DE102018216832A1 - Method for providing an optical assembly - Google Patents

Abstract

An optical assembly (M2) has an optical component (18, 19) with an optical surface (18), the final Nutzform is formed via a material removal. In the provision of a position of at least one bearing point (22) of the optical assembly on a support frame (23) enclosing providing the optical assembly (M2) a maximum material removal in the formation of the final useful shape of the optical surface (18) is specified. It is positioned taking into account the predetermined maximum material removal of the bearing point (22) and molded the final useful shape of the optical surface (18) by material removal. The result is an optical assembly in which on the one hand bearing forces do not exceed a permissible maximum and on the other hand an undesirable deformation of the optical surface due to force or torque influences during storage of the optical assembly is reduced or avoided altogether.

Description

The invention relates to a method for providing an optical assembly. Furthermore, the invention relates to an optical assembly provided by the method, to a projection optical system having such an optical assembly, to an optical system having such a projection optical system, to a projection exposure apparatus comprising such an optical system, to a method for producing a microstructured or nanostructured component with a Such Projektionsbelichtungsanlage and produced by this method micro- or nanostructured component.

Optical assemblies are known as mirrors or lenses with corresponding holders or sockets as components of projection optics for projection lithography, for example from the DE 10 2013 214 989 A1 , of the WO 2016/188934 A1 and the WO 2016/166080 A1 ,

It is an object of the invention to provide an optical assembly, in particular a mirror or a lens including its holder or mount for projection optics for use in projection lithography, in which on the one hand bearing forces do not exceed a permissible maximum and on the other an undesirable deformation of the optical surface due to force or torque influences during storage of the optical assembly is reduced or completely avoided.

This object is achieved by a method having the features specified in claim 1.

According to the invention, it has been recognized that in the case of a provisioning method in which a bearing point is positioned taking into account a predetermined maximum material removal during the formation of a final useful shape of the optical surface, it is possible, in particular unwanted torque contributions, which the optical assembly experiences via the bearing points to reduce and keep within predetermined and small tolerance values. It is then possible to select the bearing point so that it is located as little as possible from a center of gravity line of the optical assembly. Undesirable stresses induced in the optical surface are reduced or even completely avoided. The useful shape of the optical surface remains unaffected accordingly.

The use of a deviation function according to claim 2 in the positioning of the bearing point has been found to be particularly suitable for automated storage point positioning. The deviation function can be formulated with the aid of the principles of least squares.

The consideration of at least one manufacturing tolerance according to claim 3 improves the positioning of the bearing point. In particular, a tolerance in the production of a carrier of the optical component, for example a mirror carrier, can be taken into account. Such a manufacturing tolerance includes, for example, the tolerance of manufacturing typical dimensions of such a carrier.

A center of gravity measurement according to claim 4 can eliminate manufacturing tolerances of the optical assembly that affect a center of gravity.

An orientation of the optical system for measuring the center of gravity position according to claim 5 improves accuracy of the center of gravity measurement for the purpose of the bearing point positioning. The reference point can be regularly roughly predetermined, since apart from the removal of material in the formation of the final useful shape of the optical surface, the structure of the optical assembly and its material composition is known, so that the specification of a reference point, which is adjacent to the bearing point to be positioned, readily is possible. The reference point may be, for example, a raw bearing point that would result in a positioning without specification of the maximum material removal during the formation of the final useful shape of the optical surface. A center of gravity distance to the reference point, as measured in the direction of gravity, can be chosen to be less than 20 percent, less than 15 percent, less than 10 percent, or less than 5 percent of the center of gravity measurement typical extent of the optical assembly. When determining the typical extension of the optical assembly, edge lengths of a construction space cuboid, which is assumed by the optical assembly, can be used as a measure. The typical extent can then result as averaging according to the edge lengths along the dimensions of interest of such a construction space cuboid.

A positioning of the bearing point according to claim 6 has been found to be particularly suitable for a typical bearing structure of the optical assembly.

The advantages of an optical assembly according to claim 7 correspond to those which have already been explained above with reference to the erfmdungsgemäße method.

In the case of a mirror as an optical assembly according to claim 8, the advantages of the provisioning method are particularly effective. There, a focus of the optical assembly is often relatively far from the optical surface, so torque contributions can play a significant role in the storage of the optical assembly.

The advantages of a projection optical system according to claim 9, an optical system according to claim 10, a projection exposure apparatus according to claim 11, a manufacturing method for a micro- or nanostructured component according to claim 12 and a micro- or nanostructured component according to claim 13 correspond to those described above with reference have already been explained on the optical assembly according to the invention and its provision method. In particular, a semiconductor component, for example a memory chip, can be produced using the projection exposure apparatus.

The light source may be an EUV light source. A DUV light source, for example a light source with a wavelength of 193 nm, can also be used as an alternative.

• 1 schematisch eine Projektionsbelichtungsanlage für die EUV-Mikrolithographie;
• 2 in einem Meridionalschnitt eine Ausführung einer abbildenden Optik, die als Projektionsobjektiv in der Projektionsbelichtungsanlage nach 1 einsetzbar ist, wobei ein Abbildungsstrahlengang für Hauptstrahlen und für einen oberen und einen unteren Komastrahl dreier ausgewählter Feldpunkte dargestellt ist;
• 3 Randkonturen genutzter Spiegelflächen von Spiegeln der abbildenden Optik nach 2;
• 4 In einer stark schematischen Schnittdarstellung eine Optik-Baugruppe mit einer optischen Komponente in Form eines Spiegels mit einem Spiegelträger, der über mehrere Lagerpunkte an einem Tragrahmen gelagert ist, wobei zusätzlich noch auf die Lagerpunkte wirkende Kräfte mit Kräftepfeilen veranschaulicht sind.

An embodiment of the invention will be explained in more detail with reference to the drawing. In this show:

• 1 schematically a projection exposure system for EUV microlithography;
• 2 in a meridional section, an embodiment of an imaging optic, which follows as a projection objective in the projection exposure apparatus 1 is usable, wherein an imaging beam path for main beams and for an upper and a lower Komastrahl three selected field points is shown;
• 3 Edge contours of used mirror surfaces of mirrors of the imaging optics 2 ;
• 4 In a highly schematic sectional view of an optical assembly with an optical component in the form of a mirror with a mirror support, which is mounted on a support frame via a plurality of bearing points, wherein additionally acting on the bearing points forces are illustrated with force arrows.

A projection exposure machine 1 for microlithography has a light source 2 for illumination light or imaging light 3 , At the light source 2 it is an EUV light source that generates light in a wavelength range, for example between 5 nm and 30 nm, in particular between 5 nm and 15 nm. At the light source 2 it can be a plasma-based light source (laser-produced plasma (LPP), gas-generated plasma (GDP)) or even a synchrotron-based light source, for example a free-electron laser (FEL). At the light source 2 it may in particular be a light source with a wavelength of 13.5 nm or a light source with a wavelength of 6.9 nm. Other EUV wavelengths are possible. In general, even arbitrary wavelengths, for example visible wavelengths or also other wavelengths which can be used in microlithography (for example DUV, deep ultraviolet) and for the suitable laser light sources and / or LED light sources are available (for example 365 nm, 248 nm) nm, 193 nm, 157 nm, 129 nm, 109 nm) for the in the projection exposure apparatus 1 led lighting light 3 possible. A beam path of the illumination light 3 is in the 1 shown very schematically.

For guiding the illumination light 3 from the light source 2 towards an object field 4 in an object plane 5 serves a lighting optics 6 , With a projection optics or imaging optics 7 becomes the object field 4 in a picture field 8th in an image plane 9 mapped with a given reduction scale.

To facilitate the description of the projection exposure apparatus 1 as well as the different versions of the projection optics 7 in the drawing, a Cartesian xyz coordinate system is given, from which the respective positional relationship of the components shown in the figures results. In the 1 the x-direction is perpendicular to the plane of the drawing. The y-direction runs to the left and the z-direction to the top.

The object field 4 and the picture box 8th are in the projection optics 7 bent or curved and executed in particular partially annular. A radius of curvature of this field curvature can be 81 mm on the image side. A corresponding ring field radius of the image field is defined in FIG WO 2009/053023 A2 , A basic shape of a border contour of the object field 4 or the image field 8th is bent accordingly. Alternatively it is possible to use the object field 4 and the picture box 8th rectangular shape. The object field 4 and the picture box 8th have an xy aspect ratio greater than 1. The object field 4 thus has a longer object field dimension in the x direction and a shorter object field dimension in the y direction. These object field dimensions run along the field coordinates x and y.

In an exemplary embodiment of the projection optics 7 is an x-dimension of the image field of 26 mm and a y-dimension of the image field 8th of 1.2 mm in front.

The object field 4 is accordingly spanned by the first Cartesian object field coordinate x and the second Cartesian object field coordinate y. The third Cartesian coordinate z, which is perpendicular to these two object field coordinates x and y, is also called the normal coordinate.

For the projection optics 7 can that be in the 2 illustrated embodiment can be used. The optical design of the projection optics 7 after the 2 and 3 is known from the WO 2016/188934 A1 whose contents are fully referenced.

The picture plane 9 is in the projection optics 7 in the execution after 2 parallel to the object plane 5 arranged. Here, one is shown with the object field 4 coincident section of a reflection mask 10 , which is also called reticle. The reticle 10 is from a reticle holder 10a carried. The reticle holder 10a is powered by a reticle displacement drive 10b relocated.

The picture through the projection optics 7 takes place on the surface of a substrate 11 in the form of a wafer made by a substrate holder 12 will be carried. The substrate holder 12 is driven by a wafer or substrate displacement drive 12a relocated.

In the 1 is schematically between the reticle 10 and the projection optics 7 an incoming into this bundle of rays 13 of the illumination light 3 and between the projection optics 7 and the substrate 11 one from the projection optics 7 leaking radiation beam 14 of the illumination light 3 shown. An image field-side numerical aperture (NA) of the projection optics 7 is in the 1 not reproduced to scale.

The projection exposure machine 1 is the scanner type. Both the reticle 10 as well as the substrate 11 be during operation of the projection exposure system 1 scanned in the y direction. Also a stepper type of the projection exposure system 1 in which between individual exposures of the substrate 11 a gradual shift of the reticle 10 and the substrate 11 in the y-direction is possible. These displacements are synchronized with each other by appropriate control of the displacement drives 10b and 12a ,

The 2 shows the optical design of the projection optics 7 , The 2 shows the projection optics 7 in a meridional section, ie the beam path of the imaging light 3 in the yz plane. The projection optics 7 to 2 has a total of ten mirrors, in the order of the beam path of the individual beams 15 , starting from the object field 4 , numbered M1 to M10.

Shown in the 2 the beam path in each case three individual beams 15 , of three in the 2 go out to each other in the y-direction spaced object field points. Shown are main rays 16 , so individual rays 15 passing through the center of a pupil in a pupil plane of the projection optics 7 run, and in each case an upper and a lower coma beam of these two object field points. Starting from the object field 4 close the main beams 16 with a normal to the object plane 5 an angle CRA of 5.2 °.

The object plane 5 lies parallel to the image plane 9 ,

Shown in the 2 Parts of the calculated reflection surfaces of mirrors M1 to M10. A subarea of these calculated reflection surfaces is used. Only this actually used area of the reflection surfaces is actually present, plus a projection in the real mirrors M1 to M10.

3 shows this actually used area of the reflection surfaces of the mirrors M1 to M10. The mirror M10 has a passage opening 17 to the passage of the imaging light 3 which is reflected from the third last mirror M8 to the next to last mirror M9. The mirror M10 is around the passage opening 17 around used reflectively. All other mirrors M1 to M9 have no passage opening and are used in a coherently coherent area reflective.

The mirrors M1 to M10 are designed as freeform surfaces which can not be described by a rotationally symmetrical function. There are also other versions of the projection optics 7 possible, in which at least one of the mirrors M1 to M10 is designed as a rotationally symmetric asphere. An aspherical equation for such a rotationally symmetric asphere is known from US Pat DE 10 2010 029 050 A1 , All mirrors M1 to M10 can also be designed as such aspheres.

A free-form surface can be described by the following free-form surface equation (Equation 1): $$\begin{array}{l}Z=\frac{c_x{x}^2+{\mathrm{<figure-callout\; id="2"\; label="c\; y\; y"\; filenames="DE102018216832A1\_0007.png"\; state="\{\{state\}\}">c\; </figure-callout>}}_y{y}^{}{}^2}{1+\sqrt{1-\left(1+k_x\right){\left(c_{x}x\right)}^2-\left(1+k_y\right){\left(c_{y}y\right)}^2}}\hfill \\ +C_{1}x+C_{2}y\hfill \\ +{\text{C}}_3{\text{x}}^2+{\text{<figure-callout id="4" label="C" filenames="DE102018216832A1\_0007.png,DE102018216832A1\_0008.png" state="{{state}}">C</figure-callout>}}_{\text{4}}\text{xy}+{\text{C}}_5{\text{<figure-callout id="2" label="y" filenames="DE102018216832A1\_0007.png" state="{{state}}">y</figure-callout>}}^2\hfill \\ +{\text{C}}_6{\text{x}}^3+...{\text{C}}_9{\text{<figure-callout id="3" label="y" filenames="DE102018216832A1\_0007.png,DE102018216832A1\_0008.png" state="{{state}}">y</figure-callout>}}^3\hfill \\ +{\text{C}}_{10}{\text{x}}^4+...{\text{C}}_{12}{\text{x}}^2{\text{<figure-callout id="2" label="y" filenames="DE102018216832A1\_0007.png" state="{{state}}">y</figure-callout>}}^2+...{\text{C}}_{14}{\text{<figure-callout id="14" label="y" filenames="DE102018216832A1\_0007.png" state="{{state}}">y</figure-callout>}}^{14}\hfill \\ +{\text{C}}_{15}{\text{x}}^5+...{\text{C}}_{20}{\text{<figure-callout id="5" label="y" filenames="DE102018216832A1\_0007.png,DE102018216832A1\_0008.png" state="{{state}}">y</figure-callout>}}^5\hfill \\ +{\text{C}}_{21}{\text{x}}^6+...{\text{C}}_{24}{\text{x}}^3{\text{<figure-callout id="3" label="y" filenames="DE102018216832A1\_0007.png,DE102018216832A1\_0008.png" state="{{state}}">y</figure-callout>}}^3+...+{\text{C}}_{\text{27}}{\text{<figure-callout id="6" label="y" filenames="DE102018216832A1\_0007.png" state="{{state}}">y</figure-callout>}}^6\hfill \\ \hfill \end{array}$$

• Z ist die Pfeilhöhe der Freiformfläche am Punkt x, y, wobei x² + y² = r². r ist hierbei der Abstand zur Referenzachse der Freiformflächengleichung $$\left(\text{x}=0;\text{ y}=0\right).$$
  

For the parameters of this equation (1):

• Z is the arrow height of the freeform surface at point x, y, where x ² + y ² = r ² . Here r is the distance to the reference axis of the free-form surface equation $$\left(\text{x}=0;\text{y}=0\right),$$
  

In the free-form surface equation (1), C ₁ , C ₂ , C ₃ ... designate the coefficients of the free-form surface series expansion in the powers of x and y.

In the case of a conical base, c _x , c _{y is} a constant that corresponds to the vertex curvature of a corresponding asphere. So c _x = 1 / R _x and c _y = 1 / R _y . k _x and k _y each correspond to a conical constant of a corresponding asphere. The equation (1) thus describes a biconical freeform surface.

An alternatively possible free-form surface can be generated from a rotationally symmetrical reference surface. Such free-form surfaces for reflecting surfaces of the mirrors of projection optics of projection exposure apparatuses for microlithography are known from US Pat US 2007-0058269 A1 ,

Alternatively, freeform surfaces can also be described using two-dimensional spline surfaces. Examples include Bezier curves or nonuniform rational base splines (NURBS). For example, two-dimensional spline surfaces may be described by a network of points in an xy plane and associated z-values or by these points and their associated slopes. Depending on the particular type of spline surface, the complete surface is obtained by interpolation between the mesh points using, for example, polynomials or functions that have certain continuity and differentiability properties. Examples of this are analytical functions.

Each of the mirrors M1 to M10 is part of a respective optical assembly, which in the 4 the example of the mirror M2 is shown in schematic cross section.

A reflection surface 18 of the mirror M2 is part of a substrate 19 , The latter is with a mirror carrier 20 connected. An Indian 4 strongly schematically indicated cross-section of the mirror carrier 20 has the shape of a parallelogram. Over several camps 21 . 22 with corresponding bearing points is the mirror carrier 20 on a support frame 23 the projection optics 7 stored. Camps 21 . 22 and also the supporting frame 23 are in the 4 shown only schematically or in sections.

To the optical assembly of the mirror M2 belong to the substrate 19 , the mirror bearer 20 and the camps 21 . 22 ,

Camps 21 . 22 are equipped with actuators not shown on the adjustment of the reflection surface 18 within the projection optics 7 is possible.

Camps 21 . 22 can have a bearing bush, not shown in the drawing.

Details of the mirror M2 especially in the field of bearings 21 . 22 and in the region of the connection of the substrate 19 on the mirror carrier 20 are omitted.

Actually, the mirror carrier 20 stored over exactly three bearing points, namely on the bearing point of the camp 21 as well as two bearing points of two in the 4 bearing points of two bearings arranged at a distance from each other perpendicular to the plane of the drawing 22 of which in the 4 one is shown.

A focus SP of the mirror M2 is in the x-direction of the 4 by a distance Δx from the bearing point of the bearings 22 of the mirror M2 spaced.

To facilitate the description of power relations is in the 4 a Cartesian xy coordinate system specified, which has nothing to do with the coordinate system of 1 to 3 has to do. The x-direction runs in the 4 horizontally to the right and the y-direction runs vertically upwards.

Due to the weight of the mirror M2 results in a torque which is too horizontal directed force introduction components F ^x in the camp 21 . 22 leads. The associated force F ^x ₂₁ , which is at the bearing point of the bearing 21 attacks is in the 4 opposite to the x-direction, ie to the left in the mirror carrier 20 directed into it. The force component F ^x ₂₂ , which points to the bearing points of the bearings 22 is exercised in the positive x-direction, ie in the 4 directed to the right away from the center of gravity SP.

It also affects the bearings 22 nor a vertically directed in the positive y-direction force component F ^y ₂₂ as a counterforce to the weight of the game gel M2 acting in the negative y direction from the center of gravity SP. The amount of the respective force component F ^y ₂₂ corresponds to the weight of the mirror M2 on two camps 22 is distributed, the amount of half the weight of the mirror M2 ,

The final position of the center of gravity SP in the optical assembly of the mirror M2 results only after specification of a final useful form of the reflection surface 18 via a material-removing polishing of the substrate 19 ,

The positioning of the bearing points of the bearings 22 with regard to their x-coordinate, taking into account a corresponding material removal allowance, the following occurs:

First, a maximum material removal in the formation of the final useful shape of the reflection surface 18 specified. This maximum material removal can be, for example, the specification of a maximum polishing depth of the reflection surface 18 act. Together with the extent of the reflection surface in the dimensions x and y of the 3 , If necessary, including the extent of an existing passage opening, this can be the maximum material removal as maximum ablated weight of the substrate 19 pretend.

Taking into account this predetermined maximum material removal then the x-coordinate (after 4 ) of the bearing point of the bearings 22 relative to the mirror carrier 20 given and the bearings 22 become at this x-coordinate on the mirror carrier 20 manufactured. This is followed by the final useful form of the reflection surface 18 of the substrate 19 of the mirror M2 formed by material removal.

It then results due to this of the maximum possible Materialabtragabhängigen specification of the x-position of the bearing 22 correspondingly a maximum possible distance Δx of the center of gravity SP of the optical assembly of the mirror M2 from the bearing points of the bearings 22 and correspondingly maximum possible force components F ^x 22 and correspondingly F ^x 21 result.

An x positioning of the bearing points of the bearings 22 can be done taking into account a deviation function L (.DELTA.x), enter into the quadratic force or torque contributions.

In general, this deviation function L (.DELTA.x) z. B. have the following form: $$\text{L}\left(\mathrm{\Delta }\text{x}\right)={\text{F}}^{\text{x}}{}_{\text{base}}{\left(\mathrm{\Delta }\text{x}\right)}^2+{\text{F}}^{\text{x}}{}_{\text{pole}}{\left(\mathrm{\Delta }\text{x}\right)}^2+{\text{F}}^{\text{x}}{}_{\text{Tol}}{\left(\mathrm{\Delta }\text{x}\right)}^2$$

m ist hierbei die Masse der Optik-Baugruppe und g die Gravitationskonstante. Δy ist der y-Abstand zwischen dem Schwerpunkt SP und dem Lagerpunkt des Lagers 22 (vgl. 4).For the basic weight contribution F ^x base the following applies: $${\text{F}}^{\text{x}}{}_{\text{base}}=\mathrm{\Delta }\text{x mg}/\left(2\mathrm{\Delta }\text{y}\right)$$

Here m is the mass of the optical assembly and g is the gravitational constant. Δy is the y-distance between the center of gravity SP and the bearing point of the bearing 22 (see. 4 ).

x_s ist eine Mittelpunktskoordinate in x-Richtung eines maximalen Materi-alabtrages. Δm ist hierbei die Masse des vorgegebenen maximalen Materialabtrages.For the polish contribution F ^x _Pol applies: $${\text{F}}^{\text{x}}{}_{\text{pole}}=\left(\mathrm{\Delta }\text{x}+\left(\text{xs}-\mathrm{\Delta }\text{x}\right)\mathrm{\Delta }\text{m}/\text{m}\right)\left(\text{m}+\mathrm{\Delta }\text{m}\right)\text{G}/\left(2\mathrm{\Delta }\text{y}\right)$$

x _s is a mid-point coordinate in the x-direction of a maximum material transfer. Δm here is the mass of the predetermined maximum material removal.

The additional force component F ^x _Tol is a measure of the force / torque contribution due to manufacturing tolerances, in particular of the mirror carrier 20 the optical assembly of the mirror M2 , The following applies here: $${\text{F}}^{\text{x}}{}_{\text{Tol}}=\left(\mathrm{\Delta }\text{x}\pm \mathrm{\delta }\text{t}\pm \mathrm{\delta }\text{x}\right)\left(\text{m}\left(\text{G}+\mathrm{\delta }\text{G}\right)+\mathrm{\delta }\text{F}\right)/\left(2\left(\mathrm{\Delta }\text{y-}\mathrm{\delta }\text{y}\right)\right)$$

In this case, δt denote a manufacturing tolerance of the optical component surfaces and δx and δy maximum expected manufacturing tolerances of the mirror carrier 20 in the x and in the y direction of 4 ,

δg denotes a maximum expected deviation of a gravitational constant due to a difference of the gravitational constant between a place of manufacture and a place of use of the optical assembly with the mirror M2 ,

δx and δy can be in the range of 100 microns. δg can be in the range of 0.03 m / s ² .

δF denotes a possible error of a force determination.

In addition, when specifying the deviation function L, it can be taken into account that the Arguments x of the various force contributions F ^x _base (x), F ^x _Pol (x) and F ^x _Tol (x) are not independent of each other, but related to each other via a Politurtiefe or over tolerance contributions.

In the method of delivery described above, prior to positioning the bearing point, the bearing 22 a position of the center of gravity SP of the optical assembly of the mirror M2 be measured. Manufacturing tolerances of the optical assembly, which influence a center of gravity, can thus be eliminated.

To measure the center of gravity, the optical assembly of the mirror M2 be brought into an orientation in which a distance of the center of gravity SP to be measured to a reference point adjacent to the bearing point to be positioned, measured in a projection in the direction of gravity, be less than 25 percent of a typical extension of the optical assembly of the mirror M2 ,

The reference point may be a raw bearing point that has been roughly determined prior to the exact bearing point position determination.

Such an orientation for measuring the center of gravity is in the 4 assuming that the bearing point 22 coincides with the reference point shown. Such an orientation is for measuring the position of the center of gravity SP in the course of the provisioning process compared to, for example, a relative orientation 4 advantageous by 90 degrees about an axis tilted perpendicular to the xy plane orientation. A typical extension of the optical assembly is given for example by an average of the side lengths of the parallelogram cross-section of the mirror carrier 20 ,

A positioning of the bearing point of the bearing 22 can in the provision method via mounting the bearing bush in a bearing receptacle 24 one not in detail in the 4 shown component holder of the optical assembly of the mirror M2 respectively.

After providing the appropriate optics assemblies to the mirrors M1 to M10 after carrying out the above method involving the positioning of the bearing points is the projection exposure apparatus 1 operational.

The projection exposure apparatus is used to produce a microstructured or nanostructured component 1 used as follows: First, the reflection mask 10 or the reticle and the substrate or the wafer 11 provided. Subsequently, a structure on the reticle 10 on a photosensitive layer of the wafer 11 using the projection exposure system 1 projected. By developing the photosensitive layer, a micro or nanostructure is then formed on the wafer 11 and thus produces the microstructured component.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102013214989 A1 [0002]
• WO 2016/188934 A1 [0002, 0022]
• WO 2016/166080 A1 [0002]
• WO 2009/053023 A2 [0019]
• DE 102010029050 A1 [0032]
• US 20070058269 A1 [0037]

Claims (13)

A method of providing an optical assembly (M2) comprising an optical component (18, 19), the optical component (19) having an optical surface (18) whose final payload is formed via a material removal, including a prescription Position of at least one bearing point (22) of the optical assembly on a support frame (23), comprising the following steps: Predetermining a maximum material removal during the shaping of the final useful shape of the optical surface (18), - Positioning of the bearing point (22) taking into account the predetermined maximum material removal, - Forming the final useful shape of the optical surface (18) by material removal. Method according to Claim 1 , characterized in that the bearing point (22) is positioned taking into account a deviation function (L), wherein enter into the deviation function (L) square torque contributions. Method according to Claim 1 or 2 , characterized in that the bearing point (22) is positioned with additional consideration of at least one manufacturing tolerance of the optical assembly. Method according to one of Claims 1 to 3 , characterized in that prior to positioning of the bearing point (22) a position of a center of gravity (SP) of the optical assembly is measured. Method according to Claim 4 , characterized in that the optical assembly is brought to measure the center of gravity in an orientation in which a distance of the center of gravity (SP) to a reference point to be positioned bearing point (22) adjacent reference point, measured in a projection in the direction of gravity, is smaller than 25 percent of a typical extension of the optical assembly. Method according to one of Claims 1 to 5 characterized in that the bearing point (22) is positioned by mounting a bushing in a bearing receptacle (24) of a component mount of the optics assembly. Optical assembly (M2) provided by a method according to any one of Claims 1 to 6 , Optics module after Claim 7 , characterized by a reflection surface (18) as optical surface. Projection optics (7) with at least one on a support frame (23) mounted optical assembly (M2) according to one of Claims 7 or 8th , Optical system for use in projection lithography with projection optics (7) according to Claim 9 and with an illumination optical unit (6) for illuminating an object field (4) which can be imaged with the projection optics (7) with illuminating light (3) of a light source (2). Projection exposure system with an optical system after Claim 10 and a light source (2) for generating the illumination light (3). A method of fabricating a patterned device comprising the steps of: providing a reticle (10) and a wafer (11), projecting a pattern on the reticle (10) onto a photosensitive layer of the wafer (11) using the projection exposure apparatus Claim 11 , - Generating a micro or nanostructure on the wafer (11). Structured component produced by a method according to Claim 12 ,

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