MANIPULATOR, OPTICAL SYSTEM AND PROJECTION LIGHTING SYSTEM

Abstract

A manipulator (134, 136) for adjusting an optical element (102, 102') of a projection exposure system (1), comprising a magnet assembly (144) that can be coupled to the optical element (102, 102'), a coil assembly (148) by means of which the magnet assembly (144) can be linearly displaced in order to adjust the optical element (102, 102'), and a shield (200A, 200B, 200C) for magnetically shielding the magnet assembly (144) and the coil assembly (148) from external magnetic interference fields, wherein the magnet assembly (144) and the coil assembly (148) are at least partially enclosed by the shield (200A, 200B, 200C).

Description

[0001] The present invention relates to a manipulator for adjusting an optical element of a projection exposure apparatus, an optical system comprising such a manipulator and a projection exposure apparatus comprising such a manipulator and / or such an optical system.

[0002] Microlithography is used to manufacture microstructured components, such as integrated circuits. The microlithography process is carried out using a lithography system equipped with 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 to the light-sensitive coating of the substrate.

[0003] Driven by the pursuit of ever smaller structures in the production 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. Due to the high absorption of light at this wavelength by most materials, such EUV lithography systems require the use of reflective optics, i.e., mirrors, instead of the previously used refractive optics, i.e., lenses.

[0004] During exposure operation of such an EUV lithography system, it is necessary to adjust the mirrors of the projection system. Manipulators, particularly so-called voice coil manipulators (VCMs), can be used for this purpose. Such a manipulator forms a spring-mass-damper system that decouples the mirror from a fixed world, in particular from a support frame (force frame). Using several such manipulators, it is possible to adjust the mirror in six degrees of freedom.

[0005] To achieve higher scan speeds and thus higher throughput of the EUV lithography system, it is necessary to accelerate the movements of the reticle and substrate using a reticle translation drive and a wafer translation drive. This requires higher magnetic fields, which interact undesirably with the manipulators, especially with the magnetic fields of the manipulators. In particular, this can lead to disturbing forces that can negatively impact the LoS (Line of Sight) budget of the projection system and the manipulators.

[0006] In particular, crosstalk can occur between the magnetic fields of the reticle translation drive or the wafer translation drive and the magnetic fields of the manipulators. For example, a movement of the reticle translation drive or the wafer translation drive can cause blurring of an image projected from the reticle onto the substrate. Neighboring manipulators can also cause such undesirable effects. This needs to be improved.

[0007] Against this background, an object of the present invention is to provide an improved manipulator for adjusting an optical element.

[0008] Accordingly, a manipulator for adjusting an optical element of a projection exposure system is proposed. The manipulator comprises a magnet assembly that can be coupled to the optical element, a coil assembly with the aid of which the magnet assembly can be linearly displaced to adjust the optical element, and a shield for magnetically shielding the magnet assembly and the coil assembly from external magnetic interference fields, wherein the magnet assembly and the coil assembly are at least partially enclosed by the shield.

[0009] Because the shield shields the magnet assembly and the coil assembly from external magnetic interference fields, it prevents these external magnetic interference fields from influencing the manipulator in an undesirable way, thus avoiding or at least reducing the effects explained above. In particular, the shield can also be used to direct the manipulator's magnetic fields, allowing the manipulator's actuating force to be increased. This enhances the manipulator's performance.

[0010] The manipulator can also be referred to as an actuator, actuating element, or actuating device. Preferably, two manipulators each form a manipulator arrangement. The optical element can be a mirror, in particular an EUV mirror. However, the optical element can also be a lens. Preferably, however, the optical element is a mirror and comprises a substrate and an optically effective surface attached to the substrate. The optically effective surface is configured to reflect illumination radiation, in particular EUV radiation. The optically effective surface can be a mirror surface.

[0011] The manipulator can be assigned a coordinate system with a first spatial direction or x-direction, a second spatial direction or y-direction, and a third spatial direction or z-direction. The spatial directions are oriented perpendicular to each other. The optical element or optically effective surface has six degrees of freedom, namely three translational degrees of freedom along the x-direction, the y-direction, and the z-direction, as well as three rotational degrees of freedom about the x-direction, the y-direction, and the z-direction. This means that the position and orientation of the optical element or optically effective surface can be determined or described using the six degrees of freedom.

[0012] The "position" of the optical element or optically effective surface refers in particular to its coordinates or the coordinates of a measuring point provided on the optical element with respect to the x-direction, the y-direction, and the z-direction. The "orientation" of the optical element or optically effective surface refers in particular to its tilt with respect to the three spatial directions. This means that the optical element or optically effective surface can be tilted about the x-direction, the y-direction, and / or the z-direction.

[0013] This results in six degrees of freedom for the position and / or orientation of the optical element or optically effective surface. A "position" of the optical element or optically effective surface preferably encompasses both its position and its orientation. The term "position" can therefore be replaced by the phrase "position and orientation," and vice versa.

[0014] "Adjusting" or "aligning" the optical element or the optically effective surface refers, in particular, to changing the position of the optical element or the optically effective surface. For example, the optical element can be moved from an actual position to a desired position and vice versa using several such manipulators. For this purpose, six manipulators, for example, can be provided, which can in particular be grouped in pairs to form manipulator arrangements. The adjustment or alignment of the optical element or the optically effective surface can thus take place in all six aforementioned degrees of freedom.

[0015] The magnet assembly preferably comprises at least one magnet or a plurality of magnets, in particular permanent magnets. However, reference will be made below to only one magnet. The magnet assembly further comprises a magnet assembly housing to which the magnet is attached. The magnet assembly housing can be tubular, wherein the magnet can be arranged on the outside of the magnet assembly housing. The magnet assembly can preferably be coupled to the optical element using its magnet assembly housing. To couple the magnet assembly or the magnet assembly housing to the optical element, a manipulator pin can be provided, which is coupled to both the optical element and the magnet assembly housing.

[0016] The fact that the magnet assembly is "coupleable" to the optical element means, in particular, that the magnet assembly can be firmly connected to the optical element, for example, with the aid of the magnet assembly housing and the manipulator pin. For this purpose, the optical element preferably has a plurality of mirror bushings provided on the rear side of the optical element, facing away from the optically active surface. For example, three such mirror bushings are provided. Preferably, two such manipulators are coupled to each mirror bushing, each in the form of a manipulator arrangement as mentioned above.

[0017] The coil assembly preferably comprises at least one coil configured to interact with the magnet assembly, in particular with the magnet of the magnet assembly. Preferably, multiple coils are provided. In particular, at least two coils are provided. However, only one coil will be discussed below. So-called Lorentz forces act between the coil and the magnet. Therefore, the manipulator can also be referred to as a Lorentz force manipulator. During operation of the manipulator, the coil assembly interacts with the magnet assembly, causing the magnet assembly to move linearly or translationally along a direction of movement relative to the coil assembly. This movement is applied to the optical element in order to adjust it.The fact that the magnet assembly is “linearly displaceable” with the aid of the coil assembly means in this case that the magnet assembly can move along a straight line relative to the coil assembly during operation of the manipulator.

[0018] An "external magnetic interference field" is understood here to mean a magnetic field of an assembly different from the manipulator. This assembly can be, for example, a reticle displacement drive, a wafer displacement drive, and / or another manipulator. "Shielding" is understood here in particular to mean that the shield is designed to deflect or redirect the external magnetic interference fields so that they have no or only a reduced influence on the magnet assembly and / or the coil assembly.

[0019] The shield is preferably a pot-shaped or cylindrical component. The shield encloses an interior space within which the magnet assembly and the coil assembly are arranged. The shield can also be referred to as a shielding shield, in particular a magnetic shielding shield. As previously mentioned, the shield encloses or encapsulates the magnet assembly and the coil assembly.

[0020] The fact that the shield "at least partially encloses" the magnet assembly and the coil assembly is to be understood in this case to mean that the magnet assembly and the coil assembly are partially arranged within the shield. However, this does not preclude the magnet assembly and / or the coil assembly from also being arranged at least partially outside the shield. For example, the magnet assembly protrudes from the shield to allow adjustment of the optical element.

[0021] According to one embodiment, the manipulator has a manipulator housing which is at least partially enclosed by the shield, wherein the manipulator housing is at least partially led out of the shield.

[0022] The manipulator housing is arranged, in particular, within the interior space enclosed by the shield. The shield thus encloses or encapsulates the manipulator housing. However, this does not preclude parts of the manipulator housing from protruding from the shield. This may be necessary, for example, to connect the manipulator housing to a fixed world, for example in the form of a force frame. For this purpose, the manipulator housing is led out of the shield at least in sections and connected to the fixed world at one or more connection points. In this case, a "connection point" is not to be understood as a point in the geometric sense, but rather as an area or component by means of which the manipulator, in particular the manipulator housing, is connected to the fixed world.For example, such a connection point can comprise one or more screw connections. Furthermore, any number of connection points can be provided. To lead the manipulator housing out of the shield, the shield preferably has openings. In this context, an "opening" can be understood, for example, as a perforation, a bore, a cutout, a recess, a groove, or the like provided in the shield. The shield preferably has a thinner wall than the manipulator housing. In particular, the shield has a constant or consistent wall thickness.

[0023] According to a further embodiment, the manipulator housing has a fastening web which is led out of the shield through an opening provided in the shield.

[0024] The manipulator housing can have any number of mounting bars. Accordingly, the shield can also have multiple openings. The number of openings corresponds to the number of mounting bars. The manipulator housing is coupled to the fixed world by means of the mounting bar. The mounting bar extends from the interior of the shield through the shield and out of it, connecting the manipulator housing to the fixed world. The mounting bar is thus connected to the fixed world by means of the previously mentioned connection point.

[0025] According to a further embodiment, the magnet assembly and the coil assembly are at least partially enclosed by the manipulator housing.

[0026] Accordingly, the magnet assembly and the coil assembly are at least partially enclosed or encapsulated by the manipulator housing, with the manipulator housing in turn being at least partially enclosed by the shield. Furthermore, the magnet assembly can be arranged at least partially within the coil assembly.

[0027] According to a further embodiment, the shield is mechanically decoupled from the manipulator housing.

[0028] "Mechanically decoupled" in this case means that no forces can be transferred from the manipulator, in particular from the manipulator housing, to the shield or vice versa. This is achieved by not rigidly connecting the shield to the manipulator housing, but rather connecting the shield directly to the fixed world. The manipulator housing, in particular the mounting bar, is led out of the interior of the shield through the aforementioned opening without contacting the shield and is separately connected to the fixed world.

[0029] According to a further embodiment, the magnet assembly is led out of the shield at least in sections in order to adjust the optical element.

[0030] To extend the magnet assembly at least partially out of the shield, the shield has an opening, particularly in the form of a bore or aperture. The opening can be provided in a cover section of the shield. In particular, the aforementioned manipulator pin of the magnet assembly extends out of the shield. The manipulator pin is coupled to the optical element.

[0031] According to a further embodiment, the shield is constructed rotationally symmetrically to an axis of symmetry.

[0032] The shield can, in particular, be cylindrical or pot-shaped. The shield can, for example, be manufactured as a welded assembly. For example, a base section of the shield and the aforementioned cover section can be welded together. Screw connections can also be used to produce the shield. The shield can also be a deep-drawn component. In this case, the shield can form a one-piece component, in particular a component made of a single material. "One-piece" or "one-piece" in the present case means, in particular, that the shield is not composed of several subcomponents, but forms a continuous component. "One-piece material" in the present case means, in particular, that the shield is made entirely of the same material. The shield can also be manufactured using machining processes such as turning, milling, and / or eroding.Furthermore, additive or generative manufacturing processes, in particular 3D printing processes, can also be used to produce the sign.

[0033] According to a further embodiment, the shield has a tubular base portion which encloses the magnet assembly and the coil assembly at least in sections.

[0034] The base section is designed to be rotationally symmetrical to the axis of symmetry. The base section encloses the interior of the sign. The base section can be closed at the front using the aforementioned cover section and a base section. However, the cover section and base section are optional.

[0035] According to a further embodiment, the base portion has a mounting flange for attaching the sign to a fixed world.

[0036] As previously mentioned, the fixed world can be a supporting frame. The mounting flange can completely encircle the axis of symmetry. The mounting flange can be annular. However, the mounting flange can also not completely encircle the axis of symmetry. In this case, the mounting flange is interrupted. The mounting flange can have openings through which fastening elements, in particular screws, can be passed to connect the base section and thus the shield to the fixed world.

[0037] According to a further embodiment, the shield has a cover section and / or a base section for closing the base section at the front.

[0038] For example, the shield can have only the cover section, only the base section, or both the cover section and the base section. In this case, either at least the cover section or at least the base section can be removed from the shield. This allows adjustment work to be carried out on the manipulator. For example, the cover section and / or the base section can be screwed to the base section. However, welded or soldered connections are also possible.

[0039] According to a further embodiment, the shield is made of a metallic material, in particular of an iron-nickel alloy, with a magnetic permeability µ r manufactured from 20,000 to 200,000.

[0040] The magnetic permeability µ determines the ability of materials to adapt to a magnetic field. More precisely, the magnetic permeability µ determines the magnetization of a material in an external magnetic field. The magnetic permeability µ therefore determines the permeability of material to magnetic fields. The higher the magnetic permeability µ r The higher the thickness, the less permeable the material is to magnetic fields. For example, the FeNi48 alloy can be used for the shield. The shield is made of a ferromagnetic material.

[0041] According to a further embodiment, the shield is coated with an anti-corrosive coating, in particular with a nickel-phosphorus coating.

[0042] In particular, the shield can be coated with the coating both inside and outside. Annealing and / or lime hardening processes during shield manufacture are preferably carried out in such a way that the magnetic permeability of the shield is not negatively affected.

[0043] Furthermore, an optical system for a projection exposure system is proposed. The optical system comprises an optical element and a manipulator as previously explained, wherein the magnet assembly is coupled to the optical element.

[0044] For example, the magnet assembly is firmly connected to the optical element via the manipulator pin. The optical system can have a plurality of such optical elements. The optical elements are preferably mirrors. However, the optical elements can also be lenses. The optical system can be a projection optics unit or part of a projection optics unit of the projection exposure system. The optical system can therefore also be referred to as a projection optics unit or a projection lens. Alternatively, the optical system can also be an illumination optics unit or part of such an illumination optics unit. In the present case, however, it is assumed that the optical system is a projection optics unit as mentioned above or part of such a projection optics unit. The optical system preferably comprises a plurality of manipulators.

[0045] According to one embodiment, the optical system has a fixed world, wherein the manipulator has a manipulator housing which is at least partially enclosed by the shield, wherein the manipulator housing is connected to the fixed world, and wherein the shield is connected to the fixed world.

[0046] As previously mentioned, the fixed world can be a support frame of the optical system. The optical element is coupled to the fixed world by means of the manipulator. The manipulator housing is rigidly connected to the fixed world. For this purpose, the manipulator housing can be connected to the fixed world, for example, with a fastening web as previously mentioned, which extends from the shield. The manipulator housing can be screwed to the fixed world. Furthermore, the shield can also be screwed to the fixed world. The shield can be connected to the fixed world, in particular, by means of its previously mentioned fastening flange.

[0047] Furthermore, a projection exposure system with a manipulator as explained above and / or an optical system as explained above is proposed.

[0048] The optical system is preferably a projection optics unit of the projection exposure system. However, the optical system can also be an illumination optics unit. The projection exposure system can be an EUV lithography system. EUV stands for "Extreme Ultraviolet" and refers to a wavelength of the working light between 0.1 nm and 30 nm. The projection exposure system can also be a DUV lithography system. DUV stands for "Deep Ultraviolet" and refers to a wavelength of the working light between 30 nm and 250 nm.

[0049] "One" in this case is not necessarily limited to a single element. Rather, multiple elements, such as two, three, or more, may also be included. 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 otherwise stated.

[0050] The embodiments and features described for the manipulator apply accordingly to the proposed optical system and the proposed projection exposure system and vice versa.

[0051] Further possible implementations of the invention also include combinations of features or embodiments described above or below with respect to the exemplary embodiments that are not explicitly mentioned. 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.

[0052] Further advantageous embodiments and aspects of the invention are the subject of the dependent claims and the exemplary embodiments of the invention described below. The invention will be explained in more detail below using preferred embodiments with reference to the accompanying figures. Fig. 1 shows a schematic meridional section of a projection exposure system for EUV projection lithography; Fig. 2 shows a schematic view of an embodiment of an optical system for the projection exposure apparatus according to Fig. 1; Fig. 3 shows a schematic plan view of the optical system according to Fig. 2; Fig. 4 shows a schematic sectional view of an embodiment of a manipulator for the optical system according to Fig. 2; Fig. Figure 5 shows a schematic perspective view of an embodiment of a shield for the manipulator according to Fig. 4; and Fig. 6 shows a schematic perspective exploded view of another embodiment of a shield for the manipulator according to Fig. 4.

[0053] In the figures, identical or functionally equivalent elements are provided with the same reference numerals unless otherwise indicated. Furthermore, it should be noted that the representations in the figures are not necessarily to scale.

[0054] 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, an 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 remaining illumination system 2. In this case, the illumination system 2 does not include the light source 3.

[0055] 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 via a reticle displacement drive 9, in particular in a scanning direction.

[0056] In the Fig. For illustrative purposes, Figure 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 to the plane of the drawing. The y-direction y runs horizontally, and the z-direction z runs vertically. The scanning direction runs in the Fig. 1 along the y-direction y. The z-direction z runs perpendicular to the object plane 6.

[0057] The projection exposure system 1 comprises a projection optics 10. The projection optics 10 serves 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.

[0058] A structure on the reticle 7 is imaged onto a light-sensitive layer of a wafer 13 arranged in the image plane 12 in the region of the image field 11. 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 displacement of the wafer 13, on the other hand, via the wafer displacement drive 15, can be synchronized with each other.

[0059] 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).

[0060] The illumination radiation 16 emanating from the light source 3 is focused 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.

[0061] 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.

[0062] 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 conjugated 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. Of these first facets 21, Fig. 1 only some examples are shown.

[0063] 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.

[0064] As is known, for example, from DE 10 2008 009 600 A1, the first facets 21 themselves can 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 10 2008 009 600 A1.

[0065] Between the collector 17 and the deflecting mirror 19, the illumination radiation 16 runs horizontally, i.e. along the y-direction y.

[0066] 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 1 614 008 B1, and US Pat. No. 6,573,978.

[0067] 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.

[0068] The second facets 23 can also be macroscopic facets, which can, for example, be round, rectangular, or hexagonal, or alternatively facets composed of micromirrors. Reference is also made to DE 10 2008 009 600 A1 in this regard.

[0069] The second facets 23 can have planar or alternatively convex or concave curved reflection surfaces.

[0070] The illumination optics 4 thus form a double-faceted system. This basic principle is also known as a fly's-eye integrator.

[0071] It may be advantageous to arrange the second facet mirror 22 not 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 arranged tilted relative to a pupil plane of the projection optics 10, as described, for example, in DE 10 2017 220 586 A1.

[0072] With the help 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 beam-forming mirror or actually the last mirror for the illumination radiation 16 in the beam path before the object field 5.

[0073] 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 into 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, grazing incidence mirrors).

[0074] The illumination optics 4 has in the version shown in the Fig. 1, after the collector 17 there are exactly three mirrors, namely the deflection mirror 19, the first facet mirror 20 and the second facet mirror 22.

[0075] In a further embodiment of the illumination optics 4, the deflection 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.

[0076] 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 usually only an approximate imaging.

[0077] 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.

[0078] In the Fig. In the example shown in Figure 1, the projection optics 10 comprises six mirrors M1 to M6. Alternatives with four, eight, ten, twelve, or a different number of mirrors M1 are also possible. The projection optics 10 is a doubly obscured optic. 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, for example, 0.7 or 0.75.

[0079] 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, 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.

[0080] The projection optics 10 has 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.

[0081] The projection optics 10 can, in particular, be anamorphic. It has, in particular, different magnifications Bx, By in the x and y directions x, y. The two magnifications Bx, By of the projection optics 10 are preferably (ßx, By) = (+ / - 0.25, + / - 0.125). A positive magnification B means imaging without image inversion. A negative sign for the magnification B means imaging with image inversion.

[0082] The projection optics 10 thus leads to a reduction in the ratio 4:1 in the x-direction x, i.e. in the direction perpendicular to the scanning direction.

[0083] The projection optics 10 leads to a reduction of 8:1 in the y-direction y, i.e. in the scanning direction.

[0084] Other magnifications are also possible. Magnifications 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.

[0085] 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 can be different, depending on the design of the projection optics 10. 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.

[0086] 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, in particular, result in illumination according to the Köhler principle. The far field is divided into a plurality of object fields 5 using the first facets 21. The first facets 21 generate a plurality of images of the intermediate focus on the second facets 23 assigned to them.

[0087] The first facets 21 are each imaged onto the reticle 7 by an associated 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.

[0088] 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 the illumination setting or illumination pupil fill.

[0089] 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.

[0090] 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.

[0091] The projection optics 10 can, in particular, have a homocentric entrance pupil. This can be accessible. It can also be inaccessible.

[0092] The entrance pupil of the projection optics 10 cannot usually be precisely illuminated with the second facet mirror 22. When imaging the projection optics 10, which telecentrically images the center of the second facet mirror 22 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 conjugate to it in spatial space. In particular, this surface exhibits a finite curvature.

[0093] It is possible that the projection optics 10 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 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.

[0094] In the Fig. In the arrangement of the components of the illumination optics 4 shown in Figure 1, the second facet mirror 22 is arranged in a surface conjugate to the entrance pupil of the projection optics 10. The first 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 deflection mirror 19. The first facet mirror 20 is arranged tilted relative to an arrangement plane defined by the second facet mirror 22.

[0095] Fig. 2 shows a schematic view of an embodiment of an optical system 100 for the projection exposure apparatus 1. Fig. 3 shows a schematic plan view of the optical system 100. The following refers to the Fig. 2 and Fig. 3 simultaneously referred to.

[0096] The optical system 100 can be a projection optics unit 10 as explained above or part of such a projection optics unit 10. Therefore, the optical system 100 can also be referred to as a projection optics unit. However, the optical system 100 can also be an illumination system 2 as explained above or part of such an illumination system 2. Therefore, the optical system 100 can alternatively also be referred to as an illumination system. However, it is assumed below that the optical system 100 is a projection optics unit 10 or part of such a projection optics unit 10. The optical system 100 is suitable for EUV lithography. However, the optical system 100 can also be suitable for DUV lithography.

[0097] The optical system 100 may comprise a plurality of optical elements 102, of which Fig. 2 and Fig. 3, however, only one is shown. Therefore, only one optical element 102 will be discussed below. The optical element 102 can be one of the mirrors M1 to M6. The optical element 102 comprises a substrate 104 and an optically effective surface 106, for example, a mirror surface. The substrate 104 can also be referred to as a mirror substrate. The substrate 104 can comprise glass, ceramic, glass-ceramic, or other suitable materials.

[0098] The optically effective surface 106 is provided on a front side 108 of the substrate 104. The optically effective surface 106 can be realized by means of a coating applied to the front side 108. The optically effective surface 106 is a mirror surface. The optically effective surface 106 is suitable for reflecting illumination radiation 16, in particular EUV radiation, during operation of the optical system 100. The optically effective surface 106 can be shown in plan view according to Fig. 3 may have an oval or elliptical geometry. The optical element 102 or the substrate 104 may have a triangular geometry. In principle, however, the geometry is arbitrary.

[0099] Facing away from the optically effective surface 106 or the front side 108, the optical element 102 has a rear side 110. The rear side 110 has no defined optical properties. This means, in particular, that the rear side 110 is not a mirror surface and therefore does not have any reflective properties.

[0100] On the rear side 110, a plurality of mirror bushings 112, 114, 116 are provided. A first mirror bushing 112, a second mirror bushing 114, and a third mirror bushing 116 are provided. In other words, the optical element 102 comprises exactly three mirror bushings 112, 114, 116. The mirror bushings 112, 114, 116 can be geometrically identical. The mirror bushings 112, 114, 116 are cylindrical and extend in the orientation of the Fig. 2 protrudes from the underside of the rear panel 110. The mirror sockets 112, 114, 116 form the corners of an imaginary triangle.

[0101] The optical element 102 or the optically effective surface 106 has six degrees of freedom, namely three translational degrees of freedom along the first spatial direction or x-direction x, the second spatial direction or y-direction y, and the third spatial direction or z-direction z, as well as three rotational degrees of freedom about the x-direction x, the y-direction y, and the z-direction z. This means that a position and an orientation of the optical element 102 or the optically effective surface 106 can be determined or described using the six degrees of freedom.

[0102] The "position" of the optical element 102 or the optically effective surface 106 is to be understood in particular as its coordinates or the coordinates of a measuring point provided on the optical element 102 with respect to the x-direction x, the y-direction y, and the z-direction z. The "orientation" of the optical element 102 or the optically effective surface 106 is to be understood in particular as its tilt with respect to the three spatial directions x, y, z. This means that the optical element 102 or the optically effective surface 106 can be tilted about the x-direction x, the y-direction y, and / or the z-direction z.

[0103] This results in six degrees of freedom for the position and / or orientation of the optical element 102 or the optically effective surface 106. A "position" of the optical element 102 or the optically effective surface 106 encompasses both its position and its orientation. The term "position" can therefore be replaced by the phrase "position and orientation," and vice versa.

[0104] In the Fig. 2, solid lines depict an actual position IL of the optical element 102 and the optically effective surface 106, and dashed lines and the reference numerals 102' and 106' depict a desired position SL of the optical element 102 and the optically effective surface 106. The optical element 102 can be moved from its actual position IL to the desired position SL and vice versa. For example, the optical element 102 in the desired position SL meets certain optical specifications or requirements that the optical element 102 in the actual position IL does not meet.

[0105] In order to move the optical element 102 from the actual position IL to the desired position SL, the optical system 100 comprises an adjustment device 118. The adjustment device 118 is configured to adjust the optical element 102. In the present case, "adjusting" or "aligning" is understood to mean, in particular, changing the position of the optical element 102. For example, the optical element 102 can be moved from the actual position IL to the desired position SL and vice versa with the aid of the adjustment device 118. The adjustment or alignment of the optical element 102 can thus be carried out with the aid of the adjustment device 118 in all six aforementioned degrees of freedom.

[0106] The adjustment device 118 comprises several manipulator arrangements 120, 122, 124, which are arranged in the Fig. 2 are shown only very schematically. The manipulator arrangements 120, 122, 124 can also be referred to as actuator arrangements. Each mirror bushing 112, 114, 116 is assigned a manipulator arrangement 120, 122, 124. This means, in particular, that exactly three manipulator arrangements 120, 122, 124 are provided. Each manipulator arrangement 120, 122, 124 can be assigned two of the aforementioned degrees of freedom. With the three manipulator arrangements 120, 122, 124, an adjustment of the optical element 102 in all six degrees of freedom is thus possible.

[0107] A first manipulator assembly 120 is assigned to the first mirror bushing 112. A second manipulator assembly 122 is assigned to the second mirror bushing 114. A third manipulator assembly 124 is assigned to the third mirror bushing 116. The manipulator assemblies 120, 122, and 124 are identical in structure. Therefore, only the first manipulator assembly 120 and the first mirror bushing 112 will be discussed below, which will be referred to simply as the manipulator assembly 120 and the mirror bushing 112. All subsequent statements regarding the manipulator assembly 120 apply to the manipulator assemblies 122, 124, and vice versa.

[0108] The manipulator assembly 120 is coupled to the mirror socket 112 via a connection point 126. Furthermore, the manipulator assembly 120 is coupled to a fixed world 132 via two additional connection points 128, 130. The fixed world 132 can be a support frame (force frame) or another immovable structure.

[0109] The manipulator arrangement 120 has two manipulators 134, 136. The six degrees of freedom of the optical element 102 can be adjusted with the aid of all manipulators 134, 136 of all manipulator arrangements 120, 122, 124. The manipulators 134, 136 can also be referred to as adjusting elements, actuators, or actuators. In particular, the manipulators 134, 136 are so-called voice coil manipulators (VCM) or voice coil actuators (VCA) or can be referred to as such. In particular, the manipulators 134, 136 can be Lorentz force manipulators or can be referred to as such. The manipulators 134, 136 can be identical or different in design. The manipulators 134, 136 can be referred to in particular as mirror manipulators.

[0110] Both manipulators 134, 136 are connected to the mirror socket 112 at the connection point 126. Furthermore, the manipulators 134, 136 are connected to the fixed world 132 via the connection points 128, 130. The manipulators 134, 136 can be controlled by a control and regulation unit 138 of the adjustment device 118 to adjust the optical element 102. All manipulators 134, 136 of all manipulator arrangements 120, 122, 124 are operatively connected to the control and regulation unit 138, so that the control and regulation unit 138 can adjust the optical element 102 in all six degrees of freedom by appropriately controlling the manipulators 134, 136. This can be done based on sensor signals from a sensor system (not shown), which can detect the actual position IL and the desired position SL of the optical element 102.

[0111] Fig. 4 shows a schematic sectional view of an embodiment of a manipulator 134 as mentioned above.

[0112] The manipulators 134, 136 can be identical or differently constructed. Only the manipulator 134 will be discussed below. The manipulator 134 comprises a manipulator housing 140, which is connected to the fixed world 132. For example, the manipulator housing 140 can be connected to the fixed world 132 at the connection point 128. For example, the manipulator housing 140 can be screwed to the fixed world 132 at the connection point 128 using a fastening web 142. Particularly preferably, not just one connection point 128 is provided, but rather several connection points 128 are provided for connecting the manipulator housing 140 to the fixed world 132. Accordingly, several fastening webs 142 are also provided.

[0113] In addition to the manipulator housing 140, the manipulator 134 includes a magnet assembly 144. The magnet assembly 144 is at least partially located within the manipulator housing 140 (not shown). The magnet assembly 144 includes a tubular magnet assembly housing and a plurality of magnets attached to the outside of the magnet assembly housing. The magnets can be permanent magnets. A manipulator pin is connected to the magnet assembly housing, which in turn is coupled to the mirror bushing 112 via the connection point 126. The manipulator pin runs along the z-direction z.

[0114] The magnet assembly 144 is coupled to a coil assembly 148 via a spring element 146. The coil assembly 148 is arranged at least partially within the manipulator housing 140 (not shown). The magnet assembly 144 extends at least partially within the coil assembly 148. The coil assembly 148 comprises a coil. The spring element 146 can be a leaf spring. The magnet assembly housing of the magnet assembly 144 is connected to the coil assembly 148 by means of the spring element 146.

[0115] The magnet assembly 144 is further connected to the optical element 102 by means of a spring element 150. The spring element 150 can be part of the previously mentioned manipulator pin. In particular, the Fig. The spring element 150 shown in Figure 4 may be the manipulator pin that couples the magnet assembly 144 to the optical element 102. This means, in particular, that the spring element 150 may be part of the magnet assembly 144. The spring element 150 may be a leaf spring element.

[0116] The coil assembly 148 can rotate in a ring around the magnet assembly housing of the magnet assembly 144. The magnet assembly housing is thus passed through the coil assembly 148. The coil assembly 148 can move relative to the magnet assembly housing or vice versa.

[0117] The coil assembly 148 is connected to the manipulator housing 140 by means of a spring element 152. The spring element 152 can be a leaf spring element. Furthermore, the coil assembly 148 is coupled to the manipulator housing 140 by means of a damper 154. The damper 154 can be implemented as an eddy current brake. The coil assembly 148, the spring element 152, and the damper 154 form a spring-mass-damper system 156 of the manipulator 134.

[0118] During operation of the manipulator 134, Lorentz forces act between the coil assembly 148 and the magnet assembly 144, as indicated by an arrow 158. The manipulator pin connected to the magnet assembly housing thereby moves in a direction of movement 160 oriented along the z-direction z or along the manipulator pin extending along the z-direction z.

[0119] The directions of movement 160 of the two manipulators 134, 136 of the manipulator arrangement 120 differ from one another, so that the two directions of movement 160 are oriented obliquely to one another at an inclination angle. The inclination angle can be 60°. This allows a deflection of the optical element 102 and thus, through the interaction of the manipulator arrangements 120, 122, 124, an adjustment of the optical element 102 as previously explained. Reference will again be made below to only one manipulator 134.

[0120] For higher scanning speeds and thus a higher throughput of the projection exposure system 1, it is necessary to accelerate the movements of the reticle 7 and the wafer 13 using the reticle displacement drive 9 and the wafer displacement drive 15. This requires higher magnetic fields, which interact undesirably with the manipulator 134, particularly with the magnetic fields of the manipulator 134. In particular, this can lead to disruptive forces that can negatively impact the LoS (Line of Sight) budget of the optical system 100 and the manipulator 134.

[0121] In particular, so-called crosstalk can occur between the magnetic fields of the reticle displacement drive 9 or the wafer displacement drive 15 and the magnetic fields of the manipulator 134. For example, a movement of the reticle displacement drive 9 or the wafer displacement drive 15 can cause blurring of an image projected from the reticle 7 onto the wafer 13. This results from the fact that the reticle displacement drive 9 and / or the wafer displacement drive 15 are energized, causing them to move. The result is a changing electromagnetic interference field. This affects the manipulator 134 and is transferred to the optical element 102, thus leading to positioning errors and so-called surface figure deformation (SFD). This can result in imaging errors on the wafer 13 that cannot be corrected.Manipulators (not shown) arranged adjacent to the manipulator 134 can also cause such undesirable effects.

[0122] To prevent or at least reduce the aforementioned effects, a shield or shield 200A is assigned to the manipulator 134, which is suitable for shielding the manipulator 134 from external magnetic interference fields. The shield 200A concentrates field lines of the design of the manipulator 134, so that the manipulator 134 is no longer sensitive to external magnetic interference fields. The aforementioned effects are avoided or at least reduced. This also increases the performance of the manipulator 134. In particular, the shield 200A is also suitable for directing magnetic fields of the coil assembly 148, so that an actuating force of the manipulator 134 for actuating the optical element 102 can be increased.

[0123] The shield 200A encloses the manipulator 134 at least in sections. This means, in particular, that parts of the manipulator 134 can be arranged inside the shield 200A, and parts of the manipulator 134 can be arranged outside the shield 200A. The manipulator 134 can also be placed entirely inside the shield 200A. The shield 200A encloses or encapsulates the manipulator 134 at least in sections. The shield 200A can be part of the manipulator 134. However, this is not mandatory.

[0124] For example, the coil assembly 148 is placed entirely within the shield 200A, whereby the magnet assembly 144 can protrude at least partially from the shield 200A to actuate the optical element 102. For example, the manipulator pin of the magnet assembly 144 extends out of the shield 200A. The manipulator housing 140 also protrudes at least partially from the shield 200A so that the manipulator housing 140 can be connected to the fixed world.

[0125] The shield 200A is constructed rotationally symmetrically with respect to a central or symmetry axis 202, to which the manipulator 134 can also be constructed substantially rotationally symmetrically. The shield 200A encloses an interior space 204 within which the manipulator 134 or parts of the manipulator 134 are arranged. The shield 200A has an inner side 206 facing the interior space 204 and an outer side 208 facing away from the inner side 206.

[0126] The shield 200A has a tubular base section 210 that encloses the interior space 204. The base section 210 is constructed rotationally symmetrically to the axis of symmetry 202. The base section 210 includes a mounting flange 212, by means of which the base section 210 is connected to the fixed world 132. For this purpose, the mounting flange 212 can be connected to the fixed world 132 using fastening elements 214, 216, for example in the form of screws. The mounting flange 212 can be annular and completely surround the axis of symmetry 202. However, the mounting flange 212 can also be interrupted, so that it does not completely surround the axis of symmetry 202.

[0127] The shield 200A can have an opening 218 in the form of a cutout, a bore, an opening, or a recess through which a portion of the manipulator housing 140 can be led out of the interior space 204. For this purpose, the manipulator housing 140 can have the fastening web 142, which extends through the opening 218. Any number of openings 218 can be provided. Accordingly, any number of fastening webs 142 can also be provided. However, reference will be made below to only one opening 218 and one fastening web 142.

[0128] The opening 218 can be groove-shaped. The opening 218 radially penetrates the base section 210. The fastening web 142 is passed through the opening 218 without contacting the base section 210 and is connected to the fixed world 132 at the connection point 128. Since several fastening webs 142 are preferably present, several connection points 128 are also present.

[0129] The base section 210 can be closed at the front with an optional cover section 220. The cover section 220 can, for example, be connected to the base section 210 in a form-fitting and / or material-fitting manner. A form-fitting connection is created by the interlocking or engaging of at least two connection partners. For example, the cover section 220 can be screwed and / or riveted to the base section 210. In material-fitting connections, the connection partners are held together by atomic or molecular forces. Material-fitting connections are non-detachable connections that can only be separated by destroying the connecting means and / or the connection partners. Material-fitting connections can be achieved, for example, by gluing, soldering, welding, or vulcanizing.

[0130] The base section 210 and the cover section 220 can form the shield 200A as a single-piece component, in particular as a single-piece component made of a single material. "Single-piece" or "one-piece" in this case means that the shield 200A is not composed of separate subcomponents, but rather that the base section 210 and the cover section 220 together form a common component, namely the shield 200A. This means, in particular, that the base section 210 and the cover section 220 cannot be separated from each other without causing damage. In this case, the shield 200A is pot-shaped.

[0131] "Integral" means, in this case, that the shield 200A is made entirely of the same material. The shield 200A can be manufactured, for example, using a deep-drawing process or an additive or generative manufacturing process, in particular using a 3D printing process. However, the shield 200A can also be constructed in multiple parts. In this case, the base section 210 and the cover section 220 are separable from each other.

[0132] The shield 200A can have an opening 222 through which a portion of the magnet assembly 144 can be led out of the interior space 204. In the present case, the spring element 150 is passed through the opening 222. Any number of openings 222 can be provided. However, reference is made below to only one opening 222. In the present case, the opening 222 is provided centrally on the cover section 220. However, the opening 222 can also be provided on the base section 210.

[0133] Facing away from the cover section 220, the base section 210 can be closed at the front with an optional bottom section 224. The bottom section 224 can, for example, be connected to the base section 210 in a form-fitting and / or material-fitting manner. For example, the bottom section 224 can be screwed and / or riveted to the base section 210.

[0134] The base section 210 and the base section 224 can form the shield 200A as a single-piece, particularly as a single-material component. In this case, the cover section 220 is either absent or removable. In other words, at least either the cover section 220 or the base section 224 can be removed from the base section 210 in order to be able to arrange components or parts of the manipulator 134 within the shield 200A. The shield 200A can then be closed. However, both the cover section 220 and the base section 224 can also be removed from the base section 210. This can be advantageous, for example, for adjustment processes on the manipulator 134.

[0135] The shield 200A is mechanically decoupled from the manipulator 134, in particular from the manipulator housing 140. "Mechanically decoupled" in this case means that no forces can be transmitted from the manipulator 134, in particular from the manipulator housing 140, to the shield 200A or vice versa. This is achieved by the fact that the shield 200A is not rigidly connected to the manipulator housing 140, but rather that the shield 200A is directly connected to the fixed world 132 by means of the fastening flange 212. The manipulator housing 140, in particular the fastening web 142, is guided out of the interior 204 through the opening 218 without contacting the shield 200A and is separately connected to the fixed world 132 at the connection point 128.

[0136] The shield 200A can be manufactured as a welded assembly. For example, the base section 210 and the cover section 220 can be welded together. Screw connections can also be used to produce the shield 200A. The shield 200A can also be a deep-drawn component. In this case, the base section 210 and the cover section 220 can, for example, form a single-piece, in particular a single-material, component. The shield 200A can also be manufactured using subtractive manufacturing processes, such as turning, milling, and / or eroding. As previously mentioned, additive or generative manufacturing processes, in particular 3D printing processes, can also be used to manufacture the shield 200A.

[0137] The 200A shield is made of a metallic material. Materials with a high magnetic permeability (μ) are particularly used. Magnetic permeability (μ) determines the ability of materials to adapt to a magnetic field, or more precisely, the magnetization of a material in an external magnetic field. It therefore determines the permeability of a material to magnetic fields.

[0138] For the 200A shield, ferromagnetic materials with a permeability of µ rfrom 20,000 to 200,000 are used. For example, iron-nickel alloys (FeNi alloys) can be used to manufacture the 200A shield. In particular, the FeNi48 alloy can be used. To prevent corrosion, the 200A shield can be coated internally and / or externally with a corrosion-inhibiting coating. For example, a nickel-phosphorus coating (NiP coating) is used for this purpose. Annealing and / or work hardening processes that take place during the manufacture of the 200A shield are carried out in such a way that the magnetic permeability µ is not affected or that the desired permeability µ is achieved through subsequent annealing processes. r is reinstated.

[0139] The Fig. 5 shows a schematic perspective view of another embodiment of a shield 200B for the manipulator 134 as previously explained.

[0140] The shield 200B corresponds in its construction and functionality essentially to that of the shield 200A. This means that the shield 200B has a tubular base section 210, which is closed at the end by means of a cover section 220. The shield 200B can also have a base section 224 as mentioned above, but which in the Fig. 5 is not shown. The shield 200B is constructed rotationally symmetrically about a central or symmetry axis 202. Only differences between the two embodiments of the shield 200A, 200B will be discussed below.

[0141] The base section 210 has a mounting flange 212, which, however, unlike the mounting flange 212 of the shield 200A, does not completely encircle the axis of symmetry 202, but only partially. Openings 226 may be provided on the mounting flange 212, of which Fig. 5, only one is shown. Fasteners 214, 216 (not shown) as previously mentioned can be passed through the apertures 226 to attach the shield 200B to the fixed base 132.

[0142] Cuboid mounting blocks 228, 230, 232 are attached to the base section 210, to which the cover section 220 is connected. The mounting blocks 228, 230, 232 can be welded externally to the base section 210. The cover section 220 has mounting tabs 234, 236, 238 corresponding to the mounting blocks 228, 230, 232, which protrude radially beyond an outer edge 240 of the cover section 220. The mounting tabs 234, 236, 238 are perforated. This means that each fastening tab 234, 236, 238 has an opening 242, 244, 246 through which a fastening element, for example in the form of a screw, can be passed in order to connect the cover section 220 to the base section 210.

[0143] Fig. 6 shows a schematic perspective exploded view of another embodiment of a shield 200C for the manipulator 134.

[0144] In terms of its structure and functionality, the shield 200C essentially corresponds to that of the shield 200A. This means that the shield 200C has a tubular base section 210, which is closed at the end by means of a cover section 220. The shield 200C can also have a base section 224 as previously mentioned. The shield 200C is constructed rotationally symmetrically with respect to a central or symmetry axis 202. Only differences between the two embodiments of the shield 200A, 200C will be discussed below.

[0145] The base section 210 has a fastening flange 212, as previously mentioned, which completely surrounds the axis of symmetry 202 and has a plurality of openings 226, of which in the Fig. 6, only one is provided with a reference numeral. Fastening elements 214, 216 (not shown) as previously mentioned are passed through the openings 226 to connect the shield 200B to the fixed world 132.

[0146] The base section 210 has the orientation of the Fig. 6 openings 248, 250, 252, 254 arranged on the top in the form of cutouts, bores, apertures, or recesses, which radially penetrate the base section 210 relative to the axis of symmetry 202. The number of openings 248, 250, 252, 254 is arbitrary. For example, exactly four openings 248, 250, 252, 254 are provided. The openings 248, 250, 252, 254 are evenly distributed around the axis of symmetry 202. A part of the manipulator housing 140, namely in the form of the previously mentioned fastening webs 142, is led out of the interior 204 through the openings 248, 250, 252, 254 and connected to the fixed world 132. In this case, four fastening webs 142 are provided.

[0147] The cover portion 220 is not fixedly connected to the base portion 210. In particular, the cover portion 220 can be arranged within the interior space 204. For this purpose, an outer diameter of the cover portion 220 can be smaller than an inner diameter of the base portion 210. The cover portion 220 has a radial opening 256 in the form of a cutout, a bore, an aperture, or a recess through which a wiring harness of the coil assembly 148 can be passed.

[0148] Furthermore, the cover section 220 comprises a plurality of openings 258 grouped around the opening 222, of which in the Fig. 6, only one is provided with a reference symbol. The number of openings 258 is arbitrary. For example, three openings 258 can be provided, which are evenly distributed around the axis of symmetry 202. Fastening elements, for example in the form of screws, can be passed through the openings 258 to secure the cover section 220. In this case, the cover section 220 can be connected to components of the manipulator 134.

[0149] The bottom section 224 is designed to be removable from the base section 210. For this purpose, the bottom section 224 can be screwed to the base section 210. The bottom section 224 has openings 260, of which Fig. 6, only one is provided with a reference numeral. Fastening elements in the form of screws can be passed through the openings 260 in order to screw the bottom section 224 to the base section 210.

[0150] Although the present invention has been described using exemplary embodiments, it can be modified in many ways. LIST OF REFERENCE SYMBOLS 1 projection exposure system 2 Lighting system 3 Light source 4 Lighting optics 5 Object field 6 Object level 7 reticles 8 reticle holders 9 Reticle displacement drive 10 Projection optics 11 Image field 12 Image plane 13 wafers 14 wafer holders 15 Wafer relocation drive 16 Illumination radiation 17 Collector 18 Intermediate focal plane 19 Deflecting mirrors 20 first facet mirror 21 first facet 22 second facet mirror 23 second facet 100 optical system 102 optical element 102' optical element 104 Substrat 106 optically effective area 106' optically effective area 108 Front 110 Back 112 Mirror socket 114 Mirror socket 116 Mirror socket 118 Adjustment device 120 Manipulator arrangement 122 Manipulator arrangement 124 Manipulator arrangement 126 connection point 128 connection point 130 connection point 132 solid world 134 Manipulator 136 Manipulator 138 Control and regulation unit 140 Manipulator housing 142 mounting bracket 144 Magnet assembly 146 spring element 148 Coil assembly 150 spring element 152 spring element 154 dampers 156 Spring-mass-damper system 158 Arrow 160 Direction of movement 200A shield 200B shield 200C shield 202 axis of symmetry 204 Interior 206 Inside 208 Outside 210 Base Section 212 Mounting flange 214 Fastening element 216 Fastener 218 Opening 220 cover section 222 Breakthrough 224 floor section 226 Breakthrough 228 mounting block 230 mounting block 232 mounting block 234 mounting tab 236 mounting tab 238 mounting tab 240 outer edge 242 Breakthrough 244 Breakthrough 246 Breakthrough 248 Opening 250 opening 252 Opening 254 Opening 256 Opening 258 Breakthrough 260 Breakthrough IL Current situation M1 mirror M2 mirror M3 mirror M4 mirror M5 mirror M6 mirror SL target position x x-direction y y-direction z z-direction QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2008 009 600 A1 [0064, 0068] US 2006 / 0132747 A1

[0066] EP 1 614 008 B1

[0066] US 6,573,978

[0066] DE 10 2017 220 586 A1

[0071] US 2018 / 0074303 A1

[0085]

Claims

[1] Manipulator (134, 136) for adjusting an optical element (102, 102') of a projection exposure system (1), comprising a magnet assembly (144) which can be coupled to the optical element (102, 102'), a coil assembly (148) by means of which the magnet assembly (144) can be linearly displaced in order to adjust the optical element (102, 102'), and a shield (200A, 200B, 200C) for magnetically shielding the magnet assembly (144) and the coil assembly (148) from external magnetic interference fields, wherein the magnet assembly (144) and the coil assembly (148) are at least partially enclosed by the shield (200A, 200B, 200C). [2] Manipulator according to claim 1, comprising a manipulator housing (140) which is at least partially enclosed by the shield (200A, 200B, 200C), wherein the manipulator housing (140) is at least partially led out of the shield (200A, 200B, 200C). [3] Manipulator according to claim 2, wherein the manipulator housing (140) has a fastening web (142) which is led out of the shield (200A, 200B, 200C) through an opening (218, 248, 250, 252, 254) provided in the shield (200A, 200B, 200C). [4] Manipulator according to claim 2 or 3, wherein the magnet assembly (144) and the coil assembly (148) are at least partially enclosed by the manipulator housing (140). [5] Manipulator according to one of claims 2-4, wherein the shield (200A, 200B, 200C) is mechanically decoupled from the manipulator housing (140). [6] Manipulator according to one of claims 1-5, wherein the magnet assembly (144) is at least partially led out of the shield (200A, 200B, 200C) in order to adjust the optical element (102, 102'). [7] Manipulator according to one of claims 1-6, wherein the shield (200A, 200B, 200C) is constructed rotationally symmetrically to an axis of symmetry (202). [8] Manipulator according to one of claims 1-7, wherein the shield (200A, 200B, 200C) has a tubular base portion (210) which at least partially encloses the magnet assembly (144) and the coil assembly (148). [9] Manipulator according to claim 8, wherein the base portion (210) has a mounting flange (212) for attaching the shield (200A, 200B, 200C) to a fixed world (132). [10] Manipulator according to claim 8 or 9, wherein the shield (200A, 200B, 200C) has a cover portion (220) and / or a bottom portion (224) for closing the base portion (210) at the front. [11] Manipulator according to one of claims 1-10, wherein the shield (200A, 200B, 200C) is made of a metallic material, in particular of an iron-nickel alloy, with a magnetic permeability µ r from 20,000 to 200,000 are manufactured. [12] Manipulator according to one of claims 1-11, wherein the shield (200A, 200B, 200C) is coated with an anti-corrosive coating, in particular with a nickel-phosphorus coating. [13] Optical system (100) for a projection exposure apparatus (1), comprising an optical element (102, 102'), and a manipulator (134, 136) according to one of claims 1-12, wherein the magnet assembly (144) is coupled to the optical element (102, 102'). [14] Optical system according to claim 13, comprising a fixed world (132), wherein the manipulator (134, 136) has a manipulator housing (140) which is at least partially enclosed by the shield (200A, 200B, 200C), wherein the manipulator housing (140) is connected to the fixed world (132), and wherein the shield (200A, 200B, 200C) is connected to the fixed world (132). [15] Projection exposure system (1) with a manipulator (134, 136) according to one of claims 1-12 and / or an optical system (100) according to claim 13 or 14.

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