Workpiece for a semiconductor technology system, system for semiconductor technology, method for producing a workpiece

Abstract

The invention relates to a thermalisation plate (30) for a semiconductor technology system (1, 101), having at least two thermalisation plate elements (40, 41, 50, 51, 52), the thermalisation plate (30) being distinguished in that at least one thermalisation plate element (40, 41) is produced using an additive production method. The invention further relates to a system (1, 101) for semiconductor technology, in particular a projection exposure system (1, 101). The invention further relates to a method for producing a thermalisation plate (30) for a semiconductor technology system (1, 101), having at least two interconnected thermalisation plate elements (40, 41, 50, 51, 52), at least one thermalisation plate element (40, 41) being produced using an additive production method. The method comprises the following method steps: - producing at least one thermalisation plate element (40, 41) using an additive production method, and - joining the thermalisation plate elements (40, 41, 50, 51, 52) by laser welding.

Description

[0001] workpiece for a semiconductor technology system, semiconductor technology system, process for manufacturing a workpiece

[0002] This patent application claims priority over German patent application DE 10 2024 121 164.4, filed on 25.07.2024, the contents of which are incorporated herein in full by reference.

[0003] The invention relates to a thermalization plate for a semiconductor technology system, a semiconductor technology system, in particular a projection exposure system, wafer inspection system or mask inspection system, and a method for manufacturing a thermalization plate.

[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 technology. Current systems of this kind feature fluid-flow thermalization systems for the thermal stabilization of the optics and structures used, which can include both cooling and targeted heating of the optics and structures, depending on location and time.

[0005] Due to its high heat capacity and availability, highly purified water is usually used as the fluid; however, other fluids are also conceivable.

[0006] Thermal insulation plates are used specifically for the thermalization of structures. These plates, acting as surface coolers, typically feature a fluid-flowing cavity supported by struts and columns. The outer contours of the structures to be thermalized are often curved, necessitating that the thermal insulation plates also have a curved outer contour to maintain a uniform distance from the structures. These plates are typically between 6 mm and 6.5 mm thick, with a cavity height ranging from 1.4 mm to 2.2 mm.

[0007] Using a method known from the prior art, flat thermal insulation plates are first produced, whereby the contour of the future cavity is initially milled from a base plate. To form the cavity, the contour is closed with a cover plate. To connect and stabilize the cover plate, the base plate has, on the one hand, an edge that defines the cavity on the outside, and on the other hand, webs and columns remain within the cavity to support the cover plate against deformation.

[0008] The cover plate is welded to the base plate, the edge and the struts with a linear weld, and to the columns with spot, circular or coil welds.

[0009] The curved shape of the thermal insulation sheets is produced by bending the flat thermal insulation sheets. To prevent cavity collapse, i.e., the partial collapse of the cavity during bending, the flat thermal insulation sheet is filled with water and cooled until the water freezes. The bending is therefore carried out in the frozen state.

[0010] This method has the disadvantage that the frozen water is insufficient to prevent cavity collapse. Furthermore, not only is the actual filling process prone to errors, but the bending process itself is also time-limited due to the potential thawing of the filling material and is subject to an additional potential defect. Additionally, the bent thermalization sheet does not meet the previously defined tolerances for the dimensional accuracy of the sheet edges, or only after a subsequent, time-consuming, and therefore costly straightening process.

[0011] The object of the present invention is to provide a device for eliminating the disadvantages of the prior art explained above. Furthermore, the object of the invention is to provide a method for manufacturing a thermalization plate. This object is achieved by a device and a method with the features of the independent claims. The dependent claims relate to advantageous embodiments and variants of the invention.

[0012] A thermalization plate according to the invention for a semiconductor technology system with at least two interconnected thermalization plate elements comprises, according to the invention, at least one thermalization plate element produced by an additive manufacturing process.

[0013] In particular, the thermalization sheet element produced by an additive manufacturing process can be designed as an arc element. The second thermalization sheet element, on the other hand, can be designed as a flat plate element and produced using a conventional manufacturing process.

[0014] Furthermore, the thermal insulation plate can have at least one cavity for receiving a fluid. This cavity can, for example, include ribs and columns for stabilization, which are arranged within the cavity.

[0015] In particular, at least one cavity can be designed as a fluid channel. A fluid channel is characterized by its comparatively small dimensions, which can, for example, have a circular or rectangular geometry and are suitable for local thermalization.

[0016] In a further embodiment of the invention, the at least two thermalization sheet elements can be joined together by laser welding. Laser welding has the advantage of allowing for a precisely controllable and significantly more localized energy input than an arc welding process. Focusing the laser beam enables, in particular, increased energy input within the material's lattice structure, i.e., in a range of 0.1 mm to 3 mm within the material. This allows, for example, the heat input to be applied precisely at the contact surface when thermalization sheet elements are arranged in an overlapping configuration. This makes it possible to create a weld seam, especially a so-called I-seam with a nearly parallel cross-section. The main advantages resulting from this for the specific application are a low-distortion joint and a high surface quality of the weld seam.With slightly increased equipment costs, very good results could also be expected with friction stir welding. Arc welding processes would also be applicable, accepting slight reductions in quality.

[0017] In a further embodiment of the invention, the arc element can have at least one flat section corresponding to the plate element. This can advantageously simplify alignment and joining by means of the flat supports directly adjacent to the contact surfaces, or enable higher accuracy in the alignment of the two thermalization sheet elements before welding.

[0018] Furthermore, the thermal insulation plate can include a device for aligning the thermal insulation plate elements relative to each other before joining. When aligning the two thermal insulation plate elements, it is particularly important to align them along the longitudinal direction of the common contact surface in order to avoid or reduce edges at the perimeter of the cavity, especially in the case of a cavity designed as a fluid channel. This reduces or completely eliminates flow disturbances. The remaining degrees of freedom for alignment are already sufficiently ensured by a common mounting of the thermal insulation plate elements, for example on their underside, and the common contact surface.

[0019] In particular, the device can have at least one first tooth and at least one second tooth corresponding to the first. These teeth can, in addition to the alignment along the contact surface described above, also establish or at least ensure contact or a desired distance between the contact surfaces. Alternatively, the alignment of the thermalization sheet elements relative to each other can also be achieved by an external device before joining.

[0020] In a further embodiment of the invention, the thermalization plate can have a compressive strength in the range of 30 to 50 bar, preferably in the range of 50 to 100 bar, and particularly preferably even higher. Furthermore, the thermalization plate can have a positional tolerance of the plate edges of less than 1 mm, preferably less than 0.7 mm, and particularly preferably less than 0.4 mm.

[0021] In addition, the thermalizing plate can have a cavity depth of less than 0.4 mm, preferably less than 0.25 mm, particularly preferably less than 0.05 mm.

[0022] In particular, the thermalizing plate can have a surface roughness in the cavity of less than Ra 3.2, preferably less than Ra 2.0.

[0023] Furthermore, the thickness of the thermal insulation plate can be less than 8 mm, preferably less than 6 mm, and particularly preferably less than 4 mm. The thickness of the thermal insulation plates depends solely on the thickness of the base plates and cover plates, which may be determined by application constraints. These constraints may include, for example, compressive strength or corrosion resistance against the cooling medium.

[0024] In particular, the cavities can have a height greater than 1 mm, preferably greater than 3 mm, and most preferably greater than 5 mm. The cavities are produced, as explained above, by milling out the base plates, so that the height of the cavities, for a given thickness of the thermal insulation plate, is determined by the remaining wall thickness at the bottom of the cavity in the base plate and the thickness of the cover plate.

[0025] As already mentioned, the proposed solutions are particularly suitable for semiconductor technology systems such as projection exposure systems, wafer inspection systems or mask inspection systems.

[0026] A method according to the invention for producing a thermalization sheet as described above comprises the following process steps:

[0027] - Production of at least one of the thermalization sheet elements using an additive manufacturing process. - Joining of the elements by laser welding, friction stir welding or arc welding.

[0028] The additive manufacturing process makes it possible to produce curved elements and basically almost all contours, both with regard to the outer geometry and the inner geometry of the thermalization sheet element, which can have a positive effect on the achievable accuracies and the manufacturing costs.

[0029] Exemplary embodiments and variants of the invention are explained in more detail below with reference to the drawing. The drawing shows

[0030] Figure 1 schematically shows a projection exposure system for EUV projection lithography in meridional section.

[0031] Figure 2 schematically shows a projection exposure system for DUV projection lithography in meridional section.

[0032] Figure 3 shows an embodiment of the invention,

[0033] Figure 4 shows a detail of the invention, and

[0034] Figure 5 shows a flowchart of a possible manufacturing process.

[0035] The following section describes, with reference to Figure 1, the essential components of a projection exposure system 1 for microlithography in which the invention can be applied. The description of the basic structure of the projection exposure system 1 and its components is not intended to be restrictive.

[0036] 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. A reticle 7 arranged in the object field 5 is illuminated. The reticle 7 is held by a reticle holder 8. The reticle holder 8 can be moved, in particular in a scanning direction, by means of a reticle displacement drive 9.

[0037] 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.

[0038] 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.

[0039] 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.

[0040] Radiation source 3 is an EUV radiation source. Radiation source 3 emits, in particular, 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). The illumination radiation 16 emitted by 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 illuminating 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.

[0041] 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.

[0042] 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.

[0043] The first facets 21 can be configured as macroscopic facets, in particular as rectangular facets or as facets with an arcuate or semicircular edge contour. The first facets 21 can be configured as planar facets or alternatively as convexly or concavely curved facets. As is known, for example, from DE 10 2008 009 600 A1, the first facets 21 themselves can each also be composed of a plurality of individual mirrors, in particular a plurality of micromirrors. The first facet mirror 20 can in particular be configured as a microelectromechanical system (MEMS system). For details, reference is made to DE 10 2008 009 600 A1.

[0044] Between the collector 17 and the deflecting mirror 19, the illumination radiation 16 runs horizontally, i.e. along the y-direction.

[0045] 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.

[0046] 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.

[0047] 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.

[0048] The second facets 23 can have planar or alternatively convex or concave curved reflective surfaces.

[0049] The illumination optics 4 thus form a double-faceted system. This basic principle is also known as a honeycomb condenser (Fly's Eye Integrator).

[0050] 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 side of the projection optics 10, as described, for example, in DE 10 2017 220 586 A1.

[0051] 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.

[0052] 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).

[0053] 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.

[0054] In a further embodiment of the lighting optics 4, the deflecting mirror 19 can also be omitted, so that the lighting optics 4 after the collector 17 can then have exactly two mirrors, namely the first faceted mirror 20 and the second faceted mirror 22.

[0055] The mapping 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 mapping.

[0056] 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 unit 1. 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 that is greater than 0.5 and can also be greater than 0.6, for example, 0.7 or 0.75.

[0057] 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.

[0058] 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.

[0059] 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 value for the image scale β indicates an image with image inversion.

[0060] 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 .

[0061] The projection optics 10 result in a reduction of 8:1 in the y-direction, i.e., in the scan direction. Other magnification ratios are also possible. Magnification ratios with the same sign and absolute values ​​in the x- and y-directions are also possible, for example with absolute values ​​of 0.125 or 0.25.

[0062] 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.

[0063] 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.

[0064] The field facets 21 are each superimposed on the reticulum 7 by an associated pupil facet 23 to illuminate the object field 5.

[0065] 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.

[0066] 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.

[0067] 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.

[0068] Further aspects and details of the illumination of the object field 5, and in particular of the entrance pupil of the projection optics 10, are described below. The projection optics 10 may, in particular, have a homocentric entrance pupil. This may be accessible. It may also be inaccessible.

[0069] The entrance pupil of the projection optics 10 cannot be precisely illuminated 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.

[0070] 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.

[0071] 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 arranged tilted relative to the object plane 6. The first facet mirror 20 is arranged tilted relative to an arrangement plane defined by the deflecting mirror 19.

[0072] The first faceted mirror 20 is arranged at an angle to an arrangement plane defined by the second faceted mirror 22.

[0073] Figure 2 schematically shows in meridional section another projection exposure system 101 for DUV projection lithography, in which the invention can also be applied.

[0074] 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.

[0075] 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.

[0076] The illumination system 102 provides DUV radiation 116 required for imaging the reticulum 107 on the wafer 113. A laser, a plasma source, or the like can be used as the source for this radiation 116. In 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.

[0077] The construction of the following 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, end plates, and is therefore not described further.

[0078] Figure 3 shows an embodiment of a thermalization plate 30 according to the invention, which is depicted in an already assembled state. The thermalization plate 30 has a cavity 31 which, during operation of a projection exposure system 1 described in Figure 1, receives a fluid for thermalization or is filled with a fluid.

[0079] The thermalization plate 30 has two thermalization plate elements designed as arc elements 40, 41 and three as plate elements 50, 51, 52, which are connected to each other at their contact surfaces 60.1, 60.2, 60.3, 60.4 by a weld seam designed as a line seam 61, which is shown only in sections in Figure 3 for the sake of clarity, with the three points adjoining each side intended to illustrate the continuation of the weld seam.

[0080] The plate elements 50, 51, 52, which are flat in the embodiment shown in Figure 3, can be manufactured using a method known from the prior art. The partial areas 31.1, 31.3, 31.5 of the cavity 31 in the embodiment shown in Figure 3 are formed from a base plate.

[0081] 32.1 , 32.2 , 32.3 milled contours 33.1 , 33.2 , 33.3 and a cover plate 34.1 ,

[0082] 34.2, 34.3. The cover plates 34.1, 34.2, 34.3 are welded on one side to an edge 35.1, 35.21, 35.22, 35.3 which defines the contours 33.1, 33.2, 33.3 to the outside, and on the other side to webs 36 and columns 37 remaining within the inner contour of the cavity 31. A laser welding process is used for welding, wherein the edges 35.1, 35.21, 35.22, 35.3 and the struts 36 are welded with a weld seam designed as a line weld 61, and the columns 37 with a weld seam designed as a spot, loop, or circular weld 62, which are shown with a reference numeral in Figure 3 only as an example.

[0083] The arc elements 40, 41 are manufactured by an additive manufacturing process, in particular by selective laser melting, so that in the sub-areas 31.2, 31.4 of the cavity 31 the webs 36 and the columns 37 are already integrally manufactured when printing the arc elements 40, 41.

[0084] The plate elements 50, 51, 52 and the arc elements 40, 41 are aligned to each other by means of toothing 65.1, 65.2, so that the individual sub-areas 31.1, 31.2, 31.3, 31.4, 31.5 of the cavity 31 can be joined without steps or edges at the transition between the elements 40, 41, 50, 51, 52 at their contact surfaces 60.1, 60.2, 60.3, 60.4.

[0085] After joining the five elements 40, 41, 50, 51, 52 by means of welds formed as line welds 61, the thermalization plate 30 is additionally welded around its perimeter 35, i.e., an additional perimeter weld formed as a fillet weld 63 is applied laterally, which is intended to further ensure the tightness in the edge area. The fillet weld 63 is shown only partially in Figure 3, with the three points on each side illustrating the continuation of the weld. In the area of ​​the thermalization plate elements 40, 41 produced by additive manufacturing, the fillet weld 63 is not necessary due to the closed edge 35.2, 35.4 of the thermalization plate elements 40, 41.

[0086] Figure 4 shows a detail of the invention, in which a device designed as a toothing 65.2 for aligning the arc element 41 with the two adjacent plate elements 51, 52 is depicted. The toothing 65.2 has one tooth 66.1, 66.2 on each of the arc element 41 and one corresponding tooth 67.1, 67.2 on each of the plate elements 51, 52. The toothing 65.2 further has guide surfaces 68.11, 68.12, 68.21, 68.22 on the plate elements 51, 52, which ensure the meshing of the teeth 66.1, 66.2, 67.1, 67.2. All degrees of freedom are defined by the toothing 65.2, the contact surfaces 64.3, 64.4 and a device for aligning the height, i.e. in the thickness direction of the plate elements 51, 52 or the arc element 41, which is not shown in Figure 4.This ensures that the plate elements 51, 52 and the arc element 41 can be joined without or only within the range of permissible deviations of less than 0.3 mm, preferably less than 0.1 mm, and particularly preferably less than 0.05 mm.

[0087] The thermalizing plate 30 according to the invention, as described in Figures 3 and 4, has at least the following features.

[0088] A compressive strength against bursting of 30-50 bar, preferably 50-100 bar, particularly preferably over 100 bar. A dimensional accuracy of the positional tolerance of the sheet edges in space of less than 1 mm, preferably less than 0.7 mm, particularly preferably less than 0.4 mm.

[0089] A dimensional accuracy of the plane tolerance of the outer surfaces of the thermalizing plate of less than 1.5 mm, preferably less than 1 mm, particularly preferably less than 0.7 mm.

[0090] A cavity dip of less than 0.4 mm, preferably less than 0.25 mm, particularly preferably a cavity dip that is not detectable with conventional measuring instruments.

[0091] A tightness test performed with helium, where the tightness is determined by a maximum leak rate of less than 1 * 10 A -9 mbar*l / s is specified.

[0092] A surface roughness on the outer surfaces of the thermalizing plate of less than Ra 0.8.

[0093] A surface roughness in the cavity of the thermalizing plate of less than Ra 3.2, preferably less than Ra 2.0.

[0094] Figure 5 shows a manufacturing process according to the invention for producing a thermalization sheet 30 for a system 1 , 101 of semiconductor technology, with at least two interconnected thermalization sheet elements 40, 41 , 42, 50, 51 , wherein at least one thermalization sheet element 40, 41 is produced using an additive manufacturing process.

[0095] In a first process line 70 with the process steps 71 , 72, 73, 74 explained in more detail below, a thermalization sheet element designed as a flat plate element 50, 51 , 52 is manufactured in a conventional manner.

[0096] After cutting 71 from a base plate 32.1, 32.2, 32.3 and milling 72 a partial area 31.1, 31.3, 31.5 of the future cavity 31, the base plate 32.1, 32.2, 32.3 is welded in a further step 73 to a corresponding cover plate 34.1, 34.2, 34.3 to form a plate element 50, 51, 52. In a fourth optional process step 74, the plate element 50, 51, 52 is straightened, for example by roll straightening, so that it meets the required flatness.

[0097] In a second process stream 80, which can be carried out in parallel to the first process stream 70, a thermalization sheet element designed as an arc element 40, 41 is produced in a first process step 81 by an additive manufacturing process, such as selective laser melting in a powder bed. In a subsequent second process step 82, the arc element 40, 41 is post-processed, in particular the internal surfaces are refined, for example by ionization, and the surface roughness on the outside of the arc elements 40, 41 is improved.

[0098] In the third process line 90, the two thermalization sheet elements 40, 41, 50, 51, 52 are joined in a first process step 91 and subjected to a final inspection in a second process step 92.

[0099] Reference symbol list

[0100] 1 projection monitoring system

[0101] 2 Lighting system

[0102] 3. Radiation source

[0103] 4 Lighting optics

[0104] 5 object field

[0105] 6 Object level

[0106] 7 reticles

[0107] 8 label holders

[0108] 9 Reticle displacement drive

[0109] 10 Projection optics

[0110] 11 Image field

[0111] 12 Image plane

[0112] 13 wafers

[0113] 14 wafer holders

[0114] 15 wafer transfer drive

[0115] 16 EUV radiation

[0116] 17 Collector

[0117] 18 Intermediate focus plane

[0118] 19 deflecting mirrors

[0119] 20 faceted mirrors

[0120] 21 facets

[0121] 22 faceted mirrors

[0122] 23 facets

[0123] 30 Thermal insulation plates

[0124] 31.31.1 -31.5 Cavity, partial cavity

[0125] 32.1-32.3 Base plates

[0126] 33.1-33.3 Recesses in the base plates

[0127] 34.1-34.3 Cover plates

[0128] 35.35.1 -35.3 Edge Bridge

[0129] column

[0130] Outer contour of the finished thermal insulation sheet

[0131] arch element

[0132] arch element

[0133] Panel element

[0134] Panel element

[0135] Plate element contact surfaces

[0136] Line seam (weld seam)

[0137] Spot weld, ring weld or coil weld (weld weld)

[0138] Fillet weld, toothing, tooth, arc element, tooth, plate element, guide surfaces

[0139] Process chain first thermalization sheet element

[0140] Process step 1: Plate elements

[0141] Process step 2: Plate elements

[0142] Process step 3: Plate elements

[0143] Process step 4: Plate elements

[0144] Process chain first thermalization sheet element

[0145] Process step 1: Bow elements

[0146] Process step 2: Bow elements

[0147] Process chain: Joining the thermalization sheet elements

[0148] Process step 1 Joining

[0149] Process step 2 Joining

[0150] Projection exposure system 102 Lighting system

[0151] 107 reticles

[0152] 108 label holders

[0153] 110 Projection optics

[0154] 113 wafers

[0155] 114 wafer holders

[0156] 116 DUV radiation

[0157] 117 optical element

[0158] 118 versions

[0159] 119 lens bodies

[0160] M1-M6 mirrors

Claims

Patent claims 1. Thermalization plate (30) for a system (1, 101) of semiconductor technology with at least two thermalization plate elements (40, 41, 50, 51, 52), wherein at least one thermalization plate element (40, 41) is manufactured using an additive manufacturing process, characterized in that the thermalization plate (30) has at least one cavity (31) for receiving a fluid, wherein the thermalization plate (30) has a surface roughness in the cavity of less than Ra 3.2, preferably less than Ra 2.

0.

2. Thermalization plate (30) according to claim 1 , characterized in that the thermalization plate element (40,41 ) produced by an additive manufacturing process is designed as an arc element (40,41 ).

3. Thermalization plate (30) according to one of claims 1 or 2, characterized in that at least one cavity is designed as a temperature control channel.

4. Thermalization plate (30) according to one of the preceding claims, characterized in that the at least two thermalization plate elements (40, 41, 50, 51, 52) are joined together by laser welding, friction stir welding or arc welding.

5. Thermalization plate (30) according to one of claims 2 to 4, characterized in that the arc element (40,41 ) has at least one planar section corresponding to the plate element (50,51 ,52).

6. Thermalization plate (30) according to one of the preceding claims, characterized in that the thermalization plate (30) has a device (65.1, 65.2) for alignment the thermalization sheet elements (40,41 ,50,51 ,52) to each other before joining.

7. Thermalization plate (30) according to claim 6, characterized in that the device (65.1 ,65.2) has at least one first tooth (67.1 ,67.2) and at least one second tooth corresponding to the first (68.1 ,68.2).

8. Thermalization plate (30) according to claim 7, characterized in that the teeth (67.1 ,67.2,68.1 ,68.2) are arranged such that they at least align the thermalization plate elements (40,41 ,50,51 ,52) along the longitudinal orientation of a common contact surface (60.1 ,60.2,60.3,60.4) ensure.

9. Thermalization plate (30) according to one of the preceding claims, characterized in that the thermalization plate (30) has a compressive strength in the range of 30 to 50 bar, preferably in the range of 50 to 100 bar, particularly preferably of over 100 bar.

10. Thermalization plate (30) according to one of the preceding claims, characterized in that the thermalization plate (30) has a positional tolerance of the plate edges of less than 1 mm, preferably less than 0.7 mm, particularly preferably less than 0.4 mm.

11. Thermalization plate (30) according to one of the preceding claims, characterized in that the thermalization plate (30) has a cavity depression of less than 1.5 mm, preferably less than 1 mm, particularly preferably less than 0.7 mm.

12. Thermalization plate (30) according to one of the preceding claims, characterized in that the thickness of the thermalization plate is less than 8 mm, preferably less than 6 mm and especially preferably smaller than 4 mm.

13. Thermalization plate (30) according to one of the preceding claims, characterized in that the cavities of the thermalization plate have a height greater than 1 mm, preferably greater than 3 mm and particularly preferably greater than 5 mm.

14. Plant (1 ,101 ) for semiconductor technology with a thermalizing plate (30) according to one of the preceding claims.

15. System (1 ,101 ) according to claim 14, characterized in that the system is designed as a projection exposure system (1 ,101 ), wafer inspection system or mask inspection system.

16. Method for producing a thermalization sheet (30) for a semiconductor technology system (1, 101), with at least two interconnected thermalization sheet elements (40, 41, 50, 51, 52), wherein at least one thermalization sheet element (40, 41) is produced by an additive manufacturing process, comprising the following process steps: - Production of at least one thermalization sheet element (40,41) using an additive manufacturing process - Joining of the thermalization sheet elements (40,41 ,50,51 ,52) by laser welding, friction stir welding or arc welding.

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