Supporting optical components

Abstract

The invention relates to an arrangement of a microlithography imaging device, in particular for use with light in the extreme ultraviolet (EUV) range, comprising a holding device (110) for holding an optical element (109), wherein the optical element (109) comprises an optical surface (109.1) and defines a main extension plane, wherein the optical element (109) defines a radial direction and a circumferential direction. The holding device (110) comprises a base unit (110.1) and three or more separate holding units (110.2), wherein the base unit (110.1) comprises a plurality of support interface units (110.3) which are spaced apart from each other in the circumferential direction and are used to connect the holding device (110) to a support structure (102.1). The holding units (110.2) are connected to the base unit (110.1) and are arranged in a manner distributed along the circumferential direction and spaced apart from each other. The holding unit (110.2) is configured to hold the optical element (109) relative to the base unit (110.1). The base unit comprises at least one supporting film element (110.4), wherein the at least one supporting film element (110.4) extends mainly along the circumferential direction and along the radial direction, wherein the at least one supporting film element (110.4) has a thickness dimension transverse to the circumferential direction and the radial direction. The holding unit (110.2) is arranged on the front side of the at least one supporting film element (110.4) facing the optical element (109).

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority under 35 U.S.C. §119 to German Patent Application No. 102019 112224.4, filed on May 10, 2019, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The invention relates to an optical arrangement for microlithography suitable for use with UV imaging light, in particular light in the extreme ultraviolet (EUV) range. Furthermore, the invention relates to an optical imaging device comprising such an arrangement. The invention can be used in conjunction with any desired optical imaging method. In particular, it can be advantageously used in the production or testing of microelectronic circuits and optical components for this purpose (e.g. optical masks). Background Art

[0004] Optical devices used in conjunction with the production of microelectronic circuits usually comprise a plurality of optical element units, which comprise one or more optical elements, such as lens elements, mirrors, or gratings, arranged in the imaging beam path. The aforementioned optical elements usually cooperate in an imaging process in order to transfer an image of an object, such as a pattern formed on a mask, onto a substrate, such as a so-called wafer. The optical elements are usually combined in one or more functional groups which are, if appropriate, held in separate imaging units. In particular in the case of predominantly refractive systems operating at wavelengths in the so-called vacuum ultraviolet (VUV) range, such as at a wavelength of 193 nm, such imaging units are often formed by a stack of optical modules holding one or more optical elements. The aforementioned optical modules usually comprise a support structure having a substantially annular outer support unit which supports one or more optical element holders, which in turn hold the respective optical elements.

[0005] The ever-increasing miniaturization of semiconductor components has led to a demand for continuously improving the resolution of optical systems used in their production. This demand for improved resolution requires increasing the numerical aperture (NA) and imaging accuracy of the optical system.

[0006] One approach for obtaining an improved optical resolution is to reduce the wavelength of the light used in the imaging process. The trend in recent years has gradually promoted the development of systems in which light in the so-called extreme ultraviolet (EUV) range (usually at a wavelength of 5 nm to 20 nm, mostly at a wavelength of approximately 13 nm) is used. In this EUV range, it is no longer possible to use conventional refractive optical systems. This is due to the fact that in this EUV range, the materials used for refractive optical systems have an absorption that is too high to achieve acceptable imaging results with the available optical power. Therefore, in this EUV range, it is necessary to use reflective optical systems for imaging.

[0007] This transition to purely reflective optical systems with high numerical aperture (eg NA>0.4 to 0.5) in the UV range leads to considerable challenges regarding the design of the imaging device.

[0008] The above mentioned factors lead to very strict requirements regarding the position and / or orientation of the optical elements involved in the imaging relative to each other, as well as regarding the deformation of the individual optical elements in order to achieve the required imaging accuracy. Moreover, it is necessary to maintain this high imaging accuracy throughout its operation and ultimately throughout the service life of the system.

[0009] Therefore, the components of the optical imaging device that cooperate during the imaging process (i.e., for example, the optical elements of the illumination device, the mask, the optical elements of the projection device, and the substrate) must be supported in a well-defined manner to maintain a predetermined well-defined spatial relationship between these components and to obtain minimal undesired deformation of these components in order to ultimately achieve the highest possible imaging quality.

[0010] In this context, a system-essential problem that arises, in particular in the aforementioned EUV systems, is that at least some of the illumination device and the projection device as well as the optical elements are relatively large and heavy optical units. However, in order to meet the requirements in terms of accuracy, these heavy units should be exchangeable and correspondingly adjustable and, due to their mounting design, should not already experience unnecessary or inaccurately defined deformations. For these reasons, for the purpose of supporting these optical units or elements, as is known, for example, from US Pat. No. 7,760,327 B2 (Scherle et al., the entire disclosure of which is hereby incorporated by reference), a so-called three-point support is used, which is usually realized by three detachable holding units evenly distributed along the circumference (the aforementioned holding units are usually designed in the form of so-called hexapod kinematics).

[0011] This three-point support allows a statically defined mounting to be obtained or to avoid a statically overdefined mounting, thereby avoiding unnecessary parasitic stresses and deformations in the optical unit (as may occur due to production inaccuracies or deformations of the support structure).

[0012] The disadvantage of this statically determined three-point support is that, for example, in the case of impact loads (as may occur during transport of the imaging device), the main load must be carried by a single one of the three holding units in the most unfavorable load case, i.e. if the load is in a specific load direction, the two other holding units are substantially compliant in this load direction and therefore cannot carry any load. The holding units must therefore be of a relatively strong and complex design in order to ensure a reliable support of the optical element. Therefore, in particular the detachable connection to the optical element has a complex design in order to avoid or reduce the introduction of parasitic stresses (and the resulting parasitic deformations) where possible.

[0013] US 8,441,747 B2 (Heintel et al., the entire disclosure of which is incorporated herein by reference) discloses holding an optical element at its outer circumference by means of a plurality of holding units which are adhesively bonded to the outer circumference of the optical element and arranged on a support ring. This does achieve a better distribution of the operating loads due to the adhesive bonding, as well as a compact configuration. However, the problem that arises is that the adhesive bonding at the beginning does not facilitate a simple replacement of the optical element. Moreover, in the event of an impact on the arrangement, depending on the direction of the impact (or the acceleration acting on the component), there are very different impact loads at the individual holding units. In this specification, the ratio of the maximum impact load to the minimum impact load may be as high as 20. Therefore, in this case, the impact load on the individual holding units is not evenly distributed either; instead, a large part of the impact load has to be absorbed by several individual holding devices. Furthermore, the problem that naturally arises due to this static over-determined support is that parasitic stresses are introduced into the optical element in the event of deformations of the support ring. Summary of the invention

[0014] The present invention is therefore based on the object of providing a microlithography optical arrangement, as well as a corresponding optical imaging device comprising such an arrangement, and a method for supporting an optical element, which do not have the aforementioned disadvantages or at least have them to a lesser extent and, in particular, make it easy to obtain a support for an optical element which has small dimensions and is at the same time as strong as possible in terms of resistance to impact loads.

[0015] The invention achieves this object with the features of the independent claims.

[0016] The invention is based at least in part on the following technical teaching: A support of an optical element that is strong against impact loads but has small dimensions can be easily obtained if a plurality of holding units, preferably more than three holding units, each separately holding an optical element, are provided, wherein the holding units are arranged on at least one supporting film element of a base unit, the aforementioned supporting film element preferably extending in a circumferential direction and in a radial direction. Among the plurality of holding units, preferably more than three holding units, a reduction in the maximum load acting on a single holding unit even in an undesired situation (e.g., in a worst-case situation that is usually defined by the manufacturer and / or user of the system for design purposes) can be achieved first, at least in part, due to the division of loads, in particular impact loads, occurring at the optical element during production, transportation, and operation of the imaging device among the plurality of holding units, preferably more than three holding units.

[0017] Due to the arrangement of the respective holding unit on the supporting film element, it is also possible, by the design of the supporting film element and / or by the way in which the supporting film element is connected to the supporting interface unit, to set the stiffness of the holding device between the optical element side attack point of the forces of the respective holding unit and the support structure side attack point of the forces at the respective supporting interface unit. It can therefore be advantageously achieved that this stiffness is at least relatively substantially balanced, preferably to the greatest possible extent, for a plurality of holding units, preferably all holding units, in particular in certain respective degrees of freedom. The greater this balance in a particular degree of freedom (thus, the smaller the differences in stiffness between the individual holding units in this degree of freedom, or the narrower the distribution of this stiffness among the holding units), the more evenly the impact load is divided among the holding units in the respective degree of freedom. In the desired case, possibly in the ideal case, it is even possible that all holding units will obtain at least substantially the same stiffness with respect to the support structure side attack point of the forces in the respective degree of freedom. In this case, the impact load in the respective degree of freedom is then distributed substantially evenly among all holding units.

[0018] Thus, at the holding unit, the risk that the expected impact load exceeds the holding force of the holding unit in the most unfavorable case (usually defined for design purposes by the manufacturer and / or user of the system) can be reliably reduced without having to provide a large safety factor and therefore without having to increase the size of the holding unit. Therefore, in some embodiments, despite the simplification of the holding unit, the impact safety or reliability against system failure under impact loads can still be advantageously improved. Thus, the holding unit can have a simpler and therefore more space-saving design, which in turn helps to further increase the number of holding units. Ultimately, in some embodiments, this may allow an advantageously large number of holding units to be achieved, wherein the impact load is evenly distributed among the holding units.

[0019] A further advantage of the supporting film element, at least in some embodiments, is the fact that, in addition to the increased stability against impacts, the achievable imaging quality is also improved, since the optical element is advantageously supported uniformly at many points, so that it is possible to substantially reduce the fluctuations of the optical element due to its weight. Furthermore, an advantageously low stiffness of the holding device relative to the optical element can be achieved by using a supporting film element.

[0020] A further advantage of the supporting film element, at least in some embodiments, is the fact that it can decouple the holding units from one another with respect to the degree of freedom of tilting, whose tilting axis is located in the supporting film element. This is due in particular to the fact that the supporting film element can be deformed relatively easily, in particular by denting. Advantageously, at least in some embodiments, this can result in a reduction of parasitic stresses introduced into the optical element during deformation of the holding device.

[0021] According to a first aspect, the present invention therefore relates to an arrangement of a microlithography imaging device, in particular for use with light in the extreme ultraviolet (EUV) range, comprising a holding device for holding an optical element. The optical element comprises an optical surface and defines a main extension plane, wherein the optical element defines a radial direction and a circumferential direction. The holding device comprises a base unit and a plurality of separate holding units, in particular more than three separate holding units, wherein the base unit for connecting the holding device to a support structure comprises a plurality of support interface units, which are spaced apart from each other in the circumferential direction. The holding units are connected to the base unit and are arranged in a manner distributed along the circumferential direction and spaced apart from each other. In addition, the holding units are configured to hold the optical element relative to the base unit. The base unit comprises at least one supporting film element, wherein the at least one supporting film element extends mainly along the circumferential direction and along the radial direction, wherein the at least one supporting film element has a thickness dimension transverse to the circumferential direction and the radial direction. In the present specification, the holding unit is arranged on the front side of the at least one supporting film element facing the optical element.

[0022] In principle, the supporting film element can have any suitable design and configuration for achieving the above-described functions of decoupling and equalizing the stiffnesses among the individual holding units. For example, any winding and / or bending configuration of the film element can be realized (in a cross-sectional plane extending perpendicularly to the circumferential direction) in order to set the stiffness or compliance in a targeted manner in (one or more) specific degrees of freedom. Thus, the cross-sectional profile of the film element can have an at least partially straight and / or at least partially polygonal and / or at least partially curved course. Naturally, a particularly simple design occurs in the case of a straight-line course of the cross-sectional profile.

[0023] In a variant which is particularly simple in design, at least one supporting membrane element is configured in the manner of a thin-walled annular disk or in the manner of a thin-walled hollow conical frustum, whereby an arrangement which is particularly easy to produce is obtained.

[0024] In principle, the arrangement of the supporting film elements can be selected in any suitable manner and in such a way that the pairing of the optical element and the holding device, in particular the holding unit, is adapted to obtain the desired decoupling and / or equalization of the stiffnesses within the individual holding units. In certain advantageous variants, in a cross-sectional plane extending in the radial direction and perpendicular to the circumferential direction, at least one supporting film element is tilted by at most 10°, preferably at most 5°, more preferably at most 2° relative to the radial direction. In these variants, in particular, an advantageous narrowband stiffness distribution within the holding unit in the degree of freedom perpendicular to the main extension plane of the optical element can be obtained. In the present description, the stiffness can be influenced by the aforementioned tilt angle, wherein the stiffness perpendicular to the main extension plane increases with the tilt angle. A particularly simple configuration can be obtained if at least one supporting film element extends at least substantially parallel to the radial direction.

[0025] In some variations, at least one supporting film element has an inner segment and an outer segment spaced apart from it in the radial direction. In the present description, at least one supporting film element may have an intermediate section between the inner segment and the outer segment, which intermediate section may have a more or less large extension (in the radial direction). In addition or as an alternative, in the radial direction, at least one of the holding units (preferably a plurality of holding units, in particular all holding units) may be connected to the at least one supporting film element between the inner segment and the outer segment. In this way, the potential of this supporting film element (in terms of decoupling and / or balancing of stiffness) can be particularly well utilized. In the present description, it may be advantageous if the corresponding holding element (in the radial direction) is arranged in a central area between the inner segment and the outer segment.

[0026] This applies in particular in advantageous variants in which the at least one supporting film element is connected (in the region of the outer section) to a circumferential outer ring structure extending in the circumferential direction. In the present description, in particular, the outer ring structure can completely or partially protrude beyond the supporting film element in the direction of the optical element. If the outer ring structure is arranged at the rear side of the at least one supporting film element facing away from the front side of the at least one supporting film element (i.e., expressed in a different way, the outer ring structure faces away from the optical element), a design that is particularly easy to manufacture and assemble results.

[0027] In certain variants, it can also be advantageous if the at least one supporting film element is connected (in the region of the inner section) to a circumferential inner ring structure extending in the circumferential direction, in particular a thin-walled inner ring structure. The inner ring structure can also protrude beyond the supporting film element in the direction of the optical element. Likewise, alternatively or additionally, the inner ring structure can be arranged at the rear side of the at least one supporting film element facing away from the front side of the at least one supporting film element.

[0028] In this case, in addition to achieving the desired increase in the stiffness of the holding device, the corresponding inner ring structure and outer ring structure have the advantage that additional adaptation of the stiffness distribution within the holding unit can be carried out in a relatively simple and flexible manner through the design of the aforementioned ring structure and / or its connection to the corresponding supporting film element.

[0029] In the present description, in particular, a particularly simple connection of the holding device to the external support structure is made possible, since at least one, in particular three, of the support interface units are formed at the outer ring structure or the inner ring structure. In the present description, these support interface units can be evenly distributed along the circumference of the holding device. However, the potential for adapting the stiffness distribution works particularly well if the support interface units are distributed at irregular intervals along the circumferential direction, for example because this is predetermined by the optical elements and / or adjacent components of the imaging device.

[0030] In principle, it is sufficient that only the outer ring structure and / or the inner ring structure is to be connected to the respective supporting membrane element. In a particularly advantageous variant with a good narrowband distribution of the stiffness within the holding unit, at least one web element is provided which interconnects the outer ring structure with the inner ring structure, wherein, in the direction of the thickness dimension (of the membrane element), a gap is formed between the at least one web element and the at least one supporting membrane element.

[0031] In the present specification, the force flow between the corresponding supporting interface unit and the corresponding retaining unit can be guided and distributed in an advantageous manner by the arrangement and / or design of the web elements, which may also respectively influence or set the stiffness of the corresponding retaining unit relative to the corresponding supporting interface unit.

[0032] In the present description, the gap ensures that the decoupling potential of the supporting membrane element is not limited or (where appropriate) influenced in a defined manner. In the present description, the gap may extend over at least 50%, preferably at least 70%, more preferably 90% to 100% of the length of the web element between the outer ring structure and the inner ring structure. Naturally, the region in which no gap exists (i.e. in which the web element contacts the supporting membrane element) then limits the deformability of the supporting membrane element in this region. Therefore, this region has the effect of increasing the stiffness. This reinforcing effect can also be used to locally tune the stiffness by locally closing the gap.

[0033] Depending on the stiffness distribution to be achieved in the holding unit, a single web element may be sufficient. In certain variants, at least one pair of web elements assigned to one another is provided, wherein the two web elements of the at least one pair engage the inner ring structure immediately one after the other in the circumferential direction; this allows a particularly advantageous setting of the force flow to be achieved and thus of the stiffness distribution. It is understood that, depending on the stiffness distribution to be achieved, in principle any number of pairs of web elements may be provided. A particularly advantageous configuration generally occurs if three pairs of such web elements assigned to one another are provided.

[0034] In the case of multiple pairs of web elements, web elements of different pairs may cross.However, it may be particularly advantageous if the two web elements of at least one pair are joined to the outer ring structure immediately one after the other, ie if there is no such crossing of the web elements.

[0035] The arrangement or distribution of the web elements over the circumference can be carried out in any suitable manner, depending on the stiffness distribution in the holding unit to be obtained. In a preferred variant, at least one pair of two web elements engages the outer ring structure between two supporting interface units that follow one another in the circumferential direction. This allows a particularly advantageous distribution or setting (in one or more degrees of freedom) of the force flow and thus of the stiffness to be obtained between the supporting interface unit and the holding unit.

[0036] In principle, the two web elements of a respective pair may have any suitable alignment with respect to each other to obtain the desired stiffness distribution. Preferably, the two web elements of at least one pair each define a longitudinal axis, and the two longitudinal axes extend at a mutual inclination of at most 10°, preferably at most 5°, more preferably at most 2°, in particular 0° in a plan view of the main extension plane (wherein, thereby, they then extend parallel to each other or possibly colinearly with each other).

[0037] In addition or as an alternative, the two web elements of the corresponding pair may also be aligned in any suitable manner relative to the two ring structures and / or the support interface units. In an advantageous variant, the two web elements of at least one pair each define a longitudinal axis, wherein, in a plan view of the main extension plane, at least one of the two longitudinal axes, preferably each of the two longitudinal axes, extends with an inclination of at most 30°, preferably at most 10°, more preferably at most 2° relative to a connecting line connecting two support interface units at the outer ring structure that are immediately successive to each other in the circumferential direction and between which the corresponding web elements (of the pair) are engaged. In the present description, within the meaning of the disclosure of the invention, the connecting line between the two support interface units is preferably defined by the connection between the attack points of the resulting support forces (of the support structure of the imaging device) at the corresponding support interface units. In this way, a particularly advantageous distribution of the force flow between the support interface unit and the holding unit may be obtained, and thus an advantageous narrow-band stiffness distribution (in one or more degrees of freedom) between the holding units may be obtained.

[0038] In a further variant, at least one supporting film element is connected at its rear side facing away from its front side to a circumferential supporting ring structure extending in the circumferential direction. In the present description, the supporting interface units, in particular three supporting interface units, are then preferably formed at the supporting ring structure. In the present description, a uniform distribution of the supporting interface units over the circumference can also be provided. However, it is particularly advantageous if the supporting interface units are distributed at irregular intervals along the circumferential direction.

[0039] In this design, it can be provided in particular that at least one supporting membrane element is permanently connected to the supporting ring structure, i.e. there is no gap between the supporting ring structure and the supporting membrane element. However, it is understood that in a further variant, such a gap can also be provided at least in sections, as has already been described above in conjunction with the web element, in order to at least in sections release the deformation capacity of the supporting membrane element in this region.

[0040] In these designs, the force flow between the support interface unit and the individual holding units, and thus the stiffness distribution within the holding units, can also be set by the design and / or profile of the support ring structure. To this end, in some variants, the distance of the support ring structure from the inner section of at least one support membrane element, in particular from the inner edge of at least one support membrane element, varies along the circumferential direction between at least two, in particular all, support interface units that follow one another in the circumferential direction.

[0041] Furthermore, it is advantageous if the support ring structure connects at least two (preferably all) support interface units which follow one another in the circumferential direction substantially along the shortest path without protruding inwards in the radial direction beyond the inner edge of at least one support membrane element. This allows a particularly advantageous force flow distribution to be achieved.

[0042] It will be appreciated that for the holding device, a combination of at least one supporting membrane element and a supporting ring structure may in principle be sufficient. However, in a preferred variant, the supporting ring structure is connected on the rear side facing away from the supporting membrane element to at least one reinforcing membrane element extending mainly in the circumferential direction and in the radial direction. This can advantageously increase the stiffness of the holding device as a whole, so that in particular advantageous high resonance frequencies of the holding device occur.

[0043] In principle, the reinforcing film element can be designed in any suitable desired manner. In particular, it can be configured in a manner similar to or even identical to the supporting film element. Preferably, at least one reinforcing film element is configured in the manner of a thin-walled annular disc or in the manner of a thin-walled hollow conical frustum. Furthermore, in a cross-sectional plane extending in the radial direction and perpendicular to the circumferential direction, at least one reinforcing film element may additionally or alternatively extend with an inclination of at most 10°, preferably at most 5°, more preferably at most 2° relative to the radial direction. In the present description, it is also particularly advantageous if at least one reinforcing film element extends at least substantially parallel to the radial direction. With regard to the design and arrangement of the reinforcing film elements, the explanations given above with regard to the supporting film element also apply in principle, so reference is made in this regard.

[0044] In these designs, the holding units can in principle also be used for holding any suitable form of configuration of the optical element. In designs with a rearward support ring structure, preferably, at least one of the two holding units positioned closely together in the circumferential direction (preferably each of the holding units) is connected to at least one supporting film element via a decoupling section. This can easily ensure that the deformation capacity of the supporting film element is limited by the rearward support ring structure and compensated by the decoupling section. In the present description, in principle, the decoupling via the decoupling section can have any design and can be matched to the required one or more degrees of freedom respectively. Generally, it is particularly advantageous if the decoupling section releases the degree of freedom of tilting about a tilting axis parallel to the radial direction.

[0045] It will be appreciated that, in principle, a film element within the meaning of the disclosure of the present invention is a thin-walled element, the thickness dimension of which is significantly smaller (usually by at least one order of magnitude) than its dimensions in the other two directions in space. Preferably, in a cross-sectional plane perpendicular to the circumferential direction, a width dimension of at least one supporting film element is defined, wherein the thickness dimension of at least one supporting film element is 2% to 30%, preferably 5% to 25%, more preferably 10% to 20% of the width dimension of at least one supporting film element. This allows, with regard to the narrowband stiffness distribution to be obtained in the holding unit, particularly advantageous properties to be obtained. In the present description, it is understood that the absolute width dimension may have an influence, wherein the corresponding thickness dimension can also increase with increasing width dimension. In any case, it is preferred that the stiffness of the supporting film element, in particular in the direction perpendicular to the main extension plane, is at least one order of magnitude smaller than the stiffness of the adjacent parts of the base unit (in the corresponding spatial direction).

[0046] Additionally or as an alternative, the thickness dimension of at least one supporting film element may vary in the circumferential direction, wherein the thickness dimension may vary in particular depending on the angular distance to the nearest supporting interface unit in the circumferential direction. In the present description, it may be provided in particular that the thickness dimension increases with increasing angular distance to the nearest supporting interface unit. By means of such a variation of the thickness dimension, it is possible to finely set the deformation properties of the respective supporting film element in each case and thus (either by itself or together with the other measures described herein) obtain the desired narrowband stiffness distribution within the holding unit. Additionally or as an alternative, it is naturally also possible to vary the thickness dimension of at least one supporting film element in the radial direction for this purpose. In the present description, the thickness dimension may vary in particular depending on the desired stiffness profile of the supporting film element in the radial direction.

[0047] In addition or as an alternative, at least one supporting film element may have at least one through hole in at least one region located between two adjacent holding units in the circumferential direction, in particular in each region between two adjacent holding units. This naturally also results in corresponding options for influencing the deformation properties of the respective supporting film element and thus the narrowband stiffness distribution in the holding units.

[0048] Preferably, each holding unit comprises a holding interface unit for connection to the optical element, wherein the holding interface unit for each holding unit defines a first stiffness in a first direction perpendicular to the main extension plane and a second stiffness about an axis parallel to the radial direction relative to a respective one of the supporting interface units. In the present description, the holding device, in particular the base unit, and in particular the at least one supporting film element is then configured such that, for at least one supporting interface unit, preferably for all supporting interface units, and for a holding unit group comprising at least 80%, preferably at least 90%, more preferably 95% to 100% of the holding units, the variation of the first stiffness among the holding units of the holding unit group is at most 900%, preferably at most 100%, more preferably at most 10% to 1% of the minimum first stiffness of the holding units of the holding unit group. In general, it is required that the variation of the first stiffness among the holding units of the holding unit group is less than 1% of the minimum first stiffness of the holding units of the holding unit group. In this way, a particularly advantageous narrowband stiffness distribution is advantageously obtained in a first direction, ie perpendicularly to the main extension plane of the optical element.

[0049] It is understood that for a single degree of freedom, in particular the degree of freedom in which the main impact load is expected, this adaptation of the stiffness distribution among the holding units may be sufficient. Preferably, this adaptation is also carried out in further degrees of freedom. Likewise, it is naturally possible to also only adapt in one or more other degrees of freedom.

[0050] Thus, in certain variants, the holding device, in particular the base unit, and in particular the at least one supporting film element may then be configured such that, for at least one supporting interface unit, preferably for all supporting interface units, and for a further group of holding units comprising at least 80%, preferably at least 90%, more preferably 95% to 100% of the holding units, the second stiffness varies among the holding units of the further group of holding units by at most 900%, preferably at most 100%, more preferably at most 10% to 1% of the minimum second stiffness of the holding units of the further group of holding units. It will be appreciated that, as just mentioned above, the two groups of holding units for the first stiffness (i.e. the first group) and the second stiffness (i.e. the second group) may be identical. However, they may also differ for one or more holding units.

[0051] In principle, the holding unit can be designed in any suitable way to hold the optical element during operation. In the present description, basically, friction and / or positive and / or adhesive connection techniques can be used individually or in any desired combination. Thus, for example, the holding unit can be designed such that a customary adhesive connection (e.g. adhesive bonding or the like) is used to connect the optical element.

[0052] In a preferred variant, a detachable connection is used. In the present description, a holding unit which holds the optical element via a separate clamping connection in each case is preferred. In the present description, a corresponding clamping connection ensures simple releasability of the connection and, therefore, simple replaceability of the optical element. Moreover, the clamp has the advantage that the holding force resulting therefrom (i.e. the friction between the clamping surfaces) can be set with relatively high precision via the contact forces at the clamping surfaces. As a result, the risk that the impact load expected in the worst-case scenario of the holding unit exceeds the holding force of the aforementioned holding unit can be reliably reduced without having to provide a large safety factor and, therefore, without having to increase the size of the holding unit. As a result, despite the simplification of the holding unit, the impact safety or reliability against failure of the system under impact loads can still be advantageously improved.

[0053] In principle, the clamping connection between the respective holding unit and the optical element can be established in any suitable manner. In particular, the frictional engagement required for clamping between one or more respective contact surfaces of the holding unit and the optical element can be achieved in any suitable manner. Thus, a single clamping element can be provided for each holding unit, which is pressed against the corresponding contact surface on the optical element by means of suitable tensioning means in order to obtain a clamping frictional engagement. For example, the clamping element can be pre-tensioned against the optical element by its own support on the base unit. Corresponding reaction forces can then be applied by one or more adjacent holding units, so that the contact forces acting on the optical element in the assembled state at least partially offset each other, but at least offset each other as a whole, and a defined position and orientation of the optical element is achieved.

[0054] A particularly simple design results if at least one of the holding units, preferably each holding unit, comprises a holding interface unit for connection to the optical element, wherein the holding interface unit comprises in particular a first clamping element and a second clamping element. In the present description, the first clamping element and the second clamping element merely bear against one another for the purpose of establishing a clamped connection, wherein a holding interface section of the optical element is particularly easy to clamp between the first clamping element and the second clamping element. Preferably, this configuration is selected for each holding unit, since a particularly simple design results overall in this case.

[0055] A particularly advantageous variant with a low risk of introducing parasitic stresses into the optical element occurs if the first clamping element and the second clamping element are supported against one another for the purpose of establishing the clamping connection by means of a simple tensioning element. In the present description, the tensioning element can be designed in the form of a clamping bracket or in the form of a tension rod, for example. Preferably, the tensioning element projects through a recess in the interface section, so that a particularly uniform distribution of the clamping forces, in particular locally, can be achieved. In the present description, the tensioning element preferably projects through the recess in the interface section with play in order to avoid contact between the tensioning element and the interface section of the optical element, which could otherwise lead to parasitic stresses in the optical element.

[0056] Preferably, a compensating spring device is provided which is configured to reduce the tensioning force loss in the tensioning element. In principle, this compensating spring device can be designed in any suitable desired manner. For example, it can easily be designed in the manner of a cup spring or a cup spring packet (sometimes also referred to as a Belleville washer or a Belleville washer packet, respectively).

[0057] In principle, the tensioning element can have any suitable design for obtaining a support of the clamping elements against each other and thus a clamping of the interface section. As mentioned, this may involve a clamping bracket which engages and supports the two clamping elements around the two clamping elements. A particularly simple and compact configuration results if the tensioning element comprises a threaded section which is screwed into one of the clamping elements for support purposes. In the present description, it is particularly advantageous if at least one of the clamping elements is connected to the base unit via a connecting section, wherein the connecting section is then preferably configured such that it limits the degree of freedom of rotation about an axis extending substantially parallel to the longitudinal axis of the threaded section. This ensures that the connecting section absorbs at least a large part of the tightening torque of the threaded connection in a simple manner, so that no parasitic stresses or only small parasitic stresses are introduced into the optical element in this respect.

[0058] It is understood that each holding unit may have a holding interface unit for connecting the optical element, and that the respective holding interface unit may in principle be connected to the base unit in any suitable manner. In particular, parts of the holding interface unit (such as, for example, one of the clamping elements) may only be indirectly connected to the base unit via the aforementioned tensioning element, while other parts (such as, for example, another clamping element) may be directly connected to the aforementioned base unit. Preferably, at least one of the holding interface units, in particular each of the holding interface units, is connected to the supporting film element via a connecting section. If the use is performed by the aforementioned clamping elements, it is possible, for example, that the first clamping element is to be connected to the supporting film element via a connecting section and / or that the second clamping element is to be connected to the supporting film element via a connecting section.

[0059] It is understood that the first clamping element and the second clamping element may be connected to the base unit via a common connecting section. However, in other variations, the first clamping element may be connected to the base unit via the first connecting section, and the second clamping element (if necessary) may also be connected to the base unit via a (separate) second connecting section. In the present description, it may be advantageous if the first connecting section and the second connecting section extend substantially parallel to each other, since this achieves a configuration that is particularly easy to produce and assemble, but nevertheless has advantageous stiffness in certain degrees of freedom from a dynamic point of view. In addition or as an alternative, the first connecting section and the second connecting section can be configured in the form of parallel guides that guide the clamping elements that are supported against each other substantially parallel to the radial direction. In these two variations, the radial compliance described above can be obtained (for the purpose of thermal deformation decoupling), wherein the stiffness in the remaining degrees of freedom is high, which is dynamically advantageous under certain conditions. However, under certain conditions, such a high stiffness of the connection may also be counterproductive due to the possibility of relatively high parasitic stresses in the optical element in the event of deformation of the holding device.

[0060] In principle, the connecting section can be designed in any desired suitable manner. Thus, for example, the connecting section can be configured in the manner of a leaf spring. This results in a particularly simple, compact and cost-effective variant. Additionally or as an alternative, the connecting section can be configured to be compliant in the radial direction (of the optical element). This is particularly advantageous if the optical element and the holding device have different coefficients of thermal expansion. The radial compliance then allows a good decoupling of thermal deformations to be obtained between the optical element and the holding device. Additionally or as an alternative, the connecting section can extend substantially in a plane perpendicular to the radial direction. This also allows a particularly cost-effective and compact configuration to be obtained.

[0061] In certain variants, the connecting section is configured such that it limits the degree of freedom of rotation about an axis extending substantially parallel to the radial direction. In particular, this is advantageous if screws or the like aligned in the radial direction are used for fixing purposes, since the connecting section can then absorb at least some of the tightening torque (as already explained above for the clamping connection).

[0062] In principle, the connecting segments can be aligned in any suitable manner to achieve the above described variants. In some variants, the connecting segments define a longitudinal axis, wherein the longitudinal axis of the connecting segments then extends substantially perpendicular to the main extension plane or substantially parallel to the main extension plane. The above described radial compliance can be achieved in both cases in a particularly simple manner.

[0063] In principle, the optical element may have any design for the purpose of establishing a respective connection with a holding unit. Thus, it may comprise, for example, a single holding interface section which provides for the connection to the holding unit. In certain variants, the optical element comprises in each case a separate holding interface section for establishing this connection with the respective holding unit, the aforementioned holding interface section being used for the connection to the respective holding unit. The holding interface section of the optical element may then be clamped between two clamping elements of a holding unit, as explained above, for example.

[0064] The holding interface segment and the holding unit may be combinable with each other as desired; i.e., no specific pairing is provided between the holding interface segment and the holding unit (e.g., the optical element and the base unit with the holding unit can therefore be rotated arbitrarily relative to each other in the circumferential direction). In other variants, this specific pairing is achieved by correspondingly different designs and / or arrangements of the components. In the present description, the holding interface segment may be configured to be combinable with the first holding unit (but not with the second holding unit).

[0065] In principle, the holding interface section of the optical element can be realized at the optical element in any suitable manner. A particularly compact and simple design results if the holding interface section of the optical element is configured by a protrusion of the optical element. A plurality of holding interface sections can be formed at a common protrusion of the optical element. Furthermore, all holding interface sections can be formed at an annular protrusion of the optical element. The protrusion of the optical element may extend in the circumferential direction and / or in a direction perpendicular to a plane defined by the circumferential direction and the radial direction.

[0066] In principle, the respective holding interface section can be designed in any suitable desired manner. For example, it may be formed directly on the body of the optical element. In a variant which is preferred due to ease of execution and high precision, the respective holding interface section may be configured by a holding interface element connected to the optical element. In the present description, the holding interface element may be inserted into a recess in the optical element, wherein the aforementioned interface element may in particular be inserted into a recess in a protrusion of the optical element. This configuration may be particularly easy to manufacture. For example, the holding interface element may comprise a connecting sleeve. The connecting sleeve may comprise a convex ring, which facilitates simple and precise manufacturing and assembly.

[0067] In principle, the optical element can be manufactured in a single part or in a plurality of parts from any suitable material. Preferably, at least in the region of the protrusions, the optical element is manufactured from a ceramic material, which in particular contains SiSiC, and / or the optical element is manufactured from a material containing Zerodur, and / or from a lens material. Further suitable materials for the optical element are aluminum (Al), aluminum alloys (in particular aluminum silicon (AlSi)), beryllium (Be), beryllium alloys (in particular aluminum beryllium (AlBe)), (Ultra Low Expansion glass from Corning, NY 14831 Corning, USA), copper (Cu), molybdenum (Mo), silicon carbide (SiC), and silicon (Si). In a variation with an interface element, the interface element may preferably be made from a material comprising invar and / or stainless steel and / or molybdenum. Further suitable materials for the interface element are aluminum (Al), aluminum alloys (particularly aluminum silicon (AlSi)), beryllium (Be), beryllium alloys (particularly aluminum beryllium (AlBe)), ceramic materials (particularly SiSiC), and glass fiber-reinforced plastic (GFRP) or carbon fiber-reinforced plastic (CFRP).

[0068] In principle, the optical surface can be any refractive and / or reflective and / or diffractive optical surface. If the optical surface is a reflective optical surface, the advantages specified in the text are particularly well realized. The optical surface is then preferably arranged on a body of the optical element. The body then preferably comprises at least one protrusion, which on the side facing away from the optical surface forms an interface section to at least one of the holding units.

[0069] In principle, the base unit can also have any design. In a preferred compact variant, the base unit has an annular configuration. In the present description, the base unit can have a torus-shaped design in the simplest case. However, any other annular shape is also possible, such as a ring that is at least partially polygonal or a ring that has a combination of curved and straight sections. Usually, the form of the base unit matches the form of the optical element to be supported.

[0070] In a particularly advantageous design, the base unit defines a main extension plane of the base unit, and at least one of the holding units protrudes from the base unit in a manner substantially perpendicular to the main extension plane of the base unit. Preferably, this applies to all holding units, so that all of the aforementioned holding units protrude from the base unit in a manner substantially perpendicular to the main extension plane of the base unit. In the variant with an annular base unit, this then results in a crown-shaped design, in which the holding units protrude from the annular base unit in the manner of the tines of a crown.

[0071] In principle, the holding device may be constructed in any suitable manner from a plurality of separate parts in a so-called differential design. In certain particularly robust and highly precisely manufactured variants, the base unit has a monolithic configuration. Additionally or alternatively, the supporting membrane element may be formed monolithically with at least one of the holding units, preferably with all of the holding units.

[0072] In principle, any suitable material can be used for the holding device or its parts. This can be, for example, stainless steel, aluminum (Al), or beryllium (Be), either individually or in any desired combination. Further suitable materials are aluminum alloys, in particular aluminum silicon (AlSi), beryllium alloys, in particular aluminum beryllium (AlBe), ceramic materials, in particular SiSiC, and glass fiber reinforced plastics (GFRP) or carbon fiber reinforced plastics (CFRP).

[0073] As already mentioned above, it is preferred to have as many holding units as possible, the aforementioned number being limited by the available installation space depending on the size of the optical element. Preferably, at least 6, more preferably at least 9, more preferably 18 to 36 holding units are provided. However, depending on the size of the optical element or the available installation space, it is also possible to provide significantly more holding units. Therefore, in the case of large optical elements, as many holding units as possible are preferred. In the present description, the number of holding units may be 120 or more. The holding units may be configured in any distribution. In particular, the distribution may be adapted to the mass distribution of the optical element and / or the expected load direction (in particular of impact loads). In some variants, the holding units are configured in a substantially uniform distribution along the circumferential direction. In particular, this takes into account the situation where the load may occur in any direction.

[0074] According to a second aspect, the invention relates to an arrangement for a microlithography imaging device, in particular for use with light in the extreme ultraviolet (EUV) range, comprising a holding device for holding an optical element. The optical element comprises an optical surface and defines a main extension plane, wherein the optical element defines a radial direction and a circumferential direction. The holding device comprises a base unit and a plurality of separate holding units, in particular more than three separate holding units. The base unit for connecting the holding device to a support structure comprises a plurality of support interface units, which are spaced apart from each other in the circumferential direction. The holding units are connected to the base unit and are arranged in a manner distributed along the circumferential direction and spaced apart from each other. The holding units are configured to hold the optical element relative to the base unit, wherein each holding unit comprises a holding interface unit for connection to the optical element. With respect to a respective one of the support interface units, a first stiffness is defined for each holding interface unit of each holding unit in a first direction, in particular perpendicular to the main extension plane. The base unit comprises at least one supporting film element, wherein the holding unit is arranged on the at least one supporting film element, in particular on the front side of the at least one supporting film element facing the optical element. At least a portion of the holding device comprising at least one supporting film element is configured such that, for at least one supporting interface unit, preferably for all supporting interface units, and for a holding unit group comprising at least 80%, preferably at least 90%, more preferably 95% to 100% of the holding units, the variation of the first stiffness among the holding units of the holding unit group is at most 900%, preferably at most 100%, more preferably at most 10% to 1% of the minimum first stiffness of the holding units of the holding unit group. In general, it is desirable that the variation of the corresponding stiffness among the holding units of the holding unit group is less than 1% of the minimum corresponding stiffness of the holding units of the holding unit group.

[0075] As already mentioned above, due to the arrangement of the respective holding unit on the supporting film element, it is also possible, by the design of the supporting film element and / or by the way in which the supporting film element is connected to the supporting interface unit, to set the stiffness of the holding device between the optical unit-side attack point of the forces of the respective holding unit (at the optical element) and the support structure-side attack point of the forces of the respective supporting interface unit (at the supporting structure). It can therefore be advantageously achieved that this stiffness (in particular in certain relative degrees of freedom) is balanced to the greatest possible extent among a plurality of holding units (preferably all holding units). The greater this balance in a particular degree of freedom (thus, the smaller the differences in stiffness between the individual holding units in this degree of freedom, or the narrower the distribution of this stiffness among the holding units), the more evenly the impact loads are distributed among the holding units in the respective degree of freedom. In the ideal case, it is even possible for all holding units to obtain at least substantially the same stiffness with respect to the support structure-side attack point of the forces in the respective degree of freedom. In this case, the impact loads in the respective degree of freedom are then evenly distributed among all holding units.

[0076] It will be appreciated that this distribution of stiffness among the holding units according to the second aspect may in particular be combined arbitrarily with the features and variants (or combinations of features) as described above in the context of the aforementioned first aspect of the invention. In particular, the same advantages may be achieved as described above for the corresponding features. Therefore, explicit reference is made to the explanations given above.

[0077] The invention also relates to an optical imaging device, in particular a microlithography optical imaging device, comprising: an illumination device, the illumination device comprising a first group of optical elements; an object device for receiving an object; a projection device, the projection device comprising a second group of optical elements; and an image device, wherein the illumination device is configured to illuminate the object and the projection device is configured to project an image of the object onto the image device. The illumination device and / or the projection device comprise at least one arrangement according to the invention. This makes it possible to achieve the variants and advantages described above to the same extent, so that in this respect reference is made to the explanations given above.

[0078] Furthermore, the invention relates to a method for supporting an optical element for microlithography, in particular for use with light in the extreme ultraviolet (EUV) range, wherein an optical element (109) comprising an optical surface and defining a main extension plane is held by a holding device, wherein the optical element defines a radial direction and a circumferential direction. In this specification, the optical element is held by a plurality of separate holding units of the holding device, in particular more than three separate holding units, which are arranged in a manner distributed along the circumferential direction and spaced apart from each other with respect to a base unit of the holding device. The base unit is connected to a support structure via a plurality of support interface units spaced apart from each other in the circumferential direction. In this specification, at least one supporting film element of the base unit extends mainly along the circumferential direction and along the radial direction, wherein at least one supporting film element has a thickness dimension transverse to the circumferential direction and the radial direction. The holding unit is arranged on the front side of at least one supporting film element facing the optical element. This also makes it possible to achieve the variations and advantages described above in the context of the first aspect to the same extent, so reference is made in this respect to the explanation given above.

[0079] Furthermore, the invention relates to a method for supporting an optical element for microlithography, in particular for use with light in the extreme ultraviolet (EUV) range, wherein an optical element (109) comprising an optical surface and defining a main extension plane is held by a holding device, wherein the optical element defines a radial direction and a circumferential direction. In this specification, the optical element is held by a plurality of separate holding units of the holding device, in particular more than three separate holding units, which are arranged in a manner distributed along the circumferential direction and spaced apart from each other with respect to a base unit of the holding device. The base unit is connected to a support structure via a plurality of support interface units spaced apart from each other in the circumferential direction. Each holding unit comprises a holding interface unit, which is connected to the optical element. With respect to a respective one of the support interface units, a first stiffness in a first direction, in particular perpendicular to the main extension plane, is defined for each of the holding interface units. The holding unit is arranged on at least one supporting film element of the base unit, in particular on the front side of at least one supporting film element facing the optical element. At least a portion of the holding device comprising at least one supporting film element is configured such that, for at least one supporting interface unit, preferably for all supporting interface units, and for a holding unit group comprising at least 80%, preferably at least 90%, more preferably 95% to 100% of the holding units, the first stiffness varies among the holding units of the holding unit group by at most 900%, preferably at most 100%, more preferably at most 10% to 1% of the minimum first stiffness of the holding units of the holding unit group. This also makes it possible to achieve the variants and advantages explained above in the context of the second aspect to the same extent, so reference is made in this respect to the explanations given above.

[0080] With regard to a stress-free or defined assembly, in which parasitic stresses in the optical element are at least largely avoided, it is particularly advantageous to adopt the above method if the corresponding connection between the three holding units of the holding device and the optical element is established in a first step so that the optical element is fixed in space relative to the base element. Therefore, fixing in the manner of a conventional three-point support can be achieved first. In the present description, this may be related to three (first) holding units that are specifically designed for this initial attachment of the optical element and are different from the remaining holding units. In particular, the three (first) holding units may have a more rigid design than the remaining (second) holding units. Then, the corresponding connection between the remaining (second) holding units of the holding device and the optical element is established in a second step, which follows the first step. In the present description, the remaining (second) holding units may have a significantly lower stiffness than the three (first) holding units, in particular in the movement direction required for clamping purposes, so as to be able to compensate for production inaccuracies without generating significant restoring forces and thus parasitic stresses.

[0081] Further aspects and embodiments of the invention become apparent from the dependent claims and from the following description of preferred embodiments, which is in relation to the accompanying drawings. All combinations of disclosed features, whether or not they are the subject of a claim, are within the scope of protection of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0082] Figure 1 is a schematic illustration of a preferred embodiment of a projection exposure apparatus according to the invention, comprising a preferred embodiment of an optical arrangement according to the invention.

[0083] Figure 2 It is from Figure 1 Schematic plan view of the front side of a holding device of an arrangement according to the invention.

[0084] Figure 3 It is from Figure 2 Schematic cross-sectional view of a part (detail D) of an arrangement according to the invention (along Figure 2 line III-III in the figure).

[0085] Figure 4 It is from Figure 1 Schematic plan view of the rear side of a holding device of an arrangement according to the invention.

[0086] Figure 5 It is from Figure 2 Schematic cross-sectional view (in plan view from the rear) of a variant of the arrangement according to the invention (similar to Figure 4 of the view and along Figure 6 line VV).

[0087] Figure 6 It is from Figure 5 Schematic cross-sectional view of a part (detail D) of an arrangement according to the invention (along Figure 5 Line VI-VI in the figure).

[0088] Figure 7 It is from Figure 5 Schematic cross-sectional view of a portion of the arrangement (along Figure 6 Line VII-VII in the figure). DETAILED DESCRIPTION

[0089] First embodiment

[0090] The following references Figures 1 to 4 A preferred embodiment of a microlithography projection exposure apparatus 101 according to the invention is described, which comprises a preferred embodiment of an optical arrangement according to the invention. To simplify the following explanation, an x, y, z coordinate system is indicated in the attached drawings, the z direction corresponding to the direction of gravity. It goes without saying that any desired other orientation of the x, y, z coordinate system can be selected in further configurations.

[0091] Figure 1 1 is a schematic, not-to-scale representation of a projection exposure apparatus 101 used in a microlithography process for producing semiconductor components. The projection exposure apparatus 101 comprises an illumination device 102 and a projection device 103. The projection device 103 is designed to transfer an image of a structure of a mask 104.1 arranged in a mask unit 104 onto a substrate 105.1 arranged in a substrate unit 105 during an exposure process. For this purpose, the illumination device 102 illuminates the mask 104.1. The optical projection device 103 receives light from the mask 104.1 and projects an image of the mask structure of the mask 104.1 onto a substrate 105.1, for example a wafer or the like.

[0092] The illumination device 102 comprises an optical unit 106, which comprises an optical element group 106.1. The projection device 103 comprises a further optical unit 107, which comprises an optical element group 107.1. The optical element groups 106.1, 107.1 are arranged along the folded central ray path 101.1 of the projection exposure apparatus 101. Each optical element group 106.1, 107.1 may comprise a plurality of optical elements.

[0093] In an embodiment of the invention, the projection exposure apparatus 101 operates with exposure light in the EUV range (extreme ultraviolet radiation) with a wavelength between 5 nm and 20 nm, in particular with a wavelength of 13 nm. Therefore, the optical elements of the element groups 106.1, 107.1 of the illumination device 102 and the projection device 103 are exclusively reflective optical elements. The optical element groups 106.1, 107.1 may comprise one or more optical arrangements according to the invention, as described below based on the optical arrangement 108. The optical units 106 and 107 are each supported by a support structure 101.2.

[0094] In a further configuration of the invention, it is of course also possible (in particular depending on the wavelength of the bright light) to use any type of optical elements (refractive, reflective, diffractive), either alone or in any desired combination of optical modules.

[0095] An arrangement according to the present invention is explained below in an exemplary manner based on arrangement 108 . Figure 2 A schematic plan view of the front side of a portion of the arrangement 108 is shown, and Figure 3 A schematic cross-sectional view showing a portion of the arrangement 108 (along the Figure 2 line III-III), and Figure 4 Shown from Figure 2 A schematic plan view of the rear side of a portion of arrangement 108 .

[0096] If possible from Figure 2 And especially Figure 3 (It shows Figure 2 As can be seen from the detail D), in the example of the present invention, the arrangement 108 is an optical arrangement and comprises an optical element 109 in the form of a collector mirror of the lighting device 102; and a holding device 110 for holding the optical element 109. In this specification, Figure 2 A plan view (along the z direction) of the front side of the holding device 110 facing the optical element 109 is shown. Figure 2 , the optical element 109 is indicated by its dashed outer outline.

[0097] The optical element 109 comprises a reflective optical surface 109.1 which is formed (in a conventional manner) on one side (the front side) of a body 109.2 of the optical element 109. The optical element 109 defines a main extension plane (parallel to the xy plane or Figure 2 ), wherein the optical element 109 defines a radial direction R and a circumferential direction U.

[0098] In the example of the present invention, the holding device 110 comprises a base unit 110.1 and separate holding units 110.2, wherein the holding units 110.2 are connected to the base unit 110.1 and are arranged in a manner distributed along the circumferential direction U and spaced apart from each other. The holding units 110.2 hold the optical element 109 in a predeterminable position and orientation with respect to the base unit 110.1. In the example of the present invention, each holding unit 110.2 establishes a clamping connection between the optical element 109 and the base unit 110.1, the aforementioned clamping connection being separate from the other holding units 110.2. However, it is understood that any other connection technology may be adopted in other variations between the respective holding units 110.2 and the optical element 109.

[0099] As already mentioned, it is preferred to have as many holding units 110.2 as possible, the aforementioned number being limited by the available installation space depending on the size of the optical element 109. In the example of the invention, 18 holding units 110.2 are provided. However, in other variants, a different number may also be provided. In particular, some variants may provide at least 6, preferably at least 9, and more preferably 18 to 36 holding units 110.2.

[0100] In the example of the invention, the holding units 110.2 are arranged evenly distributed at angular intervals of 20° in each case along the circumferential direction U. This makes it possible for the attachment to always have substantially the same behavior regardless of the load direction of the loads introduced into the optical element (e.g. impact loads) or without a specific load direction in which impact loads involve an increased risk of misalignment of the optical element 109.

[0101] However, it is understood that in other variants, the holding units 110.2 may be configured with an at least partially irregular distribution as desired. In particular, the distribution of the holding units 110.2 may be adapted in these cases to the mass distribution of the optical element 109 and / or to the expected accelerations of the arrangement 108 and the load directions resulting therefrom. The holding units 110.2 may be exposed to higher loads in certain areas, in particular in the case of an asymmetric optical element 109, so that it may be advantageous to have an asymmetric distribution of the holding units 110.2 with a concentration in these areas (i.e. a locally larger number of holding units per circumferential angle) where higher loads are expected during operation.

[0102] In addition, the base unit 110.1 includes a plurality of support interface units 110.3, which are spaced apart from each other in the circumferential direction U and are used to connect the holding device 110 to the support structure 102.1 of the lighting device 102. In the example of the present invention, three support interfaces 110.3 are provided. However, it can be understood that any other (fewer or more) number of support interfaces 110.3 can be provided in other variations.

[0103] If possible from Figure 3 It can be seen that the base unit 110.1 comprises a supporting film element 110.4. The supporting film element 110.4 extends mainly along the circumferential direction U and along the radial direction R, wherein it has a thickness dimension D transversely (more precisely, in the present example, perpendicularly) to the circumferential direction U and the radial direction R. In the present description, the holding unit 110.2 is arranged on the front side of the supporting film element 110.4 facing the optical element 109.

[0104] As explained in more detail below, in addition, the holding unit 110.2 is arranged on the supporting film element 110.4 so that, by the design of the supporting film element 110.4 and / or by the manner in which the supporting film element 110.4 is connected to the supporting interface unit 110.3, it is possible to set the stiffness of the holding device 110 between the optical unit side attack point of the force of the corresponding holding unit 110.2 (at the optical element 109) and the support structure side attack point of the force (of the supporting structure 102.1) at the corresponding supporting interface unit 110.3.

[0105] It can therefore be advantageously achieved that this stiffness (in particular in certain relevant degrees of freedom) is balanced among a plurality of holding units 110.2 to the greatest possible extent, which is most advantageously the case for all holding units. The greater this equalization of the stiffness in a specific degree of freedom (thus the smaller the difference in stiffness between the individual holding units 110.2 in this degree of freedom, or the narrower the distribution of this stiffness among the holding units 110.2), the more evenly the impact load is divided among the holding units 110.2 in the respective degree of freedom. In the ideal case, with respect to the supporting structure-side attack point of the force at the supporting interface unit 110.3, it is even possible for all holding units 110.2 (in the respective degree of freedom) to obtain at least substantially the same stiffness. In this case, the impact load in the respective degree of freedom is then evenly distributed among all holding units 110.2.

[0106] Thus, at the holding unit 110.2, the risk that the expected impact load will exceed the maximum achievable holding force of the aforementioned holding unit in the worst case can be reliably reduced without having to provide a large safety factor and thus without having to increase the size of the holding unit 110.2. Therefore, despite having a relatively simple design of the holding unit 110.2, the impact safety or reliability against failure of the system under impact loads can still be advantageously increased. Thus, the holding unit 110.2 can have a simpler and therefore more space-saving design, which in turn helps to further increase the number of holding units 110.2. Ultimately, this may allow an advantageously large number of holding units 110.2 to be achieved, wherein the impact loads are evenly distributed among the holding units 110.2.

[0107] A further advantage of the supporting film element 110.4 is the fact that it decouples the holding units 110.2 from one another with respect to the degree of freedom of tilting, the tilting axes of which are located in the supporting film element 110.4. In particular, it is possible to achieve a decoupling about a tilting axis extending parallel to the radial direction R. This is due in particular to the fact that the supporting film element 110.4 can be deformed relatively easily by bulging. In this way (for example, in the event of a deformation of the base unit 110.1), the holding units 110.2 can be tilted relative to one another about these tilting axes, so that the introduction of parasitic stresses caused by the deformation into the optical element 109 via the holding units 110.2 is reduced.

[0108] In the example of the invention, the supporting film element 110.4 is designed in a particularly simple manner in the form of a thin-walled annular disk. However, it is understood that an annular circumferential film need not be used in other variants. Instead, for example, a plurality of individual supporting film elements 110.4 configured in the form of ring segments may be provided.

[0109] Furthermore, it is understood that the supporting film element 110.4 may also be configured in the form of a thin-walled hollow conical frustum in other variants. Likewise, in other variants, the supporting film element 110.4 may have another suitable design and arrangement for obtaining the functions of decoupling and balancing the stiffness among the individual holding units 110.2 described above. For example, any winding and / or folding configuration of the supporting film element 110.4 may be implemented (in a cross-sectional plane extending perpendicular to the circumferential direction U) to set the stiffness or compliance of the holding device 110 in a targeted manner in (one or more) specific degrees of freedom. Therefore, the cross-sectional profile of the supporting film element 110.4 may then have a straight direction at least in sections and / or a polygonal direction at least in sections and / or a curved direction at least in sections. Naturally, a particularly simple design occurs in the case of a straight-line direction of the cross-sectional profile, as is the case in the example of the present invention.

[0110] The design of the supporting film element 110.4 as an annular disk allows the supporting film element 110.4 to extend in a cross-sectional plane (which extends in the radial direction R and perpendicular to the circumferential direction U, parallel to the radial direction R, and thus at an inclination of 0° relative to the radial direction R), because this results in a particularly good adaptation to the geometric conditions of the optical element 109 and the holding unit 110.2 in the example of the invention. In the case of the invention, this achieves an advantageous narrowband stiffness distribution in the holding unit 110.2, in particular in the degree of freedom perpendicular to the main extension plane of the optical element 109 (i.e. along the z direction in the example of the invention).

[0111] However, it is understood that the arrangement of the supporting film elements 110.4 can also be configured differently in other variants to obtain a configuration that matches the pairing of the optical element 109 and the holding device 110, in particular the holding unit 110.2, thereby obtaining the required decoupling and / or equalization of the stiffness for the individual holding units 110.2. Preferably, in a cross-sectional plane extending in the radial direction R and perpendicular to the circumferential direction U, the respective supporting film element 110.4 extends with an inclination of at most 10°, preferably at most 5°, more preferably at most 2° relative to the radial direction. In the same way, depending on the use case, it may also be advantageous to obtain a narrowband stiffness distribution in the holding unit 110.2 in a certain degree of freedom, in particular in a degree of freedom perpendicular to the main extension plane of the optical element 109.

[0112] In the example of the invention, the supporting film element 110.4 has an inner section 110.5 in the radial direction R and an outer section 110.6 at a distance therefrom, wherein a middle section 110.7 is located between the inner section 110.5 and the outer section 110.6, in the region of which the holding unit 110.2 is connected to the supporting film element 110.4. In this way, the potential (decoupling and / or equalization of stiffness) of the supporting film element 110.4 can be particularly well utilized.

[0113] In the example of the present invention, in the area of ​​the outer segment 110.6, the supporting film element 110.4 is connected to a circumferential outer ring structure 110.8 extending in the circumferential direction U, and in the area of ​​the inner segment 110.5, the aforementioned supporting film element 110.4 is connected to a circumferential thin-walled inner ring structure 110.9 extending in the circumferential direction U.

[0114] In the example of the present invention, both the outer ring structure 110.8 and the inner ring structure 110.9 are arranged at the rear side of the supporting film element 110.4 facing away from the front side of the supporting film element 110.4. Therefore, both the outer ring structure 110.8 and the inner ring structure 110.9 are thus directed away from the optical element 109. However, it is understood that in other variants, the outer ring structure 110.8 and / or the inner ring structure 110.9 may completely or partially protrude beyond the supporting film element 110.4 in the direction of the optical element 109.

[0115] In the present description, the position at which the holding unit 110.2 is connected to the supporting membrane element 110.4 in the radial direction R has an influence on the decoupling achieved by the supporting membrane element 110.4 and on the stiffness between the holding unit 110.2 and the respective supporting interface unit 110.3. The closer this connection point of the holding unit 110.2 is to one of the reinforcing ring structures 110.8, 110.9, the lower the degree of decoupling or the higher the value of this stiffness. Thus, in general (i.e. for any configuration), a particularly high degree of decoupling is achieved if the distance between this connection point of the holding unit 110.2 and the reinforcing structure (e.g. one of the ring structures 110.8, 110.9) is as large as possible. In the example of the invention, this can be achieved by virtue of the connection point of the respective holding unit 110.2 being arranged (in the radial direction R) in the central region of the supporting membrane element 110.4 (i.e. approximately centrally between the reinforcing ring structures 110.8, 110.9). It is thus clear that the position of the connection point of the holding unit 110.2 is a further parameter by means of which the stiffness distribution within the holding unit 110.2 can be set.

[0116] In addition to the desired making of the holding device 110 more rigid, each of the inner ring structure 110.9 and the outer ring structure 110.8 has the advantage that additional adaptation of the stiffness distribution among the holding units 110.2 can be carried out in a relatively simple and flexible manner through the design of the aforementioned ring structure and / or its connection to the supporting membrane element 110.4.

[0117] In the present example, the holding unit 110.2 protrudes from the base unit 110.1 substantially perpendicularly to the main extension plane of the base unit 110.1. This results in a crown-like design, in which the holding unit 110.2 protrudes from the annular base unit 110.1 in the manner of the tines of a crown.

[0118] In the present description, the holding device 110 is particularly simply connected to the outer support structure 102.1 by means of the outer ring structure 110.8 of the support interface units 110.3 formed at the outer ring structure 110.8. However, it will be appreciated that in other variants, at least some of the support interface units 110.3 may also be formed at the inner ring structure 110.9. In particular, all the support interface units 110.3 may also be formed at the inner ring structure 110.9.

[0119] In some variants, the support interface units 110.3 may be evenly distributed along the circumference of the holding device 110. However, in the present example, since the support interface units 110.3 are distributed at irregular intervals along the circumferential direction U, the adaptation potential in terms of stiffness distribution works particularly well, for example because this is predetermined by the optical element 109 and / or adjacent components of the imaging device 101.

[0120] In order to obtain a good narrowband distribution of stiffness in the holding unit 110.2 (with respect to the support interface unit 110.3), web elements 110.10 are provided in the exemplary embodiment of the invention, which are arranged in pairs 110.11 and interconnect the outer ring structure 110.8 with the inner ring structure 110.9 (see in particular Figure 4 ). In the present description, a gap 110.12 is formed between the web element 110.10 and the supporting film element 110.4 in each case in the direction of the thickness dimension D of the supporting film element 110.4.

[0121] In this specification, the force flow between the corresponding support interface unit 110.3 and the corresponding holding unit 110.2 (in Figure 4 The respective web elements 110.10 (indicated schematically only) can be guided and distributed in an advantageous manner by the arrangement and / or design of the respective web elements 110.10, which may also influence or set the stiffness of the respective retaining unit 110.2 relative to the respective support interface unit 110.3.

[0122] In the present description, the gap 110.12 ensures that the decoupling potential of the supporting film element 110.4 is not limited or (where appropriate) influenced in a defined manner. Thus, the gap can extend between the outer ring structure 110.8 and the inner ring structure 110.9 over at least 50%, preferably at least 70%, more preferably 90 to 100% of the length of the web element 110.10. Naturally, the region in which no gap 110.12 exists (i.e. in which the web element 110.10 contacts the supporting film element 110.4) in this case limits the deformability of the supporting film element 110.4 in this region. Therefore, this region has the effect of increasing the stiffness.

[0123] In the example of the invention, three pairs 110.11 of mutually assigned web elements 110.10 are provided. However, it is understood that, depending on the stiffness distribution to be obtained, in principle any number of pairs 110.11 of web elements 110.10 may be provided.

[0124] In the example of the invention, the two web elements 110.10 of a corresponding pair 110.11 engage the inner ring structure 110.9 immediately one after another in the circumferential direction U. This allows the force flow and thus the stiffness distribution to be set in a particularly advantageous manner. In addition, the two web elements 110.10 of a corresponding pair 110.11 also engage immediately one after another on the outer ring structure 110.8. Therefore, the web elements 110.10 of different pairs 110.11 do not cross each other. However, it is understood that in other variants, the web elements 110.10 of different pairs 110.11 can also cross (if necessary); naturally, this then produces a further reinforcement of the holding device 110.

[0125] The arrangement or distribution of the web elements 110.10 over the circumference of the holding device 110 can be implemented in any suitable manner, depending on the stiffness distribution in the holding unit 110.2 to be obtained. In a preferred variant as an example of the invention, two web elements 110.10 of a corresponding pair 110.11 engage in the outer ring structure 110.8 between two supporting interface units 110.3 that follow one another in the circumferential direction U. This allows a particularly advantageous distribution or setting of the force flow and thus the stiffness (in one or more degrees of freedom) to be obtained between the supporting interface unit 110.3 and the holding unit 110.2.

[0126] In the example of the invention, the longitudinal axes 110.13 of the two web elements 110.10 of the corresponding pair 110.11 extend colinearly with each other. However, in other variants, the web elements 110.10 of the corresponding pair 110.11 may also be aligned with an inclination relative to each other in order to obtain a desired stiffness distribution between the holding units 110.2. Preferably, the longitudinal axes 110.13 of the two web elements 110.10 extend with an inclination relative to each other of at most 10°, preferably at most 5°, more preferably at most 2° in a plan view on the main extension plane (see Figure 4 ).

[0127] In a plan view on the main extension plane, the two longitudinal axes 110.13 of the pair 110.11 also extend at least substantially parallel to a connection line 110.14 which connects two support interface units 110.3 that are immediately successive in the circumferential direction U at the outer ring structure 110.8, between which the web elements 110.10 of the respective pair 110.11 are joined. In the present specification, as already mentioned above, the connection line 110.14 between two support interface units 110.3 is defined by the connection between the attack points of the resulting support forces (of the support structure 102.1 of the imaging device 101) at the respective support interface units 110.3. In this way, a particularly advantageous distribution of the force flow between the support interface units 110.3 and the retaining units 110.2 and, therefore, an advantageous narrow-band stiffness distribution (in one or more degrees of freedom) between the retaining units 110.2 may be obtained.

[0128] However, it is understood that the two longitudinal axes 110.13 of the corresponding pair 110.11 may also extend at an inclination relative to each other in other variations. However, preferably, the two longitudinal axes 110.13 of the corresponding pair 110.11 extend at an inclination relative to each other of at most 30°, preferably at most 10°, more preferably at most 2°.

[0129] In the example of the invention, the supporting film element 110.4 is a thin-walled element, whose thickness dimension D is significantly smaller (usually by at least one order of magnitude) than its dimensions in the other two spatial directions. In the example of the invention, the supporting film element 110.4 defines a width dimension B in a cross-sectional plane perpendicular to the circumferential direction U, wherein the thickness dimension D of the supporting film element is 2% to 30%, preferably 5% to 25%, more preferably 10% to 20% of the width dimension B of the supporting film element 110.4. This allows particularly advantageous properties to be obtained in terms of a narrowband stiffness distribution within the holding unit 110.2 to be obtained.

[0130] In the present description, the thickness dimension D of the supporting film element 110.4 may vary along the circumferential direction U. In particular, the thickness dimension D may vary depending on the angular distance to the nearest supporting interface unit 110.3 along the circumferential direction U. In the present description, the thickness dimension D may increase as the angular distance to the nearest supporting interface unit 110.3 increases. Through this variation of the thickness dimension D, it is possible to finely set the deformation properties of the supporting film element 110.4 in each case and thus (by itself or together with other measures described herein) obtain the desired narrowband stiffness distribution within the retaining unit 110.2. In addition or as an alternative, it is naturally also possible to change the thickness dimension D of the supporting film element 110.4 along the radial direction R for this purpose. In the present description, in particular, the thickness dimension D may vary depending on the desired stiffness profile of the supporting film element to be achieved in the radial direction.

[0131] Furthermore, in some variants, the supporting film element 110.4 may be positioned in at least one region between two adjacent holding units 110.2 in the circumferential direction U, and in particular, each region between two adjacent holding units 110.2 may have at least one through hole, such as in Figure 4 Indicated by the dashed outline 113. In this way, a corresponding option of influencing the deformation properties of the supporting membrane element 110.4 and thus the narrowband stiffness distribution within the holding unit 110.2 also emerges. In this case, the size and / or position and / or form of the respective through-holes 113 make it possible to influence the stiffness particularly precisely.

[0132] If possible from Figure 3 It can be seen that in particular each holding unit 110.2 in the example of the invention has a first clamping element 110.15 (in this case an outer clamping element in the radial direction R) and a second clamping element 110.16 (in this case an inner clamping element in the radial direction R). In the present description, the first clamping element 110.15 can be connected to the base unit 110.1 via a first connecting section 110.17, as in Figure 317. However, it is also possible that there is no first connection section 110.17 and the first clamping element 110.15 is also not directly connected to the base unit 110.1. In any case, the second clamping element 110.16 is connected to the base unit 110.1 via the second connection section 110.18.

[0133] For the purpose of establishing a clamping connection to the optical element 109, the first clamping element 110.15 and the second clamping element 110.16 are supported against each other by a tensioning element 111 in the form of a tensioning screw. In the present description, the associated interface section 109.3 of the optical element 109 is respectively clamped between the first clamping element 110.15 and the second clamping element 110.16 of the corresponding holding unit 110.2.

[0134] However, the clamping connection between the respective holding unit 110.2 and the optical element 109 may also be designed differently in other variants. Thus, the frictional engagement required for clamping may also be achieved by only a single clamping element 110.15 or 110.16 per holding unit 110.2, if (where appropriate) the clamping element 110.15 or 110.16 is pressed against the associated contact surface on the interface section 109.3 of the optical element 109 by suitable tensioning means (e.g. a connecting section 110.17 or 110.18 under suitable pretensioning in the radial direction R) to obtain a clamping frictional engagement. Then, corresponding reaction forces may be applied by one or more adjacent holding units 110.2, so that the contact forces acting on the optical element 109 in the assembled state offset each other in sections, but at least as a whole, and a defined position and orientation of the optical element 109 is achieved.

[0135] In the example of the invention, the tensioning element 111 is designed in the manner of a tension rod. The tensioning element 111 projects with play through the recess 109.4 in the interface section 109.3, which results in a particularly uniform distribution of the clamping force. Due to the play between the tensioning element 111 and the interface section 109.3 in the region of the recess 109.4, contact between the tensioning element 111 and the interface section 109.3 is avoided, which could otherwise lead to parasitic stresses in the optical element 109.

[0136] Therefore, in the present description, perpendicularly to the radial direction R, only a frictional engagement of the clamping connection exists between the contact surfaces of the clamping elements 110.15, 110.16 and the associated contact surfaces of the interface section 109.3, which is precisely defined by the pretensioning of the tensioning element 111. This has the advantage that the holding force resulting from the clamping and therefore the contact force at the clamping surfaces can be set with relatively high precision by the pretensioning in the tensioning element 111.

[0137] The tensioning element 111 is guided through a through hole in the outer first clamping element 110.15 and through the recess 109.4. In the example of the invention, the tensioning element 111 comprises a threaded section 111.1 which is screwed into a corresponding threaded hole in the inner second clamping element 110.16 for support purposes. In contrast, the screw head 111.2 of the tensioning element 111 rests on the outer first clamping element 110.15.

[0138] In the example of the invention, a compensating spring device 111.3 is provided between the screw head 111.2 and the first clamping element 110.15, the aforementioned compensating spring device being configured to reduce the tensioning force loss in the tensioning element 111. In principle, this compensating spring device 111.3 can be designed in any suitable desired manner. For this purpose, in the example of the invention, the compensating spring device 111.3 is designed only in the manner of a cup spring or a cup spring bundle. However, it is also possible to use any other suitable compensating spring device.

[0139] The first connecting section 110.17 can be connected to the second connecting section 110.18, such as Figure 3 . It is advantageous if the respective connecting sections 110.17, 110.18 of the two clamping elements 110.15, 110.16 then limit the degree of rotational freedom about an axis extending substantially parallel to the longitudinal axis of the threaded portion 111.1. This ensures that the respective connecting sections 110.17, 110.18 can absorb at least a large part of the tightening torque of the threaded connection in a simple manner, so that no parasitic stresses or only very small parasitic stresses are introduced into the optical element in this range.

[0140] For this purpose, as in the example of the invention, the respective connecting sections 110.17, 110.18 can be configured in the manner of leaf springs, which in the aforementioned example of the invention extend substantially in a plane perpendicular to the radial direction R. This results in a particularly simple and compact configuration. Moreover, the respective connecting sections 110.17, 110.18 are thereby compliant in the radial direction R. This is particularly advantageous when the optical element 109 and the holding device 110 have different coefficients of thermal expansion. This radial compliance then allows a good decoupling of thermal deformations to be obtained between the optical element 109 and the holding device 110.

[0141] The first connecting section 110.17 and the second connecting section 110.18 extend substantially parallel to each other, which results in a configuration that is particularly easy to produce and assemble. Moreover, this configuration is advantageous from a dynamic point of view, since it is advantageously rigid in the degrees of freedom parallel to the planes of the respective connecting sections 110.17, 110.18.

[0142] In the case of an undulating deformation of the holding device 110 caused by gravity (between the support interface units 110.3 at the connection support structure 102.1), there can be a tilting of the holding units 110.2 relative to one another about a tilting axis which is in each case parallel to the radial direction R. In this case, the stiffness of the connection section 110.18 will lead to a change in the distance between adjacent clamping elements 110.16, so that parasitic stresses are introduced into the optical element 109. Since the support film element 110.4 can absorb the occurring restraining forces by elastic deformation in the form of local bulges, the connection of the connection section 110.18 to the support film element 110.4 can significantly reduce these parasitic stresses.

[0143] If the first connecting section 110.17 is also configured as a rectilinear leaf spring extending parallel to the second connecting section 110.18, the parallel guidance can be realized in a further variant with the first connecting section 110.17 and the second connecting section 110.18. In the present description, a slightly modified design is then advantageous, in which the two leaf springs are constrained to the supporting membrane element 110.4. The clamping elements 110.15, 110.16, which are supported against each other, are then thereby guided substantially parallel to the radial direction R. Thus, the radial compliance described above (for the purpose of thermal deformation decoupling) can be obtained in the remaining degrees of freedom with a dynamically advantageous high stiffness.

[0144] In the present example, the corresponding interface section 109.3 of the optical element 109 is formed at a protrusion 109.5 extending circumferentially (in the circumferential direction U) in an annular manner on the rear side (facing away from the optical surface 109.1) of the optical element 109. In the present specification, the protrusion 109.5 extends in the circumferential direction U and in a direction perpendicular to the main extension plane of the optical element 109 (i.e., the plane defined by the circumferential direction U and the radial direction R).

[0145] In the inventive example, all interface segments 109.3 are formed at a common protrusion 109.5. However, in other variants, the protrusion 109.5 may also be interrupted in the circumferential direction U, so that the interface segments 109.3 may be provided at separate circumferential segments of the protrusion 109.5, in each case individually or in groups.

[0146] In the example of the invention, a design which is particularly easy to implement and has a high degree of precision occurs by virtue of the fact that the respective interface section 109.3 is formed by an interface element 109.6 which is connected to the optical element 109 in the region of the protrusion 109.5. The interface element 109.6 is configured as a connection sleeve with a raised ring 109.7 which is inserted into a recess 109.8 of the protrusion 109.5 of the optical element 109 and is attached thereto in a suitable manner, such as by means of an adhesive connection by adhesive bonding, welding or the like.

[0147] Since the connecting sleeve 109.6 forms the contact surfaces to the clamping elements 110.15, 110.16, this configuration is particularly easy to produce. These contact surfaces to the clamping elements 110.15, 110.16 are substantially easier to create at the end of the connecting sleeve 109.6 than at the projection 109.5. Therefore, only the radial recess 109.8 needs to be produced on the projection 109.5, wherein the connecting sleeve 109.6 can be relatively easily mounted with sufficiently high precision.

[0148] However, it is understandable that in other variations, the corresponding interface segment 109.3 may also be formed directly at the body 109.2 of the optical element 109, in particular at the protrusion 109.5.

[0149] The interface segment 109.3 and the holding unit 110.2 may be combined with each other as required; that is, the specific pairing between the interface segment 109.3 and the holding unit 110.2 cannot be specified (for example, the optical element 109 and the base unit 110.1 having its holding unit 110.2 can therefore be rotated arbitrarily relative to each other along the circumferential direction U).

[0150] However, in other variations, this specific pairing can be defined by correspondingly different designs and / or arrangements of the components of the interface segment 109.3 and the holding unit 110.2. In this case, the interface segment 109.3 can be configured such that, although it can be combined with a (first) holding unit 110.2, it cannot be combined with another (second) holding unit 110.2.

[0151] With a view to a stress-free or defined assembly in which parasitic stresses in the optical element 109 are at least largely avoided, it is particularly advantageous here if a corresponding clamping connection between the three holding units 110.2 of the holding device 110 and the optical element 109 is initially established in a first step during assembly so that the optical element is fixed in space relative to the base unit 110.1. Thus, fixing in the manner of a customary three-point support can thus be achieved first.

[0152] This may be achieved by three (first) holding units 110.2 which are specifically designed for this initial attachment of the optical element 109 and which are different from the remaining holding units 110.2. In the example of the invention, these may be three positions 112.1, 112.2 and 112.3 (see Figure 2 ) holding units 110.2, which are each arranged in a manner rotated 120° relative to each other in the circumferential direction. In particular, these three (first) holding units 110.2 may have a substantially more rigid design than the remaining (second) holding units 110.2.

[0153] Then, a corresponding clamping connection between the remaining (second) holding unit 110.2 of the holding device 110 and the optical element 109 is established in a second step of assembly, which follows this first step. The remaining (second) holding unit 110.2 may have a significantly lower stiffness in the direction of movement required for clamping purposes (i.e. in the radial direction R in the example of the invention) than the three (first) holding units 110.2, so as to be able to compensate for production inaccuracies without generating significant restoring forces and thus parasitic stresses.

[0154] In the example of the invention, the inner clamping element 110.16 of the respective holding unit 110.2 represents a holding interface unit within the meaning of the present disclosure for connecting the optical element 109. For each holding unit 110.2, relative to a respective one of the support interface units 110.3, a first stiffness S1 in a first direction perpendicular to the main extension plane of the optical element 109 (i.e. in the z-direction in the example of the invention) and a second stiffness S2 about an axis parallel to the radial direction R are defined for this holding interface unit 110.16.

[0155] The holding device 110, in particular the part thereof including the base unit 110.1, and in particular the supporting film element 110.4, is constructed by adapting the influencing parameters presented (in the content disclosed in the present invention) so that, for all supporting interface units 110.3 and for a (first) group of holding units 110.2 including at least 80%, preferably at least 90%, and more preferably 95% to 100% of the holding units 110.2, the variation of the first stiffness S1 between the holding units of this (first) group of holding units 110.2 is at most 900%, preferably at most 100%, and more preferably at most 10% to 1% of the minimum first stiffness S1 of the holding units 110.2 of this (first) group of holding units 110.2 (i.e. the minimum value of the first stiffness S1 exists among the holding units 110.2 of this (first) group of holding units 110.2). In this way, a particularly advantageous narrowband stiffness distribution is obtained in a first direction, ie perpendicular to the main extension plane of the optical element 109 .

[0156] It will be appreciated that such an adaptation of the stiffness distribution in the holding unit 110.2 may in principle be sufficient for a single degree of freedom, in particular any relevant degree of freedom, in particular the degree of freedom in which the main impact load is to be expected. Preferably, this adaptation is also carried out in further degrees of freedom. Likewise, it is naturally possible to carry out this adaptation only in one or more other degrees of freedom.

[0157] In the example of the invention, this adaptation is preferably also carried out with respect to the second stiffness S2. To this end, the holding device 110, in particular the part comprising the base unit 110.1, and in particular the supporting membrane element 110.4, is configured such that, for all supporting interface units 110.3 and for a further (second) group of holding units 110.2 comprising at least 80%, preferably at least 90%, more preferably 95% to 100% of the holding units 110.2 of this further (second) group of holding units 110.2, the second stiffness S2 varies between the holding units 110.2 of this further (second) group of holding units 110.2 by at most 900%, preferably at most 100%, more preferably at most 10% to 1% of the minimum second stiffness S2 of the holding units 110.2 of this further (second) group of holding units 110.2. It will be appreciated that the first and second groups of holding units 110.2 may be identical. However, they may also differ for one or more holding units 110 . 2 .

[0158] In principle, the optical element 109 can be manufactured from any suitable material in a single part or in a plurality of parts. Preferably, at least in the region of the protrusion 109.5, the optical element 109 is manufactured from a ceramic material, which in particular contains SiSiC, and / or the optical element 109 is manufactured from a material containing Zerodur, and / or from a lens material. In the variants described above with the interface element 109.6, this interface element can preferably be manufactured from a material containing Invar and / or stainless steel and / or molybdenum.

[0159] In principle, the holding device 110 may be constructed in any suitable manner from a plurality of separate parts in a so-called differential configuration. In the example of the invention, the base unit 110.1 is constructed in one piece with the supporting membrane element 110.4 and all holding units 110.2, thus resulting in a particularly robust and highly precisely manufactured design.

[0160] In principle, any suitable material can be used for the holding device 110 or its parts. This can be, for example, stainless steel, aluminum (Al), or beryllium (Be), individually or in any combination. Further suitable materials are aluminum alloys, in particular aluminum silicon (AlSi), beryllium alloys, in particular aluminum beryllium (AlBe), ceramic materials, in particular SiSiC, and glass fiber reinforced plastics (GFRP) or carbon fiber reinforced plastics (CFRP).

[0161] Using the design described above, it is possible to carry out the method according to the invention as described above.Therefore, in this respect, reference is made to the explanation given above in order to avoid repetition.

[0162] Second embodiment

[0163] The following references Figure 1, Figure 2 ,and Figures 5 to 7 A further preferred embodiment of an arrangement 208 according to the invention is described which can be used to replace the arrangement 108 in the imaging device 101. The arrangement 208 corresponds in its basic design and function to the arrangement 108 of FIG. Figures 2 to 4 108, and therefore only the differences will be discussed herein. In particular, equivalent components are provided with equivalent reference numerals, and similar components are provided with reference numerals that are incremented by 100. Unless otherwise stated below, reference is made to the above statements related to the first embodiment regarding the features, functions, and advantages of these components.

[0164] The difference in design with respect to the first embodiment lies essentially in the design of the base unit 210.1. In the example of the present invention, the supporting film element 210.4 is connected to a circumferential supporting ring structure 210.21 extending in the circumferential direction U on the rear side facing away from its front side (or the optical element 109). In the present specification, three supporting interface units 110.3 are again formed on the supporting ring structure 210.21. In the present specification, in some variations, a uniform distribution of the supporting interface units 110.3 can also be provided over the circumference of the base unit 210.1. However, in the example of the present invention, since the advantages of the design with the supporting film element 210.4 work particularly well here, the supporting interface units 110.3 are again distributed at irregular intervals along the circumferential direction.

[0165] In the example of the present invention, the supporting film element 210.4 is continuously connected to the supporting ring structure 210.21. Therefore, there is no gap (similar to the gap 110.12) between the supporting ring structure 210.21 and the supporting film element 210.4. However, it is understood that in other variations, this gap (similar to the gap 110.12) can also be provided at least partially as described above with the web element 110.11 of the first embodiment, so as to at least partially release the deformation ability of the supporting film element 210.4 in this area.

[0166] In the design of the exemplary embodiment of the present invention, the force flow between the support interface unit 110.3 and the individual holding units 210.2, and therefore the stiffness distribution within the holding units 210.2, can also be set by the design and / or orientation of the support ring structure 210.21. For this purpose, in the exemplary embodiment of the present invention, the respective distances of the support ring structure 210.21 and the inner section 210.5 (in particular the inner edge 210.22) of the support membrane element 210.4 vary along the circumferential direction U between the support interface units 110.3 that are immediately adjacent to each other in the circumferential direction.

[0167] In the present example, the support ring structure 210.21 connects the support interface units 110.3 that are immediately adjacent to each other in the circumferential direction, substantially along the shortest possible path without protruding inwardly beyond the inner edge 210.22 of the support membrane element 210.4 in the radial direction R. This allows a particularly advantageous force flow distribution.

[0168] It will be appreciated that the combination of a supporting film element 210.4 and a supporting ring structure 210.21 may in principle be sufficient for the holding device 210. However, in the example of the invention, the supporting ring structure is connected on the rear side facing away from the supporting film element 210.4 to a thin-walled reinforcing film element 210.23 extending mainly in the circumferential direction U and in the radial direction R. This can advantageously increase the stiffness of the holding device 210 as a whole, so that in particular an advantageously high resonance frequency of the holding device 210 occurs.

[0169] In the present specification, in principle, the reinforcing film element 210.23 can be designed in any suitable manner to obtain the desired reinforcing effect. In the example of the present invention, it has a structure substantially identical to that of the supporting film element. Therefore, the reinforcing film element 210.23 is also configured in the form of a thin-walled annular disc. Figure 5 The cross-sectional profile in the cross-sectional plane illustrated in extends substantially parallel to the radial direction R. With regard to the design and configuration of the reinforcing membrane element 210 . 23 , the explanations above with regard to the supporting membrane element 110 . 4 or 210 . 4 also apply in principle, so that reference is made in this respect.

[0170] In these designs, the holding unit 210.2 can in principle also be used for holding any suitable form of configuration of the optical element 109. In the example of the invention, the holding unit 210.2 is connected to the supporting film element 210.4 via a decoupling section 210.24. This makes it easy to ensure that the deformation capacity of the supporting film element 210.4 is limited by the rearward support ring structure 210.21 and compensated by the decoupling section 210.24. In the present specification, in principle, the decoupling via the decoupling section 210.24 can have any design and can be matched to the desired one or more degrees of freedom in which the decoupling is necessary. In the example of the invention, the decoupling section 210.24 is configured as a narrow web, so that the decoupling section 210.24 releases the degree of freedom of tilting around the tilting axis parallel to the radial direction R.

[0171] If possible from Figure 6 and Figure 7It can be seen that in particular the difference between the holding unit 210.2 and the holding unit of the first embodiment lies in the fact that the compliance of the holding element 210.2 in the radial direction R is caused by the inner clamping element 110.16 being held by the leaf spring element 210.18. The leaf spring element 210.18 is elongated along the circumferential direction U and extends (in the circumferential direction U) to both sides of the clamping element 110.16 in a plane perpendicular to the radial direction R. At its ends, the leaf spring element 210.18 is connected to the base body 210.25 of the holding unit 210.2. Again, the body 210.25 is connected to the supporting film element 210.4 via a decoupling section 210.24.

[0172] Due to this design of the holding unit 210.2, it is possible to obtain a configuration with small dimensions perpendicular to the main extension plane of the optical element 109. This makes it possible to save installation space in the direction perpendicular to the main extension plane of the optical element 109 (here the z direction) or to increase the dimensions of the support ring structure 210.21 in this direction, so that the rigidity of the base unit 210.1 can be significantly increased. This is advantageous from a dynamic point of view, especially with respect to the resonance frequency of the holding device 210.

[0173] This design also makes it possible to implement the method according to the invention described above in the same way, so that in this respect reference is made to the explanations given above.

[0174] In particular, it will be appreciated that the adaptation of the stiffness distribution in the holding unit 210.2 may be achieved to the same extent as has been described above for the first and second stiffness and / or for any other single or multiple degrees of freedom, in particular any relevant degrees of freedom, in particular the degrees of freedom in which the main impact load is to be expected. Furthermore, this may be achieved again via the holding device 210, in particular its part comprising the base unit 210.1, and in particular the supporting membrane element 210.4, in particular by adapting the influencing parameters as presented in the disclosure of the present invention.

[0175] The invention has been described above only based on examples from the field of microlithography. However, it is understood that the invention can also be used in the context of any other optical application, in particular imaging methods at different wavelengths, where similar problems arise with regard to the support of heavy optical units.

[0176] Furthermore, the invention can be used in combination with inspection of objects, for example so-called mask inspection, in which the integrity of masks used for microlithography is inspected, etc. Figure 1In the embodiment of the present invention, for example, a sensor unit which detects the imaging of the projected pattern of the mask 104.1 (for further processing) then replaces the substrate 105.1. This mask detection can then be carried out substantially at the same wavelength as used later in the microlithography process. However, it is also possible to use any desired wavelength deviating therefrom for the detection.

[0177] Finally, the invention has been described above based on specific embodiments showing specific combinations of features defined in the appended claims. It should be clearly pointed out at this point that the subject matter of the invention is not limited to these feature combinations, but all other feature combinations (as are evident from the appended patent claims) also belong to the subject matter of the invention.

Claims

1. An arrangement of a microlithography imaging device, comprising: A holding device (110; 210) for holding an optical element (109); in The optical element (109) comprises an optical surface (109.1) and defines a main extension plane, wherein the optical element (109) defines a radial direction and a circumferential direction; The holding device (110; 210) comprises a base unit (110.1; 210.1) and a plurality of separate holding units (110.2; 210.2); The base unit (110.1; 210.1) for connecting the holding device (110; 210) to the support structure (102.1) comprises a plurality of support interface units (110.3), the support interface units being spaced apart from each other in the circumferential direction; The holding units (110.2; 210.2) are connected to the base unit (110.1; 210.1) and are distributed along the circumferential direction and spaced apart from each other; and The holding unit (110.2; 210.2) is configured to hold the optical element (109) relative to the base unit (110.1; 210.1); Features The base unit comprises at least one supporting film element (110.4; 210.4), wherein The at least one supporting film element (110.4; 210.4) extends mainly along the circumferential direction and along the radial direction, wherein the at least one supporting film element (110.4; 210.4) has a thickness dimension transverse to the circumferential direction and the radial direction; and The holding unit (110.2; 210.2) is arranged on the front side of the at least one supporting film element (110.4; 210.4) facing the optical element (109).

2. The arrangement according to claim 1, wherein The microlithography imaging apparatus is used to use light in the extreme ultraviolet (EUV) range.

3. The arrangement according to claim 1, wherein The at least one supporting film element (110.4; 210.4) is configured in the form of a thin-walled annular disk or in the form of a thin-walled hollow conical frustum; and / or In a cross-sectional plane extending in the radial direction and perpendicular to the circumferential direction, the at least one supporting membrane element (110.4; 210.4) is inclined at most 10° relative to the radial direction; and / or The at least one supporting membrane element (110.4; 210.4) extends at least substantially parallel to the radial direction.

4. An arrangement according to any one of claims 1 to 3, wherein The at least one supporting membrane element (110.4; 210.4) has an inner section (110.5; 210.5) and an outer section (110.6) spaced apart from the inner section in the radial direction.

5. The arrangement according to claim 4, wherein The at least one supporting film element (110.4; 210.4) comprises an intermediate section (110.7) between the inner section (110.5; 210.5) and the outer section (110.6); and / or At least one of the holding units (110.2; 210.2) is connected to the at least one supporting film element (110.4; 210.4) between the inner section (110.5; 210.5) and the outer section (110.6) in the radial direction.

6. The arrangement of claim 4, wherein In the region of the outer section (110.6), the at least one supporting film element (110.4) is connected to a circumferential outer ring structure (110.8) extending in the circumferential direction, wherein the outer ring structure (110.8) is arranged at a rear side of the at least one supporting film element (110.4) facing away from a front side of the at least one supporting film element (110.4); and / or In the region of the inner section (110.5), the at least one supporting film element (110.4) is connected to a circumferential inner ring structure (110.9) extending in the circumferential direction, wherein the inner ring structure (110.9) is arranged at the rear side of the at least one supporting film element (110.4; 210.4) facing away from the front side of the at least one supporting film element (110.4; 210.4).

7. The arrangement of claim 6, wherein: At least some of the support interface units (110.3) are formed at the outer ring structure (110.8) or the inner ring structure, wherein the support interface units (110.3) are distributed at irregular intervals along the circumferential direction.

8. The arrangement of claim 6, wherein At least one web element (110.10) is provided interconnecting the outer ring structure (110.8) with the inner ring structure (110.9), wherein In the direction of the thickness dimension, a gap is formed between the at least one web element (110.10) and the at least one supporting membrane element (110.4; 210.4).

9. The arrangement of claim 8, wherein: The gap extends between the outer ring structure (110.8) and the inner ring structure (110.9) over at least 50% of the length of the web element (110.10).

10. The arrangement of claim 8, wherein At least one pair (110.11) of web elements (110.10) assigned to one another is provided, wherein the two web elements (110.10) of the at least one pair (110.11) engage the inner ring structure (110.9) immediately one after the other in the circumferential direction.

11. The arrangement of claim 10, wherein: The two web elements (110.10) of the at least one pair (110.11) are joined to the outer ring structure (110.8) immediately one after another in the circumferential direction; and / or The two web elements (110.10) of the at least one pair (110.11) are joined to the outer ring structure (110.8) between two supporting interface units (110.3) that are adjacent to each other in the circumferential direction; and / or Each of the two web elements (110.10) of the at least one pair (110.11) defines a longitudinal axis, and the two longitudinal axes, in a plan view of the main extension plane, extend at a mutual inclination of at most 10°; and / or Each of the two web elements (110.10) of the at least one pair (110.11) defines a longitudinal axis, and at least one of the two longitudinal axes, in a plan view of the main extension plane, extends with an inclination of at most 30° relative to a connecting line, wherein the connecting line connects two support interface units (110.3) that are adjacent to each other in the circumferential direction at the outer ring structure (110.8), and the corresponding web element (110.10) is joined between the two support interface units (110.3).

12. The arrangement of claim 4, wherein The at least one supporting film element (210.4) is connected at a rear side facing away from its front side to a circumferential supporting ring structure (210.21) extending in the circumferential direction; The support interface units (110.3) are formed at the support ring structure (210.21), wherein the support interface units (110.3) are distributed at irregular intervals along the circumferential direction.

13. The arrangement of claim 12, wherein: The distance between the support ring structure (210.21) and the inner section (210.5) or the inner edge (210.22) of the at least one support film element (110.4; 210.4) varies along the circumferential direction between at least two support interface units (110.3) that are adjacent to each other in the circumferential direction; and / or The support ring structure (210.21) protrudes inwardly substantially along the shortest path without exceeding the inner edge (210.22) of the at least one support film element (210.4) in the radial direction, and connects at least two support interface units (110.3) that are consecutive in the circumferential direction.

14. The arrangement of claim 12, wherein On the rear side facing away from the supporting film element (210.4), the supporting ring structure (210.21) is connected to at least one reinforcing film element (210.23) extending mainly in the circumferential direction and in the radial direction.

15. The arrangement of claim 14, wherein: The at least one reinforcing film element (210.23) is constructed in the form of a thin-walled annular disk or in the form of a thin-walled hollow conical frustum; and / or In a cross-sectional plane extending in the radial direction and perpendicular to the circumferential direction, the at least one reinforcing film element (210.23) extends at an inclination of at most 10° relative to the radial direction; and / or The at least one reinforcing membrane element (210.23) extends at least substantially parallel to the radial direction.

16. The arrangement of claim 12, wherein At least one of the two holding units (110.2; 210.2) positioned adjacent to each other in the circumferential direction is connected to the at least one supporting film element (210.4) via a decoupling section (210.24).

17. The arrangement of claim 16, wherein: The decoupling section (210.24) releases the degree of freedom of tilting about a tilting axis parallel to the radial direction.

18. An arrangement according to any one of claims 1 to 3, wherein In a cross-sectional plane perpendicular to the circumferential direction, a width dimension of the at least one supporting film element (110.4; 210.4) is defined, and a thickness dimension of the at least one supporting film element (110.4; 210.4) is 2% to 30% of the width dimension of the at least one supporting film element (110.4; 210.4); and / or The thickness dimension of the at least one supporting film element (110.4; 210.4) varies along the circumferential direction, wherein the thickness dimension varies depending on the angular distance to the nearest supporting interface unit (110.3) along the circumferential direction; wherein the thickness dimension increases as the angular distance to the nearest supporting interface unit (110.3) increases; and / or The thickness dimension of the at least one supporting film element (110.4; 210.4) varies along the radial direction, wherein the thickness dimension varies depending on a predetermined stiffness profile condition of the supporting film element in the radial direction; and / or The at least one supporting film element (110.4; 210.4) has at least one through hole (113) in at least one region positioned between two adjacent holding units (110.2; 210.2) in the circumferential direction.

19. The arrangement of claim 18, wherein: The at least one through hole (113) is in each region between two adjacent holding units (110.2; 210.2).

20. An arrangement according to any one of claims 1 to 3, wherein Each holding unit (110.2; 210.2) comprises a holding interface unit (110.16) for connecting the optical element (109); Relative to a corresponding one of the support interface units (110.3), each holding interface unit (110.16) for each holding unit (110.2; 210.2) defines a first stiffness in a first direction perpendicular to the main extension plane and a second stiffness about an axis parallel to the radial direction; The holding device (110; 210) is configured such that: for at least one supporting interface unit (110.3) and for a holding unit group that includes at least 80% of the holding unit (110.2; 210.2), the variation of the first stiffness among the holding units (110.2; 210.2) of the holding unit group is at most 900% of the minimum first stiffness of the holding units (110.2; 210.2) of the holding unit group.

21. The arrangement of claim 20, wherein: The holding device (110; 210) is configured such that: for at least one supporting interface unit (110.3) and for another holding unit group that includes at least 80% of the holding unit (110.2; 210.2), the variation of the second stiffness among the holding units (110.2; 210.2) of the other holding unit group is at most 900% of the minimum second stiffness of the holding units (110.2; 210.2) of the other holding unit group.

22. An arrangement according to any one of claims 1 to 3, wherein Each holding unit (110.2; 210.2) is designed to establish a clamping connection between the optical element (109) and the base unit (110.1; 210.1), which is separate from the other holding units (110.2; 210.2).

23. The arrangement of claim 22, wherein: At least one of the holding units (110.2; 210.2) comprises a holding interface unit for connecting to the optical element, wherein the holding interface unit comprises a first clamping element (110.15) and a second clamping element (110.16), the first clamping element (110.15) and the second clamping element (110.16) being supported against each other in order to establish the clamping connection, and the holding interface section (109.3) of the optical element (109) is clamped between the first clamping element (110.15) and the second clamping element (110.16).

24. An arrangement according to claim 23, wherein The first clamping element (110.15) and the second clamping element (110.16) are supported against one another by means of a tensioning element (111) for the purpose of producing the clamping connection.

25. The arrangement of claim 24, wherein: The tensioning element (111) protrudes with play through the recess (109.4) of the retaining interface section (109.3); and / or A compensating spring device (111.3) is provided which is configured to reduce tensioning force losses in the tensioning element (111).

26. An arrangement according to any one of claims 1 to 3, wherein Each holding unit (110.2; 210.2) comprises a holding interface unit (110.15, 110.16) for connecting to the optical element (109); and At least one of the retaining interface units (110.15, 110.16) is connected to the supporting film element (110.4; 210.4) via a connecting section (110.17, 110.18; 210.18).

27. An arrangement according to claim 26, wherein The connecting section (110.17, 110.18; 210.18) is constructed in such a way as to limit the rotational freedom about an axis extending substantially parallel to the radial direction; and / or The connecting section (110.17, 110.18; 210.18) is at least partially constructed in the manner of a leaf spring; and / or The connecting section (110.17, 110.18; 210.18) is configured to be compliant in the radial direction; and / or The connecting section (110.17, 110.18; 210.18) extends at least in sections substantially in a plane perpendicular to the radial direction; and / or The connecting section (110.17, 110.18; 210.18) defines a longitudinal axis, wherein the longitudinal axis of the connecting section (110.17, 110.18; 210.18) extends substantially perpendicular to the main extension plane or substantially parallel to the main extension plane.

28. An arrangement according to any one of claims 1 to 3, wherein At least one retaining interface section (109.3) of the optical element (109) is formed by a protrusion (109.5) of the optical element (109).

29. The arrangement of claim 28, wherein: A plurality of the retaining interface sections (109.3) are formed at a common protrusion (109.5) of the optical element (109); and / or All the holding interface sections (109.3) are formed at the annular protrusion (109.5) of the optical element (109); and / or The protrusion (109.5) of the optical element (109) extends in the circumferential direction and / or in a direction perpendicular to a plane defined by the circumferential direction and the radial direction.

30. An arrangement according to any one of claims 1 to 3, wherein At least one retaining interface section (109.3) of the optical element (109) is formed by a retaining interface element (109.6) connected to the optical element (109).

31. The arrangement of claim 30, wherein: The holding interface element (109.6) is inserted into the recess (109.8) of the optical element (109); and / or The retaining interface element (109.6) comprises a connecting sleeve having a convex ring (109.7).

32. The arrangement of claim 30, wherein At least in the region of the protrusion (109.5) of the optical element (109), the optical element (109) is made of a ceramic material, the ceramic material contains SiSiC, and / or the optical element (109) is made of a material containing Zerodur, and / or of a lens material; and / or The interface element (109.6) is made of a material containing Invar and / or stainless steel and / or molybdenum.

33. An arrangement according to any one of claims 1 to 3, wherein The optical surface (109.1) is a reflective optical surface, The optical surface (109.1) is arranged on a body (109.2) of the optical element (109); and The body (109.2) comprises at least one protrusion (109.5) on a side facing away from the optical surface (109.1), the protrusion forming an interface (109.3) with at least one of the holding units (110.2; 210.2).

34. An arrangement according to any one of claims 1 to 3, wherein The base unit (110.1; 210.1) has a ring-shaped configuration; and / or The base unit (110.1; 210.1) defines a main extension plane of the base unit (110.1; 210.1), and at least one of the holding units (110.2; 210.2) protrudes from the base unit (110.1; 210.1) in a manner substantially perpendicular to the main extension plane of the base unit (110.1; 210.1), wherein All holding units (110.2; 210.2) protrude from the base unit (110.1; 210.1) in a manner substantially perpendicular to a main extension plane of the base unit (110.1; 210.1); and / or The base unit (110.1; 210.1) has a single body configuration; and / or The supporting film element (110.4; 210.4) is formed as a single body with at least one of the holding units (110.2; 210.2).

35. An arrangement according to any one of claims 1 to 3, wherein Providing at least 6 holding units (110.2; 210.2); and / or The holding units (110.2; 210.2) are arranged in a substantially uniform distribution along the circumferential direction.

36. An arrangement of a microlithography imaging apparatus, comprising: A holding device (110; 210) for holding an optical element (109); in The optical element (109) comprises an optical surface (109.1) and defines a main extension plane, wherein the optical element (109) defines a radial direction and a circumferential direction; The holding device (110; 210) comprises a base unit (110.1; 210.1) and a plurality of separate holding units (110.2; 210.2); The base unit (110.1; 210.1) for connecting the holding device (110; 210) to the support structure (102.1) comprises a plurality of support interface units (110.3) which are spaced apart from each other in the circumferential direction; The holding units (110.2; 210.2) are connected to the base unit (110.1; 210.1) and are arranged in a manner distributed along the circumferential direction and spaced apart from each other; and The holding unit (110.2; 210.2) is configured to hold the optical element (109) relative to the base unit (110.1; 210.1); Each holding unit (110.2; 210.2) comprises a holding interface unit (110.16) for connecting to the optical element (109); Relative to a corresponding one of the support interface units (110.3), each holding interface unit (110.16) for each holding unit (110.2; 210.2) defines a first stiffness in a first direction perpendicular to the main extension plane; Features The base unit (110.1; 210.1) comprises at least one supporting film element (110.4; 210.4), wherein The holding unit (110.2; 210.2) is arranged on the front side of the at least one supporting film element (110.4; 210.4) facing the optical element (109); and At least a portion of the holding device (110; 210) comprising the at least one supporting film element (110.4; 210.4) is constructed so that: for at least one supporting interface unit (110.3) and for a holding unit group that includes at least 80% of the holding units (110.2; 210.2), the variation of the first stiffness among the holding units (110.2; 210.2) of the holding unit group is at most 900% of the minimum first stiffness of the holding units (110.2; 210.2) of the holding unit group.

37. An arrangement according to claim 36, wherein The imaging device is used to use light in the extreme ultraviolet (EUV) range.

38. The arrangement of claim 36, wherein Relative to a corresponding one of the support interface units (110.3), each holding interface unit (110.16) for each holding unit (110.2; 210.2) defines a second stiffness about an axis parallel to the radial direction; and The portion of the holding device (110; 210) comprising the at least one supporting film element (110.4; 210.4) is constructed so that: for at least one supporting interface unit (110.3) and for at least 80% of the holding units (110.2; 210.2) of the other holding unit group, the variation of the second stiffness among the holding units (110.2; 210.2) is at most 900% of the minimum second stiffness of the holding units (110.2; 210.2) of the other holding unit group.

39. An arrangement according to any one of claims 36 to 38, wherein The at least one supporting film element (110.4; 210.4) extends mainly along the circumferential direction and along the radial direction, wherein the at least one supporting film element (110.4; 210.4) has a thickness dimension transverse to the circumferential direction and the radial direction; and / or The at least one supporting film element (110.4; 210.4) is configured in the form of a thin-walled annular disk or in the form of a thin-walled hollow conical frustum; and / or In a cross-sectional plane extending in the radial direction and perpendicular to the circumferential direction, the at least one supporting membrane element (110.4; 210.4) is inclined at most 10° relative to the radial direction; and / or The at least one supporting membrane element (110.4; 210.4) extends at least substantially parallel to the radial direction.

40. An arrangement according to any one of claims 36 to 38, wherein The at least one supporting membrane element (110.4; 210.4) has an inner section (110.5; 210.5) and is spaced apart from an outer section (110.6) in the radial direction.

41. The arrangement of claim 40, wherein: The at least one supporting membrane element (110.4; 210.4) has an intermediate section (110.7) between the inner section (110.5; 210.5) and the outer section (110.6); and / or At least one of the holding units (110.2; 210.2) is connected to the at least one supporting film element (110.4; 210.4) between the inner section (110.5; 210.5) and the outer section (110.6) in the radial direction.

42. The arrangement of claim 40, wherein In the region of the outer section (110.6), the at least one supporting film element (110.4) is connected to a circumferential outer ring structure (110.8) extending in the circumferential direction, wherein the outer ring structure (110.8) is arranged at a rear side of the at least one supporting film element (110.4) facing away from a front side of the at least one supporting film element (110.4); and / or In the area of ​​the inner section (110.5), the at least one supporting film element (110.4) is connected to a circumferential inner ring structure (110.9) extending in the circumferential direction, wherein the inner ring structure (110.9) is arranged at the rear side of the at least one supporting film element (110.4; 210.4) facing away from the front side of the at least one supporting film element (110.4; 210.4).

43. An arrangement according to claim 42, wherein At least some of the support interface units (110.3) are formed at the outer ring structure (110.8) or the inner ring structure, wherein the support interface units (110.3) are distributed at irregular intervals along the circumferential direction.

44. The arrangement of claim 42, wherein At least one web element (110.10) is provided interconnecting the outer ring structure (110.8) with the inner ring structure (110.9), wherein In the direction of the thickness dimension of the at least one supporting film element transverse to the circumferential direction and the radial direction, a gap is formed between the at least one web element (110.10) and the at least one supporting film element (110.4; 210.4).

45. An arrangement according to claim 44, wherein The gap extends between the outer ring structure (110.8) and the inner ring structure (110.9) over at least 50% of the length of the web element (110.10).

46. ​​The arrangement of claim 44, wherein At least one pair (110.11) of web elements (110.10) assigned to one another is provided, wherein the two web elements (110.10) of the at least one pair (110.11) engage the inner ring structure (110.9) immediately one after the other in the circumferential direction.

47. The arrangement of claim 46, wherein: The two web elements (110.10) of the at least one pair (110.11) are joined to the outer ring structure (110.8) immediately one after another in the circumferential direction; and / or The two web elements (110.10) of the at least one pair (110.11) are joined to the outer ring structure (110.8) between two supporting interface units (110.3) that are adjacent to each other in the circumferential direction; and / or Each of the two web elements (110.10) of the at least one pair (110.11) defines a longitudinal axis, and the two longitudinal axes, in a plan view of the main extension plane, extend at a mutual inclination of at most 10°; and / or Each of the two web elements (110.10) of the at least one pair (110.11) defines a longitudinal axis, and at least one of the two longitudinal axes, in a plan view of the main extension plane, extends with an inclination of at most 30° relative to a connecting line, wherein the connecting line connects two support interface units (110.3) that are adjacent to each other in the circumferential direction at the outer ring structure (110.8), and the corresponding web element (110.10) is joined between the two support interface units (110.3).

48. The arrangement of claim 40, wherein The at least one supporting film element (210.4) is connected at a rear side facing away from its front side to a circumferential supporting ring structure (210.21) extending in the circumferential direction; The support interface units (110.3) are formed at the support ring structure (210.21), wherein the support interface units (110.3) are distributed at irregular intervals along the circumferential direction.

49. The arrangement of claim 48, wherein The distance between the support ring structure (210.21) and the inner section (210.5) of the at least one support membrane element (110.4; 210.4) varies along the circumferential direction between at least two support interface units (110.3) that are adjacent to each other in the circumferential direction; and / or The support ring structure (210.21) protrudes inwardly substantially along the shortest path without exceeding the inner edge (210.22) of the at least one support film element (210.4) in the radial direction, and connects at least two support interface units (110.3) that are consecutive in the circumferential direction.

50. The arrangement of claim 48, wherein On the rear side facing away from the supporting film element (210.4), the supporting ring structure (210.21) is connected to at least one reinforcing film element (210.23) extending mainly in the circumferential direction and in the radial direction.

51. The arrangement of claim 50, wherein: The at least one reinforcing film element (210.23) is configured in the form of a thin-walled annular disk or in the form of a thin-walled hollow conical frustum; and / or In a cross-sectional plane extending in the radial direction and perpendicular to the circumferential direction, the at least one reinforcing film element (210.23) extends at an inclination of at most 10° relative to the radial direction; and / or The at least one reinforcing membrane element (210.23) extends at least substantially parallel to the radial direction.

52. The arrangement of claim 48, wherein At least one of the two holding units (110.2; 210.2) positioned adjacent to each other in the circumferential direction is connected to the at least one supporting film element (210.4) via a decoupling section (210.24).

53. The arrangement of claim 52, wherein: The decoupling section (210.24) releases the degree of freedom of tilting about a tilting axis parallel to the radial direction.

54. An arrangement according to any one of claims 36 to 38, wherein In a cross-sectional plane perpendicular to the circumferential direction, a width dimension of the at least one supporting film element (110.4; 210.4) is defined, and a thickness dimension of the at least one supporting film element (110.4; 210.4) is 2% to 30% of the width dimension of the at least one supporting film element (110.4; 210.4); and / or The thickness dimension of the at least one supporting film element (110.4; 210.4) varies along the circumferential direction, wherein the thickness dimension varies depending on the angular distance to the nearest supporting interface unit (110.3) along the circumferential direction; wherein the thickness dimension increases as the angular distance to the nearest supporting interface unit (110.3) increases; and / or The thickness dimension of the at least one supporting film element (110.4; 210.4) varies along the radial direction, wherein the thickness dimension varies depending on a predetermined stiffness profile condition of the supporting film element in the radial direction; and / or The at least one supporting film element (110.4; 210.4) has at least one through hole (113) in at least one region positioned between two adjacent holding units (110.2; 210.2) in the circumferential direction.

55. The arrangement of claim 54, wherein: The at least one through hole (113) is in each region between two adjacent holding units (110.2; 210.2).

56. An arrangement according to any one of claims 36 to 38, wherein Each holding unit (110.2; 210.2) is designed to establish a clamping connection between the optical element (109) and the base unit (110.1; 210.1), which is separate from the other holding units (110.2; 210.2).

57. The arrangement of claim 56, wherein: At least one of the holding units (110.2; 210.2) comprises a holding interface unit for connecting to the optical element, wherein the holding interface unit comprises a first clamping element (110.15) and a second clamping element (110.16), the first clamping element (110.15) and the second clamping element (110.16) being supported against each other in order to establish the clamping connection, and the holding interface section (109.3) of the optical element (109) is clamped between the first clamping element (110.15) and the second clamping element (110.16).

58. The arrangement of claim 57, wherein The first clamping element (110.15) and the second clamping element (110.16) are supported against one another by means of a tensioning element (111) for the purpose of producing the clamping connection.

59. The arrangement of claim 58, wherein The tensioning element (111) protrudes with play through the recess (109.4) of the retaining interface section (109.3); and / or A compensating spring device (111.3) is provided which is configured to reduce tensioning force losses in the tensioning element (111).

60. An arrangement according to any one of claims 36 to 38, wherein Each holding unit (110.2; 210.2) comprises a holding interface unit (110.15, 110.16) for connecting to the optical element (109); and At least one of the retaining interface units (110.15, 110.16) is connected to the supporting film element (110.4; 210.4) via a connecting section (110.17, 110.18; 210.18).

61. The arrangement of claim 60, wherein: The connecting section (110.17, 110.18; 210.18) is configured such that it limits the rotational freedom about an axis extending substantially parallel to the radial direction; and / or The connecting section (110.17, 110.18; 210.18) is configured at least in sections in the manner of a leaf spring; and / or The connecting section (110.17, 110.18; 210.18) is configured to be compliant in the radial direction; and / or The connecting section (110.17, 110.18; 210.18) extends at least in sections substantially in a plane perpendicular to the radial direction; and / or The connecting section (110.17, 110.18; 210.18) defines a longitudinal axis, wherein the longitudinal axis of the connecting section (110.17, 110.18; 210.18) extends substantially perpendicular to the main extension plane or substantially parallel to the main extension plane.

62. An arrangement according to any one of claims 36 to 38, wherein At least one retaining interface section (109.3) of the optical element (109) is formed by a protrusion (109.5) of the optical element (109).

63. The arrangement of claim 62, wherein: A plurality of the retaining interface sections (109.3) are formed at a common protrusion (109.5) of the optical element (109); and / or All the holding interface sections (109.3) are formed at the annular protrusion (109.5) of the optical element (109); and / or The protrusion (109.5) of the optical element (109) extends in the circumferential direction and / or in a direction perpendicular to a plane defined by the circumferential direction and the radial direction.

64. An arrangement according to any one of claims 36 to 38, wherein At least one retaining interface section (109.3) of the optical element (109) is formed by a retaining interface element (109.6) connected to the optical element (109).

65. The arrangement of claim 64, wherein: The holding interface element (109.6) is inserted into the recess (109.8) of the optical element (109); and / or The retaining interface element (109.6) comprises a connecting sleeve having a convex ring (109.7).

66. The arrangement of claim 64, wherein At least in the region of the protrusion (109.5) of the optical element (109), the optical element (109) is made of a ceramic material, the ceramic material contains SiSiC, and / or the optical element (109) is made of a material containing Zerodur, and / or of a lens material; and / or The interface element (109.6) is made of a material containing Invar and / or stainless steel and / or molybdenum.

67. An arrangement according to any one of claims 36 to 38, wherein The optical surface (109.1) is a reflective optical surface; The optical surface (109.1) is arranged on a body (109.2) of the optical element (109); and The body (109.2) comprises at least one protrusion (109.5) on a side facing away from the optical surface (109.1), the protrusion forming an interface (109.3) with at least one of the holding units (110.2; 210.2).

68. An arrangement according to any one of claims 36 to 38, wherein The base unit (110.1; 210.1) has a ring-shaped configuration; and / or The base unit (110.1; 210.1) defines a main extension plane of the base unit (110.1; 210.1), and at least one of the holding units (110.2; 210.2) protrudes from the base unit (110.1; 210.1) in a manner substantially perpendicular to the main extension plane of the base unit (110.1; 210.1), wherein All holding units (110.2; 210.2) protrude from the base unit (110.1; 210.1) in a manner substantially perpendicular to a main extension plane of the base unit (110.1; 210.1); and / or The base unit (110.1; 210.1) has a single-body configuration; and / or The supporting film element (110.4; 210.4) is formed as a single body with at least one of the holding units (110.2; 210.2).

69. An arrangement according to any one of claims 36 to 38, wherein Providing at least 6 holding units (110.2; 210.2); and / or The holding units (110.2; 210.2) are arranged in a substantially uniform distribution along the circumferential direction.

70. An optical imaging device comprising The lighting device (102) comprises a first optical element group (106); An object device (104) for storing an object (104.1); The projection device (103) comprises a second optical element group (107); and An imaging device (105), wherein The lighting device (102) is configured to illuminate the object (104.1); and The projection device (103) is configured to project the image of the object (104.1) onto the image device (105); Features The lighting device (102) and / or the projection device (103) comprises at least one arrangement (108) according to any one of claims 1 to 69.

71. The optical imaging device according to claim 70, wherein: The optical imaging device is a microlithography optical imaging device.

72. A method for supporting a microlithographic optical element (109), wherein An optical element (109) comprising an optical surface and defining a main extension plane is held by a holding device (110; 210), wherein the optical element (109) defines a radial direction and a circumferential direction; in The optical element (109) is held by a plurality of separate holding units (110.2; 210.2) of the holding device (110; 210) relative to a base unit (110.1; 210.1) of the holding device (110; 210), wherein the holding units are arranged in a manner distributed along the circumferential direction and spaced apart from each other; The base unit (110.1; 210.1) is connected to the support structure via a plurality of support interface units (110.3) spaced apart from each other in the circumferential direction; Features At least one supporting film element (110.4; 210.4) of the base unit extends mainly along the circumferential direction and along the radial direction, wherein the at least one supporting film element (110.4; 210.4) has a thickness dimension transverse to the circumferential direction and the radial direction; and The holding unit (110.2; 210.2) is arranged on the front side of the at least one supporting film element (110.4; 210.4) facing the optical element (109).

73. The method of claim 72, wherein: The microlithography optics (109) are used to use light in the extreme ultraviolet (EUV) range.

74. The method of claim 72, wherein The corresponding connections between the three holding units (110.2; 210.2) of the holding device (110; 210) and the optical element (109) are each established in a first step so that: the optical element (109) is fixed in space relative to the base unit (110.1; 210.1); The respective connections between the remaining holding units (110.2; 210.2) of the holding device (110; 210) and the optical element (109) are each established in a second step, which follows the first step.

75. A method for supporting a microlithographic optical element (109), wherein An optical element (109) comprising an optical surface and defining a main extension plane is held by a holding device (110; 210), wherein the optical element (109) defines a radial direction and a circumferential direction; in The optical element (109) is held by a plurality of separate holding units (110.2; 210.2) of the holding device (110; 210) relative to a base unit (110.1; 210.1) of the holding device (110; 210), wherein the holding units are arranged in a manner distributed along the circumferential direction and spaced apart from each other; The base unit (110.1; 210.1) is connected to the support structure via a plurality of support interface units (110.3) spaced apart from each other in the circumferential direction; Each holding unit (110.2; 210.2) comprises a holding interface unit (110.16) connected to the optical element (109); Relative to a corresponding one of the support interface units (110.3), each holding interface unit (110.16) for each holding unit (110.2; 210.2) defines a first stiffness in a first direction perpendicular to the main extension plane; Features The holding unit (110.2; 210.2) is arranged on at least one supporting film element (110.4; 210.4) of the base unit (110.1; 210.1); and At least a portion of the holding device (110; 210) comprising the at least one supporting film element (110.4; 210.4) is constructed so that: for at least one supporting interface unit (110.3) and for a holding unit group that includes at least 80% of the holding units (110.2; 210.2), the variation of the first stiffness among the holding units (110.2; 210.2) of the holding unit group is at most 900% of the minimum first stiffness of the holding units (110.2; 210.2) of the holding unit group.

76. The method of claim 75, wherein: The microlithography optics (109) are used to use light in the extreme ultraviolet (EUV) range.

77. The method of claim 75, wherein The corresponding connections between the three holding units (110.2; 210.2) of the holding device (110; 210) and the optical element (109) are each established in a first step so that: the optical element (109) is fixed in space relative to the base unit (110.1; 210.1); The respective connections between the remaining holding units (110.2; 210.2) of the holding device (110; 210) and the optical element (109) are each established in a second step, which follows the first step.

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