions of circuit elements have been continuously reduced. The semiconductor industry is pursuing technologies that enable the generation of ever-smaller features so as not to lag behind Moore's Law. To project a pattern onto a substrate, a lithographic apparatus may use electromagnetic radiation. The wavelength of this radiation determines the minimum size of the features formed on the substrate. Typical wavelengths currently in use are 365 nm (i-line), 248 nm, 193 nm, and 13.5 nm.

[0005] Further improvements in the resolution of smaller features may be achieved by providing an immersion fluid such as water, which has a relatively high refractive index, on the substrate during exposure. The effect of the immersion fluid is to enable imaging of smaller features because the exposure radiation in the fluid has a shorter wavelength than in air. The effect of the immersion fluid is also that it increases the effective numerical aperture (NA) of the system and also increases the depth of focus.

SUMMARY OF THE INVENTION

PROBLEMS TO BE SOLVED BY THE INVENTION

[0006] The immersion fluid may be restricted by a fluid handling structure to a local area between the projection system of the lithographic apparatus and the substrate. The use of such an immersion fluid can lead to the presence of droplets on the surface of the substrate. Such droplets can cause dry spots on the substrate and, when a droplet hits the meniscus of the immersion liquid, can lead to the formation of bubbles by the gas trapped in the immersion liquid, which can be problematic. Bubbles in the immersion liquid can lead to defects printed on the substrate. The possibility of such bubbles being introduced can be reduced by reducing the relative speed of the substrate, but this limits the throughput of the lithographic apparatus.

[0007] An object of the present invention is to provide a fluid handling system and method in which means for increasing throughput and / or reducing defects on a substrate are taken.

Means for Solving the Problem

[0008] According to a first aspect of the present invention, there is provided a fluid handling system for a lithographic apparatus. The system is configured to confine an immersion fluid in a liquid confinement space between a part of a projection system in the lithographic apparatus and the surface of a substrate such that a radiation beam projected from the projection system can irradiate the surface of the substrate by passing through the immersion fluid, and comprises a meniscus control surface for controlling the movement of the meniscus of the immersion fluid. In a first operating state, the meniscus control surface is configured to hold the meniscus of the immersion fluid substantially stationary between the meniscus control surface and the surface of the substrate. In a second operating state, the meniscus control surface is configured to allow the movement of the meniscus of the immersion fluid.

[0009] According to a second aspect of the present invention, there is provided a fluid handling system for a lithographic apparatus. The system is configured to confine an immersion fluid in a liquid confinement space between a part of a projection system in the lithographic apparatus and the surface of a substrate such that a radiation beam projected from the projection system can irradiate the surface of the substrate by passing through the immersion fluid, and comprises a meniscus control surface and a take-out portion configured to take out the immersion fluid together. The meniscus control surface is configured to support the meniscus of the immersion fluid between the meniscus control surface and the surface of the substrate under a first operating state and a second operating state. In the first operating state, the meniscus is fixed to the meniscus control surface. In the second operating state, the meniscus is movable along the meniscus control surface.

[0010] According to a third aspect of the invention, a fluid handling system for a lithographic apparatus is provided. The system is configured to confine an immersion fluid in a liquid confinement space between a part of a projection system in a lithographic apparatus and a surface of a substrate such that a radiation beam projected from the projection system can irradiate the surface of the substrate by passing through the immersion fluid, and comprises a first extraction part and a second extraction part both configured to extract the immersion fluid, and a meniscus control surface between the first extraction part and the second extraction part configured to extract the immersion fluid, the meniscus control surface being configured to support a meniscus of the immersion liquid between the surface of the meniscus control surface and the surface of the substrate.

[0011] According to a fourth aspect of the invention, a lithographic apparatus comprising the fluid handling system of the first to third aspects is provided.

[0012] According to a fifth aspect of the invention, a device manufacturing method in a lithographic apparatus is provided, the lithographic apparatus having a substrate holder configured to hold a substrate, a projection system configured to project a radiation beam onto the substrate held by the substrate holder, and a fluid handling system according to any of the first to third aspects. The method comprises using the fluid handling system to confine an immersion fluid in a space between at least a part of the fluid handling system and a surface of the substrate, projecting a patterned radiation beam onto the substrate through the immersion fluid in the space, supporting a meniscus of the immersion fluid between the meniscus control surface or a damper of the fluid handling system and the substrate, and driving the substrate in a scan direction substantially perpendicular to the propagation direction of the radiation beam. In a first operating state, the meniscus control surface is configured to hold the meniscus of the immersion fluid substantially stationary between the meniscus control surface and the surface of the substrate, and in a second operating state, the meniscus control surface is configured to allow movement of the meniscus of the immersion fluid with respect to the meniscus control surface.

[0013] According to a sixth aspect of the invention, a fluid handling system for a lithographic apparatus is provided. The system is configured to confine an immersion fluid in a liquid confinement space between a part of a projection system in a lithographic apparatus and a surface of a substrate, such that a radiation beam projected from the projection system can irradiate the surface of the substrate by passing through the immersion fluid, and comprises an electro-wetting structure, the electro-wetting structure comprising one or more electrodes arranged to apply an electro-wetting effect to at least a part of the substrate facing a surface of the fluid handling system, the one or more electrodes of the electro-wetting structure being controllable to vary a contact angle and / or a contact line of a meniscus of the immersion fluid.

[0014] According to a seventh aspect of the invention, a lithographic apparatus is provided comprising the fluid handling system of the sixth aspect.

[0015] Further embodiments, features and advantages of the invention, and the structure and operation of various embodiments, features and advantages of the invention, are described in detail below with reference to the accompanying drawings.

Brief Description of the Drawings

[0016] In the following, embodiments of the invention are described by way of example only, with reference to the following accompanying schematic drawings in which corresponding reference symbols represent corresponding parts.

[0017] FIG. 1 shows a schematic overview of a lithographic apparatus.

[0018] FIGS. 2a, 2b, 2c and 2d show in cross-section two different versions of a fluid handling system having different features illustrated on the left and right sides of each version, which may extend circumferentially.

[0019] FIGS. 3a and 3b schematically show a part of a known fluid handling system in a first and a second operating state, respectively.

[0020] Figure 4 schematically shows a part of the fluid handling system according to the first embodiment.

[0021] Figure 5 schematically shows a part of the fluid handling system according to the second embodiment.

[0022] Figures 6a and 6b schematically show a part of the fluid handling system according to the third embodiment.

[0023] The features shown are not necessarily to scale and are not limited to the sizes and / or arrangements shown. The figures are understood to include optional features that are not essential to the invention. Further, not all features of the device are shown in each of the figures, and the figures may show only some of the relevant components in describing a particular feature.

Mode for Carrying Out the Invention

[0024] In this document, the terms "radiation" and "beam" are used to encompass all types of electromagnetic radiation including ultraviolet radiation (e.g., having wavelengths of 365, 248, 193, 157, or 126 nm).

[0025] The terms "reticle", "mask", or "patterning device" used in this text may be broadly interpreted to represent a general patterning device that can be used to impart a patterned cross-section corresponding to a pattern to be generated in a target portion of a substrate to an incident radiation beam. The term "light valve" may also be used in this context. Examples of other such patterning devices include programmable mirror arrays and programmable LCD arrays in addition to classical masks (transmission or reflection type, binary type, phase shift type, hybrid type, etc.).

[0026] Figure 1 schematically shows a lithographic apparatus. The lithographic apparatus comprises an illumination system (also referred to as an illuminator) IL configured to condition a radiation beam B (e.g., UV radiation or DUV radiation), a mask support (e.g., a mask table) MT configured to support a patterning device (e.g., a mask) MA and connected to a first positioner PM configured to accurately position the patterning device MA in accordance with certain parameters, a substrate support (e.g., a substrate table) WT configured to hold a substrate (e.g., a wafer coated with a resist) W and connected to a second positioner PW configured to accurately position the substrate support WT in accordance with certain parameters, and a projection system (e.g., a refractive projection lens system) PS configured to project a pattern formed in the radiation beam B by the patterning device MA onto a target portion C (e.g., including one or more dies) of the substrate W. A controller 500 controls the overall operation of the apparatus. The controller 500 may be a central control system or a system of a plurality of other sub-controllers within various subsystems of the lithographic apparatus.

[0027] During operation, the illumination system IL receives the radiation beam B from a radiation source SO, e.g., via a 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 for directing, shaping and / or controlling the radiation, or any combination thereof. The illuminator IL may be used to condition the radiation beam B such that it has a desired spatial and angular intensity distribution in the plane and in the cross-section of the patterning device MA.

[0028] As used herein, the term "projection system" PS shall be construed broadly to encompass various types of projection systems, including refractive, reflective, catadioptric, anamorphic, magnetic, electromagnetic and / or electrostatic optical systems, or any combination thereof, that are appropriate for the exposure radiation in use and / or other factors such as the use of immersion liquid or vacuum. The use of the term "projection lens" herein may be construed synonymously with the more general term "projection system" PS.

[0029] The lithographic apparatus may be of a type in which at least a portion of the substrate W is covered by an immersion liquid such as water having a relatively high refractive index, to fill the immersion space 11 between the projection system PS and the substrate W (also referred to as immersion lithography). More information on immersion techniques is given in US6,952,253, which is incorporated herein by reference.

[0030] The lithographic apparatus may be of a type having two or more substrate supports WT (also referred to as "dual stage"). In such a "multi-stage" apparatus, the substrate supports WT may be used in parallel and / or preparatory steps for a subsequent exposure of the substrate W may be carried out on the substrate W disposed on one of the substrate supports WT while the other substrate W on the other substrate support WT is being used to expose a pattern on another substrate.

[0031] In addition to the substrate support WT, the lithographic apparatus may comprise a measurement stage (not shown). The measurement stage is provided to hold a sensor and / or a cleaning device. The sensor may be provided to measure characteristics of the projection system PS or of the radiation beam B. The measurement stage may hold a plurality of sensors. The cleaning device may be provided to clean parts of the lithographic apparatus, for example parts of the projection system PS or parts of the system providing the immersion liquid. The measurement stage may move under the projection system PS when the substrate support WT is away from the projection system PS.

[0032] During operation, the radiation beam B is incident on a patterning device such as a mask MA held on a mask support MT, and is patterned by a pattern (design layout) existing on the patterning device MA. The radiation beam B that has passed through the mask MA passes through a projection system PS that focuses the beam on a target portion C of the substrate W. By means of a second positioner PW and a position measurement system IF, the substrate support WT can be accurately driven, for example, to place different target portions C at the focusing and alignment positions in the path of the radiation beam B. Similarly, a first positioner PM and other suitable position sensors (not explicitly shown in FIG. 1) may be used to accurately position the patterning device MA with respect to the path of the radiation beam B. The patterning device MA and the substrate W may 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 they may also be arranged in the space between the target portions. Substrate alignment marks P1, P2 arranged between the target portions C are known as scribe line alignment marks.

[0033] To clarify the invention, a Cartesian coordinate system is used. The Cartesian coordinate system has three axes, namely, the x-axis, the y-axis, and the z-axis. Each of the three axes is orthogonal to the other two axes. Rotation about the x-axis is denoted as Rx rotation. Rotation about the y-axis is denoted as Ry rotation. Rotation about the z-axis is denoted as Rz rotation. The x-axis and the y-axis define a horizontal plane, and the z-axis defines a vertical direction. The Cartesian coordinate system is not intended to limit the invention and is used only for the purpose of explanation. Instead, another coordinate system such as a cylindrical coordinate system may be used to clarify the invention. For example, the direction of the Cartesian coordinate system may be different such that the z-axis has a component along the horizontal plane.

[0034] Immersion technology has been introduced into lithography systems to enable higher resolution of smaller features. In an immersion lithography apparatus, a liquid layer of an immersion liquid having a relatively high refractive index is interposed in an immersion space 11 between a projection system PS of the apparatus (through which a pattern-formed beam is projected toward a substrate W) and the substrate W. The immersion liquid covers at least a part of the substrate W under the final element of the projection system PS. Thus, at least a part of the substrate W during exposure is immersed in the immersion liquid.

[0035] In commercialized immersion lithography, the immersion liquid is water. The water is typically high-purity distilled water such as ultrapure water (UPW) commonly used in semiconductor manufacturing plants. In an immersion system, the UPW is frequently purified and may have to undergo additional processing steps before being supplied as the immersion liquid to the immersion space 11. Other liquids other than water having a high refractive index, such as hydrocarbons like fluorocarbons and / or aqueous solutions, can also be used as the immersion liquid. Furthermore, other fluids other than liquids are also expected to be used in immersion lithography.

[0036] Reference is made herein to localized immersion in which the immersion liquid in use is restricted to the immersion space 11 between the final element 100 and the surface facing the final element 100. The opposing surface is the surface of the substrate W or the surface of a support stage (or substrate support WT) on the same plane as the surface of the substrate W (note that references to the surface of the substrate W in the following text represent, in addition or in place of, the surface of the substrate support WT as well, and vice versa). A fluid handling structure 12 present between the projection system PS and the substrate support WT is used to restrict the immersion liquid to the immersion space 11. The immersion space 11 filled with the immersion liquid is smaller than the outermost surface of the substrate W in plan view, and during movement of the substrate W and the substrate support WT below, the immersion space 11 remains substantially stationary with respect to the projection system PS.

[0037] Other immersion systems are also envisioned, such as non-restricted immersion systems (so-called "all-wet" immersion systems) and bath-type immersion systems. In a non-restricted immersion system, the immersion liquid covers more than the lower surface of the final element 100. The liquid outside the immersion space 11 exists as a thin liquid film. The liquid may cover the entire surface of the substrate W or the substrate W and the substrate support WT on the same plane as the substrate W. In a bath-type system, the substrate W is completely immersed in the bath of the immersion liquid.

[0038] The fluid handling structure 12 is a structure that restricts the immersion liquid to the immersion space 11 by supplying the immersion liquid to the immersion space 11 and removing the immersion liquid from the immersion space 11. It includes features that are part of a fluid supply system. The arrangement disclosed in PCT Patent Application Publication No. WO99 / 49504 is an initial fluid handling structure with pipes that supply or recover the immersion liquid in the immersion space 11 and operate in response to the relative movement of the stage under the projection system PS. In a newer design, the fluid handling structure extends along at least a part of the boundary of the immersion space 11 between the final element 100 of the projection system PS and the substrate support WT or the substrate W, and partially defines the immersion space 11.

[0039] The fluid handling structure 12 may have different functional options. Each function may be obtained from corresponding features that enable the fluid handling structure 12 to realize that function. The fluid handling structure 12 may be represented by many different terms representing functions, such as a barrier member, a seal member, a fluid supply system, a fluid removal system, a liquid restriction structure, etc.

[0040] The fluid handling structure 12 as a barrier member is a barrier against the flow of the immersion liquid from the immersion space 11. The structure as a liquid restriction structure restricts the immersion liquid to the immersion space 11. The sealing feature of the fluid handling structure 12 as a seal member forms a seal for restricting the immersion liquid to the immersion space 11. The sealing feature may include an additional gas flow from an opening on the surface of a seal member such as a gas knife.

[0041] In one embodiment, the fluid handling structure 12 may supply an immersion fluid as a fluid supply system.

[0042] In one embodiment, the fluid handling structure 12 may at least partially restrict the immersion fluid as a fluid restriction system.

[0043] In one embodiment, the fluid handling structure 12 may provide a barrier to the immersion fluid as a barrier member such as a fluid restriction structure.

[0044] In one embodiment, the fluid handling structure 12 may generate or use a gas flow, for example, to assist in controlling the immersion fluid flow and / or position.

[0045] The gas flow may form a seal for restricting the immersion fluid, and the fluid handling structure 12 may be represented as a seal member. Such a seal member may be a fluid restriction structure.

[0046] In one embodiment, an immersion liquid is used as the immersion fluid. In this case, the fluid handling structure 12 may be a liquid handling system. With reference to the above description, references to features defined for the fluid in these paragraphs are understood to include features defined for the liquid.

[0047] The lithographic apparatus has a projection system PS. During exposure of the substrate W, the projection system PS projects a patterned beam of radiation onto the substrate W. In order to reach the substrate W, the path of the radiation beam B passes through an immersion liquid restricted by the fluid handling structure 12 between the projection system PS and the substrate W. The projection system PS has a lens element that contacts the immersion liquid at the end of the beam path. This lens element that contacts the immersion liquid may be referred to as the "final lens element" or "final element". The final element 100 is at least partially surrounded by the fluid handling structure 12. The fluid handling structure 12 may restrict the immersion liquid below and above the lower and opposing surfaces of the final element 100.

[0048] Figures 2a, 2b, 2c, and 2d show different features that may be present in various fluid handling systems. The design may share some of the same features as Figures 2a, 2b, 2c, and 2d, unless otherwise specified. The features described herein may be selected individually or in combination, as shown or as required. The figures show different versions of a fluid handling system having different features illustrated on the left and right sides, which may extend around the entire circumference. Thus, for example, the fluid handling system may have the same features extending around the entire circumference. For example, the fluid handling system may have only the features on the left side of Figure 2a, or the right side of Figure 2a, or the left side of Figure 2b, or the right side of Figure 2b, or the left side of Figure 2c, or the right side of Figure 2c, or the left side of Figure 2d, or the right side of Figure 2d. Alternatively, any combination of features from these figures may be provided at different circumferential positions in the fluid handling system. The fluid handling system may comprise various fluid handling structures 12 described below.

[0049] Figure 2a shows a fluid handling structure 12 around the bottom surface of the final element 100. The final element 100 has a frustum of a cone shape. The frustum of a cone shape has a flat bottom surface and a conical surface. The frustum of a cone shape projects from a flat surface and has a flat bottom surface. The flat bottom surface is the optically active portion of the bottom surface of the final element 100 through which the radiation beam B may pass. The final element 100 may have a coating 30. The fluid handling structure 12 surrounds at least a part of the frustum of a cone shape. The fluid handling structure 12 has an inner surface facing the conical surface of the frustum of a cone shape. The inner surface and the conical surface may have complementary shapes. The top surface of the fluid handling structure 12 may be substantially flat. The fluid handling structure 12 may fit around the frustum of a cone shape of the final element 100. The bottom surface of the fluid handling structure 12 may be substantially flat, and during use, the bottom surface may be parallel to the opposing surface of the substrate support WT and / or the substrate W. Thus, the bottom surface of the fluid handling structure 12 may be represented as the surface facing the surface of the substrate W. The distance between the bottom surface and the opposing surface may be in the range of 20 to 500 micrometers, desirably in the range of 70 to 200 micrometers.

[0050] The fluid handling structure 12 extends closer to the opposing surface of the substrate W and the substrate support WT than the final element 100. The immersion space 11 is thus defined between the inner surface of the fluid handling structure 12, the flat surface of the frustum of a cone portion, and the opposing surface. During use, the immersion space 11 is filled with an immersion liquid. The immersion liquid fills at least a part of the buffer space (in one embodiment, at least a part of the space between the complementary inner surface and the conical surface) between the complementary surfaces between the final element 100 and the fluid handling structure 12.

[0051] The immersion liquid is supplied to the immersion space 11 through an opening formed on the surface of the fluid handling structure 12. The immersion liquid may be supplied through a supply opening 20 on the inner surface of the fluid handling structure 12. Alternatively or additionally, the immersion liquid is supplied from a lower supply opening 23 formed on the bottom surface of the fluid handling structure 12. The lower supply opening 23 may surround the path of the radiation beam B and may be formed as a series of openings in an array or a single slit. The immersion liquid is supplied to fill the immersion space 11, and the flow through the immersion space 11 under the projection system PS becomes laminar. The supply of the immersion liquid from the lower supply opening 23 additionally prevents bubbles from entering the immersion space 11. This supply of the immersion liquid may function as a liquid seal.

[0052] The immersion liquid may be recovered from a recovery opening 21 formed on the inner surface. The recovery of the immersion liquid through the recovery opening 21 may be performed by applying a negative pressure. The recovery through the recovery opening 21 may be the result of the flow rate of the immersion liquid through the immersion space 11. Alternatively, the recovery may be both results. The recovery opening 21 may be disposed on the opposite side of the supply opening 20 in plan view. Additionally or alternatively, the immersion liquid may be recovered through an overflow recovery portion 24 disposed on the top surface of the fluid handling structure 12. The functions of the supply opening 20 and the recovery opening 21 may be interchanged (i.e., the liquid flow direction is reversed). In this case, the flow direction can be changed according to the relative movement of the fluid handling structure 12 and the substrate W.

[0053] Additionally or alternatively, the immersion liquid may be recovered from below the fluid handling structure 12 through a recovery opening 25 formed on its bottom surface. The recovery opening 25 may function to hold the meniscus 33 of the immersion liquid against the fluid handling structure 12. The meniscus 33 is formed between the fluid handling structure 12 and the opposing surface and functions as a boundary between the liquid space and the external gas environment. The recovery opening 25 may be a porous plate that may recover the immersion liquid with substantially single-phase flow. The recovery opening on the bottom surface may also be a series of pinning openings 32 through which the immersion liquid is recovered. The pinning openings 32 may recover the immersion liquid with two-phase flow.

[0054] Optionally, a gas knife opening 26 is provided radially outward of the inner surface of the fluid handling structure 12. The gas may be supplied through the gas knife opening 26 at an increased speed to assist in liquid confinement of the immersion liquid in the immersion space 11. The supplied gas may be wet and may substantially contain carbon dioxide. A gas recovery opening 28 for recovering the gas supplied through the gas knife opening 26 is provided radially outward of the gas knife opening 26.

[0055] Additional openings, such as those open to the atmosphere, a gas source, or a vacuum, may be present on the bottom surface of the fluid handling structure 12, i.e., the surface of the fluid handling structure 12 facing the substrate W. An example of such an additional opening 50 of this option is indicated by the dotted line on the right side of FIG. 2a. As shown, the additional opening 50 may be a supply or extraction part as indicated by the bidirectional arrow. For example, when configured as a supply part, the additional opening 50 may be connected to a liquid supply part, a gas supply part, or any other supply part. Alternatively, when configured as an extraction part, the additional opening 50 may be used to extract fluid and may be connected to, for example, the atmosphere, a gas source, or a vacuum. For example, at least one additional opening 50 may be present between the gas knife opening 26 and the gas recovery opening 28, and / or between the pinning opening 32 and the gas knife opening 26.

[0056] Two different versions of the fluid handling structures 12 on the left and right sides of FIG. 2a hold the meniscus 33. The version of the fluid handling structure 12 on the right side of FIG. 2a may hold the meniscus 33 at a position substantially fixed relative to the final element 100 due to the fixed position of the pinning opening 32. The version of the fluid handling structure 12 on the left side of FIG. 2a may hold the meniscus 33 below the recovery opening 25, and the meniscus 33 may move along the length and / or width of the recovery opening 25. To direct the radiation beam B to both ends of the substrate W during exposure, the substrate support WT supporting the substrate W is driven relative to the projection system PS. To maximize the output of the substrate W exposed by the lithographic apparatus, the substrate support WT (and also the substrate W) is driven as fast as possible. However, there is a critical relative speed (often expressed as the critical scan speed), beyond which the meniscus 33 between the fluid handling structure 12 and the substrate W becomes unstable. An unstable meniscus 33 is associated with a greater risk, for example, of losing the immersion liquid in the form of one or more droplets. Furthermore, an unstable meniscus 33 is associated with a greater risk of introducing air bubbles into the immersion liquid, especially when the limited immersion liquid exceeds the edge of the substrate W.

[0057] Droplets present on the surface of the substrate W can impose a heat load and can cause defects. Droplets can evaporate and leave a drying stain, can move and carry contaminants such as particles, can collide with a larger mass of immersion liquid and introduce gas bubbles into the larger mass, and can evaporate and impose a heat load on the surface on which it is disposed. Such a heat load can be a cause of distortion and / or a source of positioning error when the surface is associated with the positioning of components of the lithographic apparatus relative to the substrate W during imaging. Thus, the formation of droplets on the surface is undesirable. To avoid the formation of such droplets, the speed of the substrate support WT is limited to the critical scan speed at which the meniscus 33 is stable. This limits the throughput of the lithographic apparatus.

[0058] The left side of the fluid handling system in FIG. 2a may include a spring 60. The spring 60 may be an adjustable passive spring configured to exert a biasing force in the direction of the substrate W on the fluid handling structure 12. Thus, the spring 60 can be designed to control the height of the fluid handling structure 12 above the substrate W. Such an adjustable passive spring is described in US7,199,874, which is hereby incorporated by reference in its entirety. Other biasing devices (e.g., those using electromagnetic force) are also suitable. The spring 60 is shown optionally with the left side of FIG. 2a, but it does not have to be included with the other features on the left side of FIG. 2a. Although the spring 60 is not shown in any other figures, it can be included with various other fluid handling systems described with respect to FIGS. 2a, 2b, 2c, or 2d.

[0059] FIG. 2b shows two different versions of the fluid handling structure 12 on the left and right sides that allow the movement of the meniscus 33 relative to the final element 100. The meniscus 33 may move in the direction of the moving substrate W. This can reduce the relative speed between the meniscus 33 and the moving substrate W, leading to improved stability and a reduced risk of collapse of the meniscus 33. By increasing the speed of the substrate W at which the meniscus 33 collapses, the movement of the substrate W below the projection system PS can be accelerated. Thus, the throughput is increased.

[0060] The features shown in FIG. 2b that are common to FIG. 2a share the same reference numerals. The fluid handling structure 12 has an inner surface complementary to a frustum-shaped conical surface. The bottom surface of the fluid handling structure 12 is closer to the opposing surface than the flat bottom surface of the frustum shape.

[0061] The immersion liquid is supplied to the immersion space 11 through a supply opening 34 formed in the inner surface of the fluid handling structure 12. The supply opening 34 is disposed at the bottom side of the inner surface (e.g., below the bottom surface of the frustum shape). The supply opening 34 is disposed around the inner surface, away from the path of the radiation beam B.

[0062] The immersion liquid is recovered from the immersion space 11 through the recovery opening 25 on the bottom surface of the fluid handling structure 12. Since the opposing surface moves below the fluid handling structure 12, the meniscus 33 may move on the surface of the recovery opening 25 in the same direction as the movement of the opposing surface. The recovery opening 25 may be formed of a porous member. The immersion liquid may be recovered in a single phase. The immersion liquid may be recovered in a two-phase flow. The two-phase flow is received in the chamber 35 within the fluid handling structure 12 and separated into a liquid and a gas. The liquid and the gas are recovered from the chamber 35 through separate channels 36, 38.

[0063] The inner peripheral portion 39 of the bottom surface of the fluid handling structure 12 extends into the immersion space 11 from the inner surface to form the plate 40. The inner peripheral portion 39 forms a small opening sized to match the shape and size of the radial beam B. The plate 40 may assume the function of isolating the immersion liquid at any end. The supplied immersion liquid flows inward toward the opening, passes through the inner opening, and then flows radially outward toward the recovery opening 25 that surrounds below the plate 40.

[0064] As shown on the right side of FIG. 2b, the fluid handling structure 12 may be composed of two parts (an inner part 12a and an outer part 12b). The inner part 12a and the outer part 12b may move relative to each other mainly in a plane parallel to the opposing surface. The inner part 12a may have a supply opening 34 or an overflow recovery portion 24. The outer part 12b may have a plate 40 and a recovery opening 25. The inner part 12a may have an intermediate recovery portion 42 for recovering the immersion liquid flowing between the inner part 12a and the outer part 12b.

[0065] Thus, the two different versions of the fluid handling structure of FIG. 2b allow the movement of the meniscus 33 in the same direction as the substrate W, enabling an increase in the scan speed and an improvement in the throughput of the lithographic apparatus. However, the movement speed of the meniscus 33 on the surface of the recovery opening 25 in the fluid handling structure 12 on the left side of FIG. 2b may be slow. The fluid handling structure 12 on the right side of FIG. 2b allows for a faster movement of the meniscus 33 by moving the outer portion 12b relative to the inner portion 12a and the final element 100. However, it may be difficult to control the intermediate recovery section 42 to ensure that sufficient immersion liquid is provided therebetween to prevent contact between the inner portion 12a and the outer portion 12b.

[0066] FIG. 2c shows two different versions of the fluid handling structure 12 on the left and right sides that may be used to retain the meniscus 33 of the immersion liquid with respect to the fluid handling structure 12 as described above with respect to FIGS. 2a and / or 2b. Features shown in FIG. 2c that are common to FIGS. 2a and / or 2b share the same reference numerals.

[0067] The fluid handling structure 12 has an inner surface complementary to a frustoconical conical surface. The bottom surface of the fluid handling structure 12 is closer to the opposing surface than the flat bottom surface of the frustoconical shape. The immersion liquid is supplied to the immersion space 11 through an opening formed in the surface of the fluid handling structure 12. The immersion liquid may be supplied through the supply opening 34 on the inner surface of the fluid structure 12. Alternatively or in addition, the immersion liquid may be supplied through the supply opening 20 on the inner surface of the fluid structure 12. Alternatively or in addition, the immersion liquid is supplied through the lower supply opening 23. The immersion liquid may be recovered through a take-out portion (e.g., a recovery opening 21 formed in the inner surface and / or an overflow recovery portion 24 and / or one or more openings on the surface of the fluid handling structure 12 as described later).

[0068] Two different versions of the fluid handling structures 12 on the left and right sides of FIG. 2c hold the meniscus 33. The version of the fluid handling structure 12 on the right side of FIG. 2c may hold the meniscus 33 at a position substantially fixed relative to the final element 100 due to the fixed position of the recovery opening 32a. The version of the fluid handling structure 12 on the left side of FIG. 2c may hold the meniscus 33 below the recovery opening 25, and the meniscus 33 may move along the length and / or width of the recovery opening 25.

[0069] As previously described with respect to FIG. 2b, the inner peripheral portion of the bottom surface of the fluid handling structure 12 may extend into the immersion space 11 from the inner surface to form a plate 40 as shown on the left side. As previously described, this may form a small opening, may isolate the immersion liquid at either end, and / or may flow the immersion liquid inward toward the opening, through the inner opening, and radially outward toward the recovery opening 25 that surrounds below the plate 40. This feature is shown on the left side in FIG. 2c, but may optionally be combined with other shown features. Preferably, as shown on the left side, the immersion liquid is supplied to the immersion space 11 through a supply opening 34 formed in the inner surface of the fluid handling structure 12. The supply opening 34 is disposed on the bottom side of the inner surface (e.g., below the bottom surface of the frustum shape). The supply opening 34 is disposed around the inner surface around and away from the path of the radiation beam B. Alternatively or in addition, the immersion liquid may be supplied through a supply opening 20 in the inner surface of the fluid structure 12. Alternatively or in addition, the immersion liquid is supplied through a lower supply opening 23. Although the supply opening 34 is the preferred liquid supply portion, any combination of the supply opening 34, the supply opening 20, and / or the lower supply opening 23 may be provided.

[0070] As shown on the left side of FIG. 2c, the fluid handling system may include a fluid handling structure 12 as described above and a further device 3000. The fluid handling structure 12 may have a take-out part such as a recovery opening 25 and a liquid supply opening such as a lower supply opening 23. The fluid handling structure 12, in combination with the further device 3000, may be provided with any configuration as disclosed with respect to the left side of FIG. 2a, the right side of FIG. 2a, the left side of FIG. 2b, the right side of FIG. 2b or the right side of FIG. 2c (described later).

[0071] The further device 3000 may be represented as a droplet catcher. The further device 3000 is provided to reduce the remaining liquid on the surface of the substrate W after the fluid handling structure 12 has moved on the surface. The further device 3000 may include a liquid supply part 3010 and at least one take-out part 3020. The at least one take-out part 3020 may be formed in a shape surrounding at least one supply part 3010 in plan view. The at least one liquid supply part 3010 may be configured to provide further liquid to the space 3110 between at least a part of the further device 3000 and the surface of the substrate W. The further device 3000 may be configured to recover at least a part of the liquid through the at least one take-out part 3020. The further device 3000 may be used to combine the liquid remaining on the surface of the substrate W with the liquid in the space 3110, and the further device 3000 is used to take out the liquid so that the amount of liquid remaining on the surface of the substrate W is reduced.

[0072] In FIG. 2c, the further device 3000 is shown as a device separate from the fluid handling structure 12. The further device 3000 may be arranged in the vicinity of the fluid handling structure 12. Alternatively, the further device 3000 may be a part of the fluid handling structure 12 (that is, may be integrally formed with the fluid handling structure 12) (see FIG. 3d. However, any configuration is selectable).

[0073] The additional device 3000 may be configured to provide another liquid to the space 3110 in addition to the liquid provided by the fluid handling structure 12.

[0074] In addition or alternatively, the fluid handling structure 12 may have components as shown on the right side of FIG. 2c. More specifically, the fluid handling structure 12 may include at least one liquid supply portion, two extraction portions (e.g., recovery openings 32a and 32b), and two gas supply portions (e.g., gas supply openings 27a and 27b) formed on the surface of the fluid handling structure 12. The gas supply opening 27a may be omitted, i.e., it is optional. The at least one liquid supply portion may be the same as the lower supply opening 23, the supply opening 20, or the liquid supply opening 34 formed on the inner surface of the fluid handling structure 12 described with respect to the left side of FIG. 2b at the bottom surface of the fluid handling structure 12 described above. The liquid supply portion, the extraction portion, and the gas supply portion may be formed on the surface of the fluid handling structure 12. Specifically, these components may be formed on the surface of the fluid handling structure 12 facing the substrate W, i.e., the bottom surface of the fluid handling structure 12.

[0075] At least one of the two extraction portions may include a porous material 37 inside. The porous material 37 may be provided in an opening (e.g., the recovery opening 32a where the fluid handling structure 12 may extract fluid from the lower fluid handling structure 12 and recover the single-phase flow immersion liquid). The other of the two extraction portions, such as the recovery opening 32b, may recover the immersion fluid as a two-phase extraction portion. The porous material 37 may not be on the same plane as the bottom surface of the fluid handling structure 12.

[0076] Specifically, the fluid handling structure 12 may include a liquid supply section (e.g., a lower supply opening 23). There is a first extraction section (e.g., a recovery opening 32a) radially outside the liquid supply section, a first gas supply section (e.g., a gas supply opening 27a) radially outside the first extraction section, a second extraction section (e.g., a recovery opening 32b) radially outside the first gas supply section, and a second gas supply section (e.g., a gas supply opening 27b) radially outside the second extraction section. Similar to FIG. 2a, additional openings, e.g., those open to the atmosphere, a gas source, or a vacuum, may be present on the bottom surface of the fluid handling structure 12 as described above (with respect to the fluid handling structure 12).

[0077] For example, at least one additional opening (not shown) may be provided on the bottom surface of the fluid handling structure 12. The additional opening is optional. The additional opening may be provided between the first extraction section (e.g., the recovery opening 32a) and the first gas supply section (e.g., the gas supply opening 27a) as described in the above arrangement. Alternatively or in addition, the additional opening may be provided between the second extraction section (e.g., the recovery opening 32b) and the second gas supply section (e.g., the gas supply opening 27b) as described in the above arrangement. The additional opening may be the same as the additional opening 50 described above.

[0078] Optionally, the fluid handling structure 12 includes a recess 29. The recess 29 may be provided between the recovery openings 32a and 32b, or between the gas supply opening 27a and the recovery opening 32b. The shape of the recess 29 may be uniform around the fluid handling structure 12 and may optionally include an inclined surface. When the recess 29 is provided between the recovery openings 32a and 32b, as shown in FIG. 2c, the gas supply opening 27b may be provided on the inclined surface. When the recess 29 is provided between the supply opening 27a and the recovery opening 32b, the gas supply opening 27b may be provided on an inclined surface or on a part of the bottom surface of the fluid handling structure 12 parallel to the surface of the substrate W. Alternatively, the shape of the recess 29 may vary around the fluid handling structure 12. The shape of the recess 29 may vary to change the effect of the gas supplied from the gas supply portion on the fluid below the fluid handling structure 12.

[0079] FIG. 2d shows two different versions of the fluid handling structure 12 in the left and right halves. The fluid handling structure 12 in the left half of FIG. 2d has a liquid injection buffer 41a for holding the buffer amount of the immersion liquid and a liquid injection hole 41 for supplying the immersion liquid from the liquid injection buffer to the space 11. An inner liquid recovery opening 43 for guiding the liquid to an inner recovery buffer 43a provided with a porous member is provided outside the liquid injection hole 41. A recess 29 similar to that described with respect to FIG. 2c is provided outside the inner liquid recovery opening 43. A gas guide groove 44 with an outer recovery hole 44a open on the outer side of the recess 29 on the lower surface of the fluid handling structure 12 is provided. The outer recovery hole 44a guides the two-phase recovery flow to an outer recovery buffer 44b provided with a porous member. On the outermost side, a gas sealing hole 45 is provided to connect between the gas sealing buffer volume 45a and the space under the fluid handling structure 12 and to provide a gas flow for inclusion in the immersion liquid.

[0080] The fluid handling structure 12 in the right half of FIG. 2d has a liquid supply opening 20 in its inner inclined surface. Below the fluid handling structure 12, a take-out opening 25 provided with a porous member 37 (from the inside to the outside), a first gas knife opening 26a, a second gas knife opening 26b, and a third gas knife opening 26c are provided. Each of these openings opens into a groove below the fluid handling structure 12 that provides a buffer capacity. The outermost portion of the fluid handling structure 12 is stepped so as to provide a larger gap between the fluid handling structure 12 and the substrate W.

[0081] Figs. 2a-2d show examples of different configurations that can be used as part of a fluid handling system. Although the examples provided above refer to specific take-out and recovery parts, it is understood that it is not necessary to use exactly the same type of take-out and / or recovery parts. In some cases, different terms may be used to indicate the position of the members, but the same functional features may be provided. The examples of the take-out parts mentioned above include a recovery opening 21, an overflow recovery part 24, a recovery opening 25 (preferably provided with a porous plate and / or a chamber 35), a gas recovery opening 28, a pinning opening 32, a recovery opening 32a, a recovery opening 32b, and / or an intermediate recovery part 42. The examples of the supply parts mentioned above include a supply opening 20, a lower supply opening 23, a gas knife opening 26, a gas supply opening 27a, a gas supply opening 27b, and / or a supply opening 34. Generally, the take-out parts used to take out / recover fluid, liquid or gas are each interchangeable with at least any one of other usage examples for taking out / recovering fluid, liquid or gas. Similarly, the supply parts used to supply fluid, liquid or gas are each interchangeable with at least any one of other usage examples for supplying fluid, liquid or gas. The take-out part may take out / recover fluid, liquid or gas from the space by being connected to a negative pressure that draws the fluid, liquid or gas into the take-out part. The supply part may supply fluid, liquid or gas to the space by being connected to the corresponding supply part.

[0082] As described above, the use of an immersion fluid / liquid is useful in enhancing the resolution of smaller features on a substrate, but there are issues regarding the use of the immersion fluid / liquid with respect to defects introduced onto the substrate.

[0083] Generally, when an immersion liquid is used, droplets of the immersion liquid can be left on the surface of the substrate W. The meniscus 33 at the edge of the immersion liquid can collide with the droplet on the surface of the substrate W. When the droplet hits the meniscus 33, gas can be trapped within the immersion liquid. This results in bubbles in the immersion liquid. The formation of bubbles in the immersion liquid can lead to defects on the substrate W. The droplets remaining on the surface of the substrate W can result in dry spots and / or can affect the chemical properties of the resist, leading to defects.

[0084] The droplet generation rate is known to increase with the moving speed of the substrate W with respect to the fluid handling system. In some cases, below a critical scan speed, droplet formation is absent / negligible, and above the critical scan speed, non-negligible droplet formation occurs. The critical scan speed is related to the static receding contact angle between the immersion liquid and the resist provided on the substrate W. As the static receding contact angle increases, the critical scan speed also increases. Since the critical scan speed can be a limiting factor for the throughput of the lithography apparatus, it is desirable to increase the critical scan speed. Efforts to increase the critical scan speed include increasing the static receding contact angle by changing the composition of the resist or by providing a top coat on the resist.

[0085] Techniques for increasing the critical scan speed are disclosed in the document referred to herein as RD681087. RD681087 is hereby incorporated by reference in its entirety. RD681087 is a publication by QUESTEL RESEARCH DISCLOSURE. RD681087 is a document titled "A FLUID HANDLING SYSTEM, METHOD AND LITHGRAPHIC APPARATUS", with a database number of 681087 and a digital publication date of December 21, 2020. The link to RD681087 is "https: / / www.researchdisclosure.com / database / RD681087" (searched on June 26, 2022).

[0086] RD681087 discloses increasing the maximum allowable speed of relative movement between a fluid handling system and a substrate without generating substantial droplet formation by providing a fluid handling system in which a meniscus of a fluid moves in response to relative movement between the substrate and the fluid handling system. Some of the techniques disclosed in RD681087 are described below with reference to FIGS. 3a and 3b.

[0087] FIGS. 3a and 3b show a part of the fluid handling system 301. The fluid handling system 301 may confine the immersion liquid in the liquid confinement space between a part of the projection system PS and the surface of the substrate W. The immersion liquid may be any of the immersion fluids described above. For example, the immersion liquid may be water. The radiation beam B projected from the projection system PS may irradiate the surface of the substrate W through the immersion liquid.

[0088] FIG. 3a shows only a part of a fluid handling system 301 that supports a meniscus 310 of an immersion liquid. The meniscus 310 forms a boundary between the immersion liquid and the ambient environment of the fluid handling system 301. Although not shown in FIG. 3a, the main part of the fluid handling system 301 is arranged in the direction indicated by arrow 306. The main part of the fluid handling system 301 may include the immersion liquid and may include any part of any of the various structures or any other system that localizes the immersion liquid below the projection system PS as disclosed above with reference to FIGS. 2a to 2d. In particular, the main part of the fluid handling system 301 may include an immersion space such as immersion space 11 as described with reference to FIGS. 2a to 2d.

[0089] As shown in FIG. 3a, the fluid handling system 301 is provided above a substrate W. The substrate W may include a wafer 305 and a resist coating 304 on the wafer 305. There is a channel 308 between the fluid handling system 301 and the substrate W. A part of the channel 308 between the main part of the fluid handling system 301 arranged in the direction 306 and the meniscus 310 may include the immersion liquid. A part of the channel 308 between the meniscus 310 and the external environment of the fluid handling system 301 arranged in the direction 307 may include a gas.

[0090] The fluid handling system 301 includes a first extraction part 302. The first extraction part 302 includes a first extraction conduit 302b. The first extraction conduit 302b is a conduit for fluid and may provide a flow of the immersion liquid exiting from the fluid handling system 301. The first extraction part 302 also includes a first extraction opening 302a provided on the upper surface of the channel 308. The first extraction opening 302a is the end of the first extraction conduit 302b.

[0091] The fluid handling system 301 includes a second extraction unit 303. The second extraction unit 303 includes a second extraction conduit 303b. The second extraction conduit 303b is a conduit for fluids such as gas. The second extraction unit 303 also includes a second extraction opening 303a provided on the upper surface of the channel 308. The second extraction opening 303a is the end of the second extraction conduit 303b.

[0092] Between the first extraction unit 302 and the second extraction unit 303, there is an upper surface of the channel 308 represented as a damper 311. The length of the damper 311 determines the interval between the first extraction unit 302 and the second extraction unit 303 along the length of the channel 308.

[0093] The first extraction unit 302 may be configured to extract the immersion liquid by the fluid flow 309. Only the fluid flow through the first extraction unit 302 may be substantially the fluid flow 309 of the immersion liquid. However, the first extraction unit 302 may extract gas from the external environment of the fluid handling system 301. Thus, the fluid flow through the first extraction unit 302 may be a two-phase flow. When there is a fluid flow through the first extraction unit 302, there may simultaneously be a gas flow 314 through the second extraction unit 303.

[0094] The second extraction unit 303 may be configured to extract gas from the channel 308. FIG. 3b shows the gas flow 314 for gas extraction. The gas flow 314 may generate a negative pressure in the channel 308.

[0095] Although not shown in FIGS. 3a and 3b, the main part of the fluid handling system 301 arranged in the direction 306 may comprise a fluid handling structure having an inner surface configured to limit the immersion liquid. The first extraction part 302 and the second extraction part 303 are arranged radially away from the main part of the fluid handling system 301. The second extraction part 303 may be arranged further away from the inner surface of the fluid handling structure than the first extraction part 302. Alternatively, the first extraction part 302 and the second extraction part 303 may be part of the main part of the fluid handling system 301. The second extraction part 303 may be arranged further away from the center of the fluid handling system 301 than the first extraction part 302.

[0096] The first operating state of the fluid handling system 301 is shown in FIG. 3a. In the first operating state, there is no relative movement between the substrate W and the fluid handling system 301. The first extraction part 302 may be configured such that, in the first operating state, the amount of immersion liquid extracted therethrough does not substantially exceed the amount required to maintain the meniscus 310 at substantially the same position along the channel 308. The fluid flow rate through the first extraction part 302 is the minimum flow rate that can substantially hold the meniscus 310 in a stationary state when there is no relative movement between the substrate W and the fluid handling system 301.

[0097] The second operating state of the fluid handling system is shown in FIG. 3b. In the second operating state, the substrate W may move relative to the fluid handling system 301. The second operating state includes a scan movement in the scan direction. The scan direction may be substantially perpendicular to the propagation direction of the radiation beam B. The scan direction may be the direction 312 as shown in FIG. 3b. Note that the second operating state may include relative movement other than the scan movement between the substrate W and the fluid handling system 301. For example, the second operating state may include a preparatory movement before the scan movement.

[0098] The first extraction section 302 may be configured such that the amount of immersion liquid extracted therethrough is substantially the same in both the first and second operating states. The movement of the substrate W in the direction 312 generates a shearing force on the immersion liquid in the channel 308. For this reason, the meniscus 310 moves along the channel 308 in the direction 313. The increase in the flow of the immersion liquid into the channel 308 may be referred to as a quet flow, or may be referred to as a shear-driven flow or a pressure-driven flow. The generation of a negative pressure in the channel 308 by the gas flow 314 also supports the movement of the meniscus 310 along the channel 308.

[0099] In the second operating state, the meniscus 310 is not held stationary by the fluid flow through the first extraction section 302. The fluid flow through the first extraction section 302 is sufficient to maintain the meniscus 310 in a stationary state only when there is no relative movement between the fluid handling system 301 and the substrate W. Accordingly, in the second operating state, the meniscus 310 moves along the channel 308.

[0100] Advantageously, the maximum allowable speed of the relative movement between the fluid handling system 301 and the substrate W is increased. The relative movement speed between the meniscus 310 and the substrate W is below the critical scan speed so that significant droplet formation does not occur. The relative movement speed between the fluid handling system 301 and the meniscus 310 increases the relative movement speed between the fluid handling system 301 and the substrate W. The relative movement speed between the fluid handling system 301 and the substrate W can increase up to twice that of the critical scan speed of a known system in which the meniscus 310 in the channel 308 is substantially stationary.

[0101] The damper 311 may be configured such that its surface characteristics support proper movement of the end of the meniscus 310. In particular, the surface of the damper 311 may be coated or may be configured to be either hydrophobic, hydrophilic or porous.

[0102] The surface of the damper 311 may be configured to be substantially parallel to the surface of the substrate W.

[0103] Alternatively, the surface of the damper 311 may be curved or inclined away from the surface of the substrate W. The first end of the surface of the damper 311 is at the first extraction portion 302, and the second end of the surface of the damper 311 is at the second extraction portion 303. The surface of the damper 311 may be configured such that the distance between the surface of the damper 311 and the surface of the substrate W is greater at the second end than at the first end.

[0104] The damper 311 described above may be referred to as the first damper 311. As shown at least in FIGS. 3a and 3b, the fluid handling system 301 may include a second damper 315. The surface of the second damper 315 is a length portion of the upper surface of the channel 308 on the other side of the first extraction portion 302 with respect to the first damper 311. The second damper 315 may be configured such that the immersion liquid is supported between the surface of the second damper 315 and the surface of the substrate W.

[0105] The surface of the second damper 315 may be parallel to the surface of the substrate W. The distance between the surface of the second damper 315 and the surface of the substrate W may be the same as the distance between all or at least a part of the surface of the first damper 311 and the surface of the substrate W. Alternatively or additionally, the distance between all or at least a part of the surface of the first damper 311 and the surface of the substrate W may be greater than the distance between at least a part of the surface of the second damper 315 and the surface of the substrate W.

[0106] Starting from the second extraction section 303 and extending in direction 307 towards the external environment of the fluid handling system 301, the upper surface 316 of the channel 308 may be parallel to the surface of the substrate W. Alternatively, the upper surface 316 of the channel 308 may be inclined / curved such that the distance between the upper surface 316 of the channel 308 and the surface of the substrate W varies. The pressure of the gas within the channel 308 may depend on the shape of the upper surface 316. The shape of the surface 316 may be determined to generate an appropriate pressure of the gas within the channel 308 in order to support the movement of the meniscus 310 under the desired operating conditions.

[0107] The technology described above has been confirmed to be effective typically only during the exposure process involving relatively small serpentine movements. However, problems arise when high-speed movement over a long distance is required. The long movement may include the movement necessary to avoid the sensor and the movement while the substrate support changes. The long movement may extend over a distance of about 30 cm. When high-speed movement is executed over a long distance, the distance that the meniscus 310 moves along the channel 308 increases. For this reason, the required minimum length of the surface of the damper 311 between the first extraction section 302 and the second extraction section 303 increases. Only during the exposure process, the required minimum length of the damper 311 may be between about 2 cm and 5 cm. However, in order to enable long high-speed movement, the required minimum length of the damper 311 may increase to between about 10 cm and 20 cm. Such an increase in the damper length substantially increases the footprint of the fluid handling system 301 and also increases the risk of water loss outside the wet area on the substrate W.

[0108] Embodiments solve the aforementioned problems by providing a meniscus control surface that allows two different operating states. In the first operating state, the meniscus is held stationary within the channel 308, i.e., liquid is withdrawn through the meniscus control surface such that the meniscus 310 is fixed to the meniscus control surface. In the second operating state, as described above with reference to FIGS. 3a and 3b, liquid withdrawal through the meniscus control surface may be substantially absent such that the meniscus 310 can move along the channel 308.

[0109] When high-speed movement over a long distance is required, the first operating state is used so that a long damper is not required. In the first operating state, the speed of relative movement between the substrate W and the fluid handling system 301 may be limited to be lower than the speed at which substantial droplet formation occurs on the substrate W. When high-speed movement over a short distance is required, the second operating state is used. In the second operating state, the speed of relative movement between the substrate W and the fluid handling system 301 may be faster than that in the first operating state for the movement of the meniscus 310. The embodiments are described in more detail below with reference to FIGS. 4 and 5.

[0110] FIG. 4 schematically shows a part of the fluid handling system 301 according to the first embodiment. In the first embodiment, a part of the fluid handling system 301 may be different from that described above with reference to FIGS. 3a and 3b by further including a meniscus control surface 401. The meniscus control surface 401 is constituted by the upper surface of the channel 308, that is, on the opposite side of the channel 308 from the substrate W.

[0111] The meniscus control surface 401 may be adjacent to the damper 311 and disposed between the first extraction portion 302 and the second extraction portion 303. The meniscus control surface 401 is preferably disposed near the first extraction portion 302.

[0112] Note that FIG. 4 schematically shows the meniscus control surface 401 and is not to actual scale. The meniscus control surface 401 is preferably significantly shorter than the damper 311. For example, the length of the meniscus control surface 401 may be between about 1 mm and 10 mm, preferably less than 5 mm. The length of the damper 311 may be between about 20 mm and 50 mm and may be longer.

[0113] The meniscus control surface 401 may be formed of any of a number of materials known in the art. For example, the meniscus control surface 401 may be formed of metal or plastic. Preferably, the meniscus control surface 401 is coated such that its surface properties depend on the coating. In particular, a coating that makes the meniscus control surface 401 hydrophilic may be applied. Preferably, the surface of the damper 311 is configured to be hydrophobic. Such surface properties of the meniscus control surface 401 and the damper 311 support different first and second operating states, as described in detail below.

[0114] The meniscus control surface 401 may be the surface of a micro sieve. The micro sieve comprises small apertures arranged such that a fluid, such as an immersion liquid, can flow through them. On the side of the micro sieve opposite to the channel 308, there may be a bypass flow path. The bypass flow path may be arranged to provide a liquid flow along the side of the substrate W opposite to the meniscus control surface 401. The bypass flow path may comprise a liquid inlet 402 configured to supply a liquid flow 403 to the bypass flow path. The bypass flow path may comprise a liquid outlet 405 configured to provide a liquid flow 404 out of the bypass flow path.

[0115] The bypass flow path may be arranged to wet the apertures of the micro sieve. That is, the liquid flow along the bypass flow path may ensure that substantially all of the apertures of the micro sieve are covered by liquid, even when there is substantially no liquid flow through the apertures. Thus, in all operating states of the fluid handling system 301, the micro sieve may have a wet surface. The micro sieve is preferably configured such that the liquid in its apertures has a high capillary pressure.

[0116] Although not shown in FIG. 4, the first embodiment may include a flow control system configured to control the flow rate of the liquid through the liquid outlet 405. The flow control system may include, for example, a variable displacement pump, a multi-way valve system that may apply different flow restrictions, or any other technique for controlling the liquid flow rate through the liquid outlet 405.

[0117] The liquid received by the liquid inlet 402 may be branched from the same liquid supply as that for the main part of the fluid handling system 301. Alternatively, a separate liquid supply may be provided for the bypass flow path.

[0118] The flow control system may be configured to control at least a part of the fluid handling system 301 according to the first embodiment to be in at least one of the first operating state and the second operating state.

[0119] In the first operating state, the flow control system may be configured to apply a negative pressure on the micro sieve. The flow control system may be configured such that the flow rate of the liquid flow 404 exiting the liquid outlet 405 is greater than the flow rate of the supply liquid flow 403 through the liquid inlet 402. The flow of the immersion liquid through the openings of the micro sieve provides additional liquid in the liquid flow 404 exiting the bypass flow path. The effect of the liquid flow through the micro sieve is that the meniscus 310 is fixed to the surface of the micro sieve. That is, the meniscus 310 of the immersion liquid is held substantially stationary between the surface of the micro sieve and the surface of the substrate W. The flow control system is preferably configured such that, in the first operating state, the negative pressure applied on the micro sieve is less than the capillary pressure of the openings of the micro sieve. This ensures that all of the openings of the micro sieve remain wet in the first operating state.

[0120] The micro sieve is preferably disposed near the first extraction portion 302 in order to reduce the entire wet area in the first operating state.

[0121] In the second operating state, the flow control system may be configured to apply a fluid negative pressure that is less than, and preferably substantially less than, the capillary pressure of the opening to the opening of the microsieve. The pressure difference across the microsieve is preferably minimized and may be substantially zero. The flow rate of the liquid through the liquid outlet 405 may be substantially the same as the flow rate of the liquid through the liquid inlet 402. There may be substantially no flow of the immersion liquid or gas through the opening of the microsieve. If there is a small liquid flow covering the liquid in the channel 308 through the opening of the microsieve from the channel 308, this may be compensated by reducing the liquid extraction through the first extraction portion 302.

[0122] In the second operating state, the meniscus 310 can move freely with respect to the surface of the microsieve and the surface of the damper 311. Thus, the fluid handling system 301 may be operated with a movable meniscus, substantially as described in RD681087.

[0123] In the second operating state, the flow control system may alternatively be configured to apply a slight positive pressure on the microsieve such that there is a small liquid flow into the channel 308 through the microsieve from the bypass flow path. This may increase the acceptable movement speed of the substrate W with respect to the fluid handling system 301 in the second operating state.

[0124] In the first operating state, the flow rate of the liquid flow 404 exiting the bypass flow path may be the first fluid flow rate. In the second operating state, the flow rate of the liquid flow 404 exiting the bypass flow path may be the second fluid flow rate. The first fluid flow rate may be greater than the second fluid flow rate.

[0125] In the first embodiment, a part of the fluid handling system 301 shown in FIG. 4 may be substantially the same as a part of the fluid handling system 301 shown in FIGS. 3a and 3b and as described in RD681087.

[0126] Advantageously, the provision of the meniscus control surface 401 enables the meniscus 310 to be properly controlled when long movement is required. The advantage of the wet meniscus control surface 401 in all operating states is that there is substantially only liquid flow through the meniscus control surface 401 in all operating states. Such a single-phase flow does not exert a large force on the substrate W. Different operating states can be switched quickly.

[0127] If pinning of the meniscus 310 is instead performed at the first extraction portion 302, it is not possible to avoid the flow of both liquid and gas through the first extraction portion 302. This two-phase flow increases the required extraction force through the first extraction portion 302 and exerts a large force on the substrate W. Furthermore, the time required to switch from the second operating state to the first operating state may be substantially slower than the switching time when the technique according to the embodiment is used and may exceed 100 ms.

[0128] FIG. 5 schematically shows a part of the fluid handling system 301 according to the second embodiment. The second embodiment may be different from the techniques disclosed in the first embodiment and RD681087 in that there is no first extraction portion 302. In the second embodiment, the meniscus control surface 401 additionally provides fluid extraction that was performed by the first extraction portion 302 in the techniques disclosed in the first embodiment and RD681087.

[0129] In the second embodiment, the fluid flow through the micro sieve may be increased by substantially the same amount as the fluid flow through the first extraction portion 302 in the first embodiment. The fluid extraction through the liquid outlet 405, i.e., the liquid flow 404 exiting from the bypass flow path, may likewise be increased due to the increased fluid flow through the micro sieve.

[0130] In the first and second operating states, the fluid flow rate may be appropriately changed in view of the absence of the first extraction portion 302. Otherwise, the operation of the second embodiment may be the same as that of the first embodiment.

[0131] Advantageously, in the second embodiment, the first extraction unit 302 is absent. This reduces the footprint of the extraction unit and also reduces costs.

[0132] As described above, the generation of droplets and / or bubbles increases with the speed of movement of the substrate W relative to the fluid handling system. Below the critical scan speed, there is no (or negligible) formation of droplets and / or bubbles, and above the critical scan speed, there may be significant formation of droplets and / or bubbles. The critical scan speed relates to the static receding contact angle between the immersion liquid and the resist provided on the substrate W. Therefore, the critical scan speed may be increased through appropriate control of the contact angle.

[0133] According to the third embodiment, a new technique is provided for increasing the maximum allowable speed of relative movement between the fluid handling system and the substrate W. The electro-wetting effect is used to change the contact angle and increase the critical scan speed. The electro-wetting effect may also be used, in addition or alternatively, to increase the critical scan speed by changing the contact line of the immersion fluid. The contact line is the boundary line of the meniscus of the immersion fluid on the substrate facing the surface of the fluid handling structure.

[0134] Figures 6a and 6b schematically show a part of the fluid handling system 601 according to the third embodiment. The fluid handling system 601 includes an electro-wetting structure 605. At least a part of the substrate facing the surface of the fluid handling system 601 is provided by the substrate facing the surface of the electro-wetting structure 605. There is a meniscus 602 of the immersion fluid between the substrate facing the surface of the electro-wetting structure 605 and the substrate W.

[0135] As shown in FIG. 6a, when the fluid handling system 601 is in a stationary state and the substrate W moves in direction 603, the meniscus 602 may move in direction 604 along the substrate facing the surface of the electro-wetting structure 605. Similarly, as shown in FIG. 6b, when the fluid handling system 601 is in a stationary state and the substrate W moves in direction 606, the meniscus 602 may move in direction 607 along the substrate facing the surface of the electro-wetting structure 605. The movement of the meniscus 602 along the surface of the electro-wetting structure 605 is similar to the movement of the meniscus 310 along the surface of the damper 311 in the first and second embodiments described above. Therefore, the movement of the meniscus 602 increases the maximum allowable speed of the relative movement between the fluid handling system 601 and the substrate W.

[0136] The electro-wetting structure 605 is configured to use the electro-wetting effect to change the contact angle and / or contact line of the meniscus 602. The electro-wetting effect is a known technique in which an electric field is used to change the surface properties of a fluid (see (searched on [date])). https: / / en.wikipedia.org / wiki / Electroウェッティング」(May 25, 2023 for reference).

[0137] The electro-wetting structure 605 comprises one or more embedded electrodes. Each electrode may be covered by an electrical insulator (not shown), at least on the side facing the substrate. The electrical insulator may be a dielectric. The substrate facing the surface of the electrical insulator may be coated to be hydrophobic. The substrate facing the surface of the electrical insulator may be a surface along which the meniscus 602 is movable. A voltage with respect to the ground potential may be applied to each electrode such that an electric field is generated. The ground potential may be provided within the fluid handling system 601, the substrate support WT, the substrate W or another part of the lithographic apparatus. The electric field depending on the applied voltage may change the properties of the substrate facing the surface of the electro-wetting structure 605 due to the electro-wetting effect. Thus, the contact angle and / or the contact line of the meniscus 602 may be changed according to the applied voltage.

[0138] Contact angle θ EW depends on the voltage applied to the electrode according to the following equation.

Equation

[0139] The electro-wetting structure 605 may be used to change the contact angle to reduce the contact line movement speed at the substrate end of the meniscus 602.

[0140] As shown in FIG. 6a, the fluid handling system 601 may be in a stationary state, and the substrate W may move in the direction 603. By applying a voltage to one or more electrodes in the electro-wetting structure 605, the contact angle at the fluid handling system end of the meniscus 602 is reduced. This also moves the contact line in the direction 604 and partially reduces the movement of the contact line at the substrate end of the meniscus 602. This allows for a faster relative movement of the fluid handling system 601 and the substrate W.

[0141] As shown in FIG. 6b, the fluid handling system 601 may be in a stationary state, and the substrate W may move in the direction 606. Instead, the electro-wetting structure 605 may be operated such that a zero voltage or a voltage of reduced magnitude is applied to its one or more electrodes. The hydrophobicity of the substrate facing the surface of the electro-wetting structure 605 may increase the movement of the contact line in the direction 607. This also partially reduces the movement of the contact line at the substrate end of the meniscus 602. This has the effect of changing the contact angle and allowing for a faster relative movement of the fluid handling system 601 and the substrate W.

[0142] In the third embodiment, one or more electrodes of the electro-wetting structure 605 are controllable to change the contact angle and / or the contact line of the meniscus 602 of the immersion fluid. For this reason, the third embodiment allows for a faster relative movement of the fluid handling system 601 and the substrate W without a substantial increase in the formation of droplets and / or bubbles.

[0143] The implementation of the third embodiment includes the electro-wetting structure 605 used in combination with the techniques of the first and second embodiments described above. In particular, a damper 311 as described above with reference to FIGS. 3a to 5 may include the electro-wetting structure 605. The movement of the meniscus 310 along at least a portion of the surface of the damper 311 may depend on the control of the electro-wetting structure 605.

[0144] According to the fourth embodiment, the electro-wetting structure 605 includes a plurality of electrodes arranged in an array (not shown). The electrodes may be controlled independently of each other. The characteristics of different regions of the substrate facing the surface of the electro-wetting structure 605 may be changed by the operation of the electrodes. This may enable advantageous control of the contact line and / or contact angle of the immersion fluid, and the movement of any droplet of the immersion fluid on the surface of the electro-wetting structure 605.

[0145] In the first implementation of the fourth embodiment, the electro-wetting structure 605 may be used to pre-wet at least a part of the surface of the electro-wetting structure 605. In known techniques, the movement of the meniscus 602 in response to the movement of the substrate W wets a part of the surface of the fluid handling system 601. The pre-wetting technique of the fourth embodiment moves the immersion fluid onto at least a part of the surface of the fluid handling system 601 before the wetting caused by the movement of the substrate W. The pre-wetted surface is at least a part of the substrate facing the surface of the electro-wetting structure 605. The pre-wetted surface may be represented as a precursor film of the immersion fluid.

[0146] The electrodes in the electro-wetting structure 605 may be controlled such that at least a part of their surface is pre-wetted by a part of the immersion fluid. The effect of pre-wetting is that the contact line has already advanced before the wetting caused by the movement of the substrate W. Therefore, the contact line moves a smaller distance in response to the movement of the substrate W.

[0147] Pre-wetting may be performed for all movements of the substrate W. In particular, pre-wetting may be performed for both the scanning movement and the positioning movement between the scanning movements.

[0148] In a second implementation of the fourth embodiment, the electrodes of the electro-wetting structure 605 may be operated to slow the movement of the meniscus 602 when it passes over the edge of the substrate W.

[0149] In a third implementation of the fourth embodiment, the electro-wetting structure 605 may be used to move any droplets of the immersion fluid on the surface of the electro-wetting structure 605. The droplets may be moved to positions where they may be removed.

[0150] In a fourth implementation of the fourth embodiment, the electro-wetting structure 605 may be used in combination with the techniques of the first and second embodiments described above. In particular, a damper 311 as described above with reference to FIGS. 3a through 5 may include the electro-wetting structure 605. The movement of the meniscus 310 along at least a portion of the surface of the damper 311 may depend on the control of the electro-wetting structure 605.

[0151] Embodiments include many variations and modifications to the techniques described above.

[0152] In the third and fourth embodiments described above, the exemplary implementations shown in FIGS. 6a and 6b include a conduit filled with liquid adjacent the inner end of the electro-wetting structure 605. This liquid-filled conduit is optional and may not be present in all implementations of the third and fourth embodiments.

[0153] In the first and second embodiments described above, the meniscus control surface 401 is a micro-sieve. Embodiments also include a meniscus control surface 401 that is any other type of surface through which liquid may flow. For example, the meniscus control surface 401 may be a porous member or may include micro-slits or capillaries.

[0154] In the foregoing embodiments, the first extraction unit 302 and the second extraction unit 303 have been described. The embodiments include those having a plurality of such first extraction units 302 and / or a plurality of such second extraction units 303. The plurality of first extraction units 302 may be provided around the center of the fluid handling system 301. The plurality of first extraction units 302 may be provided in any configuration. For example, they may be in a circular, square, rectangular or star-shaped configuration. The first extraction opening 302a of each first extraction unit 302 may have any shape. For example, each first extraction opening 302a may be circular, square, rectangular or slot-shaped. The plurality of second extraction units 303 may be provided around the center of the fluid handling system 301. For example, they may be in a circular, square, rectangular or star-shaped configuration. The configuration of the second extraction unit 303 may be the same as or different from the configuration of the first extraction unit 302.

[0155] The determination of whether to use the first or second operating state, and the determination of the relative movement speed between the fluid handling system 301 and the substrate W in each operating state may depend on many different situations. These may include the length of the required movement, the type of process being performed, and the surface characteristics of the substrate W or the substrate support. For example, the use of the first operating state and the movement speed in the first operating state may depend on the hydrophobic strength of the surface of the substrate W.

[0156] In the foregoing embodiments, the bypass flow path comprises a flow substantially of only liquid. The embodiments also include a bypass flow path that provides a fluid flow with a fluid that is a bubble flow. That is, the fluid flow in the bypass flow path may comprise both a liquid flow and a gas flow.

[0157] In the first operating state, the embodiments include a flow control system configured such that, in addition to the flow of the immersion liquid through the openings of the micro sieves, there is also a small gas flow through the micro sieves. This may allow a greater force to be applied to hold the meniscus 310 stationary with respect to the surface of the micro sieves.

[0158] The addition of the meniscus control surface 401 according to the embodiment may be applied to the technology disclosed in RD681087 and all other types of fluid handling systems.

[0159] In the above-described embodiment, the surfaces of the meniscus control surface 401 and the damper 311 were described as being on the upper surface of the channel 308. In a typical configuration of the horizontally provided substrate W, the surface is the upper surface of the channel 308. However, the embodiment more generally includes the surfaces of the meniscus control surface 401 and the damper 311 provided on the surface of the fluid handling system 301 substantially parallel to the surface of the substrate W. The surface of the substrate W is not limited to being horizontally provided.

[0160] The present invention may provide a lithographic apparatus. The lithographic apparatus may have some or all of the other features or components of the lithographic apparatus as described above. For example, the lithographic apparatus may optionally include at least one or more of a source SO, an illumination system IL, a projection system PS, a substrate support WT, etc.

[0161] Specifically, the lithographic apparatus may include a projection system PS configured to project a radiation beam B onto an area of the surface of the substrate W. The lithographic apparatus may further include the fluid handling system 301 described in any of the above embodiments and variations.

[0162] The lithographic apparatus may include an actuator configured to drive the substrate W with respect to the fluid handling system 301. In this way, the actuator may be used to control the position of the substrate W (or the position of the fluid handling system 301). The actuator may be a substrate support (e.g., a substrate table) WT and / or a second positioner PW configured to accurately position a substrate holder and / or the substrate support WT configured to hold the substrate W, or may include them.

[0163] In this text, although specific references may have been made to the use of lithographic apparatus in the manufacture of ICs, it should be understood that the lithographic apparatus described herein may have other uses. Possible other uses include the manufacture of integrated optical systems, guidance and detection patterns for magnetic domain memories, flat panel displays, liquid crystal displays (LCDs), thin film magnetic heads, and the like.

[0164] As far as the context allows, embodiments of the invention may be implemented in hardware, firmware, software, or any combination thereof. Embodiments of the invention may be implemented by instructions stored on a machine-readable medium that may be read and executed by one or more processors. The 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, the machine-readable medium may include read-only memory (ROM), random access memory (RAM), magnetic storage media, optical storage media, flash memory devices, electrical, optical, acoustic, or other forms of transmission signals (e.g., carrier waves, infrared signals, digital signals, etc.), and others. Further, firmware, software, routines, instructions may be described as performing certain actions. However, such descriptions are merely for convenience, and such actions are actually brought about by a computing device, a processor, a controller, or other devices that execute firmware, software, routines, instructions, etc., and may interact with the physical world through an actuator or other devices.

[0165] Although specific references may have been made in this text to embodiments of the invention in the context of a lithographic apparatus, the embodiments may be used in other apparatus. The embodiments may form part of an apparatus for measuring or processing an object such as a wafer (or other substrate) or a mask (or other patterning device), for example a mask inspection apparatus, a metrology apparatus, or any apparatus. These apparatus may generally be referred to as lithographic tools. Such lithographic tools may use atmospheric (non-vacuum) conditions.

[0166] Although specific references may have been made above to the use of embodiments of the invention in the context of optical lithography, the invention is understood not to be limited to optical lithography as far as the context allows.

[0167] Embodiments include the following numbered items. Item 1: A fluid handling system for a lithographic apparatus, configured to confine immersion fluid in a liquid confinement space between a part of the projection system in the lithographic apparatus and the surface of a substrate such that a radiation beam projected from the projection system can irradiate the surface of the substrate by passing through the immersion fluid, comprising a meniscus control surface for controlling movement of the meniscus of the immersion fluid, wherein in a first operating state, the meniscus control surface is configured to hold the meniscus of the immersion fluid substantially stationary between the meniscus control surface and the surface of the substrate, and in a second operating state, the meniscus control surface is configured to allow movement of the meniscus of the immersion fluid. Fluid handling system. Item 2: Further comprising a damper, wherein in the second operating state, the damper is configured to support movement of the meniscus of the immersion fluid between the surface of the damper and the surface of the substrate. The system according to item 1. Item 3: The meniscus control surface comprises the surface of a micro sieve or a porous member, the system according to item 1 or 2. Item 4: The meniscus control surface comprises a wet surface, the system according to any one of items 1 to 3. Item 5: The system according to any one of items 1 to 4, further comprising a bypass flow path configured to provide a fluid flow along the opposite side of the meniscus control surface with respect to the substrate. Item 6: A fluid inlet configured to supply a fluid flow to the bypass flow path, and A fluid outlet configured to provide the fluid flow outside the bypass flow path, and The system according to item 5, further comprising the same. Item 7: The system according to item 6, further comprising a flow control system configured to control the flow rate of the fluid through the fluid outlet. Item 8: The flow control system is configured to control the flow rate of the fluid through the fluid outlet to a first fluid flow rate or a second fluid flow rate, The first fluid flow rate is greater than the second fluid flow rate, The first fluid flow rate is for providing the first operating state, The second fluid flow rate is for providing the second operating state, The system according to item 7. Item 9: The fluid flow in the bypass flow path is a liquid flow, the system according to any one of items 5 to 8. Item 10: The meniscus control surface is hydrophilic, the system according to any one of items 1 to 9. Item 11: The damper surface is hydrophobic, and / or, The damper is provided with an electro-wetting structure, The electro-wetting structure includes one or more electrodes arranged to apply an electro-wetting effect to at least a part of a substrate facing the surface of the fluid handling system. The one or more electrodes of the electro-wetting structure are controllable to change the contact angle and / or contact line of the meniscus of the immersion fluid. The system according to any one of items 1 to 10. Item 12: It includes a fluid handling structure having an inner surface configured to limit the immersion fluid. It further includes a take-out portion configured to take out the immersion fluid. The meniscus control surface and the take-out portion are arranged radially away from the inner surface of the fluid handling structure. The take-out portion is arranged further away from the inner surface of the fluid handling structure than the meniscus control surface. The system according to any one of items 1 to 11. Item 13: The take-out portion is configured such that substantially only gas flows through it during use, for the system according to item 12. Item 14: The system according to item 12 or 13, comprising a plurality of take-out portions. Item 15: Each of the take-out portions is a first take-out portion. It further includes a second take-out portion configured to take out the immersion fluid. The second take-out portion is arranged radially away from the inner surface of the fluid handling structure. The second take-out portion is arranged closer to the inner surface of the fluid handling structure than the meniscus control surface. The meniscus control surface is arranged between the first and second take-out portions. The system according to any one of items 12 to 14. Item 16: The system according to item 15, comprising a plurality of second take-out portions. Item 17: The system according to item 15 or 16, wherein each second extraction part is configured such that only substantially liquid flows therethrough during use. Item 18: The system according to any one of items 1 to 17, wherein in the second operating state, the meniscus control surface is configured such that during use, the meniscus moves relative to the meniscus control surface in response to movement of the substrate relative to the fluid handling system. Item 19: A fluid handling system for a lithographic apparatus, configured to confine the immersion fluid in a liquid confinement space between a part of the projection system in the lithographic apparatus and the surface of a substrate such that a radiation beam projected from the projection system can irradiate the surface of the substrate by passing through the immersion fluid, comprising a meniscus control surface and extraction parts both configured to extract the immersion fluid, the meniscus control surface being configured to support a meniscus of the immersion fluid between the meniscus control surface and the surface of the substrate in a first operating state and a second operating state, in the first operating state, the meniscus being fixed to the meniscus control surface, in the second operating state, the meniscus being movable along the meniscus control surface, Fluid handling system. Item 20: A fluid handling system for a lithographic apparatus, configured to confine the immersion fluid in a liquid confinement space between a part of the projection system in the lithographic apparatus and the surface of a substrate such that a radiation beam projected from the projection system can irradiate the surface of the substrate by passing through the immersion fluid, comprising a first extraction part and a second extraction part both configured to extract the immersion fluid, and a meniscus control surface between the first extraction part and the second extraction part, configured to extract the immersion fluid, comprising The meniscus control surface is configured to support the meniscus of the immersion liquid between the surface of the meniscus control surface and the surface of the substrate. Fluid handling system. Item 21: A lithographic apparatus comprising the fluid handling system according to any one of items 1 to 20. Item 22: The apparatus according to item 21, further comprising a positioning system configured to drive a substrate holder configured to support a substrate with respect to a projection system in a plane substantially parallel to the surface of the substrate. Item 23: A device manufacturing method in a lithographic apparatus having a substrate holder configured to hold a substrate, a projection system configured to project a radiation beam onto the substrate held by the substrate holder, and the fluid handling system according to any one of items 1 to 20, comprising: Using the fluid handling system to confine an immersion fluid in a space between at least a part of the fluid handling system and the surface of the substrate; Projecting a patterned radiation beam onto the substrate through the immersion fluid in the space; Supporting the meniscus of the immersion fluid between the meniscus control surface or damper of the fluid handling system and the substrate; Driving the substrate in a scan direction substantially perpendicular to the propagation direction of the radiation beam; Comprising: In a first operating state, the meniscus control surface is configured to hold the meniscus of the immersion fluid substantially stationary between the meniscus control surface and the surface of the substrate; In a second operating state, the meniscus control surface is configured to permit movement of the meniscus of the immersion fluid with respect to the meniscus control surface. Method. Item 24: A fluid handling system for a lithographic apparatus, comprising: So that the radiation beam projected from the projection system can irradiate the surface of the substrate by passing through the immersion fluid, the immersion fluid is restricted in the liquid confinement space between a part of the projection system in the lithographic apparatus and the surface of the substrate, comprising an electro-wetting structure, The electro-wetting structure comprises one or more electrodes arranged to apply an electro-wetting effect to at least a part of the substrate facing the surface of the fluid handling system, The one or more electrodes of the electro-wetting structure are controllable to change the contact angle and / or the contact line of the meniscus of the immersion fluid, A fluid handling system. Item 25: A lithographic apparatus comprising the fluid handling system according to item 24.

[0168] Although specific embodiments of the invention have been described above, it is understood that the invention may be practiced in a manner different from that described. The above description is for illustrative purposes only and is not intended to limit the invention. Thus, it will be apparent to those skilled in the art that modifications may be made to the described invention without departing from the scope of the following claims.

Claims

1. A fluid handling system for a lithographic apparatus, configured to confine the immersion fluid in a liquid confinement space between a part of the projection system in the lithographic apparatus and the surface of the substrate such that a radiation beam projected from the projection system can irradiate the surface of the substrate by passing through the immersion fluid, comprising a meniscus control surface for controlling the movement of the meniscus of the immersion fluid, in a first operating state, the meniscus control surface is configured to hold the meniscus of the immersion fluid substantially stationary between the meniscus control surface and the surface of the substrate, in a second operating state, the meniscus control surface is configured to allow movement of the meniscus of the immersion fluid, a fluid handling system.

2. further comprising a damper, in the second operating state, the damper is configured to support the movement of the meniscus of the immersion fluid between the surface of the damper and the surface of the substrate, The system according to claim 1.

3. The meniscus control surface comprises the surface of a microsieve or a porous member, and / or, The meniscus control surface comprises a wetted surface, and / or, further comprising a bypass flow path configured to provide a fluid flow along the opposite side of the meniscus control surface with respect to the substrate, The system according to claim 1 or 2.

4. a fluid inlet configured to supply a fluid flow to the bypass flow path, a fluid outlet configured to provide the fluid flow outside the bypass flow path, The system according to claim 3, further comprising.

5. The system according to claim 4, further comprising a flow control system configured to control the flow rate of the fluid through the fluid outlet.

6. The flow control system is configured to control the flow rate of the fluid through the fluid outlet to a first fluid flow rate or a second fluid flow rate, the first fluid flow rate is greater than the second fluid flow rate, the first fluid flow rate is for providing the first operating state, the second fluid flow rate is for providing the second operating state, The system according to claim 5.

7. The fluid flow in the bypass flow path is a liquid flow, the system according to any one of claims 3 to 6.

8. The meniscus control surface is hydrophilic, and / or, the damper surface is hydrophobic, and / or, the damper is provided with an electro-wetting structure, the electro-wetting structure comprises one or more electrodes arranged to apply an electro-wetting effect to at least a part of a substrate facing the surface of the fluid handling system, the one or more electrodes of the electro-wetting structure are controllable to change the contact angle and / or contact line of the meniscus of the immersion fluid, A system according to any one of claims 1 to 7.

9. comprising a fluid handling structure having an inner surface configured to confine the immersion fluid, further comprising a take-out portion configured to take out the immersion fluid, the meniscus control surface and the take-out portion are arranged radially away from the inner surface of the fluid handling structure, the take-out portion is arranged further away from the inner surface of the fluid handling structure than the meniscus control surface, and / or, in the second operating state, during use, the meniscus control surface is configured such that the meniscus moves relative to the meniscus control surface in response to movement of the substrate relative to the fluid handling system, A system according to any one of claims 1 to 8.

10. The system according to claim 9, wherein the take-out portion is configured such that during use only substantially gas flows therethrough and / or comprises a plurality of take-out portions.

11. each take-out portion is a first take-out portion, further comprising a second take-out portion configured to take out the immersion fluid, the second take-out portion is arranged radially away from the inner surface of the fluid handling structure, the second take-out portion is arranged closer to the inner surface of the fluid handling structure than the meniscus control surface, the meniscus control surface is arranged between the first and second take-out portions, A system according to claim 9 or 10.

12. comprising a plurality of second take-out portions, and / or, each second take-out portion is configured such that during use only substantially liquid flows therethrough, A system according to claim 11.

13. A fluid handling system for a lithographic apparatus, configured to confine the immersion fluid in a liquid confinement space between a part of the projection system in the lithographic apparatus and the surface of the substrate, such that a radiation beam projected from the projection system can irradiate the surface of the substrate by passing through the immersion fluid, comprising a meniscus control surface and a withdrawal part, both configured to withdraw the immersion fluid, the meniscus control surface being configured to support a meniscus of the immersion fluid between the meniscus control surface and the surface of the substrate, under a first operating state and a second operating state, in the first operating state, the meniscus being fixed to the meniscus control surface, in the second operating state, the meniscus being movable along the meniscus control surface, A fluid handling system.

14. A fluid handling system for a lithographic apparatus, configured to confine the immersion fluid in a liquid confinement space between a part of the projection system in the lithographic apparatus and the surface of the substrate, such that a radiation beam projected from the projection system can irradiate the surface of the substrate by passing through the immersion fluid, comprising a first withdrawal part and a second withdrawal part, both configured to withdraw the immersion fluid, a meniscus control surface between the first withdrawal part and the second withdrawal part, configured to withdraw the immersion fluid, comprising the meniscus control surface being configured to support a meniscus of the immersion liquid between the surface of the meniscus control surface and the surface of the substrate, A fluid handling system.

15. A lithographic apparatus comprising the fluid handling system according to any one of claims 1 to 14.

Images