IMAGING OPTICAL SYSTEM

Abstract

An imaging optical system for a projection exposure system has at least one anamorphically imaging optical element. This allows a complete illumination of an image field in a first direction with a large object-side numerical aperture in this direction, without the extent of the reticle to be imaged having to be enlarged and without a reduction in the throughput of the projection exposure system occurring.

Claims

1. An imaging optical system, comprising: an anamorphically imaging projection lens system having two principal planes and sign-identical imaging scales in the direction of the two principal planes, wherein the imaging optical system a microlithographic imaging optical system.

2.-20. (canceled)

21. The imaging optical system of claim 1, wherein the anamorphically imaging projection lens system comprises first and second part lens systems, and the first part lens system images anamorphically.

22. The imaging optical system of claim 1, wherein the anamorphically imaging projection lens system has a circular exit pupil.

23. The imaging optical system of claim 1, wherein the anamorphically imaging projection lens system comprises a least one mirror having a freeform face.

24. The imaging optical system of claim 1, wherein the imaging optical system has a first imaging scale in a first direction, the imaging optical system has a second imaging scale in a second direction, and the second imaging scale is at least one and a half times as large as the first imaging scale.

25. The imaging optical system of claim 1, wherein the imaging optical system has a direction-dependent object-side numerical aperture.

26. The imaging optical system of claim 1, wherein imaging optical system has: an image-side numerical aperture of at least 0.4; an object-side main beam angle for the field centre point of less than 7; and an image field having a width of more than 13 mm in a direction perpendicular to a scanning direction of the imaging optical system.

27. An illumination optical system, comprising: a pupil facet mirror, wherein the illumination optical system has an elliptical exit pupil with semi-axis lengths which differ from one another by at least 10%, and the illumination optical system is microlithographic illumination optical system.

28. The illumination optical system of claim 27, wherein the pupil facet mirror is elliptical and has semi-axis lengths which differ from one another by at least 10%.

29. An optical system, comprising: an imaging optical system of claim 1; and an illumination optical system configured to transfer radiation from a radiation source to an object field of the imaging optical system.

30. The optical system of claim 29, wherein the illumination optical system comprises a pupil facet mirror, the illumination optical system has an elliptical exit pupil with semi-axis lengths which differ from one another by at least 10%, and the illumination optical system is microlithographic illumination optical system.

31. A projection exposure system, comprising: a radiation source configured to produce radiation; and an optical system, comprising: an imaging optical system of claim 1; and an illumination optical system configured to transfer the radiation from the radiation source to an object field of the imaging optical system.

32. The projection exposure system of claim 31, wherein the illumination optical system comprises a pupil facet mirror, the illumination optical system has an elliptical exit pupil with semi-axis lengths which differ from one another by at least 10%, and the illumination optical system is microlithographic illumination optical system.

33. The projection exposure system of claim 31, further comprising a reticle holder which is displaceable in a scanning direction, wherein an imaging scale of the imaging optical system is smaller in the scanning direction than in a direction perpendicular to the scanning direction.

34. The projection exposure system of claim 33, further comprising a reticle having a width of at least 104 mm and a length of more than 132 mm.

35. A method, comprising: providing a projection exposure system, comprising: a radiation source configured to produce radiation; and an optical system, comprising: an imaging optical system of claim 1; and an illumination optical system; using the illumination optical system to illumination a reticle in an object plane of the imaging optical system; and using the imaging optical system to project a structure of the reticle onto a radiation-sensitive material.

36. The method of claim 35, wherein the illumination optical system comprises a pupil facet mirror, the illumination optical system has an elliptical exit pupil with semi-axis lengths which differ from one another by at least 10%, and the illumination optical system is microlithographic illumination optical system.

37. An optical system, comprising: an imaging optical system; and an illumination optical system of claim 27, wherein the illumination optical system is configured to transfer radiation from a radiation source to an object field of the imaging optical system.

38. A projection exposure system, comprising: a radiation source configured to produce radiation; and an optical system, comprising: an imaging optical system; and an illumination optical system according to claim 27, wherein the illumination optical system is configured to transfer radiation from a radiation source to an object field of the imaging optical system.

39. The projection exposure system of claim 38, further comprising a reticle holder which is displaceable in a scanning direction, wherein an imaging scale of the imaging optical system is smaller in the scanning direction than in a direction perpendicular to the scanning direction.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Further advantages and details of the disclosure emerge from the description of a plurality of embodiments with the aid of the drawings, in which:

[0026] FIG. 1 schematically shows a meridional section through a projection exposure system for EUV lithography;

[0027] FIG. 2 schematically shows a cutout of the projection exposure system according to FIG. 1 to illustrate the beam path in the imaging optical system according to a first embodiment;

[0028] FIG. 3 shows a view in accordance with FIG. 2 in a plane perpendicular thereto;

[0029] FIGS. 4 and 5 show views according to FIGS. 2 and 3 of a further embodiment;

[0030] FIGS. 6 and 7 show corresponding views of a third embodiment; and

[0031] FIGS. 8 and 9 show corresponding views of a fourth embodiment.

DETAILED DESCRIPTION

[0032] FIG. 1 schematically shows, in a meridional section, the components of a projection exposure system 1 for microlithography. An illumination system 2 of the projection exposure system 1, apart from a radiation source 3, includes an illumination optical system 4 for exposing an object field 5 in an object plane 6. A reticle 7, which is arranged in the object field 5 and is held by a reticle holder 8, only shown cutout-wise, is exposed here.

[0033] A projection optical system 9 indicated only schematically in FIG. 1 is used to image the object field 5 in an image field 10 in an image plane 11. The projection optical system 9 is therefore also designated an imaging optical system. A structure on the reticle 7 is imaged on a light-sensitive layer of a wafer 12 which is arranged in the region of the image field 10 in the image plane 11 and is held by a wafer holder 13 also shown schematically.

[0034] The radiation source 3 is an EUV radiation source which emits EUV radiation 14. The wavelength of the emitted useful radiation of the EUV radiation source 3 is in the range from 5 nm to 30 nm. Other wavelengths, which are used in lithography, and are available for suitable light sources, are also possible. The radiation source 3 may be a plasma source, for example a DPP source or an LPP source. A radiation source based on a synchrotron can also be used as the radiation source 3. Information on a radiation source of this type can be found by the person skilled in the art, for example, in U.S. Pat. No. 6,859,515 B2. A collector 15 is provided to bundle the EUV radiation 14 from the EUV radiation source 3.

[0035] The EUV radiation 14 is also designated illumination light or imaging light.

[0036] The illumination optical system 4 includes a field facet mirror 16 with a large number of field facets 17. The field facet mirror 16 is arranged in a plane of the illumination optical system 4, which is optically conjugated to the object plane 6. The EUV radiation 14 is reflected by the field facet mirror 16 to a pupil facet mirror 18 of the illumination optical system 4. The pupil facet mirror 18 has a large number of pupil facets 19. The field facets 17 of the field facet mirror 16 are imaged in the object field 5 with the aid of the pupil facet mirror 18.

[0037] For each field facet 17 on the field facet mirror 16, there is precisely one associated pupil facet 19 on the pupil facet mirror 18. Between a field facet 17 and a pupil facet 19, in each case, a light channel is configured. The facets 17, 19 of at least one of the facet mirrors 16, 18 may be switchable. For this purpose, a microelectromechanical system (MEMS) may be provided. The facets 17, 19 may, in particular, be tiltably arranged on the facet mirror 16, 18. It is possible here to only configure a part, for example at most 30%, at most 50% or at most 70% of the facets 17, 19 to be tiltable. It may also be provided that all the facets 17, 19 are tiltable. The switchable facets 17, 19 are, in particular, the field facets 17. By a tilting of the field facets 17, the allocation thereof to the respective pupil facets 19 and therefore the configuration of the light channels can be varied. For further details of the facet mirrors 16, 18 with tiltable facets 17, 19 and further details of the illumination optical system 4, reference is made to DE 10 2008 009 600 A1.

[0038] The illumination optical system 4 may also have further mirrors 20, 21 and 22, which form a transmission optical system 23. The last mirror 22 of the transmission optical system 23 is a grazing incidence mirror. The pupil facet mirror 18 and the transmission optical system 23 form a following optical system for transferring the illumination light 14 into the object field 5. The transmission optical system 23 can be dispensed with, in particular, when the pupil facet mirror 18 is arranged in an entry pupil of the projection optical system 9.

[0039] The illumination optical system 4 has an exit pupil with a shape adapted to (e.g., corresponding to) the shape of an entry pupil of the projection optical system 9. The exit pupil of the illumination optical system 4 is, in particular, elliptical. This can be achieved, in particular, by an elliptically configured pupil facet mirror 18. As an alternative to this, the pupil facets 19 can also be arranged on the pupil facet mirror 18 in such a way that they have an elliptically configured envelope.

[0040] The semi-axes of the elliptical pupil facet mirror 18 have, in particular, two different semi-axis lengths, the greater semi-axis length in particular being at least one and a half times as great, in particular at least twice as great, as the first semi-axis length. The semi-axis lengths are, in particular, in the ratio 1:2, 1:3, 1:4, 1:5, 1:6, 1:8, 1:10, 2:3, 2:5 or 3:4.

[0041] The semi-axes of the exit pupil of the illumination optical system 4 therefore have two different semi-axis lengths, the greater semi-axis length in particular being at least one and a half times as great, in particular at least twice as great, as the first semi-axis length. The semi-axis lengths are, in particular in the ratio 1:2, 1:3, 1:4, 1:5, 1:6, 1:8, 1:10, 2:3, 2:5 or 3:4.

[0042] For a simpler description of positional relationships, a Cartesian xyz-coordinate system is drawn in the figures, in each case. The x-axis in FIG. 1 runs perpendicular to the plane of the drawing and into it. The y-axis runs to the right. The z-axis runs downward. The object plane 6 and the image plane 11 both run parallel to the xy-plane.

[0043] The reticle holder 8 can be displaced in a controlled manner so that in the projection exposure system, the reticle 7 can be displaced in a displacement direction in the object plane 6. Accordingly, the wafer holder 13 can be displaced in a controlled manner so that the wafer 12 can be displaced in a displacement direction in the image plane 11. As a result, the reticle 7 can be scanned through the object field 5, and the wafer 12 can be scanned through the image field 10. The displacement direction in the figures is parallel to the y-direction. It will also be designated the scanning direction below. The displacement of the reticle 7 and the wafer 12 in the scanning direction can preferably take place synchronously with respect to one another.

[0044] FIGS. 2 and 3 show the optical design of a first configuration of the projection optical system 9. The beam path of individual beams of the radiation 14 extending from a central object field point and from two respective object field points defining the two opposing edges of the object field 5 are shown. The projection optical system 9 according to FIGS. 2 and 3 has a total of six mirrors, which are numbered consecutively M1 to M6 proceeding from the object field 5 in the direction of the beam path. The reflection faces of the mirrors M1 to M6 calculated in the design of the projection optical system 9 are shown in the figures. Only one section of the faces shown is partially actually used for the reflection of the radiation 14, as can be seen from the figures. The actual configuration of the mirrors M1 to M6, in other words, may be smaller than shown in the figures (the actual configuration may include only part of the calculated reflection face shown in the figures).

[0045] A pupil face 24 is located between the mirror M2 and the mirror M3. The pupil face 24 is not necessarily flat. It may be curved. Moreover, an intermediate image face 25 is located between the mirror M4 and the mirror M5. The intermediate image face 25 is not necessarily flat. It may be curved. The mirrors M1 to M4 therefore form a first part lens system 26. The mirrors M5 and M6 form a second part lens system 27.

[0046] The first part lens system 26 is an anamorphic lens, i.e. it images anamorphically. The second part lens system 27 is also an anamorphic lens, i.e. it images anamorphically. It is likewise possible, however, for the second part lens system 27 to be configured to be non-anamorphic.

[0047] At least one of the mirrors M1 to M6 is configured to be an anamorphically imaging optical element. The projection optical system 9 includes, in particular, at least one anamorphically imaging mirror, such as at least two anamorphically imaging mirrors, at least three anamorphically imaging mirrors, at least four anamorphically imaging mirrors, at least five anamorphically imaging mirrors, at least six anamorphically imaging mirrors, at least seven anamorphically imaging mirrors, at least eight anamorphically imaging mirrors.

[0048] The projection optical system 9 therefore has, in a first direction, a first imaging scale and, in a second direction, a second imaging scale which is different from this. The second imaging scale is, in particular, at least one and a half times as great, in particular at least twice as great, as the first imaging scale.

[0049] The projection optical system 9 is, in particular, configured so that the amount of the imaging scale in the scanning direction is smaller than the amount of the imaging scale in a direction perpendicular to the scanning direction. The amount of the imaging scale in the scanning direction is, in particular, at most three quarters as great (e.g., at most two thirds as great, at most half as great) as the imaging scale in a direction perpendicular to the scanning direction.

[0050] The projection optical system 9 has a direction-dependant object-side numerical aperture (NAO), i.e. the entry pupil deviates from the circular shape. The object-side numerical aperture (NAO) in a specific direction, namely in the direction of the large imaging scale, is in particular at least one and a half times as large (e.g., at least twice as large) as in a direction perpendicular thereto.

[0051] The mirror M6 has a through-opening 28 for radiation 14 to pass through. Located between the mirrors M5 and M6 is a further pupil face 29. The pupil face 29 is not necessarily flat. It may be curved.

[0052] The mirrors M1 to M6 are configured to reflect EUV radiation. They carry, in particular, multiple reflection layers for optimising their reflection for the impinging EUV illumination light 14. The reflection can be all the better optimised, the closer the impingement angle of the individual beams on the mirror surfaces to the perpendicular incidence.

[0053] The mirrors M1 to M5 have reflection faces, which are closed, in other words without a through-opening.

[0054] The mirrors M1, M4 and M6 have concave reflection faces. The mirrors M2, M3 and M5 have convex reflection faces.

[0055] The mirrors M1 to M6 of the projection optical system 9 are configured as freeform faces that cannot be described by a rotationally symmetrical function. Other configurations of the projection optical system 9 are also possible, in which at least one of the mirrors M1 to M6 has a freeform reflection face of this type. A freeform face of this type may be produced from a rotationally symmetrical reference face. Freeform faces of this type for reflection faces of the mirrors of projection optical systems of projection exposure systems for microlithography are known from US 2007-0058269 A1.

[0056] The freeform face can be mathematically described by the following equation:

[00001]$Z\left(x,y\right)=\frac{{\mathrm{cr}}^2}{1+\sqrt{1-\left(1+k\right).Math.c^2.Math.r^2}}+\underset{j=2}{\overset{N}{.Math.}}.Math.\frac{C_j}{N_{\mathrm{radius}}^{m+n}}.Math.x^m.Math.y^n$

wherein there applies:

[00002]$j=\frac{{\left(m+n\right)}^2+m+3.Math.n}{2}+1$

Z is the arrow height of the freeform face at the point x, y, wherein

x.sup.2+y.sup.2=r.sup.2.

c is a constant, which corresponds to the summit of the curve of a corresponding asphere. k corresponds to a conical constant of a corresponding asphere. C.sub.j are the coefficients of the monomials x.sup.my.sup.n. Typically, the values of c, k and C.sub.j are determined on the basis of the desired optical properties of the mirror within the projection optical system 9. N.sub.radius is a standardisation factor for the coefficients C.sub.j. The order of the monomial, m+n, can be varied as desired. A higher order monomial can lead to a design of the projection optical system with better image error correction, but is, however, more complex to calculate. m+n can adopt values between 3 and more than 20.

[0057] Freeform faces can be mathematically described by Zernike polynomials, which, for example, are described in the manual of the optical design program CODE V. Alternatively, freeform faces can be described with the aid of two-dimensional spline surfaces. Examples of this are Bezier curves or non-uniform rational basis splines (NURBS). Two-dimensional spline surfaces may, for example, be described by a network of points in an xy-plane and associated z-values or by these points and gradients pertaining to them. Depending on the respective type of spline surface, the complete surface is obtained by interpolation between the network points using, for example, polynomials or functions, which have specific properties with regard to their continuity and differentiability. Examples of this are analytical functions.

[0058] Optical design data of the projection optical system 9 will be summarised below in tables, the data having been obtained with the aid of the optical design program Code V.

[0059] The first of the following tables gives for the optical surfaces of the optical components and for the aperture stop, in each case, the reciprocal value of the summit of the curve (radius) and a thickness, which corresponds to the z-spacing of adjacent elements in the beam path, proceeding from the image plane 11, in other words counter to the light direction. The second table gives the coefficients C.sub.j of the monomials)(my in the freeform face equation given above for the mirrors M1 to M6.

[0060] In a further table, the amount in mm is also given, along which the respective mirror, proceeding from a mirror reference design was decentred (Y-decentre) and rotated (X-rotation). This corresponds to a parallel displacement and a tilting in the freeform face design method. The displacement takes place in the y-direction here and the titling is about the x-axis. The angle of rotation is given here in degrees.

TABLE-US-00001 Surface Radius Thickness Operating mode image plane INFINITE 852.884 M6 889.919 802.884 REFL M5 219.761 1800.787 REFL M4 999.946 434.619 REFL M3 1033.356 483.832 REFL M2 2464.083 947.116 REFL M1 1323.688 1047.116 REFL object plane INFINITE 0.000

TABLE-US-00002 Coefficient M6 M5 M4 K 3.303831E03 2.041437E02 1.056546E01 Y 0.000000E+00 0.000000E+00 0.000000E+00 X2 1.106645E+00 4.620513E+00 1.065419E+00 Y2 1.316656E+00 4.632819E+00 2.089523E+00 X2Y 6.987016E02 6.244905E02 2.322141E01 Y3 1.544816E01 2.303227E01 2.158981E01 X4 3.297744E02 9.371547E02 7.579352E02 X2Y2 6.476911E02 1.671737E01 8.744751E02 Y4 5.431530E02 7.743085E02 2.360575E01 X4Y 7.040479E04 4.607809E03 3.961681E03 X2Y3 6.159827E03 1.034287E02 9.782459E03 Y5 4.061987E03 3.840440E03 1.297054E01 X6 1.398226E03 3.085471E03 6.847894E03 X4Y2 2.977799E03 8.906352E03 6.372742E03 X2Y4 4.433992E03 8.678073E03 2.569810E02 Y6 1.255594E03 1.683572E03 9.106731E02 X6Y 2.969767E04 1.881484E04 1.342374E03 X4Y3 2.820109E04 1.123168E03 5.896992E03 X2Y5 3.654895E04 5.949903E04 1.660704E03 Y7 8.966891E05 3.952323E04 3.764049E02 Nradius 2.899772E+02 6.300046E+01 2.064580E+02

TABLE-US-00003 Coefficient M3 M2 M1 K 5.744686E01 3.325393E+02 1.583030E02 Y 0.000000E+00 0.000000E+00 0.000000E+00 X2 3.551408E01 3.277030E01 2.811984E02 Y2 2.123536E+00 1.609563E+00 4.135835E01 X2Y 2.013521E01 6.948142E01 3.866470E02 Y3 1.210907E02 3.694447E01 1.853273E02 X4 5.478320E02 1.369729E01 1.349339E03 X2Y2 7.482002E02 1.984843E01 3.032808E03 Y4 8.327949E02 1.227576E01 2.824781E03 X4Y 2.048831E03 4.568931E02 4.300195E04 X2Y3 4.029059E03 1.713508E02 6.501645E04 Y5 1.415756E02 6.185385E03 3.144628E03 X6 1.998416E04 1.834856E02 6.906841E05 X4Y2 1.979383E03 3.309794E02 5.274081E05 X2Y4 5.943296E03 5.169942E02 1.330272E03 Y6 1.246118E03 1.603819E01 1.363317E02 X6Y 1.584327E04 7.876367E03 2.377257E05 X4Y3 3.187207E04 1.244804E02 2.251271E04 X2Y5 5.566691E04 5.746055E02 9.996573E04 Y7 1.399787E03 3.870909E02 4.001012E03 Nradius 8.132829E+01 7.472082E+01 1.311311E+02

TABLE-US-00004 Image Coefficient M6 M5 M4 M3 M2 M1 plane Y-decentre 51.252 99.408 123.654 215.631 528.818 512.855 0.000 X-rotation 0.323 7.067 2.444 10.483 16.940 3.488 0.000

[0061] The projection optical system 9, in the y-direction, i.e. in the scanning direction, has an imaging scale of 1:8, i.e., the reticle 7 in the object field 5, in the scanning direction, is eight times as great as its image in the image field 10. The projection optical system 9, in the x-direction, i.e. perpendicular to the scanning direction, has an imaging scale of 1:4. The projection optical system 9 is therefore reducing. An image-side numerical aperture of the projection optical system 9 is 0.5. The image-side numerical aperture of the projection optical system 9 is, in particular, at least 0.4. The image field 10 has a size of 2 mm26 mm, wherein the 2 mm is in the scanning direction and the 26 mm is perpendicular to the scanning direction. In particular in the scanning direction, the image field 10 may also have a different size. The size of the image field 10 is at least 1 mm10 mm. Perpendicular to the scanning direction, the image field 10, in particular, has a width of more than 13 mm. The image field 10 is, in particular, rectangular. The projection optical system 9, in particular, has an image-side scanning slot width of at least 13 mm, in particular more than 13 mm, in particular at least 26 mm. The projection optical system 9 has an object-side main beam angle for the field centre point of 6. The object-side main beam angle for the field centre point is, in particular at most 7. It has an optical overall length of 2000 mm.

[0062] The object field 5 in this embodiment has a size of 16 mm104 mm. In this case, the 16 mm is in the scanning direction and the 104 mm is perpendicular to the scanning direction.

[0063] The reticle 7 is also adapted to the different imaging scales in the scanning direction and perpendicular thereto. It has structures with different minimal structure sizes in the scanning direction and in the direction perpendicular thereto. The structures on the reticle 7 may have, in the scanning direction and in the direction perpendicular to this, in particular, dimensions, which are, in each case, an integral multiple of these minimal structure sizes. The ratio of the minimal structure sizes in the scanning direction and perpendicular to this is precisely inversely proportional to the ratio of the imaging scales in these directions. The minimal structure sizes in the scanning direction and perpendicular to this differ, in particular, by at least 10%, in particular at least 20%, in particular at least 50% from one another.

[0064] The reticle 7 has a width in the direction perpendicular to the scanning direction of at least 104 mm. The reticle 7, in particular, has a length adapted to the stronger reduction in the scanning direction. The reticle 7 has, in particular, a width of 104 mm and a length of 264 mm. The length of the reticle is, in particular, greater than 132 mm. It is, in particular, at least 140 mm, in particular at least 165 mm, in particular at least 198 mm.

[0065] A further configuration of the projection optical system 9, which can be used in the projection exposure system 1, is shown in FIGS. 4 and 5. Components which correspond to those which have already been described above with reference to FIGS. 2 and 3 have the same reference numerals and will not be discussed again in detail.

[0066] The mirror M3 has no through-opening in the optically used region. However, the mechanical configuration of the mirror M3 may be selected such that the light, which runs from the mirror M4 to the mirror M5, passes through a mirror opening of the monolithically configured mirror body of M3.

[0067] The mirrors M1, M3, M4 and M6 have concave reflection faces. The mirrors M2 and M5 have convex reflection faces.

[0068] In this embodiment, the beam path between the mirrors M2 and M3 intersects with the beam path between the mirrors M4 and M5.

[0069] In this embodiment, the mirror M5, relative to the image field 10 in the scanning direction, is arranged on the same side as the object field 5.

[0070] The optical design data of the projection optical system 9 according to FIGS. 4 and 5 will in turn be summarised in tables below. The mathematical description of the freeform faces corresponds to that which has already been described above with reference to the configurations according to FIGS. 2 and 3. The structure of the tables with respect to the configuration according to FIGS. 4 and 5 also corresponds to that with respect to the configuration according to FIGS. 2 and 3.

TABLE-US-00005 Surface Radius Thickness Operating mode image plane INFINITE 689.272 M6 731.552 639.272 REFL M5 241.671 1420.179 REFL M4 1500.000 580.907 REFL M3 1422.356 1010.728 REFL M2 661.083 1110.728 REFL M1 1384.311 1210.728 REFL object plane INFINITE 0.000

TABLE-US-00006 Coefficient M6 M5 M4 K 0.000000E+00 0.000000E+00 0.000000E+00 Y 0.000000E+00 0.000000E+00 0.000000E+00 X2 1.697113E+00 4.496118E+00 1.030719E+01 Y2 1.683950E+00 4.083378E+00 1.147196E+01 X2Y 1.755515E01 3.170399E01 1.434807E+00 Y3 2.279761E02 9.028788E02 1.085004E+00 X4 5.443962E02 4.335109E02 2.308628E01 X2Y2 1.503579E01 8.531612E02 7.598943E01 Y4 5.203904E02 6.130679E02 2.980202E01 X4Y 5.039890E03 1.771794E02 8.711086E03 X2Y3 8.907227E03 1.404665E02 8.302498E04 Y5 5.015844E03 8.045746E03 4.101109E02 Nradius 2.899772E+02 6.300046E+01 2.064580E+02

TABLE-US-00007 Coefficient M3 M2 M1 K 0.000000E+00 0.000000E+00 0.000000E+00 Y 0.000000E+00 0.000000E+00 0.000000E+00 X2 4.645076E01 5.243755E01 3.303400E01 Y2 2.057326E01 2.274245E02 7.527525E01 X2Y 3.583366E02 1.523089E+00 2.593623E03 Y3 3.371920E02 2.167244E+00 3.182409E02 X4 9.534050E05 7.127442E02 8.002659E04 X2Y2 4.301563E03 3.064519E01 5.376311E03 Y4 9.145920E04 7.458445E01 7.154305E03 X4Y 9.453851E05 1.770844E01 2.938545E04 X2Y3 2.757417E04 2.079536E01 2.101675E03 Y5 4.683904E05 1.544216E01 6.098608E04 Nradius 8.132829E+01 7.472082E+01 1.311311E+02

TABLE-US-00008 Image Coefficient M6 M5 M4 M3 M2 M1 plane Y-decentre 0.000 99.374 121.476 185.579 311.769 482.388 0.000 X-rotation 4.418 8.837 1.271 16.249 8.734 1.361 0.000

[0071] FIGS. 6 and 7 show a further design of the projection optical system 9, which can be used in the projection exposure system 1. Components which correspond to those which have already been described above with reference to FIGS. 2 and 3 have the same reference numerals will not be discussed again in detail.

[0072] The projection optical system 9 according to FIGS. 6 and 7 has a total of six mirrors M1 to M6, which are numbered consecutively M1 to M6 in the direction of the beam path proceeding from the object field 5. The projection optical system 9 according to FIGS. 6 and 7 has an optical overall length of 1865 mm.

[0073] The mirrors M1, M4 and M6 have a concave reflection face. The mirror M5 has a convex reflection face. The mirrors M2 and M3 are convex in one direction and concave in the orthogonal direction with respect thereto, in other words have the form of a saddle face in the centre point of the mirror.

[0074] The mirror M5 is also arranged in this embodiment, in the scanning direction with respect to the image field 10, on the same side as the object field 5.

[0075] The optical design data of the projection optical system 9 according to FIGS. 6 and 7 will in turn be shown in tables below. The mathematical description of the freeform faces corresponds to that which was already described above with reference to the configuration according to FIGS. 2 and 3. The structure of the tables with respect to the configuration according to FIGS. 6 and 7 also corresponds to that with respect to the configuration according to FIGS. 2 and 3.

TABLE-US-00009 Surface Radius Thickness Operating mode image plane INFINITE 752.663 M6 770.716 702.663 REFL M5 150.912 1382.613 REFL M4 996.191 579.950 REFL M3 3722.693 805.250 REFL M2 19143.068 805.250 REFL M1 1526.626 1011.848 REFL object plane INFINITE 0.000

TABLE-US-00010 Coefficient M6 M5 M4 K 0.000000E+00 0.000000E+00 0.000000E+00 Y 0.000000E+00 0.000000E+00 0.000000E+00 X2 1.014388E+00 5.967807E+00 1.640439E+00 Y2 9.176806E01 5.297172E+00 1.185698E+01 X2Y 2.666213E02 2.932506E02 5.795084E01 Y3 1.276213E02 1.747940E01 2.665088E01 X4 3.194237E02 1.741906E01 4.142971E02 X2Y2 5.891573E02 4.136465E01 2.431409E02 Y4 2.892148E02 1.408837E01 8.604418E01 X4Y 5.053354E04 8.947414E03 1.339774E03 X2Y3 3.013407E03 4.414092E02 2.210148E02 Y5 2.088577E03 3.281648E02 1.242199E+00 Nradius 2.899772E+02 6.300046E+01 2.064580E+02

TABLE-US-00011 Coefficient M3 M2 M1 K 0.000000E+00 0.000000E+00 0.000000E+00 Y 0.000000E+00 0.000000E+00 0.000000E+00 X2 3.018727E+00 4.089101E01 1.333076E01 Y2 2.571222E+00 3.746969E+00 8.408741E01 X2Y 2.111739E01 1.877269E01 3.355099E02 Y3 1.035192E03 1.810657E01 3.518765E03 X4 9.587021E05 1.882449E03 2.861048E03 X2Y2 2.154549E02 8.492037E02 3.127905E02 Y4 1.331548E02 4.386749E01 7.200871E03 X4Y 3.718201E03 6.344503E03 2.655046E04 X2Y3 4.305507E03 1.265202E01 6.358900E03 Y5 5.587835E03 6.311675E01 1.276179E02 Nradius 8.132829E+01 7.472082E+01 1.311311E+02

TABLE-US-00012 Image Coefficient M6 M5 M4 M3 M2 M1 plane Y-decentre 11.861 78.940 76.134 224.849 34.161 393.420 0.000 X-rotation 4.070 6.401 16.914 20.375 18.683 9.044 0.000

[0076] FIGS. 8 and 9 show a further configuration of a projection optical system 9, which can be used in the projection exposure system 1. Components which correspond to those which have already been described above with reference to FIGS. 2 and 3 have the same reference numerals and will not be discussed again in detail.

[0077] The projection optical system 9 according to FIGS. 8 and 9 has eight mirrors M1 to M8. The mirrors M1 to M6 form the first part lens system 26. The mirrors M7 and M8 form the second part lens system 27. The mirror M8, within the optical useful region, has the through-opening 28 for imaging light to pass through. The mirrors M1 to M7 have reflection faces, which are closed, in other words without a through-opening within the optical useful region. The projection optical system 9 according to FIGS. 8 and 9 therefore has precisely one mirror with a through-opening 28 within the optical useful region. Obviously, it is also possible to configure a projection optical system 9 with eight mirrors M1 to M8, of which more than one has a through-opening within the optical useful region.

[0078] The pupil face 24 is located in the beam path between the mirrors M3 and M5. The pupil face 29 is located between the mirrors M7 and M8. The projection optical system 9 according to FIGS. 8 and 9 also has two part lens systems 26, 27. It produces precisely one intermediate image, which lies geometrically in the region of the through-opening of the mirror M8.

[0079] The mirrors M1, M2, M6 and M8 have a concave reflection face. The mirror M7 has a convex reflection face.

[0080] The projection optical system according to FIGS. 8 and 9 has an image-side numerical aperture of 0.65. The optical design data of the projection optical system 9 according to FIGS. 8 and 9 are summarised below in tables as in the preceding examples.

TABLE-US-00013 Surface Radius Thickness Operating mode image plane INFINITE 845.498 M8 876.024 795.498 REFL M7 180.463 1850.000 REFL M6 1124.587 954.502 REFL M5 488.461 539.347 REFL M4 385.935 268.946 REFL M3 899.608 563.864 REFL M2 1862.135 962.532 REFL M1 5181.887 1182.769 REFL object plane INFINITE 0.000

TABLE-US-00014 Coefficient M8 M7 M6 M5 K 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 Y 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X2 3.488069E+00 1.173931E+01 2.308119E+01 1.973785E+01 Y2 2.635738E+00 1.010579E+01 9.438034E+00 5.768532E+00 X2Y 3.059528E01 2.733318E01 2.266607E+00 2.615013E+00 Y3 4.818868E03 6.423471E01 4.511519E01 3.223897E+00 X4 1.179868E01 5.618198E01 1.276169E+00 3.423570E01 X2Y2 3.744431E01 9.722072E01 1.994073E+00 1.253707E+00 Y4 1.874806E01 5.624878E01 9.258956E01 1.143661E+00 X4Y 4.142568E03 7.747318E03 2.207925E01 2.696457E02 X2Y3 2.457062E02 2.657340E02 4.677376E02 1.053608E01 Y5 1.021381E02 2.031996E02 3.450492E01 1.716687E+00 X6 1.995975E02 5.531407E02 1.199126E01 1.472679E02 X4Y2 4.538384E02 1.603998E01 2.637967E01 4.745154E02 X2Y4 5.093101E02 1.653739E01 3.269947E01 4.959237E01 Y6 1.573648E02 6.733509E02 1.107783E01 1.594589E+00 X6Y 4.813461E03 1.089425E03 8.010947E02 1.168696E04 X4Y3 6.317680E03 3.797390E03 4.398398E03 1.681727E02 X2Y5 4.665516E03 6.378254E03 1.634222E02 8.741752E01 Y7 1.452902E03 1.323361E03 8.378471E01 2.083305E01 X8 2.243101E03 8.933777E03 9.452801E03 8.039655E04 X6Y2 1.043837E02 3.095089E02 9.332196E02 5.834641E03 X4Y4 1.610588E02 4.686597E02 1.032458E01 1.262475E01 X2Y6 1.112924E02 3.372176E02 1.634446E01 2.791598E01 Y8 2.847098E03 9.333073E03 6.596064E01 3.828685E01 X8Y 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X6Y3 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X4Y5 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X2Y7 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 Y9 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X10 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X8Y2 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X6Y4 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X4Y6 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X2Y8 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 Y10 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 Nradius 4.270420E+02 8.460702E+01 3.587547E+02 1.359154E+02

TABLE-US-00015 Coefficient M4 M3 M2 M1 K 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 Y 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X2 7.762408E+00 0.000000E+00 0.000000E+00 2.415351E+01 Y2 5.991623E+00 2.100665E+01 1.742497E+01 2.450758E+01 X2Y 9.407982E01 1.845560E+01 0.000000E+00 2.857360E+00 Y3 7.990315E02 1.826735E+00 0.000000E+00 8.203766E01 X4 2.084759E01 0.000000E+00 0.000000E+00 1.195250E01 X2Y2 2.343824E01 0.000000E+00 0.000000E+00 9.400506E02 Y4 6.849174E02 0.000000E+00 0.000000E+00 1.027239E01 X4Y 3.590847E02 0.000000E+00 0.000000E+00 5.178501E02 X2Y3 1.676285E02 0.000000E+00 0.000000E+00 5.698284E02 Y5 1.244977E03 0.000000E+00 0.000000E+00 2.110062E01 X6 7.609826E04 0.000000E+00 0.000000E+00 1.852743E03 X4Y2 1.642005E02 0.000000E+00 0.000000E+00 5.347458E02 X2Y4 6.253616E03 0.000000E+00 0.000000E+00 2.587706E01 Y6 1.353703E03 0.000000E+00 0.000000E+00 1.608009E01 X6Y 2.568254E03 0.000000E+00 0.000000E+00 5.587846E04 X4Y3 4.755388E03 0.000000E+00 0.000000E+00 5.397733E02 X2Y5 6.793506E04 0.000000E+00 0.000000E+00 2.400347E01 Y7 1.374859E05 0.000000E+00 0.000000E+00 2.641466E01 X8 2.488086E04 0.000000E+00 0.000000E+00 5.593305E04 X6Y2 1.255585E03 0.000000E+00 0.000000E+00 6.244473E03 X4Y4 1.194473E03 0.000000E+00 0.000000E+00 1.145315E01 X2Y6 3.001214E04 0.000000E+00 0.000000E+00 8.712058E02 Y8 5.813757E05 0.000000E+00 0.000000E+00 6.570255E01 X8Y 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X6Y3 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X4Y5 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X2Y7 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 Y9 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X10 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X8Y2 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X6Y4 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X4Y6 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 X2Y8 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 Y10 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 Nradius 7.497396E+01 2.029987E+02 2.738127E+02 2.966746E+02

TABLE-US-00016 Coefficient M8 M7 M6 M5 M4 Y-decentre 0.000 116.456 154.238 192.354 412.808 X-rotation 4.164 8.327 3.019 9.973 2.768

TABLE-US-00017 Coefficient M3 M2 M1 Image plane Y-decentre 554.416 783.491 867.803 0.000 X-rotation 2.829 8.552 0.503 0.000

[0081] As can be seen from the preceding description of the embodiments, the projection optical system 9 is configured in such a way that it has an intermediate image in the two principal planes.

[0082] As can also be seen from the previous description of the embodiments, the imaging scales of the projection optical system 9, in particular of the two part lens systems 26, 27, in the direction of the two principal planes, in each case have the same sign. In particular, they both have a positive sign. Therefore no image flip occurs.

[0083] To produce a microstructured or nanostructured component, the projection exposure system 1 is used as follows: firstly, the reticle 7 and the wafer 12 are provided. A structure on the reticle 7 is then projected onto a light-sensitive layer of the wafer 12 with the aid of the projection exposure system 1. By developing the light-sensitive layer, a microstructure or nanostructure is then produced on the wafer 12 and therefore the microstructured component, for example a semiconductor component in the form of a highly integrated circuit, is produced.

[0084] During the exposure of the light-sensitive layer on the wafer 12, the latter is displaced with the aid of the wafer holder 13 in the scanning direction. In this case, the displacement takes place, in particular, synchronously with respect to a displacement of the reticle 7 with the aid of the reticle holder 8 in the scanning direction. The reduced imaging scale of the projection optical system 9 in the scanning direction can be compensated by a higher scanning speed.