JPH05275315A - Projection aligner - Google Patents

Abstract

PURPOSE:To enhance transfer accuracy by 5 constitution wherein an aperture member comprises a transmissive region for shaping the light beam emitted from a light source and a light shielding member formed in stripe while traversing the light transmissive region. CONSTITUTION:An aperture member 21 comprises a light transmissive region D for shaping the light beam emitted from a light source 11-13 and a light shielding member 24 formed in stripe while traversing the light transmissive region D. Preferably, the light shielding stripe member 24 is arranged in parallel with the parallel line pattern of a mask 18 and the light shielding member 24 can be formed by depositing a metallic material on a transparent member 23. Since such components of the light emitted from the light source as deteriorating contrast or focus depth of optical image are shielded by means of the aperture member, transfer accuracy can be enhanced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection exposure apparatus for forming a fine pattern required for manufacturing an LSI.

[0002]

2. Description of the Related Art FIG. 46 shows an optical system of a conventional projection exposure apparatus. A fly-eye lens 3 is arranged in front of the lamp house 1 via a mirror 2. An aperture member 4 is located in front of the fly-eye lens 3, and an exposure mask 8 on which a desired circuit pattern is formed is arranged via the condenser lenses 5 and 6 and a mirror 7. A wafer 10 is located in front of the mask 8 via a projection lens system 9. As shown in FIGS. 47 and 48, the aperture member 4 has a disc shape with a circular opening 4a formed in the center.

Light emitted from the lamp house 1 is reflected by the mirror 2
The fly-eye lens 3 is reached via the, and is divided into regions of individual lenses 3 a forming the fly-eye lens 3. The light passing through each lens 3a irradiates the entire exposure area of the mask 8 through the opening 4a of the aperture member 4, the condenser lens 5, the mirror 7 and the condenser lens 6, respectively. Therefore, on the surface of the mask 8, the lights from the individual lenses 3a of the fly-eye lens 3 overlap with each other, and uniform illumination is performed. The light thus passing through the mask 8 reaches the wafer 10 via the projection lens system 9 and thereby the wafer 1
The circuit pattern is printed on the surface of 0. It is known that the minimum resolution R in such a projection exposure apparatus is proportional to λ / NA, where λ is the wavelength used and NA is the numerical aperture of the optical system. Therefore, conventionally, the optical system is designed so that the numerical aperture NA is increased to improve the resolution of the projection exposure apparatus, which corresponds to the recent high integration of LSI.

[0004]

However, it is known that when the numerical aperture NA of the optical system is increased, the minimum resolution R is reduced, but the depth of focus DOF of the projection exposure apparatus is further reduced. This depth of focus DOF is proportional to λ / NA ² . For this reason, in the conventional projection exposure apparatus, there has been a problem that, when trying to improve the resolution, the depth of focus becomes small and the transfer accuracy deteriorates.

FIG. 49 shows a light source image formed on the pupil 9a of the projection lens system 9 when the circuit pattern of the mask 8 has a parallel line pattern near the resolution limit.
A light source image S ₀ by the 0th order light is formed at the center of the pupil 9a, and light source images S ₁ and S ₂ by the primary light are formed on the left and right sides of the light source image S ₀ , respectively. For example, the 0th-order light source image S ₀
The light L ₀ passing through the center point of the light source image interferes with the light L ₁ and L ₂ passing through the center points of the primary light source images S ₁ and S ₂ to form a pattern on the wafer 10. At this time, when the angle at which the lights L ₁ and L ₂ passing through the peripheral portion of the pupil 9a are incident on the wafer 10 is θ ₁ , the numerical aperture NA is represented by sin θ ₁ , so that the wafer 1
The greater the angle of incidence on 0, the more the depth of focus DOF deteriorates.

Therefore, in order to prevent the deterioration of the depth of focus DOF, Japanese Patent Application Laid-Open No. 61-91662 proposes a projection exposure apparatus using a ring-shaped aperture member. In this case, as shown in FIG. 50, each light source image S ₀
Lights L _{0 to} L ₂ passing through the central portion of S ₂ to S ₂ are blocked by the aperture member, that is, the pupil 9 near the resolution limit.
Since the light passing through the peripheral portion of a is blocked, the wafer 10
The angle of incidence θ _{2 on} is small, which results in a depth of focus D
OF is improved. However, in FIG. 50, the lights L ₄ and L ₅ of the primary light source images S ₁ and S ₂ among the lights L _{3 to} L ₅ that pass through the upper edge portions of the respective light source images S _{0 to} S ₂ fall outside the pupil 9a. It is blocked by the pupil 9a in order to pass. Therefore, the light L ₃ of the 0th-order light source image S ₀ cannot be focused on the wafer 10 and only contributes to the background illumination. Therefore, the contrast of the image is significantly deteriorated,
The transfer accuracy deteriorates.

Further, as shown in FIG. 51, considering the lights L _{6 to} L ₈ passing through the left portions of the respective light source images S _{0 to} S ₂ , of these lights, the light of the −1st-order light source image S ₂ is taken. Since L ₈ is blocked by the pupil 9 a, the light L ₆ of the 0th-order light source image S ₀ interferes with the light L ₇ of the + _1st- order light source image S _{1 to form} an image on the wafer 10. Similarly, the light passing through the shaded portion Q ₀ of the 0th-order light source image S ₀ interferes only with the light passing through the shaded portion Q ₁ of the + _1st- order light source image S ₁ .
On the other hand, the light passing through the shaded portion R ₀ on the right side of the 0th-order light source image S ₀ is −
It interferes only with the light passing through the shaded portion R ₂ of the primary light source image S ₂ .
That is, in these shaded areas Q ₀ , Q ₁ , R ₀ and R ₂ , one of the + 1st order light source image S ₁ and the −1st order light source image S ₂ cannot contribute to image formation.

As shown in FIG. 52, it is assumed that the mask 8 has a line-and-space circuit pattern in which the width of the light-shielding portion 8a and the width of the transmitting portion 8b are equal to each other. The amplitude T _{0 of} S ₀ is 0.5, and the amplitudes T ₁ and T ₂ of the +1 and −1st order light source images S ₁ and S ₂ are 0.63 / 2, respectively. These amplitudes T _{0 to} T ₂ are
In FIG. 51, the light source images S _{0 to} S ₂ are schematically represented as the thicknesses of the disks. Such an amplitude T ₀
In the case where all the light source images S _{0 to} S ₂ having T ₂ to T ₂ can contribute to the image formation, the amplitude E of the optical image on the wafer 10 is large and good, as shown in FIG. However, when one of the + 1st-order light source image S ₁ and the −1st-order light source image S ₂ cannot contribute to the image formation, the amplitude F of the optical image becomes small as indicated by the broken line, and the image contrast is reduced. to degrade.

54 and 55 show a Levenson type phase shift mask. By forming Cr light-shielding members 8d on the transparent substrate 8c at equal intervals in parallel with each other, transparent portions and light-shielding portions are alternately formed, and a phase shift member 8e made of SOG or the like is formed at every other transparent portion. ing. When such a phase shift mask is used, in the portion where the phase shift member 8e and the transparent substrate 8c are adjacent to each other on the plane pattern, the light transmitted through the phase shift member 8e and the transparent substrate 8c and only the transparent substrate 8c are transmitted. The light interferes and the light intensity becomes zero. Therefore, for example, when a positive resist is used, a deformed portion 10b of the pattern is generated on the wafer 10 as shown in FIG. 56, and the original patterns 10a formed by the light shielding member 8d are connected to each other. In this way, there is a problem that the transfer accuracy is deteriorated.

The present invention has been made to solve such a problem, and an object of the present invention is to provide a projection exposure apparatus capable of improving the transfer accuracy.

[0011]

A projection exposure apparatus according to claim 1 has a light source, a condenser lens system for irradiating light emitted from the light source onto a mask on which a circuit pattern is formed, and a condenser lens system passing through the mask. A projection lens system for condensing light on the wafer surface and an aperture member arranged between the light source and the condenser lens system are provided, and the aperture member is a transmissive region for shaping the light emitted from the light source and the transmissive region. And a light-shielding member formed in a band shape so as to cross the region.
In the projection exposure apparatus according to the second aspect, the aperture member has a light shielding member formed in a pincushion shape so as to cross the inside of the transmission region. In the projection exposure apparatus according to the third aspect, the aperture member has a light-shielding member formed in a spindle shape so as to cross the inside of the transmission region. In the projection exposure apparatus according to the fourth aspect, the aperture member has a light shielding member formed in a cross shape centered on the center of the transmission region. In the projection exposure apparatus according to the fifth aspect, the aperture member has a light shielding member that is formed radially around the center of the transmissive region. In the projection exposure apparatus according to the sixth aspect, the aperture member has a light shielding member formed in a mesh shape so as to traverse the transmission region.
In the projection exposure apparatus according to the seventh aspect, the aperture member has a light absorbing member formed so as to cross the inside of the transmission region. In the projection exposure apparatus according to claim 8, the aperture member is formed in a band shape so as to pass through the center of the transmissive region and cross the transmissive region, and is provided rotatably around the center of the transmissive region. It has the 1st and 2nd shade member.

A projection exposure apparatus according to a ninth aspect is
A light source, a mask on which a circuit pattern is formed using a shifter shading type phase shift member, a condenser lens system that irradiates the mask with the light emitted from the light source, and the light that has passed through the mask is condensed on the wafer surface. An aperture member having a projection lens system, a transmission region for forming light emitted from the light source and a light blocking member formed so as to cross the transmission region, the light transmission member being disposed between the light source and the condenser lens system. It is equipped with and. In the projection exposure apparatus according to claim 10,
The mask has a shifter light-shielding type phase shift member and a light-shielding pattern for adjusting the amount of light, which is formed on the peripheral portion of the phase shift member. In the projection exposure apparatus according to the eleventh aspect, the mask has a shifter light shielding type phase shift member and a light shielding pattern for adjusting the light amount formed in the central portion of the phase shift member. In the projection exposure apparatus according to claim 12, the mask has a semitransparent phase shift member.

According to a thirteenth aspect of the projection exposure apparatus, a light source, a Levenson type phase shift mask in which a parallel line pattern is formed, a condenser lens system for irradiating the mask with light emitted from the light source, and a mask. A projection lens system for condensing the light passing through the wafer surface onto the wafer surface, and an aperture member arranged between the light source and the condenser lens system. The aperture member is arranged in parallel with the parallel line pattern of the phase shift mask. It has a rectangular light transmission part. In the projection exposure apparatus according to the fourteenth aspect, the aperture member has a plurality of light transmitting portions arranged in parallel with the parallel line pattern of the phase shift mask. In the projection exposure apparatus according to the fifteenth aspect, the aperture member has a pin-wound light transmitting portion arranged in parallel with the parallel line pattern of the phase shift mask. In the projection exposure apparatus according to the sixteenth aspect, the aperture member has a spindle-shaped light transmitting portion arranged in parallel with the parallel line pattern of the phase shift mask. The projection exposure apparatus according to claim 17, wherein a Levenson-type phase shift mask is formed with parallel line patterns orthogonal to each other, and the aperture member is arranged in parallel with the parallel line pattern of the phase shift mask. have.

[0014]

In the present invention, the light-shielding member of the aperture member arranged between the light source and the condenser lens system shields a component of the light emitted from the light source that deteriorates the contrast and the depth of focus of the optical image. Further, by using the shifter light shielding type phase shift member for the circuit pattern of the mask, the amplitude ratio of the ± first-order light source image to the zero-order light source image can be increased. Furthermore, by arranging the rectangular light-transmitting portion of the aperture member in parallel with the parallel line pattern formed on the Levenson-type phase shift mask, the spatial coherency in the direction parallel to the parallel line pattern is lowered, and the vertical direction Spatial coherency can be increased.

[0015]

Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 is a diagram showing an optical system of a projection exposure apparatus according to a first embodiment of the present invention. A fly-eye lens 13 is arranged in front of a lamp house 11 that emits light of wavelength λ via a mirror 12. An aperture member 21 is located in front of the fly-eye lens 13, and an exposure mask 18 on which a desired circuit pattern is formed is arranged via the condenser lenses 15 and 16 and a mirror 17.
A wafer 20 is located in front of the mask 18 via a projection lens system 19. The lamp house 11, the mirror 12 and the fly-eye lens 13 form a light source, and the condenser lenses 15 and 16 and the mirror 17 form a condenser lens system.

As shown in FIGS. 2 and 3, the aperture member 21 closes a disc-shaped outer frame 22 having a circular opening 22a formed in the center thereof and the entire surface of the opening 22a of the outer frame 22. The transparent member 23 thus formed and the band-shaped light shielding member 24 formed on the surface of the transparent member 23 so as to cross the opening 22a of the outer frame 22 are provided. Outer frame 22
The opening portion 22a constitutes a transmission region D for transmitting the light from the lamp house 11. The outer frame 22 and the light shielding member 24 are made of a metal material such as aluminum, and the transparent member 23 is made of glass, for example. The light blocking member 24 can be formed by depositing a metal material on the transparent member 23.

Next, the operation of this embodiment will be described. First, the light emitted from the lamp house 11 is reflected by the mirror 1.
It reaches the fly-eye lens 13 via 2 and is divided into regions of individual lenses 13 a constituting the fly-eye lens 13. The light that has passed through each lens 13a irradiates the entire exposure region of the mask 18 via the transmission region D of the aperture member 21, the condenser lens 15, the mirror 17, and the condenser lens 16. Therefore, on the surface of the mask 18, the lights from the individual lenses 13a of the fly-eye lens 13 are overlapped with each other, and uniform illumination is performed. The light thus passing through the mask 18 reaches the wafer 20 via the projection lens system 19 and the circuit pattern is printed on the surface of the wafer 20.

Projection lens system 1 when the circuit pattern of the mask 18 has a parallel line pattern near the resolution limit.
FIG. 4 shows a light source image formed on the pupil 19a of No. 9. Pupil 1
A light source image S ₀ by 0th order light is formed at the center of 9a,
The left and right sides of this light source image S ₀ are respectively the light source images S by the primary light.
₁ and S ₂ are formed. Each of the light source images S _{0 to} S ₂ has strip-shaped light shielding portions P _{0 to} P ₂ formed by the light shielding member 24 of the aperture member 21. Here, the strip-shaped light shielding member 24 of the aperture member 21 and the mask 18
4 and the parallel line patterns of the primary light source images S ₁ and S ₂ on the pupil 19a, the light-shielding portions P ₁ and P ₂ of the primary light source images S ₁ and S ₂ are formed on the pupil 19a, as shown in FIG.
Will be located along the peripheral edge of the. Therefore, in FIG.
Light _{L 3} passing through the optical _L 0 ~L ₂ and the upper edge of each light source image _S 0 to S ₂ having an optical axis at the center point of each light source image _S 0 to S ₂ at
To L ₅ are all light blocking members 24 of the aperture member 21.
Shut off by. Therefore, the incident angle θ ₃ on the wafer 20 is
Is reduced, the depth of focus DOF is improved, and light that contributes to the background illumination is blocked to prevent deterioration of image contrast.

As described above, the aperture member 2
It is desirable that the strip-shaped light-shielding member 24 of No. 1 and the parallel line pattern of the mask 18 have a parallel relationship with each other, and thus the mask 18 has a parallel line in a direction orthogonal to the parallel line pattern described in the first embodiment. In the case of a pattern, it is preferable to use the aperture member 31 having the lateral light shielding member 41 as shown in FIG. Further, when the mask 18 includes parallel line patterns that are orthogonal to each other, the aperture member 32 including the cross-shaped light shielding member 42 centered on the central portion of the transmissive region D is used as shown in FIG. Is effective. Further, when the minimum dimensions of the parallel line patterns orthogonal to each other are different, it is preferable to use the aperture member 33 including the cross-shaped light shielding member 43 having different vertical and horizontal widths as shown in FIG. 7. When the mask 18 has a diagonal pattern in addition to the parallel line patterns orthogonal to each other, as shown in FIG. 8, the aperture member 34 having the radial light shielding member 44 centered on the central portion of the transmission region D is formed. Should be used. Also, the mask 18
Has a diagonal pattern of a specific angle such as 30 °, 60 °, etc., as shown in FIG. 9, the light shielding member 45 in which two strip-shaped members intersect at the same angle as the circuit pattern angle of the mask 18 is shown. It is preferable to use the aperture member 35 provided with.

Note that, like the aperture member 36 shown in FIG. 10, the light shielding member 46 may be formed in a thread winding shape so as to cross the transparent region D. FIG. 11 shows a light source image formed on the pupil 19a of the projection lens system 19 when the aperture member 36 is used and the circuit pattern of the mask 18 has a parallel line pattern near the resolution limit. As it can be seen from FIG. 11, the light _L 0 ~L ₂ and each light source image _S 0 to S ₂ having an optical axis at the center point of each light source image _S 0 to S ₂
All the lights L _{3 to} L ₅ passing through the upper edge portion are blocked by the light blocking member 46 of the aperture member 36, the incident angle θ ₄ on the wafer 20 is reduced, the depth of focus DOF is improved, and the contrast of the image is reduced. It is possible to prevent deterioration. By making the light shielding member 46 in the shape of a bobbin, it is possible to effectively block only the component of the light emitted from the light source that deteriorates the contrast and the depth of focus of the optical image.

Even when the light shielding member has a spool shape,
An aperture member 3 having a lateral light-shielding member 47 as shown in FIG. 12 according to the pattern of the mask 18.
7, an aperture member 38 having a cross-shaped light shielding member 48 as shown in FIG. 13 and an aperture member 39 having a cross-shaped light shielding member 49 having different vertical and horizontal widths as shown in FIG. 14 can be used. desirable.

Further, as shown in FIGS. 15 and 16, it is also possible to use an aperture member 51 in which first and second band-shaped light shielding members 64 and 74 are rotatably provided with respect to each other. The aperture member 51 has a cylindrical casing 52 and first and second rotating members 61 and 71 rotatably housed in the casing 52. A flange 53 is formed in the upper part of the casing 52 so as to project inward along the circumference thereof, and a circular opening 54 for partitioning the transparent region D of the aperture member 51 is formed in the central part of the lower surface. ing. First
The second rotating members 61 and 71 are formed so as to close the entire surfaces of the disk-shaped outer frames 62 and 72 having circular openings 62a and 72a formed in the central portions thereof and the openings 62a and 72a, respectively. Transparent members 63 and 73 and transparent members 63 and 7 so as to cross the openings 62a and 72a.
3 and the band-shaped light shielding members 64 and 74 formed on the surface of the light source 3. In addition, the lever 6 is provided on each side of the outer frames 62 and 72 of the first and second rotating members 61 and 71, respectively.
5 and 75 are attached, and the tips of these levers 65 and 75 project outside the casing 52.

Then, by moving the levers 65 and 75 along the outer peripheral portion of the casing 52, the rotating member 61
And 71 are each rotated in the casing 52. That is, the first and second light shielding members 64 and 74 are rotatable about the center of the transmissive region D, respectively,
1st and 2nd freely according to the circuit pattern of the mask 18
The angles of the light shielding members 64 and 74 can be adjusted. Therefore, by using this aperture member 51, a very practical projection exposure apparatus can be realized.

Further, like the aperture member 81 shown in FIG. 17, the light shielding member 91 may be formed in a spindle shape crossing the transmission region D. This aperture member 8
18 shows a light source image formed on the pupil 19a of the projection lens system 19 when 1 is used and the circuit pattern of the mask 18 has a relatively large parallel line pattern.
As can be seen from FIG. 18, spindle-shaped light-shielding portions P _{0 to} P ₂ and transmission portions located on both sides thereof are formed in each of the light source images S _{0 to} S ₂ . Here, the primary light source image S
The transmission parts A ₁ and A ₂ of ₁ and S ₂ correspond to the projection lens system 1
Since it is cut by the pupil 19a of No. 9, the incident angle θ ₅ on the wafer 20 becomes small. As a result, the depth of focus DOF is improved. If the aperture member 81 having the spindle-shaped light shielding member 91 is used, it is particularly effective for a circuit pattern having a size of an actual use level.

When the mask 18 has parallel line patterns orthogonal to each other, it is effective to use an aperture member 82 having a spindle-shaped and cross-shaped light shielding member 92 as shown in FIG.

Further, like the aperture member 83 shown in FIG. 20, the light shielding member 93 may be formed of a mesh having a shape that traverses the transmissive region D. A light source image formed on the pupil 19a of the projection lens system 19 when the aperture member 83 is used and the circuit pattern of the mask 18 has a relatively large parallel line pattern is shown in FIG.
Shown in 1. As can be seen from FIG. 21, each of the light source images S _{0 to} S
Each of the spindles ₂ has spindle-shaped light-shielding portions P _{0 to} P ₂ and transmission portions located on both sides thereof. Where 1
Since the transmission portions A ₁ and A ₂ of the secondary light source images S ₁ and S ₂ are cut by the pupil 19a of the projection lens system 19, the incident angle θ ₆ on the wafer 20 becomes small. As a result, the depth of focus DOF is improved. In addition, since the light blocking member 93 is formed of a mesh, some light is also introduced from the light blocking portions P _{0 to} P ₂ , whereby the effect of the modified light source method can be adjusted. If the aperture member 83 having the mesh-shaped light shielding member 93 is used, it is particularly effective for a circuit pattern having a size of an actual use level.

Although the outer shape of the light shielding member 93 is a spindle shape in FIG. 20, the shape is not limited to this, and may be, for example, a band shape or a spool shape. Further, the light blocking member 93 shown in FIG. 20 is configured such that a mesh having a finer mesh than that of the peripheral portion is formed in the central portion to enhance the light blocking effect in the central portion of each of the light source images S _{0 to} S _2. , Light blocking member 93
The central and peripheral meshes of the mesh may have a uniform roughness.

When the mask 18 has parallel line patterns orthogonal to each other, it is effective to use the aperture member 84 provided with the light shielding member 94 made of a cross-shaped mesh as shown in FIG.

Like the aperture member 85 shown in FIG. 23, the light blocking member 95 may be formed of a light absorbing film having a shape that crosses the transmissive region D. As the light absorption film, for example, a silicon nitride film is used. FIG. 24 shows a light source image formed on the pupil 19a of the projection lens system 19 when the aperture member 85 is used and the circuit pattern of the mask 18 has a relatively large parallel line pattern. As can be seen from FIG. 24, spindle-shaped light-shielding portions P _{0 to} P ₂ and transmission portions located on both sides thereof are formed in each of the light source images S _{0 to} S ₂ . Here, since the transmissive portions A ₁ and A ₂ of the primary light source images S ₁ and S ₂ are cut by the pupil 19a of the projection lens system 19, the wafer 20
The incident angle θ _{7 on} is small. As a result, the depth of focus DO
F is improved. Further, since the shielding member 95 is formed from a light absorbing layer, from the light shielding portion P ₀ to P ₂ introduces some light, thereby making it possible to adjust the effect of the modified light source method. The use of the aperture member 85 having the light shielding member 95 made of this light absorbing film is particularly effective for a circuit pattern having a size of a practical use level.

Although the light shielding member 95 has a spindle shape in FIG. 23, it is not limited to this and may have, for example, a band shape or a spool shape. In addition, the light blocking member 95 shown in FIG. 23 has a light absorbing film having a higher light absorptivity than the peripheral portion, for example, an absorbing film thicker than the peripheral portion, is formed in the central portion to form the center of each light source image S _{0 to} S ₂ . Although the light shielding effect of the portion is enhanced, the absorptance of the central portion and the peripheral portion of the light shielding member 95 may be made uniform.

When the mask 18 has parallel line patterns orthogonal to each other, it is effective to use an aperture member 86 having a light shielding member 96 made of a cross-shaped light absorbing film as shown in FIG.

As the mask 18, as shown in FIG. 26, a mask in which a circuit pattern made of a shifter light shielding type phase shift member 182 is formed on a transparent glass substrate 181, can be used. The phase shift member 182 is formed of SOG, for example. This phase shift member 182
Is formed to have a thickness that causes a half-wavelength phase difference with respect to the operating wavelength λ of the projection exposure apparatus, and the width of the phase shift member 182 and the phase shift member 182 are not provided as shown in FIG. Assuming that the line-and-space circuit pattern is formed such that the ratio with the width of only the glass substrate 181 is 1: 3, the amplitude T _{3 of the} 0th-order light source image S ₀ shown in FIG. Is 0.5, and the amplitudes T ₄ and T ₅ of the + 1st and −1st order light source images S ₁ and S ₂ are 0.
It becomes 9/2. That is, by forming the circuit pattern from the shifter light shielding type phase shift member 182, the amplitude of the 0th-order light source image S ₀ is made equal to that of the mask 8 including the light shielding portion and the light transmitting portion shown in FIG. , ±
The amplitude of the primary light source images S ₁ and S ₂ can be increased about 1.5 times. Note that in FIG. 27, the light source images S _{0 to} S
The amplitude _T 3 through T _{5 2} are represented schematically as a thickness of the disc showing the light source images _S 0 to S _2, respectively.

As shown in FIG. 27, the zero-order light source image S ₀
Shaded area _{Q 4} are light through the shaded area _{Q 3} of the +1 order light source images _{S 1}
And the light passing through the shaded portion R ₃ of the right part of the 0th-order light source image S ₀ interferes only with the light passing through the shaded portion R ₅ of the −1st-order light source image S _2. To form an image. That is, 0
The secondary light source image S ₀ is always the +1 primary light source image S ₁ and the −1 primary light source image S
_Although it interferes only with one of the _two lights, the amplitude of these ± first-order light source images S ₁ and S ₂ is about 1.5 times by using the shifter light shielding type phase shift member 182 for the mask 18. 28, the amplitude G of the optical image on the wafer 20 becomes better than the amplitude F when the mask 8 of FIG. 52 is used, as shown in FIG. As a result, the contrast of the image is improved and the transfer accuracy is improved.

The phase shift member 1 shown in FIG.
The width ratio of 82 is merely an example, and similar effects can be obtained with masks having other ratios. Further, it is not always necessary to form the entire circuit pattern of the mask with the phase shift member. For example, as in the mask 28 shown in FIG. 29, a repeating pattern or the like is formed on the transparent glass substrate 281 by the shifter light shielding type phase shift member 282, while the 0th order light and the ± 1st order light are formed in a sufficiently wide light blocking area. Since the influence of the interference is small, the pattern can be formed by the light shielding member 283 such as Cr.

When the shifter light shielding type phase shift mask is used, a mask 100 as shown in FIG. 30 may be used. The phase shifter member 1 of the shifter light shielding type is formed on the transparent substrate 101, and the phase shifter member 1 is formed.
A light shielding member 103 made of Cr or the like is formed on the peripheral portion of 02. Since the amplitude of the transmitted light when this mask 100 is used is proportional to the area of the shaded portion of the amplitude distribution shown in FIG. 30, the light amount of the transmitted light can be adjusted by changing the size of the light shielding member 103. it can.

Further, a shifter light shielding type mask 110 as shown in FIG. 31 may be used. A shifter light shielding type phase shifter member 112 is formed on a transparent substrate 111, and a light shielding member 113 is formed at the center of the phase shifter member 112. Since the amplitude of the transmitted light when this mask 110 is used is proportional to the area of the shaded portion of the amplitude distribution shown in FIG. 31, the light amount of the transmitted light can be adjusted by changing the size of the light shielding member 113. it can.

A shifter light shielding type mask 120 as shown in FIG. 32 may be used. A shifter light-shielding type phase shifter member 122 is formed on a transparent substrate 121 through a halftone light-shielding member 123, whereby a semitransparent pattern is formed. Since the amplitude of transmitted light when this mask 120 is used is proportional to the area of the shaded portion of the amplitude distribution shown in FIG. 32, the amount of transmitted light can be adjusted by changing the size of the semitransparent pattern. it can.

When the Levenson-type phase shift mask as shown in FIGS. 54 and 55 is used, FIG.
It is preferable to use the aperture member 131 shown in FIG.
The aperture member 131 has two light transmitting portions 141 arranged in the Y direction of FIG. 33 in the central portion, and the other portions block light. By using such an aperture member 131, the spatial coherency can be made different in the X direction and the Y direction. That is, the coherency in the X direction is high and the coherency in the Y direction is low.

Therefore, the orientation of the aperture member 131 is set so that the Y direction in which the two light transmitting portions 141 are arranged is parallel to the parallel line pattern of the phase shift mask.
By doing so, in the portion where the phase shift member 8e and the transparent substrate 8c of the phase shift mask of FIG. 55 are adjacent to each other, the light transmitted through the phase shift member 8e and the transparent substrate 8c and the light transmitted through only the transparent substrate 8c are Are less likely to interfere. As a result, when a positive resist is used, as shown in FIG. 34, the original pattern 10a formed by the light shielding member 8d is not generated on the wafer 10 without a deformed portion of the pattern.
Only that will be transferred accurately.

Further, the pupil 1 of the projection lens system 19 in this case is
The light source image formed on 9a is shown in FIG. Since the Levenson-type phase shift mask is used, the ± first-order light source images S ₁ and S ₂ are located closer to the center of the pupil 19a than when a light-shielding mask or a shifter light-shielding phase shift mask is used. Formed respectively. Therefore, the incident angle θ ₈ of light on the wafer 20 becomes small and the depth of focus DO
F is improved.

When the mask has a pattern of parallel lines which are orthogonal to each other, an aperture member 132 in which four four light transmitting portions 142 are arranged in each of the X direction and the Y direction as shown in FIG. 36 is used. It is effective.

Further, as shown in FIG. 37, the aperture member 133 of FIG. 33 is also used by using the aperture member 133 having the elongated rectangular light transmitting portion 143 formed in the central portion.
The same effect as 1 can be obtained. Projection lens system 1 in this case
FIG. 38 shows a light source image formed on the pupil 19 a of No. 9. Since the Levenson-type phase shift mask is used, compared with the case where a light-shielding type mask or a shifter light-shielding type phase-shifting mask is used, a ± ± position closer to the center of the pupil 19a
Primary light source images S ₁ and S ₂ are formed, respectively. Therefore, the incident angle θ ₉ of light on the wafer 20 becomes small, and the depth of focus DOF is improved.

When the mask has parallel line patterns which are orthogonal to each other, it is effective to use the aperture member 134 in which the cross-shaped light transmitting portion 144 is formed as shown in FIG.

When the Levenson type phase shift mask has a fine parallel line pattern, as shown in FIG. 40, it is preferable to use an aperture member 135 having a thread-wound light transmitting portion 145 formed in the central portion. FIG. 41 shows a light source image formed on the pupil 19a of the projection lens system 19 in this case. Since the Levenson-type phase shift mask is used, the ± first-order light source images S ₁ and S ₂ are located closer to the center of the pupil 19a than when a light-shielding mask or a shifter light-shielding phase shift mask is used. Formed respectively. Therefore, the incident angle of light on the wafer 20 is θ ₁₀
Becomes smaller and the depth of focus DOF is improved.

When the mask has parallel line patterns which are orthogonal to each other, it is effective to use the aperture member 136 in which the light transmissive portion 146 having a thread-wound shape and a cross shape is formed as shown in FIG.

On the other hand, when the Levenson-type phase shift mask has a large parallel line pattern, as shown in FIG. 43, an aperture member 137 having a spindle-shaped light transmitting portion 147 formed in the central portion is used. Good. FIG. 44 shows a light source image formed on the pupil 19a of the projection lens system 19 in this case. Since the Levenson-type phase shift mask is used, the pupil 19a is different from the case where a light-shielding mask or a shifter light-shielding phase shift mask is used.
The ± first-order light source images S ₁ and S ₂ are formed at positions close to the center of each. Therefore, the incident angle θ ₁₁ of light on the wafer 20 is reduced, and the depth of focus DOF is improved.

When the mask has parallel line patterns which are orthogonal to each other, it is effective to use an aperture member 138 having a spindle-shaped and cross-shaped light transmitting portion 148 as shown in FIG.

[0048]

As described above, the projection exposure apparatus according to the first aspect includes the light source, the condenser lens system for irradiating the mask on which the circuit pattern is formed with the light emitted from the light source, and the mask. A projection lens system for condensing the passed light on the wafer surface, and an aperture member arranged between the light source and the condenser lens system, the aperture member being a transmissive region for shaping the light emitted from the light source. Since it has a light-shielding member formed in a band shape so as to cross the inside of the transmissive region, it is possible to improve the transfer accuracy. In the projection exposure apparatus according to claim 2, since the aperture member has a light shielding member formed in a pincushion shape so as to traverse the transmission region, the contrast and the depth of focus of the optical image in the light emitted from the light source. It is possible to effectively block only the component that deteriorates. In the projection exposure apparatus according to the third aspect, since the aperture member has the light-shielding member formed in the spindle shape so as to traverse the inside of the transmission region, it is particularly effective for a pattern of a size of actual use. In addition, the transfer accuracy can be improved.

In the projection exposure apparatus according to the fourth aspect, since the aperture member has the light shielding member formed in a cross shape centered on the center of the transmission region, the mask forms parallel line patterns orthogonal to each other. When they are mixed, the transfer accuracy can be effectively improved. In the projection exposure apparatus according to claim 5, since the aperture member has a light-shielding member that is formed radially around the center of the transmissive region, the mask has an oblique pattern in addition to the parallel line patterns orthogonal to each other. When it has, the transfer accuracy can be effectively improved. In the projection exposure apparatus according to claim 6, since the aperture member has a light shielding member formed in a mesh shape so as to traverse the inside of the transmissive region, it is particularly effective for a pattern of a size of actual use level. In addition, the transfer accuracy can be improved. In the projection exposure apparatus according to claim 7, since the aperture member has the light absorbing member formed so as to traverse the inside of the transmissive area, the pattern is transferred particularly effectively to a pattern of a size of actual use. The accuracy can be improved. In the projection exposure apparatus according to claim 8, the aperture member is formed in a band shape so as to pass through the center of the transmissive region and cross the transmissive region, and is provided rotatably around the center of the transmissive region. Since the first and second light shielding members are provided, it is possible to improve the transfer accuracy without being limited to the shape of the circuit pattern of the mask.

The projection exposure apparatus according to claim 9 is:
A light source, a mask on which a circuit pattern is formed using a shifter shading type phase shift member, a condenser lens system that irradiates the mask with the light emitted from the light source, and the light that has passed through the mask is condensed on the wafer surface. An aperture member having a projection lens system, a transmission region for forming light emitted from the light source and a light blocking member formed so as to cross the transmission region, the light transmission member being disposed between the light source and the condenser lens system. Since it is provided, it is possible to increase the amplitude ratio of the ± first-order light source image to the zero-order light source image to further improve the contrast of the optical image. In the projection exposure apparatus according to claim 10, the mask has a shifter light shielding type phase shift member and a light shielding pattern for adjusting the light amount formed on the peripheral portion of the phase shift member. Can be adjusted. In the projection exposure apparatus according to claim 11, since the mask has a shifter light-shielding type phase shift member and a light-shielding pattern for adjusting the light amount formed in the central portion of the phase shift member, the exposure light amount can be easily obtained. Can be adjusted. In the projection exposure apparatus according to the twelfth aspect, since the mask has the semitransparent phase shift member, the exposure light amount can be easily adjusted.

According to a thirteenth aspect of the projection exposure apparatus, a light source, a Levenson type phase shift mask in which a parallel line pattern is formed, a condenser lens system for irradiating the mask with light emitted from the light source, and a mask. A projection lens system for condensing the light passing through the wafer surface onto the wafer surface, and an aperture member arranged between the light source and the condenser lens system. The aperture member is arranged in parallel with the parallel line pattern of the phase shift mask. Since it has a rectangular light transmitting portion, it is possible to prevent the formation of a deformation pattern due to light interference and perform highly accurate transfer. In the projection exposure apparatus according to the fourteenth aspect, since the aperture member has the plurality of light transmitting portions arranged in parallel with the parallel line pattern of the phase shift mask, the transfer accuracy can be improved. Claim 1
In the projection exposure apparatus described in No. 5, since the aperture member has the light-winding portion having a pincushion shape arranged in parallel with the parallel line pattern of the phase shift mask, the transfer accuracy of a fine pattern is particularly improved. In the projection exposure apparatus according to claim 16, since the aperture member has a spindle-shaped light transmitting portion arranged in parallel with the parallel line pattern of the phase shift mask, the transfer of a pattern of a size for actual use is achieved. Accuracy is improved. In the projection exposure apparatus according to claim 17,
Parallel line patterns that are orthogonal to each other are formed on the Levenson-type phase shift mask, and the aperture member has a cross-shaped light transmission portion that is arranged in parallel with the parallel line pattern of the phase shift mask. The transfer accuracy can be improved.

[Brief description of drawings]

FIG. 1 is a diagram showing an optical system of a projection exposure apparatus according to a first embodiment of the present invention.

FIG. 2 is a plan view showing an aperture member used in the first embodiment.

3 is a cross-sectional view taken along the line AA of FIG.

FIG. 4 is a diagram showing a relationship between a light source image formed on a pupil of a projection lens system and an incident angle on a wafer when the aperture member of FIG. 2 is used.

FIG. 5 is a plan view showing an aperture member used in a second embodiment.

FIG. 6 is a plan view showing an aperture member used in a third embodiment.

FIG. 7 is a plan view showing an aperture member used in a fourth embodiment.

FIG. 8 is a plan view showing an aperture member used in a fifth embodiment.

FIG. 9 is a plan view showing an aperture member used in a sixth embodiment.

FIG. 10 is a plan view showing an aperture member used in a seventh embodiment.

11 is a diagram showing the relationship between the light source image formed on the pupil of the projection lens system and the incident angle to the wafer when the aperture member of FIG. 10 is used.

FIG. 12 is a plan view showing an aperture member used in an eighth embodiment.

FIG. 13 is a cross-sectional view showing an aperture member used in a ninth embodiment.

FIG. 14 is a sectional view showing an aperture member used in a tenth embodiment.

FIG. 15 is a plan view showing an aperture member used in an eleventh embodiment.

16 is a sectional view taken along the line BB of FIG.

FIG. 17 is a plan view showing an aperture member used in a twelfth embodiment.

18 is a diagram showing the relationship between the light source image formed on the pupil of the projection lens system and the angle of incidence on the wafer when the aperture member of FIG. 17 is used.

FIG. 19 is a plan view showing an aperture member used in a thirteenth embodiment.

FIG. 20 is a plan view showing an aperture member used in a fourteenth embodiment.

21 is a diagram showing the relationship between the light source image formed on the pupil of the projection lens system and the angle of incidence on the wafer when the aperture member of FIG. 20 is used.

FIG. 22 is a plan view showing an aperture member used in a fifteenth embodiment.

FIG. 23 is a plan view showing an aperture member used in a 16th embodiment.

24 is a diagram showing the relationship between the light source image formed on the pupil of the projection lens system and the incident angle on the wafer when the aperture member of FIG. 23 is used.

FIG. 25 is a plan view showing an aperture member used in a seventeenth embodiment.

FIG. 26 is a view showing a mask used in the eighteenth embodiment.

27 is a diagram showing a light source image formed on the pupil of the projection lens system when the mask of FIG. 26 is used.

28 is a diagram showing the amplitude of an optical image on a wafer when the mask of FIG. 26 is used.

FIG. 29 is a sectional view showing a mask used in a nineteenth embodiment.

FIG. 30 is a diagram showing a cross section of a mask used in a twentieth example and an amplitude of an optical image on a wafer.

FIG. 31 is a diagram showing a cross section of a mask used in a twenty-first embodiment and the amplitude of an optical image on a wafer.

FIG. 32 is a diagram showing a cross section of a mask used in a 22nd example and the amplitude of an optical image on a wafer.

FIG. 33 is a plan view showing an aperture member used in the 23rd Example.

34 is a plan view showing a positive resist pattern on a wafer when the aperture member shown in FIG. 33 is used.

35 is a diagram showing the relationship between the light source image formed on the pupil of the projection lens system and the angle of incidence on the wafer when the aperture member of FIG. 33 is used.

FIG. 36 is a plan view showing an aperture member used in the 24th embodiment.

FIG. 37 is a plan view showing an aperture member used in the 25th embodiment.

38 is a diagram showing the relationship between the light source image formed on the pupil of the projection lens system and the angle of incidence on the wafer when the aperture member of FIG. 37 is used.

FIG. 39 is a plan view showing an aperture member used in the 26th embodiment.

FIG. 40 is a plan view showing an aperture member used in the 27th embodiment.

41 is a diagram showing the relationship between the light source image formed on the pupil of the projection lens system and the angle of incidence on the wafer when the aperture member of FIG. 40 is used.

FIG. 42 is a plan view showing an aperture member used in the 28th Example.

FIG. 43 is a plan view showing an aperture member used in the 29th embodiment.

44 is a diagram showing the relationship between the light source image formed on the pupil of the projection lens system and the angle of incidence on the wafer when the aperture member of FIG. 43 is used.

FIG. 45 is a plan view showing an aperture member used in the 30th embodiment.

FIG. 46 is a diagram showing an optical system of a conventional projection exposure apparatus.

47 is a plan view showing an aperture member used in the device of FIG. 46. FIG.

48 is a cross-sectional view taken along the line CC of FIG. 47.

49 is a relationship between the light source image formed on the pupil of the projection lens system and the incident angle to the wafer when the aperture member of FIG. 47 is used and the circuit pattern of the mask has a parallel line pattern near the resolution limit. FIG.

FIG. 50 shows the relationship between the light source image formed on the pupil of the projection lens system and the angle of incidence on the wafer when another conventional aperture member is used and the circuit pattern of the mask has a parallel line pattern near the resolution limit. It is a figure which shows a relationship.

FIG. 51 is a diagram showing a light source image formed on the pupil of the projection lens system when another conventional aperture member is used.

FIG. 52 is a diagram showing a shifter light shielding type phase shift mask.

53 is a diagram showing the amplitude of the optical image on the wafer when the mask of FIG. 52 is used.

FIG. 54 is a cross-sectional view showing a Levenson-type phase shift mask.

55 is a plan view showing the mask of FIG. 54. FIG.

56 is a plan view showing a positive resist pattern on a wafer when the mask of FIG. 54 is used.

[Explanation of symbols]

11 Lamphouse 12, 17 Mirror 13 Fly-eye lens 15, 16 Condensing lens 18, 28, 100, 110, 120 Mask 19 Projection lens system 20 Wafer 21, 31-39, 51, 81-86, 131-138
Aperture member 24, 41-49, 91-96, 103, 113, 12
3 light-shielding member 64 1st light-shielding member 74 2nd light-shielding member 102, 112, 122, 182, 282, phase shift member 141-148 light transmission part

Claims (17)

[Claims] 1. A light source, a condenser lens system for irradiating light emitted from the light source onto a mask having a circuit pattern formed thereon, and a projection lens system for condensing light passing through the mask onto a wafer surface. An aperture member arranged between the light source and the condenser lens system, wherein the aperture member is formed in a transmissive region for shaping the light emitted from the light source and in a band shape so as to cross the transmissive region. And a light-shielding member that is formed. 2. A light source, a condenser lens system for irradiating light emitted from the light source onto a mask on which a circuit pattern is formed, and a projection lens system for condensing light passing through the mask onto a wafer surface. An aperture member disposed between the light source and the condenser lens system, wherein the aperture member has a transmissive region for shaping the light emitted from the light source and a pincushion shape so as to cross the transmissive region. A projection exposure apparatus having a formed light shielding member. 3. A light source, a condenser lens system for irradiating light emitted from the light source onto a mask on which a circuit pattern is formed, and a projection lens system for condensing light passing through the mask onto a wafer surface. An aperture member disposed between the light source and the condenser lens system, wherein the aperture member has a transmissive region for shaping the light emitted from the light source and a spindle shape so as to cross the transmissive region. A projection exposure apparatus having a formed light shielding member. 4. A light source, a condenser lens system for irradiating light emitted from the light source onto a mask on which a circuit pattern is formed, and a projection lens system for condensing light passing through the mask onto a wafer surface. An aperture member arranged between the light source and the condenser lens system, wherein the aperture member is a transmissive region for shaping the light emitted from the light source and a cross centered on a central portion of the transmissive region. A projection exposure apparatus having a light-shielding member formed in a shape. 5. A light source, a condenser lens system for irradiating light emitted from the light source onto a mask on which a circuit pattern is formed, and a projection lens system for condensing light passing through the mask onto a wafer surface. An aperture member arranged between the light source and the condenser lens system is provided, and the aperture member is radially centered on a transmission region for shaping light emitted from the light source and a central portion of the transmission region. A projection exposure apparatus having a formed light shielding member. 6. A light source, a condenser lens system for irradiating light emitted from the light source onto a mask on which a circuit pattern is formed, and a projection lens system for condensing light passing through the mask onto a wafer surface. An aperture member arranged between the light source and the condenser lens system, wherein the aperture member has a mesh shape so as to traverse the transmission region and the transmission region for shaping the light emitted from the light source. A projection exposure apparatus having a formed light shielding member. 7. A light source, a condenser lens system for irradiating light emitted from the light source onto a mask having a circuit pattern formed thereon, and a projection lens system for condensing light passing through the mask onto a wafer surface. An aperture member disposed between the light source and the condenser lens system is provided, and the aperture member is formed so as to cross the transmission region for shaping the light emitted from the light source and the transmission region. A projection exposure apparatus having a light absorbing member. 8. A light source, a condenser lens system for irradiating light emitted from the light source onto a mask on which a circuit pattern is formed, and a projection lens system for condensing light passing through the mask onto a wafer surface. An aperture member disposed between the light source and the condenser lens system, wherein the aperture member transmits through a transmission region for shaping light emitted from the light source and a central portion of the transmission region. A projection exposure apparatus, comprising: a first and a second light shielding member which are formed in a band shape so as to cross the area and are rotatably provided around a central portion of the transmission area. 9. A light source, a mask on which a circuit pattern is formed using a shifter light shielding type phase shift member, a condenser lens system for irradiating the light emitted from the light source onto the mask, and a mask which passes through the mask. A projection lens system for condensing the generated light on the surface of the wafer, a transmissive region which is arranged between the light source and the condensing lens system and which shapes the light emitted from the light source, and traverses the transmissive region. And an aperture member having a light-shielding member formed as described above. 10. A mask having a light source, a shifter light shielding type phase shift member, and a light amount adjusting light shielding pattern formed on a peripheral portion of the phase shift member, and light emitted from the light source on the mask. A condenser lens system for irradiating, a projection lens system for condensing the light passing through the mask on the wafer surface, and a light source emitted from the light source and arranged between the light source and the condenser lens system. A projection exposure apparatus comprising: an aperture member having a transmissive region for effecting the above and a light shielding member formed so as to cross the transmissive region. 11. A mask having a light source, a shifter light shielding type phase shift member, and a light amount adjusting light shielding pattern formed in a central portion of the phase shift member, and light emitted from the light source on the mask. A condenser lens system for irradiating, a projection lens system for condensing the light passing through the mask on the wafer surface, and a light source emitted from the light source and arranged between the light source and the condenser lens system. A projection exposure apparatus comprising: an aperture member having a transmissive region for effecting the above and a light shielding member formed so as to cross the transmissive region. 12. A light source, a mask on which a circuit pattern is formed using a semitransparent phase shift member, a condenser lens system for irradiating the mask with light emitted from the light source, and a mask passing through the mask. A projection lens system for condensing light on the surface of the wafer, a transmissive region arranged between the light source and the condensing lens system for shaping the light emitted from the light source, and traversing the transmissive region. A projection exposure apparatus, comprising: an aperture member having a light blocking member formed on the substrate. 13. A light source, a Levenson-type phase shift mask having a parallel line pattern formed thereon, a condenser lens system for irradiating the mask with light emitted from the light source, and a wafer for transmitting light passing through the mask. A projection lens system for condensing on a surface, and an aperture member arranged between the light source and the condenser lens system, the aperture member being a rectangle arranged in parallel with a parallel line pattern of the phase shift mask. A projection exposure apparatus having a light-transmitting portion having a shape. 14. A light source, a Levenson-type phase shift mask having a parallel line pattern formed thereon, a condenser lens system for irradiating the mask with light emitted from the light source, and a wafer for transmitting light passing through the mask. A projection lens system for condensing on a surface, and an aperture member arranged between the light source and the condenser lens system, wherein the aperture members are arranged in parallel with a parallel line pattern of the phase shift mask. A projection exposure apparatus comprising: 15. A light source, a Levenson-type phase shift mask having a parallel line pattern formed thereon, a condenser lens system for irradiating the mask with light emitted from the light source, and a wafer for transmitting light passing through the mask. A projection lens system for condensing on a surface, and an aperture member arranged between the light source and the condenser lens system, wherein the aperture member is arranged in parallel with the parallel line pattern of the phase shift mask. A projection exposure apparatus having a light-transmitting portion having a shape. 16. A light source, a Levenson-type phase shift mask having a parallel line pattern formed thereon, a condenser lens system for irradiating the mask with light emitted from the light source, and a wafer for transmitting light passing through the mask. A projection lens system for condensing on a surface, and an aperture member arranged between the light source and the condenser lens system, wherein the aperture member is a spindle shape arranged in parallel with a parallel line pattern of the phase shift mask. A projection exposure apparatus, which has a light-transmitting portion. 17. A light source, a Levenson-type phase shift mask in which parallel line patterns orthogonal to each other are formed, a condenser lens system for irradiating the mask with light emitted from the light source, and a light passing through the mask. A projection lens system for condensing light on the wafer surface, and an aperture member arranged between the light source and the condenser lens system, wherein the aperture member is arranged in parallel with a parallel line pattern of the phase shift mask. Projection exposure apparatus having a cross-shaped light transmitting portion formed into a cross.