JPH11133301A - Projection optical system exposure device and manufacture of semi-conductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a projection optical system whose exposure range is sufficiently wide, whose numerical aperture is sufficiently large and which is constituted so that the outside diameter of a lens is sufficiently suppressed from being enlarged. SOLUTION: The projection optical system projecting the image of a 1st substance R on a 2nd substance W is constituted of a 1st lens group G1 having positive power, a 2nd lens group G2 having negative power, a 3rd lens group G3 having the positive power and a 4th lens group G4 having the positive power in turn from the 1st substance R side. In such a case, when a distance on an optical axis between a focus position formed by the whole projection optical system and the lens surface positioned at the nearest position to the substance R side in the projection optical system when paraxial luminous flux parallel with the optical axis is made incident from the substance W side of the projection optical system is defined as En, a distance between the substance and the image of the projection optical system is defined as TT and the projecting magnification of the projection optical system is defined as β, the conditions of |En|/TT>2.5 and -0.179<β<-0.125 are satisfied.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus for manufacturing a semiconductor device by transferring a circuit pattern on a projection original onto a photosensitive substrate, and more particularly to a projection optical system used for the exposure apparatus.

[0002]

2. Description of the Related Art Conventionally, various optical systems have been proposed as projection optical systems used in exposure apparatuses for manufacturing semiconductor devices. Among them, an optical system in which both sides on the object side (projection master side) and the image side (photosensitive substrate side) are substantially telecentric is disclosed in, for example, JP-A-3-88317 and JP-A-4-157412. And so on.

[0003]

However, there is a need for a high-resolution projection optical system capable of forming a finer circuit pattern on a semiconductor device. System high NA (numerical aperture)
Is required. Therefore, for example, even in an exposure apparatus using a KrF excimer laser as a light source, a projection optical system having a larger numerical aperture is required, and as the numerical aperture increases, the lens outer diameter of the projection optical system tends to increase. It is in. On the other hand, in order to form a finer pattern in a good condition, the requirements for lens production such as uniformity of glass material and processing accuracy of the lens surface shape become strict. , Which further promotes these manufacturing difficulties. In addition, as the lens outer diameter increases, the volume of the glass material increases, leading to an increase in cost.
Accordingly, the present invention provides a projection optical system having a sufficiently wide exposure range, a sufficiently large numerical aperture, and a sufficiently suppressed enlargement of the lens outer diameter, an exposure apparatus using the projection optical system, and an exposure apparatus. An object of the present invention is to provide a method for manufacturing a semiconductor device using a semiconductor device.

[0004]

In order to solve the above-mentioned problems, a projection optical system according to the present invention converts an image of a first object into a second image.
A projection optical system for projecting onto an object, comprising, in order from the first object side, a first lens group having a positive power, a second lens group having a negative power, a third lens group having a positive power, And a fourth lens group having the following power and satisfying the following condition. (1) | En | / TT> 2.5 (2) −0.179 <β <−0.125 where En: A paraxial light beam parallel to the optical axis is incident from the second object side of the projection optical system. In this case, the distance on the optical axis between the focal position formed by the entire projection optical system and the lens surface located closest to the first object in the projection optical system TT: distance between object images of the projection optical system β: projection This is the projection magnification of the optical system. The focal position formed by the entire projection optical system corresponds to the position of the entrance pupil of the projection optical system.

In the projection optical system of the present invention, the first lens group having a positive power (refractive power) is closest to the first object side so that the projection optical system is substantially telecentric toward the first object side. Be placed. The second lens group and the third lens group have a negative power (refractive power) and a positive power (refractive power), respectively, and thus have an inverse telephoto configuration when viewed from the first object side. Therefore, the configuration is such that light rays from the first object plane having a wide field of view are guided to the projection optical system. Further, the fourth lens group having a positive power (refractive power) forms an image of the light beam thus guided as a light beam with a large numerical aperture. Conditional expression (1) defines an image-side telecentric optical system in order to prevent a magnification error from occurring even if the second object plane serving as an image plane is positioned with an error in the optical axis direction. This is a condition for configuring. If the lower limit of conditional expression (1) is exceeded, the telecentricity deteriorates and magnification errors tend to occur, which is not preferred.

The conditional expression (2) defines an appropriate range of the magnification β of the projection optical system. Conventionally proposed reduction projection optical systems have 1/10 times, 1/5 times, 1
Optical systems having a projection magnification of / 4 times, 1 / 2.5 times, etc. have been proposed. Of these, in a semiconductor manufacturing process, a projection exposure apparatus used in a step of printing the finest pattern called a critical layer often uses a 1/5 or 1/4 optical system. . In the history of development in the past, these magnifications have been used in order to satisfy various conditions such as avoiding the influence of transfer of dust while maintaining a certain wide field of view and high resolution. However, in order to increase the numerical aperture for higher resolution, the lens diameter becomes too large in the conventional magnification system,
This leads to manufacturing difficulties. In order to increase the numerical aperture without increasing the lens diameter, it is of course to compensate for spherical aberration, but this can be solved to some extent by securing a sufficient number of lenses. However, in order to compensate for the Pebbal sum, it is unavoidable to arrange a positive lens at a high position of a paraxial ray and a negative lens at a low position. Therefore, when the numerical aperture is increased, the lens diameter is increased accordingly.

Therefore, by increasing the reduction ratio of the projection lens and relatively increasing the power of the negative lens group,
The Pebbal sum can be more easily guided in the negative direction, the positive lens group can be arranged at a position where the paraxial ray is relatively low, and the lens diameter can be reduced. In other words, a preferable projection magnification for realizing an optical system having a large numerical aperture can be defined by the conditional expression (2). If the lower limit of conditional expression (2) is exceeded, the reduction ratio does not increase so much. On the other hand, when the value exceeds the upper limit of the conditional expression (2), the area of the first object plane becomes larger than the exposure area on the image plane, so that not only is it difficult to correct the distortion, but also the original plate serving as the first object Is not preferable because the manufacturing difficulty increases and the influence of bending due to gravity cannot be ignored. The upper limit of conditional expression (2) is −0.0.
More preferably, it is set to 15.

It is an object of the present invention to provide a projection optical system which can suppress an increase in the outer diameter of a lens even if the numerical aperture has a sufficiently large numerical aperture. Therefore, in order to fully enjoy the effects of the present invention, when the image-side maximum numerical aperture of the projection optical system is NA, NA is sufficiently large, that is, for example, NA> 0.5.
It is preferable to form them so that NA ≧ 0.65
The case is even more so. In the present invention, the first lens group includes at least two positive lenses, the second lens group includes at least three negative lenses,
The third lens group includes at least two positive lenses.
Preferably, the lens group includes at least five positive lenses and at least three negative lenses.

In the present invention, (3) 0.1 <F1 / TT <0.4 (4) 0.03 <-F2 / TT <0.07 (5) 0.05 <F3 / TT <0 0.3 (6) It is preferable that the condition 0.04 <F4 / TT <0.2 is satisfied. Where F1: focal length of the first lens group F2: focal length of the second lens group F3: focal length of the third lens group F4: focal length of the fourth lens group.

The conditional expressions (3) to (6) are respectively
This defines an appropriate power range of the fourth lens group. If the upper limit of conditional expression (3) is exceeded, the second and fourth conditions must be satisfied.
It is not preferable because negative distortion generated in the lens group cannot be completely corrected by the first lens group. More preferably, the upper limit of condition (3) should be set at 0.3. Conversely, when the value goes below the lower limit of the conditional expression (3), a higher-order positive distortion is caused, which is not preferable. Conditional expression (3)
Is more preferably set to 0.2. If the upper limit of conditional expression (4) is exceeded, the Petzval sum will be insufficiently corrected, and the flatness of the image will be degraded. More preferably, the upper limit of condition (4) should be set at 0.06.
On the other hand, when the value goes below the lower limit of the conditional expression (4), the occurrence of positive distortion becomes large, and it becomes difficult to perform a satisfactory correction.

If the upper limit of conditional expression (5) is exceeded, the telephoto ratio of the reverse telephoto system formed by the third lens unit and the second lens unit becomes large, which leads to an increase in the length of the third lens unit. The amount of positive distortion in the
It is not preferable because it becomes difficult to correct negative distortion generated in the second and fourth lens groups. More preferably, the upper limit of condition (5) should be set at 0.2. On the other hand, if the lower limit of conditional expression (5) is exceeded, higher-order spherical aberration and coma will occur, which leads to deterioration of the image, which is not preferable. More preferably, the lower limit to condition (5) should be set at 0.1. If the upper limit of conditional expression (6) is exceeded, the system lengthens and the lens diameter increases, which is not preferable. More preferably, the upper limit of condition (6) should be set at 0.1. On the other hand, if the lower limit of conditional expression (6) is exceeded, higher-order spherical aberration and coma will occur, which leads to deterioration of the image, which is not preferable.

In the present invention, (7) 0.7 <Eφ / (Hi + 0.2 × TT × tan)
It is preferable to satisfy the condition of (sin ^-1 (NA)) <1.1. Here, Eφ: maximum effective diameter of a lens constituting the projection optical system Hi: maximum image height on the second object NA: maximum image-side numerical aperture of the projection optical system

Conditional expression (7) defines a scale factor in a direction orthogonal to the optical axis to realize sufficient optical performance in the projection optical system of the present invention. When the value exceeds the upper limit of conditional expression (7), the lens diameter becomes large with respect to the total length, the first, third, or fourth lens group which is a positive lens group becomes large, and the space of other lens groups becomes large. As a result, it becomes impossible to realize a lens arrangement sufficient for aberration correction, and it is not possible to achieve sufficient optical performance. More preferably, the upper limit to condition (7) should be set at 1.0. Conversely, if the lower limit of conditional expression (7) is exceeded, the power of the first, third, or fourth lens group, which is the positive lens group, becomes larger than that of the second lens group, which has negative power. It is not preferable because spherical aberration, coma and distortion are particularly deteriorated and sufficient optical performance cannot be achieved. More preferably, the lower limit of condition (7) should be set at 0.8.

The above-described projection optical system is incorporated in an exposure apparatus for manufacturing a semiconductor device by transferring a circuit pattern on a projection original onto a photosensitive substrate. At that time, as the light source used for the illumination optical system that illuminates the circuit pattern on the projection original, a light source that emits light in the ultraviolet region was used.
The light beam from this light source is configured to be narrower,
It is preferable that each lens constituting the projection optical system is formed of a single glass material.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a sequential exposure type exposure apparatus according to a first embodiment of the exposure apparatus according to the present invention,
FIG. 2 shows a scanning type exposure apparatus according to the second embodiment. Both exposure apparatuses are used in an exposure process when forming a circuit pattern of a device such as an integrated circuit element or a liquid crystal panel. First, in the first embodiment of FIG. 1, a reticle R (first object) as a projection original on which a predetermined circuit pattern is drawn is arranged on the object plane of the projection optical system PL. A wafer W (second object) as a photosensitive substrate is arranged on the image plane of. Here, reticle R is held on reticle stage RS, and wafer W is held on wafer stage WS movable at least in the XY directions orthogonal to the optical axis of projection optical system PL. Further, an illumination optical system IL for uniformly illuminating the illumination area IA of the reticle R with ultraviolet exposure light is disposed above the reticle R (on the Z direction side). In this embodiment, the illumination optical system IL includes a light source (not shown) that emits light in the ultraviolet region, that is, a KrF excimer laser (λ = 248n).
m), and Kr is included in the illumination optical system IL.
A filter (not shown) for narrowing the spontaneous emission from the F excimer laser is provided. With the above configuration,
The exposure light supplied from the illumination optical system IL uniformly illuminates the illumination area IA on the reticle R. The exposure light that has passed through the reticle R forms a light source image at the position of the aperture stop AS of the projection optical system PL. That is, the reticle R is Koehler-illuminated by the illumination optical system IL. The illumination area IA of the reticle R is provided in the exposure area EA on the wafer W.
Is formed, whereby the circuit pattern of the reticle R is transferred to the wafer W.

Next, in the second embodiment of FIG. 2, the point that the reticle stage RS for holding the reticle R and the wafer stage WS for holding the wafer W scan in opposite directions during exposure is shown in FIG. It is different from the example. Thus, the wafer W is scanned and exposed to the image of the circuit pattern on the reticle R. Projection optical system PL in both embodiments
The following configuration is employed.
Then, a semiconductor device is manufactured by including a step of illuminating the circuit pattern drawn on the reticle R by the illumination optical system IL and a step of transferring an image of the circuit pattern to the wafer W using the projection optical system PL. Things.
In each of the projection optical systems PL of both embodiments, the first object side (the reticle R side) and the second object side (the wafer W side)
It is substantially telecentric and has a reduction factor. Further, in both of the above embodiments, the case where the wafer W is arranged as the second object has been described. However, when manufacturing a liquid crystal panel, a glass plate is arranged as the second object.

FIG. 3 shows a first embodiment of the projection optical system according to the present invention.
FIG. 6 shows an embodiment, and FIG. 6 shows a second embodiment. Both projection optical systems project an image of a pattern on the reticle R as the first object onto the wafer W as the second object, and the first optical system having positive power in order from the reticle R side.
It comprises a lens group G ₁ , a second lens group G ₂ having negative power, a third lens group G ₃ having positive power, and a fourth lens group G ₄ having positive power. The aperture stop AS is disposed in the fourth lens group G _4.

In the first embodiment of the projection optical system shown in FIG. 3, the first lens group G ₁ includes a plano-convex lens L ₁₁ , a biconvex lens L ₁₂ having a flat surface facing the reticle R side, and a convex surface facing the reticle R side. Negative meniscus lens L ₁₃ , biconvex lens L ₁₄ ,
And a bi-convex lens L _15. The second lens group G ₂ includes a negative meniscus lens L ₂₁ having a convex surface facing the reticle R side, a biconvex lens L ₂₂ , a negative meniscus lens L ₂₃ having a convex surface facing the reticle R side, a biconcave lens L ₂₄ , and a biconcave lens. L ₂₅ and a biconcave lens L ₂₆ . The third lens group G ₃ includes a positive meniscus lens L ₃₁ having a convex surface facing the wafer W, a negative meniscus lens L ₃₂ having a convex surface facing the wafer W, and a positive meniscus lens having a convex surface facing the wafer W. L _33, a biconvex lens L _34, a biconvex lens L _35. The fourth lens group G ₄ is
A positive meniscus lens L ₄₁ having a convex surface facing the reticle R side, a negative meniscus lens L ₄₂ having a convex surface facing the reticle R side, a negative meniscus lens L ₄₃ having a convex surface facing the reticle R side, a biconcave lens L ₄₄ , A negative meniscus lens L ₄₅ having a convex surface facing the wafer W side, a positive meniscus lens L ₄₆ having a convex surface facing the wafer W side, a positive meniscus lens L ₄₇ having a convex surface facing the wafer W side, a biconvex lens L ₄₈ , Wafer W
Negative meniscus lens L ₄₉ , biconvex lens L ₄₁₀ with a convex surface facing the side, positive meniscus lens L ₄₁₁ with a convex surface facing the reticle R side, positive meniscus lens L ₄₁₂ with a convex surface facing the reticle R side, reticle R A positive meniscus lens L ₄₁₃ having a convex surface facing the side, a negative meniscus lens L ₄₁₄ having a convex surface facing the reticle R side, and a positive meniscus lens L ₄₁₅ having a convex surface facing the reticle R side.

In the second embodiment of the projection optical system shown in FIG. 6, the first lens group G ₁ includes a plano-convex lens L ₁₁ , a bi-convex lens L ₁₂ , and a bi-convex lens L
_13. A positive meniscus lens L having a convex surface facing the wafer W side
_14, a biconvex lens L _15. The second lens group G ₂ includes a negative meniscus lens L ₂₁ having a convex surface facing the reticle R side,
Biconvex lens L _22, a negative meniscus lens L ₂₃ with a convex surface facing the reticle R side, a biconcave lens L _24, a biconcave lens L _25,
Consisting of a double-concave lens L _26. The third lens group G ₃ includes a positive meniscus lens L ₃₁ having a convex surface facing the wafer W, a negative meniscus lens L ₃₂ having a convex surface facing the wafer W, and a positive meniscus lens having a convex surface facing the wafer W. L _33, a biconvex lens L _34, a biconvex lens L _35. Fourth lens group G ₄
Are a positive meniscus lens L ₄₁ having a convex surface facing the reticle R side, a negative meniscus lens L ₄₂ having a convex surface facing the reticle R side, a negative meniscus lens L ₄₃ having a convex surface facing the reticle R side, and a biconcave lens L. ₄₄ , a negative meniscus lens L ₄₅ having a convex surface facing the wafer W side, a positive meniscus lens L ₄₆ having a convex surface facing the wafer W side, a positive meniscus lens L ₄₇ having a convex surface facing the wafer W side, and a biconvex lens L ₄₈ , wafer W
The negative meniscus lens L ₄₉ with the convex surface facing the reticle R, the positive meniscus lens L ₄₁₀ with the convex surface facing the reticle R side, the positive meniscus lens L ₄₁₁ with the convex surface facing the reticle R side, and the convex surface on the reticle R side. Positive meniscus lens L ₄₁₂ , a positive meniscus lens L ₄₁₃ having a convex surface facing the reticle R side, a negative meniscus lens L ₄₁₄ having a convex surface facing the reticle R side, and a positive meniscus having a convex surface facing the reticle R side. It consists of a lens _L415 .

Tables 1 and 2 below show the specifications of the first and second embodiments of the projection optical system and the conditional expressions (1) to (2), respectively.
The values of the parameters in (7) are shown. In [Lens Specifications] of both tables, the first column No is the number of each lens surface from the reticle R side, the second column r is the radius of curvature of each lens surface, and the third column d is each lens surface and the next lens. The distance on the optical axis from the surface, the fourth column shows the lens number. Each lens is made of a single glass material, ie, synthetic quartz (SiO ₂ ), and has a refractive index n of synthetic quartz with respect to the wavelength (248 nm) of a KrF excimer laser.
Is n = 1.50839.

[0021]

[Table 1] [Main specifications] Maximum object height: 79.2 Image side maximum numerical aperture: 0.70 [Lens specifications] Nord 0 ∞ 126.823 R 1 ∞ 13.000 L ₁₁ 2 -1219.009 1.000 3 463.352 19.469 L _{12 4 -40422.243 1.000 5 351.283 13.000 L} 13 6 259.852 9.209 7 425.616 25.541 L 14 8 -764.955 1.000 9 281.989 24.905 L 15 10 -4520.262 1.000 11 228.960 19.093 L 21 12 118.583 17.799 13 296.301 24.435 L 22 14 -749.157 1.000 15 23316.390 13.655 L ₂₃ 16 147.258 43.556 17 -232.667 13.000 L ₂₄ 18 224.059 16.164 19 -262.796 13.000 L ₂₅ 20 325.775 14.189 21 -338.099 13.000 L ₂₆ 22 790.196 31.754 23 -1533.927 25.522 L ₃₁ 24 -241.722 10.866 25 -169.181 39.937 L ₃₂ 26 -213.872 1.000 27 -1638.209 26.854 L ₃₃ 28 -333.782 1.000 29 789.230 30.098 L ₃₄ 30 -750.984 1.000 31 510.222 36.138 L ₃₅ 32 -774.798 10.810 33 305.627 25.875 L ₄₁ 34 876.606 16.099 35 229.581 38.445 L ₄₂ 36 150.286 16.442 L ₄₃ 38 156.609 43.175 39 -211.698 22.545 L ₄₄ 40 563.805 42.578 41 -173.000 22.143 L ₄₅ 42 -1009.618 10.000 43 -611.265 29.381 L ₄₆ 44 -213.804 1.000 45-10.535 AS 46 -3708.114 26.027 L ₄₇ 47 -390.735 1.000 48 403.873 52.274 L ₄₈ 49 -403.387 12.998 50 -275.993 23.359 L ₄₉ 51 -40 2.853 1.000 52 381.074 33.562 L ₄₁₀ 53 -134 10.0.520 1.000 54 200.594 34.891 L ₄₁₁ 55 456.048 1.000 56 172.868 27.630 L ₄₁₂ 57 282.240 1.000 58 130.675 36.950 L ₄₁₃ 59 331.635 6.383 60 521.082 14.270 L ₄₁₄ 61 78.027 20.63 L ₄₁₅ 63 660.673 11.475 64 ∞ W [Conditional value] (1) | En | /TT=3.077 (2) β = −0.167 (3) F1 / TT = 0.274 (4) −F2 / TT = 0.047 (5) F3 / TT = 0.148 (6) F4 / TT = 0.0082 (7) Eφ / (Hi + 0.2 × TT × tan (sin ⁻¹ (NA)) = 0.954

[0022]

[Table 2] [Main specifications] Maximum object height: 79.2 Image side maximum numerical aperture: 0.70 [Lens specifications] Nord 0 ∞ 60.000 R 1 ∞ 13.000 L ₁₁ 2 -4229.212 76.768 3 1500.665 16.860 L _{12 4 -1016.232 1.000 5 919.561 15.569 L} 13 6 -3600.448 2.541 7 -2556.320 15.474 L 14 8 -575.763 1.000 9 366.596 22.829 L 15 10 -3581.778 1.000 11 206.228 19.957 L 21 12 134.873 13.355 13 223.066 27.065 L 22 14 -832.483 16.171 15 1720.345 20.318 L ₂₃ 16 114.539 25.717 17 -283.906 17.623 L ₂₄ 18 211.304 18.680 19 -232.392 14.352 L ₂₅ 20 363.497 16.129 21 -239.391 13.224 L ₂₆ 22 2648.837 32.386 23 614.245 26.417 L ₃₁ 24 -195.498 6.134 25 -170.472 39.937 L _32. 26 -207.715 1.012 27 -1745.615 25.811 L ₃₃ 28 -348.534 1.013 29 689.697 29.236 L ₃₄ 30 -904.004 5.211 31 397.101 35.526 L ₃₅ 32 -1409.856 2.186 33 317.695 26.830 L ₄₁ 34 1188.840 13.182 35 241.321 38.445 L ₄₂ 36 153.969 14.992 37 256.132 14.145 L ₄₃ 38 152.085 47.741 39 -206.732 36.268 L ₄₄ 40 604.352 42.121 41 -174.493 22.599 L ₄₅ 42 -845.769 10.000 43 -553.322 29.239 L ₄₆ 44 -205.969 1.000 45-10.535 AS 46 -3783.006 24.943 L ₄₇ 47 -401.149 1.000 48 372.277 49.558 L ₄₈ 49 -453.455 13.767 50 -283.932 _{23.359 L 49 51 -428.362 1.000 52 340.205} 33.144 L 410 53 6649.009 1.000 54 216.001 32.687 L 411 55 549.478 1.000 56 173.858 26.771 L 412 57 283.739 1.000 58 133.099 36.533 L 413 59 376.281 6.027 60 625.841 13.357 L 414 61 86.661 20.071 62 95.803 63.457 L ₄₁₅ 63 616.803 10.728 64 ∞ W [Conditional value] (1) | En | /TT=3.077 (2) β = −0.167 (3) F1 / TT = 0.207 (4) −F2 / TT = 0.056 (5) F3 / TT = 0.145 (6) F4 / TT = 0.080 (7) Eφ / (Hi + 0.2 × TT × tan (sin ⁻¹ (NA)) = 0.925

FIG. 4 shows a first embodiment of the projection optical system.
FIG. 5 shows spherical aberration, astigmatism, and distortion, and FIG. 5 shows lateral aberration. Similarly, FIG. 7 shows spherical aberration, astigmatism, and distortion for the second embodiment of the projection optical system.
Shows lateral aberration. In each aberration diagram, NA indicates the image-side maximum numerical aperture, and Y indicates the image height. In the astigmatism diagram, a broken line indicates a meridional image plane, and a solid line indicates a sagittal image plane. In the transverse aberration diagram, (A) shows the transverse aberration of the ray in the meridional plane,
(B) shows the lateral aberration of the light ray in the sagittal plane in the sagittal direction. As is clear from the aberration diagrams, it is understood that both embodiments have excellent imaging performance by adopting a required lens configuration and satisfying the above-mentioned conditional expressions.

[0024]

As described above, according to the present invention, a projection optical system having a sufficiently wide exposure range, a sufficiently large numerical aperture, and a sufficiently suppressed enlargement of the lens outer diameter, And a method for manufacturing a semiconductor device using the exposure apparatus.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a first embodiment of an exposure apparatus.

FIG. 2 is a perspective view showing a second embodiment of the exposure apparatus.

FIG. 3 is a configuration diagram showing a first embodiment of a projection optical system.

FIG. 4 is a diagram showing spherical aberration, astigmatism, and distortion of the first embodiment of the projection optical system.

FIG. 5 is a lateral aberration diagram of the first embodiment of the projection optical system.

FIG. 6 is a configuration diagram showing a second embodiment of the projection optical system.

FIG. 7 is a diagram showing spherical aberration, astigmatism, and distortion of a second embodiment of the projection optical system;

FIG. 8 is a lateral aberration diagram of the second embodiment of the projection optical system.

[Explanation of symbols]

IL ... illumination optical system R ... reticle IA ... illumination region RS ... reticle stage PL ... projection optical system AS ... aperture stop W ... wafer EA ... exposed region WS ... wafer stage G ₁ ~G ₄ ... lens L ₁₁ ~L ₄₁₅ ... lens

Claims (8)

[Claims] 1. A projection optical system for projecting an image of a first object onto a second object, comprising: a first lens group having a positive power and a second lens group having a negative power in order from the first object side. And a third lens group having a positive power and a fourth lens group having a positive power, and satisfying the following condition. (1) | En | / TT> 2.5 (2) −0.179 <β <−0.125 where En: A paraxial light beam parallel to the optical axis is incident from the second object side of the projection optical system. In this case, the distance on the optical axis between the focal position formed by the entire projection optical system and the lens surface located closest to the first object in the projection optical system TT: distance between object images of the projection optical system β: projection This is the projection magnification of the optical system. 2. The projection optical system according to claim 1, wherein NA> 0.5, where NA is the maximum numerical aperture on the image side of the projection optical system. 3. The first lens group includes at least two positive lenses, the second lens group includes at least three negative lenses, the third lens group includes at least two positive lenses, 3. The projection optical system according to claim 1, wherein the fourth lens group includes at least five positive lenses and at least three negative lenses. 4. The method according to claim 1, wherein the following condition is satisfied.
The projection optical system as described in the above. (3) 0.1 <F1 / TT <0.4 (4) 0.03 <-F2 / TT <0.07 (5) 0.05 <F3 / TT <0.3 (6) 0.04 < F4 / TT <0.2 where F1: focal length of the first lens group F2: focal length of the second lens group F3: focal length of the third lens group F4: focal length of the fourth lens group is there. 5. The projection optical system according to claim 1, wherein the following condition is satisfied. (7) 0.7 <Eφ / (Hi + 0.2 × TT × tan
(Sin ^-1 (NA)) <1.1 where Eφ: maximum effective diameter of a lens constituting the projection optical system Hi: maximum image height on the second object NA: maximum image-side numerical aperture of the projection optical system is there. 6. An illumination optical system for illuminating the first object, a first support member for supporting the first object, the projection optical system according to claim 1, and the second optical system. An exposure apparatus, comprising: a second support member that supports an object. 7. The illumination optical system includes a light source that emits light in an ultraviolet region, and a unit that narrows a light beam from the light source. The projection optical system is formed of a single glass material. The exposure apparatus according to claim 6, wherein: 8. A step of illuminating a circuit pattern drawn on the first object by an illumination optical system, and using the projection optical system according to claim 1 to form an image of the circuit pattern. Transferring to the second object.