THERMAL CONDITIONING SYSTEM AND LITHOGRAPHIC APPARATUS - Patent application

Abstract

A thermal conditioning system for a lithographic apparatus, the thermal conditioning system comprising: a body having conditioning channels for flowing a conditioning fluid for thermally conditioning the body and / or a component supported by or supporting the body; and a supply connection configured to supply the conditioning fluid to the conditioning channel of the body, the supply connection being shaped so that the conditioning fluid enters the body in a first direction and flows into the conditioning channel in a second direction different from the first direction, wherein the body comprises a chamber adjacent to the supply connection in the first direction, the chamber configured to at least reduce a force applied to the body by the supply connection.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to European Application No. 23151426.6, filed January 12, 2023, which is incorporated herein by reference in its entirety.

[0002] The present invention relates to a thermal conditioning system, a lithographic apparatus including a thermal conditioning system, a method of thermal conditioning, and a method of manufacturing a device including the method of thermal conditioning. [Background technology]

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

[0004]

[0004] As semiconductor manufacturing processes continue to advance, the dimensions of circuit elements have continually decreased, while the amount of functional elements, such as transistors, per device has steadily increased for decades, following a trend colloquially known as "Moore's Law." To keep up with Moore's Law, the semiconductor industry pursues technologies that allow it to create smaller and smaller features. To project a pattern onto a substrate, a lithography apparatus may use electromagnetic radiation. The wavelength of this radiation determines the minimum size of the features that can be patterned on the substrate. Wavelengths used include 365 nm (i-line), 248 nm, 193 nm, and 13.5 nm.

[0005]

[0005] Further improvements in the resolution of smaller features can be achieved by providing an immersion fluid with a relatively high refractive index, such as water, on the substrate during exposure. The effect of the immersion fluid is that the exposure radiation will have a shorter wavelength in the fluid than in a gas, and so allows for the imaging of smaller features. The effect of the immersion fluid can also be thought of as increasing the effective numerical aperture (NA) of the system and increasing the depth of focus. The immersion fluid may be confined to a localized area between the projection system of the lithographic apparatus and the substrate by a fluid handling structure.

[0006]

[0006] Further improvements in resolution of smaller features can be achieved by using EUV radiation in the projection beam, and the lithographic apparatus can be provided with an EUV reflector to reflect the beam. Summary of the Invention

[0007] In a semiconductor manufacturing process, one or more bodies of a lithographic apparatus may be thermally conditioned to control the temperature of the body or a component supported by the body or a component supporting the body. For example, a substrate may be supported on a substrate support, and the substrate support may be thermally conditioned. As another example, a reflector, such as an EUV reflector, may be thermally conditioned.

[0008]

[0008] Thermal conditioning fluids can apply forces to the body as they enter the body. These forces can undesirably affect the shape and / or position of the surface of the thermally conditioned component. For example, thermal conditioning fluids entering a substrate support substrate can undesirably affect the flatness of the substrate.

[0009]

[0009] It is an object of the present invention to reduce the effect of forces on a body caused by a thermal conditioning fluid entering the body.

[0010]

[0010] According to the present invention, there is provided a thermal conditioning system for a lithographic apparatus, the thermal conditioning system comprising: a body having conditioning channels for flowing a conditioning fluid for thermal conditioning the body and / or components supported by or supporting the body; a supply connection configured to supply a conditioning fluid to the conditioning channel of the body, the supply connection shaped so that the conditioning fluid enters the body in a first direction and enters the conditioning channel in a second direction different from the first direction; It is equipped with The body includes a chamber adjacent the supply connection in a first direction and configured to at least reduce a force applied to the body by the supply connection.

[0011]

[0011] The present invention also provides a lithographic apparatus including a thermal conditioning system.

[0012]

[0012] There is also provided in accordance with the present invention a method of thermal regulation, the method comprising: Entering a conditioning fluid into the body in a first direction through the supply connection; flowing the conditioning fluid into the conditioning channel of the body through the supply connection in a second direction different from the first direction, thereby supplying the conditioning fluid to the conditioning channel of the body; flowing a conditioning fluid through conditioning channels in the body to thermally condition the body and / or components supported by or supporting the body; It is equipped with The force applied to the body by the supply connection is at least reduced by a chamber in the body adjacent the supply connection in the first direction.

[0013]

[0013] The present invention also provides a method of manufacturing a device that includes a method of thermal regulation.

[0014] Further embodiments, features, and advantages of the present invention, as well as the structure and operation of the various embodiments, features and advantages of the present invention, are described in detail below with reference to the accompanying drawings. [Brief explanation of the drawings]

[0015]

[0015] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts, and in which:

[0016] [Figure 1] 1 shows a schematic diagram of a lithographic apparatus; [Figure 2] 10A and 10B schematically illustrate a cross-sectional view of a radially outer section of a substrate support; [Figure 3] 1 illustrates a schematic representation of a reflector in a lithographic apparatus; [Figure 4] 1 shows a schematic cross-sectional view of a supply connection for a body of a lithographic apparatus; [Figure 5] 10A and 10B schematically depict a cross-sectional view of an alternative supply connection for a body of a lithographic apparatus;

[0017]

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

[0018]

[0017] In this document, the terms "radiation" and "beam" are used to encompass all types of electromagnetic radiation, including ultraviolet radiation (for example wavelengths of 365 nm, 248 nm, 193 nm, 157 nm or 126 nm).

[0019] The terms "reticle," "mask," or "patterning device," as used herein, may be broadly interpreted as referring to a general-purpose patterning device that can be used to impart a patterned cross-section to an incoming radiation beam, corresponding to the pattern to be created in a target portion of a substrate. The term "light valve" can also be used in this context. Besides the classic mask (transmissive or reflective mask, binary mask, phase-shifting mask, hybrid mask, etc.), examples of other such patterning devices include programmable mirror arrays and programmable LCD arrays.

[0020] 1 schematically depicts a lithographic apparatus comprising: an illumination system (also called an illuminator) IL configured to condition a radiation beam B (e.g. UV radiation or DUV radiation), a mask support (e.g. mask table) MT configured to support a patterning device (e.g. mask) MA and connected to a first positioner PM configured to accurately position the patterning device MA according to certain parameters, a substrate support (e.g. substrate table) WT configured to hold a substrate (e.g. resist-coated wafer) W and connected to a second positioner PW configured to accurately position the substrate support WT according to certain parameters, and a projection system (e.g. refractive projection lens system) PS configured to project a pattern imparted to the radiation beam B by the patterning device MA onto a target portion C (e.g. comprising one or more dies) of the substrate W.

[0021]

[0020] In operation, the illumination system IL receives a radiation beam B from a radiation source SO, for example 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, or any combination thereof, for directing, shaping and / or controlling the radiation. The illuminator IL may be used to condition the radiation beam B, so that it has a desired spatial and angular intensity distribution across its cross-section in the plane of the patterning device MA.

[0022]

[0021] As used herein, the term "projection system" PS should be interpreted broadly as encompassing various types of projection systems, including refractive optical systems, catadioptric optical systems, anamorphic optical systems, magnetic optical systems, electromagnetic optical systems, and / or electrostatic optical systems, or any combination thereof, as appropriate to the exposure radiation used and / or other factors such as the use of an immersion liquid or a vacuum. Where the term "projection lens" is used herein, this may be considered as synonymous with the more general term "projection system" PS.

[0023] In an embodiment, the lithographic apparatus is of a type wherein at least a portion of the substrate W is covered by an immersion liquid having a relatively high refractive index (e.g. water) so as to fill an immersion space between the projection system PS and the substrate W, also known as immersion lithography. Further details regarding immersion techniques are found in U.S. Patent No. 6,952,253, which is incorporated herein by reference. In another embodiment, the lithographic apparatus is of a type that uses EUV radiation.

[0024] The lithographic apparatus may be of a type that includes two or more substrate supports WT (also referred to as "dual stage"). In such a "multi-stage" machine, the substrate supports WT may be used in parallel, and / or a substrate W on one substrate support WT may be used to expose a pattern on another substrate W while a preparation step for subsequent exposure of the substrate W is being performed on the other substrate support WT.

[0025] In addition to the substrate support WT, the lithographic apparatus LA may include a measurement stage (not shown in the drawings). The measurement stage is arranged to hold a sensor and / or a cleaning device. The sensor may be arranged to measure a property of the projection system PS or a property of the radiation beam B. The measurement stage may hold multiple sensors. The cleaning device may be arranged to clean part of the lithographic apparatus, for example part of the projection system PS or part of the system for providing immersion liquid. When the substrate support WT is remote from the projection system PS, the measurement stage may be moved below the projection system PS.

[0026] In operation, the radiation beam B is incident on the patterning device (e.g. mask) MA, which is held on the mask support MT, and is patterned by a pattern (design layout) present on the patterning device MA. Having traversed the mask MA, the radiation beam B passes through the projection system PS, which focuses the beam onto a target portion C of the substrate W. The second positioner PW and position measurement system IF can be used to accurately move the substrate support WT, for example, to position different target portions C at focused and aligned positions in the path of the radiation beam B. Similarly, the first positioner PM, and possibly further position sensors (not explicitly shown in FIG. 1 ), can be used to accurately position the patterning device MA with respect to the path of the radiation beam B. The patterning device MA and substrate W can be aligned using mask alignment marks M1, M2 and substrate alignment marks P1, P2. Although the illustrated substrate alignment marks P1, P2 occupy dedicated target portions, it is possible to position them in spaces between the target portions. When the substrate alignment marks P1, P2 are located between target portions C, they are known as scribe-lane alignment marks.

[0027] To clarify the invention, a Cartesian coordinate system is used. The Cartesian coordinate system has three axes: x, y, and z. Each of the three axes is orthogonal to the other two. Rotation about the x-axis is called Rx rotation. Rotation about the y-axis is called Ry rotation. Rotation about the z-axis is called Rz rotation. The x- and y-axes define a horizontal plane, while the z-axis is vertical. The Cartesian coordinate system is not limiting of the invention and is used for clarity only. Alternatively, another coordinate system, such as a cylindrical coordinate system, may be used to clarify the invention. The orientation of the Cartesian coordinate system may be different, for example, so that the z-axis has a component along the horizontal plane.

[0028] Immersion techniques have been introduced into lithography systems to enable improved resolution of smaller features. In an immersion lithography apparatus, a layer of immersion liquid, having a relatively high refractive index, is interposed in an immersion space between the apparatus's projection system PS (through which a patterned beam is projected towards the substrate W) and the substrate W. The immersion liquid covers at least that portion of the substrate W below the final element of the projection system PS. Thus, at least that portion of the substrate W that is to be exposed is immersed in the immersion liquid.

[0029] In commercial immersion lithography, the immersion liquid is water. Typically, the water is highly pure distilled water, such as ultrapure water (UPW) commonly used in semiconductor manufacturing plants. In immersion systems, the UPW is often purified and may undergo additional processing steps before being supplied to the immersion space as the immersion liquid. In addition to water, other liquids with high refractive indices, for example hydrocarbons such as fluorocarbons, and / or aqueous solutions, can be used as the immersion liquid. It is also envisioned that other fluids besides liquids will be used in immersion lithography.

[0030]

[0029] In this specification, the description refers to localized immersion where, in use, the immersion liquid is confined to an immersion space between the final element and a surface facing the final element. The facing surface is the surface of the substrate W or a surface of the support stage (or substrate support WT) that is flush with the surface of the substrate W. (It should be noted that in the following text, references to the surface of the substrate W also or instead refer to the surface of the substrate support WT, and vice versa, unless otherwise specified.) If the lithographic apparatus is of a type that uses immersion lithography, a fluid handling structure IH present between the projection system PS and the substrate support WT is used to confine the immersion liquid to the immersion space. The immersion space, filled with immersion liquid, is smaller than the top surface of the substrate W when viewed from above, and the immersion space remains substantially stationary while the substrate W and the substrate support WT move underneath it relative to the projection system PS.

[0031] In Figure 1 the fluid handling structure IH is shown with dashed lines because the fluid handling structure IH may not be included in the lithographic apparatus if the lithographic apparatus is of a type that uses EUV radiation. If the lithographic apparatus is of a type that uses EUV radiation, the radiation source may be configured to generate a beam of EUV radiation and to supply the EUV radiation beam to the lithographic apparatus. The EUV radiation beam is incident on a patterning device. As a result of interaction with the patterning device a patterned EUV radiation beam is generated which is projected onto a substrate.

[0032] Other immersion systems are also envisaged, such as unconfined immersion systems (so-called "all wet" immersion systems) and bath immersion systems. In an unconfined immersion system, the immersion liquid covers more than the surface below the final element. The liquid outside the immersion space is present as a thin liquid film. The liquid may cover the entire surface of the substrate W, or may even cover the substrate W and a substrate support WT that is coplanar with the substrate W. In a bath-type system, the substrate W is fully immersed in a bath of immersion liquid.

[0033]

[0032] The fluid handling structure IH is a structure that supplies and removes immersion liquid to and from the immersion space, thereby confining the immersion liquid in the immersion space. It includes features that are part of a fluid supply system. The arrangement disclosed in PCT Patent Application Publication No. WO 99 / 49504 is an early fluid handling structure that comprises pipes that supply or remove immersion liquid from the immersion space and that move in response to relative movements of a stage below the projection system PS. In more recent designs, the fluid handling structure IH extends along at least part of the boundary of the immersion space between the final element of the projection system PS and the substrate support WT or substrate W, so as to partly define the immersion space.

[0034]

[0033] An immersion liquid may be used as the immersion fluid. In that case, the fluid handling structure IH may be a liquid handling system. With regard to the above description, references in this paragraph to features defined with respect to a fluid may be understood to include features defined with respect to a liquid.

[0035] The lithographic apparatus has a projection system PS. During exposure of a substrate W, the projection system PS projects patterned radiation onto the substrate W. To reach the substrate W, the path of a radiation beam B passes from the projection system PS through immersion liquid that is confined by a fluid handling structure IH between the projection system PS and the substrate W. The projection system PS has a lens element at the end of the beam path, which lens element comes into contact with the immersion liquid. This lens element that comes into contact with the immersion liquid may be called the "final lens element" or "final element". The final element is at least partly surrounded by the fluid handling structure IH. The fluid handling structure IH may confine immersion liquid below the final element and above a facing surface.

[0036] As shown in Figure 1, the lithographic apparatus includes a controller 500. The controller 500 is configured to control the substrate support WT.

[0037]

[0036] Figure 2 illustrates a part of a lithographic apparatus that is useful for demonstrating features of the present invention. The arrangement shown in Figure 2 and described below may be applied to the lithographic apparatus shown in Figure 1, described above. Figure 2 shows a cross-section of a substrate support 20 and a substrate W. In an embodiment, the substrate support 20 is provided with one or more conditioning channels 61 of a thermal conditioner, which will be described in more detail below. A gap 5 exists between the edge of the substrate W and the edge of the substrate support 20. When the edge of the substrate W is being imaged, or at other times, such as when the substrate W is initially moving under the projection system PS (as described above), any immersion space that has been filled with liquid by (for example) the fluid handling structure IH will pass at least partially over the gap 5 between the edge of the substrate W and the edge of the substrate support 20. This may cause liquid from the immersion space to enter the gap 5.

[0038] The substrate W is held by a support 21 (e.g. a pimple or burl table) which comprises one or more burls 41 (i.e. protrusions from its surface). The support 21 is an example of an object holder. Another example of an object holder is a mask support. Negative pressure applied between the substrate W and the substrate support 20 helps to ensure that the substrate W is held firmly in place. However, if immersion liquid gets between the substrate W and the support 21 this can cause difficulties, especially when unloading the substrate W.

[0039] To deal with immersion liquid that enters the gap 5, at least one drain 10, 12 is provided at the edge of the substrate W to remove the immersion liquid that enters the gap 5. Although two drains 10, 12 are shown in the embodiment of Figure 2, there may be only one drain or there may be more than two drains. In one embodiment, each of the drains 10, 12 is annular so as to surround the entire periphery of the substrate W. In Figure 2, the two drains 10, 12 are shown with dashed lines because the two drains 10, 12 may not be included in the lithographic apparatus if the lithographic apparatus is of a type that uses EUV radiation.

[0040] The main function of the first drain 10 (radially outward from the edge of the substrate W / supports 21) is to help prevent gas bubbles from entering the immersion space where liquid of the fluid handling structure IH is present. Such bubbles could adversely affect imaging of the substrate W. The first drain 10 is present to help avoid gas in the gap 5 escaping into the immersion space in the fluid handling structure IH. If gas escapes into the immersion space, bubbles may become suspended in the immersion space. Such bubbles could cause imaging errors if they are in the path of the projection beam. The first drain 10 is configured to remove gas from the gap 5 between the edge of the substrate W and the edge of the recess in the substrate support 20 in which the substrate W is placed. The edge of the recess in the substrate support 20 may be defined by a cover ring 101, which may be optionally separate from the supports 21 of the substrate support 20. The cover ring 101 may be shaped as a ring when viewed from above and surrounds the outer edge of the substrate W. The first drain 10 extracts mainly gas and a small amount of immersion liquid.

[0041] A second drain 12 (radially inward of the edge of the substrate W / support 21) is provided to help prevent liquid progressing from the gap 5 under the substrate W from interfering with efficient release of the substrate W from the substrate table WT after imaging. Providing the second drain 12 reduces or eliminates problems that can arise due to liquid progressing under the substrate W.

[0042] As shown in Figure 2, in one embodiment, the lithographic apparatus includes a first extraction channel 102 for passing the two-phase flow. The first extraction channel 102 is formed in the block. The first and second drains 10, 12 are each provided with a respective opening 107, 117 and a respective extraction channel 102, 113. The extraction channels 102, 113 are in fluid communication with the respective openings 107, 117 through respective passages 103, 114. In Figure 2, the two seals around the opening 117 are shown with dashed lines because the two seals may not be included in the lithographic apparatus if the lithographic apparatus is of a type that uses EUV radiation.

[0043] 2, the cover ring 101 has a top surface. The top surface extends circumferentially around the substrate W on the support 21. When the lithographic apparatus is in use, the substrate support 20 moves relative to the fluid handling structure IH. During this relative movement, the fluid handling structure IH moves across the gap 5 between the cover ring 101 and the substrate W. In an embodiment, the relative movement is caused by the substrate support 20 moving below the fluid handling structure IH. In an alternative embodiment, the relative movement is caused by the fluid handling structure IH moving above the substrate support 20. In a further alternative embodiment, the relative movement is provided by both movement of the substrate support 20 below the fluid handling structure IH and movement of the fluid handling structure IH above the substrate support 20.

[0044]

[0043] Figure 3 shows a schematic representation of a reflector in a lithographic apparatus. The arrangement shown in Figure 3 and described below may be applied to the lithographic apparatus shown in Figure 1 and described above.

[0045] FIG. 3 illustrates, in partial cross section, a reflector that can be used in a reflective or catadioptric system of a lithographic apparatus, such as the illumination system IL or the projection system PS. The reflective optical system is useful in lithographic apparatuses that use EUV radiation in the projection beam B. The reflector 200 comprises a reflector substrate 201 formed of a material with high stiffness and a low coefficient of thermal expansion, such as Zerodur™ or ULE™. A multilayer coating 202 is provided on the reflector substrate 201 and takes the form of a distributed Bragg reflector for reflecting EUV radiation at near-normal incidence. The reflective surface 203 of the multilayer coating 202 forms the main surface of the reflector 200, since deformation of the reflective surface 203 affects the pattern projected onto the substrate W. In particular, changes in the global orientation of the reflective surface 203 will change the position of the pattern projected onto the substrate W. Local variations in the angle of the reflective surface 203 will distort the pattern projected onto the substrate W. Small expansions or contractions of the reflector substrate 200 may not have a significant effect on the projected pattern unless they result in changes in the orientation or surface contour of the reflective surface 203. The reflector 200 may be mounted on an active mount 204 that is controlled to maintain a desired orientation of the reflective surface 203.

[0046] Despite the use of the multi-layer coating 202, the reflectivity of the EUV reflector is only around 70%. Therefore, the EUV reflector experiences significant thermal loads during use, and active cooling thereof is desirable. Similar to the substrate support 20 of FIG. 2, in one embodiment, the reflector substrate 201 includes one or more conditioning channels 61 of a thermal conditioner. The conditioning channels 61 may have complex paths within the reflector substrate 201 to ensure that all portions of the reflector 200 are adequately conditioned. Local deformations of the back surface 205 and global growth of the reflector substrate 201 will not significantly affect the projected pattern.

[0047]

[0046] Figure 4 schematically illustrates a cross-sectional view of a supply connection 50 for a body of a component of a lithographic apparatus. The arrangement shown in Figure 4 and described below may be applied to the lithographic apparatus shown in Figure 1 described above. In Figure 4, the body to which the supply connection 50 applies is the support 21 of the substrate support 20. The support 21 may, for example, be of the type shown in Figure 2. Below, the supply connection 50 and its application to the body will be described in the context of the body being such a support 21. The supply connection 50 may additionally or alternatively be applied to one or more other bodies of the lithographic apparatus, such as, for example, the reflector 200 shown in Figure 3.

[0048] FIG. 4 schematically illustrates a cross-sectional view of a thermal conditioning system. The thermal conditioning system is for a lithographic apparatus such as the lithographic apparatus shown in FIG. 1. As shown in FIG. 4, in one embodiment, the thermal conditioning system comprises a body such as the support 21. In one embodiment, the support 21 comprises at least one conditioning channel 61. The conditioning channel 61 is for flowing a conditioning fluid. In one embodiment, the conditioning fluid is for thermal conditioning the support 21. The conditioning channel 61 is connected to a supply connection 50 within the support 21. Additionally or alternatively, in one embodiment, the conditioning fluid is for thermal conditioning a component supported by the support 21. For example, the support 21 may support a substrate W. The conditioning fluid may be for thermal conditioning the substrate W. Additionally or alternatively, in one embodiment, the conditioning fluid is for thermal conditioning a component supporting the body.

[0049] The conditioning fluid may be a liquid, such as water. Alternatively, the conditioning fluid may be a gas. The conditioning fluid flows through the conditioning channels 61 and exchanges heat with the support 21. In one embodiment, the controller 500 is configured to control the temperature of the conditioning fluid to control the temperature of the support 21 and / or the substrate W. The conditioning fluid may be used to remove heat from the support 21 or to provide heat to the support 21. The thermal conditioning system allows the temperature of the support 21 and the substrate W to be controlled. This helps to control the shape of the surface of the substrate W, for example to improve its flatness. In the case where the body is a reflector 200, the thermal conditioning system may improve the flatness or other intended shape of the surface of the reflector 200.

[0050] 4, in one embodiment, the thermal conditioning system includes a supply connection 50. The supply connection 50 is configured to supply a conditioning fluid to a conditioning channel 61 of the support 21. The supply connection 50 is configured to allow the conditioning fluid to flow into the conditioning channel 61.

[0051] 4, in one embodiment, supply connection 50 is configured to receive the conditioning fluid from fluid manifold 70. Fluid manifold 70 may include one or more conduits, such as pipes, for supplying the conditioning fluid to the thermal conditioning system. Supply connection 50 may be disposed in the conditioning fluid circuit between fluid manifold 70 and conditioning channel 61.

[0052] As shown in Figure 4, in one embodiment, the supply connection 50 is shaped so that the conditioning fluid enters the support 21 in a first direction. In the drawing orientation shown in Figure 4, the first direction is vertically upward, although it is not necessary that the first direction be vertical. The first direction (i.e., the angle of the conduit of the supply connection 50) may be different from that shown in Figure 4.

[0053] As shown in FIG. 4, in one embodiment, the supply connection 50 is shaped so that the conditioning fluid enters the conditioning channel 61 in a second direction. The second direction is different from the first direction. In the drawing orientation shown in FIG. 4, the second direction is horizontal, from right to left. However, the second direction need not be horizontal. The second direction (i.e., the angle of the conditioning channel 61) may be different from that shown in FIG. 4.

[0054] As shown in Figure 4, in one embodiment, the support 21 comprises a chamber 62. The chamber 62 is adjacent to the supply connection 50. In one embodiment, the chamber 62 is adjacent to the supply connection 50 in a first direction. In the configuration shown in Figure 4, the first direction is vertical. The chamber 62 is adjacent to the supply connection 50 in the vertical direction. The chamber 62 is above the supply connection 50. In an alternative embodiment, the first direction is different from vertical, in which case the chamber 62 may not be directly above the supply connection 50.

[0055] When the conditioning fluid enters the support 21 via the supply connection 50, the conditioning fluid applies a force to the support 21. The force may be applied in a first direction, i.e., in the direction in which the conditioning fluid enters the support 21. This force may adversely affect the shape and / or position of the support 21 and / or the substrate W. For example, this force may undesirably reduce the flatness of the surface of the substrate W facing away from the support 21. In one embodiment, the chamber 62 is configured to counteract this force. The chamber 62 may be a buffer chamber configured to act as a buffer.

[0056] In one embodiment, the chamber 62 is configured to reduce the force applied to the support 21 by the supply connection 50. The chamber 62 may be configured as a mechanical / dynamic buffer to isolate / attenuate any disturbances in a first direction due to the conditioning fluid pressure propagating through the supply connection 50. In one embodiment, the gas in the chamber 62 is compressed when the force due to the conditioning fluid is applied. An embodiment of the present invention is expected to reduce the undesirable effects of any force applied to the body by the ingress of the conditioning fluid. This may help to improve the precision with which the shape and / or position of the support 21 and / or the substrate W can be controlled. For example, in the context of the reflector 200, reducing pressure fluctuations may reduce any adverse effects on the reflector's line of sight and ultimately overlay penalties.

[0057]

[0056] As shown in Figure 4, in one embodiment, the support 21 is substantially plate-shaped. The support 21 may have a plate shape. The plate shape may be in a plane. For example, the support 21 illustrated in Figure 4 has a plate shape in a plane that extends horizontally and faces towards and away from the page. If the body is, for example, a reflector 200 as shown in Figure 3, for example, the plate shape may be angled with respect to the horizontal. The surface of the reflector 200 may not be completely flat, but may be substantially flat.

[0058] As shown in FIG. 4 , in one embodiment, the angle between the second direction and a plane parallel to the plate shape is smaller than the angle between the second direction and a normal to the plane. In the configuration shown in FIG. 4 , the second direction is horizontal, and the plate shape extends horizontally. The angle between the second direction and the plane parallel to the plate shape is substantially zero. In an alternative embodiment, the angle between the second direction and the plane parallel to the plate shape is non-zero. For example, in one embodiment, the angle between the second direction and the plane parallel to the plate shape is at most 20°, optionally at most 10°, optionally at most 5°, optionally at most 2°, and optionally at most 1°. A smaller angle may allow the conditioning fluid to thermally condition the support 21 more uniformly across the support 21.

[0059] 4, the second direction is horizontal and the normal to the plane parallel to the plate shape is vertical. The angle between the second direction and this normal is substantially a right angle, i.e., 90°. In an alternative embodiment, the angle between the second direction and the normal to the plane parallel to the plate shape is less than 90°. For example, in one embodiment, the angle between the second direction and the normal to the plane parallel to the plate shape is at least 45°, optionally at least 70°, optionally at least 80°, optionally at least 85°, and optionally at least 88°. A smaller angle can reduce the lateral space occupied by the supply connection 50.

[0060] 4, the conditioning fluid exits the supply connection 50 in a horizontal direction (entering the internal conditioning channel 61 of the support 21). In one embodiment, the supply connection 50 is configured so that the flow lines of the conditioning fluid within the supply connection follow a substantially "L" shape. As shown in FIG. 4, in one embodiment, the supply connection 50 has a closed end. Conditioning fluid pressure acts in a first direction on a first end 52 (also known as the inner body top) of the supply connection 50 (instead of acting on the support 21).

[0061] 4, in one embodiment, chamber 62 is immediately adjacent to first end 52 of supply connection 50. Gas in chamber 62 contacts first end 52. Alternatively, chamber 62 may be indirectly adjacent to supply connection 50. For example, there may be a thin section of support 21 between chamber 62 and supply connection 50. This section is thin enough that chamber 62 is compressed when conditioning fluid entering support 21 applies a force in a first direction.

[0062] 4, in one embodiment, the supply connection 50 is shaped so that conditioning fluid flowing substantially straight through the supply connection 50 to enter the support 21 along a first direction strikes an inner surface of the supply connection 50. By striking the inner surface, the conditioning fluid applies a force. This force is indicated by the force arrows 71 shown in FIG. 4. This force can be reduced, e.g., attenuated, by the chamber 62.

[0063] 4, in one embodiment, supply connection 50 comprises a conduit portion 51. Conditioning fluid flows through conduit portion 51. Conduit portion 51 may have a longitudinal direction that may define a general flow direction of the conditioning fluid entering support 21. Conduit portion 51 may be shaped so that the conditioning fluid flows in a substantially straight direction as it enters support 21. Of course, some turbulence may exist in the flow of the conditioning fluid. In one embodiment, supply connection 50 may be slightly bent / curved.

[0064] 4, in one embodiment, the supply connection 50 comprises a conduit section 51 formed as a pipe. An embodiment of the present invention is expected to provide a simple design for the supply connection 50. This may improve the reliability of the supply connection 50 and / or reduce the cost of manufacturing the supply connection 50.

[0065] As shown in FIG. 4 , in one embodiment, the supply connection 50 is secured to the fluid manifold 70. In one embodiment, the supply connection 50 is anchored to the fluid manifold 70, for example, by a bayonet lock. However, it is not necessary for the supply connection 50 to be directly secured to the fluid manifold 70. The conditioning fluid pressure acting on the first end 52 of the supply connection 50 can be balanced, at least in part, by a force due to the connection between the supply connection 50 and the fluid manifold 70 (or between the supply connection 50 and another external body). Such a force is indicated in FIG. 4 by force arrows 72. Such a force can counteract any counterforce when fluid pressure is applied due to conditioning fluid entering the supply connection 50. Such a force can be present in an anchorage, such as a thread, between the conduit portion 51 and the fluid manifold 70. One embodiment of the present invention is expected to at least reduce, and optionally eliminate, a force in a first direction due to conditioning fluid pressure acting on the support 21. In an alternative embodiment, the connection between the conduit portion 51 and the fluid manifold 70 is substantially force-free. When fluid pressure is applied due to conditioning fluid entering the supply connection 50, there is substantially no reaction force.

[0066] As shown in FIG. 4, in one embodiment, the chamber 62 is fluidly connectable to an environment external to the support 21. As shown in FIG. 4, in one embodiment, a vent passage 63 (or vent channel / hole) is provided to fluidly connect the chamber 62 to the ambient environment. The support 21 may include a vent passage 63 configured to fluidly connect the chamber 62 to the ambient environment of the support 21. The vent passage 63 may be permanently open. Alternatively, the vent passage 63 may be controllably opened and closed, for example, by a valve. In one embodiment, the connection between the supply connection 50 and the support 21 is substantially force-free. When fluid pressure is applied by the conditioning fluid entering the support 21, there is substantially no reaction force. The connection between the chamber 62 and the ambient environment reduces or eliminates any pressure difference between the two ends of the supply connection 50.

[0067] An embodiment of the present invention is expected to improve the isolation / damping performance of chamber 62. By connecting chamber 62 to the ambient environment, gas may exit chamber 62 and enter the ambient environment when chamber 62 is compressed. This reduces the possibility that chamber 62 acts like a spring that mechanically couples support 21 to supply connection 50.

[0068] As shown in Figure 4, in one embodiment, the ventilation passage 63 may be created through the support 21. As shown in Figure 4, in one embodiment, the support 21 is formed as a single piece. Alternatively, as shown in Figure 5, the support 21 may be two pieces fixed to each other. The support 21 may comprise a first piece 22 and a second piece 23. The first piece 22 may be bonded to the second piece 23 to form the support 21. A bonding layer may be provided between the first piece 22 and the second piece 23.

[0069] In one embodiment, the ventilation passages 63 are provided in the bonding layer between the first part 22 and the second part 23. This may make the ventilation passages 63 easier to create.

[0070] However, it is not essential that the ventilation passage 63 be provided. In an alternative embodiment, the chamber 62 forms a closed / compressed gas pocket. The chamber 62 may also be embodied as a pocket of gas, for example a thin layer of air. By omitting the ventilation passage 63, the thermal regulation system may be easier to manufacture.

[0071] As shown in FIG. 4 , in one embodiment, the thermal conditioning system includes a seal configured to seal the outlet of the supply connection 50 from the environment external to the chamber 62 and / or the support 21. For example, FIG. 4 shows a first seal element 53 above the outlet (i.e., where the conditioning fluid enters the conditioning channel 61 from the supply connection 50). The first seal element 53 can be between the outlet and the chamber 62. The first seal element 53 is configured to seal the outlet of the supply connection 50 from the environment external to the chamber 62 and the support 21. In one embodiment, the first seal element 53 is an O-ring. As shown in FIG. 4 , in one embodiment, the first seal element 53 is disposed in a plane substantially perpendicular to the first direction.

[0072] FIG. 4 shows a second sealing element 56 below the outlet. The seal includes a second sealing element 56 between the outlet and an opening in the support 21 through which the supply connection 50 is inserted. The second sealing element 56 is configured to seal the outlet of the supply connection 50 from the environment outside the support 21. In one embodiment, the second sealing element 56 is an O-ring. As shown in FIG. 4, in one embodiment, the second sealing element 56 is arranged in a plane substantially perpendicular to the first direction. In one embodiment, the two sealing elements 53, 56 are arranged substantially perpendicular to the first direction and are positioned on either side of the adjustment channel 61 in the second direction. In one embodiment, the two sealing elements 53, 56 are configured so that the sum of the fluid forces on the support 21 in the first direction is substantially zero.

[0073] 4, in one embodiment, the supply connection 50 is fixed to the support 21 via at least one sealing element 53, 56. In one embodiment, the supply connection 50 is fixed to the support 21 via at least two sealing elements 53, 56, one on each side of the adjustment channel 61.

[0074]

[0073] Figure 5 schematically illustrates a cross-sectional view of an alternative supply connection 50 for a body of a component of a lithographic apparatus. The arrangement shown in Figure 5 and described below may be applied to the lithographic apparatus shown in Figure 1 described above. In Figure 5, the body to which the supply connection 50 is applied is the support 21 of the substrate support 20. The support 21 may, for example, be of the type shown in Figure 2. Below, the supply connection 50 and its application to the body will be described in the context of the body being such a support 21. The supply connection 50 may additionally or alternatively be applied to one or more other bodies of a component of the lithographic apparatus, such as, for example, the reflector 200 shown in Figure 3.

[0075] 5, in one embodiment, the supply connection 50 comprises a first end 52 and a conduit portion 51. The first end 52 and the conduit portion 51 are independently secured to the support 21, such that the first end 52 is anchored to the conduit portion 51 only via the support 21. There is substantially no direct force between the conduit portion 51 and the first end 52.

[0076]

[0075] An embodiment of the present invention is expected to improve the reliability of manufacturing thermal regulating systems. As shown in Figure 5, parts 22, 23 of support 21 may include holes into which supply connection 50 fits. There may be some unintentional misalignment between these holes. By providing that first end 52 and conduit portion 51 are not directly secured to one another (e.g., are not integrally formed), there is a greater tolerance for misalignment of the holes in support 21.

[0077]

[0076] For example, as shown in Figure 5, in one embodiment, the first end 52 is fixed to the support 21 (e.g., to the first part 22 of the support 21) via a first sealing element 53. In one embodiment, the sealing element 53 is an O-ring. In one embodiment, the conduit portion 51 is fixed to the support 21 (e.g., to the second part 23 of the support 21) via a second sealing element 56. In one embodiment, the sealing element 56 is an O-ring. The first end 52 is not directly connected to the conduit portion 51. The position of the first end 52 relative to the conduit portion 51 is fixed via the first part 22 and the second part 23 of the support 21.

[0078]

[0077] It is not necessary for the support 21 to be in two parts. In an alternative embodiment, the support 21 is formed as a single layer rather than a multilayer.

[0079] 5, in one embodiment, supply connection 50 includes second end 55. Second end 55 is configured to be secured to a fluid supply, such as a fluid manifold 70, to supply the conditioning fluid. For example, as shown in FIG. 5, in one embodiment, second end 55 is secured to fluid manifold 70 via a third sealing element 57. In one embodiment, third sealing element 57 is an O-ring.

[0080] 5, in one embodiment, the supply connection 50 includes a mechanical connector 54. The mechanical connector 54 is configured to mechanically connect the first end 52 to the second end 55 through the conduit portion 51. The mechanical connector 54 extends through the conduit portion 51 without contacting the conduit portion 51. The conduit portion 51 surrounds the mechanical connector 54. The mechanical connector 54 is configured to mechanically connect the ends of the supply connection 50 to transfer forces therebetween. This allows for balancing of forces at both ends of the supply connection 50. This reduces the overall force on the support 21 due to the supply connection 50 and the flow of the conditioning fluid.

[0081]

[0080] There may be some misalignment between the hole into which first end 52 fits and the hole into which second end 55 fits. Mechanical connector 54 is configured to flex laterally to accommodate any such misalignment.

[0082] 5, in one embodiment, the mechanical connector 54 is secured directly to the first end 52. The mechanical connector 54 may also be integrally formed with the first end 52.

[0083] 5, in one embodiment, the mechanical connector 54 forms a tube. The tube is configured to fluidly connect the chamber 62 to a volume 73 beyond the second end 55. The volume can be a pocket of gas, such as air. This allows the chamber 62 to be vented without the need for the vent passage 63 shown in FIG. 4. The tube is configured to equalize pressure across the conduit portion 51 of the supply connection 50.

[0084] As shown in Figure 5, in one embodiment, chamber 62 is fluidly connected to the environment external to support 21 via tubing formed by mechanical connector 54. As shown in Figure 5, in one embodiment, vent holes 74 are provided to fluidly connect volume 73 to the ambient environment. Mechanical connector 54 forms a vent tube that passes through supply connection 50 via bottom vent hole 74.

[0085] 5, the ventilation passage 63 as shown in FIG. 4 can be omitted while still allowing ventilation of the chamber 62. An embodiment of the present invention is expected to reduce the complexity of the design of the support 21. In particular, there is no need to create additional holes / channels in the support 21.

[0086]

[0085] The support 21 can be formed from any material known in the art. For example, the support 21 can be formed from SiSiC, SiC, AlN, Zerodur™, cordierite, or any other suitable ceramic or glass-ceramic material. The support 21 can be coated. The type of coating is not particularly limited and can be any coating known to those skilled in the art to be suitable for the application. For example, the support 21 can be coated with diamond or diamond-like carbon (DLC).

[0087] The present invention may be embodied as a method of thermal conditioning. In one embodiment, the method comprises entering a conditioning fluid into a body, such as the support 21, in a first direction through a supply connection 50. In one embodiment, the method comprises flowing the conditioning fluid into a conditioning channel 61 of the support 21 in a second direction, different from the first direction, through the supply connection 50, thereby supplying the conditioning fluid to the conditioning channel 61 of the support 21. In one embodiment, the method comprises flowing the conditioning fluid through the conditioning channel 61 to thermally condition the support 21 and / or a component, such as a substrate W, supported by or supporting the support 21. In one embodiment, a force applied to the support 21 by the supply connection 50 is reduced by a chamber 62 of the support 21 adjacent the supply connection 50 in the first direction.

[0088] In one embodiment, the method comprises venting the chamber 62 to / from the environment external to the support 21.

[0089] In one embodiment, the method comprises at least partially inserting the supply connection 50 into the support 21 in a first direction.

[0090]

[0089] In one embodiment, the method comprises fixing the supply connection 50 to the support 21.

[0091]

[0090] In one embodiment, the fixing comprises fixing the first end 52 of the supply connection 50 to the support 21 and fixing the conduit portion 51 independently to the support 21, whereby the first end 52 is fixed to the conduit portion 51 only via the support 21.

[0092]

[0091] In one embodiment, the method comprises fixing a first part (or body portion) 22 to a second part (or body portion) 23 to form a support 21, wherein a first end 52 is fixed to the first part 22 and a conduit portion 51 is fixed to the second part 23.

[0093] The present invention may provide a lithographic apparatus, which may have any / all of the other features or components of the lithographic apparatus described above. For example, the lithographic apparatus may optionally comprise at least one or more of a radiation source SO, an illumination system IL, a projection system PS, a substrate support WT, etc.

[0094] In particular, the lithographic apparatus may comprise a projection system PS configured to project a radiation beam B towards a region of a surface of a substrate W. The lithographic apparatus may further comprise a substrate support as described in any of the above embodiments and variants.

[0095]

[0094] Although specific reference may be made in this text to the use of lithographic apparatus in the manufacture of ICs, it will be appreciated that the lithographic apparatus described herein have other applications, such as in 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, etc.

[0096] Where the context permits, embodiments of the present invention may be implemented in hardware, firmware, software, or any combination thereof. Embodiments of the present invention may also be implemented as instructions stored on a machine-readable medium, which may be read and executed by one or more processors. A machine-readable medium may include any mechanism for storing or transmitting information in a form readable by a machine (e.g., a computing device). For example, machine-readable media 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 propagated signals (e.g., carrier waves, infrared signals, digital signals, etc.), and others. Furthermore, firmware, software, routines, and instructions may be described herein as performing certain actions. However, it should be understood that such description is merely for convenience and that such actions actually result from computing devices, processors, controllers, or other devices executing the firmware, software, routines, instructions, etc., and that, in performing these actions, actuators or other devices may interact with the physical world.

[0097] Although specific reference is made herein to embodiments of the invention in relation to lithographic apparatus, embodiments of the invention may also be used in other apparatus. Embodiments of the invention may form part of a mask inspection apparatus, a metrology apparatus, or any apparatus that measures or processes objects such as wafers (or other substrates) or masks (or other patterning devices). These apparatus are sometimes generically referred to as lithography tools.

[0098]

[0097] Although particular reference has been made to the use of embodiments of the present invention in the field of optical lithography, it should be understood that the present invention may also be used in other fields, such as imprint lithography, depending on the context, and is not limited to optical lithography.

[0099]

[0098] While specific embodiments of the present invention have been described above, it should be understood that the present invention may be practiced in other ways. The above description is intended to be illustrative and not limiting. Accordingly, it will be apparent to those skilled in the art that modifications may be made to the invention as described without departing from the scope of the appended claims.

Claims

1. 1. A thermal conditioning system for a lithographic apparatus, comprising: a body having conditioning channels for flowing a conditioning fluid for thermal conditioning the body and / or components supported by or supporting the body; a supply connection configured to supply the conditioning fluid to the conditioning channel of the body, the supply connection shaped so that the conditioning fluid enters the body in a first direction and enters the conditioning channel in a second direction different from the first direction; It is equipped with The thermal regulation system, wherein the body comprises a chamber adjacent the supply connection in the first direction, the chamber configured to at least reduce a force applied to the body by the supply connection.

2. 2. The thermal regulating system of claim 1, wherein the body is substantially plate-shaped, and the angle between the second direction and a plane parallel to the plate shape is smaller than the angle between the second direction and a normal to the plane, and preferably the angle between the second direction and the first direction is at least 45°.

3. 3. The thermal regulating system of claim 1 or 2, wherein the supply connection is shaped so that the conditioning fluid flowing substantially straight through the supply connection to enter the body along the first direction strikes an inner surface of the supply connection, and / or the chamber is fluidly connectable to an environment external to the body, and / or the supply connection has a first end and a conduit portion independently fixed to the body, whereby the first end is fixed to the conduit portion only via the body.

4. 4. The thermal regulation system of claim 3, wherein the supply connection comprises a second end configured to be secured to a fluid supply for supplying the conditioning fluid, and preferably the supply connection comprises a mechanical connector configured to mechanically connect the first end to the second end through the conduit portion, and preferably the mechanical connector comprises a tube configured to fluidly connect the chamber to a volume beyond the second end, and preferably the chamber is fluidly connected to an environment external to the body via the tube formed by the mechanical connector.

5. 5. A thermal regulation system according to claim 1, wherein the body comprises a ventilation passage configured to fluidly connect the chamber to an environment external to the body, and / or a seal configured to seal the outlet of the supply connection from the environment external to the chamber and / or the body.

6. The thermal regulation system of claim 5 , wherein the seal comprises a first sealing element between the outlet and the chamber, preferably the first sealing element being disposed in a plane substantially perpendicular to the first direction.

7. 7. The thermal regulation system of claim 5 or 6, wherein the seal comprises a second sealing element between the outlet and an opening in the body through which the supply connection is inserted, preferably the second sealing element being arranged in a plane substantially perpendicular to the first direction.

8. The thermal regulation system of claim 1 , wherein the body is a substrate support configured to support a substrate, or the body is an optical reflector or a reflector support configured to support an optical reflector.

9. A lithographic apparatus comprising a thermal conditioning system according to any one of claims 1 to 8.

10. 1. A method of thermal regulation comprising: entering a conditioning fluid into the body in a first direction through the supply connection; flowing the conditioning fluid through the supply connection into the conditioning channel of the body in a second direction different from the first direction, thereby supplying the conditioning fluid to the conditioning channel of the body; flowing the conditioning fluid through the conditioning channels of the body to thermally condition the body and / or components supported by or supporting the body; It is equipped with The method, wherein the force applied to the body by the supply connection is at least reduced by a chamber in the body adjacent the supply connection in the first direction.

11. venting the chamber to / from an environment external to the body and / or at least partially inserting the supply connection into the body in the first orientation. The method of claim 10, comprising:

12. The method of claim 11 , further comprising securing the supply connection to the body.

13. 13. The method of claim 12, wherein said securing comprises securing a first end of said supply connection to said body and independently securing a conduit portion to said body, whereby said first end is anchored to said conduit portion solely through said body.

14. 14. The method of claim 13, comprising securing a first body portion to a second body portion to form the body, wherein the first end is secured to the first body portion and the conduit portion is secured to the second body portion.

15. A method for manufacturing a device comprising the method of thermal regulation according to any one of claims 10 to 14.

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