Optical component for a lithography apparatus

Abstract

An optical component (100, 200) for a lithography apparatus (1), comprising an optical element (102, 202), which is produced from a first material (G102) and comprises an optically effective surface (106, 206); and a carrying element (104, 204), which is produced from a second material (G104) and carries the optical element (102, 202), wherein the second material (G104) is different from the first material (G102) and a ratio of the densities of the first and second materials (G102, G104) deviates from 1 by less than 20%, preferably by less than 10%, and even more preferably by less than 5%; wherein the optical element (102, 202) and the carrying element (104, 204) each have a principal extension plane (H102, H202, H104, H204), in which they have a maximum extent, wherein the maximum extent (D102, A202) of the optical element (102, 202) is less than 90%, preferably less than 80%, and even more preferably less than 75%, of the maximum extent (A104, D204) of the carrying element (104, 204).

Description

[0001]OPTICAL COMPONENT FOR A LITHOGRAPHY SYSTEM The present invention relates to an optical component, a use of an optical component, a projection lens, a lithography system, and several methods for producing such an optical component. The content of the priority application DE 102022204268.9 is incorporated by reference in its entirety. Microlithography is used to produce microstructured components, such as integrated circuits. The microlithography process is carried out using a lithography system that has an illumination system and a projection system.The image of a mask (reticle) illuminated by the illumination system is projected by the projection system onto a substrate coated with a light-sensitive layer (photoresist) and arranged in the image plane of the projection system, for example, a silicon wafer, in order to transfer the mask structure onto the light-sensitive coating of the substrate. Driven by the pursuit of ever smaller structures in the manufacture of integrated circuits, EUV lithography systems are currently being developed that use light with a wavelength in the range of 0.1 nm to 30 nm, particularly 13.5 nm. Since most materials absorb light at this wavelength, such EUV lithography systems must use reflective optics, i.e., mirrors, instead of the previously used refractive optics, i.e., lenses.In addition to eliminating the need for refractive media, the move to the EUV range also means a transition to mirror systems that operate either at near-normal incidence or with grazing incidence. At normal incidence, approximately one-third of the incident light is absorbed by each mirror (depending on the specific angle of incidence spectrum); at grazing incidence, typical absorption values ​​are a quarter or a fifth. In refractive media, such as lenses with an anti-reflective coating, the absorbed intensity is in the thousandths range for comparison. This explains the significantly greater temperature changes in EUV optics compared to lens-based systems. The temperature changes are in the range of several Kelvin instead of a few tenths of a Kelvin, as with lens systems.Because temperature gradients translate into surface defects due to the thermal expansion coefficient, they lead to significant optical aberrations, especially in mirrors, which degrade the image relative to the useful wavelength. Accordingly, EUV mirrors are preferably made of materials with particularly low thermal expansion coefficients, such as Zerodur® or ULE® ("Ultralow Expansion" material). These materials counteract components with positive and negative thermal expansion coefficients. The result is an effectively linear relationship between thermal expansion and temperature, with exactly one temperature value at which thermal expansion disappears, namely the so-called zero-crossing temperature. Such materials are particularly complex to manufacture and therefore expensive. Accordingly, the optics made from them are equally cost-intensive.In fact, these costs are one of the major obstacles to increasing the numerical aperture, which requires the use of larger mirrors, i.e. those with a larger diameter. The high material costs are also particularly limiting because, as the mirror diameter increases, its thickness must also be increased in order to limit dynamically generated deformations. Against this background, one object of the present invention is to provide an improved optical component for a lithography system. Accordingly, an optical component for a lithography system is proposed. This comprises an optical element which is made from a first material and has an optically effective surface. Furthermore, the optical component comprises a support element which is made from a second material and supports the optical element. The second material is different from the first material.The ratio of the densities of the first and second materials deviates from 1 by less than 20%, preferably by less than 10%, and even more preferably by less than 5%. The optical element and the support element each have a main extension plane into which they have a maximum extension. The maximum extension of the optical element is less than 90%, preferably less than 80%, and even more preferably less than 75% of the maximum extension of the support element. The present invention is based on the finding that the support element functionally fulfills different tasks than the optical element and can therefore be manufactured from a different, in particular cost-effective material. Nevertheless, the support element or its second material should be as similar as possible to the first material (albeit more cost-effective). Accordingly, a mechanical and / or thermal behavior of the support element can be approximated to that of the optical element.This minimizes negative mechanical interaction between the optical element and the support element. Because the optical element has a smaller maximum extension than the support element (in each case with respect to its main extension plane), it is ensured that the support element can support the optical element over a large area. The main extension plane of the optical element and the main extension plane of the support element are preferably arranged parallel to one another or are at an angle of less than 10 degrees, preferably less than 5 degrees, and even more preferably less than 3 degrees. The "optically effective surface" in this case refers to the surface of the optical element that interacts with the useful light (working light), in particular for the imaging process. The optical component is designed particularly for use in the lithography field.There, it can be used, for example, for lithography systems (DUV and EUV), measuring instruments, or manufacturing devices. According to one embodiment, the optical element and the support element each have a maximum thickness perpendicular to the main extension plane, wherein the maximum thickness of the optical element is less than 90%, preferably less than 80%, even more preferably less than 75% of the maximum thickness of the support element. This advantageously ensures that the support element can absorb the majority of the deformation forces acting on the optical component—for example, during manipulation during operation of the lithography system.According to a further embodiment, the optical element has a side facing away from the optically active surface, wherein the side has a side surface and the optical element is in contact, preferably over its entire surface, with the support element by at least 50%, preferably at least 75%, even more preferably at least 90% of the side surface. This measure also improves the transfer of force from the support element to the optical element, and vice versa. In principle, point-like contact between the optical element and the support element can suffice. However, full-surface contact between the side surface (for example over at least 90% of it) and the support element is preferred because this makes it easier to avoid point-like deformations. Full-surface contact means that 100% of the side surface is in contact with the support element.This somewhat rules out the presence of cooling channels at the interface between the optical element and the support element. According to a further embodiment, the optical element is received in a recess, in particular in a cup-shaped recess, or in a through-opening in the support element. This measure can also improve a force coupling between the optical element and the support element. According to a further embodiment, a material boundary between the first and second material runs partially or completely in a direction perpendicular to the main extension plane of the optical element. In particular, the optical element can be connected to the support element both at its rear side and at one or more peripheral surfaces running perpendicular thereto (or at another angle deviating from perpendicular). This also improves the force coupling.According to a further embodiment, the optical element and the support element are formed integrally with one another. This means that the optical element and the support element are rigidly connected to one another in six degrees of freedom, i.e., immovably. According to a further embodiment, the optical element and the support element are fastened to one another in a force-fitting, material-fitting, and / or positive-locking manner. "Fatigue-fitting" refers to a frictional connection or a connection using magnetic forces. In a "frictional connection," a normal force acts perpendicularly on the surfaces of the optical element and the support element that provide the frictional connection and are in contact with one another. "Material-fitting" refers to a connection using adhesive forces. This can be achieved with the aid of an adhesion-promoting material, such as an adhesive, or even without one. In the latter case, the optical element and the support element adhere directly to one another.This occurs, for example, by wringing or fusing. A "positive fit" refers to a mutual engagement between the connecting partners. This means that the optical element and the support element engage behind each other at one or more fastening points. For this purpose, an engagement and a receiving means are provided, for example, or an additional connecting means (separate part) can be provided, which connects the optical element and the support element to one another in a positive fit. In this case, the fastening means comprises one of the engagement or receiving means. The optical element and the support element in this case have a corresponding receiving or engagement means. The connecting means then connects the optical element and the support element in a positive fit. A fastening means (separate part) can also be used for a force or material fit (indirect fastening).According to a further embodiment, the optical element and the support element are fused, glued, or snapped together. Such a joining technique is advantageous because it ensures uniform force transmission across the surface. Furthermore, the following methods (also in combination with one another) for joining the optical element and the support element to one another can be considered, whereby these can in particular be material-bonded methods: - Glass frit bonding (soldering with glass solder). This connection is advantageously inorganic and can have a melting temperature of, for example, between 300 and 400°C. - Soldering, in particular using metallic solders. This type of connection is advantageously inorganic. In particular, low-melting solders with a melting temperature of, for example, 60 - 400°C, preferably 60 - 250°C, can be used.A solder with a melting point greater than 200°C is particularly preferred. - Diffusion-driven processes, such as thermo-compression bonding, solid-liquid interdiffusion bonding, and / or eutectic joining. - Welding, in particular: beam-based welding, such as laser welding. The following procedure can be chosen for this: polishing the surfaces of the components to be joined (here: optical element and / or support element), blasting the components together, focusing the laser in the area of ​​the joining surfaces and melting partial areas, thereby joining the components. Friction welding, possibly in conjunction with a metallic coating. Cold welding processes, in particular diffusion-driven joining processes, for example, accelerated by an elevated temperature or an increased joining pressure.In this regard, the following process can be selected: First, the surfaces of the components to be joined (here: optical element and / or support element) are polished, then the components are pressed together. The components then rest until the material exchange in the connecting surfaces leads to the desired strength. - Silicate joining and / or hydroxide-based joining, especially for silicon-containing materials. - Reactive joining. - Anodic bonding. - Surface-activated bonding, especially using a metallic coating.According to a further embodiment, the first and second materials differ in one or more of the following properties: a refractive index homogeneity, a proportion and / or size of inclusions, in particular bubbles, a stress birefringence, an intrinsic polarization birefringence, a transmittance, in particular at the operating wavelength of the optical element, a density and / or a change in density in at least one spatial direction, a hardness or a change in hardness in at least one spatial direction, a roughness, a slumping property, and a resistance to compaction and / or solarization. Advantageously, differences between the first and second materials are permitted with regard to these properties, thereby reducing the manufacturing costs for the second material.In detail, the properties can be defined as follows: The procedure for determining the refractive index homogeneity is as follows: A refractive index distribution is determined over their respective volumes for both the optical element and the support element (which in this case are designed as refractive optics). Subsequently, one or more variables characterizing the variation in the refractive index over the volume are determined. One such variable is, for example, a peak-valley value, an RMS value (“root mean square”) or an expansion coefficient of a fit of one or more curve functions to the measured distribution. The curve functions can in particular be products of Legendre polynomials or Zernike functions. The one or more characterizing variables of the optical element are then compared with those of the support element."Homogeneity" in the present sense exists, for example, when the ratio of the quantities characterizing the variation, or the largest of the respective ratios in the case of several such quantities, is less than 150%. The refractive index, also known as the refractive index, is the ratio of the speed of light in a vacuum, c0, to the propagation speed, c. Mof the light in the respective medium (i.e. the first or second material). The proportion of inclusions in the first or second material can be expressed as a volume percent. The size of the inclusions can be specified as the largest dimension, e.g. largest diameter. For example, the largest bubble in the first material can be compared with the largest bubble in the second material, with a maximum diameter being used in each case. A difference in the volume fraction and / or size of inclusions can, for example, be greater than 5%, greater than 10%, or greater than 20%. Stress birefringence can be determined by detecting a loss of contrast of light passing through the first or second material. The loss of contrast is the result of the change in polarization direction. The loss of contrast can be specified in nanometers per centimeter.For example, a difference in the maximum value of the stress birefringence between the first and second materials can be 0.2 nm / cm, 0.5 nm / cm, or 1.0 nm / cm. For example, the intrinsic polarization birefringence of the first material can correspond to that of a calcium fluoride crystal or lie within a tolerance window corresponding to a predetermined accuracy of the crystal orientation around a predetermined value. The tolerance window can be, for example, -5°, -10°, -20° to 5°, 10°, or 20°. For example, the crystal orientation in the calcium fluoride crystal can be 100, 111, or 110. In contrast, the second material has no intrinsic birefringence. Likewise, both materials may have an intrinsic polarization birefringence, wherein the deviation of this birefringence in the first material is less than 0.1 nm / cm, 0.2 nm / cm or 0.5 nm / cm from a designed value for this intrinsic birefringence.The true crystal orientation deviates by less than 5°, 10°, or 20° from a designed value for the crystal orientation, while the deviation in the second material is correspondingly higher, e.g., by at least 20% or 50%. The cause of this deviation can be a different degree of precision in setting the true crystal orientation angle relative to a predetermined angle in the respective material. The transmittance k is defined here as the ratio of the amount of light I radiating onto the optical element or the support element. ein to the amount of light I leaving the optical element or support element ver defined, where the ratio is given as: , where "L" describes the distance in the first or second material through which the incoming light radiates. The distance is specified in meters, for example. The difference in transmittance between the optical element and the support element is, for example, greater than 5%, greater than 10%, or greater than 20%. The density, expressed as mass per volume, or its change, i.e., the gradient in a spatial direction, of the first material preferably deviates by greater than 5%, greater than 10%, or greater than 20% from the density or change therein of the second material. A "slumping property" is understood here as follows: The optical element, but also the support element (although less preferred) can have a layered structure. During production, a layered blank is placed in or onto a curved mold and heated therein.Accordingly, the layer stack (in a state that is deformable thanks to the high temperature) also takes on the corresponding shape uniformly, with the layer sequence along the surface normal being largely retained. This process can be used to create a high-quality component. In particular, the optical component can be produced with the desired curvature on its optically effective surface. A difference between the first and second materials with regard to their slumping properties can either consist in the fact that the first material or the optical element was produced using a slumping process, as described above, and the second material or the support element was not produced using such a process. If both the first and second material (orIf the first material (optical element and support element) has been manufactured using a slumping process, the thicknesses of the layer sequence along the surface normal can differ to varying degrees from a desired target state. In particular, the layer thickness accuracies of the first material or the optical element can be closer than 10%, closer than 25%, or closer than 50% to a specified value on average or at maximum compared to the layer thickness accuracies of the second material or the support element to this specified value, likewise on average or at maximum. To harden quartz glass or other materials against compaction and solarization due to the breaking of bonds by the high-energy useful radiation (working light), loading with hydrogen or similar pretreatment can be carried out, which is often time-consuming.Accordingly, irradiation of the (suitably selected and / or treated) first material with a predetermined number of laser pulses can result in a 50%, preferably 80%, more preferably 90% lower change in refractive index or transmission compared to the second material, with the same test specimen and irradiation geometry. In particular, the loading time of the first material with hydrogen can be at least 50%, 100%, or 200% longer than that of the second material. The roughness of the surface of the optical element in a spatial frequency range of 10 nm - 1 mm can be characterized by an RMS value that is a factor of 5, 10, or 20 or more lower than that of the support element and can in particular be less than 0.5 nm, 0.3 nm, or 0.1 nm. Corresponding ratios of the RMS values ​​can also be present in individual bands for spatial frequencies, for example in the band 100 µm – 1 mm, 10 µm – 100 µm, 1 µm – 10 µm or 100 nm – 1 µm.According to a further embodiment, at an expected average operating temperature, the thermal expansion coefficient of the first material is at least ten times lower than the thermal expansion coefficient of the second material. This also ensures that the first material is of higher quality than the second material. The expected average operating temperature depends on the intended use of the optical component. According to a further embodiment, the support element has one or more of the following components: a mechanical interface for attaching it to a support frame of a lithography system and / or for attaching an actuator, and / or a measurement object for measuring the position of the support element with the aid of a measuring device.This requires the support element to perform specific functions that differ from those of the optical element, which itself has the optically effective surface (function of the optical element). According to a further embodiment, the optical element is a mirror, a lens, a polarization-optical element, in particular a retarder plate, a polarization filter or a rotation element designed to rotate a direction of polarization, a color filter and / or an optical grating. According to a further embodiment, the first material is ultralow expansion material (ULE®), Zerodur®, calcium fluoride and / or quartz glass and / or the second material is quartz glass, optical glass, glass ceramic, silicon, SiSiC or steel, in particular Invar®. Accordingly, the first material is of higher optical quality than the second material, while the second material is more cost-effective. ULE is titanium-doped quartz glass. Zerodur is a glass ceramic.Invar is an iron-nickel alloy with 64% iron and 36% nickel. SiSiC is a silicon carbide. According to a second aspect, a use of the optical component as described above is provided. The optical component is used in an imaging process, wherein a working light used has a wavelength of less than 120 nm, preferably 30 nm. The working light interacts with the optically effective surface of the optical element. According to a third aspect, a projection lens, in particular a catadioptric projection lens or with a pure mirror system, is provided. The projection lens has an optical component as described above. In particular, the optical element of the component can be a lens that is arranged close to the field or intermediately in the beam path. Alternatively, the component is a mirror or another optical element.According to a fourth aspect, a lithography system, in particular an EUV or DUV lithography system, is provided. This comprises the optical component as described above or a projection lens as described above. EUV stands for "Extreme Ultraviolet" and denotes a wavelength of the working light between 0.1 nm and 30 nm. DUV stands for "Deep Ultraviolet" and denotes a wavelength of the working light between 30 nm and 250 nm. According to a fifth aspect, a method for producing an optical component as described above is provided. The method comprises the steps: a) simulating properties of the optical component during operation; b) adapting at least one of these properties depending on the simulation; and c) producing the optical component with the adapted property.This method is based on the consideration that the use of the first (expensive) material and the second (less expensive) material is adapted to the relevant usage scenarios. According to a further embodiment, the properties of the optical component during operation are simulated in a first simulation according to step a). In a further step, a manufacturing effort for manufacturing the optical component is simulated in a second simulation. The at least one property is then adapted according to step b) depending on the first and second simulation. The manufacturing effort can be expressed, for example, in machine hours, material costs, etc. This makes it easy to determine a solution that is suitable both in terms of optics and in terms of manufacturing costs. According to a further embodiment, the properties simulated according to step a) comprise an optical property of the optically effective surface.The optical property is, for example, thermal expansion, a refractive index, a surface deformation, or an aberration, even across the projection lens or the lithography system. This particularly refers to an aberration on a wafer to be exposed. According to a further embodiment, adapting the at least one property according to step b) comprises adapting a dimension of the optical element and / or the support element and / or adapting the first or second material. Thus, if it is determined that, for example, the optical property does not yet meet the requirements, the optical element can be made larger (in particular with a larger volume). Additionally or alternatively, an optically better first material can be used.According to a further embodiment, a correction means for adapting the at least one property of the optical element is determined, wherein the correction means is provided outside the optical component. Advantageously, the desired optical property can be achieved not only by adapting the optical element or the support element. Rather, known correction means—in particular from the prior art—can be used in order to (nevertheless) be able to use a smaller optical element or an optical element made of a lower-quality first material. According to a sixth aspect, a method for producing an optical component for a lithography system is provided.This comprises the steps: a) manufacturing an optical element from a first material having an optically effective surface; and b) manufacturing a support element from a second material, wherein the second material is different from the first material and a ratio of the densities of the first and second materials deviates from 1 by less than 20%, preferably by less than 10%, and even more preferably by less than 5%; c) connecting the optical element to the support element such that the support element supports the optical element, wherein the optical element and the support element each have a main extension plane in which they have a maximum extension, wherein the maximum extension of the optical element is less than 90%, preferably less than 80%, and even more preferably less than 75% of the maximum extension of the support element. Steps a) to c) can in principle be carried out in any order.For example, the support element can be manufactured first and the optical element produced immediately afterwards, i.e. steps a) and c) take place simultaneously and after step b). According to one embodiment, in step a) a variation in a removal rate at which the first material is removed is greater than 20%. Alternatively or additionally, in step b) a variation in a removal rate at which the second material is removed is less than or equal to 20%. The greater the variation in the removal rate, the more complex the processing. For example, the removal rate varies when different crystal structures or planes each have to be removed with high quality - for example, in the case of machining a curved shape from calcium fluoride. If, for example, a suitable refractive index is to be achieved in lenses, a correspondingly large variation in the removal rate (for example greater than 20%) may be necessary.On the other hand, a load-bearing element can be manufactured cost-effectively with only a small variation in the removal rate (approximately less than 20%). The removal rate is expressed, for example, as mm. 3 / h (i.e., material volume removed per unit of time). The variation refers, for example, to the entire manufacturing process from the material blank to the (finished) optical element or support element. The removal rate can refer to removal by means of, for example, milling or polishing. According to a further embodiment, the manufacturing in step a) and / or step b) comprises the use of a slumping process, wherein a maximum or average deviation of an actual layer thickness from a target layer thickness is preferably smaller for the first material than for the second material. Accordingly, the first material is of higher quality than the second material, and the latter is more cost-effective to manufacture. "One" is not necessarily to be understood as being limited to exactly one element. Rather, multiple elements, such as two, three, or more, can also be provided.Any other counting term used here should not be understood as implying a limitation to the exact number of elements stated. Rather, numerical deviations upwards and downwards are possible unless stated otherwise. The embodiments and features described for the first aspect apply accordingly to the other aspects, and vice versa. Further possible implementations of the invention also include combinations not explicitly mentioned of features or embodiments described previously or below with regard to the exemplary embodiments. In this case, the person skilled in the art will also add individual aspects as improvements or additions to the respective basic form of the invention. Further advantageous embodiments and aspects of the invention are the subject matter of the dependent claims and the exemplary embodiments of the invention described below.The invention is explained in more detail below using preferred embodiments with reference to the attached figures. The embodiments and features described for the first aspect apply accordingly to the other aspects described here and vice versa. Fig. 1 shows a schematic meridional section of a projection exposure system for EUV projection lithography; Fig. 2 shows a perspective view of a section from a lithography system according to one embodiment; Fig. 3 shows a partial section III from Fig. 2; Fig. 4 shows a section of a top view IV from Fig. 2; Fig. 5 shows a view V from Fig. 4; Fig. 6 shows a section through an optical component according to a further embodiment; Fig. 7 shows a section through an optical component according to a still further embodiment; Fig. 8 shows a section through an optical component according to a still further embodiment;9 shows a section through an optical component according to yet another embodiment; FIG. 10 shows a side view of an optical component with a lens according to an embodiment; FIG. 11 shows a view XI from FIG. 10; FIG. 12 shows a flow chart of a method according to an embodiment; FIG. 13 shows a method step in a slumping method; FIG. 14 shows a view XIV from FIG. 13; and FIG. 15 shows a flow chart of a method according to an embodiment. In the figures, identical or functionally equivalent elements have been provided with the same reference numerals unless stated otherwise. Furthermore, it should be noted that the representations in the figures are not necessarily to scale. FIG. 1 shows an embodiment of a projection exposure system 1 (lithography system), in particular an EUV lithography system.One embodiment of an illumination system 2 of the projection exposure system 1 has, in addition to a light or radiation source 3, illumination optics 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 illumination system 2. In this case, the illumination system 2 does not include the light source 3. A reticle 7 arranged in the object field 5 is exposed. The reticle 7 is held by a reticle holder 8. The reticle holder 8 can be displaced, in particular in a scanning direction, via a reticle displacement drive 9. For the purpose of explanation, Fig. 1 shows a Cartesian coordinate system with an x-direction x, a y-direction y, and a z-direction z. The x-direction x runs perpendicular into the drawing plane. The y-direction y runs horizontally and the z-direction z runs vertically.The scanning direction in Fig. 1 runs along the y-direction y. The z-direction z runs perpendicular to the object plane 6. The projection exposure system 1 comprises projection optics 10. The projection optics 10 serve to image the object field 5 into an image field 11 in an image plane 12. The image plane 12 runs 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. A structure on the reticle 7 is imaged onto a light-sensitive layer of a wafer 13 arranged in the region of the image field 11 in the image plane 12. The wafer 13 is held by a wafer holder 14. The wafer holder 14 can be displaced, in particular along the y-direction y, via a wafer displacement drive 15. The displacement of the reticle 7 on the one hand via the reticle displacement drive 9 and the wafer 13 on the other hand via the wafer displacement drive 15 can be synchronized with each other.The light source 3 is an EUV radiation source. The light 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 16 has, in particular, a wavelength in the range between 5 nm and 30 nm. The light 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. The light source 3 can be a free-electron laser (FEL). The illumination radiation 16 emanating from the light source 3 is bundled by a collector 17.The collector 17 can be a collector with one or more ellipsoidal and / or hyperboloidal reflection surfaces. The at least one reflection surface of the collector 17 can be exposed to the illumination radiation 16 at grazing incidence (GI), i.e., at angles of incidence greater than 45°, or at normal incidence (NI), i.e., at angles of incidence less than 45°. The collector 17 can be structured and / or coated, on the one hand, to optimize its reflectivity for the useful radiation and, on the other hand, to suppress stray light. 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 light source 3 and the collector 17, and the illumination optics 4.The illumination optics 4 comprises a deflecting mirror 19 and, downstream of this in the beam path, a first facet mirror 20. The deflecting mirror 19 can be a flat deflecting mirror or, alternatively, a mirror with a beam-influencing effect beyond the pure deflection effect. Alternatively or additionally, the deflecting mirror 19 can be designed as a spectral filter that separates a useful light wavelength of the illumination radiation 16 from stray light of a different wavelength. If the first facet 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 facet mirror. The first facet mirror 20 comprises a plurality of individual first facets 21, which can also be referred to as field facets. Only a few of these first 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 partially circular edge contour. The first facets 21 can be designed as flat facets or alternatively as convexly or concavely curved facets. As is known, for example, from DE 102008009600 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 designed as a microelectromechanical system (MEMS system). For details, reference is made to DE 102008009600 A1. Between the collector 17 and the deflecting mirror 19, the illumination radiation 16 runs horizontally, i.e. along the y-direction y. In the beam path of the illumination optics 4, a second facet mirror 22 is arranged downstream of the first facet mirror 20.If the second facet mirror 22 is arranged in a pupil plane of the illumination optics 4, it is also referred to as a pupil facet mirror. The second facet 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 facet mirror 20 and the second facet mirror 22 is also referred to as a specular reflector. Specular reflectors are known from US 2006 / 0132747 A1, EP 1614 008 B1, and US Pat. No. 6,573,978. 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. The second facets 23 may also be macroscopic facets, which may, for example, be round, rectangular or hexagonal in shape, or alternatively facets composed of micromirrors.In this regard, reference is also made to DE 102008009600 A1. The second facets 23 can have flat or, alternatively, convex or concave curved reflection surfaces. The illumination optics 4 thus forms a double-faceted system. This basic principle is also referred to as a fly's eye integrator. It may be advantageous not to arrange the second facet mirror 22 exactly in a plane that is optically conjugate to a pupil plane of the projection optics 10. In particular, the second facet mirror 22 can be tilted relative to a pupil plane of the projection optics 10, as described, for example, in DE 102017220586 A1. With the aid of the second facet mirror 22, the individual first facets 21 are imaged into the object field 5.The second facet mirror 22 is the last bundle-forming or actually the last mirror for the illumination radiation 16 in the beam path in front of the object field 5. In a further embodiment of the illumination optics 4 (not shown), a transmission optics can be arranged in the beam path between the second facet mirror 22 and the object field 5, which transmission optics contributes in particular to the imaging of the first facets 21 in the object field 5. The transmission optics can have exactly one mirror, but alternatively also two or more mirrors, which are arranged one behind the other in the beam path of the illumination optics 4. The transmission optics can in particular comprise one or two mirrors for normal incidence (NI mirrors, normal incidence mirrors) and / or one or two mirrors for grazing incidence (GI mirrors, gracing incidence mirrors). The illumination optics 4 has, in the embodiment shown in Fig.1, after the collector 17 there are exactly three mirrors, namely the deflecting mirror 19, the first facet mirror 20 and the second facet mirror 22. In a further embodiment of the illumination optics 4, the deflecting mirror 19 can also be omitted, so that the illumination optics 4 can then have exactly two mirrors after the collector 17, namely the first facet mirror 20 and the second facet 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 optics into the object plane 6 is generally only an approximate imaging. The projection optics 10 comprises a plurality of mirrors Mi, which are numbered according to their arrangement in the beam path of the projection exposure system 1. In the example shown in Fig. 1, the projection optics 10 comprises six mirrors M1 to M6.Alternatives with four, eight, ten, twelve or a different number of mirrors Mi are also possible. The projection optics 10 are doubly obscured optics. The penultimate mirror M5 and the last mirror M6 each have a passage opening for the illumination radiation 16. The projection optics 10 has an image-side numerical aperture that is greater than 0.5 and can also be greater than 0.6 and can be, for example, 0.7 or 0.75. Reflection surfaces of the mirrors Mi can be designed as freeform surfaces without a rotational symmetry axis. Alternatively, the reflection surfaces of the mirrors Mi can be designed as aspherical surfaces with exactly one rotational symmetry axis of the reflection surface shape. The mirrors Mi, just 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. The projection optics 10 have a large object-image offset in the y-direction y 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 y can be approximately as large as a z-distance between the object plane 6 and the image plane 12. The projection optics 10 can, in particular, be anamorphic. In particular, it has different image scales βx, βy in the x- and y-directions x, y. The two magnifications βx, βy of the projection optics 10 are preferably (βx, βy) = (+ / - 0.25, / +- 0.125). A positive magnification β means an image without image inversion. A negative sign for the magnification β means an image with image inversion.The projection optics 10 thus results in a reduction in the ratio 4:1 in the x-direction x, i.e., in the direction perpendicular to the scanning direction. The projection optics 10 results in a reduction in the y-direction y, i.e., in the scanning direction. Other image scales are also possible. Image scales with the same sign and absolutely identical in the x- and y-directions x, y, for example, with absolute values ​​of 0.125 or 0.25, are also possible. The number of intermediate image planes in the x- and y-directions x, y 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, can be different. Examples of projection optics with different numbers of such intermediate images in the x and y directions x, y are known from US 2018 / 0074303 A1.Each of the second facets 23 is assigned to exactly one of the first facets 21 to form a respective illumination channel for illuminating the object field 5. This can result in particular in illumination according to the Köhler principle. The far field is broken down into a plurality of object fields 5 with the aid of the first facets 21. The first facets 21 generate a plurality of images of the intermediate focus on the second facets 23 respectively assigned to them. The first facets 21 are each imaged onto the reticle 7 by an assigned second facet 23, superimposed on one another, to illuminate the object field 5. The illumination of the object field 5 is in particular as homogeneous as possible. It preferably has a uniformity error of less than 2%. Field uniformity can be achieved by superimposing different illumination channels.By arranging the second facets 23, the illumination of the entrance pupil of the projection optics 10 can be geometrically defined. By selecting the illumination channels, in particular the subset of the second facets 23 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 illumination setting or illumination pupil filling. A likewise preferred pupil uniformity in the area of ​​defined illuminated sections of an illumination pupil of the illumination optics 4 can be achieved by redistributing the illumination channels. 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 can, in particular, have a homocentric entrance pupil. This can be accessible. It can also be inaccessible.The entrance pupil of the projection optics 10 cannot usually be precisely illuminated with the second facet mirror 22. When the projection optics 10 images the center of the second 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 in which the pairwise determined distance of the aperture rays is minimized. This surface represents the entrance pupil or a surface conjugated to it in spatial space. In particular, this surface exhibits a finite curvature. The projection optics 10 may have different positions of the entrance pupil for the tangential and for the sagittal beam path. In this case, an imaging element, in particular an optical component of the transmission optics, should be provided between the second facet mirror 22 and the reticle 7.With the help of this optical element, the different positions of the tangential entrance pupil and the sagittal entrance pupil can be taken into account. In the arrangement of the components of the illumination optics 4 shown in Fig. 1, the second facet mirror 22 is arranged in a surface conjugated to the entrance pupil of the projection optics 10. The first facet mirror 20 is arranged tilted to the object plane 6. The first facet mirror 20 is arranged tilted to an arrangement plane defined by the deflection mirror 19. The first facet mirror 20 is arranged tilted to an arrangement plane defined by the second facet mirror 22. Fig. 2 shows a section of the lithography system 1 from Fig. 1. An optical component 100 can be seen, which comprises an optical element 102 and a support element 104. The optical element 102 can in particular be one of the mirrors M1 to M6 from Fig.1, or an optical element from any other optical system (e.g. a measuring system for use in lithography). In particular, it could be one of the mirrors from the illumination system 2 in Fig. 1. In principle, the optical element 102 can be a mirror, a lens, a polarization-optical element, in particular a retarder plate, a polarization filter or a rotation element which is designed to rotate a direction of polarization, a color filter or an optical grating. In the exemplary embodiment according to Fig. 2, the optical element 102 is a mirror. The optical element 102 has an optically effective surface 106. The illumination radiation 16 (see also Fig. 1) or the working light is reflected at this surface. The illumination radiation is preferably EUV radiation, i.e. light with a wavelength between 0.1 and 30 nm.The optical element 102 is made of a first material. This can be, for example, ULE, Zerodur, calcium fluoride, or quartz glass. This makes the manufacture of the optical element 102 comparatively expensive. The support element 104 supports the optical element 102. This means, in particular, that the forces resulting from the force of gravity acting on the optical element 102 are partially or entirely introduced into the support element 104 from the optical element 102. In addition to the force of gravity, dynamic loads, such as those resulting from vibrations or other accelerations, can be added. The support element 104 is made of a second material. The second material can be made, for example, from quartz glass, optical glass, glass ceramic, silicon, SiSiC (silicon carbide), or steel, in particular Invar.Accordingly, the second material is a comparatively inexpensive material, so that the manufacturing costs for the optical component 100 are reduced overall. Fig.3 shows a section III from Fig.2. There it can be seen that the first material G. 102 from the second material G 104 In particular, the ratio of the densities ρ G102 , ρ G104 of the first and second material G 102 , G 104 (first material G 102 with the first density ρ G102 , second material G 104 with the second density ρ G104 ): where x is: 20%, preferably 10%, and even further 5%. The above formulas (1) to (4) apply cumulatively. In other words, the first and second materials are comparable in terms of their density, so that acceptable differences exist between them in mechanical and / or thermal terms. Preferably, the ratio of the densities ρG102 , ρ G104 of the first and second material G 102 , G 104 within the above limits of 1, 1.0, 1.00, 1.000 or 1.0000. For example, the first material G 102 ULE with a density of 2.21 g / cm 3 (at 25 °C), as second material G 104 a quartz glass with a density of 2.20 g / cm 3 (at 25 °C). Accordingly, the ratio ρ G102 to ρ G104 1.005 and is therefore within the limits defined above. The first and second materials may differ, for example, in the proportion and size of inclusions, particularly bubbles 108, 110. As can be seen in Fig. 3, the diameter D 110 the bubbles 110 in the material G 104 larger than the diameter D 108 of the bubbles 108 in the material G 102 . In addition, the material G 102 and G 104with regard to the proportion, expressed in volume percent, of the bubbles 108, 110. In addition or alternatively, the first and second material G 102 , G 104 in a number of further properties: Examples include a refractive index homogeneity, a stress birefringence, an intrinsic polarization birefringence, a transmittance, in particular at the operating wavelength of the optical component 100, a density or a density change in at least one spatial direction, a hardness or a change in hardness in at least one spatial direction, a slumping property, a roughness, and a resistance to compaction and / or solarization, in particular by the useful radiation. The thermal expansion coefficient of the first material G 102 is preferably at least ten times lower than a thermal expansion coefficient of the material G 104, namely at a temperature of the first and second material G 102 , G 104at an average expected operating temperature, which can be in a range between 22°C and 32°C, for example. Returning now to Fig. 2, it can be seen that the optical component 100 is supported on a support frame 114 of the lithography system 1 by means of an actuator 112 in a way that can be manipulated in space. For this purpose, the support element 104 has a mechanical interface 116 (e.g. a pin). A flexure joint 118 is attached to the interface 116. The flexure joint 118 connects a pin 120 to the interface 116 so that it can be pivoted through two degrees of freedom. The pin 120 is moved along its longitudinal axis 122 with the aid of the actuator 112 in order to change the position of the optical component 100 or the optically effective surface 106 in space. The interface 116 could be any other mechanical interface. Additionally or alternatively, the support element 104 may have a measurement object 124.According to the exemplary embodiment, the measurement object 124 is a reflector. This reflects a measurement beam 126. The measurement beam 126 is emitted, for example, by an interferometer 128, which in turn is attached to a sensor frame 130. With the aid of the measuring arrangement 132, comprising the interferometer 128 and the measurement object 124, the actual position (position and orientation) of the optically effective surface 106 can be determined. Fig. 4 shows a plan view IV from Fig. 2, specifically viewed opposite the z-direction (vertical direction) in Fig. 2. The vectors x, y describe a horizontal plane perpendicular to the vector z. Fig. 5 shows a view V from Fig. 4. The optical element 102 has a main extension plane H. 102 (see Fig.5), the support element 104 has a main extension plane H 104(see also Fig. 5). The main extension plane is the plane in which the respective component 102, 104 essentially extends. The respective extension in the main extension plane is greater than in any other plane. The main extension plane H 102 , H 104 According to the exemplary embodiment, the planes lie in the xy-plane. In Fig.4, the main planes of extension H 102 , H 104 (not shown) one above the other and parallel to the plane of the paper. In their respective main extension plane H 102 , H 104 The optical element 102 and the support element 104 each have a maximum dimension. This is the diameter D102 of the optical element 102 and the diagonal A of the support element 104. 104 . The diameter D102 is less than 90%, preferably less than 80% and more preferably less than 75% of the diagonal A 104 . Perpendicular to the main extension planes H 102 , H104 The optical element 102 and the support element 104 each have a maximum thickness. According to the exemplary embodiment, the thickness indicates the maximum extension in the z-direction. The thickness T shown in Fig. 5 102 (maximum thickness) of the optical element 102 is preferably less than 90%, preferably less than 80%, even more preferably less than 75% of the maximum thickness T 104of the support element 104. As can also be seen in Fig. 5, the rear side 134 of the optical element 102, i.e. the side facing away from the optically effective surface 106, is in full-surface contact with the surface 136 of the support element 4. The surface 136 (see also Fig. 2) of the support element 102 is the surface of the support element 104 facing the optical element 102. Instead of the full-surface contact over 100% of the rear side 134 shown, it could also be provided that the rear side 134 of the optical element 102 is in contact with the support element 104 (only) to at least 50%, preferably at least 75%, and even more preferably at least 90%. For example, ribs could be formed on the surface 136, which correspondingly reduce the contact of the back side 134 with the surface 136.According to the exemplary embodiment, the optical element 102 and the support element 104 are formed as a single piece, wherein according to the exemplary embodiment shown in Figures 2 to 5, they are formed integrally with one another. The integral bond is created by the optical element 102 and the support element 104 preferably being fused, glued, or snapped together. A thermal connection is preferred in which high temperatures above the glass transition temperature are set in the vicinity of the separating surface (rear side 134, surface 136) so that the optical element 102 and the support element 104 are bonded to one another there. During the cooling process, frozen-in thermal stresses are preferably largely avoided, which is achieved, for example, by adhering to a predetermined cooling curve in which a maximum value for the temporal temperature gradient is not exceeded, particularly at high temperatures.Subsequent tempering steps can alternatively relieve such stresses. In particular, it can also be provided that welding is carried out at the interface. For example, a laser beam 138 from a laser source 140 can be used at the interface to fuse the surfaces 134, 136 together. Fig. 15 illustrates, in a flowchart, an embodiment of a method for producing the component 100, for example as described in Figs. 2 to 5. In a step K1, the optical element 102 is coated with the material G. 102 In a step K2, the support element 104 is made of material G 104manufactured. For example, step K2 can take place before, after, or simultaneously with step K1. In a step K3, the optical element 102 and the support element 104 are connected to one another (for example, glued, exploded, lasered, or fused in some other way) such that the support element 104 supports the optical element 102. This includes the possibility of the optical element 102 and the support element 104 being integrally formed (for example, by casting or in a slumping process, see also the following explanations with reference to Figs. 13 and 14) and thus being connected to one another in a common manufacturing process. Furthermore, the support element 104 can be manufactured first, and then the optical element 102 can be initial formed and thereby simultaneously connected to the support element 104.Furthermore, it is possible for the support element 104 to be produced on the optical element 102 by primary forming and thereby connected to it. In particular, the optical element 102 and / or support element 104 are machined to remove material in order to produce the optical component 100 suitable for its intended use, in particular in a projection exposure system 1. A removal process can in particular comprise milling or polishing. Depending on the processing quality to be achieved, the removal rate, ie, the volume of material removed per unit time, for example in mm. 3 / h, more or less. For the high-quality optical element 102, the removal rate at which the first material G 102is removed, over the entire material-removing machining process, preferably by more than 20%, more preferably by more than 30%, even more preferably by more than 50%. This allows the machining process to be adapted with high precision to the respective, in particular crystalline, structure of the first material G 102 In contrast, the removal rate varies with respect to the second material G 104 (again over the entire material-removing machining process) by less than 50%, preferably by less than 30%, and even more preferably by less than 20%. High-precision machining of the second material G 104is preferably not provided in order to reduce the effort. Fig. 6 shows a sectional view of an optical component 100 according to a further embodiment. In this embodiment, the optical element 102 is embedded in the support element 104 such that both its rear side 134 and a peripheral surface 142 rest against a corresponding surface 136 or corresponding side surfaces 144 of the support element 104 and / or is fastened there. In particular, the surface 136 and the side surfaces 144 can define a pot-shaped depression 145 into which the optical element 102 is fitted. The peripheral surface 142 can be at an angle α of 90° to the rear side 134. However, other angles deviating from 90° are also conceivable. For example, the angle α can be between 90° and 110°.This can facilitate fitting the optical element 102 into the support element 104 or into the corresponding cup-shaped opening. Fig. 7 shows a further example of an optical element 100. In this embodiment shown in section, the angle α spanned between the rear side 134 and the peripheral surface 142 is less than 90°, for example between 70° and 90°, in particular between 70° and 85°. In this embodiment, the optical element 102 is cast into the support element 106 or into the cup-shaped opening formed thereby. In the sectional view of an optical element 100 according to a further embodiment shown in Fig. 8, the optical element 102 is adhesively bonded to the support element 104 with the aid of an adhesive 146. In particular, the rear side 134 of the optical element 102 is adhesively bonded to the surface 136 of the support element 104. Accordingly, Fig.8 shows an example of an indirect fastening of the optical element 102 to the support element 104. This differs from the exemplary embodiments according to FIGS. 2 to 7, in which the optical element 102 is preferably fastened directly to the support element 104, in particular by a material bond. FIG. 9 also shows an embodiment of an indirect fastening. In this case, the optical element 102 is fastened to the support element 104 with the aid of an intermediate frame 148. The intermediate frame 148 can be made of metal, for example Invar. The intermediate frame 148 holds the optical element 102 at a distance from the support element 104. The intermediate frame 148 can be fastened to the support element 104, for example, with the aid of screws 150 or other fastening means. The optical element 102 can, for example, be glued to holding elements, in particular feet 152, of the intermediate frame 148, although other fastening options are also conceivable. Fig.10 shows an embodiment of an optical component 200 in which a lens is provided as the optical element 202. FIG. 10 shows the optical component 200 in a side view. The optical element 202 is integrated into a support element 204. The support element 204 is fastened to a support frame 214 of a DUV lithography system (not shown in detail). For this purpose, for example, a mount 260 can be provided which connects the support element 204 to the support frame 214. Working or useful light 262 falls on an optically effective surface 206 of the optical element 202 and penetrates it on its way, for example, to a wafer (not shown). The optical element 202 is formed integrally with the support element 204 on its peripheral surface 242. The peripheral surface 242 describes, for example, as can be seen in FIG. 11, a closed, annular contour.The contour can be, for example, circular, oval, rectangular with rounded corners, trapezoidal, or otherwise suitably formed. The decisive factor for the geometry of the peripheral surface 242 is merely that imaging with the aid of the optical element 202 can be achieved with sufficient quality. At its peripheral surface 242, the optical element 202 is connected to the support element 204, in particular by a material fit. This can be achieved in particular by fusing the optical element 202 to the support element 204. The optical component 200 or the optical element 202 and the support element 204 can together define a disk-shaped geometry. According to the exemplary embodiment, this is curved on at least one side, in the exemplary embodiment, the side 264, which also contains the optically active surface 206. The opposite side 266 can be straight.In principle, the optical component 200 or its side surfaces 264, 266 can define a biconvex, plano-convex, concave-convex, convex-concave, plano-concave, or biconcave shape. Preferably, the side 264 or the corresponding surface is formed continuously, i.e., in particular, without a step, with the region of the optically effective surface 206. The light exit side 268 of the optical element 202 is also preferably formed continuously, i.e., in particular, without a step, with the surrounding region of the side 266. In Fig. 10, the main extension planes H are shown. 202 , H 204 of the optical element 202 or the support element 204 (see Fig. 10). A diagonal A 202 in Fig.11 corresponds to the maximum extension of the optical element 202 in its main extension plane H 202 . The maximum extension of the supporting element 204 in its main extension plane H 204corresponds to its diameter D 204 (see Fig.11). The maximum extension A 202 is less than 90% of the maximum extension D 204, preferably less than 80% and even more preferably less than 75%. In the embodiment according to Figures 10 and 11, this value is 85%. In particular, lens systems can also be produced in this way which have regions (lens 202) with a high refractive index homogeneity requirement, with low stress birefringence, with a transmittance above a predetermined limit for the operating wavelength and / or with a high robustness against irradiation at the operating wavelength (for example with regard to compaction or solarization) and / or are characterized by a special, for example low or predetermined oriented intrinsic birefringence in the optically penetrated volume and relaxed requirements outside (in the region of the support element 204) thereof.Catadioptric designs with geometric beam splitting, in particular, utilize near-field lens systems with an off-axis footprint, while a rotationally symmetric lens body (lens 202) is often used for mechatronic compatibility and symmetrical mounting technology. The assembly or insertion (see Figs. 1 to 5, 8, 9, and Figs. 6, 7, 10, and 11) of the optical element 102, 202 with or into the support element 104, 204 can lead to deformation, necessitating subsequent processing steps to adjust the end fit. Alternatively, it is possible to carry out all processing steps, including the coating, before inserting the optical element 102, 202 into the support element 104, 204 or before joining, and to compensate for the deformation resulting from the joining process by subsequent locally variable material compaction by means of electron or ion irradiation in a process such as ICE-T.Such methods are described, for example, in the documents DE 10 2011084 117 A1, DE 102015201141 A1, DE 102012223669 A1, DE 102014 225197 A1, WO 2017 / 148577 A1, and DE 102015223795 A1. An embodiment of a method for producing an optical component 100, 200 is explained in more detail below with reference to Fig. 12. In a first step S1, a simulation model is defined which comprises the optical component 100, 200. Relevant usage scenarios are initially selected. These consist of one or more illumination distributions and associated (dominant) mask structures, each of which defines a diffraction distribution according to reticle 7 (see Fig. 1). Based on a given source power and the transmittance of all optical elements – in particular those of the optical elements 102, 202 – in the light path 16 (see Fig.1) the locally variable irradiation intensity is determined for the respective optical element 102, 202. Based on the absorption behavior of the optical element 102, 202, which may be dependent on the angle of incidence, it is determined which power is absorbed locally in each case. In a second step S2, various designs of the optical component 100, 200, as illustrated, for example, in FIGS. 5 to 11, can now be mechanically and / or thermally modeled. For example, taking into account the irradiation history, a temperature distribution is determined in each variant, for which purpose a finite element simulation can be used, for example. Together with assumptions regarding the thermal expansion coefficients of the materials involved G. 102 , G 104A resulting change in refractive index and / or surface deformation is then calculated. The resulting aberration pattern or aberration level is determined using an optical calculation. The aberration level can be defined, for example, as an RMS ("root mean square") value of the wavefront or as a maximum of all decomposition coefficients of the wavefront according to Zernike functions up to order 100. In the simulation according to step S2, a manufacturing effort for the optical component 100, 200 can also be determined. This can include, for example, machine hours (e.g., on a milling machine), material costs, etc. In a step S3, for example, the simulated actual aberration level (here also referred to as the "actual property" or one of the "properties of the optical component") is compared with a target aberration level (here also referred to as the "target property").In particular, a simulated actual RMS value of the wavefront can be compared with a target RMS value of the wavefront. Furthermore, a simulated actual manufacturing effort can be compared with a target manufacturing effort. If either the simulated actual property does not correspond to the desired target property (e.g. the simulated actual RMS value is above a target RMS value) or the actual manufacturing effort is above the target manufacturing effort, steps S4 and S5 follow. Steps S4 and S5 can be carried out individually or optionally. The simulation model is adapted according to step S4. In particular, a dimension of the optical elements 102, 202 and / or the support elements 104, 204 is changed. Additionally or alternatively, for example, the first and / or second material G. 102 , G 104 In particular, if a desired target aberration is not yet achieved, the first material G 102For example, a material with improved refractive index homogeneity, a lower proportion and / or smaller size of inclusions, lower stress birefringence or a lower contrast loss, a specific intrinsic stress birefringence, higher transmittance, higher density or hardness or a lower change therein in at least one spatial direction, improved slumping properties, lower compaction or solarization can be used. Conversely, if the actual aberration is better than the target aberration, the optical quality of the second material can be reduced in order to reduce manufacturing costs and thus meet a manufacturing budget.As an example, a series of finishing manufacturing steps, such as pre-polishing to achieve a required surface quality, for example with regard to roughness, can be carried out only for the optical element 102, 202 or the first material G. 102carried out, but not for the support element 104, 204. This allows smaller tools to be used in production, the processing time is reduced, and smaller masses have to be handled during transport and clamping processes. This reduces the technical effort and often the scrap rate. Instead of adapting the simulation model according to step S4, it may be sufficient to provide suitable correction means in order to adapt the actual property to the target property. The addition of appropriate correction means can be designed in such a way that it only insignificantly increases the manufacturing effort. The correction means can include, for example, further optical elements that can be manipulated in rigid body degrees of freedom in the beam path before or after the optical element 102, 202. Furthermore, thermally influenceable optical parts, deformable mirrors, Alvarez elements, etc. can be provided in the beam path before and / or after the optical element 102, 202.This serves in particular to correct residual optical errors of the simulated projection exposure system 1 (or of another optical system). An example of such a correction means is the actuator 112 (see Fig. 2), which is designed to manipulate the position of the optical element 102 in space (see Fig. 2). If the actual aberration level corresponds to the target aberration level (or is lower) and the actual manufacturing effort is below the target manufacturing effort, i.e., within budget, the optical component 100, 102 is manufactured according to the simulated features in a step S6 (see Fig. 12). Fig. 13 shows a method step in the manufacture of the optical element 102 using a slumping process. Fig. 13 shows a section through a mold 300, and Fig. 14 shows a plan view XIV from Fig. 13. The production of the optical element 102 in the slumping process corresponds, for example, to the process step K1 shown in Fig.15.For this purpose, several layers 302 to 306 with layer thicknesses S are deposited on the mold 300. 302 to S 306for example, constructed from a glass substrate. The still soft layers 302 to 306 take the form of an outer (convex) contour 308 of the mold 300, so that the optically effective surface 106 is produced with the desired contour. The three layers 302 to 306 shown are purely exemplary. In reality, a multiple of such layers are produced. The support element 104 can also be produced using a (complex) slumping process. Alternatively, the support element 104 can be produced from a solid material without using a slumping process, for example by a material-removing process, such as milling and / or polishing. However, if the optical element 102 and the support element 104 are produced using a slumping process, this is preferably done in such a way that the respective actual layer thickness achieved (for example, the layer thicknesses S 302 to S 306 ) in the first material G 102(of the optical element 102) deviates maximally or on average less from the desired target layer thickness (specified, for example, in a CAD model of the optical element 102) than that of the non-illustrated layer thicknesses of the second material G 104 (of the support element 104). In particular, an actual layer thickness of the first material G 102 less than 10%, preferably less than 20% or more preferably less than 50% closer to the respective target layer thickness than the second material G 104Although the present invention has been described using exemplary embodiments, it is capable of being modified in many ways. LIST OF REFERENCE SYMBOLS 1 Projection exposure system 2 Illumination system 3 Light source 4 Illumination optics 5 Object field 6 Object plane 7 Reticle 8 Reticle holder 9 Reticle displacement drive 10 Projection optics 11 Image field 12 Image plane 13 Wafer 14 Wafer holder 15 Wafer displacement drive 16 Illumination radiation 17 Collector 18 Intermediate focal plane 19 Deflecting mirror 20 First facet mirror 21 First facet 22 Second facet mirror 23 Second facet 100 Optical component 102 Optical element 104 Support element 106 Optically effective surface 108 Bubble 110 Bubble 112 Actuator 114 Support frame 116 Interface 118 Solid-state joint 120 Pin 122 Longitudinal axis 124 Measurement object 126 Measurement beam 128 Interferometer 130 Sensor frame 132 Measuring arrangement 134 Back 136 Surface 138 Laser 140 Laser source 142 Circumferential surface 144 Side surface 145 Recess 146 Adhesive 148 Intermediate mount 150Screw 152 Foot 200 Optical component 202 Optical element 204 Supporting element 206 Optically effective surface 214 Supporting frame 242 Circumferential surface 245 Through opening 260 Socket 262 Working light 264 Page 266 Page 268 Exit surface 300 Forming tool 302 Layer 304 Layer 306 Layer 308 Contour α Angle A 104 Diagonal A 202 Diagonal D 102 Dimension D 204 Dimension H 102 Main extension level H 104 Main extension level H 202 Main extension level H 204 Main extension plane K1 to K3 Process steps M1 Mirror M2 Mirror M3 Mirror M4 Mirror M5 Mirror M6 Mirror S1 to S6 Process steps S 302 Layer thickness S 304 Layer thickness S 306 Layer thickness T 102 Thickness T 104 Thickness x, y, z spatial directions

Claims

PATENT CLAIMS 1. Optical component (100, 200) for a lithography system (1), comprising an optical element (102, 202) made of a first material (G 102 ) is manufactured and has an optically effective surface (106, 206); and a supporting element (104, 204) which is made of a second material (G 104 ) is manufactured and carries the optical element (102, 202), wherein the second material (G 104 ) from the first material (G 102 ) is different and a ratio of the densities ( ρ G102 , ρ G102 ) of the first and second material (G 102 , G 104 ) by less than 20%, preferably by less than 10%, and more preferably by less than 5% from 1; wherein the optical element (102, 202) and the support element (104, 204) each have a principal extension plane (H 102 , H 202 , H 104 , H 204 ) exhibit, in which they have a maximum extent, where the maximum extent (D102 , A 202 ) of the optical element (102, 202) less than 90%, preferably less than 80%, and even more preferably less than 75% of the maximum extent (A 104 , D 204 ) of the support element (104, 204); and wherein the optical element (102) has a side (134) facing away from the optically effective surface (106), wherein the side (134) has a side surface and the optical element (102) is in contact with the support element (104) over at least 50% of its side surface.

2. Optical component according to claim 1, wherein the optical element (102) and the support element (104) are each perpendicular to the principal extension plane (H). 102 , H 104 ) a maximum thickness (T 102 , T 104 ) exhibit the maximum thickness (T 102 ) of the optical element (102) less than 90%, preferably less than 80%, and more preferably less than 75% of the maximum thickness (T) 104 ) of the supporting element (104).

3. Optical component according to claim 1 or 2, wherein the optical element (102) is in contact with the support element (104) over at least 75% and more preferably over at least 90% of its side surface or entirely, preferably over its entire surface.

4. Optical component according to any one of the preceding claims, wherein the optical element (102) is received in a recess (145), in particular in a cup-shaped recess, or in a through-opening (245) in the support element (104, 204) and / or wherein a material boundary (142, 242) exists between the first and second material (G). 102 , G 104 ) partially or completely in one direction (z) perpendicular to the principal extension plane (H 102 , H 202) of the optical element (102).

5. Optical component according to any one of the preceding claims, wherein the optical element (102, 202) and the support element (104, 204) are formed in one piece and / or wherein the optical element (102, 202) and the support element (202, 204) are attached to one another by force, material, and / or form-fitting means.

6. Optical component according to any one of the preceding claims, wherein the optical element (102, 202) and the support element (104, 204) are fused, glued, or blasted together.

7. Optical component according to any one of the preceding claims, wherein the first and second materials (G 102 , G 104 ) differ in one or more of the following properties: refractive index homogeneity; a proportion and / or a size (D 108 , D 110 ) of inclusions, especially bubbles (108, 110); of stress birefringence; of intrinsic polarization birefringence; a transmittance, in particular at the operating wavelength of the optical element (102, 202); a density and / or a change in density in at least one spatial direction (x, y, z); a slumping property; a roughness; and a resistance to compaction and / or solarization.

8. Optical component according to one of the preceding claims, wherein at an expected mean operating temperature a coefficient of thermal expansion of the first material (G 102 ) is at least ten times lower than a thermal expansion coefficient of the second material (G 1049. Optical component according to any one of the preceding claims, wherein the support element (104, 204) comprises one or more of the following components: a mechanical interface (116) for attaching the same to a support frame (114) of a lithography system (1) and / or for attaching an actuator (112); and / or a measuring object (124) for measuring the position of the support element (104, 204) using a measuring device (128).

10. Optical component according to any one of the preceding claims, wherein the optical element (102, 202) is a mirror, a lens, a polarizing optical element, in particular a retarder plate, a polarizing filter or a rotating element configured to rotate a polarization direction, a color filter and / or an optical grating.

11. Optical component according to any one of the preceding claims, wherein the first material (G 102 ) Ultralow expansion material, Zerodur, calcium floride and / or quartz glass, and / or the second material (G 104) Quartz glass, optical glass, glass ceramic, silicon, SiSiC or steel, in particular Invar.

12. Use of the optical component (100, 200) according to any one of claims 1 to 11 in an imaging process, wherein a working light (16) used has a wavelength of less than 120 nm, preferably less than 30 nm.

13. Projection lens (10), in particular a catadioptric projection lens or with a pure mirror system, comprising an optical component (100, 200) according to any one of claims 1 to 11.

14. Lithography system (1), in particular an EUV or DUV lithography system, comprising an optical component (100, 200) according to any one of claims 1 to 11 or a projection lens (10) according to claim 13. 15.A method for manufacturing an optical component (100, 200) according to any one of claims 1 to 11, comprising the steps of: a) simulating (S2) properties of the optical component (100, 200) in operation; b) adjusting (S5) at least one of these properties as a function of the simulation; and c) manufacturing (S6) the optical component (100, 200) with the adjusted property.

16. A method according to claim 15, wherein: the properties of the optical component (100, 200) in operation according to step a) are simulated in a first simulation; a manufacturing effort for manufacturing the optical component (100, 200) is simulated in a second simulation; and. the adjustment of the at least one property according to step b) is carried out depending on the first and second simulations.

17. Method according to claim 15 or 16, wherein: the properties simulated according to step a) comprise an optical property of the optically effective surface (106, 206); and / or the adjustment of the at least one property according to step b) is an adjustment of a dimension (D 102 , A 104 , A 202 , D 204 ,) of the optical element (102, 202) and / or of the support element (104, 204) and / or an adaptation of the first and / or second material (G 102 , G 104) comprises; and / or a correction means (112) for adjusting at least one property of the optical element (102, 202) is determined, wherein the correction means (112) is provided outside the optical component (100).

18. Method for manufacturing an optical component (100, 200) for a lithography system (1), comprising the steps: a) Manufacturing (K1) an optical element (102, 202) from a first material (G 102 ) with an optically effective surface (106, 206); and b) manufacturing (K2) a supporting element (104, 204) from a second material (G 104 ), where the second material (G 104 ) from the first material (G 102 ) is different and a ratio of the densities (ρ G102 , ρ G102 ) of the first and second material (G 102 , G 104) by less than 20%, preferably by less than 10%, and more preferably by less than 5% from 1; c) Connecting (K3) the optical element (102, 202) to the support element (104, 204) such that the support element (104, 204) supports the optical element (102, 202), wherein the optical element (102, 202) and the support element (104, 204) each have a principal extension plane (H 102 , H 202 , H 104 , H 204 ) exhibit, in which they have a maximum extent, where the maximum extent (D 102 , A 202 ) of the optical element (102, 202) less than 90%, preferably less than 80% and even more preferably less than 75% of the maximum extent (A 104 , D 204 ) of the supporting element (104, 204).

19. Method according to claim 18, wherein in step a) a variation of a removal rate with which the first material (G 102) is removed, is greater than 20% and / or in step b) a variation in the removal rate with which the second material (G 104 ) is removed, is less than or equal to 20%.

20. Method according to claim 18 or 19, wherein the manufacturing in step a) and / or step b) comprises the application of a slumping process, wherein preferably a maximum or mean deviation of an actual layer thickness from a target layer thickness is smaller for the first material than for the second material.

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