# Patent

## Title
Projection objective for microlithography

## Abstract

The invention relates to a projection lens comprising a lens assembly that has at least one first narrowing of the group of light beams. A lens with a non-spherical surface is located in front of and/or behind the first narrowing.

## Background
CROSS REFERENCES TO RELATED APPLICATIONS
This application is a continuation application of U.S. Pat. No. 6,801,364, which issued Oct. 5, 2004.
U.S. Pat. 6,349,005 B1, and 6,522,484 B1 and 6,683,729, in which the Applicant participated, are incorporated herein by reference.


STATEMENT REGARDING FEDERAL SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable.
REFERENCE TO A MICROFICHE APPENDIX
Not Applicable.
BACKGROUND OF THE INVENTION
1. Technical Field
The invention relates to a projection objective with a lens arrangement, which can be divided into six lens groups. The first, third, fifth and sixth lens groups have positive power and the second and fourth lens groups respectively have negative power. The division of the lens system into lens groups is described in more detail hereinafter, based on the direction of propagation of the radiation.
The first lens group is positive and ends with a lens of positive power. A bulge is formed by the first lens group; it is unimportant if negative lenses are also arranged in the bulge.
The second lens group is of negative total power. This second lens group has as its first lens a lens having a concave lens surface toward the image. This second lens group substantially describes a waist. Here, also it is not of substantial importance if a few positive lenses are included in the second lens group, as long as the waist is maintained.
The third lens group begins with a lens having positive power and a convex lens surface on the image side, and which can be a meniscus. If a thick meniscus lens is provided as the first lens, the separation of the lens groups can be considered to be within the lens.
The fourth lens group is of negative power. This fourth lens group begins with a lens of negative power, followed by several lenses having negative power. A waist is formed by this lens group. It is unimportant if lenses having positive power are also contained within this lens group, as long as these influence the course of the beam over only a short distance and thus the waisted shape of the fourth lens group is maintained.
The fifth lens group has positive power overall. The first lens of this fifth lens group has a convex lens surface on the image side. A bulge is formed by the fifth lens group.
After the lens of maximum diameter (the bulge), there follow at least an additional two positive lenses in the fifth lens group, further negative lenses also being permitted.
The sixth lens group is likewise positive in its total power. The first lens of the sixth lens group is negative and has on the image side a concave lens surface. This first lens of the sixth lens group has a considerably smaller diameter in comparison with the maximum diameter of the bulge.
2. Background Art
Such projection objectives are in particular used in microlithography. They are known, for example, from the German Applications DE 198 55 108A, DE 198 55 157A, and DE 198 55 158A, in which the Applicant participated, and from the state of the art cited therein. These documents are incorporated herein by reference.
These projection objectives are usually constructed from purely spherical lenses, since the production and testing technology is advantageous for spheres.
Projection objectives are known from German Application DE 198 18 444 A1 which have lenses having aspheric surfaces in at least the fourth or fifth lens group. An increase of the numerical aperture and of the image quality can be attained by means of the aspheric surfaces. The projection objectives shown have a length from the mask plane to the image plane of 1,200 mm to 1,500 mm. A considerable use of material is associated with this length. High production costs are entailed by this use of material, since because of the required high image quality only high quality materials can be used. Aspheric lenses up to a diameter of about 300-mm are required, the provision of which is particularly expensive. It is not at all clear in the technical world whether aspheric lenses with such large lens diameters can be provided in the required quality. “Aspheric surfaces” are understood to include all surfaces which are not spherical and which are rotationally symmetrical. Rotationally symmetrical splines can also be considered as aspheric lens surfaces.
SUMMARY OF THE INVENTION
The invention has as its object to provide a projection objective which has as few lenses as possible, with reduced use of material, the aspheric lens surfaces used being as few and as small as possible, with the lowest possible asphericity. A high aperture projection objective of short structure is to be cost-efficiently provided in this way.
The object of the invention is attained in particular by a projection objective for microlithography having a lens arrangement comprising a first lens group having positive power; a second lens group having negative power; a third lens group having positive power; a fourth lens group having negative power; a fifth lens group having positive power; and a sixth lens group having positive power; wherein a lens at the end of the second lens group, particularly the last lens of the second lens group, or a lens at the beginning of the third lens group, particularly the first lens of the third lens group, has an aspheric surface. In addition, the object of the invention is attained by a projection objective having a lens arrangement having at least a first waist of a pencil of rays, wherein the lens arrangement comprises at least one of the following: a lens having an aspheric surface arranged before the first waist, a lens having an aspheric surface arranged after the first waist, and lenses having aspheric surfaces arranged before and after the first waist.
In a projection objective with a lens arrangement, by the measure of providing, in the forward half of this lens arrangement, at least one lens provided with an aspheric lens surface, the possibility was realized of furnishing a projection objective of compact construction and having a high image quality.
In the division of this lens arrangement into six lens groups: a first lens group having a positive power, a second lens group a negative power, a third lens group a positive power, a fourth lens group a negative power, and a fifth and sixth lens group respectively a positive power, a preferred position of the aspheric surface is at the end of the second lens group. It is then arranged, in particular, on the last lens of the second lens group or at the beginning of the third lens group, and indeed preferably on the first lens of the third lens group. A correction of image errors in the region between the image field zone and the image field edge is possible by means of this aspheric lens surface. In particular, the image errors of higher order, which become evident on considering sagittal sections, can be corrected. Since these image errors apparent in sagittal section are particularly difficult to correct, this is a particularly valuable contribution. In an advantageous embodiment, only one lens has an aspheric surface. This has a positive effect on the production costs, since it is the production of highly accurate aspheric surfaces that requires considerable technological effort, which entails increased costs. It was only with the use of exactly one aspheric lens that it was possible to provide a very compact objective, in which case the additional costs for the aspheric lens are not important, since considerable cost savings were connected with the reduction of the required material and of the surfaces to be processed and tested.
By the measure of providing a lens arrangement that has at least a first waist, an aspheric surface before and an aspheric surface after the waist, a lens arrangement is produced which makes possible a high numerical aperture with high image quality, particularly for the DUV region. In particular, it is possible by the use of these aspheric surfaces to furnish a projection objective of short structure and high image quality. Objectives used in microlithography generally have a high material density over their whole length, so that the reduction of the length is connected with a considerable saving of material. Since only very high-grade materials can be used for projection objectives, particularly for microlithography, the required use of material has a severe effect on the production costs.
The aspheric surface arranged before the first waist can be arranged at the end of the first lens group or at the beginning of the second lens group. Furthermore, it has been found to be advantageous to arrange an aspheric surface, arranged after the first waist, on the last lens of the second lens group or on the first lens of the third lens group.
The aspheric surface provided before the first waist in particular makes possible a targeted correction of coma in the region of the image field zone. This aspheric lens surface has only a slight effect on the skew spherical aberration in tangential section and in sagittal section. In contrast to this, the skew sagittal aberration, particularly in the region between the image field zone and image field edge, can be corrected by the aspheric lens surface after the waist.
The provision of a second aspheric lens surface is thus a worthwhile measure, in order to counter at high numerical aperture a reduction of image quality due to coma.
In a few cases of application, particularly with very high numerical aperture, it has been found to be favorable to provide a projection objective wherein the third lens group has a lens having an aspheric surface, and, in particular, the last lens of the third lens group has an aspheric surface.
It has been found to be advantageous to provide a first lens in the sixth lens group with an aspheric surface for a further correction of coma, especially in the region of the image field edge. For this aspheric lens surface, the first lens of the sixth lens group has been found to be a particularly well suited position.
Furthermore, the numerical aperture can be increased, at constant image quality, by the provision of a further aspheric surface on the last lens of the third lens group.
It is an advantage of the invention to provide a refractive microlithographic projection objective, wherein all aspheric lens surfaces have a vertex radius (R) of at least 300-mm. Thus the aspheric surfaces are provided on long radii, since the production and testing is easier for lens surfaces with long radii. These surfaces are easily accessible to processing equipment because of their low curvature. In particular, surfaces with long radii are accessible with Cartesian coordinates for tactile measurement processes.
It has been found to be advantageous to use at least two different materials for achromatization, for projection objectives designed for an illumination wavelength of less than 200 nm, because of the stronger dispersion of the lenses, even with the use of narrowband light sources. In particular, fluorides, especially CaF2, are known as suitable materials, besides quartz glass.
It has been found to be advantageous to provide at least two lenses of CaF2, which are arranged before an aperture stop in the fifth lens group, for the correction of color transverse errors.
It has been found to be advantageous for the further correction of color errors to integrate an achromat after the aperture stop by means of a positive CaF2 lens and a following negative quartz lens. This arrangement has a favorable effect on the correction of the spherical portions. In particular, longitudinal color errors can be corrected by the lenses after the aperture stop.
A reduction of the longitudinal error already results in general from the shortening of the length of the projection objective. Thus a good achromatization with a reduced use of CaF2 lenses can be attained with the objective according to the invention.



BRIEF DESCRIPTION OF THE DRAWINGS
The invention is described in more detail hereinafter with the aid of preferred embodiments, in which:
FIG. 1 shows a schematic illustration of a projection exposure device;
FIG. 2 shows a lens section through a first lens arrangement of a projection objective with an aspheric lens surface;
FIG. 3 shows a lens section through a second lens arrangement, which has two aspheric lens surfaces;
FIG. 4 shows a lens section through a third lens arrangement, which has three aspheric lens surfaces;
FIGS. 5a–5g illustrate tangential transverse aberrations;
FIGS. 6a–6g illustrate sagittal transverse aberrations;
FIGS. 7a–7f illustrate groove errors of the third lens arrangement with the aid of sections;
FIG. 8 shows a lens section through a fourth lens arrangement, which has three aspheric surfaces;
FIG. 9 shows a lens section through a fifth lens arrangement, which has four aspheric surfaces;
FIG. 10 shows a lens section through a sixth lens arrangement, which has four aspheric surfaces.



DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The principle of the construction of a projection exposure device is first described with the aid of FIG. 1. The projection exposure device 1 has an illuminating device 3 and a projection objective 5. The projection objective includes a lens arrangement 19 with an aperture stop AP, an optical axis 7 being defined by the lens arrangement 19. A mask 9 is arranged between the illuminating device 3 and the projection objective 5, and is supported in the beam path by means of a mask holder 11. Such masks 9 used in microlithography have a micrometer to nanometer structure, which is reduced by means of the projection objective 5 by a factor of up to 10, particularly a factor of four, and is imaged on an image plane 13. A substrate positioned by a substrate holder 17 or a wafer 15 is supported in the image plane 13. The minimum structures which are still resolvable depend on the wavelength λ of the light used for illumination, and also on the numerical aperture of the projection objective 5, the maximum attainable resolution of the projection exposure device 1 increasing with decreasing wavelength of the illuminating device 3 and with increasing numerical aperture of the projection objective 5.
The projection objective 5 contains, according to the invention, at least one aspheric surface to provide a high resolution.
Various embodiments of lens arrangements 19 are shown in FIGS. 2–4 and 8–10.
These projection objectives 5 designed for more stringent requirements for image quality and for resolution, and in particular their lens arrangement 19, are described in more detail hereinafter. The data of the individual lenses L101–130, L201–230, L301–330, L401–429, L501–529, L601–629, can be found in detail in the associated tables. All the lens arrangements 19 have at least one aspheric lens surface 27.
These aspheric surfaces are described by the equation:




  
    P
    ⁡
    
      (
      h
      )
    
  
  =
  
    
      
        
          δ
          ·
          h
          ·
          h
        
        
          1
          +
          
            
              1
              -
              
                
                  (
                  
                    1
                    -
                    EX
                  
                  )
                
                ·
                δ
                ·
                δ
                ·
                h
                ·
                h
              
            
          
        
      
      +
      
        
          C
          1
        
        ⁢
        
          h
          4
        
      
      +
      ...
      +
      
        
          C
          n
        
        ⁢
        
          h
          
            
              2
              ⁢
              n
            
            +
            2
          
        
        ⁢
        
          
        
        ⁢
        δ
      
    
    =
    
      1
      /
      R
    
  




in which P is the arrow height as a function of the radius h (height to the optical axis 7) with the aspheric constants C1 through Cn given in the Tables. R is the vertex angle given in the Tables.

The lens arrangement 19 shown in FIG. 2 has 29 lenses L101–L129 and a plane parallel plate L-130. This lens arrangement 19 can be divided into six lens groups, which are denoted by LG1 for the first lens group through LG6 for the sixth lens group. The first, fifth and sixth lens groups have positive refractive power, while the second lens group LG2 and the fourth lens group LG4, by which a first waist 23 and a second waist 25 are formed, have negative refractive power. This lens arrangement 19 is designed for the wavelength λ=193.3 nm which is produced by a KrF excimer laser, and has an aspheric lens surface 27. A structure width of 0.10 μm is resolvable with this lens arrangement 19 at a numerical aperture of 0.75. On the object side, the light transmitted by the lens arrangement propagates in the form of a spherical wavefront. In the objective, the greatest deviation from the ideal wavefront, also denoted by the RMS factor, is 10.4 mλ with respect to the wavelength λ=193.3 nm. The image field diagonal is 28 mm. The constructional length from mask plane to object plane is only 1,000 mm, and the maximum diameter of a lens is 235 mm.
In this embodiment, this aspheric lens surface 27 is arranged on the side of the lens L110 remote from the illumination device.
The projection objective having the previously mentioned good performance data could for the first time be furnished with the use of this aspheric lens surface. This aspheric lens surface serves to correct image errors and also to reduce the required constructional length, with image quality remaining constant. In particular, image errors of higher order in the region between the image zone and image field edge are corrected here by this aspheric surface. This correction brings about, in particular, an increase in the image quality in the sagittal direction.
The dispersion of the available lens materials increases with shorter wavelengths. Consequently, increased chromatic image errors arise in projection objectives for short wavelengths such as 193 nm or 157 nm. The usual embodiment for 193 nm therefore has quartz glass as the flint and CaF2 as the crown, as lens materials for achromatization.
With an overall minimum use of the problematic CaF2, care has to be taken in that a CaF2 lens L114 in the third lens group LG3 places an increased requirement on the homogeneity of the material, since it is arranged far from the aperture stop AP. For this purpose, however, it has a moderate diameter, which substantially improves the availability of CaF2 with an increased requirement.
For the correction of color transverse error, three CaF2 lenses L119, L120, L121 are arranged in the fifth lens group LG5, before the aperture stop AP. An achromat 37, consisting of a convex CaF2 lens L122 and a following meniscus lens L123 of quartz glass are arranged directly behind the aperture stop AP. These CaF2 lenses can be of lower quality than the CaF2 lens L114, since quality deviations in the middle region can easily be simultaneously corrected for all image field regions (by lens rotation during adjustment).
A further CaF2 lens L129 is arranged in the sixth lens group. It is possible by means of this lens of CaF2 to reduce the effects of lens heating and refractive index changes due to irradiation, named compaction.
The individual data for the lenses L101–L130 can be found in Table 1. The optically utilized diameter of all the CaF2 lenses is less than 235 mm. Since the availability of CaF2 is furthermore limited in dependence on the diameter required, the required diameter of the CaF2 lenses used is of central importance.
A lens arrangement 19 designed for the wavelength λ=248 nm is shown in section in FIG. 3. This lens arrangement 19 has two aspheric lens surfaces 27, 29. The first aspheric lens surface 27 is arranged on the image side on the lens L210. It can also be provided to arrange this second aspheric lens surface 27 on the side of the lens L211 facing toward the illumination device. The two lenses L210 and L211 are predetermined for the reception of the aspheric lens surface 27. Provision can also be made to provide a meniscus lens having an aspheric lens surface instead of the lenses L210 and L211. The second aspheric lens surface 29 is arranged in the end region of the first lens group, on the side of the lens L205 remote from the illumination device 3. It can also be provided to arrange this aspheric lens surface 29 on the lens L206 following thereafter in the beginning of the second lens group.
A particularly great effect is obtained when the aspherics 27, 29 are arranged on lens surfaces at which the incident rays include a large angle with the respective surface normals. In this case the large variation of the angle of incidence is important. In FIG. 10, the value of sin i at the aspheric lens surface 31 reaches a value of up to 0.82. Because of this, the two mutually facing lens surfaces of lenses L210, L211 in this embodiment have a greater effect on the course of the rays in comparison with the respective other lens surfaces of the corresponding lenses L210, L211.
With a length of 1,000 mm and a maximum lens diameter of 237.3 mm, this lens arrangement has a numerical aperture of 0.75 at a wavelength of 193.3 nm. The image field diagonal is 27.21 mm. A structure width of 0.15 μm is resolvable. The greatest deviation from the ideal wavefront is 13.0 mλ. The exact lens data with which these performance data were attained can be found in Table 2.
A further embodiment of a lens arrangement 19 for the wavelength 248.38 nm is shown in FIG. 4. This lens arrangement 19 has three lenses L305, L310, L328 which respectively have an aspheric lens surface 27, 29, 31. The aspheric lens surfaces 27, 29 have been left at the positions given by FIG. 3. The coma of middle order can be adjusted for the image field zone by means of the aspheric lens surface 27. The repercussions on sections in the tangential direction and in the sagittal direction are then small.
The additional, third aspheric lens surface 31 is arranged on the mask side on the lens L328. The aspheric lens surface 31 supports coma correction toward the image field edge.
By means of these three aspheric lens surfaces 27, 29, 31, there are attained, at a wavelength of 248.38 nm and at a length of only 1,000 mm and a maximum lens diameter of 247.2 mm, the further increased numerical aperture of 0.77 and a structure width of 0.14 μm which can be well resolved in the whole image field. The maximum deviation from the ideal wavefront is 12.0 mλ.
In order to keep the diameter of the lenses in LG5 small, and in order for a Petzval sum which, advantageously for the system, should be kept nearly zero, the three lenses L312, L313, L314 in the third lens group LG3 are enlarged. The thicknesses, and thus the diameters, of other lenses, particularly the lenses of the first group LG1, have been reduced in order to furnish the required axial constructional space for these three lenses L312–L314. This is an excellent way to arrange very large image fields and apertures in a restricted constructional space.
The high image quality which is attained by this lens arrangement can be seen in FIGS. 5a–5g, 6a–6g and 7a–7f. 
FIGS. 5a–5g give the meridional transverse aberration DYM for the image height Y′ (in mm). All show an outstanding course up to the highest DW′.
FIGS. 6a–6g give the sagittal transverse aberrations DZS as a function of the half aperture angle DW′ for the same image heights mm).
FIGS. 7a–7f give the groove error DYS, which is nearly zero throughout.
The exact lens data can be found in Table 3; the aspheric lens surfaces 27, 29, 31 have a considerable participation in the high image quality which can be ensured.
A further lens arrangement for the wavelength λ=248.38 nm is shown in FIG. 8. With a length of only 1,000 mm, this lens arrangement 19 has, with only three aspheric lens surfaces 27, 29, 31, a numerical aperture of 0.8; a structure width of 0.13 μm is well resolvable in the whole image field, whose diagonal is 27.21 mm. The maximum lens diameter is 255 mm and occurs in the region of the fifth lens group LG5. The lens diameter is unusually small for the numerical aperture of 0.8 at an image field having a 27.21 mm diagonal. All three aspheric lens surfaces 27, 29, 31 are in the front lens groups LG1–LG3 of the lens arrangement 19. The deviation from the ideal wavefront is only 9.2 mλ in this lens arrangement.
The exact lens data of this lens arrangement can be found in Table 4.
A further increase of the numerical aperture, from 0.8 to 0.85, could be attained by the provision of a further, fourth aspheric 33 on the side of the lens L513 remote from the illuminating device. This high numerical aperture, from which there results an acceptance angle of 116.4°, as against an angle of 88.8° with a numerical aperture of 0.70, is unparalleled for the image field with diagonal 27.21 mm. The well resolvable structure width is 0.12 μm, and the maximum deviation from the ideal wavefront is only 7.0 mλ. Such a lens arrangement 19 is shown in FIG. 9, and the exact lens data can be found in Table 5.
In comparison with the preceding embodiments of FIGS. 1–3 and with the cited DE 198 18 444 A, the last two lenses are united into one lens in this lens arrangement 19. By this measure, in addition to the savings in lens production, a lens mounting can be saved in the end region, so that constructional space is created for auxiliary devices, especially for a focus sensor.
A lens arrangement 19 designed for the wavelength λ=157.63 nm is shown in FIG. 10 and the exact data can be found in Table 6. The image field which can be illuminated with this lens arrangement has been reduced to 6×13 mm, with an image field diagonal of 14.3 mm, and is adapted for the stitching process.
With a length of only 579.5 mm and a maximum diameter of 167 mm, and with four aspheric lens surfaces 27, 29, 31, 33, a numerical aperture of 0.85 and a well resolvable structure width of 0.07 μm were attained. The deviation from the ideal wavefront is 9.5 mλ at the wavelength λ=157.63 nm.
The absorption of quartz lenses is quite high because of the short wavelength, so that recourse was increasingly had to CaF2 as the lens material. Single quartz glass lenses are provided in the region of the waists 23, 25, i.e., in the second and fourth lens groups LG2 and LG4. These quartz glass lenses are to have the highest possible transmission. A further lens of quartz glass, in the form of a meniscus lens L625, is provided in the lens group LG5 to form an achromat. Furthermore in lens group LG6, the lens L628 having an aspheric lens surface is of quartz glass. The aspheric surface 33 is thus constituted of the material which is easier to process.
The color longitudinal error of this lens arrangement 19 is thus very small, even at this very high numerical aperture.
The embodiments hereinabove show that good performance data can be attained without aspheric surfaces (27, 29, 31, 33) having large diameters, especially in the fifth lens group. The small aspheric lens surfaces utilized can easily be made and tested.
These lens arrangements 19 illustrated in the embodiments show solely the design space set out by the claims. Of course, the features according to the claims and their combinations, put in concrete terms with the aid of the embodiments, can be combined with each other.











TABLE 1





m709a






Lenses
Radii
Thicknesses
Glasses
1⁄2 × Lens Diameter




















infinity
17.2885

62.436


L101
−143.20731
6.0000
SIO2
62.972



599.77254
7.6370
He
70.359


L102
−3259.25331
17.8056
SIO2
72.015



−215.68976
.7500
He
74.027


L103
6352.48088
21.0301
SIO2
79.278



−222.97760
.7500
He
80.492


L104
375.05253
22.1160
SIO2
83.813



−496.09705
.7500
He
83.813


L105
191.46102
26.2629
SIO2
81.276



−1207.32624
.7500
He
80.032


L106
180.94629
15.5881
SIO2
72.339



100.48825
25.3787
He
62.801


L107
−3031.88082
6.0000
SIO2
62.147



122.14071
23.8679
He
58.984


L108
−295.91467
9.3246
SIO2
59.196



−187.69852
.7500
He
59.874


L109
−199.96963
6.0000
SIO2
59.882



184.23629
33.9482
He
62.911


L110
−112.01095
6.0000
SIO2
64.128



−684.63799 A
12.5079
He
75.868


L111
−225.51622
18.6069
SIO2
78.258



−137.30628
.7500
He
81.928


L112
5312.93388
38.3345
SIO2
99.979



−178.79712
.7500
He
101.920


L113
344.71979
39.8511
SIO2
111.294



−397.29552
.7500
He
111.237


L114
165.51327
39.6778
CAF2
101.552



7755.09540
.7500
He
99.535


L115
195.28524
23.8921
SIO2
87.267



119.99272
32.2730
He
72.012


L116
−452.93918
6.0000
SIO2
70.763



287.33119
20.7820
He
66.677


L117
−218.82578
6.0000
SIO2
66.150



166.44429
40.5757
He
66.003


L118
−103.90786
6.4932
SIO2
66.694



5916.68891
13.3336
He
80.535


L119
−344.93456
19.8584
CAF2
82.790



−165.11801
.7500
He
86.174


L120
−11871.72431
38.5095
CAF2
100.670



−174.34079
.7500
He
102.666


L121
586.98079
31.6915
CAF2
111.739



−414.20537
.7500
He
112.097



infinity
3.6849
He
111.399



Stop
.0000
He
111.399



infinity
1.2566
He
111.830


L122
284.64742
45.7670
CAF2
114.801



−414.78783
17.9539
He
114.410


L123
−234.72451
14.5097
SIO2
113.062



−593.08647
14.7730
He
114.454


L124
−323.13567
42.1874
SIO2
114.235



−229.06128
.7500
He
117.505


L125
180.27184
31.4105
SIO2
105.659



652.02194
.7500
He
103.698


L126
143.20049
28.2444
SIO2
91.476



383.51531
14.7177
He
88.206


L127
−2122.47818
14.1140
SIO2
85.843



312.60012
1.3119
He
74.816


L128
111.92162
46.5147
SIO2
66.708



53.69539
2.2604
He
40.084


L129
51.14657
27.3776
CAF2
39.074



492.53747
3.7815
He
32.621



infinity
3.0000
SIO2
29.508



infinity
12.0000

27.848



infinity


14.021










Aspheric Constants:


Coefficients of the aspheric surface n:


[where n is 21]












EX = 0.0000



C1 = 0.61839643 * 10−8



C2 = −0.11347761 * 10−11



C3 = 0.32783915 * 10−15



C4 = −022000186 * 10−20





















TABLE 2





m736a






Lenses
Radii
Thicknesses
Glasses
1⁄2 × Lens Diameter




















infinity
16.6148

60.752


L201
−140.92104
7.0000
SIO2
61.267



−4944.48962
4.5190

67.230


L202
−985.90856
16.4036
SIO2
68.409



−191.79393
.7500

70.127


L203
18376.81346
16.5880
SIO2
73.993



−262.28779
.7500

74.959


L204
417.82018
21.1310
SIO2
77.129



−356.76055
.7500

77.193


L205
185.38468
23.3034
SIO2
74.782



−1198.61550 A
7500

73.634


L206
192.13950
11.8744
SIO2
68.213



101.15610
27.6353

61.022


L207
−404.17514
7.0000
SIO2
60.533



129.70591
24.1893

58.732


L208
−235.98146
7.0584
SIO2
59.144



−203.88450
.7500

60.201


L209
−241.72595
7.0000
SIO2
60.490



196.25453
33.3115

65.017


L210
−122.14995
7.0000
SIO2
66.412



−454.65265 A
10.8840

77.783


L211
−263.01247
22.6024
SIO2
81.685



−149.71102
1.6818

86.708


L212
−23862.31899
43.2680
SIO2
104.023



−166.87798
.7500

106.012


L213
340.37670
44.9408
SIO2
115.503



−355.50943
.7500

115.398


L214
160.11879
41.8646
SIO2
102.982



4450.50491
.7500

100.763


L215
172.51429
14.8261
SIO2
85.869



116.88490
35.9100

74.187


L216
−395.46894
7.0000
SIO2
72.771



178.01469
28.0010

66.083


L217
−176.03301
7.0000
SIO2
65.613



188.41213
36.7224

66.293


L218
−112.43820
7.0059
SIO2
66.917



683.42330
17.1440

80.240


L219
−350.01763
19.1569
SIO2
82.329



−194.58551
.7514

87.159


L220
−8249.50149
35.3656
SIO2
99.995



−213.88820
.7500

103.494


L221
657.56358
31.3375
SIO2
114.555



−428.74102
.0000

115.245



infinity
2.8420

116.016



Stop
.0000

116.016


L222
820.30582
27.7457
SIO2
118.196



−520.84842
18.4284

118.605


L223
330.19065
37.7586
SIO2
118.273



−672.92481
23.8692

117.550


L224
−233.67936
10.0000
SIO2
116.625



−538.42627
10.4141

117.109


L225
−340.26626
21.8583
SIO2
116.879



−224.85666
.7500

117.492


L226
146.87143
34.5675
SIO2
100.303



436.70958
.7500

97.643


L227
135.52861
29.8244
SIO2
86.066



284.57463
18.9234

79.427


L228
−7197.04545
11.8089
SIO2
72.964



268.01973
.7500

63.351


L229
100.56453
27.8623
SIO2
56.628



43.02551
2.0994

36.612


L230
42.30652
30.9541
SIO2
36.023



262.65551
1.9528

28.009



infinity
12.0000

27.482



infinity


13.602










Aspheric Constants:





Coefficients of the aspheric surface n:


[where n is 29]









EX = −0.17337407 * 103



C1 = 0.15292522 * 10−7



C2 = 0.18756271 * 10−11



C3 = −0.40702661 * 10−16



C4 = 0.26176919 * 10−19



C5 = −0.36300252 * 10−23



C6 = 0.42405765 * 10−27







Coefficients of the aspheric surface n:


[where n is 27]









EX = −0.36949981 * 101



C1 = 0.20355563 * 10−7



C2 = −0.22884234 * 10−11



C3 = −0.23852614 * 10−16



C4 = −0.19091022 * 10−19



C5 = 0.27737562 * 10−23



C6 = −0.29709625 * 10−27





















TABLE 4





m791a






Lenses
Radii
Thicknesses
Glasses
1⁄2 × Lens Diameter




















infinity
11.4557

61.339


L401
−273.19566
7.0000
SIO2
62.263



−277.09708
.7000

63.765


L402
−861.38886
8.9922
SIO2
64.989



−339.26281
.7000

65.826


L403
118124.13719
11.2867
SIO2
66.916



−365.70154
.7000

67.416


L404
685.10936
13.1651
SIO2
67.995



−485.98278
.7000

68.012


L405
387.56973
17.2335
SIO2
67.247



−473.09537 A
.7000

66.728


L406
268.03965
9.9216
SIO2
62.508



149.12863
23.8122

58.531


L407
−184.82383
7.0000
SIO2
58.029



176.80719
21.4194

57.646


L408
−186.59114
7.0000
SIO2
58.045



218.73570
29.5024

63.566


L409
−129.31068
7.0000
SIO2
65.030



−531.44773 A
17.2306

76.481


L410
−307.52016
22.4527
SIO2
85.643



−148.36184
.7000

88.946


L411
−1302.18676
41.0516
SIO2
105.065



−162.48723
.7000

107.106


L412
621.16978
41.1387
SIO2
118.007



−294.49119
.7000

118.347


L413
160.06951
49.7378
SIO2
109.803



−2770.71439 A
7000

107.961


L414
152.16529
16.7403
SIO2
89.160



106.43165
39.9369

76.189


L415
−530.55958
7.0000
SIO2
74.955



170.63853
31.4993

68.381


L416
−164.61084
7.0000
SIO2
67.993



262.65931
36.2904

69.679


L417
−113.57141
8.4328
SIO2
70.272



772.56149
21.7682

85.377


L418
−278.33295
16.4890
SIO2
87.710



−198.24799
.8689

92.554


L419
−3464.64038
37.5900
SIO2
107.590



−214.63481
1.1929

111.045


L420
2970.07848
32.3261
SIO2
122.434



−350.93217
2.5303

123.849


L421
1499.34256
25.8265
SIO2
127.128



−561.19644
.0000

127.371



infinity
.7510

126.559



stop
.0000

126.559


L422
821.09016
39.5191
SIO2
127.453



−1995.20557
.7000

127.499


L423
337.02437
41.8147
SIO2
126.619



−659.23025
25.0233

125.851


L424
−242.66564
7.0000
SIO2
124.960



−891.19390
9.7905

125.057


L425
−492.17516
41.0678
SIO2
124.887



−242.55195
.7000

125.845


L426
145.04614
37.2406
SIO2
104.033



406.88892
.7008

101.079


L427
119.31280
31.5532
SIO2
85.742



249.69473
15.2917

79.561


L428
1411.93157
7.8700
SIO2
74.994



281.90273
.7011

66.830


L429
143.95136
55.0835
SIO2
61.517



404.13980
15.0000

32.177



infinity
.0001

13.603



infinity


13.603










Aspheric Constants:





Coefficients of the aspheric surface n:


[where n is 27]









EX = 0.45321787 * 102



C1 = 0.12027601 * 10−7



C2 = −0.16206398 * 10−11



C3 = −0.41686011 * 10−15



C4 = 0.38440137 * 10−19



C5 = −0.15095918 * 10−23



C6 = −0.84812561 * 10−28







Coefficients of the aspheric surface n:


[where n is 29]









Ex = 0



C1 = −0.97452539 * 10−7



C2 = 0.32591079 * 10−11



C3 = 0.97426255 * 10−16



C4 = −0.846124 * 10−20



C5 = −0.12332031 * 10−23



C6 = 0.14443713 * 10−27







Coefficients of the aspheric surface n:


[where n is 33]









Ex = 0



C1 = 0.53144137 * 10−8



C2 = 0.21837618 * 10−12



C3 = 0.22801998 * 10−18



C4 = −0.87807963 * 10−21



C5 = 0.42592446 * 10−25



C6 = −0.85709164 * 10−30





















TABLE 5





j430a






Lenses
Radii
Thicknesses
Glasses
1⁄2 × Lens Diameter




















infinity
9.9853

61.649


L501
−265.92659
6.0000
SIO2
62.237



857.92226
5.9813

65.916


L502
−2654.69270
14.4343
SIO2
66.990



−244.65690
.7500

68.482


L503
1038.40194
15.9955
SIO2
71.883



−333.95446
.7500

72.680


L504
359.47552
18.5128
SIO2
74.430



−532.67816
.7500

74.416


L505
213.38035
21.4562
SIO2
72.985



−1441.22634 A
7500

72.045


L506
261.90156
6.5306
SIO2
67.809



115.92184
28.4856

62.818


L507
−267.21040
6.0000
SIO2
62.411



175.09702
23.2443

61.923


L508
−213.08557
6.0000
SIO2
62.365



199.61141
30.8791

68.251


L509
−158.73046
6.0337
SIO2
69.962



−1108.92217 A
10.9048

81.119


L510
−314.37706
20.6413
SIO2
84.163



−169.59197
.8014

88.902


L511
−3239.97175
43.6396
SIO2
106.289



−168.44726
.7500

108.724


L512
495.41910
48.8975
SIO2
123.274



−288.85737
.7500

123.687


L513
153.24868
48.7613
SIO2
113.393



920.32139 A
.7500

111.134


L514
163.02602
15.7110
SIO2
96.188



124.97610
44.2664

84.961


L515
−422.99493
6.0000
SIO2
83.633



184.60620
31.4986

76.498


L516
−241.93022
6.0000
SIO2
76.180



168.30899
51.3978

77.396


L517
−117.43130
6.5332
SIO2
78.345



2476.47953
21.4666

98.469


L518
−311.36041
15.2223
SIO2
101.209



−221.58556
.7500

105.324


L519
−934.37047
37.6761
SIO2
122.239



−216.75809
.7500

125.425


L520
3623.94786
39.6266
SIO2
146.583



−370.69232
1.1289

148.219


L521
1209.82944
39.1543
SIO2
157.194



−613.71745
.0000

157.954



infinity
.7500

158.061



stop
.0000

158.061


L522
709.88915
36.2662
SIO2
160.170



−1035.75796
.7500

160.137


L523
313.44889
58.8000
SIO2
155.263



−1046.56219
28.7484

153.730


L524
−328.67790
15.0000
SIO2
152.447



−1283.32936
14.7084

148.826


L525
−540.24577
23.9839
SIO2
148.336



−305.19883
.7510

148.189


L526
152.28321
42.3546
SIO2
114.055



384.50964
.7531

109.924


L527
124.66784
31.8554
SIO2
91.106



279.60513
16.6796

86.038


L528
−28987.53974
7.4387
SIO2
82.126



316.02224
.8631

72.044


L529
180.51161
54.1269
SIO2
67.036



1341.25511
15.0000

37.374



infinity-
.0001

13.604



infinity-


13.604










Aspheric Constants:





Coefficients of the aspheric surface n:


[where n is 29]









EX = −0.27012883 * 103



C1 = −0.48014089 * 10−7



C2 = 0.30075830 * 10−11



C3 = 0.34922943 * 10−16



C4 = 0.26946301 * 10−19



C5 = −0.58250631 * 10−23



C6 = 0.68991391 * 10−27







Coefficients of the aspheric surface n:


[where n is 27]









EX = 0.41249481 * 101



C1 = −0.38239182 * 10−8



C2 = −0.14976009 * 10−11



C3 = −0.25206193 * 10−18



C4 = −0.78282128 * 10−20



C5 = 0.13017800 * 10−23



C6 = −0.14205614 * 10−27







Coefficients of the aspheric surface n:


[where n is 33]









EX = 0.26320110 * 101



C1 = 0.27448935 * 10−8



C2 = −0.18100074 * 10−12



C3 = 0.58696756 * 10−17



C4 = −0.58955753 * 10−21



C5 = 0.16526308 * 10−25



C6 = −0.25708759 * 10−30







Coefficients of the aspheric surface n:


[where n is 31]









EX = −0.96865859 * 105



C1 = −0.42411179 * 10−8



C2 = 0.12306068 * 10−12



C3 = 0.69229786 * 10−17



C4 = 0.80135737 * 10−20



C5 = −0.14022540 * 10−23



C6 = 0.79827308 * 10−28





















TABLE 6





m767a






Lenses
Radii
Thicknesses
Glasses
1⁄2 × Lens Diameter




















infinity
5.9005
N2
32.429


L601
−125.95821
3.6410
CAF2
32.780



243.24465
5.2309
He
35.323


L602
2472.77263
9.2265
CAF2
36.826



−132.46523
.3958
He
37.854


L603
544.60759
8.6087
CAF2
40.080



−188.98512
.6007
He
40.516


L604
180.26444
10.3984
CAF2
41.764



−394.70139
.4244
He
41.743


L605
101.06312
12.8236
CAF2
40.955



−691.58627 A
.5111
He
40.455


L606
135.75849
3.1245
CAF2
37.553



57.03094
16.2396
He
34.284


L607
−268.26919
5.9149
CAF2
33.871



116.53669
10.9654
He
33.188


L608
−142.54676
3.2195
SIO2
33.372



100.09171
16.1921
He
35.360


L609
−83.03185
3.2311
SIO2
36.264



−453.73264 A
5.1711
He
41.718


L610
−167.92924
12.0560
CAF2
43.453



−93.29791
.4204
He
47.010


L611
−1270.46545
24.2891
CAF2
56.224



−90.89540
1.1471
He
58.224


L612
266.81271
25.6379
CAF2
66.498



−171.23687
.3519
He
66.755


L613
82.41217
26.8409
CAF2
61.351



529.17259 A
.5132
He
60.098


L614
81.87977
8.2278
CAF2
50.462



64.06536
22.9801
He
44.346


L615
−259.83061
3.3437
SIO2
43.473



124.29419
13.5357
He
40.266


L616
−197.29109
3.0000
SIO2
39.809



87.83707
24.5613
He
39.571


L617
−64.97274
4.6170
SIO2
40.050



1947.71288
9.3909
He
49.830


L618
−182.16003
7.8052
CAF2
51.480



−118.82950
.3753
He
53.449


L619
−633.93522
19.7976
CAF2
63.119



−115.14087
.3706
He
64.793


L620
2647.04517
19.8039
CAF2
75.458



−197.41705
2.7167
He
76.413


L621
668.45083
30.1057
CAF2
81.369



−322.45899
.0001
He
82.659



infinity
.3948
He
82.583



stop
.0000

82.583


L622
395.84774
16.8734
CAF2
83.488



−635.79877
.3500
He
83.449


L623
165.28880
28.1341
CAF2
80.761



−698.21798
15.6657
He
80.133


L624
−175.54365
7.9803
SIO2
79.485



−571.27581
9.7972
He
78.592


L625
−265.73712
11.6714
CAF2
78.015



−156.05301
.3500
He
78.036


L626
79.45912
22.6348
CAF2
60.151



199.26460
.3500
He
57.925


L627
67.01872
15.8836
CAF2
48.063



140.01631
8.6050
He
45.305


L628
2265.71693 A
4.0939
SIO2
43.177



167.06050
2.0915
He
38.352


L629
102.24013
24.5664
CAF2
34.878



662.00756
9.4740
N2
22.044



UNENDL
.0001
N2
7.166



UNENDL


7.166










Aspheric Constants:





Coefficients of the aspheric surface n:


[where n is 29]









EX = −0.7980946 * 102



C1 = −0.21353640 * 10−6



C2 = 0.56257 * 1010



C3 = −0.39122939 * 10−14



C4 = −0.24089766 * 10−18



C5 = 0.30268982 * 10−22



C6 = 0.1437923 * 10−25







Coefficients of the aspheric surface n:


[where n is 27]









EX = 0.1660595 * 101



C1 = −0.12449719 * 10−7



C2 = −0.39565 * 10−10



C3 = −0.10241741 * 10−14



C4 = −0.19631485 * 10−17



C5 = 0.11604236 * 10−20



C6 = −0.4669584 * 10−24







Coefficients of the aspheric surface n:


[where n is 33]









EX = 0.1614147 * 100



C1 = 0.14130608 * 10−7



C2 = −0.9747553 * 10−11



C3 = 0.20478684 * 10−15



C4 = −0.17732262 * 10−18



C5 = 0.29715991 * 10−22



C6 = −0.19032581 * 10−26







Coefficients of the aspheric surface n:


[where n is 31]









EX = 0



C1 = −0.18139679 * 10−7



C2 = 0.26109069 * 10−11



C3 = 0.23340548 * 10−14



C4 = 0.29943791 * 10−17



C5 = −0.13596787 * 10−20



C6 = 0.21788235 * 10−24

## Claims

1. A refractive microlithographic projection objective, having a lens arrangement comprising at least one lens with an aspheric lens surface, wherein all aspheric lens surfaces have a vertex radius (R) of at least 350 mm.

2. The projection objective for microlithography according to claim 1, wherein the diameter of said lens having an aspheric surface is smaller than 90% of the maximum diameter of said lens arrangement.

3. A projection objective comprising:
a lens arrangement comprising at least two lenses having an aspheric surface, the lens arrangement having at least one waist between two lenses having an aspheric surface,
wherein said lens arrangement comprises lenses of at least two materials from a group consisting of quartz glass and fluorides.

4. The projection objective according to claim 3, wherein said lens arrangement does not exceed a maximum lens diameter of between 250 mm and 280 mm.

5. The projection objective according to claim 3, having an object side and an image side, wherein said lens arrangement has on said image side a numerical aperture of between 0.80 and 0.85.

6. The projection objective according to claim 3, further comprising an aperture stop wherein at least a last two positive lenses before said aperture stop are comprised of CaF2.

7. A refractive microlithographic projection objective according to claim 3, having a lens arrangement comprising at least one lens with an aspheric lens surface, wherein all aspheric lens surfaces have a vertex radius (R) of at least 350.

8. The projection objective for microlighography according to claim 3, wherein the diameter of said lens having an aspheric surface is smaller than 90% of the maximum diameter of said lens arrangement.

9. A projection objective comprising:
a lens arrangement having at least one waist,
an aperture stop arrangement in said lens arrangement, at least one lens having an aspheric surface being arranged after said aperture stop arrangement in a direction of propagation of radiation, and
at least one lens comprising fluoride.

10. The projection objective according to claim 9, wherein said lens arrangement does not exceed a maximum lens diameter of between 250 mm and 280 mm.

11. The projection objective according to claim 9, having an objective side and an image side, wherein said lens arrangement has on said image side a numerical aperture of between 0.80 and 0.85.

12. The projection objective according to claim 9, having an objective side and an image side, wherein said lens arrangement has on said image side a numerical aperture of between 0.80 and 0.85.

13. The projection objective according to claim 9, further comprising an aperture stop wherein at least a last two positive lenses before said aperture stop are comprised of CaF2.

14. A refractive microlithographic projection objective according to claim 9, having a lens arrangement comprising at least one lens with an aspheric lens surface, wherein all aspheric lens surfaces have a vertex radius (R) of at least 350 mm.

15. The projection objective for microlithography according to claim 9, wherein the diameter of said lens having an aspheric surface is smaller than 90% of the maximum diameter of said lens arrangement.

16. A projection exposure device for microlithography, comprising an excimer laser light source emitting radiation of wavelength shorter than 250 nm, and a projection objective according to claim 9.

17. A projection objective according to claim 9, comprising:
a first lens group having positive power;
a second lens group having negative power;
a third lens group having positive power; and
a fourth lens group having negative power;
wherein a lens at the end of said second lens group has an aspheric surface.

18. A projection objective according to claim 9, comprising:
a lens arrangement comprising at least two lenses having an aspheric surface, the lens arrangement having at least one waist between two lenses having an aspheric surface,
wherein said lens arrangement comprises lenses of at least two materials from a group consisting of quarts glass and fluorides.

19. The projection objective for microlithography according to claim 1, wherein all aspheric lens surfaces have a vertex radius (R) of at most 1,000 mm.

20. The projection objective for microlithography according to claim 1, wherein all aspheric lens surfaces have a vertex radius (R) of at least 1,000 mm.

21. The projection objective for microlithography according to claim 7, wherein all aspheric lens surfaces have a vertex radius (R) of at most 1,000 mm.

22. The projection objective for microlithography according to claim 7, wherein all aspheric lens surfaces have a vertex radius (R) of at least 1,000 mm.

23. The projection objective for microlithography according to claim 14, wherein all aspheric lens surfaces have a vertex radius (R) a value of at most 1,000 mm.

24. The projection objective for microlithography according to claim 14, wherein all aspheric lens surfaces have a vertex radius (R) of at least 1,000 mm.