JP2002023057A - Projection optical system and aligner equipped therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To excellently restrain influence exerted on image-formation performance such as deformation by the gravity of a lens component while securing large-size projection field in one direction in a cata-dioptric type projection optical system. SOLUTION: This cata-dioptric type projection optical system is equipped with at least one concave reflection mirror (CM) and plural lens components (Li), and projects the image of a slit-shaped pattern extended in a specified direction on a first surface (M) to a second surface (P). Then, it is provided with at least one lens component (L32 to L34) arranged at a position comparatively near to the first surface (M) or the second surface (P), and supported on the outside of an effective area where image-formation luminous flux contributing to the formation of the image of the slit-shaped pattern passes and on the inside of a circular area circumscribing the effective area.

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 and an exposure apparatus provided with the optical system, and more particularly to a scanning type for projecting and exposing a mask pattern on a photosensitive substrate while moving the mask and the photosensitive substrate. The present invention relates to a catadioptric projection optical system suitable for an exposure apparatus.

[0002]

2. Description of the Related Art In recent years, liquid crystal display panels have been frequently used as display elements for word processors, personal computers, televisions, and the like. A liquid crystal display panel is manufactured by patterning a transparent thin-film electrode on a plate into a desired shape by a photolithography technique. As an apparatus for the photolithography process, a projection exposure apparatus that projects and exposes an original pattern formed on a mask to a photoresist layer on a plate via a projection optical system is used.

In recent years, there has been an increasing demand for a large-sized liquid crystal display panel, and with this demand, it has been desired to enlarge the exposure area in this type of projection exposure apparatus.
Therefore, in order to cope with the enlargement of the photosensitive substrate to be exposed, the exposure region of the photosensitive substrate is divided into a plurality of unit regions, and scanning exposure corresponding to each unit region is repeated, and finally a desired pattern is formed. A screen combining method for combining is used. When performing this screen synthesis, in order to prevent the occurrence of a break in the pattern at the boundary position of each exposure area, exposure is performed by superimposing a small amount of the boundary of each exposure area.

[0004]

However, in the screen synthesizing method, if the overlapping accuracy between the adjacent exposure regions is not sufficiently high, a step occurs at the joint portion of the pattern, and the characteristics of the device are impaired. May be
In other words, differences in image quality of the optical system and subtle differences in illumination conditions in the exposure area affect the seams of the pattern,
Unevenness occurs in the generation of device patterns.

In order to form a large-area device pattern by one scanning exposure, it is conceivable to enlarge the projection optical system. However, in a projection optical system that has been enlarged to secure a large exposure area (projection field of view), the effective diameter of the lens disposed particularly on the enlargement side becomes large, and the imaging performance such as deformation due to the weight of the lens is reduced. Can no longer be ignored. In a catadioptric projection optical system including a concave reflecting mirror and a plurality of lenses, the number of lenses can be reduced as compared with a refraction projection optical system, which is advantageous in increasing the size of the optical system. It is.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has a good effect on image forming performance such as deformation due to the weight of a lens component while securing a projection field of a large dimension along one direction. It is an object of the present invention to provide a catadioptric projection optical system which can be suppressed to a minimum. It is another object of the present invention to provide an exposure apparatus that can form a large-area device pattern by one scanning exposure using a catadioptric projection optical system having a projection field of a large dimension along one direction. And

[0007]

According to a first aspect of the present invention, there is provided at least one concave reflecting mirror and a plurality of lens components. In a catadioptric projection optical system for projecting an image of an extended slit-like pattern onto a second surface,
Outside the effective region through which the imaging light flux contributing to the formation of the image of the slit-shaped pattern is disposed and relatively inside the circular region circumscribing the effective region. The lens component L1 has at least one supported lens component L1, the maximum effective radius of the lens component L1 (the radius of the circular region) is H, and the lens component L1
A projection optical system characterized by satisfying a condition of X <0.75H, where X is a distance between a support point closest to the optical axis and the optical axis.

According to a preferred aspect of the first invention, the lens component L1 is disposed on the enlargement side of the projection optical system with its optical axis extending along the direction of gravity. Further, it is preferable that the lens component L1 has a cutout shape excluding the effective area and a support area outside the effective area, and is supported by a holding member that is in contact with the support area. In this case, it is preferable that the contact portion of the support region of the lens component L1 is formed in a planar shape.

According to a preferred embodiment of the first invention,
The total projected area of the lens component L1 on a plane perpendicular to the optical axis of the effective area and the support area is S1, and the projected area of the cutout area of the lens component L1 on a plane perpendicular to the optical axis is S1. When S2, the condition of S1 <S2 is satisfied. Preferably, the second surface and the first surface are telecentric.

According to a second aspect of the present invention, there is provided a projection optical system according to the first aspect of the present invention, and an illumination optical system for illuminating a mask set on the first surface, wherein the mask is provided to the projection optical system. And an exposure apparatus for projecting and exposing a pattern formed on the mask onto the photosensitive substrate while relatively moving a photosensitive substrate set on the second surface. In this case, it is preferable that the illumination optical system illuminates the mask with light having a wavelength smaller than 450 nm.

According to another aspect of the present invention, an image of a slit-like pattern extending along a predetermined direction on a first surface, comprising at least one concave reflecting mirror and a plurality of lens components, is provided. In a catadioptric projection optical system that projects onto two surfaces, at least one lens component having a predetermined portion cut out leaving an effective area through which an imaging light beam contributing to the formation of the image of the slit pattern passes. A projection optical system is provided.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In general, in an exposure apparatus for forming a device pattern by batch exposure, an image of a pattern formed in a square illumination area on a mask is projected on a square exposure area on a photosensitive substrate. It is formed. Therefore, the shape of the effective area in which the image forming light beam contributing to the formation of the pattern image passes through each lens is almost circular regardless of the position of each lens. As a result, in a one-time exposure type exposure apparatus, when the size of the projection optical system is increased, the effective area of each lens is enlarged in a circular shape, and each lens requires a two-dimensionally large dimension.

On the other hand, in the case of a scanning type exposure apparatus which forms a device pattern by one scanning exposure without synthesizing a screen, an image of a pattern formed in an elongated rectangular (or slit) illumination area on a mask. Are formed in an elongated rectangular exposure area on the photosensitive substrate. Therefore, the effective area where the imaging light beam contributing to the formation of the pattern image passes through the lens disposed at a position relatively close to the mask or the photosensitive substrate has an elongated rectangular shape.

As a result, in the scanning type exposure apparatus, even if the projection optical system is enlarged, the effective area of the lens arranged relatively close to the mask or the photosensitive substrate is enlarged into an elongated rectangular shape, and the mask or the exposure area is enlarged. A lens disposed relatively close to the photosensitive substrate requires a large dimension in a predetermined direction, but does not require a large dimension along a direction orthogonal to the predetermined direction. In the present invention, a region through which an image forming light beam passes is defined as an effective region, and a radius of a circular region circumscribing the effective region is defined as a maximum effective radius.

In this case, in a 1 × projection optical system for forming a 1 × image of a pattern, a lens disposed near the mask and a lens disposed near the photosensitive substrate have substantially the same maximum effective radius as each other. Have. However, for example, in an enlarged projection optical system that forms an enlarged image of a pattern, a lens arranged near the photosensitive substrate has a larger maximum effective radius than a lens arranged near the mask. That is, the lens disposed on the enlargement side of the projection optical system requires a larger maximum effective radius than the lens disposed on the reduction side of the projection optical system.

Based on the above findings, the inventor of the present invention
In order to favorably suppress the influence on the imaging performance such as deformation due to the weight of the lens disposed at a position relatively close to the mask or the photosensitive substrate, a circular area outside the effective area and circumscribing the effective area is required. It has been found that it is advantageous to support inside. That is, in the present invention, the lens component L1, which is disposed at a position relatively close to the mask or the photosensitive substrate and is easily enlarged, satisfies the following conditional expression (1).

X <0.75H (1) where H is the maximum effective radius of the lens component L1.
X is a distance between the optical axis and the support point closest to the optical axis of the lens component L1. When X is out of the range defined by the conditional expression (1), the influence of the own weight of the lens component L1 cannot be ignored.

In the present invention, it is preferable that the lens component L1 is disposed on the enlargement side of the projection optical system with its optical axis extending along the direction of gravity. Lens component L
By supporting the first optical axis in a posture extending along the direction of gravity, the deformation property of the lens component L1 due to its own weight becomes symmetrical with respect to the optical axis, so that the influence on the imaging performance of the projection optical system can be reduced. . Further, the lens component L1 disposed on the enlargement side of the projection optical system is the lens which is most easily enlarged as described above, and the effect of the present invention can be exhibited most effectively for the lens which is most easily enlarged. it can.

Further, in the present invention, it is preferable that the lens component L1 has a cutout shape excluding the effective area and the support area outside the effective area, and is supported by a holding member abutting on the support area. By cutting off other unnecessary areas while leaving an effective area essential for transmitting the imaging light flux and a support area essential for supporting the lens, the weight of the lens component L1 can be significantly reduced. This is advantageous in terms of supporting the lens and deformation due to its own weight. Further, the lens component L1 is supported by a holding member that abuts on the support region, and the contact portion of the support region is formed in a planar shape, so that the lens component L1 is stably supported with a simple configuration. It becomes possible.

Further, in the present invention, it is preferable to satisfy the following conditional expression (2). S1 <S2 (2) Here, S1 is the total projected area of the effective area and the support area of the lens component L1 onto a plane perpendicular to the optical axis. S2 is the projected area of the cutout area of the lens component L1 onto a plane perpendicular to the optical axis. If S2 is smaller than the range defined by the conditional expression (2), the cut-out area becomes too small, and the effect of reducing the weight of the lens component L1 cannot be sufficiently expected, which is not preferable.

In the present invention, the projection optical system is preferably telecentric on the mask side and the photosensitive substrate side. With this configuration, even if the mask or the photosensitive substrate is moved in the focusing direction for adjusting the focus of the projection optical system, the occurrence of distortion can be substantially avoided. Further, in the present invention, it is preferable to illuminate the mask with ultraviolet light having a wavelength smaller than 450 nm. Exposure light having a wavelength larger than this wavelength cannot achieve a sufficient resolution, and is not suitable for manufacturing a high-definition micro device such as a liquid crystal display device.

In the above description, the present invention is applied to a lens component which is arranged near a mask or a photosensitive substrate and is easily enlarged. However, irrespective of the position and orientation of the lens component, by cutting out a predetermined portion while leaving an effective area through which the imaging light beam passes, an effect of reducing the weight of the lens component can be expected from the viewpoint of, for example, imaging performance. .

As described above, in the catadioptric projection optical system of the present invention, a large projection field of view is ensured in one direction, and the influence on the imaging performance such as deformation due to the weight of the lens component is maintained. It can be suppressed well. Further, in the exposure apparatus of the present invention, a large-area device pattern can be formed by one scanning exposure using a catadioptric projection optical system having a projection field of a large dimension in one direction.

An embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a view schematically showing a configuration of an exposure apparatus including a projection optical system according to an embodiment of the present invention. FIG. 2 is a diagram schematically showing a configuration of the projection optical system of FIG. In FIG. 1, the Z axis is along the normal direction of a plate (glass substrate) P which is a photosensitive substrate, the Y axis is in the plate plane in a direction parallel to the plane of FIG. 1, and the FIG. The X axis is set in a direction perpendicular to the paper surface.

The exposure apparatus shown in FIG. 1 includes a light source 1 composed of, for example, a high-pressure mercury lamp. The light source 1 is positioned at a first focal position of an elliptical mirror 2 having a reflection surface formed of a spheroid. Therefore, the illumination light flux emitted from the light source 1 forms a light source image at the second focal position of the elliptical mirror 2 via the mirror 3. The light beam from the light source image formed at the second focal position of the elliptical mirror 2 is converted into a substantially parallel light beam by the collimator lens 4 and then passed to a wavelength selection filter 5 for selectively transmitting a light beam in a desired wavelength range. Incident. In the case of the present embodiment, in the wavelength selection filter 5, g
Line (λ = 436 nm) light, h-line (λ = 405 nm) light, and i-line (λ = 365 nm) light are selectively transmitted.

The light of the exposure wavelength selected via the wavelength selection filter 5 enters a fly-eye lens 6 as an optical integrator. Fly eye lens 6
Is constituted by arranging a number of lens elements having a positive refractive power vertically and horizontally and densely so that their optical axes are parallel to a reference optical axis AX. Each lens element constituting the fly-eye lens 6 has a rectangular cross-section similar to the shape of the illumination field to be formed on the mask (and the shape of the exposure area to be formed on the plate). In addition, the surface on the incident side of each lens element constituting the fly-eye lens 6 is formed in a spherical shape with the convex surface facing the incident side, and the surface on the emitting side is formed in a spherical shape with the convex surface facing the emitting side. .

Therefore, the light beam incident on the fly-eye lens 6 is split into wavefronts by a number of lens elements.
One light source image is formed on the rear focal plane of each lens element. In other words, on the rear focal plane of the fly-eye lens 6, a substantial surface light source, that is, a secondary light source composed of many light source images is formed. The luminous flux from the secondary light source formed on the rear focal plane of the fly-eye lens 6 enters the aperture stop 7 disposed near the secondary light source. The aperture stop 7 is arranged at a position optically substantially conjugate with an entrance pupil plane of the projection optical system PL, which will be described later, and has a variable aperture for defining a range contributing to illumination of the secondary light source. The aperture stop 7 changes the aperture diameter of the variable aperture to determine the illumination condition (the ratio of the aperture of the secondary light source image on the pupil plane to the aperture diameter of the pupil plane of the projection optical system). Is set to the desired value.

The light from the secondary light source through the aperture stop 7 is
After receiving the light-condensing action of the condenser optical system 8, the mask M on which a predetermined pattern is formed is uniformly illuminated in a superimposed manner.
In this manner, on the mask M, a rectangular illumination area that is elongated in the X direction and similar to the cross-sectional shape of each lens element of the fly-eye lens 6 is formed. Note that a mask blind and a blind imaging optical system as a field stop for defining the shape of the illumination area formed on the mask M may be arranged in the optical path between the condenser optical system 8 and the mask M. .

The mask M is held on a mask stage MS in parallel with an XZ plane (ie, a vertical plane) via a mask holder (not shown). Mask stage M
S can be moved two-dimensionally along the mask plane (ie, XZ plane) by the action of a drive system (not shown), and its position coordinates are measured and controlled by a mask interferometer (not shown). It is configured to:

The light flux transmitted through the pattern of the mask M forms a rectangular mask pattern image extending in the X direction on the plate P, which is a photosensitive substrate, via the catadioptric projection optical system PL. . The plate P is held on a plate stage PS in parallel with an XY plane (that is, a horizontal plane) via a plate holder (not shown). The plate stage PS can be moved two-dimensionally along the plate surface (that is, the XY plane) by the action of a drive system (not shown), and its position coordinates are measured by a plate interferometer (not shown) and position control is performed. It is configured to be.

Thus, the mask M is moved along the Z direction with respect to the projection optical system PL, and the plate P is moved to the Y direction.
By performing scanning exposure while moving along the direction, the pattern of the mask M is projected and exposed on the exposure region of the plate P. That is, in the exposure area of the plate P,
The size of the rectangular mask pattern image formed in the stationary state along the X direction and the plate P in the scanning exposure
Is formed in a rectangular pattern defined by the size corresponding to the moving distance along the Y direction.

Referring now to FIG. 2, in the catadioptric projection optical system PL according to the present embodiment, light from the mask M is transmitted through the first lens group G1 to the beam splitter B.
It is incident on S. The light reflected in the + Z direction by the beam splitter BS passes through the second lens group G2 to the concave reflecting mirror C
M is incident. The light reflected by the concave reflecting mirror CM is the second light.
The light again enters the beam splitter BS via the lens group G2. The light transmitted through the beam splitter BS reaches the plate P via the third lens group G3.

The first lens group G1 is arranged in order from the mask side.
It is composed of a biconvex lens L11, a negative meniscus lens L12 having a convex surface facing the mask side, a biconvex lens L13, and a biconvex lens L14. Also, the second lens group G2
Is composed of, in order from the beam splitter side, a plano-concave lens L21 having a flat surface facing the beam splitter side, and a negative meniscus lens L22 having a convex surface facing the beam splitter side. Further, the third lens group G3 includes, in order from the beam splitter side, a positive meniscus lens L31 having a concave surface facing the beam splitter side, a biconvex lens L32, and a negative meniscus lens L having a concave surface facing the beam splitter side.
33 and a biconvex lens L34.

In order to avoid a light quantity loss at the beam splitter BS, a polarizing beam splitter PBS is used as the beam splitter, and the beam splitter PBS and the concave reflecting mirror CM are used in the optical path and between the polarizing beam splitter PBS. It is preferable to insert a 波長 wavelength plate in the optical path between the plate P and each of them. In this case, the linearly polarized light from the mask M enters the polarization beam splitter PBS in the S-polarized state via the first lens group G1. The linearly polarized light in the S-polarized state reflected by the polarizing beam splitter PBS passes through the quarter-wave plate twice and reenters the polarizing beam splitter PBS in the P-polarized state. The linearly polarized light in the P polarization state transmitted through the polarization beam splitter PBS reaches the plate P in a circularly polarized state by transmitting once through the quarter-wave plate.

As shown in FIG. 2, the projection optical system PL of this embodiment is configured as an enlargement optical system, and forms an enlarged pattern image of the mask M on the plate P. Therefore, the lenses L32 to L34 arranged at positions relatively closer to the plate P on the enlargement side (plate side) are lenses L11 to L13 arranged at positions relatively closer to the mask M on the reduction side (mask side). It has a larger effective diameter. Therefore, in the present embodiment, the lenses L32 to L32 arranged at positions relatively close to the plate P on the enlargement side
It is preferable to apply the present invention to 34. Hereinafter, the present embodiment will be described focusing on application of the present invention to the lens L32.

FIG. 3 is a view for explaining an effective area, a support area, and a cut-out cutout area of the lens according to the application of the present invention. As shown by the broken line in FIG.
In the lens L32, the effective area R through which the imaging light flux passes
Reference numeral 1 denotes an elongated rectangular shape centered on the optical axis AX1 of the lens L32 (coincident with the optical axis AX of the projection optical system PL). A support region R2 is provided outside the effective region R1,
Excision region R3 leaving effective region R1 and support region R2
(Indicated by hatching in the figure) are notched.

Here, the radius of a circular area (not shown) circumscribing the effective area R1 is the maximum effective radius H of the lens L32. In the present embodiment, as described later, since the lens L32 is supported by surface contact over the entire support region R2, the distance between the support point closest to the optical axis AX1 of the lens L32 and the optical axis AX1. The distance is X. Further, the total projected area of the effective region R1 and the support region R2 on a plane perpendicular to the optical axis AX1 is S1, and the projected area of the resection region R3 on a plane perpendicular to the optical axis AX1 is S2.

FIG. 4 is a perspective view for explaining a lens supporting form according to the application of the present invention. FIG. 5 is a view of the support member viewed from the plate side along the optical axis of the lens of FIG. As shown in FIGS. 4 and 5, the support member 41 of the lens L32 has a rectangular parallel plate shape as a whole, and has a rectangular opening 41a at the center thereof. The surface of the lens L32 on the support member side of the support region R2 is processed into a flat shape, and the lens L32 is supported by the support member 41 by surface contact over the entire support region R2.

The lens L32 is positioned at a predetermined position on the support member 41 by fastening means comprising a combination of a screw 42 and a stopper 43 formed of a suitable material such as metal or ceramics. At this time, it goes without saying that the effective region R1 of the lens L32 is positioned within the range of the opening 41a of the support member 41. The other lenses L33 and L34 are supported similarly to the lens L32.

As described above, in the present embodiment, the lenses L33 to L35 arranged relatively close to the plate P
Are supported just outside its effective area. Therefore, even if the size of the projection optical system PL is increased so that a projection field of a large dimension can be ensured in one direction, the influence on the imaging performance such as deformation due to the weight of the lenses L33 to L35, which tends to increase in size, is not affected. It can be suppressed well. As a result, in the exposure apparatus of the present embodiment, a large-area device pattern can be formed by one scanning exposure.

In FIG. 2, the lenses L11 to L13 disposed relatively close to the mask M on the reduction side are also notched. This embodiment will be described focusing on the lens L11. Unlike the lens L32 described above, the top and bottom of the circular lens in the direction of gravity (Z direction) are notched. For this reason, the central portion of the lens L11 is more easily bent than the circular lens. FIG. 6 is a plan view for explaining a supporting form of the lens 11 for coping with the deflection.

The support member 51 of the lens L11 has the shape of a rectangular parallel plate as a whole, and has a rectangular opening 51a at the center. The support member 51 on the lower surface side of the lens L11 is provided with three support protrusions 52 serving as a height reference. One of the three support protrusions 52 is provided at a central position where the lens L11 bends most. The support member 51 on one side surface of the lens L11 is provided with one support protrusion 52 serving as a lateral reference. A pressing spring 53 is provided at a symmetric position of the support projection 52 via the lens L11, and the pressing spring 53 is always provided.
Are arranged at desired positions. Instead of providing the three support protrusions 52 serving as a height reference, the lens L11 may be mounted on a plane which is in contact with the lower surface of the lens L11.

In this embodiment, each optical member and each stage in the embodiment shown in FIG. 1 are electrically, mechanically or optically connected so as to achieve the above-described functions. An exposure apparatus can be assembled. Next, in the exposure apparatus shown in FIG. 1, a liquid crystal display element as a micro device can be obtained by forming a predetermined pattern (circuit pattern, electrode pattern, etc.) on a plate (glass substrate). Hereinafter, an example of the technique at this time will be described with reference to the flowchart of FIG.

Referring to FIG. 7, in a pattern forming step 401, a mask (reticle) is formed using the exposure apparatus of the present embodiment.
A so-called photolithography step of transferring and exposing the pattern to a photosensitive substrate (eg, a glass substrate coated with a resist) is performed. By this photolithography process, a predetermined pattern including a large number of electrodes and the like is formed on the photosensitive substrate. Thereafter, the exposed substrate is subjected to various steps such as a developing step, an etching step, and a reticle peeling step, whereby a predetermined pattern is formed on the substrate, and the process proceeds to the next color filter forming step 402.

Next, in the color filter forming step 402, three colors corresponding to R (Red), G (Green) and B (Blue) are used.
Many sets of dots are arranged in a matrix,
Alternatively, a color filter in which a plurality of sets of three stripe filters of R, G, and B are arranged in the horizontal scanning line direction is formed. Then, after the color filter forming step 402, a cell assembling step 403 is performed.

In the cell assembling step 403, the substrate having the predetermined pattern obtained in the pattern forming step 401,
Then, a liquid crystal panel (liquid crystal cell) is assembled using the color filters and the like obtained in the color filter forming step 402. In the cell assembling step 403, for example, a liquid crystal is injected between the substrate having the predetermined pattern obtained in the pattern forming step 401 and the color filter obtained in the color filter forming step 402, and a liquid crystal panel (liquid crystal cell) is formed. ) To manufacture.

Thereafter, in a module assembling step 404, components such as an electric circuit and a backlight for performing a display operation of the assembled liquid crystal panel (liquid crystal cell) are attached to complete a liquid crystal display element. According to the above-described method for manufacturing a liquid crystal display device, a liquid crystal display device having an extremely fine circuit pattern can be obtained with high throughput.

A semiconductor device as a microdevice can be obtained by forming a predetermined circuit pattern on a wafer or the like as a photosensitive substrate using the exposure apparatus according to the embodiment shown in FIG. Hereinafter, an example of a technique for obtaining a semiconductor device as a micro device will be described with reference to a flowchart of FIG.

First, in step 301 of FIG.
A metal film is deposited on the wafers of the lot. In the next step 302, a photoresist is applied on the metal film on the wafer of the one lot. Then, step 303
In the above, using the exposure apparatus shown in FIG. 1, an image of a pattern on a mask (reticle) is sequentially transferred to each shot area on one lot of wafers via its projection optical system (projection optical unit) PL. Is done. Then, step 3
After the development of the photoresist on the wafer of the lot in step 04, the circuit corresponding to the pattern on the mask is etched in step 305 by using the resist pattern as a mask on the wafer of the lot. A pattern is formed in each shot area on each wafer. Thereafter, a device such as a semiconductor element is manufactured by forming a circuit pattern of an upper layer and the like. According to the above-described semiconductor device manufacturing method, a semiconductor device having an extremely fine circuit pattern can be obtained with high throughput.

In the above-described embodiment, an example is shown in which g-line light, h-line light, and i-line light are used as the exposure light. Only the h-line, the g-line and the h-line, and the h-line and the i-line can be used as the exposure light. Further, KrF excimer laser supplying light of 248nm as a light source, ArF excimer laser supplying light of 193 nm, may be used F ₂ laser etc. for supplying light of 157nm as a light source.

In the above embodiment, the lens is supported by surface contact. However, the present invention is not limited to this.
For example, a lens can be supported at a plurality of points at three or more locations. Further, in the above embodiment, the lens is supported by planar contact, but is not limited thereto.
For example, it can be supported by a curved surface contact according to the curved surface of the lens.

In the above-described embodiment, a part of the lens is cut out. However, the lens can be supported according to the present invention without being cut out. Further, in the above embodiment, only the lens on the plate side is supported according to the present invention, but the lens on the mask side can be supported if necessary. Further, in the above embodiment, the enlargement projection optical system is used, but a reduction projection optical system may be used. In this case, the enlargement side becomes the mask side lens.

In the above embodiment, the mask is set along the vertical plane and the plate is set along the horizontal plane. However, the present invention is not limited to this, and both the mask and the plate can be set along the horizontal plane. A configuration for setting is also possible. Further, in the above-described embodiment, the present invention is applied to the projection optical system having the enlargement magnification. However, the invention is not limited to this, but is applied to the projection optical system having the same magnification or the reduction magnification. You can also.

In the above embodiment, the device pattern is formed by one scanning exposure. However, the present invention is not limited to this. By repeating the scanning exposure a plurality of times, a larger area can be obtained by screen synthesis. A device pattern can also be formed. In this case, the shape of the illumination area formed on the mask is, for example, a trapezoid-like slit extending elongated in one direction.

[0055]

As described above, in the catadioptric projection optical system of the present invention, a projection field of view of a large size is secured along one direction, and the imaging performance such as deformation due to the weight of the lens component is improved. Can be favorably suppressed. Also,
In the exposure apparatus of the present invention, a large-area device pattern can be formed by one scanning exposure using a catadioptric projection optical system having a projection field of a large dimension along one direction.

[Brief description of the drawings]

FIG. 1 is a view schematically showing a configuration of an exposure apparatus including a projection optical system according to an embodiment of the present invention. FIG. 2 is a diagram schematically illustrating a configuration of a projection optical system in FIG. 1.

FIG. 2 is a diagram schematically showing a configuration of a projection optical system of FIG.

FIG. 3 is a diagram illustrating an effective area, a support area, and a cut-out ablation area of the lens according to the application of the present invention.

FIG. 4 is a perspective view illustrating a lens support mode according to the application of the present invention.

FIG. 5 is a view of a support member viewed from a plate side along an optical axis of the lens of FIG. 4;

FIG. 6 is a plan view illustrating a supporting form of the lens 11 for coping with deflection.

FIG. 7 is a diagram showing a flowchart of an example of a technique for obtaining a liquid crystal display element as a micro device.

FIG. 8 is a diagram showing a flowchart of an example of a technique for obtaining a semiconductor device as a micro device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 light source 2 elliptical mirror 4 collimating lens 5 wavelength selection filter 6 fly-eye lens 7 aperture stop 8 condenser optical system M mask MS mask stage PL projection optical system P plate PS plate stage

Claims (10)

[Claims] 1. A catadioptric projection comprising at least one concave reflecting mirror and a plurality of lens components, and projecting an image of a slit-like pattern extending along a predetermined direction on a first surface onto a second surface. In the optical system, the optical system is disposed at a position relatively close to the first surface or the second surface, outside the effective region through which the imaging light flux contributing to the formation of the image of the slit-shaped pattern passes, and in the effective region. At least one supported inside the circumscribed circular area
H has a maximum effective radius (radius of the circular region) of the lens component L1 and a distance between a support point closest to the optical axis of the lens component L1 and the optical axis. The projection optical system satisfies the following condition: X <0.75H. 2. The projection optical system according to claim 1, wherein the lens component L1 is disposed on an enlargement side of the projection optical system with an optical axis extending along a direction of gravity. . 3. The lens component L1 has a cutout shape excluding the effective area and a support area outside the effective area, and is supported by a holding member abutting the support area. The projection optical system according to claim 1. 4. The projection optical system according to claim 3, wherein a contact portion of the lens component L1 with the support region is formed in a planar shape. 5. A plane perpendicular to the optical axis of a cut-out area of the lens component L1, wherein the total projected area of the lens component L1 onto a plane perpendicular to the optical axis of the effective area and the support area is S1. 5. The projection optical system according to claim 3, wherein a condition of S1 <S2 is satisfied when an area projected on the projection optical system is S2. 6. The projection optical system according to claim 1, wherein said second surface side and said first surface side are telecentric. 7. The projection optical system according to claim 1, further comprising: an illumination optical system configured to illuminate a mask set on the first surface. An exposure apparatus for projecting and exposing a pattern formed on the mask to the photosensitive substrate while relatively moving the mask and the photosensitive substrate set on the second surface. 8. The exposure apparatus according to claim 7, wherein the illumination optical system illuminates the mask with light having a wavelength smaller than 450 nm. 9. A catadioptric projection system comprising at least one concave reflecting mirror and a plurality of lens components and projecting an image of a slit-like pattern extending along a predetermined direction on a first surface onto a second surface. A projection optical system, comprising: an optical system having at least one lens component having a predetermined portion cut out, leaving an effective area through which an imaging light beam contributing to formation of an image of the slit pattern passes. 10. An exposure method for projecting and exposing a pattern of a mask set on the first surface to a substrate set on the second surface, wherein the pattern of the mask is illuminated. An exposure method for projecting the illuminated pattern onto the substrate via the projection optical system according to any one of the above.