CHROMATICALLY CORRECTED IMAGING ILLUMINATION OPTICAL UNIT FOR USE IN A LITHOGRAPHIC PROJECTION EXPOSURE APPARATUS

Abstract

A chromatically corrected imaging illumination optical unit serves for use in a lithographic projection exposure apparatus, for example for imaging, in a manner adapted to a downstream projection optical unit, an illumination conditioning field via an imaging beam path into an object field of the downstream projection optical unit. The illumination optical unit has at least seven and at most twelve lens elements in the imaging beam path. The illumination optical unit has an overall transmission for illumination light of at least 85%. Such an illumination optical unit can be used to improve a throughput of a projection exposure apparatus equipped therewith and achieve a high illumination quality.

Claims

1. A chromatically corrected imaging illumination optical unit configured to image an illumination conditioning field via an imaging beam path into an object field of a projection optical unit, the illumination optical unit comprising: from seven to 12 lens elements in the imaging beam path, wherein the illumination optical unit has an overall transmission for illumination light of at least 85%.

2. The illumination optical unit of claim 1, wherein, for at least three of the lens elements, the lens elements comprise aspherical lens elements.

3. The illumination optical unit of claim 1, wherein the illumination optical unit has an operating wavelength of 365 nm.

4. The illumination optical unit of claim 1, wherein the illumination optical unit is a dioptric illumination optical unit.

5. The illumination optical unit of claim 1, wherein the lens elements comprise at most three different lens-element materials.

6. The illumination optical unit of claim 1, wherein: the from seven to 12 lens elements comprise a doublet of lens elements; the doublet comprises a concave lens element fitted to a convex lens-element face of an adjacent lens element; the doublet is configured so that, for at least one coordinate region of beam path coordinates along an optical axis of the illumination optical unit, a plane which is perpendicular to the optical axis in in this coordinate region intersects both the concave lens element of the doublet and the adjacent lens element of the doublet.

7. The illumination optical unit of claim 6, wherein, for at least three of the lens elements, the lens elements comprise aspherical lens elements.

8. The illumination optical unit of claim 1, wherein: the from seven to 12 lens elements comprise a triplet of lens elements; the triplet comprises a biconcave lens fitted between two convex lens-element faces; the triplet is configured so that, for at least one coordinate region of beam path coordinates along an optical axis of the illumination optical unit, a plane which is perpendicular to the optical axis in in this coordinate region intersects both the biconcave lens element of the triplet and one of the convex lens elements of the triplet.

9. The illumination optical unit of claim 8, wherein: two separate coordinate regions of beam path coordinates are separate from one another along the optical axis of the illumination optical unit; for the two separate coordinate regions, a plane that is in the coordinate regions intersects both the biconcave lens element of the triplet and one of the convex lens elements of the triplet.

10. The illumination optical unit of claim 8, wherein, for at least three of the lens elements, the lens elements comprise aspherical lens elements.

11. The illumination optical unit of claim 1, further comprising a planar deflection mirror, wherein: a diameter of an overall beam in the imaging beam path has a constriction; the overall beam in the imaging beam path has a maximum diameter upstream of the constriction; and the illumination optical unit is configured so that, upstream of the deflection mirror, the constriction is at least 25% of the maximum diameter.

12. The illumination optical unit of claim 1, wherein the illumination optical unit has a magnifying effect at least two between the illumination conditioning field and the object field.

13. The illumination optical unit of claim 1, wherein, for at least three of the lens elements, the lens elements comprise aspherical lens elements, and the illumination optical unit has an operating wavelength of 365 nm.

14. The illumination optical unit of claim 13, wherein the illumination optical unit is a dioptric illumination optical unit.

15. The illumination optical unit of claim 14, wherein the lens elements comprise at most three different lens-element materials.

16. The illumination optical unit of claim 13, wherein the lens elements comprise at most three different lens-element materials.

17. An optical system, comprising: an illumination optical unit according to claim 1; and a projection optical unit.

18. An illumination system, comprising: an illumination optical unit according to claim 1; a light source; and an entry illumination optical unit configured to illuminate the illumination conditioning field.

19. A projection exposure apparatus, comprising: a light source; an illumination optical unit according to claim 1; an entry illumination optical unit configured to illuminate the illumination conditioning field; and a projection optical unit configured to image the object field into an image field.

20. A method of using a projection exposure apparatus comprising an illumination system and a projection optical unit, the method comprising: using the illumination optical unit to illuminate an object field of the projection optical unit; and using the projection optical unit to image the object field into an image field of the projection optical unit, wherein the illumination system comprises an illumination optical unit according to claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Exemplary embodiments of the disclosure are explained in greater detail below with reference to the drawing, in which:

[0022] FIG. 1 schematically shows a meridional section through optical main groups of a microlithographic projection exposure apparatus;

[0023] FIG. 2 shows a meridional section through a chromatically corrected imaging illumination optical unit for use in the projection exposure apparatus; and

[0024] FIGS. 3 to 6 each show illustrations similar to FIG. 2 of further embodiments of a chromatically corrected imaging illumination optical unit for use in the projection exposure apparatus.

DETAILED DESCRIPTION

[0025] A projection exposure apparatus 1 is illustrated schematically in meridional section in FIG. 1 as regards its optical main groups. This schematic illustration shows the optical main groups as refractive optical elements. The optical main groups may just as well also be in the form of diffractive or reflective components or combinations or sub-combinations of refractive/diffractive/reflective assemblies of optical elements.

[0026] In order to facilitate the illustration of positional relationships, an xyz coordinate system will be used below. In FIG. 1, the x axis extends into the plane of the drawing perpendicularly in relation thereto. The y axis extends upwards in FIG. 1. In FIG. 1, the y axis extends to the right and parallel to an optical axis 2 of the projection exposure apparatus 1. This optical axis 2 may optionally also be folded multiple times.

[0027] The projection exposure apparatus 1 has a radiation source 3, which generates used light in the form of an illumination or imaging beam 4. The used light 4 has a wavelength in the deep ultraviolet (DUV) range, for example in the range between 100 nm and 200 nm, or in the ultraviolet (UV) range between 200 nm and 400 nm. As an alternative, the used light 4 may also have a wavelength in the extreme ultraviolet (EUV) range, for example between 5 nm and 30 nm. Exemplary wavelengths of the beam source 3 are 365 nm, 248 nm or 193 nm. Depending on the radiation source 3 used, a used wavelength spectrum utilized is narrowband, but can also have a greater broadband capacity, for example if an Hg discharge lamp is utilized.

[0028] An illumination optical unit 5 of the projection exposure apparatus 1 guides the used light 4 from the radiation source 3 to an object plane 6 of the projection exposure apparatus 1. An object, which is in the form of a reticle 7 and is to be imaged by the projection exposure apparatus 1, is arranged in the object plane 6. The reticle 7 is illustrated in dashed line in FIG. 1. The reticle 7 is carried by a holder, which is not illustrated, which enables a controlled scan displacement or step-by-step displacement.

[0029] As first optical main group, the illumination optical unit 5 firstly comprises a pupil shaping optical unit 8. This serves to generate a defined intensity distribution of the used light 4 in a downstream pupil plane 9. The pupil shaping optical unit 8 moreover serves as setting device for presetting various illumination settings. Corresponding setting devices that have, for example, adjustable optical components or interchangeable stops are known to those skilled in the art. The pupil shaping optical unit 8 forms the radiation source 3 in a plurality of secondary light sources in the pupil plane 9. The pupil shaping optical unit 8 may additionally also have a field-shaping function. Facet elements, honeycomb elements and/or diffractive optical elements can be used in the pupil shaping optical unit 8. The pupil plane 9 is optically conjugate to a further pupil plane 10 of a projection lens 11 of the projection exposure apparatus 1. The projection lens 11 is arranged downstream of the illumination optical unit 5 between the object plane 6 and an image plane 12. A wafer 13 is arranged in the image plane 12 and illustrated in dashed line in FIG. 1. The wafer 13 is carried by a holder, which is not illustrated, which enables a controlled scan displacement or step-by-step displacement. An object field 14 in the object plane 6 is imaged into an image field 14a in the image plane 12 by the projection lens 11.

[0030] A field lens-element group 15 as further optical main group of the illumination optical unit 5 is downstream of the pupil plane 9 arranged behind the pupil shaping optical unit 8. An intermediate image plane 16, which is conjugate to the object plane 6, is arranged behind the field lens-element group 15. The field lens-element group 15 is therefore a condenser group. A stop 17 for presetting a peripheral boundary of the object field 14 is in the intermediate image plane 16. The stop 17 is also referred to as REMA stop (reticle masking system for stopping down the reticle 7).

[0031] The intermediate image plane 16 is imaged into the object plane 6 by a lens group 18, which is also referred to as REMA lens-element group or REMA lens. The lens group 18 constitutes a further optical main group of the illumination optical unit 5. The lens group 18 is a chromatically corrected imaging illumination optical unit.

[0032] A further pupil plane 19 is between the field planes 16 and 6.

[0033] FIG. 2 shows a meridional section through an embodiment of an imaging illumination optical unit 20, which can be used instead of the lens group 18 as REMA lens in the projection exposure apparatus 1.

[0034] The illumination optical unit 20 serves to image, in a manner adapted to the downstream projection optical unit 11, an illumination conditioning field 16a in the intermediate image plane 16, preset by the stop 7, into the object field 14 of the downstream projection optical unit 11.

[0035] FIG. 2 illustrates the course of a respective main beam 21 and peripheral, pupil-delimiting beams 22, which start from two mutually spaced field points. This depicts an imaging beam path of the illumination light 4.

[0036] The illumination optical unit 20 has a total of nine lens elements L1 to L9, which are numbered in the order in which they are impinged upon in the imaging beam path 23, in the imaging beam path 23 between the illumination conditioning field 16a and the object field 14.

[0037] The lens elements L1 and L2 form a condenser lens-element group of the illumination optical unit 20 in the vicinity of the conditioning field 16a. The lens elements of this condenser lens-element group of the illumination optical unit 20 are made of the same lens-element material.

[0038] The lens elements L3 to L6 form a lens-element group, close to the pupil, of the illumination optical unit 20 in the vicinity of the pupil plane 19.

[0039] The lens elements L7 to L9 form a field lens-element group of the illumination optical unit 20 in the vicinity of the object field 14.

[0040] In front of the object field 14, a graduated filter F of the illumination optical unit 20 is downstream of the lens element L9. The graduated filter F is a static neutral density filter with an absorbent layer. The graduated filter F ensures homogeneity of the intensity of an illumination of the object field 14 or the image field 14a.

[0041] The illumination optical unit 20 has an overall transmission for the illumination light 4 of at least 90.0%.

[0042] The illumination optical unit 20 is designed for illumination light 4 with a wavelength of 365 nm.

[0043] The illumination optical unit 20 has a dioptric design, that is does not have a mirror with a beam-influencing effect. In the embodiment illustrated, the illumination optical unit 20 actually also does not have a planar deflection mirror. There is space for such a planar deflection mirror between the lenses L6 and L7, with the result that, in a further embodiment of the illumination optical unit comprising such a planar deflection mirror, the imaging beam path 23 may be folded.

[0044] The lens elements L3 to L5 form a triplet 24. The lens element L4 of the triplet that is in between them has a biconcave design and is fitted between two convex lens-element faces of the respective adjacent lens elements L3 and L5 of the triplet. This matching is such that, for coordinate regions za, zb of beam path coordinates along the optical axis 2 of the illumination optical unit 20, it holds true that a plane (the respective xy planes at the region boundaries za, zb are illustrated in dashed line in FIG. 2) which is perpendicular to the optical axis 2 in the respective coordinate region za, zb intersects both the biconcave lens element L4 and one of the adjacent lens elements L3, L5 of the triplet 24. The two coordinate regions za, in which the lens elements L4 and L3 are intersected, and zb, in which the lens elements L4 and L5 and intersected, are separate from one another along the optical axis 2, and are thus spaced from one another along the optical axis 2. The coordinate regions za, zb have an extent along the optical axis 2 in the range between 1 mm and 50 mm, for example in the range between 5 mm and 25 mm. The extent of the coordinate region za is in the region of 20 mm. The extent of the coordinate region zb is in the region of 5 mm.

[0045] The illumination optical unit 20 provides magnification by a factor of 4 between the conditioning field 16a and the object field 14.

[0046] The object field 14 has a diameter which is corrected in terms of imaging aberrations of approximately 120 mm. This diameter, corrected in terms of imaging aberrations, of the object field 14 is greater than 10 mm, greater than 25 mm, greater than 50 mm and greater than 100 mm.

[0047] A spacing between the intermediate image plane 16 and the object plane 6 is 1200 mm.

[0048] The lens elements L1, L2, L3, L5, L6, L7 and L8 are made of a crown glass (FK5) with a refractive index in the region of 1.50 at the illumination light wavelength. The lens elements L4 and L9 are made of a flint glass (LLF1) with a refractive index in the region of 1.58 at the illumination light wavelength. The lens elements L1 to L9 of the illumination optical unit 20 are made of exactly two different lens-element materials, specifically on the one hand the crown glass and on the other hand the flint glass.

[0049] The following tables show design data for the illumination optical unit 20 according to FIG. 2.

[0050] In the first column, the first table for FIG. 2 shows optical faces of the illumination optical unit, which are numbered from left to right.

[0051] Faces 1 and 2 constitute the intermediate image plane 16.

[0052] Faces 3 and 4 describe the entry and exit faces of the lens element L1.

[0053] Faces 5 and 6 describe the entry and exit faces of the lens element L2. The exit surface of the lens element L2 is in the form of an asphere, the asphere coefficients of which are tabulated according to the following asphere formula:

[00001]$p\left(h\right)=\left[\left(\left(1/r\right)h^2\right)/(1+\mathrm{SQRT}(1-\left(1+K\right){\left(1/r\right)}^2{h}^2\left)\right)\right]+C1.Math.h^4+C2.Math.h^6+.Math.$

in Table 2 for FIG. 2.

[0054] Faces 7 and 8 describe the entry and exit faces of the lens element L3.

[0055] Faces 9 and 10 describe the entry and exit faces of the lens element L4.

[0056] Faces 11 and 12 describe the entry and exit faces of the lens element L5. The entry face of the lens element L5 in turn is in the form of an asphere, the asphere coefficients of which are tabulated in Table 3 for FIG. 2.

[0057] Face 13 describes an arrangement plane for a pupil stop, that is the position of the pupil plane 19. In the illumination optical unit 20, the pupil plane 19 is between the lens elements L5 and L6.

[0058] Faces 14 and 15 describe the entry and exit faces of the lens element L6. The exit face of the lens element L6 in turn is in the form of an asphere, the asphere coefficients of which are tabulated in Table 4 for FIG. 2.

[0059] Face 16 describes a possible arrangement position of a planar deflection mirror, which is not illustrated in FIG. 2.

[0060] Faces 17 and 18 describe an entry and an exit face of the lens element L7. The entry face of the lens element L7 in turn is in the form of an asphere, the asphere coefficients of which are tabulated in Table 5 for FIG. 2.

[0061] Faces 19 and 20 describe the entry and exit faces of the lens element L8.

[0062] Faces 21 and 22 describe the entry and exit faces of the lens element L9. The exit face of the lens element L9 in turn is in the form of an asphere, the asphere coefficients of which are tabulated in Table 6 for FIG. 2.

[0063] Faces 23 and 24 describe the entry and exit faces of the graduated filter F, which is likewise made of crown glass.

[0064] Faces 25 and 26 describe an entry and an exit face of the reticle 7 with a substrate of quartz glass (Suprasil).

[0065] The lens elements L1 to L9 are rotationally symmetrical about the optical axis 2. A total of five of the nine lens elements are in the form of aspherical lens elements. In each of these five aspherical lens elements, in each case only exactly one of the two optical faces is in the form of an asphere, wherein the other one of the two optical faces of the respective lens element is in the form of a spherical face.

[0066] The illumination optical unit 20 does not have an intermediate image plane.

TABLE-US-00001 Table 1 for FIG. 2 REFRACTIVE INDEX FACE RADII THICKNESS GLASSES 365.5 nm SEMIDIAMETER 1 0.000000 0.0000 1.000000 15.201 2 0.000000 33.4083 1.000000 15.201 3 47.154742 51.0868 FK5 1.503934 31.332 4 62.097291 0.7001 1.000000 54.983 5 876.892861 29.6831 FK5 1.503934 72.111 6 112.260533 Asphere 158.6215 1.000000 73.358 7 809.022117 36.2291 FK5 1.503934 98.562 8 205.492719 6.6463 1.000000 98.796 9 175.852713 4.0076 LLF1 1.579164 98.387 10 324.841427 7.5996 1.000000 104.559 11 2308.992575 Asphere 49.2279 FK5 1.503934 104.853 12 179.202113 7.0159 1.000000 105.547 13 0.000000 Stop 44.3644 1.000000 100.762 14 190.277871 16.1436 FK5 1.503934 100.191 15 628.632679 Asphere 305.2560 1.000000 99.241 16 0.000000 Deflection 192.6634 1.000000 129.593 mirror 17 117.275396 Asphere 16.5329 FK5 1.503934 88.809 18 148.250792 91.1074 1.000000 87.182 19 479.413957 5.0241 FK5 1.503934 75.558 20 133.042920 45.5140 1.000000 72.187 21 1864.406648 18.8771 LLF1 1.579164 73.922 22 209.649304 Asphere 16.2712 1.000000 74.063 23 0.000000 4.0000 FK5 1.503934 69.906 24 0.000000 55.7500 1.000000 69.523 25 0.000000 6.2500 SUPRASIL 1.474471 61.504 26 0.000000 0.0000 1.000000 61.069

TABLE-US-00002 Table 2 for FIG. 2 FACE 6 K 0.0000000000 C1 1.3978383887e07 C2 8.4361042350e12 C3 4.1031031362e16 C4 7.1049614540e20 C5 5.0420939318e24 C6 4.7838361500e28

TABLE-US-00003 Table 3 for FIG. 2 FACE 11 K 0.0000000000 C1 1.7029932647e07 C2 7.3936840682e12 C3 1.3245249758e16 C4 1.2442350080e22

TABLE-US-00004 Table 4 for FIG. 2 FACE 15 K 0.0000000000.sup. C1 9.8483547350e08 C2 1.5043660294e12 C3 1.6440078913e16 C4 2.7643515570e21

TABLE-US-00005 Table 5 for FIG. 2 FACE 17 K 0.0000000000.sup. C1 4.9297281500e09 C2 1.6147772848e12 C3 1.3012799782e16 C4 1.9716901478e20

TABLE-US-00006 Table 6 for FIG. 2 FACE 22 K 0.0000000000.sup. C1 3.7448322936e08 C2 7.5270730209e13 C3 2.2674144098e16 C4 2.2453178888e20

[0067] With reference to FIG. 3, a description is given below of a further embodiment of an illumination optical unit 25, which can be used instead of the illumination optical unit 20 as REMA lens in the projection exposure apparatus 1. Components and functions that correspond to those which were already explained above with reference to FIGS. 1 and 2 and for example with reference to FIG. 2 have the same reference signs and are not discussed in detail again.

[0068] The illumination optical unit 25 has a total of ten lens elements L1 to L10. The graduated filter F in turn is arranged between the last lens element L10 in the imaging beam path 23 and the reticle 7.

[0069] The illumination optical unit 25 has an overall transmission of 90.0%.

[0070] The lens elements L1, L5 and L10 are made of flint glass (LLF1) and the other lens elements L2 to L4 and L6 to L9 are made of crown glass (FK5).

[0071] The lens elements L1 to L3 form a condenser lens-element group of the illumination optical unit 25 in the vicinity of the conditioning field 16a.

[0072] The lens elements L4 to L8 form a lens-element group, close to the pupil, of the illumination optical unit 25 in the vicinity of the pupil plane 19.

[0073] The lens elements L9 and L10 form a field lens-element group in the vicinity of the object field 14.

[0074] The lens elements L4 and L5 form a doublet 24a of lens elements. The concave lens element L5 is fitted to an adjacent, convex lens-element face of the lens element L4 of the doublet such that, for a coordinate region za, it holds true in turn that, along the optical axis 2 of the illumination optical unit 25, a plane which is perpendicular to the optical axis 2 in this coordinate region za intersects both the concave lens element L5 and the adjacent lens element L4 of the doublet.

[0075] In the illumination optical unit 25, there are also two different lens-element materials in the case of the condenser lens-element group L1 to L3.

[0076] The optical design data of the illumination optical unit 25 are provided by the following design tables, which correspond to the tables for FIG. 2 in terms of the structure.

[0077] The exit face of the lens element L1, the entry face of the lens element L6, the entry face of the lens element L9 and the exit face of the lens element L10 are in the form of aspheres, the asphere coefficients of which are tabulated in Tables 2 to 5 for FIG. 3.

[0078] In turn, there is space between the lens elements L8 and L9 for a planar deflection mirror, which is reported in Table 1 for FIG. 3 as face 20 by way of example.

[0079] In Table 1 for FIG. 3, the pupil plane 19 in which a pupil stop may be arranged is reported as face 15. In the illumination optical unit 25, the pupil plane 19 is between the lens elements L6 and L7.

[0080] Faces 27 and 28 in turn stand for the position of the entry and exit faces of the reticle 7.

TABLE-US-00007 Table 1 for FIG. 3 REFRACTIVE INDEX FACE RADII THICKNESS GLASSES 365.5 nm SEMIDIAMETER 1 0.000000 0.0000 1.000000 15.201 2 0.000000 35.6883 1.000000 15.201 3 41.097725 8.8707 LLF1 1.579164 31.204 4 118.007859 Asphere 4.9369 1.000000 45.674 5 137.731947 32.0440 FK5 1.503934 49.995 6 55.786142 0.7485 1.000000 53.048 7 648.268979 34.6741 FK5 1.503934 79.912 8 142.005608 145.2147 1.000000 81.222 9 199.149325 54.4084 FK5 1.503934 109.266 10 357.016155 11.2046 1.000000 108.647 11 255.357547 4.9967 LLF1 1.579164 106.746 12 221.305131 36.1303 1.000000 104.215 13 1604.088294 Asphere 32.9565 FK5 1.503934 105.609 14 186.905406 5.9988 1.000000 106.481 15 0.000000 Stop 6.5359 1.000000 106.154 16 10466.860203 23.3759 FK5 1.503934 106.305 17 296.911961 61.6428 1.000000 106.414 18 139.443538 10.9760 FK5 1.503934 97.622 19 126.257130 239.7948 1.000000 93.397 20 0.000000 Deflection 223.0600 1.000000 124.121 mirror 21 115.871602 Asphere 14.0477 FK5 1.503934 84.379 22 123.701378 135.4840 1.000000 81.678 23 128.784421 12.4614 LLF1 1.579164 72.400 24 99.845257 Asphere 1.0600 1.000000 73.740 25 0.000000 4.0000 FK5 1.503934 69.751 26 0.000000 55.7500 1.000000 69.375 27 0.000000 6.2500 SUPRASIL 1.474471 61.465 28 0.000000 0.0000 1.000000 61.050

TABLE-US-00008 Table 2 for FIG. 3 FACE 4 K 0.0000000000 C1 7.6247709121e07 C2 1.2104026966e10 C3 9.2330200600e16 C4 2.2219538098e18

TABLE-US-00009 Table 3 for FIG. 3 FACE 13 K 0.0000000000.sup. C1 1.7508188699e08 C2 1.0257377630e12 C3 7.8552731406e17 C4 4.4209555397e21

TABLE-US-00010 Table 4 for FIG. 3 FACE 21 K 0.0000000000.sup. C1 3.6248868257e09 C2 3.2786024086e12 C3 4.7412545643e16 C4 4.0596735709e20

TABLE-US-00011 Table 5 for FIG. 3 FACE 24 K 0.0000000000 C1 1.5385855888e07 C2 1.6159747582e12 C3 1.0316186680e15 C4 7.0634719992e20

[0081] With reference to FIG. 4, a description is given below of a further embodiment of an illumination optical unit 26, which can be used instead of the illumination optical unit 20 as REMA lens in the projection exposure apparatus 1. Components and functions that correspond to those which were already explained above with reference to FIGS. 1 to 3 and for example with reference to FIGS. 2 and 3 have the same reference signs and are not discussed in detail again.

[0082] The illumination optical unit 26 has a total of eleven lens elements L1 to L11. A planar deflection mirror M, which deflects a main beam 212 of a central field point by 90, is arranged between the lens elements L9 and L10.

[0083] The lens elements L1 to L3 form a condenser lens-element group of the illumination optical unit 26. The lens elements L7 to L9 form a lens-element group, close to the pupil, of the illumination optical unit 26. The pupil plane 19 lies directly in front of the lens element L7 in the imaging beam path.

[0084] Between these lens-element groups is the lens-element group comprising the lens elements L4 to L6, which in turn form a lens-element triplet comprising a biconcave lens element L5, which is fitted between the two convex lens elements L4 and L6 such that in turn sectional coordinate regions za, zb are produced in accordance with what was explained above in connection with FIG. 2.

[0085] The lens elements L1, L5, L7, L10 and L11 are made of flint glass (LLF1). The lens elements L2 to L4, L6, L8 and L9 are made of crown glass (FK5).

[0086] The illumination optical unit 26 has an overall transmission of 88.5%.

[0087] The following tables show design data for the illumination optical unit 26 according to FIG. 4.

[0088] The exit face of the lens element L1, the entry face of the lens element L7 and the exit face of the lens element L11 are in the form of asphere faces, the coefficients of which are tabulated in Tables 2 to 4 for FIG. 4.

[0089] In Table 1 for FIG. 4, face 15 depicts the pupil plane 19.

[0090] Face 22 depicts the arrangement plane for the mirror M.

[0091] Faces 29 and 30 depict the entry and exit faces of the reticle 7.

TABLE-US-00012 Table 1 for FIG. 4 REFRACTIVE INDEX FACE RADII THICKNESS GLASSES 365.5 nm SEMIDIAMETER 1 0.000000 0.0000 1.000000 15.201 2 0.000000 39.6612 1.000000 15.201 3 43.071133 9.1371 LLF1 1.579164 33.297 4 88.951126 Asphere 2.3185 1.000000 46.363 5 116.219867 42.7434 FK5 1.503934 49.117 6 70.238530 2.1371 1.000000 63.172 7 854.234003 45.6153 FK5 1.503934 88.609 8 118.542375 11.2220 1.000000 91.702 9 234.258950 47.4958 FK5 1.503934 104.225 10 349.966089 15.5215 1.000000 103.745 11 240.812724 3.9999 LLF1 1.579164 101.288 12 277.473259 4.9354 1.000000 101.872 13 236.200610 46.7367 FK5 1.503934 104.595 14 369.931026 125.7620 1.000000 104.579 15 0.000000 Stop 21.6899 1.000000 82.459 16 263.068566 Asphere 3.9999 LLF1 1.579164 82.680 17 332.085484 18.1816 1.000000 87.709 18 5724.848529 31.9457 FK5 1.503934 91.195 19 187.253944 9.9824 1.000000 93.120 20 701.592695 25.6467 FK5 1.503934 100.393 21 403.436133 241.2678 1.000000 100.753 22 0.000000 Deflection 223.9282 1.000000 134.956 mirror 23 111.542494 13.1686 LLF1 1.579164 83.449 24 113.935870 133.3578 1.000000 80.138 25 126.352882 13.8645 LLF1 1.579164 72.773 26 99.448893 Asphere 1.6808 1.000000 74.418 27 0.000000 4.0000 FK5 1.503934 70.059 28 0.000000 55.7500 1.000000 69.675 29 0.000000 6.2500 SUPRASIL 1.474471 61.570 30 0.000000 0.0000 1.000000 61.009

TABLE-US-00013 Table 2 for FIG. 4 FACE 4 K 0.0000000000 C1 5.1566837293e07 C2 2.3571855613e11 C3 2.8478120846e15 C4 1.7657237108e18

TABLE-US-00014 Table 3 for FIG. 4 FACE 16 K 0.0000000000.sup. C1 1.9858154496e08 C2 3.8868489920e13 C3 1.3698417265e17 C4 4.0008110314e21

TABLE-US-00015 Table 4 for FIG. 4 FACE 26 K 0.0000000000 C1 1.3082537358e07 C2 2.7157620429e12 C3 1.9063364805e16 C4 9.2120975249e20 C5 1.4353799155e24

[0092] With reference to FIG. 5, a description is given below of a further embodiment of an illumination optical unit 27, which can be used instead of the illumination optical unit 20 as REMA lens in the projection exposure apparatus 1. Components and functions that correspond to those which were already explained above with reference to FIGS. 1 to 4 and for example with reference to FIGS. 2 and 4 have the same reference signs and are not discussed in detail again.

[0093] The illumination optical unit 27 has a total of eleven lens elements L1 to L11.

[0094] The lens elements L1 to L3 form a condenser lens-element group. The lens elements L4 to L9 form a lens-element group close to the pupil. The lens elements L10 and L11 form a field lens-element group.

[0095] The lens element L1 is made of quartz glass (SILUV) with high UV transmission. The lens elements L2 to L4, L7, L9 and L11 are made of crown glass (FK5). The lens elements L5, L6, L8 and L10 are made of flint glass (LLF1).

[0096] Overall, the lens elements L1 to L11 of the illumination optical unit 27 are thus made of three different materials.

[0097] The 90-deflection mirror M is arranged between the lens elements L9 and L10.

[0098] The illumination optical unit 27 has an overall transmission of 88.1%.

[0099] The following tables show design data for the illumination optical unit 27 according to FIG. 5.

[0100] The quartz glass material of the lens element L1 has a refractive index of approximately 1.47 at the illumination light wavelength.

[0101] The entry face of the lens element L2, the entry face of the lens element L9 and the exit face of the lens element L11 are in the form of asphere faces, the coefficients of which are shown in Tables 2 to 4 for FIG. 5.

[0102] In Table 1, face 17 stands for the pupil plane 19.

[0103] In Table 1, face 22 stands for the 90-deflection mirror M.

[0104] Faces 29 and 30 stand for the entry and exit faces of the reticle 7.

[0105] The lens elements L8 and L8 in turn form a doublet with a sectional plane coordinate region za in accordance with what was explained above in connection for example with FIG. 3.

TABLE-US-00016 Table 1 for FIG. 5 REFRACTIVE INDEX FACE RADII THICKNESS GLASSES 365.5 nm SEMIDIAMETER 1 0.000000 0.0000 1.000000 15.201 2 0.000000 38.8180 1.000000 15.201 3 46.375081 56.3097 SILUV 1.474477 33.592 4 74.602835 0.7000 1.000000 63.383 5 1141.672413 Asphere 39.5814 FK5 1.503934 84.639 6 145.202607 4.1963 1.000000 88.561 7 380.453883 38.8368 FK5 1.503934 99.938 8 282.847134 2.2902 1.000000 100.352 9 149.973132 46.9288 FK5 1.503934 94.633 10 733.141506 1.8070 1.000000 92.226 11 673.610864 4.0328 LLF1 1.579164 91.332 12 120.982433 60.9935 1.000000 79.640 13 193.923271 4.0000 LLF1 1.579164 79.770 14 364.831429 19.5968 1.000000 84.989 15 398.915248 51.2054 FK5 1.503934 94.535 16 161.054049 1.7799 1.000000 96.049 17 0.000000 Stop 30.7228 1.000000 93.419 18 2169.967720 4.0003 LLF1 1.579164 96.107 19 248.107525 14.6242 1.000000 96.907 20 322.053027 Asphere 47.2360 FK5 1.503934 100.007 21 248.013400 282.3400 1.000000 101.457 22 0.000000 Deflection 288.3692 1.000000 133.805 mirror 23 109.991352 25.4853 LLF1 1.579164 80.943 24 98.944234 53.1787 1.000000 72.756 25 233.964190 16.7496 FK5 1.503934 72.429 26 127.917172 Asphere 2.2172 1.000000 73.120 27 0.000000 4.0000 FK5 1.503934 69.863 28 0.000000 55.7500 1.000000 69.479 29 0.000000 6.2500 SUPRASIL 1.474471 61.386 30 0.000000 0.0000 1.000000 60.931

TABLE-US-00017 Table 2 for FIG. 5 FACE 5 K 0.0000000000.sup. C1 7.9924337006e08 C2 2.7057877824e12 C3 1.6496548992e16 C4 2.0725249710e21

TABLE-US-00018 Table 3 for FIG. 5 FACE 20 K 0.0000000000.sup. C1 2.0443114072e08 C2 2.0775994625e13 C3 8.8606230113e18 C4 1.0981504658e21

TABLE-US-00019 Table 4 for FIG. 5 FACE 26 K 0.0000000000 C1 9.1402583991e08 C2 6.2127922914e13 C3 1.8883297185e16 C4 4.4093426130e20

[0106] With reference to FIG. 6, a description is given below of a further embodiment of an illumination optical unit 28, which can be used instead of the illumination optical unit 20 as REMA lens in the projection exposure apparatus 1. Components and functions that correspond to those which were already explained above with reference to FIGS. 1 to 5 and for example with reference to FIGS. 2 and 5 have the same reference signs and are not discussed in detail again.

[0107] The illumination optical unit 28 has a total of eleven lens elements L1 to L11.

[0108] The lens elements L1 to L5 form a condenser lens-element group. The lens elements L7 to L9 form a lens-element group close to the pupil. The lens elements L10 and L11 form a field lens-element group. The lens elements L3 to L5 in turn form a lens-element triplet with two sectional plane coordinate regions za, zb in accordance with what was explained above in connection for example with FIG. 2.

[0109] The lens elements L1 to L3, L5, L7, L8, L10 and L11 are made of quartz glass (SILUV) with high UV transmission. The lens elements L4, L6 and L9 are made of flint glass (LLF1). The lens elements L1 to L11 of the illumination optical unit 28 are thus made of two different lens-element materials.

[0110] The illumination optical unit 28 has an overall transmission of 91.4%.

[0111] The pupil plane 19 is between the lenses L7 and L8, which form a quartz-glass doublet. In combination therewith, the following lens element L9 constitutes a constriction lens-element group in front of the deflection mirror M, which leads to a constriction of a diameter of an overall beam in the imaging beam path 22 compared to a maximum diameter of the overall beam in the imaging beam path 22 in front of the constriction of at least 25%. In the illumination optical unit 28, the maximum constriction of the overall beam is at the exit face of the lens element L9, where a constriction of approximately 27% takes place compared to the maximum diameter of the overall beam present in the region of the pupil plane 19. This constriction of the overall beam reduces size issues for the deflection mirror M.

[0112] The following tables show design data for the illumination optical unit 28 according to FIG. 6.

[0113] An exit face of the lens element L2, an exit face of the lens element L8 and an exit face of the lens element L10 are in the form of asphere faces, the coefficients of which are shown in Tables 2 to 4 for FIG. 6.

[0114] The deflection mirror M is between the lens elements L9 and L10.

TABLE-US-00020 Table 1 for FIG. 6 REFRACTIVE INDEX FACE RADII THICKNESS GLASSES 365.5 nm SEMIDIAMETER 1 0.000000 0.0000 1.000000 15.201 2 0.000000 43.3000 1.000000 15.201 3 43.439583 50.6500 SILUV 1.474477 34.698 4 68.925441 4.1800 1.000000 61.674 5 570.575000 50.4400 SILUV 1.474477 91.604 6 136.558125 Asphere 2.0500 1.000000 95.483 7 293.599500 59.0000 SILUV 1.474477 106.299 8 225.232600 3.6200 1.000000 106.392 9 267.466900 5.7800 LLF1 1.579164 103.860 10 250.184200 6.2200 1.000000 103.752 11 228.857800 56.1500 SILUV 1.474477 106.663 12 291.355700 63.9500 1.000000 106.711 13 205.344500 5.4700 LLF1 1.579164 95.212 14 294.275900 20.9400 1.000000 98.806 15 433.867600 54.2600 SILUV 1.474477 105.066 16 194.232400 7.8000 1.000000 106.506 17 0.000000 Stop 2.2200 1.000000 103.237 18 179.716800 63.3800 SILUV 1.474477 105.714 19 238.439675 Asphere 36.2200 1.000000 103.396 20 1158.100000 8.8600 LLF1 1.579164 81.725 21 110.597400 205.5100 1.000000 72.804 22 0.000000 Deflection 264.5200 1.000000 110.237 mirror 23 307.278600 38.9300 SILUV 1.474477 94.832 24 132.613643 Asphere 0.7000 1.000000 97.331 25 108.183907 39.3800 SILUV 1.474477 85.514 26 89.225488 42.4700 1.000000 70.847 27 0.000000 4.0000 FK5 1.503934 69.760 28 0.000000 55.7500 1.000000 69.376 29 0.000000 6.2500 SUPRASIL 1.474471 61.373 30 0.000000 0.0000 1.000000 60.932

TABLE-US-00021 Table 2 for FIG. 6 FACE 6 K 0.0000000000 C1 6.4767751917e08 C2 3.8078941721e12 C3 3.9431936776e17 C4 1.1931539193e20

TABLE-US-00022 Table 3 for FIG. 6 FACE 19 K 0.0000000000.sup. C1 8.1625981689e08 C2 2.2003555065e12 C3 1.0316433801e16 C4 2.6855291221e21

TABLE-US-00023 Table 4 for FIG. 6 FACE 24 K 0.0000000000 C1 5.4334222401e08 C2 1.4089970606e12 C3 1.1687952948e17 C4 7.1987388333e21

[0115] An tendue of the illumination optical unit described above is 820 mm.sup.2sr. Depending on the embodiment of the illumination optical unit, the tendue may also have another value in the range between 700 mm.sup.2sr and 1200 mm.sup.2sr, for example. 750 mm.sup.2sr, 950 mm.sup.2sr or 1000 mm.sup.2sr.

[0116] A point image quality is at a spot diameter of less than 400 m. To ascertain the point image quality, a generated point image is measured by way of an energy distribution of an imaging light sub-beam proceeding from the associated object point. A diameter of the point image is defined by the fact that 99.9% of the measured light power of the imaging light sub-bundle is within a point image circle with the diameter of the respective point image quality, that is in the present case within a circle with a diameter of less than 400 m. A centre point of the respective circle is a point at which a respective main beam that proceeds from the assigned object point passes through the image plane 12 at the reference wavelength, in the present case at 365.5 nm.

[0117] Using the projection exposure apparatus 1, at least one part of the reticle 7 is imaged onto a region of a light-sensitive layer on the wafer 13 for the lithographic production of a micro-or nanostructured component. Depending on whether the projection exposure apparatus 1 is in the form of a scanner or a stepper, the reticle 7 and the wafer 13 are moved in a temporally synchronized manner in the y direction continuously in scanner operation or step by step in stepper operation.