WO2002103431A1

WO2002103431A1 - Catadioptric system and exposure system provided with the system

Info

Publication number: WO2002103431A1
Application number: PCT/JP2002/005259
Authority: WO
Inventors: Tomowaki Takahashi
Original assignee: Nikon Corporation
Priority date: 2001-06-14
Filing date: 2002-05-30
Publication date: 2002-12-27
Also published as: JP4780364B2; JP2002372668A

Abstract

A catadioptric system comprising a first image forming optical system (G1) having a concave reflection mirror (CM2) and a plane reflection mirror (M1) and used to form the first intermediate image of a first plane (R) based on light from the first plane, a second image forming optical system (G2) having a concave reflection mirror (CM3) and a plane reflection mirror (M4) and used to form the second intermediate image of the first plane based on light via the first image forming optical system, and a third refractive type image forming optical system (G3) for forming the final image of the first plane on a second plane (W) based on light via the second image forming optical system.

Description

FIELD OF THE INVENTION

The present invention relates to a catadioptric optical system and an exposure apparatus having the optical system, and particularly to a high-resolution anti-reflection refraction which is optimal for an exposure apparatus used for manufacturing a semiconductor device or the like by a photolithographic process. Projection optical system.

Rice field

Background art

In recent years, in the manufacture of semiconductor elements and the manufacture of semiconductor chip mounting substrates, miniaturization has been further advanced, and a projection optical system with higher resolution has been required for an exposure apparatus for printing a pattern. To satisfy this demand for high resolution, the wavelength of the exposure light must be shortened and the NA (numerical aperture of the projection optical system) must be increased. However, as the wavelength of the exposure light becomes shorter, the types of optical glass that can withstand practical use are limited due to light absorption. For example, at wavelengths below 180 nm, the only viable glass material is fluorite.

In this case, if the projection optical system is composed of only refractive optical members (lenses, parallel plane plates, etc.), it is impossible to correct chromatic aberration with the formed refractive optical system. In other words, it is very difficult to configure a projection optical system having the required resolution with only a refractive optical member. On the other hand, attempts have been made to construct a projection optical system using only reflecting optical members, that is, reflecting mirrors.

However, in this case, the reflection type projection optical system to be formed becomes large and the reflection surface needs to be made aspherical. It is extremely difficult to make the reflecting surface aspherical with high precision in terms of manufacturing. Therefore, a combination of a refraction optical member made of optical glass that can withstand the use of short-wavelength light and a reflecting mirror is required. Various catadioptric reduction optical systems have been proposed.

Among them, Japanese Patent Application Laid-Open No. Hei 4-237472 and U.S. Pat. No. 4,779,966 discloses that an intermediate image is formed only once using only one concave reflecting mirror. There is known a catadioptric optical system of the following type. In this type of catadioptric system, the reciprocating optical system including the concave reflecting mirror includes only a negative lens and does not include a refractive optical member having a positive power. As a result, the diameter of the concave reflector tends to increase because the light beam enters the concave reflector in a spread state.

In particular, in the optical system disclosed in Japanese Patent Application Laid-Open No. 4-2324272, a reciprocating optical system including a concave reflecting mirror has a completely symmetric configuration. In this case, the generation of aberrations in the reciprocating optical system is minimized, and the burden of correcting aberrations in the subsequent refractive optical system is reduced. However, the adoption of a symmetrical reciprocating optical system made it difficult to ensure a sufficient working distance near the first surface, and had to use a half prism to split the optical path.

Further, in the optical system disclosed in U.S. Pat.No. 4,779,966, a concave reflecting mirror is used for a secondary image forming optical system disposed behind a position where an intermediate image is formed. I have. In this case, in order to secure the required brightness of the optical system, the light beam is incident on the concave reflecting mirror in a spread state. As a result, the diameter of the concave reflecting mirror tends to be large, and it has been difficult to reduce its size. On the other hand, a type of reflective refraction optical system that forms an intermediate image only once using a plurality of reflecting mirrors is also known. In this type of catadioptric optical system, there is a possibility that the number of lenses in the refractive optical system can be reduced. However, this type of catadioptric optical system has the following disadvantages.

In a catadioptric optical system of the type in which the reciprocating optical system having the above-described configuration is arranged on the second surface side, which is the reduction side, the second surface (wafer) after being reflected by the reflector due to reduction magnification. Surface) must be long enough. And can not. For this reason, it was not possible to insert too many lenses into this optical path, and the brightness of the obtained optical system had to be limited. Further, even if an optical system having a high numerical aperture can be realized, since many refractive optical members are arranged in an optical path of a limited length, the second surface, the wafer surface, and the most The distance from the two lens surfaces, the so-called working distance WD, could not be secured long enough.

In conventional catadioptric systems, it is necessary to bend the optical path and inevitably have multiple optical axes (refer to straight lines that connect the centers of curvature of the refractive or reflective surfaces that make up the optical system). become. As a result, a plurality of lens barrels were required to form the optical system, and it became extremely difficult to adjust the optical axes with each other, and a high-precision optical system could not be realized. By using a pair of reflecting mirrors having an opening (light transmitting part) at the center, a catadioptric system of a type in which all optical members are arranged along a single linear optical axis is also possible. . However, in this type of catadioptric system, it is necessary to shield the central light beam, that is, the central shield, in order to block unnecessary light traveling along the optical axis without being reflected by the reflecting mirror. As a result, there is an inconvenience that the contrast is reduced in a specific frequency pattern due to the central shielding.

In addition, the conventional catadioptric system could not secure a position where an effective field stop and aperture stop should be installed. Further, as described above, the working distance cannot be ensured sufficiently long in the conventional catadioptric optical system. Further, as described above, in the conventional catadioptric system, the concave reflecting mirror is easily enlarged, and the optical system cannot be downsized.

Further, in the conventional catadioptric optical system, the number of lenses tends to increase. In this case, especially in the optical system for F ₂ excimer laser, It is difficult to improve the performance of the antireflection film to be formed, and the amount of light used is likely to be attenuated. Also, in order to realize a high-performance, high-precision optical system, it is necessary to reduce the distance between the object plane and the image plane. However, this distance is not sufficiently small in the conventional catadioptric optical system. Disclosure of the invention

The present invention has been made in view of the above problems, and has a simple configuration in which the distance between the object plane and the image plane is small and the number of lenses is small, for example, vacuum ultraviolet light having a wavelength of 180 nm or less. It is an object of the present invention to provide a catadioptric optical system capable of achieving a high resolution of 0.1 or less using light in a wavelength range.

Further, the present invention can secure a position where an effective field stop and an aperture stop should be installed. For example, 0.1 z / m is used by using light in a vacuum ultraviolet wavelength region having a wavelength of 180 nm or less. It is an object of the present invention to provide a catadioptric optical system capable of achieving the following high resolution.

In addition, the present invention can ensure a sufficiently long working distance, for example, achieving a high resolution of 0.1 m or less using light in a vacuum ultraviolet wavelength range of 180 nm or less. The purpose is to provide a catadioptric system that can.

In addition, the present invention can reduce the size of the optical system by suppressing the enlargement of the concave reflecting mirror. For example, the present invention uses a light in a vacuum ultraviolet wavelength range of 180 nm or less to achieve a diameter of 0.1 m or less. An object of the present invention is to provide a catadioptric optical system capable of achieving high resolution.

Further, the catadioptric optical system of the present invention is used as a projection optical system, for example, by using exposure light having a wavelength of 180 nm or less to perform good projection exposure with a high resolution of 0.1 m or less. It is an object of the present invention to provide an exposure apparatus capable of performing the following. In order to solve the above problem, a first invention of the present invention has at least one concave reflecting mirror and at least one flat reflecting mirror, and based on light from the first surface, (1) a first imaging optical system for forming an intermediate image, and

A second reflecting mirror having at least one concave reflecting mirror and at least one flat reflecting mirror for forming a second intermediate image of the first surface based on light passing through the first imaging optical system; Imaging optics,

A refraction-type third imaging optical system for forming a final image of the first surface on the second surface based on light passing through the second imaging optical system. A catadioptric system is provided.

According to a preferred aspect of the first invention, all optical members except the plane reflecting mirror of the first imaging optical system and all optical members except the plane reflecting mirror of the second imaging optical system are linear. All the optical members of the third imaging optical system are linearly extended so as to be orthogonal to the first optical axis. The light from the first surface is disposed along a second optical axis, and the light from the first surface passes through the one plane reflecting mirror and the one concave reflecting mirror in the first imaging optical system sequentially, and the first intermediate image And the light passing through the first imaging optical system forms the second intermediate image via one planar reflecting mirror and one concave reflecting mirror of the second imaging optical system in order. . '

Further, according to a preferred aspect of the first invention, it is preferable that the first imaging optical system has at least one negative lens component disposed immediately before the concave reflecting mirror. Preferably, the second imaging optical system has at least one negative lens component disposed immediately before the concave reflecting mirror. Further, the catadioptric system is preferably telecentric on at least one of the first surface side and the second surface side. Further, it is preferable that a field lens is disposed in an optical path between the second imaging optical system and the third imaging optical system. Further, according to a preferred aspect of the first invention, a field lens is disposed in an optical path between the first imaging optical system and the second imaging optical system. In this case, at least one of the field lenses disposed in the optical path between the first imaging optical system and the second imaging optical system is the first imaging optical system. It is preferable to have a partially cut-out shape in order to pass only the light reflected from the concave reflecting mirror without passing the light incident on the concave reflecting mirror of the system. In addition, at least one of the field lenses disposed in an optical path between the first imaging optical system and the second imaging optical system includes the lens of the first imaging optical system. It is preferable that both the light incident on the concave reflecting mirror and the light reflected from the concave reflecting mirror are transmitted.

According to a second aspect of the present invention, an illumination system for illuminating the mask set on the first surface, and an image of a pattern formed on the mask is formed on a photosensitive substrate set on the second surface. An exposure apparatus comprising: the catadioptric optical system according to the first aspect of the present invention. According to a preferred aspect of the second invention, the mask and the photosensitive substrate are relatively moved with respect to the catadioptric system to scan and expose the pattern of the mask on the photosensitive substrate. preferable. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a diagram for explaining a basic configuration of a catadioptric optical system of the present invention.

FIG. 2 is a diagram schematically illustrating an overall configuration of an exposure apparatus including a catadioptric optical system according to each embodiment of the present invention as a projection optical system.

FIG. 3 is a diagram showing a positional relationship between a rectangular exposure area (ie, an effective exposure area) formed on a wafer and a reference optical axis.

FIG. 4 is a diagram of a catadioptric optical system (projection optical system PL) according to the first embodiment. FIG.

FIG. 5 is a diagram illustrating the lateral aberration of the catadioptric optical system according to the first embodiment: FIG. 6 is a diagram illustrating the lateral aberration of the catadioptric optical system according to the first embodiment ₍ FIG. FIG. 9 is a diagram showing a lens configuration of a catadioptric optical system (projection optical system PL) according to a second example.

Figure 8 is a diagram showing lateral aberration of such catadioptric optical system in the second embodiment <9 is a diagram showing lateral aberration of the catadioptric optical system according to the second embodiment _(FIG. 1 0 This is a flowchart of a technique for obtaining a semiconductor device as a micro device.

FIG. 11 is a flowchart of a method for obtaining a liquid crystal display element as a micro device. Embodiment of the Invention

FIG. 1 is a diagram for explaining a basic configuration of a catadioptric optical system of the present invention. In FIG. 1, the catadioptric optical system of the present invention is applied to a projection optical system of a scanning exposure type exposure apparatus. As shown in FIG. 1, the catadioptric system of the present invention includes a first imaging optical system G1 that forms a first intermediate image of a pattern of a reticle R as a projection master disposed on a first surface. ing. Note that the first imaging optical system G1 has at least one concave reflecting mirror and at least one plane reflecting mirror, that is, a first plane reflecting mirror M1 and a second concave reflecting mirror CM2. In the first imaging optical system G1, light from the reticle R forms a first intermediate image via the first plane reflecting mirror M1 and the second concave reflecting mirror CM2.

The light passing through the first imaging optical system G1 forms a second intermediate image of the pattern of the reticle R via the second imaging optical system G2. The second imaging optical system G2 has at least one concave reflecting mirror and at least one plane reflecting mirror, that is, a third concave reflecting mirror CM3 and a fourth plane reflecting mirror M4. Therefore, in the second imaging optical system G2, the light passing through the first imaging optical system G1 is reflected by the third concave surface. A second intermediate image is formed via the projection mirror CM3 and the fourth plane reflection mirror M4. The light that has passed through the second imaging optical system G2 passes through a refraction-type third imaging optical system G3 having a plurality of refraction optical members without including a reflecting mirror to form the final image of the reticle-scale pattern. It is formed on a wafer W as a photosensitive substrate disposed on the second surface. In an exposure apparatus equipped with the catadioptric optical system of the present invention as a projection optical system, a rectangular illumination area IR and an effective exposure area ER are moved while moving a reticle R and a wafer W in a predetermined direction (scan direction). Is performed based on the scanning exposure.

According to a specific embodiment, all the optical members of the first imaging optical system G1 except for the first plane reflecting mirror M1 and all of the second imaging optical system G2 except for the fourth plane reflecting mirror M4 Are arranged along a single first optical axis AX1 extending linearly. All the optical members of the third imaging optical system G3 are arranged along a single second optical axis AX2 that extends linearly so as to be orthogonal to the first optical axis AX1. I have. The first plane reflecting mirror M 1 and the fourth plane reflecting mirror M 4 can be integrally formed as front and back mirrors. When the first plane reflecting mirror M1 and the fourth plane reflecting mirror M4 are integrally formed, the precision of the front and back surfaces is good and the manufacturing is easy. Further, when the first plane reflecting mirror Ml and the fourth plane reflecting mirror M4 are arranged at predetermined positions, an angle adjustment is required, but if they are integrally formed, the first plane reflecting mirror M4 Even if 1 is disposed with an error in the minus direction from the predetermined angle, the fourth plane reflecting mirror M 4 cancels the error in the plus direction from the predetermined angle, and the fourth plane reflecting mirror M 4 It can be incident at an angle.

According to a more specific mode, the field lens FL is disposed in the optical path between the first imaging optical system G1 and the second imaging optical system G2. Here, the field lens FL has a function of matching and connecting the first imaging optical system G 1 and the second imaging optical system G 2 without actively contributing to the formation of the first intermediate image. At least one of the field lenses FL Lens has a partially cut-out shape to allow only the reflected light from the second concave reflecting mirror to pass without passing the light incident on the second concave reflecting mirror of the first imaging optical system G1. Have.

At least one of the field lenses FL is formed so as to transmit both the light incident on the second concave reflecting mirror of the first imaging optical system G1 and the reflected light from the second concave reflecting mirror. ing. In addition, a field lens is arranged in the optical path between the second imaging optical system G2 and the third imaging optical system G3 as needed.

Further, according to a specific embodiment, immediately before the second concave reflecting mirror CM2 of the first imaging optical system G1 and the third concave reflecting mirror CM3 of the second imaging optical system G2, At least one negative lens component is arranged. With this configuration, even if the refractive optical member (lens component) is formed of a single kind of optical material, it is possible to satisfactorily correct chromatic aberration. Further, it is possible to satisfactorily simultaneously correct the axial chromatic aberration and the chromatic difference of magnification.

Further, a field stop FS defining an image area formed by the catadioptric optical system is provided near the field lens FL between the first imaging optical system G1 and the second imaging optical system G2, or the second stop. It can be arranged near the field lens between the imaging optical system G2 and the third imaging optical system G3. In this case, it is possible to adopt a configuration in which the illumination optical system does not need to have a field stop. Further, an aperture stop AS can be arranged in the optical path of the third imaging optical system G3. As described above, in the catadioptric optical system of the present invention, both the first imaging optical system G1 and the second imaging optical system G2 have at least one concave reflecting mirror and at least one flat reflecting mirror. And the third imaging optical system G3 constitutes a refraction type optical system. Therefore, according to a typical embodiment, the first imaging optical system G1 and the second imaging optical system G2 are arranged along the first optical axis AX1, and the third imaging optical system G3 is It is arranged along the second optical axis AX2 orthogonal to the first optical axis AX1. The reticle R and the wafer W have the second optical axis AX 2 Will be arranged along.

Thus, in the present invention, only the third imaging optical system G3 is disposed along the second optical axis AX2 on which the reticle R and the wafer W are disposed, and the first imaging optical system G1 and the second imaging optical system G2 are arranged along a first optical axis AX1 orthogonal to the second optical axis AX2. Therefore, in the present invention, the distance between the reticle R and the wafer W, that is, the distance between the object plane and the image plane can be set small, and a high-performance and high-precision optical system can be realized. In particular, by making the first optical axis AX1 orthogonal to the second optical axis AX2, the adjustment work between the optical axes becomes easy, and it is easy to realize a high-performance and high-precision optical system. Become.

Also, by configuring the first imaging optical system G1 and the second imaging optical system G2 as catadioptric optical systems, good correction of chromatic aberration can be achieved even if the lens component is formed of a single type of optical material. It becomes possible. Further, at least one negative lens component is arranged immediately before the second concave reflecting mirror CM2 of the first imaging optical system G1 and immediately before the third concave reflecting mirror CM3 of the second imaging optical system G2. This makes it possible to satisfactorily correct axial chromatic aberration and magnification chromatic aberration at the same time.

Further, in the present invention, the Petzval sum that tends to be positive because the refractive optical system portion of the third imaging optical system G3 has a positive refractive power (power) is converted to the first imaging optical system G1 and the second optical system. (2) The negative Petzval sum of the concave reflecting mirror portions (CM 2, CM 3) in the imaging optical system G 2 cancels out and the whole Petzval sum can be completely suppressed to zero. Furthermore, in the present invention, as shown in each real施例described below, since little simple configuration of lenses is enabled, for example, F ₂ be an excimer laser beam rather difficulty leads to attenuation of the use quantity, A decrease in throughput of the exposure apparatus can be avoided.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 2 shows a catadioptric optical system according to each embodiment of the present invention as a projection optical system. FIG. 1 is a view schematically showing an overall configuration of an exposure apparatus provided with _u . Note that in FIG. 2, the Z axis is parallel to the reference optical axis of the catadioptric system constituting the projection optical system PL, that is, the second optical axis AX 2, and the plane is perpendicular to the reference optical axis AX 2. The Y axis is set parallel to the paper and the X axis is set perpendicular to the paper.

Exposing the illustrated apparatus, a light source 1 0 0 for supplying illumination light in the ultraviolet region, and a F ₂ laser light source (oscillation center wavelength of 1 5 7. 6 nm). The light emitted from the light source 100 uniformly illuminates a reticle (mask) R on which a predetermined pattern is formed via an illumination optical system IL. The optical path between the light source 100 and the illumination optical system IL is sealed by a casing (not shown), and the space from the light source 100 to the optical component closest to the reticle side in the illumination optical system IL. Is replaced by an inert gas such as helium gas or nitrogen, which is a gas having a low absorptance of exposure light, or is kept almost in a vacuum state.

The reticle R is held on a reticle stage RS via a reticle holder RH in parallel with the XY plane. A pattern to be transferred is formed on the reticle R, and a rectangular pattern region having a long side along the X direction and a short side along the Y direction in the entire pattern region is illuminated. The reticle stage RS can be moved two-dimensionally along the reticle plane (that is, the XY plane) by the action of a drive system (not shown), and its position coordinates are transmitted to the interferometer RIF using the reticle moving mirror RM. Thus, it is configured to be measured and controlled in position.

Light from the pattern formed on the reticle R forms a reticle pattern image on the wafer W as a photosensitive substrate via the catadioptric projection optical system PL. The wafer W is held in parallel with the XY plane on a wafer stage WS via a wafer table (wafer holder) WT. Then, the wafer W has a long side along the X direction and a short side along the Y direction so as to optically correspond to the rectangular illumination area on the reticle R. A pattern image is formed in the rectangular exposure area. The wafer stage WS can be moved two-dimensionally along the wafer surface (that is, the XY plane) by the action of a drive system (not shown), and its position coordinates are measured by an interferometer WIF using a wafer moving mirror WM. In addition, the position is controlled.

FIG. 3 is a diagram showing a positional relationship between a rectangular exposure area (ie, an effective exposure area) formed on a wafer and a reference optical axis. As shown in FIG. 3, in each embodiment, in the circular area (image circle) IF having a radius A (corresponding to the maximum image height) centered on the reference optical axis AX2, the reference optical axis AX2 is — A rectangular effective exposure area ER having a desired size is set at a position eccentric in the Y direction. Here, the length in the X direction of the effective exposure area ER is LX, and the length in the Y direction is LY.

Therefore, as shown in FIG. 1, on the reticle R, a rectangular illumination area IR having a size and shape corresponding to the effective exposure area ER is formed at a position decentered in the + Y direction from the reference optical axis AX2. It will be. In other words, within a circular area having a radius B (corresponding to the maximum object height) centered on the reference optical axis AX2, a desired size is set at a position eccentric in the + Y direction from the reference optical axis AX2. A rectangular illumination area IR is set. '

Further, in the exposure apparatus shown in the figure, the optical member (the first plane reflecting mirror Ml in each embodiment) arranged closest to the reticle side among the optical members constituting the projection optical system PL is arranged closest to the wafer side. The projection optical system PL is configured so as to keep the interior of the projection optical system PL airtight between the optical member (the lens L312 in the first embodiment and the lens L311 in the second embodiment). The gas inside is replaced by an inert gas such as helium gas or nitrogen, or is maintained in a substantially vacuum state.

Furthermore, the narrow optical path between the illumination optical system IL and the projection optical system PL 丄

RS, etc. are placed: A casing (not shown) that hermetically surrounds the reticle R and reticle stage RS is filled with an inert gas such as nitrogen or helium gas, or almost completely. It is kept in a vacuum state.

In a narrow optical path between the projection optical system PL and the wafer W, a casing (not shown) for enclosing and enclosing the wafer W and the wafer stage WS in which the wafer W and the wafer stage WS are arranged. Is filled with an inert gas such as nitrogen or helium gas, or is kept almost in a vacuum state. Thus, an atmosphere in which the exposure light is hardly absorbed is formed over the entire optical path from the light source 100 to the wafer W.

As described above, the illumination area on the reticle R defined by the projection optical system PL and the exposure area on the wafer W (ie, the effective exposure area ER) are rectangular with short sides along the Y direction. . Therefore, while controlling the positions of the reticle R and the wafer W using a drive system and interferometers (RIF, WIF), etc., along the short side direction of the rectangular exposure area and the illumination area, that is, along the Y direction. By moving (scanning) the reticle stage RS and the wafer stage WS and, consequently, the reticle R and the wafer W in opposite directions (ie, in opposite directions), the long side of the exposure area on the wafer W is obtained. The reticle pattern is scanned and exposed to a region having a width equal to the length of the wafer W and a length corresponding to the scanning amount (movement amount) of the wafer W.

In each embodiment, the projection optical system PL including the catadioptric optical system of the present invention is a catadioptric first imaging optical system for forming a first intermediate image of the pattern of the reticle R disposed on the first surface. A system G 1, a catadioptric second imaging optical system G 2 for forming a second intermediate image of the pattern of the reticle R based on light passing through the first imaging optical system G 1, The final image of the reticle pattern on the wafer W placed on the second surface based on the light passing through the imaging optical system G2 (Refraction type third imaging optical system G3) for forming (reduced image of the reticle pattern).

In each embodiment, all optical members of the first imaging optical system G1 except for the first plane reflecting mirror M1 and all optical members except for the fourth plane reflecting mirror M4 of the second imaging optical system G2. The member is arranged along the first optical axis AX1. Further, all the optical members constituting the third imaging optical system G3 are arranged along a second optical axis AX2 orthogonal to the first optical axis AX1. Further, a first field lens is disposed in an optical path between the first imaging optical system G 1 and the second imaging optical system G 2, and the second imaging optical system G 2 and the third imaging optical system G 2 A second field lens is arranged in the optical path between 3 and.

In each embodiment, fluorite (C a F ₂ crystal) is used for all refractive optical members (lens components) constituting the projection optical system PL. The oscillation center wavelength of F ₂ laser beam as the exposure light is 1 5 7. 6 nm, 1 5 7. 6 refractive index of the C a F ₂ in the vicinity nm is, + 1 ρπι wavelength change per 2 . 45 X 1 0- ^s varies at a rate of, - 1 pm per wavelength change + 2. changes at a rate of 4 5 X 1 0- ^6. In other words, the dispersion (dnZciA) of the refractive index of C a F ₂ around 15.76 nm is 2.45 X 10 "pm.

Thus, in each embodiment, the refractive index of the C a F ₂ with respect to the center wavelength of 1 5 7. 6 nm is 1.5 6 0 0 0 0. And the refractive index of C a F ₂ with respect to 15.7.6 nm + 0.4 pm = 15.7.604 nm is 1.55 999 9 0 2 = 1.559 9 9 9 And the refractive index of C a F ₂ for 1 57.6 n m-0.4 pm = 1 5 7.59 9 5 = nm is 1.56 0 00 00 98 = 1.5 600 0 1 It is.

In each embodiment, the height of the aspheric surface in the direction perpendicular to the optical axis is y, and the aspheric surface extends along the optical axis from the tangent plane at the vertex of the aspheric surface to the position on the aspheric surface at the height y. The distance (sag amount) is z, the vertex curvature radius is r, and the circle When the cone coefficient is κ and the η-order aspheric coefficient is C „, it is expressed by the following equation (a).

z = (yr) / [1 + {1 - (1 + c) · yV r 2} 1/2 ]

_{^{+ C 4 · y 4 + C}} y 6 + C 8 · y 8 + C 10 - y '. (A)

In each embodiment, an asterisk (*) is attached to the right side of the surface number on the lens surface formed into an aspherical shape.

(First embodiment)

FIG. 4 is a diagram illustrating a lens configuration of a catadioptric optical system (projection optical system P L) according to the first example. In the catadioptric optical system shown in FIG. 4, the first imaging optical system G 1 has a convex surface on the side of the first plane reflecting mirror M 1 and the first plane reflecting mirror M 1 along the traveling direction of light from the reticle side. , A positive meniscus lens L 11, a biconcave lens L 12, and a second concave reflector CM 2 having a concave surface facing the first plane reflector M l. Here, the positive meniscus lens L11, the biconcave lens L12, and the second concave reflecting mirror CM2 are arranged in order from the right side in the figure along the horizontal first optical axis AX1 in the figure.

The second imaging optical system G2 is a negative meniscus lens L2 having a concave surface facing the first imaging optical system G1 along the light traveling direction from the first imaging optical system G1. 1, a third concave reflecting mirror CM3 having a concave surface facing the first imaging optical system G1, and a fourth flat reflecting mirror M4. Here, the negative meniscus lens L 21 and the third concave reflecting mirror CM 3 are arranged in order from the left side in the figure along the first optical axis AX 1.

Further, the third imaging optical system G 3 includes, in order from the reticle side, a positive meniscus lens L 31 having a convex surface facing the reticle side and a negative meniscus lens L 3 2 having an aspherical concave surface facing the reticle side. A negative meniscus lens L33 with an aspheric concave surface facing the wafer side, a biconvex lens L34, a negative meniscus lens L35 with an aspheric convex surface facing the reticle side, and a reticle side ₁ l _β b Positive meniscus lens L 36 with convex surface facing, aperture stop AS, biconvex lens L 37 with aspherical convex surface facing reticle side, positive meniscus lens L with convex surface facing reticle side 38, a biconvex lens L39 with an aspherical convex surface facing the wafer side, a biconvex lens L310, and a positive meniscus lens L311 with an aspherical concave surface facing the wafer side. It is composed of a biconvex lens L312. Here, the lenses L31 to L312 are arranged in order from the upper side (reticle side) in the figure along the second vertical optical axis AX2 in the figure. In the optical path between the first image forming optical system G 1 and the second image forming optical system G 2, the first image forming optical system A first field composed of a positive meniscus lens L 41 having a concave surface facing the optical system G 1 side and a partial lens L 42 of a positive meniscus lens having a convex surface facing the first imaging optical system G 1 side. A lens is located. That is, the positive meniscus lens L41 and the partial lens L42 of the positive meniscus lens are arranged in order from the left side in the figure along the first optical axis AX1.

Here, the positive meniscus lens L 41 is the same lens as the positive meniscus lens LI 1, and passes both the incident light to the second concave reflecting mirror CM 2 and the reflected light from the second concave reflecting mirror CM 2 . The partial lens L42 of the positive meniscus lens is a positive meniscus lens that passes only the light reflected from the second concave reflector CM2 without passing the light incident on the second concave reflector CM2. Has a partially cut-out shape.

In the optical path between the second imaging optical system G 2 and the third imaging optical system G 3, a biconvex lens L 51 having an aspherical convex surface facing the reticle side is arranged in order from the reticle side. A second field lens composed of a positive meniscus lens L 52 having a convex surface facing the reticle side and a positive meniscus lens L 53 having a non-spherical convex surface facing the wafer side is disposed. . Here, the lenses L51 to L5'3 are arranged in order from the upper side (reticle side) in the figure along the second optical axis AX2. _χ?

Therefore, in the first embodiment, after the light from the reticle R is reflected by the first plane reflecting mirror Μ1, it passes through the positive meniscus lens LI1 and the biconcave lens L12, and then passes through the second concave reflecting mirror CM2. Incident on. The light reflected by the second concave reflecting mirror CM2 forms a first intermediate image of a reticle pattern near the first field lens (L41, L42). Light from the first intermediate image formed near the first field lens (L41, L42) enters the third concave reflecting mirror CM3 via the negative meniscus lens L21.

The light reflected by the third concave reflecting mirror CM3 is incident on the fourth plane reflecting mirror M4 via the negative meniscus lens L21. The light reflected by the fourth plane mirror M4 forms a second intermediate image of the reticle pattern in the second field lens (L51 to L53). The light from the second intermediate image formed in the second field lens (L51 to L53) passes through each lens L3 that constitutes the third imaging optical system G3:! Through the process, a final image of the reticle pattern is formed on the wafer W.

The following Table (1) shows the values of the specifications of the catadioptric optical system according to the first example. In the main specifications in Table (1), λ is the center wavelength of the exposure light, jS is the projection magnification '(imaging magnification of the entire system), NA is the numerical aperture on the image side (Jehachi side), and A is Is the radius of the image circle IF on the wafer W, that is, the maximum image height, B is the maximum object height corresponding to the maximum image height A, LX is the dimension of the effective exposure area ER along the X direction (long side dimension) LY represents the dimension (short side dimension) of the effective exposure area ER along the Y direction.

In the optical member specifications in Table (1), the surface number of the first column is the order of the surface along the light traveling direction from the reticle side, and r of the second column is the radius of curvature (aspheric surface) of each surface. In the case of, the vertex curvature radius: mm), d in the third column indicates the on-axis spacing of each surface, that is, the surface spacing (mm), and n in the fourth column indicates the refractive index with respect to the center wavelength. Note that the sign of the surface distance d changes each time it is reflected. Therefore, the sign of the surface distance d is Negative in the optical path from the first concave reflecting mirror M1 to the second concave reflecting mirror CM2 and in the optical path from the third concave reflecting mirror CM3 to the fourth flat reflecting mirror M4, and positive in other optical paths. And

On the optical surface arranged along the first optical axis, the radius of curvature of the convex surface toward the left in the figure is positive, and the radius of curvature of the concave surface toward the left in the diagram is negative. Further, on the optical surface disposed along the second optical axis, the radius of curvature of the convex surface toward the reticle side (upper side in the figure) is positive, and the radius of curvature of the concave surface toward the reticle side is negative. In the following table (2), the above notation is the same.

(table 1 )

(Main specifications)

λ = 15.7 nm

β = 1/5

Ν Α = 0.845

A = 20 mm

Β = 100 mm

L Χ = 2 2 mm

L Y = 5.5 mm

(Optical component specifications)

Surface number r d n

(Reticle surface) 290.026586

1 oo (first plane reflector M 1)

2 -375.61418 -69.999996 1.560000 (Lens 1 1)

3 -8384.72157 -577.10812

4 3695.39575 -15.430078 1.560000 (Lens L 1 2) 5 -1011.27343 -20.000282

6 488. .06850 20 • 000282 (Second concave reflector CM

7 -1011.27343 15.430078 1.560000 (Lens, T19)

8 3695. 39575 577. 410812

9 -8384.72155 69.999996 (Lens' T4 1)

10 -375. 61418 1.000 000

11 523. 29394 26. 651917 (Lens L 4 2)

12 7089. 68959 776. 202894

13 -233. 13196 12.344063 (Lens 2 1)

14 -782.75388 20.000264

15 -397 .38457 -20 .000264 CD (3rd concave reflector CM

16 -782.75388 -12.344063 (Lens 2 1)

17.-233.13196-730.717730

18 oo 200. 000000 (4th plane reflector M 4)

19 * 485.08331 29. 459002 (Lens L5 1)

20 -3575. 98802 1. 000000

21 233. 35657 29. 671010 (Lens 5 2)

22 486.59435 92.567882

23 -2726.09488 15.000000 (Lens 5 3)

24 * -905.37791 189.879636

25 171.44052 18.057863 (Lens 3 1)

26 230.14097 81.533597

27 * -134.73026 23.510345 (Lens L32)

28 -3198. .32252 19.739819

29 200. .39557 15.000000 (Lens 3 3)

30 * 155. 44391 11.006083

31 214. .60791 43.765233 (Lens L3 4) 32 -552.06075 4.884579

33 * 273.28545 15.000000 1.560000 (Lens 3 5) 34 169.26001 49.818640

35 206.47284 28.337440 560000 (Lens L 3 6)

36 512.08579 56.625033

37 oo 29.862740 (Aperture stop AS)

38 * 307.92600 29.246184 1.560000 (Lens L3 7)

39 -1614.99027

40 339.56596 15.002529 1.560000 (Lens L 3 8) 41 428.85314

42 292.93034 55.380125 1.560000 (Lens 3 9) 43 * -365.29687 4.141093

44 394.28173 53.678655 1.560000 (Lens 3 1 0)

45 -1442.13457 2.718799

46 112.27860 28.030508 1.560000 (Lens L 3 1 1) 47 * 314.25185 6.015629

48 666.58142 53.355715 1.560000 (Lens 3 1 2)

49 -1471.85947 6.000000

(Wafer surface)

(Aspheric surface night)

1 9 faces

κ = 0. 0 0 0 0 0 0

_{C 4 = - 0. 1 7 8} 1 49 X 1 0- 8 C 6 = 0 4 0 5 0 49 X 1 0- 13

_{C 8 = 0. 46 8 5 1} 6 X 1 0 - '8 C 10 = 0 8 8 5 9 2 3 X 1 0- 24

24 faces OTXSSTT ^ T0-= ⁹ 3 8-0 TX 9 ε S 6 I ^ '0 =' o

o o o o o o · 0 = ¾

s ε

01

u-0 TXS 2 T9 0 2 0-Dtl-0 TX ^ T 0 8 9 _8o- = ^s 0

0 Τ XS 9 8 0 0 9 ■ 0 - 9 D i - 0 IXIZ ΐ s ε .0 D

o o o o o o .0 =

8 ε

_{0, - o I x ^ ΐ} ε s ε T 'o:? 01 0 91 - 0 IX 6 ^ 2 9 T 2 0 _ = s

I, -0 TX 9 SZTI-0: ⁹ i-0 TX 6 9 9 Z 8 e 0 D

O O O O O O 0 = y

91

u-0 TXZ 2 I ^ Z 9 '0 ^J, 3 9.- 0 1 X 9 0 9 8 ^ ^ • 0-= ⁸ 0 _Z1 --0 TX ■ 0: ⁹ i-0 IX 980 T 22' 0-D

O O O O O O .0 = ¾

Deer o ε 01

0 Τ Χ ΐ Ζ Τ ^ 2 8-0:. '0 9i- 0 1 X 8 8 1 9 8 2 0 = ⁸ O 0 IX 6 0 "[' 0: ⁹ D i-0 TXT 8 6 0 ST 0 = D

O O O O O O 0 = y

u -0 Τ Χ 6 6 Τ 9 Τ ^ '0-01

0 _S1 -0 IX 6-0 = ⁸ D _ει -0 Τ Χ Τ 26 ΐ ε ^ ■ 0 = ⁹⁰ _Α -0 TX 66 08 TT-0 = 0

O O O O O O "0 = 5

6SZS0 / Z0df / X3d IZ c 0.40 3 1 64 X 1 0 -17 c 0.3.07 8 6 1 X 10

47 faces

K = 0. 0 0 0 0 0 0

_{C 4 - 0. 3 6 6 9} 3 2 X 1 0 "7 C 6 0. 4 5 8 2 58 X 1 0 - | 2 C a = - 0. 3 8 6 3 8 8 X 1 0 6 C 10 0 2 74 1 50 X 10- ^{| 9} Fig. 5 and Fig. 6 are diagrams showing lateral aberrations of the catadioptric optical system according to Example 1. In the aberration diagrams, Y represents the image height (mm). As can be seen from the aberration diagram, in the first embodiment, the exposure light having a wavelength width of 157.6 nm ± 0.4 pm, against the F ₂ laser beam of half width 0. 7 pm, this chromatic aberrations are satisfactorily corrected Togawakaru. Further, spherical aberration, coma, astigmatism, distortion (distortion aberration) is almost no aberration It has been confirmed that it is well corrected to a close state and has excellent imaging performance.

(Second embodiment)

FIG. 7 is a diagram illustrating a lens configuration of a catadioptric optical system (projection optical system PL) according to the second example. In the catadioptric optical system of FIG. 7, the first imaging optical system G 1 has a convex surface on the first plane reflecting mirror M 1 and the first plane reflecting mirror M 1 side along the light traveling direction from the reticle side. , A positive meniscus lens L 11, a biconcave lens L 12, and a second concave reflector CM 2 having a concave surface facing the first plane reflector M 1. Here, the positive meniscus lens L11, the biconcave lens L12, and the second concave reflecting mirror CM2 are arranged in order from the right side in the figure along the horizontal first optical axis AX1 in the figure.

The second imaging optical system G2 is a negative meniscus lens having a concave surface facing the first imaging optical system G1 along the light traveling direction from the first imaging optical system G1. L 2, a third concave reflecting mirror CM 3 having a concave surface facing the first imaging optical system G 1, and a fourth flat reflecting mirror M 4. Here, the negative meniscus lens 21 and the third concave reflecting mirror CM 3 are arranged in order from the left side in the figure along the first optical axis AX 1.

Further, the third imaging optical system G 3 includes, in order from the reticle side, a negative meniscus lens L 31 having a concave surface facing the reticle side, and a biconvex lens L 32 having an aspherical convex surface facing the reticle side. , A biconcave lens L33 with an aspheric concave surface facing the wafer side, a biconvex lens L34, a biconcave lens L35 with an aspheric convex surface facing the reticle side, and a convex surface facing the reticle side A positive meniscus lens L36, an aperture stop AS, a biconvex lens L37 with an aspheric convex surface facing the reticle side, and a biconvex lens L38 with an aspheric convex surface facing the wafer side. It is composed of a biconvex lens L39, a positive meniscus lens L310 with an aspheric concave surface facing the wafer side, and a biconvex lens L311. Here, the lenses L31 to L311 are arranged in order from the upper side (reticle side) in the figure along the second optical axis AX2, which is vertical in the figure.

In the optical path between the first imaging optical system G1 and the second imaging optical system G2, the first imaging optical system A first field composed of a positive meniscus lens L 41 having a concave surface facing the optical system G 1 side and a partial lens L 42 of a positive meniscus lens having a convex surface facing the first imaging optical system G 1 side. A lens is located. That is, the positive meniscus lens L41 and the partial lens L42 of the positive meniscus lens are arranged along the first optical axis AX1 from the left side in the figure.

Here, the positive meniscus lens L 41 is the same lens as the positive meniscus lens L 11, and passes both the light incident on the second concave reflecting mirror CM 2 and the reflected light from the second concave reflecting mirror CM 2 Let it. The partial lens L42 of the positive meniscus lens passes only the light reflected from the second concave reflecting mirror CM2 without passing the light incident on the second concave reflecting mirror CM2. The positive meniscus lens has a partially cut-out shape.

In the optical path between the second imaging optical system G2 and the third imaging optical system G3, a biconvex lens L51 having an aspherical convex surface facing the reticle side in order from the reticle side. In addition, a second field lens including a positive meniscus lens L52 having a convex surface facing the reticle side and a biconvex lens L53 having an aspherical convex surface facing the reticle side is arranged. Here, the lenses L51 to L53 are arranged in order from the upper side (reticle side) in the figure along the second optical axis AX2.

Accordingly, in the first embodiment, after the light from the reticle R is reflected by the first plane reflecting mirror M1, the light is reflected by the positive meniscus lens L1 and the biconcave lens L12, and the second concave reflecting mirror CM It is incident on 2. The light reflected by the second concave reflecting mirror CM2 forms a first intermediate image of a reticle pattern near the first field lens (L41, L42). Light from the first intermediate image formed near the first field lens (L41, L42) enters the third concave reflecting mirror CM3 via the negative meniscus lens L21.

The light reflected by the third concave reflecting mirror CM3 is incident on the fourth plane reflecting mirror M4 via the negative meniscus lens L21. The light reflected by the fourth plane reflecting mirror M4 forms a second intermediate image of a reticle pattern near the second field lens (L51 to L53). Light from the second intermediate image formed in the vicinity of the second field lens (L51 to L53) passes through each lens L31 to L31 constituting the third imaging optical system G3. Through the process, a final image of the reticle pattern is formed on the wafer W.

Table 2 below summarizes the data values of the catadioptric optical system according to the second example.

(Table 2)

(Main specifications) λ = 1 57.6 nm

β = 1 Z 5

N A = 0.884 5

A = 20 mm

B = 100 mm

L X = 2 2 mm

L Y = 5.5 mm

(Optical component specifications)

Surface number r d n

(Reticle surface) 290.027792

1 oo-10.000000 (first plane reflector M l)

2 -375.77476 -70.000000 1.560000 (Lens 1 1)

3 -8471.57979 -571.612419

4 880.34723 -20.000002 1.560000 (Lens 1 2)

5 -1526.15631-20.000068

6 430.44124 20.000068 (2nd concave reflector CM2)

7 -1526.15631 20.000002 1.560000 (Lens 1 2)

8 880.34723 571.612419

9 -8471.57979 69.999999 1.560000 (Lens 1)

10 -375.77476 1.000002

11 392.76058 40.629139 1.560000 (Lens 42) 12 1108.55246 695.632956

13 -228.90899 1.560000 (Lens 2 1) 14 -747.58067 20.000181

15 -395.97377 -20.000181 (3rd concave reflector CM 3)

16 -747.58067 -20.000000 1.560000 (Lens 2 1) 17 -228., 90899 -664.125014

18 oo 200. 000000 (4th plane mirror M4) o 1 丄, C:

D 乙 Π) Π: Q o ノノ no 6 Q 乙 9)) Q 6 Q ヽ)

o /!,

32 -208. .61721 43.802275

33 * -362. .74483 20. 000000

34 705. .62394 1.145699

35 210, .45845 20.000001 (]

36 348. .14561 29.558007

37 oo 8. 302787, | for?

38 * 348.07912 36.473270 (Lens L3 7)

39 -364 .89841 1.000000

40 246. • 94105 53. 921552

(Lens L 3 8)

41 * -323 .09677 5. 937773

42 778-36526 29. 012042 (Lens L 3 9)

43 -451 .33562 1.000 000 44 187.68025 25.248610 1.560000 (Lens L 3 0) 45 * 221.00795 16.525885

46 109.74451 70.000000 1.560000 (Lens L 3 1 1) 47 -777.78439 6.000000

(ゥゥ八面)

(Aspherical data)

1 9 faces

κ = 0. 0 0 0 0 0 0

C ₄ =-0.6 6 8 9 2 9 X 1 CT ⁸ C ₆ : 0.4 7 9 3 9 7 X ^10-13

C _s = — 0.6 7 3 1 3 2 X 10 -18 c 10 0.1 0 6 1 4 0 X 1 0 ²²

2 3 sides

κ = 0 0 0 0 0 0 0

C ₄ = one 0 1 3 2 9 84 X 1 0- 7 C - 0 - 1 7 7 7 8 9 X 1 0 - '3

C ₈ = 0 3 3 7448 X 1 0 -17 c 10 — 0.8 0 7 3 0 2 X 1 0 " ²²

2 7

0 0 0 0 0 0 0

C 0. 8 0 3 3 3 6 X 1 0- 7 C 0. 1 46 0 6 1 X 1 0- 11

C ₈ = 0. 1 1 4 8 2 0 X 1 0 10-0. 3 4 9 7 7 9 X 10 ²⁰

30 face

κ = 0 0 0 0 0 0 0

C ₄ = one 0 1 8 3 8 4 1 X 1 0- 6 C 6: 0. 7 3 1 6 7 1 X 1 0 - "

C ₈ = — 0 4 9 5 1 8 9 X 1 0 ” ¹⁵ C _l0 : 0.3 3 5 5 3 2 X 1 0— ¹⁹ 3 3 sides

κ = 0 0 0 0 0 0 0

C 1 0 5 1 343 3 X 1 0- ⁷ C f- — 0.3 6 9 5 4 3 X 1 0 ""

_{C R = - 0. 8 9 9} 1 5 5 X 1 0 - 16 C 10: - 0. 4 3 3 2 6 1 X 1 0- 20

3 8 faces

K = 0 0 0 0 0 0 0

_{C 4 = - 0 4 3 8} 0 7 8 X 1 0- 7 C 6: 0. 442 8 27 X 1 0 - 12

_{C 8 = - 0 5 6 2} 6 4 7 X 1 0 - 17 C 10: 0. 4 9 9 7 6 1 X 1 0 - 22

4 1 side

K = 0 0 0 0 0 0 0

C 0. 2 642 2 5 X 1 0- 7 C fi = 0. 2 2 4 9 6 5 X 1 0 -

_{C s = 0. 2 1 1 4} 7 8 X 1 0 "l6 C 10: 0. 2 3 5 5 3 8 X 1 0 - 2I

4 5

K = 0. 0 0 0 0 0 0

C 0 48 1 9 54 X 1 0- 7 C 6 0. 4 1 9 2 6 6 X 1 0- "

_{C s = 0 1 2 1 1} 5 2 X 1 0 - '5 C 10 0. 3 4' 4 8 1 1 X 1 0 - 20 FIGS. 8 and 9, the catadioptric optical system according to the second embodiment FIG. 4 is a view showing lateral aberration. In the aberration diagram, Y indicates the image height (mm). As is clear from the aberration diagrams, in the second embodiment, similarly to the first embodiment, the exposure light having a wavelength width of 15.7 nm ± 0.4 pm, that is, the center wavelength is 15.7 It can be seen that the chromatic aberration is favorably corrected for the F ₂ laser beam having a half width of 0.7 pm at 6 11111. In addition, spherical aberration, coma, astigmatism, and distortion (distortion) are good up to almost no aberration. It has been confirmed that it is well corrected and has excellent imaging performance.

As described above, in each embodiment described above, with respect to the center wavelength of 1 5 7. Of 6 nm F ₂ laser light 0. 8 4 while securing a large image-side NA of 5, the chromatic aberration on the wafer W It is possible to secure an image circle with a radius of 20 mm in which various aberrations such as are sufficiently corrected. Therefore, in each embodiment, it is possible to achieve a high resolution of 0.1 m or less while securing a sufficiently large rectangular effective exposure area of 22 mm × 5.5 mm. . Then, the pattern of the reticle R can be transferred with high precision to each exposure area having a size of, for example, 22 mm × 33 mm on the wafer W by scanning exposure. Further, in each of the above-described embodiments, a sufficiently long working distance on the wafer side of about 6 mm can be ensured. Also, in the first embodiment, the diameter of the two concave reflecting mirrors CM 1 and CM 3 is less than or equal to 335 mm, the effective diameter (diameter) of the two largest lenses is less than or equal to 335 mm, The effective diameter of most other lenses is less than 240 mm. On the other hand, in the second embodiment, the diameters of the two concave reflecting mirrors CM1 and CM3 are equal to or less than 3400 mm, and the effective diameter (diameter) of the two largest lenses is equal to or less than 3400 mm. The effective diameter of most other lenses is less than 230 mm. As described above, in each of the embodiments, the size of the optical system is reduced by suppressing an increase in the size of the concave reflecting mirror and the lens.

Furthermore, in each of the above embodiments, the number of lenses is very small (19 in the first embodiment, and 18 in the second embodiment), although the optical system is of the three-time imaging system. It has become. In the optical system using the F ₂ laser beam, because good good antireflection code Bok can not be obtained, it tends to cause the Oite light loss and the lens surface number of lenses is large. From this point of view, each of the above-described embodiments has a configuration in which the number of lenses is small and the loss of light quantity on the lens surface is suppressed.

Further, in the first embodiment, the object plane (reticle plane), the image plane (wafer plane), Is about 1.5 m, and in the second embodiment, the distance between the object plane and the image plane is about 1.3 m. Thus, in each embodiment, the distance between the object plane and the image plane is kept small, so that a high-performance and high-precision optical system can be realized, and the size of the apparatus can be further reduced. Can be. In each of the embodiments described above, the number of aspheric surfaces introduced is very small (eight in each embodiment).

In the above-described exposure apparatus, the reticle (mask) is illuminated by the illumination optical system (illumination step), and the transfer pattern formed on the reticle is scanned and exposed on the photosensitive substrate using the projection optical system (exposure step). Thereby, micro devices (semiconductor elements, imaging elements, liquid crystal display elements, thin-film magnetic heads, etc.) can be manufactured. The flow chart of FIG. 10 shows an example of a method for obtaining a semiconductor device as a micro device by forming a predetermined circuit pattern on a wafer or the like as a photosensitive substrate using the above-described exposure apparatus. It will be described with reference to FIG.

First, in step 301 of FIG. 10, a metal film is deposited on one lot of wafers. In the next step 302, a photoresist is applied to the metal film on the one-lot wafer. Thereafter, in step 303, the pattern image on the reticle is sequentially exposed and transferred to each shot area on the one-lot wafer via the projection optical system using the above-described exposure apparatus. Thereafter, in step 304, the photo resist on the wafer of the one lot is developed, and then in step 305, etching is performed on the wafer of the one lot using the resist pattern as a mask. As a result, a circuit pattern corresponding to the pattern on the reticle is formed in each shot area on each wafer. Thereafter, devices such as semiconductor elements are manufactured by forming a circuit pattern of the upper layer. According to the above-described semiconductor device manufacturing method, a semiconductor device having an extremely fine circuit pattern can be obtained with good throughput. Can be.

In the above-described exposure apparatus, 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 in FIG. In FIG. 11, in a pattern forming step 401, a so-called optical lithography step of transferring and exposing a reticle pattern to a photosensitive substrate (eg, a glass substrate coated with a resist) using the above-described exposure apparatus is performed. You. 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 processes such as a developing process, an etching process, and a reticle peeling process, so that a predetermined pattern is formed on the substrate, and the process proceeds to the next color fill forming process 402. I do.

Next, in the color filter forming process 402, a large number of sets of three dots corresponding to R (Red), G (Green), and B (Blue) are arranged in a matrix, or A color filter is formed in which a plurality of sets of three stripes of R, G, and B are arranged in a horizontal scanning line direction. Then, a cell assembling step 403 is executed after the color-fill-filling-illustration forming step 402. In the cell assembling step 403, the liquid crystal is formed by using 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. Assemble the panel (liquid crystal cell). In the cell assembling step 403, for example, 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. To manufacture liquid crystal panels (liquid crystal cells).

Then, in the module assembling step 404, each of the electric circuits and backlights, etc., that perform the display operation of the assembled liquid crystal panel (liquid crystal cell) Attach components to complete the liquid crystal display device. 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 good throughput.

In the above-described exposure apparatus, light having a wavelength of 157.611111 is supplied? _{Although two} lasers are used, the wavelength is not limited to this.

4 8 nm of K r F excimer laser or a wavelength 1 9 3 nm of the supplied A r F excimer laser or a wavelength 1 2 6 nm in the use of such A r _2, single THE supplies optical light supplies light Can also.

In the above exposure apparatus, the present invention is applied to the projection optical system of the scanning exposure type exposure apparatus. However, the present invention is not limited to this, and the present invention is applied to the projection optical system of the batch exposure type exposure apparatus. The present invention can be applied to general imaging optical systems other than the projection optical system of the exposure apparatus.

As described above, the catadioptric optical system of the present invention has a simple configuration in which the distance between the object plane and the image plane is small and the number of lenses is small, so that a high-performance optical system in which the loss of light quantity on the lens plane is successfully suppressed A high-precision optical system can be realized, for example, a high resolution of 0.1 xm or less can be achieved by using light in a vacuum ultraviolet wavelength region having a wavelength of 180 nm or less. In addition, for example, it is necessary to secure a position where an effective aperture stop should be installed, to secure a sufficiently long single king distance, and to reduce the size of the concave reflecting mirror to reduce the size of the optical system. it can.

Further, by applying the catadioptric optical system of the present invention to a projection optical system of an exposure apparatus, for example, using exposure light having a wavelength of 180 nm or less, a high resolution of 0.1 ^ am or less can be obtained. Projection exposure can be performed. Further, by using an exposure apparatus equipped with the catadioptric optical system of the present invention as a projection optical system and performing good projection exposure at a high resolution of, for example, 0.1 / ^ m or less, a high-precision micro Devices can be manufactured.

Claims

The scope of the claims

1-a first imaging optical system having at least one concave reflecting mirror and at least one flat reflecting mirror, and forming a first intermediate image of the first surface based on light from the first surface; ,

A refraction-type third imaging optical system for forming a final image of the first surface on the second surface based on light passing through the second imaging optical system. Catadioptric optics.

2. All the optical members except the plane reflecting mirror of the first imaging optical system and all the optical members except the plane reflecting mirror of the second imaging optical system are a single linearly extending single second reflecting optical system. 1 placed along the optical axis,

All the optical members of the third imaging optical system are arranged along a single second optical axis linearly extending so as to be orthogonal to the first optical axis,

The light from the first surface sequentially forms the first intermediate image through one plane reflecting mirror and one concave reflecting mirror in the first imaging optical system,

The light passing through the first imaging optical system forms the second intermediate image through one planar reflecting mirror and one concave reflecting mirror of the second imaging optical system in order. 2. The catadioptric optical system according to claim 1, wherein:

3. The catadioptric optical system according to claim 2, wherein the first imaging optical system has at least one negative lens component disposed immediately before the concave reflecting mirror.

4. The catadioptric optical system according to claim 2, wherein the second imaging optical system has at least one negative lens component disposed immediately before the concave reflecting mirror.

5. The field lens according to any one of claims 1 to 3, wherein a field lens is disposed in an optical path between the first imaging optical system and the second imaging optical system. Catadioptric optics.

6. The catadioptric optical system according to claim 4, wherein a field lens is disposed in an optical path between the first imaging optical system and the second imaging optical system.

7. At least one of the field lenses disposed in the optical path between the first imaging optical system and the second imaging optical system is a lens of the first imaging optical system. The catadioptric refraction according to claim 5, wherein the catadioptric refraction according to claim 5, characterized in that it has a partially cut-out shape so as to pass only the light reflected from the concave reflector without passing the light incident on the concave reflector. Optical system. 8At least one of the field lenses disposed in an optical path between the first imaging optical system and the second imaging optical system is a lens of the first imaging optical system. The catadioptric optical element according to claim 6, wherein the catadioptric optical element has a partially cut-out shape so as to allow only the reflected light from the concave reflecting mirror to pass without passing the incident light to the concave reflecting mirror. system.

9 · An optical path between the first imaging optical system and the second imaging optical system At least one of the placed field lenses is formed so as to pass both light incident on the concave reflecting mirror of the first imaging optical system and reflected light from the concave reflecting mirror. 6. The catadioptric optical system according to claim 5, wherein:

10. At least one of the field lenses disposed in the optical path between the first imaging optical system and the second imaging optical system is the concave surface of the first imaging optical system. 7. The catadioptric optical system according to claim 6, wherein the catadioptric optical system is formed so as to pass both light incident on a reflecting mirror and light reflected from the concave reflecting mirror.

11. At least one of the field lenses disposed in an optical path between the first imaging optical system and the second imaging optical system includes: 8. The catadioptric optical system according to claim 7, wherein the catadioptric optical system is formed so as to pass both the light incident on the concave reflecting mirror and the light reflected from the concave reflecting mirror.

12. At least one of the field lenses disposed in the optical path between the first imaging optical system and the second imaging optical system is the first imaging optical system. 9. The catadioptric optical system according to claim 8, wherein the catadioptric optical system is formed so as to pass both light incident on the concave reflecting mirror and light reflected from the concave reflecting mirror.

13. A field lens is disposed in an optical path between the second imaging optical system and the third imaging optical system, wherein the field lens is disposed. Catadioptric system.

14. The catadioptric optical system according to claim 4, wherein a field lens is disposed in an optical path between the second imaging optical system and the third imaging optical system. 15. The catadioptric optical system according to claim 5, wherein a field lens is disposed in an optical path between the second imaging optical system and the third imaging optical system.

16. The catadioptric optical system according to claim 6, wherein a field lens is disposed in an optical path between the second imaging optical system and the third imaging optical system.

17. The catadioptric optical system according to claim 7, wherein a field lens is disposed in an optical path between the second imaging optical system and the third imaging optical system.

18. The catadioptric optical system according to claim 8, wherein a field lens is disposed in an optical path between the second imaging optical system and the third imaging optical system.

19. The catadioptric optical system according to claim 9, wherein a field lens is disposed in an optical path between the second imaging optical system and the third imaging optical system. 20. The catadioptric optical system according to claim 10, wherein a field lens is disposed in an optical path between the second imaging optical system and the third imaging optical system.

21. The catadioptric optical system according to claim 11, wherein a field lens is arranged in an optical path between the second imaging optical system and the third imaging optical system.

22. The catadioptric optical system according to claim 12, wherein a field lens is disposed in an optical path between the second imaging optical system and the third imaging optical system. 23. An illumination system for illuminating the mask set on the first surface, and an image of a pattern formed on the mask on a photosensitive substrate set on the second surface. An exposure apparatus comprising: the reflection refraction optical system according to any one of 1 to 3. 24. An illumination system for illuminating the mask set on the first surface, and an image of a pattern formed on the mask on a photosensitive substrate set on the second surface. An exposure apparatus comprising: the catadioptric optical system according to 4. 25. An illumination system for illuminating the mask set on the first surface, and an image of a pattern formed on the mask on a photosensitive substrate set on the second surface. An exposure apparatus comprising: the catadioptric optical system according to 5. 26. An illumination system for illuminating the mask set on the first surface, and an image of a pattern formed on the mask on a photosensitive substrate set on the second surface. And the catadioptric optical system according to 6. An exposure apparatus, comprising:

27. An illumination system for illuminating the mask set on the first surface, and an image of a pattern formed on the mask on a photosensitive substrate set on the second surface. An exposure apparatus comprising: the catadioptric optical system according to 7.

28. An illumination system for illuminating the mask set on the first surface, and an image of a pattern formed on the mask on a photosensitive substrate set on the second surface. 9. An exposure apparatus, comprising: the catadioptric optical system according to 8.

29. An illumination system for illuminating the mask set on the first surface, and an image of a pattern formed on the mask on a photosensitive substrate set on the second surface. An exposure apparatus comprising the catadioptric optical system according to claim 9.

30. An illumination system for illuminating the mask set on the first surface, and an image of a pattern formed on the mask on a photosensitive substrate set on the second surface. An exposure apparatus, comprising: the catadioptric optical system according to 10.

31. An illumination system for illuminating the mask set on the first surface, and an image of a pattern formed on the mask on a photosensitive substrate set on the second surface. An exposure apparatus comprising the catadioptric optical system according to item 11.

32. An illumination system for illuminating the mask set on the first surface, and an image of a pattern formed on the mask on a photosensitive substrate set on the second surface. An exposure apparatus comprising the catadioptric optical system according to item 12.

33. An illumination system for illuminating the mask set on the first surface, and for forming an image of a pattern formed on the mask on a photosensitive substrate set on the second surface. An exposure apparatus comprising the catadioptric optical system according to item 13.

34. An illumination system for illuminating the mask set on the first surface, and an image of a pattern formed on the mask on a photosensitive substrate set on the second surface. An exposure apparatus comprising the catadioptric optical system according to item 14.

35. An illumination system for illuminating the mask set on the first surface, and an image of a pattern formed on the mask on a photosensitive substrate set on the second surface. An exposure apparatus comprising the catadioptric optical system according to item 15.

36. An illumination system for illuminating the mask set on the first surface, and an image of a pattern formed on the mask on a photosensitive substrate set on the second surface. An exposure apparatus comprising the catadioptric optical system according to item 16.

37. An illumination system for illuminating the mask set on the first surface, and an image of a pattern formed on the mask is exposed to light on the second surface. An exposure apparatus comprising: the catadioptric optical system according to claim 17 for forming on a functional substrate.

38. An illumination system for illuminating the mask set on the first surface, and for forming an image of a pattern formed on the mask on a photosensitive substrate set on the second surface. An exposure apparatus comprising the catadioptric optical system according to item 18.

39. An illumination system for illuminating the mask set on the first surface, and an image of a pattern formed on the mask on a photosensitive substrate set on the second surface. An exposure apparatus comprising the catadioptric optical system according to item 19.

40. An illumination system for illuminating a mask set on the first surface, and an image of a pattern formed on the mask on a photosensitive substrate set on the second surface. 20. An exposure apparatus comprising the catadioptric optical system according to 20.

41. An illumination system for illuminating the mask set on the first surface, and an image of a pattern formed on the mask on a photosensitive substrate set on the second surface. An exposure apparatus comprising the catadioptric optical system according to item 21.

42. An illumination system for illuminating the mask set on the first surface, and an image of a pattern formed on the mask on a photosensitive substrate set on the second surface. 22. An exposure apparatus comprising the catadioptric optical system described in 22 above.