Line assembly and installation for semiconductor technology

Abstract

The invention relates to a line assembly (70, 90) for a fluid line (39, 42, 43) of an installation (1, 101) for semiconductor technology, the line assembly comprising at least one damping element (72.1, 72.2, 92) for damping acoustic oscillations in the fluid (79), wherein the line assembly (70, 90) has a compressible primary volume (77.1, 77.2, 97) into which the damping element (72.1, 72.2, 92) moves at least in part when the damping element is deformed. The line assembly (70, 90) is characterised in that it comprises a compressible secondary volume (78.1, 78.2, 98) which is formed as part of the primary volume (77.1, 77.2, 97). The invention also relates to an installation (1, 101) for semiconductor technology comprising a line assembly (70, 90) according to any one of the embodiments described.

Description

[0001] Pipeline construction group and plant for semiconductor technology

[0002] The present application claims priority from German patent application DE 10 2024 207 790.9 dated 15.08.2024, the content of which is incorporated herein in full by reference.

[0003] The invention relates to a conductor assembly, in particular for use in a projection exposure system for semiconductor lithography and a system for semiconductor technology, in particular a projection exposure system.

[0004] To enable ever smaller feature sizes on semiconductor devices, in accordance with Moore's Law, the demands on the equipment used to manufacture them are also increasing, particularly projection exposure systems for semiconductor lithography. Current systems of this kind feature cooling systems for the thermal stabilization of the optics and structures used.

[0005] The cooling lines or channels used in the cooling system can be routed through both the optical elements and the structural components of the system. Typically, the structures to be cooled are interconnected by piping assemblies and networks, which are in turn mounted on the system structures themselves. Active cooling ensures both maximum heat dissipation and precise controllability of the system. The flowing fluid also improves heat transfer across the surfaces through which it flows (forced convection).

[0006] Water is typically used as the cooling medium due to its high heat capacity and availability; other fluids are also conceivable.

[0007] Especially in the development of water-cooled optical elements for projection imaging systems, their supporting structures and infrastructure, pressure fluctuations / waves transported and transmitted via the fluid (e.g., water) play a crucial role in the performance of the overall system, particularly the imaging projection optics, and the image quality on a wafer. These pressure waves, which propagate through the fluid at the speed of sound (e.g., approximately 1500 m / s in acoustically hard environments such as stainless steel), are referred to below as WLA – Water Line Acoustics.

[0008] The sources and triggering mechanisms for water-induced vibrations (WLA) are diverse. One example is flow-induced vibrations (FIV), which arise from persistent periodic and random fluctuations in the flow, i.e., turbulence, depending on local geometric boundary conditions and the upstream and downstream flow conditions. These hydrodynamic fluctuations lead to the coupling of acoustic pressure waves or vibrations, which propagate as WLA both downstream and upstream in the fluid and, depending on the geometry of the cooling circuit, can lead to standing waves.

[0009] Another triggering mechanism involves transmitted mechanical structural vibrations and the interaction between structural components and the fluid. Both the mechanical structural vibrations themselves and the interaction exhibit frequency-dependent amplitudes. For example, in current systems, mechanical structural vibrations are transmitted via pipe supports to the pipe walls and thus directly into the fluid. Cooling channels integrated directly into structural components can also absorb mechanical structural vibrations directly via the fluid itself. Additionally, acoustic vibrations (disturbances) from the environment can also affect the fluid. WLA (Water-Loaded Acoustic Vibration) is only triggered by FIV (Fluid Induction Vibration) in an actively flowing cooling system. The other mechanisms also occur in a system simply filled with fluid, without active flow.Therefore, even a countermeasure, such as switching off active cooling and thus shutting off the flow, does not provide a complete remedy against WLA, but only against FIV as a source.

[0010] To reduce the pressure fluctuations introduced into the fluid system, which manifest as acoustic vibrations, to a specified level, (hardware) measures are required. These can be actively operated / controlled or, preferably, passive measures. One solution for reducing, suppressing, or damping acoustic vibrations in the fluid column (WLA) is the use of piping assemblies made of viscoelastic materials with an adjacent gas space.

[0011] The gas space corresponds to a spatial region designed to provide sufficient space (volume) for deformation of damping elements made from the viscoelastic material. This space (volume) is necessary to ensure free deformation of the damping element and thus optimal damping performance. When using a viscoelastic material with an adjacent gas space, permeation of water or another fluid into the gas space and vice versa can occur. This permeation process, in which a substance (permeate) penetrates or passes through a solid, is fundamentally dependent on the gradient of the permeate's chemical potential, but in the case described here, it can be reduced to a dependence primarily on the partial pressure difference between the fluid and the gas space.The partial pressure difference, in turn, depends directly on the temperature difference between the fluid volume and the gas space. Since the temperature in a projection exposure system is maintained at a very precise, constant value, and the cooling fluid can simultaneously have a higher temperature, this permeation process is sometimes significantly accelerated. Furthermore, due to the lower dew point, water vapor condenses within the gas space. This has the disadvantage that over several months or years, the gas space can become completely filled with water, leaving no space available for the deformation of the viscoelastic material necessary for damping. The damping effect of the viscoelastic material or damping element can thus be almost completely suppressed by filling the gas space with water.

[0012] The object of the present invention is to provide a device for eliminating the disadvantages of the prior art explained above. This object is achieved by a device with the features of independent claim 1. The dependent claims relate to advantageous embodiments and variants of the invention.

[0013] A conduit assembly according to the invention comprises a fluid line for a semiconductor technology system with at least one damping element for damping acoustic vibrations in the fluid. The conduit assembly has a compressible primary volume into which the damping element moves, at least partially, when deformed. The conduit assembly is characterized by having a compressible secondary volume, which is formed as part of the primary volume. In other words, the primary volume includes the secondary volume. The volume remaining in the primary volume after subtracting the secondary volume is called the sacrificial volume, since it is filled with fluid over time due to permeation of the fluid into the primary volume. For the purposes of the invention, the primary volume is a spatial region defined when the damping element is undeformed.The spatial area of ​​the primary volume defined in this way, which is bounded on at least one side by the damping element, does not change even if the damping element is deformed, although the movement of the deformation element, which at least partially limits the volume, causes a change in the original primary volume.

[0014] The secondary volume ensures that even when the sacrificial volume is predominantly filled with a fluid, such as water, the damping element still has a sufficient space, defined by the secondary volume, available for deformation. The secondary volume is delimited from the sacrificial volume in such a way that fluid permeation into the secondary volume does not occur, or only in negligible amounts (e.g., less than 5% of the secondary volume) over a comparatively long period, such as more than 10 years, preferably more than 20 years, and particularly preferably more than 50 years.

[0015] In particular, the proportion of the secondary volume to the primary volume can be at least 1%, preferably at least 10%, and most preferably at least 50%. Depending on the volume required for deformation of the damping element to achieve sufficient damping, the percentage of the secondary volume to the primary volume can be determined. For the purposes of this invention, the proportion of the secondary volume is to be understood as the fluid-free area remaining over the lifetime of the device. It is known to those skilled in the art that, given a chemical gradient, permeation cannot be completely prevented indefinitely in reality, and this proportion is negligible for the purposes of this invention. The information provided in the preceding paragraph serves to indicate the order of magnitude of the fluid permeation that can be expected in reality.

[0016] In another embodiment, the damping element can comprise a viscoelastic material. Viscoelastic materials, due to their complex, frequency-dependent modulus of elasticity (E-modulus), which consists of an elastic storage modulus (E') and a complex loss modulus (E"), exhibit a damping effect that depends on the frequency and amplitude of the material's deformation. With suitable design, this effect can be used to dampen acoustic vibrations in the fluid.

[0017] Furthermore, the stiffness of the secondary volume can be at least a factor of 5 to 5000 smaller, preferably at least a factor of 5 to 500 smaller, and particularly preferably at least a factor of 5 to 100 smaller, compared to the stiffness of the damping element. This factor depends on the design of the viscoelastic material of the damping element. The secondary volume can be designed as a spring that generates a force opposing the force caused by the deformation of the viscoelastic material.

[0018] In a further embodiment, the boundary of the secondary volume can have a permeation coefficient that is 2 times, preferably 100 times, and particularly preferably 1000 times lower than that of the viscoelastic damping element. The lower the permeability of the fluid used, such as water, into the secondary volume, the longer it may take for the secondary volume to also be filled by the fluid. Furthermore, the secondary volume can be designed as a continuous volume. For example, the secondary volume can be separated from the sacrificial volume by a separating element in the form of a film, thus forming a continuous secondary volume. Alternatively, the secondary volume can be designed as a volume within the sacrificial volume, i.e., it can be at least predominantly surrounded by the sacrificial volume.

[0019] In addition, the secondary volume can have at least two subvolumes. This is the case, for example, when the secondary volume comprises individual deformation elements with comparatively small enclosed volumes, which are introduced into the primary volume like bulk material. Alternatively, the secondary volume can be in the form of a film with separate air pockets, as is known, for example, from bubble wrap. This film can be fixed at any point within the primary volume or inserted loosely and / or in individual sections.

[0020] Furthermore, the secondary volume can be freely movable within the primary volume. This means the secondary volume can move freely within the primary volume without being connected to any other component of the piping assembly. This applies to both a single, continuous secondary volume and multiple partial secondary volumes. This has the advantage that, in the case of a sacrificial volume largely or completely filled with fluid, the secondary volume assumes the temperature of the fluid. Consequently, a gaseous fluid diffusing into the secondary volume no longer condenses due to the lack of a temperature gradient. Therefore, in the case of water, once 100% water vapor saturation is reached, the chemical gradient necessary for permeation becomes almost zero, thus stopping or further slowing down permeation into the secondary volume.

[0021] In particular, the foil may contain aluminum, especially if it is coated with aluminum at least in sections. The aluminum coating has the advantage of almost completely preventing water permeation. Furthermore, aluminum coatings can exhibit sufficient elasticity to minimize or completely eliminate the risk of damage or cracking due to stretching and / or compression of the foil. The foil may, for example, be a metallized polyethylene terephthalate (PET) film. Metallized PET films are well-known in packaging technology as a direct substitute for aluminum foil.For the same film thickness, PET films are characterized by higher tear resistance and flexural rigidity, so the composite material created by vapor deposition of the metal does not wrinkle as easily as aluminum foil. Furthermore, multilayer films with several stacked layers of films of varying thicknesses and materials can also be used. Both the film material and the vapor-deposited layer on each layer can differ. The films can contain the following materials:

[0022] Track-etched polycarbonate film (PCTE), liquid crystal polymers (LCP), polyethylene naphthalate (PEN), polyurethane (PUR), polypropylene (PP), semi-fluorinated polymers (ECTFE); ethylene tetrafluoroethylene (ETFE); polysulfone (PSU), polyvinyl fluoride (PVF)

[0023] Polyvinylidene fluoride (PVDF), polyimides (PI). Besides aluminum, the coating can also include gold, silver, or other materials that can be vapor-deposited onto the film or applied using other methods, whereby the elasticity requirements should correspond to those explained above. Alternatively, given specific boundary conditions, the film can also be a pure metal foil, such as an aluminum foil.

[0024] In another embodiment, the secondary volume can be filled with a compressible substance or mixture of substances.

[0025] In particular, the substance may be at least partially composed of a compressible fluid, wherein the fluid may comprise one of the following fluids:

[0026] Dry air, extremely clean dry air (XCDA), nitrogen, oxygen, carbon dioxide, alkanes (methane, ethane, propane, butane, isobutane), noble gases (helium, neon, argon, krypton, xenon) or fluorinated gases, such as SF6, CF4C5-FN, C4-FN, and all fluorinated refrigerants.

[0027] In a further embodiment of the invention, the material can be at least partially designed as a compressible foam, wherein the foam can comprise one of the following materials:

[0028] Polyurethane (PUR / PU) - flexible foam, acrylonitrile butadiene rubber (NBR), fluororubber (FKM), perfluoroelastomer (FFKM), polyethylene (PE), silicone foam, polystyrene foams (such as PS-E, XPS), polyphenylene ether (PP-E) and polyvinyl chloride (PVC-E), sponge rubber or cellular rubber. Other thermoplastic foams and elastomeric foams are also conceivable.

[0029] A compressible foam has the advantage that the material used for the foam can have a comparatively low permeation coefficient compared to the viscoelastic material of the fluid line, which further slows down the permeation of the fluid into the secondary volume. The gas in the foam can be one of the gases described above.

[0030] In a further embodiment of the invention, a fluid arranged in the primary volume and / or secondary volume can have a permeability that is 25 times smaller, preferably 50 times smaller and particularly preferably 100 times smaller than that of air via the viscoelastic material and / or via the thin-walled film and the viscoelastic material into the fluid.

[0031] In particular, the fluid may contain a gas from the following list:

[0032] Tetrafluoromethane (CF4), alkanes (methane, ethane, propane, butane, isobutane), noble gases (helium, neon, argon, krypton, xenon) or fluorinated gases, such as SF6, C5-FN, C4-FN, and all fluorinated refrigerants.

[0033] The permeation of gas present in the primary and / or secondary volume into the fluid line can be advantageously reduced by using a gas, such as the one mentioned above, with a low permeability compared to the air typically present in the primary volume under the given circumstances. This lower permeation can be attributed, on the one hand, to the larger molecules of the gases compared to air. On the other hand, the permeation is reduced by the use of a polar material for the hose, such as fluororubber, or, in the case of noble gases, by their nonpolar properties.

[0034] An inventive system for semiconductor technology comprises a conductor assembly according to one of the embodiments described above.

[0035] In particular, the system can be configured as a wafer inspection system, a reticle inspection system, a reticle repair system, or a projection exposure system for semiconductor lithography.

[0036] Exemplary embodiments and variants of the invention are explained in more detail below with reference to the drawing. The drawing shows

[0037] Figure 1 schematically shows a projection exposure system for EUV projection lithography in meridional section.

[0038] Figure 2 schematically shows a projection exposure system for DUV projection lithography in meridional section.

[0039] Figure 3 shows a schematic representation of a part of an EUV projection exposure system known from the prior art,

[0040] Figure 4 shows two embodiments of the invention, and

[0041] Figure 5 shows another embodiment of the invention.

[0042] The following section describes, with reference to Figure 1, the essential components of a projection exposure system 1 for microlithography. The description of the basic structure of the projection exposure system 1 and its components is not intended to be restrictive.

[0043] One embodiment of a lighting system 2 of the projection exposure system 1 has, in addition to a radiation source 3, a lighting optic 4 for illuminating an object field 5 in an object plane 6. In an alternative embodiment, the light source 3 can also be provided as a separate module from the rest of the lighting system. In this case, the lighting system does not include the light source 3.

[0044] A reticle 7 located in object field 5 is illuminated. The reticle 7 is held by a reticle holder 8. The reticle holder 8 can be moved, particularly in a scanning direction, via a reticle displacement drive 9.

[0045] Figure 1 shows a Cartesian xyz coordinate system for illustrative purposes. The x-direction runs perpendicular to the plane of the drawing. The y-direction runs horizontally, and the z-direction runs vertically. In Figure 1, the scan direction runs along the y-direction. The z-direction runs perpendicular to the object plane 6.

[0046] The projection exposure system 1 comprises a projection optic 10. The projection optic 10 serves to image the object field 5 onto an image field 11 in an image plane 12. The image plane 12 is parallel to the object plane 6. Alternatively, an angle other than 0° between the object plane 6 and the image plane 12 is also possible.

[0047] A structure on the reticulum 7 is imaged onto a photosensitive layer of a wafer 13 located in the image plane 12 within the image field 11. The wafer 13 is held by a wafer holder 14. The wafer holder 14 can be moved, particularly along the y-direction, via a wafer transfer drive 15. The movement of the reticulum 7 via the reticulum transfer drive 9 and of the wafer 13 via the wafer transfer drive 15 can be synchronized.

[0048] Radiation source 3 is an EUV radiation source. Specifically, radiation source 3 emits EUV radiation 16, which is also referred to below as useful radiation, illumination radiation, or illumination light. The useful radiation has a wavelength in the range between 5 nm and 30 nm. Radiation source 3 can be a plasma source, for example, an LPP source (laser-produced plasma) or a DPP source (gas-discharged produced plasma). It can also be a synchrotron-based radiation source. Radiation source 3 can be a free-electron laser (FEL).

[0049] The illumination radiation 16 emanating from the radiation source 3 is focused by a collector 17. The collector 17 can be a collector with one or more ellipsoidal and / or hyperboloid reflective surfaces. The at least one reflective surface of the collector 17 can be illuminated with the illumination radiation 16 at grazing incidence (Gl), i.e., with angles of incidence greater than 45° relative to the normal direction of the mirror surface, or at normal incidence (NI), i.e., with angles of incidence less than 45°. The collector 17 can be structured and / or coated to optimize its reflectivity for the useful radiation and to suppress stray light.

[0050] After the collector 17, the illumination radiation 16 propagates through an intermediate focus in an intermediate focal plane 18. The intermediate focal plane 18 can represent a separation between a radiation source module, comprising the radiation source 3 and the collector 17, and the illumination optics 4.

[0051] The illumination optics 4 comprise a deflecting mirror 19 and, downstream in the beam path, a first faceted mirror 20. The deflecting mirror 19 can be a planar deflecting mirror or, alternatively, a mirror with an effect that influences the beam beyond the mere deflection effect. Alternatively or additionally, the deflecting mirror 19 can be designed as a spectral filter that separates a useful wavelength of the illumination radiation 16 from stray light of a different wavelength. If the first faceted mirror 20 is arranged in a plane of the illumination optics 4 that is optically conjugate to the object plane 6 as the field plane, it is also referred to as a field faceted mirror. The first faceted mirror 20 comprises a plurality of individual first facets 21, which are hereinafter also referred to as field facets. Only a few of these facets 21 are shown in Fig. 1 as examples.The first facets 21 can be designed as macroscopic facets, in particular as rectangular facets or as facets with an arcuate or semicircular border contour. The first facets 21 can be designed as planar facets or alternatively as convexly or concavely curved facets.

[0052] As is known, for example, from DE 10 2008 009 600 A1, the first facets 21 themselves can each be composed of a plurality of individual mirrors, in particular a plurality of micromirrors. The first facet mirror 20 can in particular be designed as a microelectromechanical system (MEMS system). For details, reference is made to DE 10 2008 009 600 A1.

[0053] Between the collector 17 and the deflecting mirror 19, the illumination radiation 16 runs horizontally, i.e. along the y-direction.

[0054] In the beam path of the illumination optics 4, a second faceted mirror 22 is arranged downstream of the first faceted mirror 20. If the second faceted mirror 22 is arranged in a pupil plane of the illumination optics 4, it is also referred to as a pupil faceted mirror. The second faceted mirror 22 can also be arranged at a distance from a pupil plane of the illumination optics 4. In this case, the combination of the first faceted mirror 20 and the second faceted mirror 22 is also referred to as a specular reflector. Specular reflectors are known from US 2006 / 0132747 A1, EP 1 614 008 B1, and US 6,573,978.

[0055] The second facet mirror 22 comprises a plurality of second facets 23. In the case of a pupil facet mirror, the second facets 23 are also referred to as pupil facets.

[0056] The second facets 23 can also be macroscopic facets, which may, for example, have round, rectangular, or hexagonal edges, or alternatively, facets composed of micromirrors. Reference is also made to DE 102008 009 600 A1 in this regard.

[0057] The second facets 23 can have planar or, alternatively, convex or concave curved reflective surfaces. The illumination optics 4 thus form a doubly faceted system. This basic principle is also known as a honeycomb condenser (fly's eye integrator).

[0058] It can be advantageous not to arrange the second faceted mirror 22 exactly in a plane that is optically conjugate to a pupil plane of the projection optics 10. In particular, the pupil faceted mirror 22 can be arranged tilted relative to a pupil plane of the projection optics 10, as described, for example, in DE 10 2017 220 586 A1.

[0059] With the aid of the second faceted mirror 22, the individual first facets 21 are imaged into the object field 5. The second faceted mirror 22 is the last beam-shaping, or indeed the last, mirror for the illumination radiation 16 in the beam path before the object field 5.

[0060] In another embodiment of the illumination optics 4, not shown, a transmission optic can be arranged in the beam path between the second faceted mirror 22 and the object field 5, which contributes in particular to imaging the first facets 21 into the object field 5. The transmission optic can have exactly one mirror, or alternatively two or more mirrors, which are arranged one behind the other in the beam path of the illumination optics 4. The transmission optic can in particular comprise one or two mirrors for normal incidence (Nl mirrors, normal incidence mirrors) and / or one or two mirrors for grazing incidence (Gl mirrors, grazing incidence mirrors).

[0061] In the embodiment shown in Fig. 1, the lighting optics 4 has exactly three mirrors after the collector 17, namely the deflecting mirror 19, the field facet mirror 20 and the pupil facet mirror 22.

[0062] In a further embodiment of the illumination optics 4, the deflecting mirror 19 can also be omitted, so that the illumination optics 4 after the collector 17 can then have exactly two mirrors, namely the first faceted mirror 20 and the second faceted mirror 22. The imaging of the first facets 21 by means of the second facets 23 or with the second facets 23 and a transmission optic into the object plane 6 is regularly only an approximate imaging.

[0063] The projection optics 10 comprise a plurality of mirrors Mi, which are numbered according to their arrangement in the beam path of the projection exposure system 1.

[0064] In the example shown in Figure 1, the projection optics 10 comprises six mirrors M1 to M6. Alternatives with four, eight, ten, twelve, or any other number of mirrors Mi are also possible. The penultimate mirror M5 and the last mirror M6 each have an aperture for the illumination radiation 16. The projection optics 10 is a double-obscured optic. The projection optics 10 has an image-side numerical aperture greater than 0.5, and which can also be greater than 0.6, for example, 0.7 or 0.75.

[0065] The reflective surfaces of the mirrors Mi can be designed as freeform surfaces without an axis of rotational symmetry. Alternatively, the reflective surfaces of the mirrors Mi can be designed as aspherical surfaces with exactly one axis of rotational symmetry of the reflective surface shape. The mirrors Mi, like the mirrors of the illumination optics 4, can have highly reflective coatings for the illumination radiation 16. These coatings can be designed as multilayer coatings, in particular with alternating layers of molybdenum and silicon.

[0066] The projection optics 10 have a large object-image offset in the y-direction between a y-coordinate of a center of the object field 5 and a y-coordinate of the center of the image field 11. This object-image offset in the y-direction can be approximately as large as a z-distance between the object plane 6 and the image plane 12.

[0067] The projection optics 10 can be anamorphic. In particular, they have different image scales βx, βy in the x and y directions. The two image scales βx, βy of the projection optics 10 are preferably (βx, βy) = (+ / - 0.25, + / - 0.125). A positive image scale β indicates an image without image inversion. A negative sign for the image scale β indicates an image with image inversion.

[0068] The projection optics 10 thus lead to a reduction in the x-direction, that is, in the direction perpendicular to the scan direction, in a ratio of 4:1.

[0069] The projection optics 10 lead to a reduction of 8:1 in the y-direction, that is, in the scan direction.

[0070] Other magnification ratios are also possible. Magnification ratios with the same sign and absolute values ​​in the x and y directions, for example with absolute values ​​of 0.125 or 0.25, are also possible.

[0071] The number of intermediate image planes in the x- and y-directions in the beam path between the object field 5 and the image field 11 can be the same or, depending on the design of the projection optics 10, different. Examples of projection optics with different numbers of such intermediate images in the x- and y-directions are known from US 2018 / 0074303 A1.

[0072] Each pupil facet 23 is assigned to exactly one of the field facets 21 to form an illumination channel for illuminating the object field 5. This can result, in particular, in illumination according to Köhler's principle. The far field is divided into a multitude of object fields 5 by means of the field facets 21. The field facets 21 generate a plurality of images of the intermediate focus on the pupil facets 23 assigned to each of them.

[0073] The field facets 21 are each superimposed on the reticulum 7 by an associated pupil facet 23 to illuminate the object field 5.

[0074] The illumination of object field 5 is particularly homogeneous. It preferably exhibits a uniformity error of less than 2%. Field uniformity can be achieved by superimposing different illumination channels.

[0075] The illumination of the entrance pupil of the projection optics 10 can be geometrically defined by the arrangement of the pupil facets. By selecting the illumination channels, in particular the subset of pupil facets that guide light, the intensity distribution in the entrance pupil of the projection optics 10 can be adjusted. This intensity distribution is also referred to as the illumination setting.

[0076] Another preferred pupil uniformity in the area of ​​defined illuminated sections of an illumination pupil of the illumination optics 4 can be achieved by a redistribution of the illumination channels.

[0077] Further aspects and details of the illumination of the object field 5 and, in particular, the entrance pupil of the projection optics 10 are described below.

[0078] The projection optics 10 can, in particular, have a homocentric entrance pupil. This can be accessible. It can also be inaccessible.

[0079] The entrance pupil of the projection optics 10 cannot always be illuminated exactly by the pupil facet mirror 22. When the projection optics 10 image the center of the pupil facet mirror 22 telecentrically onto the wafer 13, the aperture rays often do not intersect at a single point. However, a surface can be found where the pairwise determined separation of the aperture rays is minimized. This surface represents the entrance pupil or a surface conjugate to it in real space. In particular, this surface exhibits a finite curvature.

[0080] The projection optics may have different entrance pupil positions for the tangential and sagittal beam paths. In this case, an imaging element, in particular an optical component of the transmission optics, should be provided between the second faceted mirror 22 and the reticle 7. This optical element can accommodate the different positions of the tangential and sagittal entrance pupils.

[0081] In the arrangement of the components of the illumination optics 4 shown in Figure 1, the pupil facet mirror 22 is arranged in a plane conjugate to the entrance pupil of the projection optics 10. The field facet mirror 20 is tilted relative to the object plane 6. The first facet mirror 20 is tilted relative to an arrangement plane defined by the deflecting mirror 19. The first facet mirror 20 is tilted relative to an arrangement plane defined by the second facet mirror 22.

[0082] Figure 2 schematically shows in meridional section another projection exposure system 101 for DUV projection lithography, in which the invention can also be applied.

[0083] The construction of the projection exposure system 101 and the principle of the illustration are comparable to the construction and procedure described in Figure 1. Identical components are designated with a reference numeral increased by 100 compared to Figure 1; thus, the reference numerals in Figure 2 begin with 101.

[0084] In contrast to an EUV projection exposure system 1 as described in Figure 1, due to the longer wavelength of the DUV radiation 116 used as useful light in the range of 100 nm to 300 nm, in particular 193 nm, refractive, diffractive and / or reflective optical elements 117, such as lenses, mirrors, prisms, end plates and the like, can be used in the DUV projection exposure system 101 for imaging or illumination.The projection exposure system 101 essentially comprises a lighting system 102, a reticule holder 108 for receiving and precisely positioning a reticule 107 provided with a structure, by which the subsequent structures on a wafer 113 are determined, a wafer holder 114 for holding, moving and precisely positioning this wafer 113 and a projection lens 110, with several optical elements 117, which are held in a lens housing 119 of the projection lens 110 via mounts 118.

[0085] The illumination system 102 provides the DUV radiation 116 required for imaging the reticulum 107 onto the wafer 113. A laser, a plasma source, or the like can be used as the source of this radiation 116. Within the illumination system 102, the radiation 116 is shaped by optical elements such that, upon striking the reticulum 107, the DUV radiation 116 exhibits the desired properties with respect to diameter, polarization, wavefront shape, and the like. The construction of the subsequent projection optics 101 with the lens housing 119 differs in principle from the construction described in Figure 1, except for the additional use of refractive optical elements 117 such as lenses, prisms, and end plates, and is therefore not described further.

[0086] Figure 3 shows a rough schematic representation of a projection exposure system 1 known from the prior art, as explained in Figure 1. The EUV projection exposure system 1 shown in Figure 3 comprises a machine bed 30 and a base frame 31, which is connected to the base frame 31 by a decoupling device 49 to prevent the transmission of mechanical vibrations from the machine bed 30 to the base frame 31. For the sake of simplicity, all decoupling devices 49 listed below, which have no specific significance for the invention, are referred to by the reference numeral 49, whereas relevant decoupling devices are each given a separate reference numeral.

[0087] The base frame 31 is connected via a further decoupling 49 to an intermediate frame 32, on which the projection optics 10 and a reference frame 34 are arranged. The projection optics 10 comprise a module frame 33 for receiving mirror modules 35, the module frame 33 and the reference frame 34 each being connected to the intermediate frame 32 via a decoupling 49. The decoupling 49s thus minimize the transmission of mechanical vibrations to the mirrors arranged on the mirror modules 35.1, 35.2, 35.3, 35.4, 35.5, 35.6 (not specifically labeled in the figure). It is well known to those skilled in the art that the decoupling 49s are not identical, but are each designed to meet the specific requirements placed upon them. The mirror modules 35.1, 35.2, 35.3, 35.4, 35.5, 35.6 are connected to the module frame 33 via connections 36. The mirror modules 35.1, 35.2, 35.3, 35.4, 35.5, 35.6 further include sensors 38 which detect the position of the mirrors relative to the reference frame 34, thereby enabling the position of the individual mirrors relative to each other and to other components of the projection exposure system 1, such as the reticule 7 and the wafer 13 (both not shown) described in Figure 1, to be controlled via a control unit (not shown). In the example shown, the mirror module 35.3 is connected via a line 47 to a control unit 46 for positioning the mirrors. The line 47 has a decoupling loop 44 between the base frame 31 and the intermediate frame 32, between the intermediate frame and the module frame 33, and between the module frame and the mirror module 35.3. These decoupling loops serve to minimize the transmission of mechanical vibrations to the mirror modules 35.1, 35.2, 35.3, 35.4, 35.5, and 35.6.

[0088] The mirror module 35.3 includes, for example, fluid lines 39 for cooling the mirror with a fluid 40, such as pure water. The fluid 40 is supplied from a first section 41.1 of a water cabinet 41, which provides and conditions the fluid 40 and is connected to the base frame 31 and the machine bed 30 via decoupling devices 49, via a supply line 42 to the fluid line 39 of the mirror arranged on the mirror module 35.3, and is then returned via a discharge line 43 to a second section 41.2 of the water cabinet 41, with the two sections 41.1 and 41.2 being connected to each other via a connecting line 45. The supply line 42 and the discharge line 43 each have a decoupling loop 44 between the base frame 31 and the intermediate frame 32, between the intermediate frame and the module frame 33, and between the intermediate frame and the mirror M3, which serves to minimize the transmission of mechanical vibrations to the mirror modules 35.1, 35.2, 35.3, 35.4, 35.5, 35.6. To illustrate the excitation path 48 of the acoustic vibrations from the water cabinet 41 to the mirrors, this is shown as a dashed line in Figure 3, where the points represent positions at which acoustic vibrations can be generated by the transmission of mechanical vibrations to the fluid 40. The supply line 42 and the return line 43 also include both line dampers 50 for damping the mechanical vibrations transmitted via the lines 42, 43, and fluid dampers 60 for damping acoustic vibrations (WLA) transmitted via the fluid 40. These are arranged at different points in the lines 42, 43, partly due to space constraints, which means that an interaction between the mechanical and acoustic vibrations transmitted via the lines 42, 43 and the fluid 40 can occur even downstream of the dampers 50, 60.Figure 4 shows a conduit assembly 70 according to the invention, which can be used in a fluid line 39, 42, 43 as described in Figure 3. The conduit assembly 70 is part of a fluid channel 71 and includes a damping section.

[0089] 72.1, 72.2 damping element, wherein in Figure 4 a first embodiment of the damping section 72.1 is formed in the upper region and a second embodiment of the damping section 72.2 is formed in the lower region. The damping section 72.1, 72.2 is connected at both ends via adapters 74.1, 74.2 to a cable connection 73.1, 73.2, the connection being made by welding, clamping or any other suitable connection technique.

[0090] The damping section 72.1, 72.2 comprises a fluid line section designed as a viscoelastic hose 76, which in the embodiments shown in Figure 4 is connected by a line section 75.1, 75.2 of the damping section

[0091] 72.1, 72.2 is enclosed. In the embodiment shown in the upper part of Figure 4, the conduit section is designed as a flexible corrugated hose 75.1, and in the embodiment shown in the lower part of Figure 4, the conduit section is designed as a pipe 75.2 with a constant diameter, wherein the pipe 75.2, in contrast to the corrugated hose 75.1, is rigid. The fluid 79 of the fluid channel 71 flows through the viscoelastic hose 76, wherein the adapters

[0092] 74.1 , 74.2 ensure that no fluid 79 enters the primary volume formed between the viscoelastic hose 76 and the pipe section 75.1 , 75.2

[0093] 77.1, 77.2 of the damping section 72.1, 72.2 or into the vicinity of the damping section 72.1, 72.2. The primary volume 77.1, 77.2 is, as explained above, defined as a spatial region whose volume is independent of the deformation of the viscoelastic tube 76.

[0094] In the case of a pipe section designed as a flexible corrugated hose 75.1, the damping section 72.1, due to its radially elastic properties (i.e., perpendicular to the flow direction), can serve to compensate for tolerances between components connected by the pipe assembly 70 or between other interfaces of the fluid piping system connected to the pipe assembly 70. The flow direction is shown as an arrow in Figure 4. Furthermore, a pipe section can also comprise a combination of a corrugated hose 75.1 and a pipe 75.2.

[0095] According to the invention, the damping sections 72.1, 72.2 comprise secondary volumes 78.1, 78.2, which, in the embodiments shown in Figure 4 (upper and lower regions of Figure 4), are arranged within the primary volumes 77.1, 77.2 of the damping sections 72.1, 72.2. The primary volumes 77.1, 77.2 are defined by the outer circumference of the viscoelastic hose 76 and the inner diameter of the corrugated hose 75.1 or the tube 75.2, respectively.

[0096] In the damping section 72.1 with the corrugated hose 75.1, the primary volume

[0097] 77.1 is divided into a secondary volume 78.1 and a sacrificial volume 81.1 by a separating element designed as a separating film 80. The sacrificial volume 81.1 is filled over time with the fluid 79 diffusing through the viscoelastic tube 76. Due to the incompressibility of the fluid 79, the sacrificial volume 81.1 can no longer be used for the expansion of the tube 76 into the sacrificial volume 81.1. The secondary volume 78.1 is separated from the sacrificial volume by the separating film 80.

[0098] 81.1 separated. The separating film 80 comprises a material that is impermeable to the fluid 79 or a material that, even over a very long period, such as 10 years, allows only a negligible amount of fluid 79 to permeate into the secondary volume 78.1, less than 5% of the secondary volume 78.1. The material can be, for example, metallized PET film or PCTE film, to name just two possible examples. Alternatively, other metallically coated or otherwise metallized films, as well as metallic films such as aluminum foil, can be used.

[0099] In the embodiment of the damping section 72.2 with the tube 75.2 shown below in Figure 4, the secondary volume 78.2 is formed in a separating element designed as a composite element 82. The secondary volume 78.2 is subdivided into a plurality of partial volumes 78.2x, some of which are designated by reference numerals 78.21, 78.22, and 78.23 in Figure 4. The partial volumes 78.2x are all arranged in the composite element 82, which in the embodiment shown in Figure 4 is designed as an aluminum-coated bubble wrap. If the sacrificial volume 81.2, which in this embodiment corresponds to the primary volume 77.2 remaining after subtracting the secondary volume 78.2, fills with the fluid 79 over time, the viscoelastic hose 76 can expand due to compression of the secondary volumes 78.2x.The expansion is further enhanced by the fact that the damping of the acoustic vibrations present in the fluid 79 remains advantageously ensured. The composite element 82 can comprise the same materials or material combinations described above for the separating film 80.

[0100] The composite element 82 can be partially connected to the adapters 74.1, 74.2, as shown in Figure 4, or alternatively arranged as a freely movable element or as a film divided into several elements within the primary volume 77.2. By partially connecting the elements, the volumes shown above and below the composite element 82 in Figure 4 are connected to each other, so that together they form the sacrificial volume 81.2.

[0101] Alternatively, the composite element 82 can also have only one continuous secondary volume 78.2, which is either also partially connected to the adapters 74.1, 74.2 or can be freely arranged within the primary volume 77.2 without fixation. Furthermore, the secondary volume 78.2 can also have several unconnected sub-secondary volumes 78.2x, which can also be arranged within the primary volume 77.2 either with or without fixation, i.e., freely.

[0102] Both embodiments of the secondary volume 78.1, 78.2 ensure that at least 1%, preferably 10%, and particularly preferably 50% of the primary volume 77.1, 77.2 cannot be filled by the fluid 79 that diffuses into the sacrificial volume 81.1, 81.2 due to the permeability of the viscoelastic tube 76, wherein the period until the sacrificial volume 81.1, 81.2 is filled with fluid 79 should be 10 years, preferably 20 years, and particularly preferably 50 years. This ensures the dynamic, elastic deformation of the viscoelastic tube 76, necessary for the viscoelastic damping of acoustic vibrations in the fluid 79, by the remaining secondary volume 78.1, 78.2 filled with a compressible medium, over a long period of time. It is clear to the person skilled in the art that each of the illustrated embodiments of a primary volume 77.1 , 77.2 , sacrificial volume 81 .1 , 81.2 and of a secondary volume 78.1 , 78.2, as well as their division into one or more volumes and the arrangement of the secondary volumes 78.1 , 78.2 in the primary volumes 77.1 , 77.2 and the design of the conduit sections 75.1 , 75.2 can be combined arbitrarily.

[0103] Figure 5 shows a further embodiment of a conduit assembly 90 according to the invention, which can be used in a fluid line 39, 42, 43 as described in Figure 3. The conduit assembly 90 is part of a fluid channel 91 and comprises a rigid tube 96 made of a fluid-impermeable material. The tube 96 is connected to a conduit connection 93 via a flange 94. The conduit assembly 90 can be connected to a fluid piping system, as illustrated by way of example in Figure 3, via the conduit connection 93.

[0104] The conduit assembly 90 further comprises a damping element designed as an absorber 92. In the embodiment shown in Figure 5, the absorber 92 is arranged in the fluid channel 91 and is thus surrounded by the fluid 79. The absorber 92 dampens the acoustic vibrations present in the fluid 79, the damping principle corresponding to that of the viscoelastic hose 76 (Figure 4).

[0105] The absorber 92 has a body 99 connected to the pipe 96 via connections 100, wherein the body 99 and the connections 100 are designed such that any disturbance of the fluid flow is minimized. The boundary of the absorber 92, designed as body 99, is elastic and encloses a primary volume 97 necessary for the viscoelastic deformation of the body 99. In Figure 5, the primary volume 97 is defined by the area of ​​the undeformed body 99, partially represented by dashed lines. Within the body 99, a secondary volume 98, enclosed by a separating element designed as a film 95, is arranged as part of the primary volume 97, the uncompressed state of the secondary volume 98 being represented by dashed lines in Figure 5.As already explained in Figure 4, the foil 95 (BZ 80 in Figure 4) is designed such that permeation of the fluid 79 into the secondary volume 98 is excluded or only reaches a significant extent after a very long period of time. The sacrificial volume 81.1 explained in Figure 4.

[0106] 81.2, i.e. the volume filled over time by permeation with the fluid 79, corresponds in turn to the portion of the primary volume 97 remaining after subtraction of the secondary volume 98, i.e. the area shown in dashed lines in Figure 5 within the body 99.

[0107] Alternatively, one or more absorber bodies 99 can also be arranged in one of the primary volumes 77.1 , 77.2 described in Figure 4 and, in the case of several absorber bodies 99, can be introduced there, for example, as loose bulk material.

[0108] In all embodiments, the secondary volumes 78.1, 78.2, 98 are protected from significant permeation of the fluid into the respective secondary volumes 78.1, 78.2, 98 by suitable separating elements 80, 82, 95. The secondary volumes 78.1,

[0109] As explained above, the secondary volumes 78.1, 78.2, and 98 fill by a maximum of 5% of their respective volumes over a period of 10 years, so that 95% of the secondary volumes 78.1, 78.2, and 98 remain available. This ensures that deformation of the viscoelastic tube 76 and the absorber body 99 is guaranteed for a sufficiently long period.

[0110] The permeation of the gas present in the primary volumes 77.1, 77.2, 97 and / or secondary volumes 78.1, 78.2, 98 into the fluid line 71, 91 can be advantageously reduced by using a gas with a lower permeability than the commonly used air under the given circumstances. These gases or gas mixtures can include, for example, alkanes (methane, ethane, propane, butane, isobutane), noble gases (helium, neon, argon, krypton, xenon), or fluorinated gases (SF6, CF4, C5-FN, C4-FN), as well as all fluorinated refrigerants. Reference numeral list

[0111] 1 projection monitoring system

[0112] 2 Lighting system

[0113] 3. Radiation source

[0114] 4 Lighting optics

[0115] 5 object field

[0116] 6 Object level

[0117] 7 reticles

[0118] 8 label holders

[0119] 9 Reticle displacement drive

[0120] 10 Projection optics

[0121] 11 Image field

[0122] 12 Image plane

[0123] 13 wafers

[0124] 14 wafer holders

[0125] 15 wafer transfer drive

[0126] 16 EUV radiation

[0127] 17 Collector

[0128] 18 Intermediate focus plane

[0129] 19 deflecting mirrors

[0130] 20 faceted mirrors

[0131] 21 facets

[0132] 22 faceted mirrors

[0133] 23 facets

[0134] 30 machine bed

[0135] 31 Basic frame

[0136] 32 intermediate frames

[0137] 33 module frames

[0138] 34 Reference framework

[0139] 35 Mirror module connection mirror

[0140] sensor

[0141] Fluid line

[0142] Fluid, 41.1, 41.2 Water Cabinet

[0143] supply line

[0144] Derivation

[0145] Decoupling loop fluid line

[0146] Connecting line to fluid reservoir

[0147] Decoupling in general

[0148] Line damper

[0149] Fluid damper

[0150] Cable assembly

[0151] Fluid channel .1 , 72.2 Damping section (damping element).1 ,73.2 Line connections .1 ,74.2 Connection adapter .1 ,75.2 Corrugated hose, pipe (line section)

[0152] Viscoelastic tube (fluid line).1 ,77.2 Primary volume .1 ,78.2,78.2x Secondary volume

[0153] Fluid

[0154] Separating foil (separating element) .1 ,81.2 Sacrificial volume

[0155] Composite element (composite element)

[0156] Cable assembly

[0157] Fluid channel

[0158] Absorber (damping element)

[0159] Line connection

[0160] flange

[0161] Foil (separating element) 96 Pipe (fluid line)

[0162] 97 Primary volumes

[0163] 98 Secondary volumes

[0164] 99 Body Absorbers

[0165] 100 Absorber connection

[0166] 101 Projection exposure system

[0167] 102 Lighting system

[0168] 107 reticles

[0169] 108 label holders

[0170] 110 Projection optics

[0171] 113 wafers

[0172] 114 wafer holders

[0173] 116 DUV radiation

[0174] 117 optical element

[0175] 118 versions

[0176] 119 lens bodies

[0177] M1-M6 mirrors

Claims

Patent claims 1. Pipe assembly (70,90) for a fluid line (39,42,43) for a system (1 ,101 ) for semiconductor technology with at least one damping element (72.1 ,72.2,92) for damping acoustic vibrations in the fluid (79), wherein the line assembly (70,90) has a compressible primary volume (77.1.77.2.97) has, into which the damping element (72.1 ,72.2,92) moves at least section by section when the same is deformed, characterized in that the conduit assembly (70,90) has a compressible secondary volume (78.1.78.2.98) exhibits, which is part of the primary volume (77.1 ,77.2,97) is formed, wherein the secondary volume (78.1 ,78.2,98) is at least partially separated from the primary volume by a separating element (80,82,99). (77.1 ,77.2,97) is separated.

2. Conduit assembly (70, 90) according to claim 1, characterized in that the proportion of the secondary volume (78.1, 78.2, 98) to the primary volume (77.1 ,77.2,97) at least 1%, preferably at least 10%, particularly preferably at least 50% of the.

3. Conductor assembly (70, 90) according to one of claims 1 or 2, characterized in that the damping element (72.1 , 72.2, 92) comprises a viscoelastic material.

4. Conduit assembly (70, 90) according to one of the preceding claims, characterized in that the stiffness of the secondary volume (78.1 , 78.2, 98) is at least a factor of 5-5000 smaller, preferably at least a factor of 5-500 smaller, particularly preferably at least a factor of 5-100 smaller, compared to the stiffness of the damping element (72.1 , 72.2, 92).

5. Conduit assembly (70, 90) according to one of the preceding claims, characterized in that a limitation (80, 82, 99) of the secondary volume (78.1, 78.2, 98) is reduced by a factor of 2, preferably by a factor of 100, particularly preferably by a factor of 100, compared to a limitation of the damping element (72.1, 72.2, 92). - 28 - tor 1000 has a lower permeation coefficient.

6. Conduit assembly (70, 90) according to one of the preceding claims, characterized in that the secondary volume (78.1, 98) is designed as a continuous volume.

7. Conduit assembly (70, 90) according to one of claims 1 to 5, characterized in that the secondary volume (78.2) has at least two partial volumes (78.21, 78.22, 78.23, 78.2x).

8. Conduit assembly (70, 90) according to one of the preceding claims, characterized in that the secondary volume (78.1 , 78.2) is freely movable within the primary volume (77.1 , 77.2).

9. Conduit assembly (70, 90) according to one of the preceding claims, characterized in that the secondary volume (78.1 , 78.2, 98) is filled with a compressible substance or mixture of substances.

10. Conduit assembly (70, 90) according to claim 9, characterized in that the material is at least partially designed as a compressible fluid.

11. Conduit assembly (70, 90) according to claim 10, characterized in that the fluid comprises one of the following fluids: Dry air, extremely dry clean air, nitrogen, oxygen, carbon dioxide, alkanes (methane, ethane, propane, butane, isobutane), noble gases (helium, neon, argon, krypton, xenon) or fluorinated gases and fluorinated refrigerants.

12. Conductor assembly (70, 90) according to claim 9, characterized in that the material is at least partially designed as a compressible foam. is.

13. Conductor assembly (70, 90) according to claim 12, characterized in that the foam comprises one of the following materials: Polyurethane (PUR / PU) - soft foam, acrylonitrile butadiene rubber (NBR), fluororubber (FKM), perfluororubber (FFKM), polyethylene (PE), silicone foam, polystyrene foams (such as PS-E, XPS), polyphenylene ether (PP-E) and polyvinyl chloride (PVC-E), sponge rubber or moss rubber.

14. Conductor assembly (70, 90) according to one of the preceding claims, characterized in that the separating element is designed as a film (80, 82, 95).

15. Conductor assembly (70, 90) according to claim 14, characterized in that the foil (80, 82, 95) comprises aluminium, in particular is coated with aluminium at least in sections.

16. Conduit assembly (70, 90) according to one of the preceding claims, characterized in that a fluid arranged in the primary volume (77.1 , 77.2, 97) and / or secondary volume (78.1 , 78.2, 98) has a permeability into the fluid (79) that is 25 times smaller, preferably 50 times smaller and particularly preferably 100 times smaller than that of air.

17. Conduit assembly (70, 90) according to claim 16, characterized in that the fluid may comprise a gas or a gas mixture from the following list: Tetrafluoromethane (CF4), alkanes (methane, ethane, propane, butane, isobutane), noble gases (helium, neon, argon, krypton, xenon) or fluorinated gases, such as SF6, C5-FN, C4-FN, and all fluorinated refrigerants.

18. System (1 ,101 ) for semiconductor technology comprising a conductor assembly (70,90) according to one of the preceding claims.

19. Plant (1 ,101 ) according to claim 18, characterized in that the plant is designed as a wafer inspection plant, a reticle inspection plant, a reticle repair plant or a projection exposure plant (1 ,101).

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