EP4031937A1

EP4031937A1 - Multi-faceted mirror for illumination optics of a projection printing system

Info

Publication number: EP4031937A1
Application number: EP20775847.5A
Authority: EP
Inventors: Willi Anderl; Christian Körner; Hubert Holderer; Markus Holz; Manuel Stompe; Stefan Seitz
Original assignee: Carl Zeiss SMT GmbH
Current assignee: Carl Zeiss SMT GmbH
Priority date: 2019-09-19
Filing date: 2020-09-18
Publication date: 2022-07-27
Also published as: DE102019214269A1; US11789367B2; US20220206398A1; CN114730136A; WO2021053164A1; KR20220066313A; JP2022548962A

Abstract

A multi-faceted mirror for the illumination optics of a projection printing system has a plurality of displaceable individual facets (8i) having a main facet body (35) and a reflection surface (36) provided thereon, wherein at least one subgroup of the individual facets (8i) has a displacement region, such that, in one or more displacement positions, the subgroup comes into contact with an abutment surface (38).

Description

Facet mirror for an illumination optics of a projection exposure system

The present patent application takes priority of the German patent application DE 10 2019214269.9, the content of which is incorporated herein by reference.

The invention relates to a facet mirror for an illumination optics of a projection exposure system. The invention further relates to a single facet for a facet mirror of an illumination optics of a projection exposure system. The invention also relates to lighting optics, a lighting system, an optical system and a projection exposure system with a corresponding facet mirror. Finally, the invention relates to a method for producing a micro- or nanostructured component and a component produced according to the method.

Facet mirrors for lighting optics of Projektionsbe lighting systems with a large number of displaceable individual facets are known from the prior art. Here, the individual facets are designed in such a way that they do not interfere with one another in the event of a controlled displacement. The facets are designed in particular in such a way that they do not touch one another when they are displaced.

A mechanism is known from the prior art in order to protect the facets of the facet mirror, in particular when it is being transported, against undesired movements. However, the mechanism does not protect the facets during normal operation of the facet mirror.

It is an object of the present invention to improve a facet mirror for a lighting optics of a projection exposure system.

This object is achieved by the features of claim 1.

The essence of the invention is to design the individual facets of the facet mirror in such a way that they touch a stop surface in one or more displacement positions. The individual facets of the facet mirror can in particular be designed in such a way that they touch a stop surface in reversibly adjustable displacement positions. Such a reversibly adjustable displacement position is also called an active or actuatable displacement position designated. The individual facets can in particular have one or more discrete active displacement positions. They can also be designed such that they only touch a stop surface in the event of an undesired deflection, in particular in the event of a parasitic movement, in particular in the event of a transport and / or earthquake. Such a deflection is also referred to as a passive displacement position. In case of doubt, the shift position is understood to mean both the actively possible and the passively possible shift positions.

The facets touch the stop surface with their base body or a stop element arranged on or in this. The reflection surfaces of the individual facets preferably remain in contact with each other.

The stop surface is in particular a defined, in particular a specific stop surface. The stop surface is in particular a stop surface for the mutual stop of two adjacent facets. The stop surface is in particular spaced apart from the reflection surface of the respective individual facet. The stop surface and the reflection surface of an individual facet form, in particular, disjoint areas.

The stop surface is in particular formed in or on the facet base body. The stop surface can in particular be designed or arranged in or on the facet base body in such a way that, when projected in the direction of a surface normal to the reflection surface of the individual facet, in particular in the case of a projection in the direction of a surface normal through the centroid of the reflection surface of the individual facet, it forms an outer edge of the Forms projection of the facet base body or protrudes over such in at least one direction perpendicular to the surface normal.

The projection is in particular a parallel projection, in particular an orthogonal projection.

The projection is, in particular, a projection into a projection plane which, in particular, is perpendicular to the surface normal. According to the invention, it was recognized that this can prevent the facets from hitting one another in an uncontrolled manner. An uncontrolled clash is understood here to mean a clash of the facets in an uncontrolled, in particular an undesired area. In particular, it is possible to prevent the reflection surfaces of the individual facets from hitting one another. This can prevent damage to the reflective surfaces.

The individual facets can in particular be designed in such a way that they only touch a stop surface in actuatable, adjustable displacement positions. In particular, the prerequisite for touching the stop surface is not an undesirable or unforeseeable external effect on the individual facets.

The individual facets can also be designed in such a way that they touch the stop surface in the event of an undesired or unpredictable external influence, in particular exclusively in the case of an undesired or unpredictable external influence.

According to one aspect of the invention, at least a subset of the individual facets, in particular all of the individual facets, can have displacement areas such that adjacent individual facets touch one another in one or more displacement positions. The individual facets can touch each other, especially in passive displacement positions.

In a basic or neutral position, the individual facets are preferably arranged without contact, in particular at a distance from one another. In particular, they can be in at least one active displacement position, in particular in all active displacement positions, in relation to all stop surfaces.

In general, the idea according to the invention relates to an optical module with a plurality of displaceable optical elements.

According to one aspect of the invention, adjacent individual facets in a basic or neutral position are each spaced apart from one another by a gap. A corresponding gap can also be in predetermined switching positions, in particular in any desired switching position to be available. In particular, the reflection surfaces of the individual facets are preferably arranged at a distance from one another in the basic or neutral position.

In the basic or neutral position, the individual facets are in particular also spaced apart from all stop surfaces by a gap.

The gaps are sufficiently large to enable the individual facets to be shifted in the shifting area. On the other hand, the gaps are as narrow as possible in order to enable the individual facets to be packed tightly. The width of the gaps between adjacent individual facets can in particular be less than 1 mm, in particular less than 0.5 mm. The width of the column is in particular no more than 50%, in particular no more than 30%, in particular no more than 20%, in particular no more than 15%, in particular no more than 10%, in particular no more than 5%, in particular no more than 3%, in particular no more than 2%, in particular no more than 1% of the He stretching the individual facets, in particular their base bodies or their reflective surfaces, in the corresponding direction.

The area within which the facet can be actuated displaceably is referred to as the displacement area of an individual facet. This area is also known as the active relocation area. In addition, it can be possible that the individual facets are displaced by external influences, for example vibrations, in particular when the facetted mirror is being transported. The area possible here is called the passive displacement area. In particular, it can be larger than the active displacement range. Unless otherwise stated, the displacement area of a facet is understood to mean the largest displacement area in each case, in particular the larger of the active and passive displacement area in each case.

According to one aspect of the invention, the total area of the gaps between adjacent individual facets is at most, in particular, at most 50%, in particular at most 30%, in particular at most 20%, in particular at most 15%, in particular at most 10%, in particular at most 5%, in particular at most 3%, in particular at most 2%, in particular at most 1% of the total area of the facet mirror or the sum of the reflection surfaces of all the individual facets of the facet mirror. The individual facets in particular have one, two or more degrees of freedom of displacement. In particular, they have two degrees of freedom of tilting. In particular, they can be tilted around two, in particular special, tilting axes that run perpendicular to one another. They can also be linearly displaceable in the direction parallel to a surface normal, in particular in a central point of the reflection surface.

The individual facets, in particular their facet base bodies, can each be formed monolithically.

The component of an individual facet on which the reflective surface is applied is referred to here as the facet base body. The facet base body has, in particular, a cross section which essentially corresponds to the reflection surface. The cross section of the facet base body deviates in particular by a maximum of 30%, in particular a maximum of 20%, in particular a maximum of 10% from the dimensions of the reflective surface of the respective facet.

The facet base body points in particular in a projection, in particular in a parallel projection, in particular in an orthogonal projection, in the direction of a surface normal to the reflection surface, in particular in the area of one of the stop surfaces and / or in the area of one of the stop elements in the direction perpendicular to a surface normal on the reflection surface of the respective individual facet has a cross section which deviates by at most 30%, in particular at most 20%, in particular at most 10% from the dimensions of the reflective surface of the respective facet. This can in particular be a square, in particular special elongated cross-section. The cross section can have straight or curved Beran applications. The aspect ratio of this cross section of the basic facet body corresponds, in particular within the specified maximum deviations, to that of the reflection surface of the respective individual facet. In this regard, reference is made to the following description.

The individual facets can also have further components, for example elements of an actuator device for displacing the respective facet and / or elements for supporting the facet. Corresponding elements, the cross-section of which is clear, in particular by at least deviates from the reflective surface by at least 50%, are not regarded as part of the faceted base body.

The individual facets, in particular their reflective surfaces, are preferably elongated. They preferably have an aspect ratio (greatest extent in the longitudinal direction: greatest extent perpendicular thereto, that is to say in the transverse direction) of at least 3: 1, in particular at least at least

5: 1, in particular at least 8: 1, in particular at least 10: 1, in particular at least 12: 1. The aspect ratio is preferably at most 100: 1, in particular at most 50: 1, in particular at most 30: 1, in particular at most 20: 1.

According to a further aspect of the invention, the stop surface, which is touched by a single facet in a certain displacement position, is formed by another single facet, in particular its base body, in particular a predetermined area of the base body, or by a separate stop element.

The facet mirror can in particular be designed in such a way that contact between two adjacent individual facets is only possible when non-actuatable degrees of freedom are excited. Such a deflection of the individual facets can occur, for example, in the event of an earthquake or transport load.

The contact with the separate stop element can also be limited to a stimulation of non-actuatable degrees of freedom, in particular in the event of an earthquake or transport load.

According to a further aspect of the invention, the facet base body of the individual facets is designed in such a way that adjacent individual facets touch each other in certain deflection or displacement positions in a predetermined area of the facet base body.

In particular, it is possible to determine in advance on the basis of the intended displacement range of the individual facets and the geometric configuration of the basic facet body, in which area of the same can come into contact with an adjacent individual facet. This makes it possible to specifically adapt this area to a possible collision.

The area of the facet base body in which contact can occur is preferably at a distance from the reflection surface of the respective individual facets, in particular from their edges. This reduces the risk of damage to the reflection surface, in particular its edges, due to a collision of adjacent individual facets. This also applies in particular to unplanned, in particular unpredictable, collisions such as those that can occur, for example, when transporting the facet mirror and / or in the event of an earthquake.

The predetermined area of the facet base body forms, in particular, the stop surface.

According to a further aspect of the invention, the facet base bodies are designed in such a way that a distance between the facet base bodies of two adjacent individual facets is less than a distance between their reflection surfaces.

This property is particularly true in the basic position of the individual facets. It is preferably generally applicable regardless of the displacement positions of the individual facets. A corresponding design of the facet base body is described in more detail below.

According to a further aspect of the invention, one or more stop elements are provided on or in the facet base body.

The stop elements serve as a buffer. In a sense, they serve as bumpers. They enable a targeted specification of the areas in which adjacent individual facets can touch, in particular they enable the targeted specification of the stop surfaces.

The stop elements can be designed as separate elements and each connected to the faceted base body. You can in particular be positively connected to the faceted base body. According to one aspect of the invention, the stop elements are connected to the facet base body by gluing, soldering, welding, screwing, clipping, shrinking or plugging. In principle, all conceivable connection techniques for connecting the attachment elements to the facet base bodies are possible.

The stop elements can in particular be exchangeable. The stop elements can also be designed in one piece with the facet base bodies. This enables a particularly simple and stable production. The stop elements are preferably arranged at predetermined positions, in particular in the region of vertices, corners, edges or other predetermined positions of the facet base body.

The stop elements can extend over the entire width and / or over the entire length of the facet base body. In particular, they can extend over the entire circumference of the facet base body. As an alternative to this, it is possible to provide a plurality of stop elements, each of which has a smaller extension. This can save weight. This has a positive effect on the mechanical properties of the individual facets.

In particular, provision can be made for one or more stop elements to be arranged at the end of the facet base body, in particular in the region of its ends in the longitudinal direction. It is also possible to arrange one or more stop elements in a central area, in particular in a central area with regard to the longitudinal direction, on the facet base body. This can be particularly advantageous in the case of curved facets.

The stop elements can in particular be provided in the areas in which collisions are most likely to occur. They can in particular be arranged in the areas in which the distance between the respective facet base body and an adjacent facet base body is minimal. This information can relate to the position of the facet base bodies in a neutral, that is to say undeflected basic state and / or to a displacement position of adjacent facet base bodies in which their spacing is minimal. The stop elements can be formed from the same material as the facet base body. In particular, they can be formed from copper or a copper alloy. They can also be made or consist of other materials. Other materials that can be used for the stop elements are, for example, Zerodur, ULE, aluminum, ceramic, quartz, silicon.

The stop elements can be provided with a coating, in particular a wear-resistant coating. In this way, particle abrasion can be reduced, in particular prevented.

According to a further aspect of the invention, the stop elements are laterally over the Re flexionsfläche. In particular, they protrude laterally over the reflection surface when viewed from above. In particular, they protrude laterally over the reflection surface in the transverse direction.

The stop elements in particular have an extension in the direction parallel to the reflection surface, which is greater than the extension of the reflection surface in this direction. The stop elements in particular have an extension in the direction parallel to the width of the reflection surface, which is greater than the width of the reflection surface.

In this way, damage to the reflective surface in the event of a collision can be effectively and reliably prevented.

According to a further aspect of the invention, the stop elements protrude over the facet base body in the opposite direction to the surface normal of the reflection surface. In particular, they protrude above the facet base on the side of the facet base opposite the reflective surface.

The stop elements can also have an extension in the direction parallel to a surface normal paint of the reflection surface, which is smaller than the extension of the facet base body in this direction. According to a further aspect of the invention, all of the individual facets of the facet mirror each have identical stop elements and / or stop elements at essentially identical positions.

This facilitates the production of the individual facets and the programming of the facet contours.

Alternatively, different individual facets can have different stop elements and / or stop elements at different positions. In particular, it is possible to individually provide each of the individual facets with one or more stop elements. This allows for greater flexibility in planning the facets.

The equality and / or the differences of the stop elements can relate to their shape and / or their arrangement on the respective individual facets.

According to a further aspect of the invention, the stop elements have an extension which extends over the entire length of an individual facet. The stop elements can in particular extend over the entire circumference of an individual facet.

This protects the individual facet in a particularly reliable manner.

According to a further aspect of the invention, the individual facets, in particular their base bodies, have means for weight reduction and / or a weight-reduced design.

In particular, bores, recesses, pockets, thinnings or bevels can serve as means for reducing weight.

According to a further aspect of the invention, the facet mirror has one or more means for limiting the displacement range of the individual facets. The facet mirror can in particular have one or more means for limiting undesired deflection, in particular for limiting parasitic movements of the individual facets. In this case, the means for limiting the displacement range, in particular the means for limiting the undesired parasitic movements of the individual facets, can form the stop surface.

The means for limiting the displacement range of the individual facets can be formed out as pins, wel che are in particular also referred to as snubbers, forks, pockets or U-profiles.

The game of the respective stop surfaces is preferably smaller than the facet gap to be adjacent individual facets.

According to a further aspect of the invention, the free end of the means for limiting the displacement area of an individual facet is arranged in the area of the axis of rotation. As a result, the play of the individual facets around the means for limiting the displacement range of the same can be reduced. In particular, this does not reduce the available play of the individual facets as a result of their acutation about the axis of rotation.

In order to reduce the play even further, it can be provided that the means or means for limiting the displacement range of the individual facets are adjusted.

Provision can in particular be made to measure the gaps between the individual facets and / or to determine special spacers and to arrange them on the facets and / or to make the stops adjustable or adjustable.

Another object of the invention is to improve individual facets for a facet mirror of an illumination optics of a projection exposure system, in particular in accordance with the preceding description.

This object is achieved by individual facets with a facet base body and a reflective surface arranged thereon and one or more stop elements seen on or in the facet base body. The advantages result from those already described.

According to one aspect, one or more stop surfaces and / or stop elements are provided on or in the facet base body which, when projected in the direction of a surface normal onto the reflection surface, protrude beyond the reflection surface in at least one direction perpendicular to this surface normal.

The surface normal is in particular the surface normal through the centroid of the reflection surface.

According to one aspect, the individual facets have one or more stop surfaces and / or stop elements which, when projected in the direction of a surface normal onto the reflection surface, protrude both in at least one direction perpendicular to this surface normal and in an opposite direction over the reflection surface.

According to one aspect, the individual facets have one or more stop surfaces and / or stop elements which, when projected in the direction of a surface normal onto the reflection surface, protrude beyond the reflection surface over the entire circumference of the reflection surface.

The stop elements can be a special design of the Facettengrundkör pers, in particular a thickening of the same. The base body is preferably wider, at least in some areas, than the reflection surface of the individual facet.

The stop elements can also be separate components which are connected to the facet base body.

The reflection surfaces of the individual facets can be planar. They can also have a positive or negative refractive power. They can also be designed toric.

The reflection surfaces of the individual facets can in particular be rectangular, trapezoidal or curved, in particular in the shape of a circular ring. According to a further aspect of the invention, the facet base body has at least one free end, in particular two free ends, and is designed in such a way that its cross section decreases towards the free end or towards the free ends.

The cross section of the facet base body is reduced in particular at least partially starting from a fastening area towards the free end or ends.

The cross section can in particular continuously, in particular monotonically, decrease towards the free end. This allows the mass moment of inertia to be reduced. The cross section of the facet base body can also contribute to increasing the rigidity of the facet base body.

The cross section can also increase again on the very outside, in the area of the free end. In the area of the free end, the facet base body can in particular have a stop element.

According to a further aspect of the invention, the facet base body has means for reducing its mass moment of inertia and / or means for increasing its rigidity.

Recesses, bores or, in general, a weight-reduced design of the facet base can serve as a means for reducing the mass moment of inertia of the facet base.

As a means of increasing the rigidity of the facet base body, a profiled training can serve from the same. The facet base body can in particular have at least partially a T-shaped, a U-shaped or an H-shaped cross section. The Fa cettengrundkörper can also be manufactured additively. In particular, it can have hollow structures. This allows the mass moment of inertia of the facet base body to be reduced particularly effectively.

Further objects of the invention are to provide an illumination optics for a projection exposure system, an illumination system for a projection exposure system, an optical one Improve system for a projection exposure system and a projection exposure system.

These objects are achieved by an illumination optics, an illumination system, an optical system and a projection exposure system with a facet mirror according to the previous description.

The designs according to the invention offer in particular improved protection, in particular the optical surfaces, during transport and in the event of an earthquake load.

The advantages result from those of the facet mirror.

Further objects of the invention consist in improving a method for producing a micro- or nanostructured component and a correspondingly produced component.

These tasks are achieved by providing a projection exposure apparatus in accordance with the preceding description.

The advantages result in turn from those of the facet mirror, to which reference is made.

Further advantages and details of the invention emerge from the description of Ausfüh approximately examples based on the figures. Show it:

Fig. 1 schematically shows the components and the beam path of a Projektionsbe lighting system,

2 schematically shows an exemplary arrangement of field facets on a field facet mirror,

3 and 4 schematically an actuator device for shifting a field facet about two independent tilting axes, 5 schematically shows a further detail to illustrate the relative position of the tilt axis of a field facet relative to its reflection surface,

6 shows schematically and by way of example the collision of two adjacent facets during a rotation about an axis parallel to their surface normals,

7 shows an example of a perspective view of an individual facet,

8 shows an example of a cross section of a stop element for protecting a facet,

9 shows an example of a side view through a facet according to FIG. 7 with two stop elements arranged at the end,

Fig. 10 schematically shows a representation according to FIG. 6, wherein the facets are protected by stop elements,

11 to 13 are schematic representations to illustrate different tilting situations of two adjacent facets,

14 and 15 schematically two different arrangements of stop elements on facets,

16 shows an example of a perspective view of a structure-optimized facet,

17 schematically shows a perspective partial view of a facet, the base body of which has means for reducing the mass moment of inertia and means for increasing the rigidity,

18 schematically shows a perspective view of a facet with a balancing element, 19 shows an exemplary detailed view of the arrangement of an exemplary stop element on the base body of a facet,

20 to 22 exemplarily different configurations of the edge of a stop element,

23 schematically shows a view of a facet with a separate stop element for limiting the displacement range of the same,

24 schematically shows a cross section through adjacent facets with anchoring elements according to FIG. 23,

25 schematically shows a longitudinal section through a facet to illustrate a preferred arrangement of the stop element according to FIG. 23 relative to a tilt axis of the facet and

26 schematically and by way of example a variant in which the stop element is designed as a separate, lateral stop,

27 shows, by way of example, a further cross section of a stop element for

Protection of a facet and

28 shows an example of a perspective view of a facet with three attachment elements.

In the following, the general structure and will first be described with reference to FIG

Beam path in a projection exposure system 1 is described.

The projection exposure system 1 includes an illumination optics la for illuminating an object field 2 in an object plane 3 with illuminating radiation 4. The projection exposure system 1 also includes a projection optics lb for imaging one not shown in FIG shown, arranged in the area of the object plane 3 with structures to be imaged on a wafer, also not shown in FIG. 1, which is arranged in an image plane 31. Many details are known from the prior art.

The illuminating radiation 4 can in particular be EU V radiation, in particular illuminating radiation with a wavelength of at most 30 nm, in particular 13.5 nm or less.

The illuminating radiation 4 is generated by a radiation source 5. A plasma source or a free electrode laser (FEL) can serve as the radiation source 5. For details, reference is again made to the prior art.

The combination of the lighting optics la and the radiation source 5 is also referred to as a lighting system lc.

The illumination radiation 4 emitted by the radiation source 5 is collected by a collector 6. The collector 6 reflects the illumination radiation 4 and leads it to the subsequent components of the illumination optics la.

In the beam path after the collector 6, the illuminating radiation 4 strikes a first optical element in the form of a first facet mirror 7, which is also referred to as a field facet mirror. The first facet mirror 7 is used to generate secondary light sources in the lighting system lc.

A total reflection surface of the first facet mirror 7 acted upon by the illumination radiation 4 is subdivided into a plurality of first facets 8i, which are also referred to as field facets. In Figures 1 and 2, four first facets 8i to 8 ₄ are shown schematically.

Partial bundles 12i of illuminating radiation 4, in particular the partial bundles _{12i to 12 4} of illuminating _{radiation 4 assigned to the four illustrated first facets 8 1} to 8 ₄ , are also shown schematically and by way of example in FIG. The first facets are usually elongated. You can be formed from rectangular. They can also be curved, in particular configured in the shape of a circular ring segment.

The first facets can all have identical dimensions. It is also possible to design the first facet mirror 7 with first facets of different dimensions.

The first facets can in particular have an aspect ratio of at least 5: 1, in particular at least 8: 1, in particular at least 12: 1, in particular at least 13: 1. The aspect ratio of the first facets is in particular at most 100: 1, in particular at most 50: 1.

The shape of the first facets can in particular be adapted to the shape of the object field 2. In particular, it can be geometrically similar to the shape of the object field 2. The shape of the first facets is in particular such that the illumination radiation 4 reflected by them illuminates the object field 2 or certain subregions thereof as precisely as possible when the projection exposure system 1 is in operation.

Each of the first facets can be displaced, in particular tilted, in order to set different lighting settings. The first facets can in particular be tilted about two axes perpendicular to one another.

In the following, a Cartesian (x, y, z) coordinate system is used to describe positional relationships. In this coordinate system, the first facets can each be tilted about a tilt axis running in the x direction and about a tilt axis running in the y direction. The z-axis is in particular parallel or almost parallel to a surface normal of the respective facet.

In order to move the first facets, actuators are provided, of which an actuator 16 is indicated in FIG. 1 as a representative. The actuator 16 is connected to a central control device 19 via a control line 18. About corresponding, in the figure 1, the control device 19 is connected to all other actuators assigned to the first facets.

For further details of the first facets, reference is made to US 2003/0086524 A1, in particular Figures 7 to 14, to which reference is made in full.

At the location of the secondary light sources generated by the first facet mirror, that is, in an image plane to the radiation source 5, a second optical element in the form of a second facet mirror 20 is arranged. The second facet mirror 20 is also referred to as a pupil facet mirror. The illuminating radiation 4 is applied to the pupil facet mirror via the first facet mirror 7.

The surface of the second facet mirror 20 that can be acted upon is subdivided into a plurality of second facets 2L, of which four second facets 2h to 2h are shown in FIG. 1 by way of example. The second facets 2h to 2h are each assigned to one of the first facets 8 to 11, so that a secondary light source is generated at the location of the respectively acted upon second facets 2h to 2h.

As indicated schematically in FIG. 1, the second facets can also be tiltable by actuators. An actuator 25 assigned to the second facet 21 is shown as an example of this in FIG. The actuator 25 is in signal connection with the control device 19 via a beam line 18.

In the beam path after the second facet mirror 20, transmission optics 27 with wide ren mirrors 28, 29 are arranged. Here, the mirror 28 can be hit by the illuminating radiation 4 with a small angle of incidence, for example an angle of incidence of less than 30 °. The mirror 29 can be acted upon in grazing incidence, for example with an incidence angle of more than 60 °.

The preceding description of the projection exposure system 1 is to be understood as an example. Other embodiments of the lighting system lc, as they are known from the prior art, are also possible. Further details of the facets are described below. Even if the following de description and the figures relate to facets of the first facet mirror 7, the aspects described are equally possible and advantageous for the facets of the second facet mirror 20.

In FIG. 2, the top view of a section of the surface of the first facet mirror 7 is shown as an example.

As is shown by way of example in FIG. 2, many facets 8i are arranged next to one another on the facet mirror 7. Here, adjacent facets 8i, 8i + i are each separated from one another by a gap 32. In the variant shown in FIG. 2, the gaps 32 run parallel to the x or y direction.

In order to keep reflection losses as low as possible, the gaps 32 are as narrow as possible. The gap width is in particular at most 1 mm. The gap width is in particular no more than 50%, in particular no more than 30%, in particular no more than 20%, in particular no more than 15%, in particular no more than 10%, in particular no more than 5%, in particular no more than 3%, in particular no more than 2%, in particular no more than 1% of the extension of the facets 8i in the corresponding direction.

Overall, preferably a maximum of 50%, in particular a maximum of 30%, in particular a maximum of 20%, in particular a maximum of 15%, in particular a maximum of 10%, in particular a maximum of 5%, in particular a maximum of 3%, in particular a maximum of 2%, in particular a maximum of 1% of the total area of the first facet mirror 7 covered by columns 32. The illuminating radiation 4 cannot be reflected at the gaps 32. Column 32 thus lead to transmission losses.

On the other hand, the gaps 32 are necessary in order to enable a certain actuation range of the facets 8i. In FIGS. 3 and 4, details of the actuators 16 for displacing the facets 8i are shown by way of example and schematically. The actuation takes place via a lever 33. This can be done by magnetic forces. The magnet is located in particular on the underside of the lever 33. Below this, energized coils are provided, which can lead to a deflection of the lever 33 and thus to a tilting of the facet 8i. The actuator 16 can also have one or more restoring elements, for example in the form of leaf springs 34.

The facets 8i each have a facet base 35 and a reflection surface 36. The reflective surface 36 has edges 40 on the edge.

The facets 8i can be attached to a common frame or a common plate. It is also possible to fix the facets 8i in groups on modular plates.

The reflection surface 36, which is also generally referred to as an optical surface, can be designed to be flat. However, it can also be curved. In particular, it can have a particularly concave or convex design. It can also be toroidal or have any other shape.

As is shown by way of example in FIG. 5, the tilt axes 37 can lie in the region of the reflection surface 36 (FIG. 5, left). The tilt axis 37 can also lie below, that is to say behind the reflection surface 36 (FIG. 5, center). The tilt axis 37 can also lie above, that is to say in front of the reflection surface 36 (FIG. 5, right). The position of the tilt axis 37 relative to the reflective surface 36 has an influence on the required width of the gap 32 in order to ensure that adjacent facets 8i, 8i + i are free from collisions over a specified tilt angle range (tilt range).

The facet base body 35 can preferably, at least in sections, have a cross-section that decreases in the direction perpendicular to the reflection surface 36, for example a trapezoidal cross-section. A side angle b can in particular be as large as the maximum tilt angle to be set. It can also be bigger. The dimensions of the facet base body 35, in particular its mass moment of inertia, can be reduced by a larger side angle b, in particular a stronger bevel, of the facet base body 35. Depending on the fastening method, the individual facets 8i can have a low natural frequency that is excited, for example, during transport or in the event of unexpected vibrations, for example during an earthquake. This can lead to collisions between adjacent facets 8i, 8i _{+ i} .

FIG. 6 shows an example of a collision of two adjacent facets when they rotate about their z-axis, which runs parallel to a surface normal on a central point of the reflection surface 36. Such a collision can lead to indentations on the optical edges, that is to say in the edge region of the reflection surface 36.

While the facets 8i, 8i _{+ i} control can be tilted about the x- and y-axes, rotation about the z-axis is undesirable during normal operation of the projection exposure system 1. Such a rotation around the z-axis can, however, be stimulated in the event of a transport or earthquake. This can lead to damage to the facets 8i, 8i _{+ i} , which should preferably be avoided.

Different concepts are known from the prior art in order to avoid, in particular to prevent _{, a collision of adjacent facets 8i, 8i + i.} Such concepts are usually complex. It has also been found that their effectiveness is often insufficient.

According to the invention, these problems are solved by allowing a controlled collision of the optical component, in particular the facets 8i. According to the invention, it is provided here that the facet base body 35 and the reflection surface 36 are each designed in such a way that the reflection surface 36 is not damaged in the event of a collision. This can in particular be achieved in that the facet base body 35 is provided with defined stop surfaces which are spaced from the reflection surface 36 of the respective facet 8i and in the area of which contact can occur. As will be described in more detail below, separate stop elements, to which the facet base body 35 can strike, can also serve as stop surfaces. The stop surface can in particular be formed by a predetermined area of an adjacent facet or by an additional mechanical component.

The distance of the facet base body from the respective associated stop surface is in particular special smaller than the width of the gap 32 in the corresponding direction. The distance between the facet base body 35 and the associated stop surface is in particular smaller than the distance between the reflection surface 36 and the stop surface or the reflection surface 36 of the adjacent facet. This ensures that, in the event of a collision, it is not the optical edges, that is to say the edges of the reflective surface 36, but the desired stop areas that collide.

In FIG. 7, a perspective view of a facet 8i is shown as an example.

In the variant shown in FIG. 7, anchoring elements 38 are provided at the end of the facet base body 35. A side view through the facet according to FIG. 7 is shown by way of example in FIG.

A cross section of the stop element 38 is shown in detail in FIG. The stop element 38 has, in particular, stop edges 39. The stop edges 39 are ver in the direction perpendicular to the tilt axis 37 to the edges 40 of the reflective surface 36 to the outside.

FIG. 27 shows a cross section of a variant of the stop element 38. The stop element 38 according to FIG. 27 has a shoulder 48 on both sides of the reflective surface 36. The shoulder 48 extends in particular in a direction parallel to a width of the facet. It leads to improved protection of the reflective surface 36, in particular its edges 40.

Intermediate stages between the formation of the stop element 38 according to FIG. 27 and the embodiment according to FIG. 8 are also possible. The shoulder 48 can in particular be oriented at an angle c in the range from 90 ° to 150 °, in particular in the range from 90 ° to 135 °, preferably of at least 100 °, to a vertical direction 49. The vertical direction 49 runs in particular parallel to a surface normal 50 through a central point 51 of the reflection surface 36.

The stop edge 39 can be rounded or chamfered.

As is shown by way of example in FIG. 9, the stop elements 38 project downwards, that is to say on the side of the facet base body 35 facing away from the reflection surface 36, beyond the facet base body 35. The vertical protrusion can be determined on the basis of the desired tilting range of the facets 8i. The tilting range of the facets 8i can, for example, be up to 100 mrad.

The stop elements 38 can be plate-shaped. They can also be designed so that they can be pushed onto the facet base body 35 in the manner of a sleeve.

The stop elements 38 can each end on the free ends of the Facettengrundkör pers 35 be arranged in the longitudinal direction.

You can also vice ben the free end of the facet base body 35 on three sides in the longitudinal direction. A corresponding design is shown as an example in FIG. Such a design of the stop elements 38 protects the facets 8i, 8i _{+ i} , in particular their reflective surfaces 36, in particular also in the event of a collision due to a rotation about the z-axis.

The stop elements 38 are preferably designed and / or arranged on the basic facet body 36 such that in any tilt position, in particular in any operating switch position, any, in particular unexpected, stimuli of the facets 8i, for example also around the z- Axis, at most leads to collisions in the area of the stop elements 38, but not in the area of the edges 40 of the reflective surface 36.

As is shown by way of example in FIG. 28, stop elements 38 can also be arranged in a central region on the facet base body 35. This can be advantageous in particular in the case of arcuate facets 8i. The stop elements 38 are preferably arranged in the area or areas in which the distance between the respective facet base body 35 and the adjacent facet base body 35 or the adjacent stop element 38 is the smallest. The stop elements 38 are arranged in particular in the areas of the facet base body 35 in which collisions are most likely to occur.

As is shown by way of example in FIG. 28, the stop elements 38 arranged in the region of the free ends of the facet base body 35 do not need to be arranged completely at the end of the facet base body 35 either.

As is shown by way of example in FIG. 28, different stop elements 38 can have different geometrical designs. In particular, it is possible to design the stop elements 38 arranged in the central region of the facet base body 35 differently than the stop elements 38 arranged further at the end. It is particularly possible to design the stop elements 38 arranged in a central region on the facet base body 35 in such a way that they extend in the perpendicular direction have to the reflection surface 36, which is less than the extension of the facet base body 35 in this direction.

In particular, the stop elements 38 arranged in the central areas of the facet base body 35 can be configured as thickened portions of the facet base body 35.

The stop elements 38 arranged in the central regions of the facet base body 35 can only be arranged on a single side of the facet base body 35. It is also possible to arrange corresponding stop elements 38 on two sides, that is to say on opposite sides of the facet base body 35.

An arrangement of the stop elements 38 in the areas in which the width of the gap 32 is particularly small, in particular minimal, makes it possible to make the stop elements 38 particularly thin and thus particularly light. The stop elements 38 are designed in particular in such a way that when the facets 8i are displaced and / or due to unexpected stimuli of the facets 8i, contact with a stop surface can occur, the facets 8i being the stop surface in a predetermined area which is affected by the reflection surface 36 is spaced, touch.

In FIGS. 11 to 13, different constellations are shown by way of example when adjacent facets 8i, 8i _{+ i} are tilted.

If the facets 8i, 8i _{+ i} are tilted away from one another (FIG. 11), the adjacent edges 40 are not endangered or at least less endangered.

In the opposite case, that is, when the adjacent facets 8i, 8i _{+ i} are tilted towards one another, collisions can in principle occur. According to the invention, however, it is provided that the stop elements 38 are designed in such a way that the stop edge 39 of one stop element 38 comes into contact with the other stop element 38. In principle, the stop element 38, in particular its stop edge 39, can also come into contact with another area of the facet base body 35 of the adjacent facet 8i.

However, it should be ensured that the area in which contact (collision) of a facet 8i can occur is at a distance from the reflection surface 36 of the respective facet 8i.

From the geometrical conditions it can easily be deduced that the protrusion e, by which the stop edge 39 protrudes laterally over the reflective surface 36, has at least a ratio to the height h of the reflective surface 36 above the plane through the stop edges 39 in the illustrated embodiment of the stop element 38 must be as large as the tangent of the triple side angle b: e: h> tan (3b). With a side angle b of 40 mrad, the following applies in particular: e: h> 120 pm / mm. With such a design of the stop elements 38, the edges 40 of the reflective surface 36 are protected against collisions for all possible tilting positions of the facets 8i. As illustrated by way of example in FIG. 13, this also applies to the case of additional actuation about the second tilt axis. In the present case, this primarily leads to a relative displacement of the two facets 8i, 8i + i in the z-direction. This can lead to the other facet 8i then being endangered. However, in the illustrated embodiment of the stop elements 38, this is also protected by the stop elements, in particular in such a way that the edges 40 of their reflective surface 36 cannot collide.

As can also be seen by way of example from FIG. 13, the extent of the stop elements 38 in the z-direction is dependent on the maximum tilting range about the y-axis. A sufficient extension of the stop elements 38 in the z-direction can ensure that the stop elements 38 provide a stop surface regardless of the tilt position about the y-axis in order to protect the edges 40 of the reflective surface 36 against collisions.

For a preferred value of the projection e of the stop edges 39 over the reflective surface 36, in particular in the direction parallel to the reflective surface 36 or perpendicular to the respective tilt axis, the following factors can preferably be taken into account:

Manufacturing tolerances in the manufacture of the facet base body 35 are usually in the range from 10 μm to 50 μm.

The stop elements 35 can wear out over the service life of the facets 8i. In the event of a collision, there may be a maximum indentation of the stop edge 39 in the range of at most a few pm. This depends, among other things, on the material of the stop elements 38 and / or on the angle of incidence in the event of a collision. As will be described in more detail below, provision can be made for the stop edges 39 to be rounded. This can reduce the Hertzian pressure in the event of a collision.

The protrusion e is particularly dependent on the displacement range (actuation range) of the facets 8i. In addition, the absolute value of the protrusion e is dependent on the distance between the stop edge 39 and the edge 40 of the reflective surface 36 to be protected, in particular on the height h. The smaller this distance or the height h, the smaller the over stand e can be selected. A protrusion e in the range from 20 gm to 100 gm has been found to be particularly useful.

In order to keep the distance between adjacent reflective surfaces 36 as small as possible, a smaller protrusion e is advantageous. Preferably, the distance between adjacent facet base bodies 35 in a neutral position of the facets 8i, 8i + i, in particular a distance between the adjacent stop edges 39 of adjacent facets 8i, 8i + i <100 gm, in particular at most 50 gm. These specifications preferably apply for the distance between two adjacent reflection surfaces 36, in particular in the neutral position of the facets 8i, 8i + i, or in particular in a position of the same in which their surface normals run parallel to one another.

Another aspect of the invention is described below with reference to FIGS. 14 and 15.

This aspect relates to the arrangement of the stop elements 38 on the facet base body 35. According to the invention, it was recognized that the narrow point, that is, the point of the smallest distance between the two adjacent facets 8i, 8i + i, is not always in the area of their free ends. It can also be the case that the nominal width of the gap 32 between adjacent facets 8i, 8i + i varies over the length of the facets 8i, 8i + i.

According to the invention it can therefore be provided to arrange stop elements 38 on the facet base body 35 depending on the position of the narrow point. The stop elements 38 can in particular not only be arranged at the end of the facet base body 35. This is shown by way of example in FIG. 14 for the facets 8i, 8 ₂ . The stop elements 38 can, however, also be arranged centrally on the facet base body 35. This is shown by way of example in FIG. 14 for the facets 82, 83.

Alternatively, the dimension of the protrusion e can be chosen differently. This is shown as an example in FIG. Here the protrusion e of the stop elements 38 between tween the facets 8 ₂ and 8 ₃ is chosen greater than the amount of the protrusion e between the facets th 8i and 8 ₂ . This also makes it possible to take into account the small gap width in the central area of the facets 8 ₂ , 8 _3.

In other words, it is possible to flexibly select the position of the arrangement of the stop elements 38 as required. As an alternative to this, it is possible to arrange the stop elements 38 in each case at a predetermined position of the facet base body 35. In this case in particular, the dimension of the protrusion e can be flexibly adapted to the gap width.

A predetermined position of the arrangement of the stop elements 38 on the facet base body 35, which is the same for all facets 8i, has the advantage that the variety of facet features is reduced. This makes programming the facet contours easier.

According to a further variant, provision is made for the stop edge 39 to be formed over the entire length of the facets 8i. The stop edge 39 can in particular be formed over the entire circumferential area of the facet base body 35. The stop edge 39 can here be formed continuously. It can also be designed to be interrupted. This can save weight.

In particular for reasons of weight saving, it can be advantageous to arrange stop elements 38 only in the critical areas on the facet base body 35. In particular in the case of a relatively large tilting range, for example a tilting range of more than 40 mrad, it can be advantageous to arrange stop elements 38 exclusively in the region of the free ends of the facets 8i.

The stop elements 38 can in particular only be arranged at discrete locations in the longitudinal direction of the facet base body 35. In particular, a maximum of 10, in particular a maximum of 8, in particular a maximum of 6, in particular a maximum of 4, in particular 2 attachment elements 38 can be arranged on the facet base bodies 35. The stop elements 38 can each have an extension in the longitudinal direction of the facet base 35 which is at most 10%, in particular at most 5%, in particular at most 3%, in particular at most 2% of the length of the facet base 35. Overall, the stop elements 38 can be designed and arranged on the facet base body 35 in such a way that the mass moment of inertia of the facet base body 35 is increased by a maximum of 10%, in particular a maximum of 5%, in particular a maximum of 3% due to the arrangement of the stop elements 38.

Another aspect of the invention relates to an advantageous embodiment of the facet base body 35. It was recognized that a facet that is as lightly weighted as possible is advantageous for dynamic reasons. On the one hand, this keeps the amplitudes low in the event of an excitation, and on the other hand, the collision energy is reduced in the event of collisions. Even if, according to the invention, contact between a facet 8i and a stop surface is permitted, care must be taken that such collisions do not lead to negative consequences, in particular do not lead to damage to the facet 8i or to particle formation.

Ehn forming the facets 8i with the lowest possible weight, in particular with the lowest possible mass moment of inertia, in particular with regard to the dynamically critical axes, in particular the tilting axes, the facet base bodies 35 can be designed in a structure-optimized manner.

The facet base body 35 can in particular have means for reducing the weight, in particular special means for reducing the mass moment of inertia. As a means for reducing the weight of the facet base body 35 and for reducing its mass moment of inertia, it can be provided, for example, to design the facet base body 35 with a cross-section that reduces towards the free end. In particular, it is possible to reduce the height of the facet base body 35 towards the end of the facet. A corresponding design is shown as an example in FIG. The angle of incidence w between the inner side of the facet base body 35 and the front side thereof is in particular in the range from 2 ° to 10 °, in particular in the range from 4 ° to 6 °. As a result of the thinner design of the facet base body 35 at its ends, its mass moment of inertia can be reduced by approximately 10% compared to a design that is not optimized for the structure. At the same time, the rigidity of the facet base body 35 can be increased. The rigidity of the facet base body 35 can in particular be increased in that the cross-sectional area increases towards the support point of the facet. The total mass of the facet base body 35 increases, but that From the moment of inertia, as the cross-section is reduced towards the free end. Thus, in total over the entire length of the facet base body 35, the mass moment of inertia is reduced and the rigidity is increased. For example, by reducing the cross-sectional area of the facet base body 35 towards its ends, the sagging due to the inherent weight of the facet base body 35 can be improved by a factor of more than two, in particular more than three. This information relates, for example, to a facet with a length of 120 mm, a width of 6.6 mm and an average height of 14 mm.

In addition, the necessary rigidity can be shifted towards the actuator axis.

A further means for reducing the weight, in particular for reducing the mass moment of inertia of the facet base body 35, is shown as an example in FIG. According to this variant, 35 bores are provided in the facet base body. The holes also lead to weight savings. As an alternative or in addition to this, pockets can also be provided, in particular from the underside of the facet base body 35 or from the side surfaces of the same. In addition, tapering of the cross section is also possible in other ways, for example by means of bevels on the sides.

Another means for optimizing the facet base body 35 is shown in FIG. According to this variant, the facet base body 35 is mounted in a strongly asymmetrical manner. A balancing element 41 is provided in the area of the shorter free end.

By means of the means described above, the mass moments of inertia of the facet base body 35, in particular by Rx, can be reduced by up to 30%.

The stop elements 38 preferably have a small extent in the x direction, that is to say in the longitudinal direction of the facet base body 35. The stop elements 38 can in particular have an extension in the range from 1 mm to 3 mm in the x direction. For example, the previously exemplarily described facets 8i, in particular together with the other moving masses of the manipulator, have a total _{moment of inertia I yy} of approximately 180,000 g · mm ² . The additional total moment of inertia I _yy due to the stop elements 38 is less than 5000 m · mm ² , that is to say less than 3% of the total moment of inertia

Iyy.

According to a further variant, provision can be made for the weight and thus the moment of inertia additionally caused by the stop element 38 to be further reduced by means of recesses, for example bores or pockets. Such weight savings can be introduced into the stop element 38 in particular at the end face in the x direction. As a result, the relative proportion of the mass moment of inertia of the stop elements 38 in the total moment of inertia I _{yy of} the facets 8i can be reduced to less than 2%.

The stop elements 38 serve in particular to protect the facets 8i, in particular to protect their reflective surfaces 36, in the event of unexpected stimuli and / or vibrations. They protect the facets in particular against seismic load cases in which the excited oscillation amplitudes can be a multiple of the width of the intended column 32.

Further aspects of the invention are described below.

The stop elements 38 can be designed as separate components. In particular, they can be placed on the facet base body 35. They are generally connected to the facet base body 35. Essentially all conceivable connection techniques are possible here. The stop elements 38 can in particular be glued, soldered, welded, screwed, clipped or shrunk onto or slipped onto the facet base body 35.

The formation of the stop elements 38 as separate components has the advantage that the stop elements 38 can be made from a different material than the facet base body 35. They can also be made from the same material. They can in particular be made of copper or a copper alloy. This is particularly advantageous with regard to particle formation. In addition, the use of copper or a copper alloy to produce the stop elements 38 has the advantage that due to the relatively low hardness of copper results in a slight indentation in a non-disruptive point in the event of a collision. The formation of particles is largely prevented.

It is also possible to monolithically integrate the stop element into the facet base body 35. In particular, they can be designed in one piece with the facet base body 35. In this case, the stop elements 38 can be formed in particular by the geometric details, in particular the shape of the facet base body 35. This enables a particularly simple and robust production.

As shown by way of example in FIGS. 20 to 22, the design of the stop elements 38, in particular their stop edge 39, can be sharp-edged (FIG. 20), not sharp-edged, in particular tapering flat (FIG. 21) or rounded (FIG. 22). A rounded, preferably chamfered training makes it possible to reduce the Hertzian pressure. It is a preferred embodiment.

Collision tests have shown that after several hundred collisions with typical impact energy, only very little wear and tear, in particular an indentation in the contact area of no more than 2 pm, could be determined.

According to a further variant, the height h by which the reflection surface 36 is offset in the direction of its surface normal relative to a plane through the stop edges 39 of the stop element 38 can also approach zero. This corresponds to the case that the used optical surface of the facets 8 i does not extend to their geometric edge, in particular not to the edge of the facet base body 35. Such a design also means that, in the event of a collision, the reflective surfaces 36 do not collide with one another. However, in this case the reflection surfaces 36 are surrounded by an edge region which is not used to reflect the illumination radiation 4. This reduces the degree of filling of the facet mirror 7 and thus the degree of efficiency with regard to transmission is reduced.

A further exemplary embodiment is described below with reference to FIGS. 23 to 25. For general details, reference is made to the previous embodiments. In this exemplary embodiment, the stop surface is formed by a means for limiting the displacement range of the facets 8i. According to the variant shown in the figures, a pin 42, which is also referred to as a snubber, serves as such a means. The pin 42 dips into a pocket 43 on the underside of the facet base body 35. The immersion depth is large enough to cover the entire tilting area. In principle, the pin 42 can also be tilted together with the facet base body 35.

The pin 42 and a bearing 46 of the facet 8 i, which is only shown in FIG. 23, are arranged on a common base plate 47.

The precise positioning of the pin 42, in particular of the free end of the same which plunges into the pocket 43, can advantageously be adjustable.

The play between the pin 42 and a stop side 44 on the inside of the pocket 43 is smaller than the distance between two adjacent facets 8i, 8i _{+ i} , in particular smaller than the width of the gap 32 between two adjacent facets 8i, 8i _{+ i} . The play between the pin 42 and the stop side 44 is in particular smaller than the part of the gap 32 available for the TO tolerances. This ensures that the protective effect for the edges 40 of the reflective surface 36 is also guaranteed in this variant.

In order to reduce the play around the pin 42, it is advantageous to form and / or arrange the pin 42 in such a way that its free end runs in the area of the tilt axis 37 (the x-axis in the illustrated case).

In order to reduce the play even further, the pin 42 can be adjusted. The pin 42 can in particular be designed to be adjustable.

The pin 24 can be designed in particular spherical at its free end. This prevents the tilting of the facets from being hindered In the exemplary embodiments shown, the snubber is shown as a pin 42. It is also conceivable to design the snubber as a fork, that is to say with several free ends which grip around the facets. According to a further variant shown by way of example in FIG. 25, a lateral stop 45 is provided instead of the pin 42.

It should be noted in general that the facets 8i, in particular their facet base bodies 35, have a displacement area such that they touch a stop surface in certain displacement positions. The shift positions can be reversibly actuatable shift positions. It can also involve undesired deflection positions which can occur in the event of transport or in the event of an earthquake, in particular exclusively in the event of transport or earthquake, but not in the case of controlled relocation. The stop surface can in this case be formed by a surface on a further optical element, in particular a further facet base body 35 or a stop element 38 arranged thereon. It can also be formed by a separate mechanical detail, for example the pin 42 or the side stop 45. Preferably, all stop surfaces are made of wear-resistant materials. They can also have a wear-resistant coating. This can prevent the generation of particles in the event of a collision. Any particles that are nevertheless generated could be collected in a collecting container or in pockets that are formed by neighboring components.

Claims

Patent claims:

1. Facet mirror (7, 20) for an illumination optics (la) of a projection exposure system (1)

1.1. a multitude of displaceable single facets (8i, 2 li) with

1.1.1. a facet base body (35) and

1.1.2. a reflective surface (36) arranged on this,

1.2. characterized in that the individual facets (8i, 2E) are designed in such a way that mutual contact between adjacent individual facets (8i, 21i) is possible, but only in the area of stop surfaces formed in or on the basic facet body (35) and / or in the area of in or on the facet base body (35) arranged or ausgebil Deten stop elements (38).

2. Facet mirror (7, 20) for an illumination optics (la) of a projection exposure system (1)

2.1. a multitude of displaceable single facets (8i, 2 li) with

2.1.1. a facet base body (35) and

2.1.2. a reflective surface (36) arranged on this,

2.2. wherein at least a subset of the individual facets (8i, 21i) has a displacement area such that they touch a stop surface in one or more displacement positions.

3. facet mirror (7, 20) according to claim 1 or 2, characterized in that all individual facets (8i, 21,) in their respective basic position and / or in an active displacement position are spaced from all stop surfaces.

4. facet mirror (7, 20) according to any one of the preceding claims, characterized in that a subset of the individual facets (8i, 21,) has displacement areas such that adjacent individual _{facets (8i, 8i + i} , 20i, 20i _{+ i} ) in touch one or more displacement positions.

5. facet mirror (7, 20) according to any one of the preceding claims, characterized in that at least a subset of the individual facets (8i, 2E) is designed such that that adjacent individual facets (8i, 8i _{+ i} , 20i, 20i _{+ i} ) can touch in the area of a predetermined stop surface.

6. Facet mirror (7, 20) according to one of the preceding claims, characterized in that the stop surface is formed in or on the basic facet body (35) of a single facet (8i, 2h) or by a separate stop element (38).

7. facet mirror (7; 20) according to any one of the preceding claims, characterized in that the facet base body (35) are designed such that a distance between the facet base body (35) of two adjacent individual facets (8i, 8i _{+ i} , 20i, 20i _{+ i} ) is less than a distance between their reflection surfaces (36).

8. Facet mirror (7, 20) according to one of the preceding claims, characterized in that one or more attachment elements (38) are provided on or in the facet base body (35).

9. facet mirror (7, 20) according to one of claims 7 or 8, characterized in that the stop elements (38) have an extension in the direction parallel to the reflective surface (36) which is greater than the extension of the reflective surface (36) in this Direction and / or on the side of the facet base body (35) facing away from the reflective surface (36) protrude beyond the latter.

10. facet mirror (7, 20) according to any one of claims 7 to 9, characterized in that the stop elements (38) are arranged in pairs on the facet base body (35) that their outer envelope in a perpendicular projection to a sub-area of the enclosed by the envelope The reflective surface (36) protrudes beyond the reflective surface (36) in at least one direction.

11. Facet mirror (7, 20) according to one of the preceding claims, characterized by one or more means for limiting the displacement range of the individual facets (8i, 2h).

12. Single facet (8, 21) for a facet mirror (7, 20) with an illumination optics (la) of a projection exposure system (1)

12.1. a facet base body (35) and

12.2. a reflective surface (36) arranged on this,

12.3. characterized in that one or more stop surfaces and / or stop elements (38) are provided on or in the facet base body, which, when projected in the direction of a surface normal to the reflection surface, in at least one direction perpendicular to this surface normal over the reflection surface (36 ) survive.

13. Single facet (8, 21) according to claim 12, characterized in that it has one or more stop surfaces and / or stop elements (38) which, when projected in the direction of a surface normal onto the reflection surface, both in at least one direction perpendicular to this Surface normals and protrude in an opposite direction over the reflection surface (36).

14. Single facet (8, 21) according to one of claims 12 to 13, characterized in that it has one or more stop surfaces and / or stop elements (38) which, when projected in the direction of a surface normal onto the reflection surface over the entire circumferential area the reflective surface (36) over the reflective surface (36) hen.

15. Individual facet (8, 21) according to one of claims 12 to 14, characterized in that the projection is a parallel projection.

16. Single facet (8, 21) according to one of claims 12 to 15, characterized in that the projection is an orthogonal projection.

17. Individual facet (8, 21) according to one of claims 12 to 16, characterized in that the facet base body (35) and / or at least a subset of the stop elements (38) have an extension in the direction parallel to the reflective surface (36), which is greater than ßer than the extension of the reflection surface (36) in this direction.

18. Single facet (8, 21) according to one of claims 12 to 17, characterized in that at least a subset of the stop elements (38) on the side of the facet base body (35) facing away from the reflective surface (36) in at least one direction over this over to arise.

19. Single facet (8, 21) according to one of claims 12 to 18, characterized in that at least a subset of the stop elements (38)) are arranged in pairs on the facet base body (35) that their outer envelope in a perpendicular projection to one of the envelope enclosed partial surface of the reflective surface (36) protrudes in at least one direction over the reflective surface (36).

20. Single facet (8, 21) according to one of claims 12 to 19, characterized in that the facet base body (35) has at least one free end and a cross section of the facet base body (35) decreases towards the free end.

21. Individual facet (8, 21) according to one of claims 12 to 20, characterized in that the facet base body (35) has means for reducing the mass moment of inertia (I) and / or means for increasing the rigidity.

22. Single facet (8, 21) for a facet mirror (7, 20) of an illumination optics (la) with a projection exposure system (1)

22.1. a facet base body (35) and

22.2. a reflective surface (36) arranged on this,

22.3. characterized in that the facet base body (35) has means for reducing the mass moment of inertia (I) and / or means for increasing the rigidity.

23. Illumination optics (la) with at least one facet mirror (7, 20) according to one of claims 1 to 11.

24. Lighting system (lc) with

24.1. an illumination optics (la) according to claim 23 and

24.2. a radiation source (5) for generating illuminating radiation (4).

25. Optical system with 25.1. an illumination optics (la) according to claim 23 and

25.2. a projection optics (lb) for projecting an object field (2) into an image field.

26. Projection exposure system (1) with

26.1. a radiation source (5) for generating illuminating radiation (4), 26.2. an illumination optics (la) according to claim 23 and

26.3. a projection optics (lb) for projecting an object field (2) into an image field.

27. A method for producing a micro- or nano-structured component comprising the following steps: providing a projection exposure system according to claim 26,

Provision of a reticle with structures to be imaged,

Providing a wafer with a radiation-sensitive coating,

Imaging of the reticle structures to be imaged onto the wafer with the aid of the projection exposure system (1).

28. Component produced by a method according to claim 27.