METHOD AND COATING SYSTEM FOR MANUFACTURING A MIRROR ASSEMBLY - Patent application

Abstract

The present invention relates to a method for manufacturing a mirror assembly, a mirror assembly, and a coating system. The mirror assembly may in particular be a mirror assembly for microlithography, for example for a microlithography projection exposure apparatus. In the method according to the invention, a coating process for a plurality of mirror substrates 106, 206, 306, 406 is carried out in a coating system 100, in which at least one target 103, 203, 303, 403, 503 supplies coating material for depositing at least one respective layer system on each of the mirror substrates 106, 206, 306, 406, and tilts the mirror substrates 106, 206, 306, 406 at a tilt angle that can be set individually for each mirror substrate 106, 206, 306, 406 in order to individually adjust the thickness profile formed in the coating process.

Description

[Technical Field]

[0001] This application claims priority from German Patent Application No. 10 2023 200 603.0, filed on January 26, 2023, the content of which is incorporated herein by reference.

[0002] The present invention relates to a method and a coating system for manufacturing a mirror assembly, in particular the mirror assembly may be a microlithography mirror assembly for example for a microlithography projection exposure apparatus. [Background technology]

[0003] Microlithography is used to manufacture finely structured components, such as integrated circuits or LCDs. The microlithography process is carried out in so-called projection exposure apparatuses, which comprise an illumination device and a projection lens. In this case, the image of a mask (reticle), illuminated by the illumination device, is projected by the projection lens onto a substrate (e.g., a silicon wafer) that is covered with a photosensitive layer (photoresist) and placed in the image plane of the projection lens, so as to transfer the mask structure into the photosensitive coating of the substrate.

[0004] For example, projection lenses designed for the EUV range at wavelengths of about 13 nm or about 7 nm use mirrors as optical components for the imaging process due to the unavailability of suitable light-transmitting and refractive materials.

[0005] The use of mirror assemblies consisting of a number of individual mirrors (e.g. in the form of facet mirrors or pupil facet mirrors) for flexibly setting different illumination angle distributions is known not only in illumination devices of microlithography projection exposure apparatus designed for EUV operation, but also in microlithography projection exposure apparatus designed for operation at wavelengths in the DUV range (e.g. at wavelengths of about 248 nm or about 193 nm). These individual mirrors can each be designed to be settable or tiltable independently of one another by means of flexures and can be configured as blocks of individual micromirrors in the form of microelectromechanical systems (so-called "MEMS mirrors").

[0006] For example, magnetron coating systems are used in mirror production. Such magnetron coating systems usually comprise several magnetrons, each of which is assigned a target with a corresponding coating material. To coat a substrate, each substrate (which is understood to mean the substrate on which a layer or layer system is applied in a coating process) is guided through a coating position opposite each target or magnetron.

[0007] Practical problems that arise include coating errors, particularly in the form of coating thickness errors or due to alignment errors of the respective coating mounts, which are generally unavoidable in practical coating processes, as well as undesirable drifts (i.e., temporal variations in the layer thicknesses set in the coating process, both within the layer structure and across multiple mirrors produced in succession). These problems are particularly acute in the case of EUV mirrors with periodic multilayer systems, since the systematic propagation of the respective layer thickness errors in the layer thickness profile leads to a significant deterioration in the overall performance of the optical system, even if the individual layers already deviate slightly from their target layer thicknesses.

[0008] In addition to the need to correct for the above effects, there is also a real need for flexible and precise selection of layer properties to improve reflectivity and ultimately the overall performance of the optical system.

[0009] With respect to the prior art, see, by way of example only, US Pat. Nos. 5,629,999, 5,729,949, 5,729,959, 5,739,963, 5,749,975, 5,759,985, 5,769,097, 5,779,063, and 5,829,097. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] DE 10 2016 201 564 A1 [Patent Document 2] DE 10 2015 225 535 A1 [Patent Document 3] DE 10 2015 217 603 [Patent Document 4] DE 10 2015 217 603 [Patent Document 5] DE 10 2012 215 359 A1 [Patent Document 6] DE 10 2012 204 833 A1 [Patent Document 7] International Publication No. 2022 / 008102 Brochure [Patent Document 8] U.S. Patent No. 10,423,073 Summary of the Invention [Problem to be solved by the invention]

[0011] In view of the above, it is an object of the present invention to provide a method and a coating system for manufacturing a mirror assembly that allows flexible manipulation of layer properties, e.g., for the correction of layer thickness errors and / or alignment errors. [Means for solving the problem]

[0012] This problem is solved by the features of the independent patent claims.

[0013] A method for manufacturing a mirror assembly having a plurality of mirror elements, in particular for microlithography, according to the present invention comprises supplying a coating material from at least one target to a plurality of mirror substrates in a coating process carried out in a coating system, for the purpose of depositing a respective layer system on each of the mirror substrates.

[0014] The method is characterized in that the mirror substrates are each tilted by a tilt angle that can be set individually for each mirror substrate in order to set individually the respective thickness profile formed in the coating process. This tilting of the mirror substrates in the coating process or coating system can in particular be performed "in situ".

[0015] In this regard, a thickness profile within the meaning of the present application is understood to be the transverse thickness profile of a layer or layer system. In principle, the thickness profile can be a constant thickness profile or a thickness profile that varies across the optically active surface of the mirror element. In particular, the layer system can also include a reflective layer system and possibly further functional layers.

[0016] In this regard, within the meaning of the present application, the expression "each tilting the mirror elements at a tilt angle that can be set individually for each mirror substrate" is understood to mean both an embodiment in which several or all mirror elements are each tilted at the same tilt angle and an embodiment in which several or all mirror elements are tilted at mutually different tilt angles. Furthermore, the tilt angle set for each individual mirror element may vary over time or may remain constant over time depending on the embodiment. Furthermore, the tilt angle set for each one or more mirror elements may have a value that is not equal to zero or may have a value of zero.

[0017] The starting point of the present invention is the concept that changing the deposition angle or evaporation angle in a coating process can affect the layer thickness profile and can also affect further layer properties (e.g., roughness, crystallinity, layer stress, etc.). In this regard, the present invention particularly includes the principle of controlled modification of these properties by tilting the respective mirror substrate. If a degradation of certain parameters or layer properties may occur, further adaptations to the process conditions (known per se) can be made to counteract this. For example, if a relatively large tilt causes an undesirable increase in roughness in a particular system, this can be influenced or reduced, for example, by optimizing the operating pressure.

[0018] In particular, within the scope of the manufacture of mirror assemblies having several mirrors, the invention is based on the idea that, by active control of the individual mirror substrates in the coating process, an individual setting of the respective tilt angle for each mirror substrate is carried out before or during the deposition of each layer system on the individual mirror substrate, so that the resulting change in the deposition angle (and thus in the amount of coating material deposited on the mirror substrate) influences in particular the respective thickness profile and possibly also further layer properties. As a result of the individual setting of the respective tilt angle for each mirror substrate, an individual thickness factor for the coating process can be assigned to each mirror substrate to be coated or each produced mirror element.

[0019] In this case, the slope of each individual mirror substrate can be dynamically changed in the coating process, and it is particularly possible to form thickness profiles in which there are variations in layer thickness or possibly further layer properties within one and the same mirror element (and not just at the boundaries of adjacent mirror elements). In other words, it is particularly possible according to the invention to produce mirror assemblies in which the boundaries between regions of different layer properties do not correspond to the boundaries between adjacent mirror elements.

[0020] By flexibly and independently tilting the individual mirror substrates as described above, the present invention is particularly different from conventional approaches, which simply statically set a specific tilt angle for each group of blocks of mirror substrates before loading them into a process chamber, then perform a coating process after loading each block into the process chamber, and finally assemble the corresponding blocks to form a mirror assembly.

[0021] According to the invention, the individual tilting of the mirror substrates, on the one hand, changes the deposition angle to be set (and thus the average thickness coefficient during the coating compared to each adjacent mirror substrate), and, on the other hand, also changes the layer thickness profile itself that is formed over the respective mirror substrate in the coating process, so that particular flexibility is also provided with regard to the configuration of the mirror assembly. Depending on the respective concrete application scenario, the last-mentioned effect (i.e. a locally varying layer thickness profile) may then be desirable or may even be used to correct undesired effects or aberrations in the respective optical system.

[0022] According to one embodiment, tilting is performed such that systematic coating errors of the coating system are at least partially compensated for by the thickness profile formed for the multiple mirror substrates.

[0023] According to one embodiment, tilting is performed such that alignment errors of multiple mirror substrates of a coating system are at least partially compensated for by the thickness profile formed for the mirror substrates.

[0024] According to one embodiment, different thickness profiles are formed for multiple mirror substrates.

[0025] According to one embodiment, the tilting is performed such that a respective constant thickness profile is formed for each individual mirror substrate.

[0026] According to one embodiment, modifying the average deposition angle in the coating process modifies at least one further layer property in addition to the layer thickness profile, in particular the roughness, the crystallinity or the layer stress.

[0027] According to one embodiment, the mirror substrate is moved along a predetermined trajectory relative to the target during the coating process.

[0028] According to one embodiment, the tilt of each mirror substrate is changed during each pass of the trajectory.

[0029] According to one embodiment, this modification is performed such that each mirror substrate is tilted either towards the target over the entire path of the trajectory, or away from the target over the entire path of the trajectory.

[0030] According to one embodiment, the mirror substrate is rotated during the coating process and tilting is performed based on the rotation angle of this rotation.

[0031] According to one embodiment, the tilting is performed such that gaps located between adjacent mirror substrates are at least partially shielded in the coating process as a result of the tilting.

[0032] According to one embodiment, the supply of coating material by at least one target is performed at a time-varying rate, and in particular in scenarios where the rotational position of the coating mount does not shield a gap located between adjacent mirror substrates, the supply rate of the coating material ("sputter rate") can be reduced to avoid contamination of machine components located behind the gap with the coating material.

[0033] In embodiments, the trajectory of the coating mount may be designed so that the mirror substrate is not positioned perpendicularly above the target at any point during the coating process.

[0034] Furthermore, in embodiments, the rotational movement may possibly be performed only around a single (spin) axis of rotation.

[0035] Furthermore, in embodiments of the present invention, the effect of tilting the mirror substrate according to the present invention can be amplified in the coating process by utilizing the radial dependence of the deposited layer thickness. In this regard, it is possible to take advantage of the fact that the amount of deposited coating material also varies depending on the position of the mirror substrate on the coating mount. At a relatively large mounting radius (i.e., at a position further outward in the radial direction on the coating mount), the substrate passes the edge of the material source, where the layer-forming particle distribution is non-uniform. At this position, there is relatively more coating material from the target center than from the edge of the target. Tilting the substrate toward the target center favors angles of incidence with a strong particle flux, while disfavoring angles of incidence with a weak particle flux (and vice versa). Consequently, this also increases the angular dependence of the layer thickness obtained in the coating process, i.e., the "layer thickness gain" achieved by the coating process according to the present invention, by several percent relative to the layer thickness.

[0036] According to one embodiment, the mirror assembly is designed for an operating wavelength below 30 nm, in particular below 15 nm.

[0037] The invention also relates to a mirror assembly, particularly a microlithography mirror assembly, manufactured using a method having the above-described features.

[0038] The present invention provides a coating system for manufacturing mirror assemblies, particularly microlithography mirror assemblies, having a process chamber, the process chamber including: at least one target for supplying coating material; a coating mount for holding a plurality of mirror substrates; a first drive unit for effecting translational movement of the coating mount; a second drive unit for effecting a rotational movement of the coating mount; a third drive unit that allows the tilt of the mirror substrate to be individually set during the coating process; The present invention also relates to a coating system in which the

[0039] The invention further relates to a microlithography projection exposure apparatus comprising an illumination device and a projection lens, which illumination device illuminates a mask located in the object plane of the projection lens during operation of the projection exposure apparatus, and which projection lens images structures on said mask onto a photosensitive layer located in the image plane of the projection lens, and which comprises at least one mirror assembly manufactured using a method having the above-described characteristics.

[0040] Further configurations of the invention will become apparent from the description and the dependent claims.

[0041] The invention will be explained in more detail below on the basis of exemplary embodiments shown in the accompanying drawings. [Brief explanation of the drawings]

[0042] [Figure 1] 1 shows a schematic diagram of a possible construction in principle of a coating system according to the invention; [Figure 2] 1 shows a schematic diagram illustrating an exemplary embodiment of the method according to the invention; [Figure 3] 1 shows a schematic diagram illustrating an exemplary embodiment of the method according to the invention; [Figure 4] 1 shows a schematic diagram illustrating an exemplary embodiment of the method according to the invention; [Figure 5] 1 shows a schematic diagram illustrating an exemplary embodiment of the method according to the invention; [Figure 6] A schematic diagram of a projection exposure tool designed to operate with EUV is shown. DETAILED DESCRIPTION OF THE INVENTION

[0043] FIG. 1 first shows a schematic diagram of a possible configuration of a coating system 100 according to the invention. Here, a coating mount 102 holding multiple mirror substrates 106 and at least one target 103 for supplying coating material are arranged in a process chamber 101 (connected to a vacuum pump, not shown here). As shown in FIG. 1 (without limiting the invention), multiple mirror substrates 106 or finally produced mirror elements can be divided into individual blocks 150. To deposit each layer system on each mirror substrate, the coating mount 102 carrying the mirror substrate 106 is guided over the at least one target 103 along a predetermined trajectory. In doing so, the coating mount 102 performs a translational movement effected by a first drive unit 108 and, optionally, a rotational movement effected by a second drive unit 109. In addition to the first and second drive units, the coating system 100 according to the invention also comprises a third drive unit 110, which allows the tilt of the mirror substrate 106 to be individually set during the coating process. Mechanical components or joints assigned to the mirror substrate 106 are designated "107".

[0044] In the following, it is assumed that in order to manufacture a mirror assembly (which may be designed for operation in the EUV or DUV wavelength range), each desired thickness profile of the layer structure (reflective layer system and possibly functional layers) formed on each mirror substrate should be formed for each individual mirror element of the mirror assembly.

[0045] Exemplary embodiments of the method according to the invention will now be described using a schematic representation with reference to the schematic diagrams of Figures 2a) to 5b). These embodiments have in common the tilting of each mirror substrate at an individually settable tilt angle (or independently of each other) for individual setting of each thickness profile formed in a coating process (for example carried out in the coating system of Figure 1). In this case, the power supply required for tilting can be provided on the coating mount side, or alternatively, a storage battery can be used.

[0046] 2a-c) each illustrate a predetermined trajectory of the mirror substrate 206 relative to the target 203, with "204" indicating coating material being applied to the mirror substrate 206 by the target 203. By way of example only (and not limitation), the dimensions of an individual mirror substrate 206 may be 1 mm by 1 mm. In this regard, FIG. 2a) illustrates the trajectory of the mirror substrate 206 in an untilted state, while FIG. 2b) illustrates the trajectory in a tilted state with a constant tilt angle over time. FIG. 2c) also illustrates the tilted trajectory, but unlike FIG. 2b, the tilt of the mirror substrate 206 is changed during each pass of the trajectory shown in FIG. 2c). In particular, this single change in the tilt angle of the mirror substrate 206 may be performed upon reaching a position directly above the target 203 and may be performed to tilt the mirror substrate 206, on average, toward the target 203. In yet another embodiment, the tilt angle may be changed to tilt the mirror substrate 206, on average, away from the target 203. In each of the two scenarios, it is possible to avoid the symmetry breaking that typically occurs during movement of the mirror substrate 206 relative to the target, and therefore to achieve a constant thickness profile during coating of the corresponding mirror substrate 206.

[0047] Quantitatively, starting from a perpendicular coating, cos(0.1)≈0.995, so a 100 mrad (equivalent to approximately 6°) change in deposition angle due to tilting according to the present invention results in a change in layer thickness of approximately 0.5%. Due to the nonlinear cosine function, the effect of a change in deposition angle on layer thickness increases significantly at larger deposition angles. A 10° change in the mean incidence angle of the layer-forming particles results in a change in layer thickness of approximately 2.2%, while a 30° change in the mean incidence angle results in a change in layer thickness of approximately 6.2%.

[0048] In yet another embodiment, even in the case of tilting the mirror substrate according to the invention, it is possible to consider rotating the mirror during the coating process, with the tilting being particularly performed according to the respective rotation angle of this rotation. The schematic diagrams in Figures 3a) and 3b) show said rotational movement in a plan view. The dynamic tilting of the mirror substrate 306 allows the mirror substrate 306 to always (i.e., particularly throughout the entire rotational movement) be aligned towards the target 303 (or possibly also be directed away from the target 303, for example, if a thinner coating is desired). In this regard, the control of the tilting of the mirror substrate must be performed at a higher speed than the rotational speed of the rotational movement of the coating mount 302 carrying the mirror substrate 306.

[0049] In yet another embodiment, tilting of the mirror substrates according to the present invention can also be performed in such a way that the gaps or intervals located between adjacent mirror substrates are at least partially shielded, i.e., hidden by the coating, as a result of the tilting. This is shown in the schematic diagrams of Figures 4a) and 4b). According to Figure 4a), the coating material can pass through the gap between adjacent mirror substrates 406 and reach and potentially contaminate the mechanical component 407 located behind the mirror substrate, whereas according to Figure 4b), the mechanical component 407 is protected as a result of the appropriate tilting and the resulting shielding.

[0050] If necessary, an aperture can be additionally used to narrow the deposition angle distribution, and / or the coating material supply rate ("sputter rate") of at least one target can be varied over time so as to reduce the amount of coating material reaching each mirror substrate from the target during unfavorable deposition angle phases (within the sense of the contamination potential). Figures 5a) and 5b) show schematic diagrams (again in plan view of the coating mount 502 with the mirror substrates 506 and the target 503) of scenarios where the above-mentioned shielding of the gap between adjacent mirror substrates 506 is achieved (Figure 5a) or not (Figure 5b), depending on the rotational position of the coating mount 502. In this case, the coating material supply rate ("sputter rate") of at least one target is reduced in the rotational position of the coating mount 502 shown in Figure 5b (where the gap 506a between the mirror substrates 506 is not shielded) in order to avoid contamination of the machine components located behind the gap with the coating material.

[0051] In yet another embodiment, the trajectory of the coating mount can also be designed such that at no point during the coating process the mirror substrate is positioned vertically above the target, and in particular the rotational movement is possibly only performed around a single (spin) rotation axis.

[0052] FIG. 6 shows a schematic representation in meridian section of a possible structure of a microlithographic projection exposure apparatus designed to operate with EUV.

[0053] According to Fig. 6, the projection exposure apparatus 1 comprises an illumination device 2 and a projection lens 10. In addition to a light source or radiation source 3, an illumination optical unit 4 for illuminating an object field 5 in an object plane 6 is also provided. In an alternative embodiment, the light source 3 can also be provided as a module separate from the rest of the illumination device. In this case, the illumination device does not include the light source 3.

[0054] Here, 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 the scanning direction, by a reticle displacement drive 9. For illustrative purposes, a Cartesian xyz coordinate system is shown in FIG. 6. The x direction runs perpendicular to the plane of the drawing. The y direction runs horizontally and the z direction runs vertically. In FIG. 6, the scanning direction runs along the y direction. The z direction runs perpendicular to the object plane 6.

[0055] The projection lens 10 serves to image the object field 5 into an image field 11 in an image plane 12. Structures on the reticle 7 are imaged onto a photosensitive layer of a wafer 13 that is 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 is displaceable, in particular in the y-direction, by means of a wafer displacement drive 15. The displacement of the reticle 7, firstly by the reticle displacement drive 9, and the displacement of the wafer 13, secondly by the wafer displacement drive 15, can be synchronized with one another.

[0056] The radiation source 3 is an EUV radiation source. The radiation source 3 particularly emits EUV radiation, hereinafter also referred to as working radiation or illumination radiation. In particular, the working radiation has a wavelength in the range of 5 nm to 30 nm. The radiation source 3 can, for example, be a plasma source, a synchrotron-based radiation source, or a free electron laser (FEL). The illumination radiation 16 leaving the radiation source 3 is focused by a collector 17 and propagates through an intermediate focus in an intermediate focal plane 18 to the illumination optical unit 4. The illumination optical unit 4 comprises a deflection mirror 19 and, arranged downstream thereof in the beam path, a first facet mirror 20 (with the diagrammatically indicated facet 21) and a second facet mirror 22 (with the diagrammatically indicated facet 23). The facet mirrors 21, 22 can, for example, be manufactured using the method according to the invention or using the coating system according to the invention.

[0057] The projection lens 10 comprises a number of mirrors Mi (i=1, 2, ...), which are numbered according to their arrangement in the beam path of the projection exposure apparatus 1. In the example shown in Figure 6, the projection lens 10 comprises six mirrors M1 to M6. 4, 8, 10, 12 or any other number of mirrors Mi are equally possible. The penultimate mirror M5 and the final mirror M6 each have a passage aperture for the illumination radiation 16. The projection lens 10 is a double-shielded optical unit. The projection lens 10 has an image-side numerical aperture which is greater than 0.5, may be greater than 0.6, and may be, for example, 0.7 or 0.75.

[0058] While the present invention has been described with reference to specific embodiments, numerous variations and alternative embodiments will be apparent to those skilled in the art, for example, by combining and / or substituting features of the particular embodiments. Accordingly, it will be understood by those skilled in the art that such variations and alternative embodiments are encompassed by the present invention, and that the scope of the present invention is limited only in the sense of the appended claims and equivalents thereof.

Claims

1. 1. A method for manufacturing a mirror assembly having a plurality of mirror elements, particularly for microlithography, comprising the steps of: a coating process carried out in the coating system (100) supplying a coating material from at least one target (103, 203, 303, 403, 503) to a plurality of mirror substrates (106, 206, 306, 406) for the purpose of depositing a respective layer system on each of said mirror substrates; and A method for tilting each of said mirror substrates (106, 206, 306, 406) at a tilt angle that can be set individually for each of said mirror substrates in order to set individually each thickness profile formed in a coating process.

2. 2. The method of claim 1, wherein tilting is performed such that systematic coating errors of the coating system (100) are at least partially compensated for by a thickness profile formed for the plurality of mirror substrates (106, 206, 306, 406).

3. 3. The method according to claim 1 or 2, characterized in that tilting is performed so that alignment errors of the plurality of mirror substrates (106, 206, 306, 406) of the coating system (100) are at least partially compensated for by a thickness profile formed on the mirror substrates.

4. The method according to any one of claims 1 to 3, characterized in that the tilting is performed so that different thickness profiles are formed for the mirror substrates (106, 206, 306, 406).

5. The method according to any one of claims 1 to 4, characterized in that the tilting is performed in such a way that a respectively constant thickness profile is formed for each of the mirror substrates (106, 206, 306, 406).

6. 6. The method according to claim 1, wherein the coating process changes the average deposition angle to change at least one further layer property, in addition to the layer thickness profile, in particular the roughness, the crystallinity or the layer stress.

7. The method according to any one of the preceding claims, characterized in that the mirror substrate (106, 206, 306, 406) is moved along a predetermined trajectory relative to the target (103, 203, 303, 403, 503) during the coating process.

8. 8. The method of claim 7, wherein the tilt of each of the mirror substrates (106, 206, 306, 406) is changed during each pass of the trajectory.

9. 9. The method of claim 8, wherein the modification is performed such that each of the mirror substrates (106, 206, 306, 40) is tilted toward the target (103, 203, 303, 403, 503) over the entire path of the trajectory or tilted away from the target (103, 203, 303, 403, 503) over the entire path of the trajectory.

10. The method according to any one of claims 1 to 9, characterized in that the mirror substrate (106, 206, 306, 406) is rotated during the coating process and tilting is performed depending on the rotation angle of said rotation.

11. 11. The method according to any one of claims 1 to 10, characterized in that the tilting is performed in such a way that gaps located between adjacent mirror substrates (106, 206, 306, 406) are at least partially shielded in the coating process as a result of the tilting.

12. The method according to any one of the preceding claims, characterized in that the supply of coating material by said at least one target (103, 203, 303, 403, 503) is performed at a time-varying rate.

13. The method according to any one of the preceding claims, characterized in that the mirror assembly is designed for an operating wavelength of less than 30 nm, in particular less than 15 nm.

14. A mirror assembly, in particular a microlithography mirror assembly, characterized in that it is manufactured using a method according to any one of claims 1 to 13.

15. A coating system for manufacturing mirror assemblies, in particular microlithography mirror assemblies, having a process chamber (101), comprising: at least one target (103, 203, 303, 403, 503) for supplying a coating material; a coating mount (102) for holding a plurality of mirror substrates (106, 206, 306, 406); a first drive unit (108) for effecting a translational movement of the coating mount (102); a second drive unit (109) for effecting a rotational movement of the coating mount (102); a third drive unit (110) that allows the tilt of the mirror substrate (106, 206, 306, 406) to be individually set during the coating process; The coating system is placed.

16. 14. A microlithography projection exposure apparatus comprising an illumination device and a projection lens, wherein the illumination device illuminates a mask located in an object plane of the projection lens during operation of the projection exposure apparatus, and the projection lens images structures on the mask onto a photosensitive layer located in an image plane of the projection lens, the projection exposure apparatus comprising at least one mirror assembly manufactured using a method according to any one of claims 1 to 13.

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