Magnetic levitation locator assembly for use in lithographic apparatus, lithographic apparatus having such assembly, method of operating such assembly, and method of manufacturing apparatus including method of operating or using such apparatus

Abstract

The present disclosure relates to an assembly for a lithographic apparatus, the assembly comprising: a thermal conditioning plate; the plurality of superconducting coils are used for enabling the objective table to be subjected to magnetic suspension and linear displacement on the superconducting coils, and the plurality of superconducting coils are in thermal contact with the thermal adjusting plate; wherein: the thermal conditioning plate includes a first internal passage for containing a first refrigerant and a second internal passage for containing a second refrigerant; and the first internal channel and the second internal channel are thermally coupled with each other and are in fluid isolation with each other, so that heat transfer between the first refrigerant and the second refrigerant is realized while the first refrigerant and the second refrigerant are in fluid isolation with each other.

Description

A magnetic levitation positioner assembly used in a photolithography apparatus, a photolithography apparatus having the assembly, a method for operating the assembly, and a method for manufacturing the apparatus including the method of operating or using the apparatus. Cross-references to related applications

[0001] This application claims priority to European patent application EP23202762.3 filed on October 10, 2023 and European patent application EP24162780.1 filed on March 11, 2024, the entirety of which is incorporated herein by reference. Technical Field

[0002] This invention relates to a magnetic levitation positioner assembly used in a photolithography apparatus. Background Technology

[0003] A lithography apparatus is a machine configured to apply a desired pattern to a substrate. For example, lithography apparatuses can be used in the manufacture of integrated circuits (ICs). For instance, a lithography apparatus may project a pattern (also commonly referred to as a “design layout” or “design”) from a patterning device (such as a mask) onto a layer of radiation-sensitive material (such as a photoresist) disposed on a substrate (such as a wafer).

[0004] For decades, as semiconductor manufacturing processes have continued to advance, the size of circuit elements has steadily decreased, while the number of functional components (such as transistors) in each device has steadily increased, following a trend commonly known as "Moore's Law." To keep pace with Moore's Law, the semiconductor industry is working on technologies that can produce increasingly smaller features. To project patterns onto a substrate, photolithography devices may use electromagnetic radiation. The wavelength of this radiation determines the minimum feature size that can be patterned on the substrate. Typical wavelengths currently used are 365 nm (i-line), 248 nm, 193 nm, and 13.5 nm.

[0005] A photolithography apparatus may include an irradiation system for providing a projection beam of radiation, and a support structure for supporting a patterning apparatus. The patterning apparatus may be used to impart a pattern on the cross-section of the projection beam. The apparatus may also include a projection system for projecting the patterned beam onto a target portion of a substrate.

[0006] To provide a desired pattern on a substrate, both the patterning apparatus and the substrate move relative to the projection system and relative to each other. For this purpose, linear and / or planar motor systems based on current-carrying coils and permanent magnets are used at room temperature or higher, as the coils generate heat. Linear and planar motor systems typically have a stator and a mover section; the mover section moves relative to the stator section in a controlled manner by adjusting the current flowing through the current-carrying coils.

[0007] For example, in some photolithography apparatuses, the surface of a long-stroke substrate positioner assembly is equipped with a checkerboard pattern of strong permanent magnets on the stator side. The substrate holder contains an electromagnet (e.g., in a Lorentz actuator) and is suspended above the stator. Replacing the permanent magnets on the stator with superconducting electromagnets can increase the magnetic field density and thus provide a significant increase in throughput. However, achieving high field density superconducting coils requires cryogenic cooling.

[0008] Various attempts have been made to realize a positioner with a superconducting electromagnet stage. For example, US2021 / 0223706A1 discloses a cryostat design with a superconducting coil suitable for photolithography. Here, the first stage of the cryostat is directly attached to an 80K spacer plate and the second stage of the cryostat is attached to an inner plate at <30K, on ​​which the superconducting coil is mounted. In this design, the cryostat serves as a heat sink for components at both temperature levels. The cold end of the cryostat has point connections to the cold surfaces (i.e., the spacer plate and the inner plate).

[0009] However, the inventors have discovered that in US2021 / 0223706A1, the cooling capacity of the cryocooler is limited by the number of point connections formed on the cold surface of the cryocooler, as well as the thermal conductivity of these connections and the heat generated / absorbed. Due to the heat generated near the superconducting coil at the top of the inner plate, and given that the average size of the inner plate can be greater than 1 meter, the temperature distribution of the superconducting coil can vary considerably even if the cryocooler is centrally located. As the inventors have found, if the temperature variation is large enough, it may potentially impair the performance of the positioner. Specifically, variations in ambient temperature can produce undesirable changes in the electromagnetic properties of the superconducting coil.

[0010] Furthermore, the inventors discovered that in US2021 / 0223706A1, the inner plate on which the superconducting coil is mounted has a limited heat capacity. When the inner plate is at a low temperature, the heat capacity further decreases. Therefore, when the superconducting coil generates excess heat, the inner plate has almost no ability to absorb the excess heat, leading to an overall temperature increase. Summary of the Invention

[0011] Therefore, the object of the present invention is to provide a cryogenic positioner with improved temperature distribution.

[0012] Another object of the present invention is to provide a cryogenic positioner that efficiently utilizes cooling power.

[0013] Another objective of this invention is to improve the temperature stability of the cryogenic positioner.

[0014] According to one aspect of the present invention, a component for use in a photolithography apparatus is disclosed, the component comprising: a thermal conditioning plate; a plurality of superconducting coils for magnetically levitizing and linearly displacing a stage thereon, wherein the plurality of superconducting coils are in thermal contact with the thermal conditioning plate; wherein: the thermal conditioning plate includes a first internal channel for containing a first refrigerant and a second internal channel for containing a second refrigerant; and the first internal channel and the second internal channel are thermally coupled to each other and fluidly isolated from each other, thereby achieving heat transfer between the first refrigerant and the second refrigerant while fluidly isolating the first refrigerant from the second refrigerant. Attached Figure Description

[0015] Embodiments of the present invention will now be described by way of example only with reference to the illustrative accompanying drawings, wherein corresponding reference numerals denote corresponding parts:

[0016] Figure 1 shows a photolithography apparatus according to an embodiment of the present invention.

[0017] Figure 2 shows a locator assembly according to an embodiment of the present invention.

[0018] Figure 3 shows a heat regulation plate according to an embodiment of the present invention.

[0019] Figure 4 shows a heat regulation plate according to an embodiment of the present invention.

[0020] Figures 5A and 5B illustrate the arrangement of the second internal passage according to an embodiment of the present invention.

[0021] Figure 6 shows a heat regulation plate according to an embodiment of the present invention.

[0022] Figure 7 shows a heat regulation plate according to an embodiment of the present invention.

[0023] Figure 8 shows a heat regulation plate according to an embodiment of the present invention.

[0024] Figure 9 shows a superconducting coil embedded in the inner surface of the first internal channel as shown in Figure 8.

[0025] Figure 10 shows a cross-section of a flexible catheter according to an embodiment of the present invention.

[0026] Figure 11 is a flowchart illustrating the operation sequence according to an embodiment of the present invention.

[0027] Figure 12 shows a locator assembly according to an embodiment of the present invention.

[0028] Figure 13 illustrates a locator assembly according to an embodiment of the present invention.

[0029] Features shown in the accompanying drawings are not necessarily drawn to scale, and the dimensions and / or arrangements depicted are not limiting. It should be understood that the drawings include optional features that may not be essential to the invention. Furthermore, not all features of the apparatus are shown in each drawing, and the drawings may only show some components relevant to describing particular features. Detailed Implementation

[0030] In the current document, the terms “radiation” and “beam” are used to cover all types of electromagnetic radiation, including ultraviolet radiation (e.g., wavelengths of 436 nm, 405 nm, 365 nm, 248 nm, 193 nm, 157 nm, 126 nm, or 13.5 nm).

[0031] As used herein, the terms “mask,” “mask,” or “patterning apparatus” are interpreted broadly to refer to a general patterning apparatus that can be used to impart a patterned cross-section to an incident radiation beam, corresponding to a pattern to be created on a target portion of a substrate. The term “optical valve” may also be used in this context. Examples of other such patterning apparatuses, besides classic masks (transmissive or reflective, binary, phase-shifting, hybrid, etc.), include programmable mirror arrays and programmable LCD arrays.

[0032] Figure 1 schematically illustrates a lithography apparatus LA. The lithography apparatus LA includes: an irradiation system (also called an irradiator) IL configured to modulate a radiation beam B (e.g., EUV radiation or DUV radiation); a mask support (e.g., a mask stage) MT configured to support a patterning apparatus (e.g., a mask) MA and connected to a first positioner PM configured to precisely position the patterning apparatus MA according to specific parameters; a substrate support (e.g., a substrate stage or substrate holder) WT configured to hold a substrate (e.g., a wafer coated with resist) W and connected to a second positioner PW configured to precisely position the substrate support according to specific parameters; and a projection system (e.g., a refractive projection lens system or a reflective optical system) PS configured to project a pattern imparted by the radiation beam B by the patterning apparatus MA onto a target portion C (e.g., including one or more dies) of the substrate W.

[0033] In operation, the irradiation system IL receives a radiation beam from the radiation source SO, for example via the beam delivery system BD. The irradiation 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 guiding, shaping, and / or controlling the radiation. The irradiator IL may be used to adjust the radiation beam B to have a desired spatial and angular intensity distribution in the cross-section of the plane in which the patterning device MA is located.

[0034] The term "projection system" (PS) as used herein should be interpreted broadly to encompass multiple types of projection systems, including refractive, reflective, catadioptric, variable, magnetic, electromagnetic, and / or electrostatic optical systems, or any combination thereof, adapted to the type of exposure radiation used and / or other factors such as immersion or vacuum environments. Any term used herein, "projection lens," may be considered equivalent to the more general term "projection system" (PS).

[0035] A lithography apparatus LA can be of the type in which a portion of the substrate is covered by a liquid (such as water) with a relatively high refractive index, such that it fills the space between the projection system PS and the substrate W—this is also known as immersion lithography. More information on immersion technology can be found in US6952253, which is incorporated herein by reference.

[0036] The lithography apparatus LA may also be of the type with two or more substrate supports WT (also known as "dual stage"). In such a "multi-stage" machine, the substrate supports WT may be used in parallel, and / or subsequent exposure preparation steps may be performed on a substrate W located on one of the substrate supports WT, while another substrate W located on the other substrate support WT is used to expose a pattern on that other substrate W.

[0037] In addition to the substrate support WT, the lithography apparatus LA may include a measurement stage. This measurement stage is arranged to hold sensors and / or cleaning equipment. The sensors may be arranged to measure characteristics of the projection system PS or the radiation beam B. The measurement stage may hold multiple sensors. The cleaning equipment may be arranged to clean a part of the lithography apparatus, such as a part of the projection system PS or a system providing immersion solution. The measurement stage may move below the projection system PS as the substrate support WT moves away from the projection system PS.

[0038] In operation, a radiation beam B is incident on a patterning apparatus MA (e.g., a mask) held on a mask support MT and patterned by a pattern (design layout) present on the patterning apparatus MA. After passing through the mask MA, the radiation beam B passes through a projection system PS, which focuses the beam onto a target portion C of the substrate W. The substrate support WT can be precisely moved, for example, to position different target portions C in a focused and aligned position along the path of the radiation beam B, using a second locator PW and a position measurement system PMS. Similarly, a first locator PM and possibly another position sensor (not explicitly shown in Figure 1) may be used for precise positioning of the patterning apparatus MA corresponding to the path of the radiation beam B. The patterning apparatus MA and the substrate W can be aligned with substrate alignment marks P1 and P2 using mask alignment marks M1 and M2. Although the illustrated substrate alignment marks P1 and P2 occupy dedicated target portions C, they may also be located in the space between target portions C. When substrate alignment marks P1 and P2 are located between target portions C, they are referred to as scribing alignment marks.

[0039] To illustrate this invention, a Cartesian coordinate system is used. A Cartesian coordinate system has three axes: the x-axis, the y-axis, and the z-axis. Any one of these axes is orthogonal to the other two. A rotation about the x-axis is called an Rx rotation. A rotation about the y-axis is called an Ry rotation. A rotation about the z-axis is called an Rz rotation. The x-axis and y-axis define the horizontal plane, while the z-axis is vertical. The Cartesian coordinate system does not limit the invention and is only used for illustration. Alternatively, another coordinate system (e.g., a cylindrical coordinate system) may be used to illustrate the invention. The orientation of the Cartesian coordinate system may be different, for example, giving the z-axis a component along the horizontal plane.

[0040] As described above, in order to provide a desired pattern to the substrate W, both the patterning apparatus MA and the substrate W move relative to the projection system PS and relative to each other. For this purpose, attempts have been made to implement a positioner with a superconducting electromagnet stage. For example, a cryostat design with a superconducting coil suitable for photolithography is disclosed in US2021 / 0223706A1, which is incorporated herein by reference. Here, the first stage of the cryostat is directly attached to the spacer plate at 80 K, and the second stage of the cryostat is attached to an inner plate at below 30 K, on ​​which the superconducting coil is mounted. In this design, the cryostat acts as a heat sink for the component at both temperature levels. The cold end of the cryostat is point-connected to the cold surfaces (i.e., the spacer plate and the inner plate).

[0041] However, as the inventors have discovered, in US2021 / 0223706A1, the cooling capacity of the cryocooler is limited by the number of point connections formed on the cold surface of the cryocooler, as well as the thermal conductivity between these connections and the heat generated / absorbed. Due to the heat generated near the superconducting coil on the top of the inner plate, and given that the average size of the inner plate is greater than one meter, the temperature distribution of the superconducting coil can vary considerably even if the cryocooler is located in the center. As the inventors have discovered, if the temperature variation is large enough, it can potentially impair the performance of the positioner. Specifically, variations in spatial temperature can produce undesirable changes in the electromagnetic properties of the superconducting coil.

[0042] To compensate for temperature variations, a more powerful cryogenic cooler might be used to maintain the hottest coil at the target temperature, but this results in a significant increase in the required cooling power. Alternatively, the number of connections between the cryogenic cooler and the cold surface could be increased, for example, by using multiple cryogenic coolers. However, this is problematic because the positioner experiences sharp accelerations during operation (e.g., greater than 10 ms on the stator side). -2 Furthermore, the cryogenic cooler must move with the positioner, and increasing the number of connections increases the total mass of the positioner, leading to mechanical difficulties. Specifically, such acceleration forces can be detrimental to the mechanical connection between the long, thin cryogenic cooler and the relatively rigid positioner. Another difficulty associated with increasing the number of connections is space constraints. Therefore, these design modifications each have their own drawbacks.

[0043] Figure 2 illustrates a positioner assembly 1 according to the present invention. Positioner assembly 1 includes a thermal adjustment plate 2 and a plurality of superconducting coils 5. The plurality of superconducting coils 5 are used to magnetically levitate and linearly displace the stage thereon. Positioner assembly 1 and stage 9 can be any positioner and stage within a photolithography apparatus LA. For example, stage 9 could be a mask support MT for a patterning apparatus MA, and positioner assembly 1 could be part of a first positioner PM. Alternatively or additionally, stage 9 could be a substrate support WT, and positioner assembly 1 could be a second positioner PW.

[0044] As shown in Figure 3, the heat regulating plate 2 may include a first internal channel 22 and a second internal channel 23. The first internal channel 22 may be used to contain a first refrigerant, and the second internal channel 23 may be used to contain a second refrigerant. The first and second refrigerants may be different substances from each other. A plurality of superconducting coils 5 may be in thermal contact with the heat regulating plate 2. For example, the superconducting coils 5 may be in direct contact with a portion of the heat regulating plate 2. In the arrangement shown in Figure 3, the superconducting coils 5 are disposed on the outer surface 21 of the heat regulating plate 2. However, as will be described later with reference to Figures 7 through 9, the superconducting coils 5 may instead be disposed within the heat regulating plate 2.

[0045] The first internal channel 22 and the second internal channel 23 may be thermally coupled to each other, thus heat may be transferred between the first refrigerant and the second refrigerant contained within the respective internal channels. Furthermore, the first internal channel 22 and the second internal channel 23 may be fluidly isolated from each other, thus the first refrigerant and the second refrigerant contained within the respective internal channels may be fluidly isolated from each other. This may prevent the first refrigerant from mixing with the second refrigerant. Refrigerant mixing may be undesirable because it can complicate refrigerant recovery / reuse. Specifically, some refrigerants may undergo chemical reactions upon mixing. For example, nitrogen may react with hydrogen to form ammonia.

[0046] Furthermore, as shown in Figure 3, the first internal channel 22 may extend substantially concurrently with the plurality of superconducting coils 5. That is, the first internal channel 22 may have a lateral extent similar to or substantially the same as that of the plurality of superconducting coils 5. Similarly, the second internal channel 23 may extend substantially concurrently with the plurality of superconducting coils 5. This may contribute to improving the uniformity of thermal regulation (e.g., providing cooling to the superconducting coils 5).

[0047] Because the refrigerant flows within the first internal channel 22 and the second internal channel 23 within the thermal conditioning plate 2, multiple superconducting coils 5 can be thermally regulated (e.g., cooled) more uniformly compared to providing cooling at a limited number of connection points in the cryogenic cooler. In other words, the temperature distribution of the superconducting coils 5 can become more uniform. This, in turn, may lead to more uniform performance of the superconducting coils 5.

[0048] Furthermore, since cooling is provided via the first internal channel 22 and the second internal channel 23 instead of multiple connection points of multiple cryogenic coolers, the positioner assembly 1 can be more compact, which may be desirable given the limited space around it. Specifically, the total mass of the moving parts of the positioner assembly 1 can be reduced. This can reduce the amount of vibration generated during LA operation of the lithography apparatus.

[0049] Furthermore, since the refrigerant flows within the heat regulation plate 2, the refrigerant within the heat regulation plate 2 at a given moment may provide a buffer against quench events.

[0050] A quenching event refers to the transition of an electromagnet from a superconducting state to a non-superconducting state, resulting in an increase in resistance. Since the electromagnet may initially be only slightly non-superconducting, the increase in resistance may be small. However, as current continues to flow through the coil, the increase in resistance may generate a certain amount of heat (through Joule heating). The lack of a sufficient heat sink or heat transfer path causes the temperature of the electromagnet coil to rise further, and the resistance increases accordingly in a self-reinforcing, runaway manner. Specifically, quenching may typically begin at a localized location within an originally superconducting electromagnet and may propagate as a heat wave to adjacent regions of the electromagnet, causing more areas of the electromagnet to become non-superconducting. This can thus trigger a chain reaction and potentially lead to the complete loss of superconductivity of the entire electromagnet. Therefore, quenching events are undesirable and may also lead to irreversible weakening of the material of the thermal conditioning plate 2.

[0051] Adding a heat sink can reduce the probability of quench events. For example, a passive heat sink may be provided. For example, multiple superconducting coils 5 may be brought into thermal contact with a thermal mass (such as a heat-conducting plate (e.g., a copper or aluminum plate)) to provide a passive heat sink. For example, the material of the thermal conditioning plate 2 may provide some passive heat sink capability.

[0052] However, active heat absorption capacity may be desirable. As mentioned above, the refrigerant within the thermal regulating plate 2 at a given time may provide additional heat absorption capacity. Specifically, the presence of refrigerant within the thermal regulating plate 2 may provide additional heat absorption capacity because the material of the thermal regulating plate 2 may have a reduced heat capacity at low temperatures (e.g., in the event of an unplanned shutdown). More specifically, the refrigerant may maintain the thermal regulating plate 2 at a low temperature while absorbing a significant amount of heat from the superconducting coil 5, particularly through latent heat of fusion and / or latent heat of vaporization. Other active technologies may be employed additionally, such as bleed resistors and quench return heaters.

[0053] As shown in Figure 3, the first internal channel 22 may include a plenum. For example, this plenum may be a continuous spatial volume within the heat-regulating plate 2 that substantially spans the entire lateral extent of the heat-regulating plate 2. Alternatively, the plenum may span a major portion of the lateral extent of the heat-regulating plate 2. For example, the plenum may have approximately one-half, one-third, one-quarter, one-fifth, one-sixth, or one-seventh of the lateral area of ​​the heat-regulating plate 2. The first internal channel 22 may include multiple such plenums. By constructing the first internal channel 22 as a plenum, the first internal channel 22 may be able to hold a large volume of first refrigerant, which may in turn provide a larger heat sink.

[0054] Similarly, as shown in Figure 3, the second internal passage 23 may also include a gas chamber. By configuring the second internal passage 23 as a gas chamber, the second internal passage 23 may be able to hold a large volume of second refrigerant.

[0055] The positions of the first internal channel 22 and the second internal channel 23 relative to the superconducting coil 5 may be positioned differently. For example, as shown in FIG3, the second internal channel 23 may be positioned between the multiple superconducting coils 5 and the first internal channel 22. For example, the second refrigerant (flowing within the second internal channel 23) may primarily serve to dissipate heat from the multiple superconducting coils 5 and their immediate vicinity during normal operation, and the first refrigerant (contained within the first internal channel 22) may primarily serve as an additional heat sink in the event of unplanned excess heat generation. That is, if the temperature of the superconducting coil 5 begins to rise and the rate of heat generation exceeds the rate of heat dissipation provided by the second refrigerant within the second internal channel 23, the first refrigerant within the first internal channel 22 may provide additional heat absorption capacity. This may help to slow the temperature rise and may prevent quench events from occurring. The advantage of placing the second internal channel 23 closer to the superconducting coil 5 may be to enhance heat transfer between the superconducting coil 5 and the second refrigerant within the second internal channel 23.

[0056] As described above, the second internal channel 23 may include an air chamber. Additionally or alternatively, as shown in FIG4, the second internal channel 23 may include a channel network. As shown, this channel network may include multiple channels 231 passing through the cross-section of the heat-regulating plate 2. The channels 231 may be elongated passages. Although FIG4 shows the channels 231 as having a circular cross-section, they may have any suitable cross-sectional shape.

[0057] The advantage associated with the flow of the second refrigerant in the channel network of the second internal channel 23 is the potential reduction of sloshing. That is, for the gas chamber of the second internal channel 23 as shown in FIG3, the second refrigerant may slosh around within the gas chamber during operation of the lithography apparatus LA, potentially generating greater mechanical vibrations. More specifically, when a closed volume containing fluid (e.g., a gas chamber) undergoes acceleration, the fluid itself may also be accelerated. This non-flow-induced acceleration (i.e., sloshing) acts as a sound source and generates pressure waves within the closed volume. These pressure waves may subsequently propagate through the fluid lines (at the speed of sound) and may introduce dynamic pressures that lead to dynamic deformation (i.e., vibration). In contrast, by employing the channel network shown in FIG4, any movement of the second refrigerant is confined within the channels 231 of the second internal channel 23, which in turn limits mechanical vibrations.

[0058] The thermal regulating plate 2 may be constructed in various forms. For example, the thermal regulating plate 2 may include a thermally conductive material. Examples of thermally conductive materials include aluminum, copper, aluminum alloys, and copper alloys. The thermal regulating plate 2 may include a high-stiffness material, such as stainless steel. High stiffness may be desirable because it may allow the thermal regulating plate 2 to withstand sharp acceleration forces during operation of the lithography apparatus LA. High stiffness may be achieved through material selection and / or structural design. Depending on the manufacturing method, the thermal regulating plate 2 may be constructed from a single material or may be constructed from multiple materials. Specifically, the thermal regulating plate 2 may be constructed from multiple materials with different thermal conductivity.

[0059] For example, the heat regulating plate 2 may be formed by casting, in which case the first internal channel 22 and the second internal channel 23 may be formed directly during the casting process. Alternatively, the heat regulating plate 2 may initially be manufactured as three plates, with the first internal channel 22 and the second internal channel 23 machined into one, two, or all three plates, which may then be joined together using, for example, vacuum brazing or other suitable methods to seal the first internal channel 22 and the second internal channel 23. Alternatively or additionally, in embodiments containing a network of channels in the second internal channel 23, the heat regulating plate 2 may be formed by fitting forged pipes of the desired shape into corresponding machined passages on the surface of the heat regulating plate 2. The forged pipes may be tightly fitted within the heat regulating plate 2, such that the materials of the forged pipes and the heat regulating plate 2 form good thermal contact. As another alternative, in embodiments containing a network of channels in the second internal channel 23, the heat regulating plate 2 may be formed by drilling parallel holes in a solid plate and sealing the surface holes with plugs. As an alternative, in embodiments comprising a second internal channel 23 containing a network of channels, the heat regulating plate 2 may be formed by forging the conduit into the desired shape of the second internal channel 23 and by casting the heat regulating plate 2 around the forged conduit. Specifically, in this manufacturing method, the conduit may be made of stainless steel, which may be cast from aluminum (or an aluminum alloy) with a lower melting point to form the heat regulating plate 2. It should be understood that these manufacturing methods are merely non-limiting examples; other suitable manufacturing methods may be used to form the heat regulating plate 2.

[0060] Another suitable material for manufacturing the heat regulating plate 2 is ceramic. In addition to its high rigidity, using ceramic as the material for the heat regulating plate 2 may be advantageous because it does not generate eddy current losses.

[0061] In embodiments incorporating a second internal channel 23 with a channel network, the internal channels may have different geometries or topologies. Typically, the channel network may comprise one or more elongated channels covering a range within the thermal regulating plate 2. Figures 5A and 5B illustrate two non-limiting examples of channel networks. As shown in Figure 5A, the channel network may comprise channels 231 connected alternately to form a serpentine pattern. In one example, the channel network may be a single, continuous channel without branches. Alternatively, the channel network may have branches. For example, Figure 5B illustrates a channel network comprising a series of parallel-connected channels 231. In this arrangement, a flow restrictor 223 may be positioned at or near the inlet of each individual parallel channel 231, thereby calibrating the channel network to provide uniform refrigerant flow across the parallel channels. Furthermore, in the arrangement of Figure 5B, a supply line 64 and a return line 65 for the second refrigerant may be positioned at opposite ends of the series of parallel channels, which may help balance the flow between the parallel channels.

[0062] The channel network can be formed into any other suitable geometry. For example, the channel network may have a tortuous geometry. The elongated shape of the channel network may help reduce sloshing. Furthermore, the presence of bends in the channel network may also help reduce sloshing. Specifically, sloshing may be reduced by reducing the number and / or length of straight channels.

[0063] It should be understood that the serpentine structure of Figure 5A and the parallel channel arrangement of Figure 5B may be combined in a single channel network of the second internal channel 23. It should also be understood that the channel network may include multiple segments, each segment may have the same or different geometry, and the segments may be interconnected or isolated from each other. Furthermore, different segments of the second internal channel 23 may be arranged laterally within the heat-regulating plate 2.

[0064] As described above, as shown in Figures 3 and 4, the first internal channel 22 may include an air chamber. Additionally or alternatively, the first internal channel 22 may include a channel network similar to the second internal channel 23 described above. As shown in Figure 6, the channel network of the first internal channel 22 may include a series of channels 221, which may be connected in various ways to form a channel network as shown in Figures 5A (serpentine) and 5B (parallel connected channels) or other forms described above. The advantage of constructing the first internal channel 22 as a channel network is that cooling can be more evenly distributed to the heat exchange plate 2.

[0065] In the examples shown in Figures 3, 5A to 5B, and 6, multiple superconducting coils 5 are disposed on the outer surface 21 of the thermal conditioning plate 2. Referring to Figure 2, this may have the advantage that the superconducting coils 5 can be relatively close to the stage 9, which may result in a stronger magnetic force between the superconducting coils 5 and the stage 9.

[0066] Alternatively, as shown in Figure 7, multiple superconducting coils 5 may be disposed within the first internal channel 22. As a result, the multiple superconducting coils 5 may be immersed in the first refrigerant. This may improve the heat transfer efficiency between the superconducting coils 5 and the first refrigerant contained within the first internal channel 22.

[0067] As shown in Figure 7, the first internal channel 22 may be located between the second internal channel 23 and the outer surface 21 facing the stage 9 (not shown in Figure 7). This may allow the superconducting coil 5 contained within the first internal channel 22 to be closer to the stage 9.

[0068] As shown in Figure 7, the first internal channel 22 may include an air chamber. The first internal channel 22 may therefore have two transverse inner surfaces 228, 229. The first inner surface 228 may be farther from the stage 9 than the second inner surface 229, which is closer to the stage 9.

[0069] In the example shown in Figure 7, multiple superconducting coils 5 are disposed on the first inner surface 228. This may be advantageous because the thermal conditioning plate 2 may be constructed as three plates clamped together, and the formation of the first inner channel 22 and the second inner channel 23, as well as the fixation of the multiple superconducting coils 5, may both be performed on the intermediate plate. Alternatively, the multiple superconducting coils 5 may be disposed on the second inner surface 229. This may have the advantage of bringing the superconducting coils 5 closer to the stage 9.

[0070] As a further improvement, as shown in Figure 8, multiple superconducting coils 5 may be embedded in the first inner surface 228. That is, a recess 225 may be formed in the first inner surface 228, and multiple superconducting coils 5 may be inserted into the recess. This arrangement may improve the stability of the multiple superconducting coils 5 within the first internal channel 22.

[0071] Figure 9 shows a three-dimensional view of how multiple superconducting coils 5 may be assembled in recesses 225 formed in the first inner surface 228. As shown, the multiple superconducting coils 5 may be arranged in a checkerboard pattern. As shown, the multiple superconducting coils 5 may have alternating polarities (indicated by "N" and "S"). That is, each "south" coil may be surrounded by four "north" coils, and each "north" coil may be surrounded by four "south" coils. As shown, the recesses 225 may slightly overlap each other, such that the material of the thermal adjustment plate 2 may form incomplete walls separating a "north" coil from an adjacent "south" coil. Alternatively, the recesses 225 may not overlap, such that each coil may be surrounded by a complete wall.

[0072] It should be understood that the recess 225 described with reference to Figure 9 above may alternatively be formed in the second inner surface 229, such that the superconducting coil 5 may be embedded in the second inner surface 229.

[0073] Referring to Figure 2, a control system 71 may be provided to control the flow of the first refrigerant and the second refrigerant within the first internal channel 22 and the second internal channel 23, respectively. Furthermore, the second refrigerant may have a lower freezing point than the first refrigerant. The freezing points of the first and second refrigerants may be defined at any operating pressure employed according to a specific embodiment of the invention. For example, the freezing points of the first and second refrigerants may be defined at atmospheric pressure. Generally, at pressures between absolute vacuum and atmospheric pressure, the freezing point of a refrigerant does not change significantly with pressure.

[0074] Using the heat-regulating plate 2 shown in Figures 3, 4, and any of Figures 6 through 8, the control system 71 may allow the second refrigerant to flow in the second internal channel 23, thereby cooling the heat-regulating plate 2 and the first refrigerant in the first internal channel 22. Specifically, the control system 71 may allow the second refrigerant to flow in the second internal channel 23, thereby cooling the heat-regulating plate 2 to a temperature below and / or maintaining that temperature of the first refrigerant. In other words, the second refrigerant may cause the first refrigerant to freeze. This may be feasible because the second refrigerant may remain in a liquid state while the first refrigerant has frozen.

[0075] Freezing the first refrigerant may be advantageous because it increases its heat absorption capacity. Specifically, the frozen first refrigerant may absorb a large amount of heat in the form of heat of fusion, while maintaining the heat regulating plate 2 at the melting point of the first refrigerant until substantially all of the first refrigerant contained within the first internal channel 22 has melted. Due to the large heat of fusion, the frozen first refrigerant may provide a much greater heat absorption capacity than the equivalent volume of heat regulating plate 2 material. The heat absorption capacity provided by the solid first refrigerant within the first internal channel 22 may also maintain the heat regulating plate 2 at a low temperature during short-term interruptions (e.g., up to about 10 minutes) caused, for example, by a power outage.

[0076] Another advantage of freezing the first refrigerant is that it eliminates sloshing within the first internal channel 22. As mentioned above, reducing sloshing may help reduce mechanical vibration of the positioner assembly 1 during operation.

[0077] As another advantage, in the examples shown in Figures 7 and 8, freezing the first refrigerant within the first internal channel 22 may help to secure the multiple superconducting coils 5 within the first internal channel 22. This is because the thermal expansion rate of a solid refrigerant is typically lower than that of the materials used to construct the heat-regulating plate 2 and the multiple superconducting coils 5 (e.g., steel, aluminum, and copper). Therefore, as the first refrigerant solidifies and the overall temperature of the heat-regulating plate 2 decreases, the shrinkage of the material of the heat-regulating plate 2 and the multiple superconducting coils 5 will be greater than that of the solid first refrigerant. As a result, the solid first refrigerant may exert a clamping force on the multiple superconducting coils 5, which may firmly hold the multiple superconducting coils 5 in their position within the first internal channel 22.

[0078] As shown in Figures 8 and 9, the recess 225 may be slightly larger than the plurality of superconducting coils 5, thus leaving a small gap between each superconducting coil 5 and the vertical wall of the recess 225. During operation, these gaps may be filled with a first refrigerant initially in a liquid state. As the first refrigerant is cooled by a second refrigerant to below its freezing point, the first refrigerant in the gaps will solidify together with the bulk portion of the first refrigerant within the first internal channel 22. Due to the aforementioned difference in thermal expansion rates, the solidified first refrigerant within the gaps between the plurality of superconducting coils 5 and the vertical wall of the recess 225 may exert an additional lateral clamping force on the plurality of superconducting coils 5. This may enhance the stability of the plurality of superconducting coils 5 within the first internal channel 22.

[0079] Therefore, in some embodiments, during steady-state operation, the first refrigerant may remain solid within the first internal channel 22, its primary function likely being to provide additional heat sinking. Simultaneously, the continuous flow of the second refrigerant within the second internal channel 23 may dissipate any heat generated by the multiple superconducting coils 5 and maintain the first refrigerant in a solid state. If the temperature of the thermal regulating plate 2 rises to the melting point of the first refrigerant, the solid first refrigerant, due to its greater heat of fusion, may provide a larger heat sink. This could effectively prevent quench events.

[0080] It may be necessary to periodically shut down the lithography apparatus (LA) and allow the thermal regulating plate 2 to heat up to room temperature. To allow the thermal regulating plate 2 to cool down, the control system 71 may allow the first refrigerant to flow through the first internal channel 22 to cool the thermal regulating plate 2. Initially, when the temperature of the thermal regulating plate 2 is relatively high, the first refrigerant may boil as it flows through the first internal channel 22. The control system 71 may continue to allow the first refrigerant to flow through the first internal channel 22 to cool the thermal regulating plate 2 until it reaches a temperature below the boiling point of the first refrigerant. At this point, the first refrigerant may flow through the first internal channel 22 without boiling. The control system 71 may continue to allow the first refrigerant to flow through the first internal channel 22 to further cool the thermal regulating plate 2 to near the freezing point of the first refrigerant. Specifically, the control system 71 may stop the flow of the first refrigerant in the first internal channel 22 before the temperature of the thermal regulating plate 2 reaches the freezing point of the first refrigerant. Therefore, the flow of the first refrigerant may stop before solid particles begin to form. That is, the flow of the first refrigerant may stop before a slurry containing a mixture of liquid first refrigerant and solid particles of first refrigerant begins to form.

[0081] After initially allowing the first refrigerant to flow in the first internal channel 22 and then stopping the flow of the first refrigerant, the control system 71 may switch to allowing the second refrigerant to flow in the second internal channel 23. As described above, the flow of the second refrigerant may further cool the thermal regulating plate 2 and the first refrigerant in the first internal channel 22. As described above, the control system 71 may continue to allow the second refrigerant to flow in the second internal channel 23 until the first refrigerant freezes in the first internal channel 22.

[0082] More specifically, referring to Figure 11, the cooling process of the heat regulating plate 2 may begin in step 81 from a higher temperature (e.g., room temperature). In step 82, the control system 71 may allow a first refrigerant to flow in the first internal channel 22 to cool the heat regulating plate 2. In step 83, the control system 71 may continuously monitor the temperature of the heat regulating plate 2. If the temperature of the heat regulating plate 2 is higher than the boiling point of the first refrigerant, the control system 71 may return to step 82 and continue the flow of the first refrigerant in the first internal channel 22. On the other hand, if the temperature of the heat regulating plate 2 has reached a temperature lower than the boiling point of the first refrigerant, the control system 71 may proceed to step 84 and stop the flow of the first refrigerant. Subsequently, the control system 71 may switch in step 85 to allow a second refrigerant to flow in the second internal channel 23, thereby further cooling the heat regulating plate 2 and the first refrigerant.

[0083] Different refrigerants can be used to thermally regulate (e.g., cool) the heat regulation plate 2. Table 1 below lists examples of suitable refrigerants and some of their associated thermodynamic properties. Table 1

[0084] As mentioned above, the freezing point of the second refrigerant may be lower than that of the first refrigerant. The first and second refrigerants may be selected from Table 1 above based on this principle. For example, the first refrigerant may be nitrogen, and the second refrigerant may be hydrogen. When using hydrogen as the second refrigerant, multiple superconducting coils 5 may be cooled to an operating temperature of approximately 20.3 K. Any other suitable combination of the two refrigerants may be used.

[0085] In a non-limiting embodiment of the arrangement shown in Figures 7 and 8, the first internal channel 22 is sized to allow a first refrigerant layer 10 mm thick (excluding the thickness of the plurality of superconducting coils 5). In this embodiment, the first refrigerant is nitrogen, and the plurality of superconducting coils 5 are made of copper. At approximately 20 K, the specific heat capacity of solid nitrogen is approximately 60 times that of copper. In this embodiment, each superconducting coil 5 contains 80 grams of solid first refrigerant, which is approximately one-fifth the weight of each coil. In this embodiment, it has been found that using solid nitrogen can reduce the temperature rise to a few Kelvin, approximately one-twelfth of the temperature rise when the solid nitrogen is replaced with an equal volume of the material of the heat-regulating plate 2 (aluminum). This 12-fold factor also keeps the temperature fluctuation caused by AC losses within 0.01 K (reduced from approximately 0.1 K). Although the resistance is zero under steady-state conditions, AC losses still occur because alternating current and alternating magnetic fields can cause energy dissipation in the superconductor. Eddy currents can also exacerbate AC losses. For short-term power outages of up to approximately 10 minutes, solid nitrogen can halve the temperature rise to below 1K, allowing positioner assembly 1 to potentially resume operation immediately without recooling. For long-term outages of approximately 24 hours, solid nitrogen can reduce the temperature rise from approximately 50K to 30K and may roughly halve the recooling time to approximately 3 hours.

[0086] To achieve and maintain the thermal regulating plate 2 at a low temperature without requiring excessive cooling power, it may be advantageous to thermally isolate the thermal regulating plate 2 and the multiple superconducting coils 5 from the external environment. For example, as shown in Figure 2, the positioner assembly 1 may also include a vacuum chamber 4. The vacuum chamber 4 surrounds the thermal regulating plate 2 and the multiple superconducting coils 5.

[0087] A vacuum may be applied to the space within vacuum chamber 4. A vacuum pump (not shown) may be connected to the volume of space within vacuum chamber 4 for this purpose. The vacuum pump may also help prevent the buildup of solid deposits on cold surfaces. Specifically, when a surface reaches a low temperature (e.g., below 44 K), any molecules in contact with that cold surface (e.g., except for helium, neon, or hydrogen) will solidify and will no longer exist as free gases. This may, in turn, reduce the pressure within vacuum chamber 4, even without the assistance of a vacuum pump. However, allowing condensate to build up may be undesirable, as this could reduce thermal performance and / or create electrical short circuits (e.g., between the thermal regulating plate 2 and vacuum chamber 4). To avoid solid buildup, the vacuum pump may be used to remove molecules from vacuum chamber 4 before cooling.

[0088] Furthermore, since the molecules present in the vacuum chamber 4 may promote convective heat transfer, their presence may prolong the time required to cool the thermal regulating plate 2 to the target temperature. Therefore, by evacuating the vacuum chamber 4 before cooling, it is possible to reduce the time and energy required to cool the thermal regulating plate 2.

[0089] Although vacuum is an effective insulation method, other insulation methods may be used as alternatives.

[0090] Positioner assembly 1 may alternatively or additionally include a heat shield 3 to improve thermal insulation. As shown in Figure 2, the heat shield 3 may surround the thermal regulating plate 2 and multiple superconducting coils 5. In the presence of a vacuum chamber 4, the heat shield 3 may also be surrounded within the vacuum chamber 4.

[0091] Using this arrangement as a non-limiting example, the thermal conditioning plate 2 and the plurality of superconducting coils 5 may be maintained at about 44 K or lower, preferably 10 to 35 K, and more preferably 20 K or lower. The thermal shield 3 may be maintained at about 50 to 90 K. The vacuum chamber 4 may be maintained at room temperature, i.e., about 295 K. It should be understood that the vacuum applied in the vacuum chamber 4 does not need to be a perfect vacuum. For example, the pressure in the vacuum chamber 4 may be maintained at about 10 Pa or lower.

[0092] To further improve the insulation of the thermal regulating plate 2, the thermal shield 3 may include an internal network of channels 32 for allowing refrigerant to flow therethrough. This may further reduce the temperature inside the thermal shield 3, which could help ensure that the thermal regulating plate 2 and the multiple superconducting coils 5 can be maintained at the required low temperature. To further improve the insulation effect, where space permits, additional thermal shields similar to the thermal shield 3 may be provided.

[0093] As shown in Figure 2, the vacuum chamber 4 may include a through-section 43 through which refrigerant is supplied to the first internal channel 22 and the second internal channel 23 of the heat regulating plate 2. For example, as shown in Figure 2, a first refrigerant supply line 61 may be configured to pass through the through-section 43 and may be connected to the first internal channel 22 of the heat regulating plate 2. A second refrigerant supply line 64 may also be configured to pass through the through-section 43 and may be connected to the second internal channel 23 of the heat regulating plate 2. Refrigerant for the internal channel network 32 of the heat shield 3 may similarly be supplied through the through-section 43 of the vacuum chamber 4. More generally, any desired number of refrigerant supply sources may be configured to pass through the through-section 43 of the vacuum chamber 4. The existing arrangement may reduce the required number of through-sections compared to contacting multiple cryogenic coolers with the heat regulating plate 2 at multiple point connections (which would require a corresponding number of through-sections).

[0094] Furthermore, as shown in Figure 2, the positioner assembly 1 may include a flexible conduit 6 configured to pass through a through-port 43 of the vacuum chamber 4. Refrigerant may be supplied through the flexible conduit 6 to the first internal channel 22 and the second internal channel 23 of the thermal regulating plate 2 and / or the internal channel network 32 of the thermal shield 3. The flexibility of the flexible conduit 6 may help compensate for movement of the thermal regulating plate 2, the thermal shield 3, and / or the vacuum chamber 4 during operation of the lithography apparatus LA. The thermal regulating plate 2 may move by as much as 10 mm to 100 mm, for example, 50 mm. This may be caused by movement of the vacuum chamber 4 during scanning operations of the lithography apparatus LA. Alternatively or additionally, the thermal regulating plate 2 may move due to thermal shrinkage. Furthermore, to accommodate such movement, one or more of the thermal regulating plate 2, the thermal shield 3, and the vacuum chamber 4 may be flexibly suspended rather than rigidly fixed. For example, flexible mechanical supports (not shown) may mechanically connect the thermal regulating plate 2 and the vacuum chamber 4. These mechanical supports may be configured to pass through gap holes in the thermal shield 3. Vacuum chamber 4 may also be attached to the lithography apparatus LA in a similar manner using flexible mechanical supports. Typically, these mechanical supports are expected to have low thermal conductivity to reduce heat reaching the thermal conditioning plate 2 from the external environment. For example, these mechanical supports may comprise materials with low thermal conductivity. The mechanical supports may also have a small cross-sectional area.

[0095] In the simplest case, the refrigerant supplied to the first internal channel 22 and the second internal channel 23 may be discharged into the environment after passing through the first internal channel 22 and the second internal channel 23. However, this may cause refrigerant loss, so the refrigerant supplied to the first internal channel 22 and the second internal channel 23 may be recycled. For example, as shown in FIG2, in addition to the refrigerant supply lines 61 and 64 for the first and second refrigerants to flow to the first internal channel 22 and the second internal channel 23, the positioner assembly 1 may also include a first refrigerant return line 62 and a second refrigerant return line 65 through which the first and second refrigerants flow out of the first internal channel 22 and the second internal channel 23. As shown in FIG2, the refrigerant supply lines 61, 64 and the refrigerant return lines 62, 65 may all be arranged within the flexible conduit 6. That is, the refrigerant supply lines and return lines 61, 62, 64, and 65 may be configured to pass through the same through-section 43 of the vacuum chamber 4. Compared to the arrangement of passing the refrigerant supply lines and return lines 61, 62, 64, and 65 through separate flexible conduits and separate through-sections, the arrangement of passing the refrigerant supply lines and return lines 61, 62, 64, and 65 through the same flexible conduit 6 or the same through-section 43 may reduce the number of flexible conduits and through-sections required. This may further reduce the heat transferred from the external environment to the thermal regulating plate 2.

[0096] To provide electrical power to multiple superconducting coils 5, power supply leads 63 may be used. As shown in Figure 2, power supply leads 63 may also be disposed within a flexible conduit 6. Specifically, power supply leads 63 may be disposed within the same flexible conduit 6 as refrigerant supply lines 61, 64. Power supply leads 63 may typically need to carry a large current (e.g., 1kA to 5kA, or at least 2kA). Given the large current carried by power supply leads 63, cooling the power supply leads may be advantageous, thereby reducing resistance losses. For this purpose, power supply leads 63 may be surrounded by refrigerant. Specifically, power supply leads 63 may be surrounded by a second refrigerant supplied to the second internal channel 23 of the thermal conditioning plate 2. Since the second refrigerant will remain liquid, power supply leads 63 may be continuously cooled. Power supply leads 63 may be superconducting. Another advantage of using superconducting power supply leads 63 is that the diameter of power supply leads 63 can be reduced without increasing resistance losses.

[0097] More specifically, as shown in Figure 2, a power supply lead 63 may be disposed within the second refrigerant supply line 64 and / or the second refrigerant return line 65. Advantageously, as shown in Figure 10, one of the power supply leads 63 may be disposed within each of the second refrigerant supply line 64 and the second refrigerant return line 65. More specifically, as shown in Figure 10, one power supply lead 63 may be surrounded by the second refrigerant 640 in the second refrigerant supply line 64, and the other power supply lead 63 may be surrounded by the second refrigerant 650 in the second refrigerant return line 65. Instead of having two (or more) power leads 63 within a single refrigerant supply line 64 or refrigerant return line 65, the second refrigerant supply line 64 and / or the second refrigerant return line 65 can have a relatively smaller diameter, which may make them more flexible. This greater flexibility may allow the second refrigerant supply line 64 and the second refrigerant return line 65 to better compensate for movement of the thermal regulating plate 2, and / or the thermal shield 3, and / or the vacuum chamber 4. Furthermore, combining the power supply, refrigerant supply, and vacuum supply within the same flexible conduit 6 may improve compactness.

[0098] Because the flexible conduit 6 may have a certain length necessary to accommodate the movement of the thermal regulating plate 2, the thermal shield 3, and / or the vacuum chamber 4, the refrigerant may absorb heat from the external environment as it flows within the flexible conduit 6. To reduce the heat transferred from the external environment into the refrigerant within the flexible conduit 6, a vacuum may be applied to the space 60 between the refrigerant supply and return lines 61, 62, 64, 65 and the flexible conduit 6. In one arrangement as shown in Figure 2, this gap space 60 (i.e., the space between the refrigerant supply and return lines 61, 62, 64, 65 and the flexible conduit 6) may be in fluid communication with the internal volume of the vacuum chamber 4. This arrangement may use a common vacuum source (such as a vacuum pump) to apply a vacuum to the internal volume of the vacuum chamber 4 and the gap space 60 of the flexible conduit 6. Alternatively, the gap space 60 of the flexible conduit 6 and the internal volume of the vacuum chamber 4 may not be in fluid communication, and a vacuum may be applied separately.

[0099] To reuse the refrigerant, the positioner assembly 1 may include a refrigerant circulation unit 7, as shown in FIG2. The refrigerant circulation unit 7 may be configured to receive a first refrigerant and a second refrigerant from a first internal channel 22 and a second internal channel 23, cool the received refrigerant, and supply the cooled refrigerant to the first internal channel 22 and the second internal channel 23. For example, the first refrigerant received from the first internal channel 22 may be cooled by a first cryogenic cooler 73 before flowing back to the first internal channel 22. Similarly, the second refrigerant received from the second internal channel 23 may be cooled by a second cryogenic cooler 75 before flowing back to the second internal channel 23.

[0100] In addition, the control system 71 may be used to control the flow rate, pressure and / or temperature of the refrigerant supplied to the first internal passage 22 and the second internal passage 23.

[0101] For example, it may be desirable to keep the second refrigerant in a liquid state throughout the entire second internal channel 23 of the heat regulating plate 2. Therefore, the control system 71 may be configured to control one or more of the flow rate, pressure, and temperature of the second refrigerant supplied to the second internal channel 23, such that the temperature of the second refrigerant received from the second internal channel 23 is between its freezing point and boiling point. The control system 71 may also maintain the temperature of the second refrigerant below the freezing point of the first refrigerant. This may help to keep the first refrigerant in the first internal channel 22 in a solid state.

[0102] Furthermore, the control system 71 may be positioned close to the heat exchanger 2. In other words, the downstream sections 612 and 642 of the refrigerant supply lines 61 and 64 may be shorter than the upstream sections 611 and 641 of the supply lines 61 and 64. This may be advantageous because the heat absorbed by the refrigerant in the refrigerant supply lines 61 and 64 may be difficult to predict. By positioning the control system 71 relatively close to the operating location (i.e., close to the heat exchanger 2), the actual refrigerant state supplied to the first internal channel 22 and the second internal channel 23 may be more precisely controlled.

[0103] Positioner assembly 1 may also include a first buffer tank 72 and a second buffer tank 74, which may be configured to hold a certain volume of first refrigerant and second refrigerant, respectively. A first cryogenic cooler 73 and a second cryogenic cooler 75 may use corresponding cooling circuits 731, 751 to cool the respective refrigerants. As shown in FIG2, each of the cooling circuits 731, 751 may include heat exchangers 721, 741 for cooling the refrigerant in the buffer tanks 72, 74. In an embodiment, the working fluid within the cooling circuits 731, 751 may be helium. Buffer tanks 72, 74 may provide thermal buffering because a relatively large amount of refrigerant can be maintained at a desired temperature during planned or unplanned downtime (e.g., during maintenance or a brief power outage). Furthermore, the second buffer tank 74 may be disposed within the first buffer tank 72, such that the first refrigerant may act as a thermal shield for the second refrigerant within the second buffer tank 74. Additionally, the second buffer tank 74 may be a double-walled vacuum-insulated type, thereby providing a vacuum shield between the first and second refrigerants. Similarly, the first buffer tank 72 may also be a double-walled vacuum insulated type, thus providing a vacuum shield between the first refrigerant and the external environment (typically at room temperature). When the shutdown ends, the cooling process of the system may be shortened compared to an arrangement without buffer tanks 72, 74.

[0104] Although the first buffer tank 72 and the first cryogenic cooler 73 are shown as separate components in Figure 2, it should be understood that these components may be housed within a single unit. Similarly, the second buffer tank 74 and the second cryogenic cooler 75 may be housed within a single unit. For example, the first cryogenic cooler 73 and the second cryogenic cooler 75 may be two temperature stages of a combined cryogenic cooler, whereby the first refrigerant may be cooled by the first stage of the combined cryogenic cooler, and the second refrigerant may be cooled by the second stage. It should be further understood that any cryogenic cooler suitable for supplying refrigerant to the thermal conditioning plate 2, including commercial off-the-shelf equipment, may be used.

[0105] During maintenance of positioner assembly 1, it may be desirable to remove the first refrigerant and / or the second refrigerant from the respective internal channels. For example, such maintenance may be performed approximately once a year, although the frequency may depend on the specific installation and operation of the lithography apparatus LA. Different arrangements for removing the first / second refrigerant are possible.

[0106] In one arrangement, as shown in Figures 12 and 13, the positioner assembly 1 may also include a first refrigerant removal line 66 in fluid communication with the first internal passage 22. The first refrigerant removal line 66 may allow the removal of first refrigerant from the first internal passage 22.

[0107] During normal operation of the lithography apparatus LA, it may be desirable to prevent the first refrigerant from being removed from the first internal channel 22. Therefore, the first refrigerant removal line 66 may be fluidly isolated from the first internal channel. The first refrigerant removal line 66 can be isolated by a valve 661. During normal operation of the lithography apparatus LA, the valve 661 may shut off the first refrigerant removal line 66, thereby preventing the first refrigerant from flowing into the first refrigerant removal line 66.

[0108] Figures 12 and 13 show valve 661 located at the junction between the first refrigerant removal line 66 and the first refrigerant return line 62. Valve 661 may be a three-way valve. In this arrangement, during normal operation of the lithography apparatus LA, valve 661 may allow the first refrigerant to flow in the first refrigerant return line 62 while simultaneously closing the first refrigerant removal line 66.

[0109] It should be understood that, unlike that shown in Figures 12 and 13, valve 661 may be located separately away from the junction between the first refrigerant removal line 66 and the first refrigerant return line 62. Valve 661 may be a two-way valve. In this arrangement, during operation of the lithography apparatus LA, the first refrigerant in the first refrigerant return line 62 may not flow through valve 661.

[0110] During the removal of the first refrigerant, it may be desirable to control the flow of the first refrigerant in the first refrigerant removal line 66. Therefore, the first refrigerant removal line may also include a throttling device (not shown). Valve 661 may function as a throttling device during the removal of the first refrigerant and isolate the first refrigerant removal line 66 during normal operation of the lithography apparatus LA. Alternatively, the throttling device may be a separate device. The throttling device may be located downstream of valve 661.

[0111] After the first refrigerant has entered the first refrigerant removal line 66, it may be disposed of in different ways. For example, in the arrangement shown in Figure 12, the first refrigerant removal line may be vented to the atmosphere. An vent 669 may be provided for this purpose. Thus, the first refrigerant may be removed from the first internal passage 22 by venting to the atmosphere. The advantages of this arrangement include simple structure and low space requirements.

[0112] During maintenance, the first refrigerant may be allowed to heat up and boil into a gaseous state. Initially, the first refrigerant in the first internal passage 22 may be under high pressure. If the first refrigerant is allowed to drop directly to atmospheric pressure, it may become a gas-liquid mixture due to the pressure drop. The gaseous portion may be easily vented, while the liquid portion may require time to boil by absorbing heat from the surrounding environment.

[0113] Therefore, it may be desirable to keep the first refrigerant in a gaseous state during the discharge. As shown in Figure 12, the first refrigerant removal line may include a heater 662 configured to heat the first refrigerant before it is discharged into the atmosphere.

[0114] As an alternative to discharging the first refrigerant during maintenance, the removed first refrigerant may be temporarily stored and returned to the system after maintenance. This may allow the first refrigerant to be reused and reduce / avoid its consumption. As shown in Figure 13, the positioner assembly 1 may also include a first refrigerant storage container 76 in fluid connection with the first refrigerant removal line 66. The first refrigerant removed from the first internal passage 22 may be stored in the first refrigerant storage container 76.

[0115] Storing the first refrigerant in a gaseous state may require a large space, thus the first refrigerant storage container 76 may need to be large. However, to save space, the first refrigerant may be compressed before storage. As shown in Figure 13, the first refrigerant removal line 66 may also include a compressor 663 configured to compress the first refrigerant and allow it to flow to the first refrigerant storage container 76. The first refrigerant may be stored at a pressure higher than the pressure within the first internal passage 22 during normal operation. For example, the first refrigerant may be stored in the first refrigerant storage container 76 as a supercritical fluid.

[0116] After maintenance, the stored first refrigerant may flow back to the first internal passage 22. As shown in FIG13, the positioner assembly 1 may also include a first refrigerant re-injection line 68. The first refrigerant storage container 76 may be in fluid communication with the first internal passage 22 via the first refrigerant re-injection line 68. The first refrigerant re-injection line 68 may re-inject the first refrigerant at any suitable location. For example, as shown in FIG13, the re-injection point may be located upstream of the first buffer tank 72, such that the re-injected first refrigerant may be cooled before flowing into the first internal passage 22. Alternatively, the re-injection point may be located downstream of the first buffer tank 72.

[0117] The first refrigerant reinjection line 68 may be fluidly isolated from the first internal passage. A valve 681 may be provided on the first refrigerant reinjection line 68 to achieve isolation. This allows the first refrigerant reinjection line 68 to be isolated during normal operation of the lithography apparatus LA.

[0118] Since the first refrigerant may be stored at a pressure greater than the pressure within the first internal passage 22 during normal operation, it may need to be depressurized and / or re-expanded before being re-injected. Therefore, the first refrigerant re-injection line 68 may include a fluid expansion device (not shown) configured to expand the first refrigerant before it flows back into the first internal passage 22. A valve 681 may serve as both the fluid expansion device and to isolate the first refrigerant re-injection line 68 during normal operation of the lithography apparatus LA. Alternatively, the expansion device and valve 681 may be separate devices.

[0119] The contents disclosed above with reference to Figures 12 and 13 for the first refrigerant are equally applicable to the second refrigerant with necessary modifications. Therefore, as shown in Figure 12, a second refrigerant removal line 67 similar to the first refrigerant removal line 66 may be provided. Similarly, a valve 671 similar to valve 661 may be provided. If the second refrigerant is to be discharged, a heater 672 may be provided on the second refrigerant removal line 67, as shown in Figure 12, and / or a discharge port 679 may be provided at the outlet of the second refrigerant removal line. If the second refrigerant is to be stored, then, as shown in Figure 13, a compressor 673, and / or a second refrigerant storage container 77, and / or a second refrigerant return line 69, and / or a valve 691 may be provided.

[0120] It should also be noted that the first and second refrigerants may be handled in similar or different ways during maintenance operations. That is, both the first and second refrigerants may be discharged (as shown in Figure 12) or both may be stored (as shown in Figure 13). Alternatively, the arrangements of Figures 12 and 13 may be used in combination, such that the first refrigerant may be discharged while the second refrigerant may be stored, or vice versa. For example, the second refrigerant may be an readily available fluid such as nitrogen, and it may not be worthwhile to add the extra complexity of setting up and maintaining the necessary storage equipment.

[0121] The positioner component 1, as disclosed in various ways above, may be part of a lithography apparatus LA. This lithography apparatus may be used in methods for manufacturing equipment.

[0122] While this document may specifically refer to the application of photolithography apparatus in IC manufacturing, it should be understood that the photolithography apparatus described herein may also have other applications. Other possible applications include the fabrication of integrated optical systems, patterning and detection for magnetic domain memories, flat panel displays, liquid crystal displays (LCDs), thin-film magnetic heads, etc. Those skilled in the art will understand that in such alternative application scenarios, the terms “wafer” or “die” as used herein may in any case be considered synonymous with the more general terms “substrate” or “target portion,” respectively. The substrate mentioned herein may be processed before or after exposure in, for example, coating and developing equipment (typically used to apply a resist layer to the substrate and develop the exposed resist), metrology tools, and / or inspection tools. Where applicable, the disclosure herein may apply to such and other substrate processing tools. Furthermore, the substrate may be processed multiple times (e.g., for the fabrication of multilayer integrated circuits), therefore the term “substrate” as used herein may also refer to a substrate that already contains one or more processed layers.

[0123] Although the embodiments of the present invention have been specifically cited above in the context of optical lithography, it should be understood that the embodiments of the present invention may also be used in other application scenarios.

[0124] Several aspects of the present invention are described in the following numbered items. 1. An assembly (1) for a photolithography apparatus (LA), the assembly comprising: a thermal conditioning plate (2); a plurality of superconducting coils (5) for magnetically levitizing and linearly displacing a stage (9) thereon, wherein the plurality of superconducting coils are in thermal contact with the thermal conditioning plate; wherein: the thermal conditioning plate includes a first internal channel (22) for containing a first refrigerant and a second internal channel (23) for containing a second refrigerant; and the first internal channel and the second internal channel are thermally coupled to each other and fluidly isolated from each other, thereby achieving heat transfer between the first refrigerant and the second refrigerant while fluidly isolating the first refrigerant from the second refrigerant. 2. The assembly according to item 1, wherein the first internal channel comprises a gas chamber or a channel network. 3. The assembly according to item 1 or item 2, wherein the first internal channel extends together with the plurality of superconducting coils. 4. The assembly according to any of the preceding items, wherein the second internal channel comprises a channel network. 5. The assembly according to any of the preceding items, wherein the second internal channel extends together with the plurality of superconducting coils. 6. The component according to any of the preceding claims, wherein the second internal channel is provided at a position between the plurality of superconducting coils and the first internal channel. 7. The component according to any of the preceding claims, wherein the plurality of superconducting coils are disposed on the outer surface (21) of the heat-regulating plate. 8. The component according to any of claims 1 to 5, wherein the plurality of superconducting coils are provided within the first internal channel. 9. The component according to any of the preceding claims, further comprising: a control system (71) configured to control the flow of the first refrigerant and the second refrigerant in the first internal channel and the second internal channel, respectively, wherein the second refrigerant has a lower freezing point than the first refrigerant. 10. The component according to claim 9, wherein the control system is configured to allow the second refrigerant to flow in the second internal channel, thereby cooling the first refrigerant in the heat-regulating plate and the first internal channel. 11. The component according to claim 10, wherein the control system is configured to allow the second refrigerant to flow in the second internal channel, thereby cooling the heat-regulating plate to and / or maintaining it at a temperature below the freezing point of the first refrigerant. 12. The component according to any one of clauses 9 to 11, wherein the control system is configured to cause the first refrigerant to flow in the first internal channel, thereby cooling the heat-regulating plate. 13. The component according to clause 12, wherein the control system is configured to cause the first refrigerant to flow in the first internal channel, thereby cooling the heat-regulating plate to a temperature below the boiling point of the first refrigerant.14. The component according to claim 12 or 13, wherein the control system is configured to stop the flow of the first refrigerant in the first internal channel before the temperature of the heat-regulating plate reaches the freezing point of the first refrigerant. 15. The component according to any one of claims 9 to 14, wherein the control system is configured to: allow the first refrigerant to flow in the first internal channel, then stop the flow of the first refrigerant; and then allow the second refrigerant to flow in the second internal channel. 16. The component according to any one of claims 9 to 14, wherein the control system is configured to: cool the heat-regulating plate by allowing the first refrigerant to flow in the first internal channel; then stop the flow of the first refrigerant when the heat-regulating plate has reached a temperature below the boiling point of the first refrigerant; and then allow the second refrigerant to flow in the second internal channel. 17. The component according to any one of the preceding claims, further comprising: a first refrigerant removal line in fluid communication with the first internal channel, wherein the first refrigerant removal line is configured to remove the first refrigerant from the first internal channel. 18. The assembly of claim 17, wherein the first refrigerant removal line is fluidly isolated from the first internal passage. 19. The assembly of claim 17 or claim 18, wherein the first refrigerant removal line further includes a throttling device. 20. The assembly of any one of claims 17 to 19, wherein the first refrigerant removal line is discharged to the atmosphere. 21. The assembly of claim 20, wherein the first refrigerant removal line includes a heater configured to heat the first refrigerant before it is discharged to the atmosphere. 22. The assembly of any one of claims 17 to 19, further comprising a first refrigerant storage container fluidly connected to the first refrigerant removal line. 23. The assembly of claim 22, wherein the first refrigerant removal line includes a compressor configured to compress the first refrigerant and cause the first refrigerant to flow to the first refrigerant storage container. 24. The component according to claim 22 or 23, further comprising: a first refrigerant re-injection line, wherein the first refrigerant storage container is in fluid communication with the first internal channel via the first refrigerant re-injection line. 25. The component according to claim 24, wherein the first refrigerant re-injection line is fluidly isolating from the first internal channel. 26. The component according to claim 24 or 25, wherein the first refrigerant re-injection line includes: a fluid expansion device configured to expand the first refrigerant before allowing it to flow back into the first internal channel. 27. The component according to claim 26, wherein the fluid expansion device is configured to selectively fluidly isolate the first refrigerant re-injection line from the first internal channel.28. The component according to any one of the preceding claims, further comprising: a second refrigerant removal line in fluid communication with the second internal passage, wherein the second refrigerant removal line is configured to remove the second refrigerant from the second internal passage. 29. The component according to claim 28, wherein the second refrigerant removal line is fluidly isolated from the second internal passage. 30. The component according to claim 28 or 29, wherein the second refrigerant removal line further comprises a throttling device. 31. The component according to any one of claims 28 to 30, wherein the second refrigerant removal line is discharged to the atmosphere. 32. The component according to claim 31, wherein the second refrigerant removal line includes: a heater configured to heat the second refrigerant before it is discharged to the atmosphere. 33. The component according to any one of claims 28 to 30, further comprising: a second refrigerant storage container in fluid communication with the second refrigerant removal line. 34. The assembly of claim 33, wherein the second refrigerant removal line comprises: a compressor configured to compress the second refrigerant and allow the second refrigerant to flow to the second refrigerant storage container. 35. The assembly of claim 33 or 34, further comprising: a second refrigerant re-injection line, wherein the second refrigerant storage container is in fluid communication with the second internal channel via the second refrigerant re-injection line. 36. The assembly of claim 35, wherein the second refrigerant re-injection line is fluidly isolating from the second internal channel. 37. The assembly of claim 35 or 36, wherein the second refrigerant re-injection line comprises: a fluid expansion device configured to expand the second refrigerant before allowing it to flow back into the second internal channel. 38. The assembly of claim 37, wherein the fluid expansion device is configured to selectively fluidly isolate the second refrigerant re-injection line from the second internal channel. 39. A photolithography apparatus comprising the assembly of any of the preceding claims. 40. A method of operating a component (1) according to any one of claims 1 to 8, comprising: flowing a first refrigerant and a second refrigerant in a first internal channel and a second internal channel, respectively, wherein the second refrigerant has a lower freezing point than the first refrigerant. 41. The method according to claim 40, further comprising: cooling the heat-regulating plate and the first refrigerant in the first internal channel through the second refrigerant in the second internal channel. 42. The method according to claim 41, wherein the flow of the second refrigerant in the second internal channel causes the heat-regulating plate to be cooled to and / or maintained at a temperature below the freezing point of the first refrigerant. 43. The method according to any one of claims 40 to 42, wherein the flow of the first refrigerant in the first internal channel cools the heat-regulating plate.44. The method of claim 43, wherein the flow of the first refrigerant in the first internal channel cools the heat-regulating plate to a temperature below the boiling point of the first refrigerant. 45. The method of claim 43 or claim 44, further comprising: stopping the flow of the first refrigerant in the first internal channel before the temperature of the heat-regulating plate reaches the freezing point of the first refrigerant. 46. The method of any one of claims 40 to 45, comprising: allowing the first refrigerant to flow in the first internal channel, subsequently stopping the flow of the first refrigerant, and subsequently allowing the second refrigerant to flow in the second internal channel. 47. The method of claim 46, wherein: the flow of the first refrigerant in the first internal channel cools the heat-regulating plate; and the stopping of the flow of the first refrigerant is performed when the heat-regulating plate has reached a temperature below the boiling point of the first refrigerant. 48. The method of any one of claims 40 to 47, further comprising: venting the first refrigerant from the first internal channel to the atmosphere during maintenance of the assembly. 49. The method according to any one of claims 40 to 47, further comprising: removing the first refrigerant from the first internal channel and storing the first refrigerant during maintenance of the component. 50. The method according to claim 49, wherein the first refrigerant is stored in a compressed manner. 51. The method according to claim 49 or claim 50, further comprising: returning the first refrigerant to the first internal channel after maintenance of the component. 52. The method according to claim 51, further comprising: expanding the first refrigerant before returning it to the first internal channel. 53. The method according to any one of claims 40 to 52, further comprising: venting the second refrigerant from the second internal channel to the atmosphere during maintenance of the component. 54. The method according to any one of claims 40 to 52, further comprising: removing the second refrigerant from the second internal channel and storing the second refrigerant during maintenance of the component. 55. The method according to claim 54, wherein the second refrigerant is stored in a compressed manner. 56. The method according to claim 54 or 55, further comprising: after maintenance of the component, recirculating the second refrigerant back to the second internal channel. 57. The method according to claim 55, further comprising: expanding the second refrigerant before recirculating it back to the second internal channel. 58. A method of manufacturing an apparatus, comprising the method according to any one of claims 40 to 47. 59. A method of manufacturing an apparatus using a photolithography apparatus according to claim 39.

[0125] Although specific embodiments of the present invention have been described above, it should be understood that the present invention may be implemented in ways other than those described.

[0126] The above description is intended to be illustrative and not limiting. Therefore, those skilled in the art will understand that modifications may be made to the invention without departing from the scope of the claims described below.

Claims

1. A component (1) for a photolithography apparatus (LA), the component comprising: A heat-regulating plate (2); a plurality of superconducting coils (5) for magnetically levitizing and linearly displacing a stage (9) on the plurality of superconducting coils, wherein the plurality of superconducting coils are in thermal contact with the heat-regulating plate; wherein: the heat-regulating plate includes a first internal channel (22) for containing a first refrigerant and a second internal channel (23) for containing a second refrigerant; and the first internal channel and the second internal channel are thermally coupled to each other and fluidly isolated from each other, thereby enabling heat transfer between the first refrigerant and the second refrigerant while the first refrigerant and the second refrigerant are fluidly isolated from each other.

2. The component of claim 1, wherein the first internal channel comprises: Air chambers or channel networks; And / or wherein the first internal channel extends together with the plurality of superconducting coils; And / or wherein the second internal channel comprises a channel network, wherein the second internal channel extends together with the plurality of superconducting coils; and / or wherein the second internal channel is provided at a location between the plurality of superconducting coils and the first internal channel.

3. The component according to claim 1 or 2, wherein the plurality of superconducting coils are disposed on the outer surface (21) of the thermal adjustment plate, or wherein the plurality of superconducting coils are provided within the first internal channel.

4. The component according to any one of the preceding claims further comprises: The control system (71) is configured to control the flow of the first refrigerant and the second refrigerant in the first internal channel and the second internal channel, respectively, wherein the second refrigerant has a lower freezing point than the first refrigerant.

5. The component of claim 4, wherein the control system is configured to cause the second refrigerant to flow in the second internal channel, thereby cooling the heat-regulating plate and the first refrigerant in the first internal channel; The control system is preferably configured to allow the second refrigerant to flow in the second internal channel, thereby cooling the thermal regulating plate to and / or maintaining it at a temperature below the freezing point of the first refrigerant. And / or wherein the control system is configured to cause the first refrigerant to flow in the first internal channel, thereby cooling the thermal regulating plate; The control system is preferably configured to allow the first refrigerant to flow in the first internal channel, thereby cooling the thermal regulating plate to a temperature below the boiling point of the first refrigerant. And / or wherein the control system is configured to stop the flow of the first refrigerant in the first internal channel before the temperature of the heat regulating plate reaches the freezing point of the first refrigerant.

6. The component of claim 5, wherein the control system is configured to: allow the first refrigerant to flow in the first internal channel, and then stop the flow of the first refrigerant; and then allow the second refrigerant to flow in the second internal channel; or wherein the control system is configured to: cool the thermal regulating plate by allowing the first refrigerant to flow in the first internal channel; Then, when the heat regulating plate has reached a temperature below the boiling point of the first refrigerant, the flow of the first refrigerant is stopped. And then the second refrigerant flows in the second internal channel.

7. The component according to any one of the preceding claims further comprises: A first refrigerant removal line is in fluid communication with the first internal channel, wherein the first refrigerant removal line is configured to remove the first refrigerant from the first internal channel.

8. The component of claim 7, wherein the first refrigerant removal line is fluidly isolated from the first internal passage; and / or wherein the first refrigerant removal line further includes a throttling device; And / or the first refrigerant removal line is discharged to the atmosphere; The first refrigerant removal line preferably includes a heater configured to heat the first refrigerant before it is released into the atmosphere.

9. The component of claim 8, further comprising a first refrigerant storage container in fluid connection with the first refrigerant removal line; The first refrigerant removal line desirably includes: a compressor configured to compress the first refrigerant and allow the first refrigerant to flow to the first refrigerant storage container; it also desirably includes: a first refrigerant re-injection line, wherein the first refrigerant storage container is in fluid communication with the first internal channel via the first refrigerant re-injection line; wherein the first refrigerant re-injection line is desirably fluidly isolated from the first internal channel; wherein the first refrigerant re-injection line desirably includes: a fluid expansion device configured to expand the first refrigerant before allowing it to flow back into the first internal channel; wherein the fluid expansion device is desirably configured to selectively fluidly isolate the first refrigerant re-injection line from the first internal channel.

10. The component according to any one of the preceding claims, further comprising: A second refrigerant removal line is in fluid communication with the second internal passage, wherein the second refrigerant removal line is configured to remove the second refrigerant from the second internal passage.

11. The component of claim 10, wherein the second refrigerant removal line is fluidly isolated from the second internal passage; wherein the second refrigerant removal line desirably further includes a throttling device; The second refrigerant removal line is intended to release the refrigerant into the atmosphere; The second refrigerant removal line preferably includes: a heater configured to heat the second refrigerant before it is released into the atmosphere; preferably also includes: a second refrigerant storage container fluidly connected to the second refrigerant removal line; wherein the second refrigerant removal line preferably includes: a compressor configured to compress the second refrigerant and cause the second refrigerant to flow to the second refrigerant storage container.

12. The component of claim 11, further comprising: The second refrigerant re-injection line, wherein the second refrigerant storage container is in fluid communication with the second internal channel via the second refrigerant re-injection line; Ideally, the second refrigerant reinjection line and the second internal channel should be fluidly isolated. The second refrigerant re-injection line preferably includes a fluid expansion device configured to expand the second refrigerant before it is returned to the second internal passage; The fluid expansion device is preferably configured to selectively isolate the second refrigerant re-injection line from the second internal channel fluid.

13. A photolithography apparatus comprising the components according to any one of the preceding claims.

14. A method of operating component (1) according to any one of claims 1 to 3, comprising: The first refrigerant and the second refrigerant flow in the first internal channel and the second internal channel, respectively, wherein the second refrigerant has a lower freezing point than the first refrigerant.

15. A method of manufacturing equipment, comprising the method according to claim 14 or the photolithography apparatus according to claim 13.

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