JP2002118053A - Projection optical system, projection aligner provided with the projection optical system, and manufacturing method of device using the projection aligner - Google Patents

Abstract

(57) [Problem] To achieve image-side telecentricity over the entire exposure area, to achieve a sufficiently large numerical aperture (NA) and a wide exposure area, and to achieve a compact and high performance that can correct various aberrations extremely well. To provide a projection optical system. SOLUTION: In a projection optical system PL for projecting an image of a reticle R (first object) illuminated by an illumination optical device IS onto a wafer W (second object), the projection optical system PL is located near a pupil position in the optical system. Have aperture stops AS1 and AS2 for determining NA at a plurality of positions. The aperture stops AS1 and AS2 are
A ray passing through the center of the exit pupil is a wafer as a second object
It is arranged to be perpendicular to W, that is, to be telecentric on the second object side. Aperture stop A
At least one of S1 and AS2 is a variable aperture stop whose aperture size can be changed, and is movable in the optical axis direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection optical system for projecting an image of a first object onto a second object, and to a semiconductor device or a liquid crystal display device having the projection optical system. Exposure apparatus used for transferring a mask pattern onto a substrate in a lithography process, and a method of manufacturing a device (semiconductor element, imaging element, liquid crystal display element, thin film magnetic head, CCD element, etc.) using the exposure apparatus It is about.

[0002]

2. Description of the Related Art When manufacturing a semiconductor device, an image of a reticle pattern as a mask is projected onto a wafer (or a glass plate or the like) coated with a resist through a projection optical system.
A projection exposure apparatus of a batch exposure type (stepper or the like) for transferring onto the top or a scanning exposure type such as a step-and-scan method is used. As the pattern of a semiconductor integrated circuit or the like to be transferred becomes finer, it is desired that a projection optical system provided in such an exposure apparatus be improved particularly in resolution. In order to improve the resolving power of the projection optical system, the exposure wavelength must be made shorter or the numerical aperture (N
It is conceivable to increase A).

In recent years, exposure light has been changed from g-line (wavelength 436 nm) of a mercury lamp to i-line (wavelength 365 n).
m), and more recently light sources with shorter wavelength light, such as KrF (wavelength 248 nm), and A
An excimer laser such as rF (wavelength 193 nm) is used, and the wavelength of exposure light is being shortened. Also, as for the numerical aperture (NA), the numerical aperture (NA) has been increased, and the numerical aperture (NA) has been reduced to 0.1.
More than six projection optical systems have been proposed.

[0004] Further, as the transfer pattern becomes finer, the demand for reducing the image distortion as well as improving the resolving power in the projection optical system has become more severe. Here, the image distortion is caused not only by distortion (distortion aberration) caused by the projection optical system but also by warpage of a wafer printed on the image side of the projection optical system. In order to reduce the influence on the image distortion due to the warpage of the wafer, an optical system in which the exit pupil position on the image side of the projection optical system is located far, that is, a so-called image-side telecentric optical system has been used.
Among the image-side telecentric projection optical systems, examples in which distortion is satisfactorily corrected while ensuring a high NA are disclosed in JP-A-8-166540 and JP-A-8-190.
No. 047 and the like.

[0005]

However, when the numerical aperture (NA) becomes large, the amount of pupil aberration becomes so large that it cannot be ignored. With only one aperture stop, the image side telecentricity is obtained substantially within the exposure area. I was unable to do it. Furthermore, in order to make the numerical aperture (NA) of the projection optical system variable, if a variable aperture stop is provided and the numerical aperture (NA) is changed by the variable aperture stop, the image side telecentric in the exposure area due to pupil aberration. Was no longer available.

Among the pupil aberrations, an attempt has already been made to reduce the image-side telecentricity due to the curvature of the pupil's field of view. No. 6,086,045. However, among the pupil aberrations, it has been an inevitable problem that the image-side telecentricity is deteriorated by the pupil coma aberration. Therefore, when the numerical aperture (NA) is changed, the telecentricity and the illuminance uniformity on the image plane deteriorate over the entire exposure area, and there is a disadvantage that the projection area cannot be made very wide.

The present invention has been made in view of such a problem, and achieves so-called image-side telecentricity in which a ray passing through the center of an exit pupil is perpendicular to a second object over the entire exposure area. It is an object of the present invention to provide a compact and high-performance projection optical system capable of correcting various aberrations extremely well while securing a sufficiently large numerical aperture (NA) and a wide exposure area. Still another object of the present invention is to provide an exposure apparatus having the above-described projection optical system and a method for manufacturing a device using the exposure apparatus.

[0008]

According to one aspect of the present invention, there is provided a projection optical system for projecting an image of a first object onto a second object. An aperture stop for determining a numerical aperture is provided at a plurality of positions in the projection optical system, and the aperture stops provided at the plurality of positions are arranged to be telecentric on the second object side. A projection optical system is provided. By arranging the aperture stops at a plurality of positions, it becomes possible to minimize the deterioration of the telecentricity on the second object side due to coma of the pupil, and achieve the telecentricity on the second object side over the entire exposure area. A sufficiently large numerical aperture (NA) and a wide exposure area can be secured. Further, since it is not necessary to determine the correction of the pupil aberration to the limit, it is possible to correct various aberrations very well without increasing the length of the optical system.
A compact and high-performance projection optical system can be provided.

The present invention is directed to a second aspect of the present invention.
When the numerical aperture on the object side is NA, it is suitable for a projection optical system that satisfies the condition of NA> 0.6. In such an optical system, the pupil aberration is a non-negligible amount.
Especially effective. In addition, as described in claim 3, the second
The difference in the numerical aperture of the light beam reaching the exposure area on the object is ΔN
When A is set, it is preferable that the configuration is such that the condition of ΔNA <0.007 is satisfied. If this condition is not satisfied, image-side telecentricity cannot be obtained over the entire exposure area, and image distortion due to wafer warpage increases. Also, if the difference in numerical aperture is large, uniformity of the line width of the pattern projected on the substrate cannot be obtained. Furthermore, it is preferable that at least one of the aperture stops provided at the plurality of positions is configured such that the size of the aperture can be changed, thereby providing a numerical aperture (N).
A) can realize a variable projection optical system.

According to another aspect of the present invention, there is provided a projection optical system for projecting an image of a first object onto a second object, wherein the projection optical system includes a plurality of projection optical systems. An aperture stop for determining a numerical aperture is provided at a position, and at least one of the aperture stops provided at the plurality of positions is capable of changing the size of the opening, and changing the size of the opening. A projection optical system is provided, wherein at least one of the aperture stops can be changed in the optical axis direction so that the aperture stop becomes telecentric toward the second object. According to such a configuration, when the numerical aperture (NA) is changed, the aperture stop can be moved along the optical axis to optimize the image-side telecentricity. In particular, when there is a pupil curvature aberration, the position of the aperture stop can be changed along the curved pupil surface with a change in the numerical aperture (NA), which is effective.

According to a sixth aspect of the present invention, at least two of the aperture stops provided at the plurality of positions may be formed of the same member. According to such a configuration, it is possible to provide a function of a plurality of aperture stops with one member, and the number of components can be reduced, so that assembly is easy and cost is reduced.

According to another aspect of the present invention, a stage system for positioning the projection optical system, a mask as the first object, and a substrate as the second object as described in claim 7. An illumination optical system for illuminating the mask;
An exposure apparatus, wherein an image of the pattern of the mask is projected onto the substrate via the projection optical system under an exposure energy beam from the illumination optical system. The projection optical system has a large numerical aperture (N
Since the image side telecentric is achieved in A), a high resolution can be obtained, and the projection magnification does not change even if the substrate is warped. Also, because a wide exposure area can be obtained,
A large chip pattern can be exposed at a time.

According to still another aspect of the present invention, there is provided a method of manufacturing a device using the exposure apparatus, wherein a first material is coated on the substrate.
A step of projecting an image of the pattern of the mask onto the substrate via the projection optical system; a third step of developing the photosensitive material on the substrate; And a fourth step of forming a predetermined circuit pattern on the substrate as a mask. According to such a configuration, a circuit pattern for a device can be formed on a substrate with high resolution,
Good devices can be manufactured.

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings. In the following description and the accompanying drawings, components having substantially the same functions and configurations are denoted by the same reference numerals, and redundant description is omitted.

In this embodiment, the present invention is applied to a projection optical system of a projection exposure apparatus. FIG. 1 shows the projection optical system P of this example.
3 shows a projection exposure apparatus provided with L. In FIG. 1, a reticle R (first object) as a projection master on which a predetermined circuit pattern is formed is arranged on the object plane of the projection optical system PL.
On the image plane of the projection optical system PL, a wafer W (second object) coated with a photoresist as a substrate is arranged. Reticle R is held on reticle stage RS,
The wafer W is held on a wafer stage WS, and an illumination optical device IS for uniformly illuminating the reticle R is disposed above the reticle R.

The projection optical system PL includes an aperture stop AS for determining a numerical aperture (NA) at two positions near the pupil position.
1 and AS2, the reticle R side and the wafer W
On the side, it is virtually telecentric.
The illumination optical device IS includes an exposure light source composed of a KrF excimer laser (wavelength 248 nm), a fly-eye lens for equalizing the illuminance distribution of the exposure light, an illumination system aperture stop, a variable field stop (reticle blind), and It is composed of a condenser lens system and the like.

Exposure light supplied from the illumination optical device IS illuminates the reticle R, and an image of a light source in the illumination optical device IS is formed at a pupil position of the projection optical system PL, so-called Koehler illumination is performed. Then, the image of the pattern of the reticle R illuminated by Koehler is reduced at the projection magnification via the projection optical system PL, is exposed on the wafer W, and is transferred.

Next, the configuration of the projection optical system PL according to the embodiment will be described in detail. FIG. 2 is a lens cross-sectional view of the projection optical system PL. As shown in FIG. 2, the projection optical system PL
It has two aperture stops AS1 and AS2 for determining NA at two positions near the pupil position. Aperture stop AS1, AS2
Are variable aperture stops whose aperture size can be changed, and are movable in the optical axis direction. Then, the two aperture stops AS1 and AS2 allow the light passing through the center of the exit pupil to be perpendicular to the wafer W as the second object, that is, to make the projection optical system PL image-side telecentric. It is configured.

FIGS. 3 and 4 show lens data of the projection optical system PL. FIG. 4 shows a continuation of FIG.
The two are combined to form a series of lens data. Figures 3 and 4
, The serial numbers from 1 to 56 are numbers indicating the surface of each lens. The serial numbers are assigned in order from the reticle R side as the first object to the wafer W side as the second object.
r is the radius of curvature of each lens surface, d is the distance between each lens surface, and the glass material is all quartz. The refractive index of quartz at a wavelength of 248 nm of the light source is 1.50839. In this projection optical system PL, the maximum numerical aperture (NA) is 0.75.
The projection distance d0, which is the distance from the reticle R to the first surface of the serial number, is 71.397 mm, the magnification β is 1/4, and the serial number is 5
The back focal length Bf, which is the distance from the sixth surface to the wafer W, is 12.000 mm, and the exposure area of the second object on the wafer W is a circle having a diameter of 27.44 mm.

In the lens data, the 10th surface and the 32nd
The numbered surface uses an aspherical surface, realizing a high NA of 0.75. FIG. 5 shows values of respective coefficients when the aspherical shape is defined by the following equation. Definition of aspheric surface

[0021]

(Equation 1)

Here, Z: sag of the plane parallel to the optical axis c: curvature at the vertex of the plane κ: cone coefficient (κ = 0: spherical surface) h: distance from the optical axis

The two aperture stops AS1 and AS2 are provided between the surfaces 42 and 43 of the serial number. The operation and effect of these two aperture stops AS1 and AS2 will be described below. Maximum numerical aperture from the optical axis of the object plane
A ray when the ray is traced so as to have (NA) is defined as Lo. Upper and lower rays when rays are traced from the maximum height position of the object plane to have the maximum numerical aperture (NA) are Lpu and Lpl, respectively. Lpu is the upper frame, L
pl corresponds to the light ray on the lower coma side. As described above, since the magnification β is 1/4 and the exposure area is a circle having a diameter of 27.44 mm, the maximum value of the object height is 54.88 mm.

The heights of the light beams Lo, Lpu and Lpl are defined as ho, hpu and hpl, respectively. Here, the height of the light beam is a distance from the optical axis. FIG.
The figure shows the height of each light ray on the surface before and after the aperture stop at the maximum numerical aperture (NA) of 0.75. The front and rear surfaces of the aperture stop are the 42th and 43rd surfaces of the serial number,
A tangent plane that is tangent on the optical axis and perpendicular to the optical axis. FIG.
Is a graph of the height of each light ray in FIG. 6, in which the horizontal axis represents the distance from the surface 42 and the vertical axis represents the ray height.

In general, it is ideal that the aperture stop is located at a position where the chief ray cuts the optical axis.
In a projection optical system having a numerical aperture (NA), a ray Lo when a ray is traced so as to have a maximum numerical aperture (NA) from the optical axis of the object plane, and a maximum numerical aperture based on the position of the maximum height of the object plane.
It is desirable to determine the numerical aperture (NA) at a position where the light rays Lpu and Lpl on the upper frame side and the lower frame side at the time of ray tracing so as to have (NA) have the same height. That is, FIG.
In, it is desirable to determine the numerical aperture at the position where three line segments drawn as ho, hpu and hpl intersect.
However, looking at FIG. 7, these three line segments do not intersect at one point. This is due to pupil aberration. If the pupil aberration correction is dared to solve this problem, the size of the optical system is increased and the manufacturing cost is increased.

Therefore, an aperture stop for determining the numerical aperture (NA) is arranged at a plurality of positions. As a result, it is possible to minimize deterioration of image-side telecentricity due to coma of the pupil. In the case shown in FIG. 7, if an optimal aperture stop is set, the intersection of ho and hpu, and ho and hpl
It is preferable to dispose an aperture stop having a size corresponding to each ray height at the position of the intersection of. That is, the diameter 24 is located at a distance of 18.582 mm from the surface of the serial number 42 toward the second object.
A 0.15 mm aperture stop AS1, a diameter 246.2 at a position 44.444 mm from the surface of the serial number 42 toward the second object.
Two aperture stops AS2 and 4 mm are provided. FIG. 8 is an optical path diagram before and after the aperture stop when the aperture stop is arranged as described above. In FIG. 8, S42, S43
Are the tangent plane of the No. 42 surface and the tangent plane of the No. 43 surface, respectively.

When the two aperture stops are arranged as described above, the numerical aperture on the second object side determined by the uppermost and lowermost peripheral rays with respect to the ray perpendicular to the second object, ie, the principal ray, NApu and NApl, respectively. This NApu
FIG. 9 shows the calculated values of NApl and NApl over the entire exposure area on the second object side. Referring to FIG. 9, the numerical aperture in the entire exposure area is equal to or very close to 0.75.
From FIG. 9, it is understood that when considering the numerical aperture of the light beam reaching an arbitrary point in the exposure area and the difference is ΔNA, ΔNA is suppressed to a very small value, that is, the variation in the numerical aperture is extremely small. it can. This can be rephrased as forming a good telecentric optical system on the second object side. By arranging a plurality of aperture stops in this way, it is possible to minimize the difference in numerical aperture (NA) over the entire exposure area.

Next, a case where the size of the aperture of the aperture stop is reduced to a numerical aperture (NA) of 0.5 is examined in the same manner as in the case of the numerical aperture (NA) of 0.75. . FIG.
0 indicates the height of each ray on the plane before and after the aperture stop at a numerical aperture (NA) of 0.5. FIG.
Is a graph of the height of each ray of light, and the horizontal axis is 42
The distance from the surface and the vertical axis is the ray height. Again, Lo,
The definitions of Lpu, Lpl, ho, hpu, and hpl are the same as in the case of the numerical aperture (NA) of 0.75, and the numerical aperture (N
It is sufficient to replace only A) with 0.5.

As shown in FIG. 11, ho, due to pupil aberration,
The three line segments drawn as hpu and hpl do not intersect at one point. Therefore, if an optimal aperture stop is set, it can be set as follows, in the same manner as in the case of a numerical aperture (NA) of 0.75. From the intersection of ho and hpu, an aperture stop AS1 having a diameter of 150.7 mm is arranged at a position of 6.418 mm from the surface of the serial number 42 on the second object side, and ho and h
from the intersection of pl to the second object side from the surface of the serial number 42
An aperture stop AS2 having a diameter of 152.9 mm is arranged at a position of 4.397 mm. FIG. 12 is an optical path diagram before and after the aperture stop when the aperture stop is arranged as described above. In FIG. 12, S42 and S43 are tangent planes of the No. 42 surface, respectively.
This is the tangent plane of the third surface.

When the two aperture stops are arranged as described above, the numerical aperture on the side of the second object determined by the uppermost and lowermost peripheral rays with respect to the ray perpendicular to the second object, ie, the principal ray, NApu and NApl, respectively. This NApu
FIG. 13 shows the calculated values of NApl and NApl over the entire exposure area on the second object side. Referring to FIG. 13, the numerical aperture in the entire exposure area is equal to or very close to 0.5. From FIG. 13, it is understood that when considering the numerical aperture of the light beam reaching an arbitrary point in the exposure region and the difference is ΔNA, ΔNA is suppressed to a very small value, that is, the variation of the numerical aperture is extremely small. it can. This can be rephrased as forming a good telecentric optical system on the second object side. Thus, by arranging a plurality of aperture stops, the numerical aperture (N
The difference of A) can be minimized.

As can be seen from the above and FIGS. 8 and 12, when the numerical aperture (NA) is 0.75 as compared with the case where the numerical aperture (NA) is 0.5,
The difference between the distance between the two aperture stops and the diameter is widened. This is because the larger the numerical aperture, the larger the pupil aberration. Therefore, in a projection optical system having a large numerical aperture (NA), it is particularly effective to have a plurality of aperture stops.

In the above, the case where both the aperture stops AS1 and AS2 are variable aperture stops has been described. However, since at least one of the two aperture stops has a variable aperture stop mechanism, the projection with a variable numerical aperture (NA) is possible. An optical system can be realized. When only one aperture stop has a variable aperture stop mechanism, in the above example, it is desirable to apply the variable mechanism to the aperture stop AS1 close to the first object side in consideration of the pupil field curvature. In such a projection optical system having a variable numerical aperture (NA), the numerical aperture (NA) is changed, and at the same time, the aperture stop can be moved along the optical axis so that the image side telecentricity is optimized. It is desirable to be configured. Note that both AS1 and AS2 do not necessarily need to be movable in the optical axis direction, and depending on the characteristics of the projection optical system,
One of the two aperture stops may be configured to be movable in the optical axis direction.

Instead of disposing a plurality of aperture stops as described above, an equivalent effect can be obtained by disposing one thick aperture stop having different apertures in the optical axis direction on the first object side and the second object side. Is obtained. FIG. 14 shows an example. Aperture stop AS
Numeral 3 has a ring shape, a thickness H, and a tapered shape whose inner diameter changes from D1 to D2. Here, D1 and D2 are defined as the aperture stops AS1 and AS described above.
If the aperture is manufactured so as to be equal to the diameter of the aperture stop 2 and to be equal to the distance between these two aperture stops, one member can have the aperture stop function at two places. The aperture stop A
The inner diameter of S3 does not necessarily have to be tapered, but may be any shape that does not block the required light beams.

Next, an example of an operation for forming a predetermined circuit pattern on a wafer using the projection exposure apparatus of the above embodiment will be described with reference to FIG. First, in step 101 of FIG. 15, a metal film is deposited on one lot of wafers. In the next step 102, a photoresist is applied on the metal film on the one lot wafer. Thereafter, in step 103, using the exposure apparatus of FIG. 1 provided with the projection optical system PL of FIG. 2, the pattern image on the reticle R is transmitted through the projection optical system PL.
Exposure transfer is sequentially performed on each shot area on the wafer of the lot. Thereafter, in step 104, the photoresist on the one lot of the wafer is developed. Thereafter, in step 105, a circuit pattern corresponding to the pattern on the reticle R is formed in each shot area on each wafer by performing etching on one lot of wafers using the resist pattern as a mask. After that, a device such as a semiconductor element is manufactured by forming a circuit pattern of a further upper layer.

While the preferred embodiments of the present invention have been described with reference to the accompanying drawings, it goes without saying that the present invention is not limited to such examples. It is obvious that a person skilled in the art can come up with various changes or modifications within the scope of the technical idea described in the claims, and it is obvious that the technical scope of the present invention is not limited thereto. It is understood that it belongs to.

For example, in the above-described example, the case where the aperture stop is provided at two positions has been described. However, the present invention is not limited to this. The aperture stop may be provided at more positions according to the characteristics of the projection optical system. . In this case, the aperture stop shown in FIG. 14 may be provided with an aperture stop function at a greater number of locations. In the above example, a KrF excimer laser (wavelength 248) is used as a light source of the illumination optical device IS.
Although the example using (nm) has been described, the present invention is not limited to this. As a light source, an ArF excimer laser (wavelength 1)
93 nm), or _{F 2} laser (wavelength 158 nm),
Harmonics of YAG laser, i-line of mercury lamp (wavelength 365
nm) can also be used.

[0037]

As described in detail above, according to the present invention, the exposure is achieved by arranging an aperture stop for determining the numerical aperture (NA) at a plurality of positions so as to be telecentric on the second object side. Telecentricity of the second object side can be achieved over the entire area, and the projection magnification does not change even if the wafer is warped. In addition, since a sufficiently large numerical aperture (NA) and a wide exposure area can be secured, a large chip pattern can be exposed at a high resolution at a time. Further, since it is not necessary to determine the correction of the pupil aberration to the limit, it is possible to correct various aberrations very well without increasing the length of the optical system.
A compact and high-performance projection optical system can be provided.

Further, according to another aspect of the present invention, a projection optical system having a variable numerical aperture (NA) can be realized. At this time, the aperture stop is moved along the optical axis to achieve image side telecentricity. Can be optimized. Further, according to another aspect of the present invention, it is possible to provide an exposure apparatus capable of transferring a mask pattern image with high resolution onto a substrate without changing the projection magnification even when the substrate is warped,
It is possible to provide a method of manufacturing a device capable of forming an extremely fine circuit pattern in a wide exposure area on a substrate.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an exposure apparatus according to an embodiment of the present invention.

FIG. 2 is a lens cross-sectional view of the projection optical system according to the embodiment of the present invention.

FIG. 3 is a diagram showing numerical examples of lens data of the projection optical system according to the embodiment of the present invention.

FIG. 4 is a diagram showing a continuation of the lens data of FIG. 3;

FIG. 5 is a diagram showing values of respective aspherical surface coefficients of the aspherical surface of FIG.

FIG. 6 is a diagram showing the height of light rays on surfaces before and after an aperture stop at a numerical aperture (NA) of 0.75 of the projection optical system according to the embodiment of the present invention.

FIG. 7 is a graph showing the height of each light beam in FIG. 6;

FIG. 8 is an optical path diagram before and after the aperture stop when the aperture stop according to the embodiment of the present invention is arranged.

FIG. 9 is a diagram showing a numerical aperture in an entire exposure area of the projection optical system according to the embodiment of the present invention.

FIG. 10 is a diagram showing the height of light rays on surfaces before and after an aperture stop at a numerical aperture (NA) of 0.5 in the projection optical system according to the embodiment of the present invention.

FIG. 11 is a graph showing the height of each light beam in FIG. 10;

FIG. 12 is an optical path diagram before and after the aperture stop when the aperture stop according to the embodiment of the present invention is arranged.

FIG. 13 is a diagram illustrating a numerical aperture in an entire exposure area of the projection optical system according to the embodiment of the present invention.

FIG. 14 is an example of an aperture stop according to an embodiment of the present invention.

FIG. 15 is a flowchart illustrating an example of an operation of forming a circuit pattern using the exposure apparatus according to the embodiment of the present invention.

[Explanation of symbols]

 AS1, AS2, AS3 Aperture stop IS Illumination optical device PL Projection optical system R Reticle W Wafer

Continuation of the front page F term (reference) 2H087 KA21 NA02 PA15 PA17 PB20 QA01 QA05 QA13 QA21 QA25 QA33 QA41 QA46 RA05 RA12 RA32 UA03 5F046 BA03 CB05 CB25

Claims (8)

[Claims] 1. A projection optical system for projecting an image of a first object onto a second object, wherein an aperture stop for determining a numerical aperture is provided at a plurality of positions in the projection optical system. The projection optical system is characterized in that the aperture stop provided at the position (2) is arranged to be telecentric on the second object side. 2. The projection optical system according to claim 1, wherein, when the numerical aperture on the second object side is NA, a condition of NA> 0.6 is satisfied. 3. When ΔNA is a difference in numerical aperture of a light beam reaching an exposure area on the second object, ΔNA <0.0.
The projection optical system according to claim 1, wherein the condition of 07 is satisfied. 4. The projection according to claim 1, wherein at least one of the aperture stops provided at the plurality of positions has a variable aperture size. Optical system. 5. A projection optical system for projecting an image of a first object onto a second object, wherein an aperture stop for determining a numerical aperture is provided at a plurality of positions in the projection optical system. At least one of the aperture stops provided at the positions of the first and second aperture stops can change the size of the aperture, and the aperture stop can be telecentric toward the second object when the size of the opening is changed. At least one of the projection optical systems is capable of changing its position in the optical axis direction. 6. The projection optical system according to claim 1, wherein at least two of the aperture stops provided at the plurality of positions are made of the same member. 7. A projection optical system according to claim 1, a mask as said first object, and a stage system for positioning a substrate as said second object, and illuminating said mask. And an illumination optical system for projecting an image of the pattern of the mask onto the substrate via the projection optical system under an exposure energy beam from the illumination optical system. apparatus. 8. A method for manufacturing a device using the exposure apparatus according to claim 7, wherein a first step of applying a photosensitive material on the substrate and the projection optical system on the substrate are performed through the projection optical system. A second step of projecting an image of a mask pattern, a third step of developing the photosensitive material on the substrate, and a fourth step of forming a predetermined circuit pattern on the substrate using the developed photosensitive material as a mask. And a method of manufacturing a device.