JP5353408B2 - Illumination optical system, exposure apparatus, and device manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an illumination optical system capable of stably exhibiting necessary functions for a necessary period of time. <P>SOLUTION: The illumination optical system which illuminates a surface to be irradiated with light from a light source includes: first and second spatial optical modulators which spatially and optically modulate and then project incident light; first and second deflection surfaces which deflect first luminous flux (L10) passed through the first spatial optical modulator and second luminous flux (L20) passed through the second spatial optical modulator to following optical systems, respectively; and luminous flux shift members (5: 5a, 5b) which are disposed in optical paths between the first deflection surface and second deflection surface, and the following optical systems, and shift one of the first luminous flux and second luminous flux in a direction (Z direction) crossing an optical axis so as to put the first luminous flux and second luminous flux closer to each other. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to an illumination optical system, an exposure apparatus, and a device manufacturing method. More specifically, the present invention relates to an illumination optical system suitable for an exposure apparatus for manufacturing devices such as a semiconductor element, an image sensor, a liquid crystal display element, and a thin film magnetic head in a lithography process.

  In a typical exposure apparatus of this type, a light beam emitted from a light source is passed through a fly-eye lens as an optical integrator, and a secondary light source (generally an illumination pupil) as a substantial surface light source composed of a number of light sources. A predetermined light intensity distribution). Hereinafter, the light intensity distribution in the illumination pupil is referred to as “illumination pupil luminance distribution”. The illumination pupil is a position where the illumination surface becomes the Fourier transform plane of the illumination pupil by the action of the optical system between the illumination pupil and the illumination surface (a mask or a wafer in the case of an exposure apparatus). Defined.

  The light beam from the secondary light source is condensed by the condenser lens and then illuminates the mask on which a predetermined pattern is formed in a superimposed manner. The light transmitted through the mask forms an image on the wafer via the projection optical system, and the mask pattern is projected and exposed (transferred) onto the wafer. The pattern formed on the mask is highly integrated, and it is indispensable to obtain a uniform illumination distribution on the wafer in order to accurately transfer the fine pattern onto the wafer.

  Conventionally, there has been proposed an illumination optical system capable of continuously changing the illumination pupil luminance distribution (and thus the illumination condition) without using a zoom optical system (see Patent Document 1). In the illumination optical system disclosed in Patent Document 1, an incident light beam is generated using a movable multi-mirror configured by a large number of minute mirror elements that are arranged in an array and whose tilt angle and tilt direction are individually driven and controlled. By dividing and deflecting into minute units for each reflecting surface, the cross section of the light beam is converted into a desired shape or a desired size, and thus a desired illumination pupil luminance distribution is realized.

JP 2002-353105 A

  In the illumination optical system described in Patent Document 1, since a movable multi-mirror is used, the degree of freedom with respect to changing the shape and size of the illumination pupil luminance distribution is high. However, since the spatial light modulation unit used in this illumination optical system to form the illumination pupil luminance distribution uses a movable multi-mirror as a single spatial light modulator, the light incident on the reflection surface of the mirror element The energy per unit area is relatively large. As a result, the reflectivity of the mirror element tends to decrease with time due to light irradiation, and as a result, it becomes difficult for the illumination optical system to stably perform a required function over a required period.

  On the other hand, if the cross section of the incident light beam to the spatial light modulation unit is made large in order to keep the energy per unit area of light incident on the reflecting surface of the mirror element small, the reflection occupied by many mirror elements arranged two-dimensionally The total area of the region increases, and the spatial light modulator increases in size. Increasing the size of the spatial light modulator leads to an increase in the size of optical systems (lenses, prisms, mirrors, etc.) on the incident side and the exit side of the spatial light modulator, which in turn increases the size and cost of the spatial light modulation unit. End up.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide an illumination optical system that can stably exhibit a required function over a required period. In addition, the present invention provides an exposure apparatus capable of stably performing good exposure over a required period using an illumination optical system capable of stably exhibiting a required function over a required period. The purpose is to do.

In order to solve the above problems, in the first embodiment of the present invention, in the illumination optical system that illuminates the illuminated surface based on the light from the light source,
A first spatial light modulator that emits the incident light after applying spatial light modulation;
A second spatial light modulator that emits light after applying spatial light modulation to the incident light;
A first deflecting surface for deflecting the first light flux that has passed through the first spatial light modulator toward a subsequent optical system;
A second deflecting surface for deflecting the second light flux that has passed through the second spatial light modulator toward the subsequent optical system;
The first light beam and the second light beam are disposed in an optical path between the first deflection surface and the second deflection surface and the subsequent optical system so as to bring the first light beam and the second light beam closer to each other. An illumination optical system is provided that includes a light beam shift member that shifts at least one of the two light beams in a direction crossing the optical axis.

  According to a second aspect of the present invention, there is provided an exposure apparatus comprising the illumination optical system according to the first aspect for illuminating a predetermined pattern, and exposing the predetermined pattern onto a photosensitive substrate.

In the third embodiment of the present invention, using the exposure apparatus of the second embodiment, an exposure step of exposing the predetermined pattern to the photosensitive substrate;
Developing the photosensitive substrate to which the predetermined pattern is transferred, and forming a mask layer having a shape corresponding to the predetermined pattern on the surface of the photosensitive substrate;
And a processing step of processing the surface of the photosensitive substrate through the mask layer.

  In the present invention, since the spatial light modulation unit includes a pair of spatial light modulators, the energy per unit area of light incident on the spatial light modulator is compared with the case where the spatial light modulator is used alone. Can be kept small. Specifically, when a pair of reflective spatial light modulators having a plurality of mirror elements is used, the energy per unit area of light incident on the reflecting surface of the mirror elements can be kept small. As a result, in the spatial light modulation unit, the reflectance of the mirror element is unlikely to decrease even when light irradiation is performed over a long period of time, and a required function can be stably exhibited over a required period.

  Therefore, in the illumination optical system of the present invention, the spatial light modulation unit that stably exhibits the required function is used to realize a variety of illumination conditions for the shape and size of the illumination pupil luminance distribution, and the required This function can be stably exhibited over a required period. In the exposure apparatus of the present invention, an illumination optical system that realizes a variety of illumination conditions and stably exhibits a required function over a required period, according to the characteristics of a pattern to be transferred. Good exposure can be stably performed over a required period under appropriate illumination conditions realized, and thus a good device can be manufactured.

  In the illumination optical system of the present invention, at least one of the first light flux that has passed through the first spatial light modulator and the second light flux that has passed through the second spatial light modulator is caused to act on the optical axis by the action of the light flux shifting member. The first light flux and the second light flux can be brought close to each other at a predetermined position in the optical path. As a result, the effective diameter of the subsequent optical system can be kept small, and the illumination optical system can be downsized.

It is a figure which shows schematically the structure of the exposure apparatus concerning embodiment of this invention. It is a figure which shows schematically the internal structure of the spatial light modulation unit concerning this embodiment. It is a perspective view which shows roughly the structure of a cylindrical micro fly's eye lens. It is a figure which shows schematically the principal part structure of the spatial light modulation unit of FIG. FIG. 5 is a partial perspective view of the spatial light modulator of FIG. 4. It is a figure which shows typically the light intensity distribution of 4 pole shape formed in the pupil plane of an afocal lens in this embodiment. When the light beam shift member is not provided, the first light beam that has passed through the first spatial light modulator and the second light beam that has passed through the second spatial light modulator pass through the position of the predetermined surface with a relatively large distance. FIG. FIG. 6 is a diagram for explaining the reason why the first light flux that has passed through the first spatial light modulator and the second light flux that has passed through the second spatial light modulator are separated by a relatively large distance at a predetermined surface position when no light flux shifting member is provided. is there. It is a figure which shows schematically the structure of the light beam shift member concerning this embodiment. It is a figure which shows schematically the structure of the light beam shift member concerning a modification. It is a flowchart which shows the manufacturing process of a semiconductor device. It is a flowchart which shows the manufacturing process of liquid crystal devices, such as a liquid crystal display element.

  Embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a drawing schematically showing a configuration of an exposure apparatus according to an embodiment of the present invention. FIG. 2 is a diagram schematically showing an internal configuration of the spatial light modulation unit according to the present embodiment. In FIG. 1, the Z-axis is along the normal direction of the transfer surface (exposure surface) of the wafer W, which is a photosensitive substrate, and the Y-axis is in the direction parallel to the paper surface of FIG. In the W transfer surface, the X axis is set in a direction perpendicular to the paper surface of FIG.

  Referring to FIG. 1, in the exposure apparatus of the present embodiment, exposure light (illumination light) is supplied from a light source 1. As the light source 1, for example, an ArF excimer laser light source that supplies light with a wavelength of 193 nm, a KrF excimer laser light source that supplies light with a wavelength of 248 nm, or the like can be used. The light emitted from the light source 1 is expanded into a light beam having a required cross-sectional shape by the shaping optical system 2 and then enters the spatial light modulation unit 3. As shown in FIG. 2, the spatial light modulation unit 3 includes a pair of spatial light modulators 3a and 3b and a pair of triangular prisms 3c and 3d. The specific configuration and operation of the spatial light modulation unit 3 will be described later.

  Referring again to FIG. 1, the light emitted from the spatial light modulation unit 3 enters the afocal lens 4. The afocal lens 4 is an afocal system (non-focal optical system) including a front lens group 4 a and a rear lens group 4 b, and the focal position of the front lens group 4 a and the first space in the spatial light modulation unit 3. The position of the optical modulator 3a and the position of the second spatial light modulator 3b are substantially matched, and the focal position of the rear lens group 4b and the position of the predetermined plane IP indicated by a broken line in the figure are set to be substantially matched. Has been. The light beam shift member 5 is disposed at a position immediately before the predetermined plane IP, that is, at a position optically conjugate with the first spatial light modulator 3a and the second spatial light modulator 3b. A specific configuration and operation of the light beam shift member 5 will be described later.

  The light that has passed through the first spatial light modulator 3a is, for example, two circles spaced apart in the Z direction around the optical axis AX on the pupil plane of the afocal lens 4 (position indicated by reference numeral 4c in FIG. 2). After forming a Z-direction dipolar light intensity distribution composed of a shape light intensity distribution, the light is emitted from the afocal lens 4 with a dipolar angular distribution. On the other hand, the light that has passed through the second spatial light modulator 3b is, on the pupil plane of the afocal lens 4, for example, an X direction composed of two circular light intensity distributions spaced apart in the X direction about the optical axis AX. After forming a dipolar light intensity distribution, the light is emitted from the afocal lens 4 with a dipolar angular distribution.

  A conical axicon system 6 is arranged at the position of the pupil surface of the afocal lens 4 or a position in the vicinity thereof. The configuration and operation of the conical axicon system 6 will be described later. The light beam that has passed through the afocal lens 4 passes through a zoom lens 7 for varying a σ value (σ value = mask-side numerical aperture of the illumination optical system / mask-side numerical aperture of the projection optical system), and a cylindrical micro fly's eye lens 8. Is incident on.

  As shown in FIG. 3, the cylindrical micro fly's eye lens 8 includes a first fly eye member 8a disposed on the light source side and a second fly eye member 8b disposed on the mask side. On the light source side surface of the first fly eye member 8a and the light source side surface of the second fly eye member 8b, cylindrical lens groups 8aa and 8ba arranged side by side in the X direction are formed at a pitch p1, respectively. Cylindrical lens groups 8ab and 8bb arranged side by side in the Z direction on the mask side surface of the first fly eye member 8a and the mask side surface of the second fly eye member 8b, respectively, with a pitch p2 (p2> p1). Is formed.

  Focusing on the refraction action in the X direction of the cylindrical micro fly's eye lens 8 (that is, the refraction action in the XY plane), the parallel luminous flux incident along the optical axis AX is formed on the light source side of the first fly eye member 8a. The wavefront is divided by the lens group 8aa along the X direction at the pitch p1, and after receiving the light condensing action on the refracting surface, the corresponding one of the cylindrical lens groups 8ba formed on the light source side of the second fly's eye member 8b. The light is focused on the refracting surface of the cylindrical lens and focused on the rear focal plane of the cylindrical micro fly's eye lens 8.

  Focusing on the refractive action in the Z direction of the cylindrical micro fly's eye lens 8 (that is, the refractive action in the YZ plane), the parallel light beam incident along the optical axis AX is formed on the cylindrical side of the first fly's eye member 8a on the mask side. After the wavefront is divided at the pitch p2 along the Z direction by the lens group 8ab, and after receiving the light condensing action on the refracting surface, the corresponding one of the cylindrical lens groups 8bb formed on the mask side of the second fly's eye member 8b. The light is focused on the refracting surface of the cylindrical lens and focused on the rear focal plane of the cylindrical micro fly's eye lens 8.

  As described above, the cylindrical micro fly's eye lens 8 is constituted by the first fly eye member 8a and the second fly eye member 8b in which the cylindrical lens groups are arranged on both side surfaces, but the size of p1 is set in the X direction. It has an optical function similar to that of a micro fly's eye lens in which a large number of rectangular minute refracting surfaces having a size of p2 in the Z direction are integrally formed vertically and horizontally. In the cylindrical micro fly's eye lens 8, a change in distortion due to variations in the surface shape of the micro-refractive surface is suppressed to be small, and for example, manufacturing errors of a large number of micro-refractive surfaces integrally formed by etching process give the illuminance distribution. The influence can be kept small. Examples of such cylindrical micro fly's eye lenses include US Pat. Nos. 6,913,373 and 7,379,160, US Patent Publication Nos. 2008/0074631, 2008/0225256 and 2008/0225257. And International Patent Publication No. WO2008 / 126570 can be referred to.

  The position of the predetermined plane IP is disposed in the vicinity of the front focal position of the zoom lens 7, and the incident surface of the cylindrical micro fly's eye lens 8 is disposed in the vicinity of the rear focal position of the zoom lens 7. In other words, the zoom lens 7 arranges the predetermined plane IP and the incident surface of the cylindrical micro fly's eye lens 8 substantially in a Fourier transform relationship, and consequently the pupil plane of the afocal lens 4 and the cylindrical micro fly's eye lens 8. The incident surface is optically substantially conjugate.

  Accordingly, on the incident surface of the cylindrical micro fly's eye lens 8, as with the pupil surface of the afocal lens 4, for example, two circular light intensity distributions and light with an interval in the Z direction centered on the optical axis AX. A quadrupole illumination field is formed which consists of two circular light intensity distributions spaced apart in the X direction about the axis AX. The overall shape of this quadrupole illumination field changes in a similar manner depending on the focal length of the zoom lens 7. The rectangular micro-refractive surface as a wavefront division unit in the cylindrical micro fly's eye lens 8 has a rectangular shape similar to the shape of the illumination field to be formed on the mask M (and thus the shape of the exposure region to be formed on the wafer W). It is.

  The light beam incident on the cylindrical micro fly's eye lens 8 is two-dimensionally divided, and has two light intensity distributions on the rear focal plane or in the vicinity thereof (and thus the illumination pupil) having substantially the same light intensity distribution as the illumination field formed by the incident light beam. The next light source, that is, two circular substantial surface light sources spaced in the Z direction around the optical axis AX and two circular substantial surfaces spaced in the X direction around the optical axis AX A quadrupole secondary light source (a quadrupole illumination pupil luminance distribution) composed of a light source is formed. A light beam from a secondary light source formed on the rear focal plane of the cylindrical micro fly's eye lens 8 or in the vicinity thereof enters an aperture stop 9 disposed in the vicinity thereof.

  The aperture stop 9 has a quadrupole opening (light transmission portion) corresponding to a quadrupole secondary light source formed at or near the rear focal plane of the cylindrical micro fly's eye lens 8. The aperture stop 9 is configured to be detachable with respect to the illumination optical path, and is configured to be switchable between a plurality of aperture stops having openings having different sizes and shapes. As an aperture stop switching method, for example, a well-known turret method or slide method can be used. The aperture stop 9 is disposed at a position that is optically conjugate with an entrance pupil plane of the projection optical system PL described later, and defines a range that contributes to illumination of the secondary light source.

  The light from the secondary light source limited by the aperture stop 9 illuminates the mask blind 11 in a superimposed manner via the condenser optical system 10. Thus, a rectangular illumination field corresponding to the shape and focal length of the rectangular micro-refractive surface which is the wavefront division unit of the cylindrical micro fly's eye lens 8 is formed on the mask blind 11 as the illumination field stop. The light beam that has passed through the rectangular opening (light transmitting portion) of the mask blind 11 receives the light condensing action of the imaging optical system 12 and then illuminates the mask M on which a predetermined pattern is formed in a superimposed manner. That is, the imaging optical system 12 forms an image of the rectangular opening of the mask blind 11 on the mask M.

  The light beam transmitted through the mask M held on the mask stage MS forms an image of a mask pattern on the wafer (photosensitive substrate) W held on the wafer stage WS via the projection optical system PL. In this way, batch exposure or scan exposure is performed while the wafer stage WS is two-dimensionally driven and controlled in a plane (XY plane) orthogonal to the optical axis AX of the projection optical system PL, and thus the wafer W is two-dimensionally driven and controlled. As a result, the pattern of the mask M is sequentially exposed in each exposure region of the wafer W.

  The conical axicon system 6 includes, in order from the light source side, a first prism member 6a having a flat surface facing the light source side and a concave conical refractive surface facing the mask side, and a convex conical shape facing the plane toward the mask side and the light source side. And a second prism member 6b facing the refractive surface. The concave conical refracting surface of the first prism member 6a and the convex conical refracting surface of the second prism member 6b are complementarily formed so as to be in contact with each other. Further, at least one of the first prism member 6a and the second prism member 6b is configured to be movable along the optical axis AX, and the concave conical refracting surface of the first prism member 6a and the second prism member 6b. The distance from the convex conical refracting surface is variable. Hereinafter, in order to facilitate understanding, the operation of the conical axicon system 6 and the operation of the zoom lens 7 will be described focusing on a quadrupolar or annular secondary light source.

  In a state where the concave conical refracting surface of the first prism member 6a and the convex conical refracting surface of the second prism member 6b are in contact with each other, the conical axicon system 6 functions as a plane parallel plate and is formed as a four-pole. There is no effect on the secondary light source in the form of a ring or ring. However, when the concave conical refracting surface of the first prism member 6a and the convex conical refracting surface of the second prism member 6b are separated from each other, the width of the quadrupolar or annular secondary light source (the quadrupolar secondary light source). 1/2 of the difference between the diameter (outer diameter) of the circle circumscribing the light source and the diameter (inner diameter) of the inscribed circle; 1/2 of the difference between the outer diameter and inner diameter of the annular secondary light source The outer diameter (inner diameter) of the quadrupole or ring-shaped secondary light source changes while maintaining. That is, the annular ratio (inner diameter / outer diameter) and size (outer diameter) of the quadrupolar or annular secondary light source change.

  The zoom lens 7 has a function of enlarging or reducing the overall shape of the quadrupolar or annular secondary light source in a similar (isotropic) manner. For example, by expanding the focal length of the zoom lens 7 from a minimum value to a predetermined value, the overall shape of the quadrupolar or annular secondary light source is enlarged similarly. In other words, the width and size (outer diameter) of the quadrupole or ring-shaped secondary light source are both changed by the action of the zoom lens 7 without changing. As described above, the annular ratio and the size (outer diameter) of the quadrupolar or annular secondary light source can be controlled by the action of the conical axicon system 6 and the zoom lens 7.

  In the spatial light modulation unit 3, as shown in FIG. 2, a light beam from the light source 1 via the shaping optical system 2, for example, a substantially parallel light beam having a rectangular cross section elongated in the X direction around the optical axis AX, The light enters the prism 3c. The triangular prism 3c is formed of an optical material such as fluorite, for example, has a triangular cross section along the YZ plane, and has a triangular prism shape extending in the X direction as a whole. Further, in the triangular cross section of the triangular prism 3c, the apex angle toward the light incident side (left side in FIG. 2) is an acute angle, and the ridge line corresponding to the apex angle extends in the X direction through the optical axis AX. Yes.

  The side surface 3ca of the triangular prism 3c functions as a deflection surface that reflects incident light toward the main body 3aa of the first spatial light modulator 3a, and the side surface 3cb transmits incident light to the main body 3ba of the second spatial light modulator 3b. It functions as a deflecting surface that reflects toward it. The triangular prism 3c divides incident light into two lights along the ridge line between the deflection surfaces 3ca and 3cb. In other words, the triangular prism 3c includes a deflection surface 3ca that deflects incident light toward the first spatial light modulator 3a, and a deflection surface 3cb that deflects incident light toward the second spatial light modulator 3b. And a split light guide member that divides incident light into first light and second light along a ridge line between the deflection surfaces 3ca and 3cb. Here, a reflection film is formed on the surfaces of the deflection surfaces 3ca and 3cb. As the reflective film, a metal film such as aluminum or a dielectric multilayer film can be used.

  The first light out of the two lights divided by the triangular prism 3c is reflected by the side surface 3da of the triangular prism 3d through the first spatial light modulator 3a and emitted from the spatial light modulation unit 3. It reaches the pupil plane 4c of the afocal lens 4 via the front lens group 4a. On the other hand, the second light of the two lights divided by the triangular prism 3c is reflected by the side surface 3db of the triangular prism 3d through the second spatial light modulator 3b and is emitted from the spatial light modulation unit 3. Then, it reaches the pupil plane 4c via the front lens group 4a. The front lens group 4a of the afocal lens 4 superimposes the first light beam via the first spatial light modulator 3a and the second light beam via the second spatial light modulator 3b on the pupil plane 4c.

  The triangular prism 3d is formed of an optical material such as fluorite, for example, similarly to the triangular prism 3c, and has a triangular column shape extending in the X direction as a whole with a triangular cross section along the YZ plane. Further, in the triangular cross section of the triangular prism 3d, the apex angle toward the light exit side (right side in FIG. 2) is an acute angle, and the ridge line corresponding to this apex angle extends in the X direction through the optical axis AX. Yes. The side surface 3da of the triangular prism 3d functions as a deflecting surface that reflects the first light beam that has passed through the first spatial light modulator 3a toward the subsequent front lens group 4a, and the side surface 3db has a second surface that passes through the second spatial light modulator 3b. It functions as a deflection surface that reflects the two light beams toward the subsequent front lens group 4a. Here, a reflective film is formed on the surfaces of the deflection surfaces 3da and 3db. As the reflective film, a metal film such as aluminum or a dielectric multilayer film can be used.

  The optical material forming the triangular prisms 3c and 3d is not limited to fluorite, and may be quartz glass or other optical material according to the wavelength of light supplied from the light source 1 or the like. Also good. The triangular prisms 3c and 3d are not limited to optical materials, and may be formed of a metal material such as aluminum or stainless steel. Note that the triangular prisms 3c and 3d may be formed of silicon carbide (SiC). FIG. 2 shows an example in which the triangular prisms 3c and 3d are formed as separate optical blocks. However, the triangular prisms 3c and 3d may be integrally formed with one optical block.

  Hereinafter, in order to facilitate understanding of the description, a first optical unit including a deflection surface 3ca, a first spatial light modulator 3a, and a deflection surface 3da, a deflection surface 3cb, a second spatial light modulator 3b, and a deflection surface. The second optical unit composed of 3 db has the same configuration as each other and is arranged symmetrically with respect to a plane including the optical axis AX and parallel to the XY plane. That is, the triangular prism 3c has a pair of side surfaces 3ca and 3cb that are symmetric with respect to a plane parallel to the XY plane including the optical axis AX, and the triangular prism 3d is symmetric with respect to a plane including the optical axis AX and parallel to the XY plane. It shall have a pair of side surfaces 3da and 3db.

  Accordingly, the description of the second optical unit (3cb, 3b, 3db) overlapping with the first optical unit (3ca, 3a, 3da) is omitted, and the space is focused on the first optical unit (3ca, 3a, 3da). A specific configuration and operation of the light modulation unit 3 will be described. As shown in FIG. 4, the spatial light modulator 3a in the first optical unit (3ca, 3a, 3da) includes a main body 3aa having a plurality of mirror elements SE arranged two-dimensionally, and a plurality of mirror elements SE. And a drive unit 3ab for individually controlling and driving the posture.

  The deflection surface (side surface) 3ca of the triangular prism 3c reflects incident light toward the spatial light modulator 3a, and the spatial light modulator 3a reflects light incident through the deflection surface 3ca. The deflection surface (side surface) 3da of the triangular prism 3d reflects the light incident through the spatial light modulator 3a and guides it to the front lens group 4a of the afocal lens 4. In FIG. 4, in order to facilitate understanding of the description, the optical path of the first light beam is developed linearly on the rear side of the front lens group 4 a. Further, in FIG. 4, the main bodies of the triangular prisms 3c and 3d are not shown, and only the deflection surfaces 3ca and 3da are shown.

  The spatial light modulator 3a emits the light incident through the deflecting surface 3ca with spatial modulation corresponding to the incident position. As shown in FIG. 5, the main body 3aa of the spatial light modulator 3a includes a plurality of minute mirror elements (optical elements) SE arranged two-dimensionally. For ease of explanation and illustration, FIG. 4 and FIG. 5 show a configuration example in which the spatial light modulator 3a includes 4 × 4 = 16 mirror elements SE. Are provided with a number of mirror elements SE.

  Referring to FIG. 4, among the light beams incident on the deflecting surface 3 ca of the triangular prism 3 c along the direction parallel to the optical axis AX, the light beam L1 is applied to the mirror element SEa of the plurality of mirror elements SE, and the light beam L2 is The light is incident on a mirror element SEb different from the mirror element SEa. Similarly, the light beam L3 is incident on a mirror element SEc different from the mirror elements SEa and SEb, and the light beam L4 is incident on a mirror element SEd different from the mirror elements SEa to SEc. The mirror elements SEa to SEd give spatial modulations set according to their positions to the lights L1 to L4.

  In the spatial light modulator 3a, in the reference state (hereinafter referred to as “reference state”) in which the reflection surfaces of all the mirror elements SE are set parallel to the XY plane, the deflection surfaces along the direction parallel to the optical axis AX. The light beam incident on 3ca passes through the spatial light modulator 3a and is then reflected by the deflecting surface 3da in a direction parallel to the optical axis AX. In other words, the traveling direction of the light emitted from the deflection surface 3da in the reference state and the traveling direction of the light emitted from the deflection surface 3db in the reference state are parallel to the optical axis AX. With this configuration, the optical path is coaxial (in some cases parallel) between the upstream and downstream of the spatial light modulation unit 3, so that, for example, a conventional illumination optical system and optical system using a diffractive optical element to form an illumination pupil luminance distribution. The system can be shared.

  The surface on which the plurality of mirror elements SE of the spatial light modulator 3a are arranged is positioned at or near the focal position of the front lens group 4a of the afocal lens 4. Therefore, the light reflected by the plurality of mirror elements SEa to SEd of the spatial light modulator 3a and given a predetermined angular distribution forms predetermined light intensity distributions SP1 to SP4 on the pupil plane 4c of the afocal lens 4. . That is, the front lens group 4a has an angle that the plurality of mirror elements SEa to SEd of the spatial light modulator 3a gives to the emitted light on the surface 4c that is a far field region (Fraunhofer diffraction region) of the spatial light modulator 3a. The position is converted.

  Referring to FIG. 1, the incident surface of the cylindrical micro fly's eye lens 8 is positioned at a position optically conjugate with or near the pupil plane 4 c (not shown in FIG. 1) of the afocal lens 4. Therefore, the light intensity distribution (luminance distribution) of the secondary light source formed by the cylindrical micro fly's eye lens 8 is the light intensity distribution SP1 formed on the pupil plane 4c by the spatial light modulator 3a and the front lens group 4a of the afocal lens 4. Distribution according to ~ SP4. As shown in FIG. 5, the spatial light modulator 3 a is a large number of minute reflective elements that are regularly and two-dimensionally arranged along one plane with a planar reflective surface as the upper surface. A movable multi-mirror including a mirror element SE.

  Each mirror element SE is movable, and the inclination of the reflection surface, that is, the inclination angle and the inclination direction of the reflection surface are independently controlled by the action of the drive unit 3ab that operates according to a command from a control unit (not shown). . Each mirror element SE can be rotated continuously or discretely by a desired rotation angle with two directions (X direction and Y direction) parallel to the reflecting surface and orthogonal to each other as rotation axes. . That is, it is possible to two-dimensionally control the inclination of the reflection surface of each mirror element SE.

  In addition, when rotating the reflective surface of each mirror element SE discretely, a rotation angle is made into a several state (For example, ..., -2.5 degree, -2.0 degree, ... 0 degree, +0. It is better to perform switching control at 5 degrees... +2.5 degrees,. Although FIG. 5 shows a mirror element SE having a square outer shape, the outer shape of the mirror element SE is not limited to a square. However, from the viewpoint of light utilization efficiency, it is possible to provide a shape that can be arranged so as to reduce the gap between the mirror elements SE (a shape that can be closely packed). Further, from the viewpoint of light utilization efficiency, the interval between two adjacent mirror elements SE can be minimized.

  In the present embodiment, as the spatial light modulators 3a and 3b, for example, spatial light modulators that continuously change the directions of a plurality of mirror elements SE arranged two-dimensionally are used. As such a spatial light modulator, for example, Japanese Patent Laid-Open No. 10-503300 and European Patent Publication No. 779530 corresponding thereto, Japanese Patent Application Laid-Open No. 2004-78136 and corresponding US Pat. No. 6,900, The spatial light modulator disclosed in Japanese Patent No. 915, Japanese National Publication No. 2006-524349 and US Pat. No. 7,095,546 corresponding thereto and Japanese Patent Application Laid-Open No. 2006-113437 can be used. Note that the directions of the plurality of mirror elements SE arranged two-dimensionally may be controlled so as to have a plurality of stages discretely.

  Thus, in the first spatial light modulator 3a, the attitude of the plurality of mirror elements SE is changed by the action of the drive unit 3ab that operates according to the control signal from the control unit, and each mirror element SE is in a predetermined direction. Set to As shown in FIG. 6, the light reflected by the plurality of mirror elements SE of the first spatial light modulator 3 a at a predetermined angle is applied to the pupil plane of the afocal lens 4, for example, in the Z direction centering on the optical axis AX Two circular light intensity distributions 41a and 41b spaced apart from each other are formed.

  Similarly, in the second spatial light modulator 3b, the posture of the plurality of mirror elements SE of the main body 3ba is changed by the action of the drive unit 3bb that operates according to the control signal from the control unit, and each mirror element SE is changed. Each is set in a predetermined direction. As shown in FIG. 6, the light reflected by the plurality of mirror elements SE of the second spatial light modulator 3b at a predetermined angle is applied to the pupil plane of the afocal lens 4, for example, in the X direction with the optical axis AX as the center. Two circular light intensity distributions 41c and 41d are formed at a distance from each other.

  The light having a quadrupolar light intensity distribution 41 formed on the pupil plane of the afocal lens 4 is incident on the incident surface of the cylindrical micro fly's eye lens 8 and the illumination pupil at or near the rear focal plane of the cylindrical micro fly's eye lens 8. A quadrupolar light intensity distribution corresponding to the light intensity distributions 41a to 41d is formed at the position where the aperture stop 9 is disposed. Furthermore, the light intensity is also applied to another illumination pupil position optically conjugate with the aperture stop 9, that is, the pupil position of the imaging optical system 12 and the pupil position of the projection optical system PL (position where the aperture stop AS is disposed). A quadrupolar light intensity distribution corresponding to the distributions 41a to 41d is formed.

  That is, the afocal lens 4, the zoom lens 7, and the cylindrical micro fly's eye lens 8 are based on the illumination optical system (2 to 12) based on the light flux that has passed through the first spatial light modulator 3 a and the second spatial light modulator 3 b. The distribution forming optical system that forms a predetermined light intensity distribution on the illumination pupil of (1) is configured. The afocal lens 4 and the zoom lens 7 are in the optical path between the cylindrical micro fly's eye lens 8 serving as an optical integrator and the spatial light modulation unit 3 (as a result, between the cylindrical micro fly's eye lens 8 and the deflection surfaces 3da and 3db). A condensing optical system arranged in the optical path between the two.

  In the exposure apparatus, in order to transfer the pattern of the mask M to the wafer W with high accuracy and faithfully, it is important to perform exposure under appropriate illumination conditions corresponding to the pattern characteristics. In the present embodiment, since the spatial light modulation unit 3 including the pair of spatial light modulators 3a and 3b in which the postures of the plurality of mirror elements SE individually change is used, the operation of the first spatial light modulator 3a is performed. Thus, the first light intensity distribution formed on the illumination pupil and the second light intensity distribution formed on the illumination pupil by the action of the second spatial light modulator 3b can be freely and quickly changed.

  That is, an illumination pupil composed of a first light intensity distribution formed on the illumination pupil by the action of the first spatial light modulator 3a and a second light intensity distribution formed on the illumination pupil by the action of the second spatial light modulator 3b. The luminance distribution can be changed freely and quickly. As a result, in the present embodiment, by changing the shape and size of the first light intensity distribution and the second light intensity distribution, various illumination conditions for the shape and size of the illumination pupil luminance distribution are realized. can do.

  Further, in this embodiment, since the spatial light modulation unit 3 including the pair of spatial light modulators 3a and 3b is used, the reflection of the mirror element SE is compared with the case where the spatial light modulator is used alone. The energy per unit area of light incident on the surface is reduced (for example, halved). As a result, in the spatial light modulation unit 3 of the present embodiment, the reflectance of the mirror element SE is unlikely to decrease even when light irradiation is performed over a long period of time, and a required function is stably exhibited over a required period. be able to.

  As described above, in the present embodiment, the illumination optical system (2 to 12) that illuminates the mask M as the irradiated surface based on the light from the light source 1 is a spatial light modulation unit that stably exhibits a required function. 3 is used to realize a variety of illumination conditions with respect to the shape and size of the illumination pupil luminance distribution and to stably exhibit a required function over a required period. Further, in the exposure apparatus (2 to WS) of the present embodiment, the illumination optical system (2 to 12) that realizes a variety of illumination conditions and stably exhibits a required function over a required period is used. Thus, good exposure can be stably performed over a required period under appropriate illumination conditions realized according to the pattern characteristics of the mask M.

  In the present embodiment, the arrangement surface where the plurality of mirror elements SE of the first spatial light modulator 3a are arranged and the arrangement surface where the plurality of mirror elements SE of the second spatial light modulator 3b are arranged are parallel. In addition, the reflecting surfaces of the plurality of mirror elements SE of the first spatial light modulator 3a are opposed to the reflecting surfaces of the plurality of mirror elements SE of the second spatial light modulator 3b. With this configuration, it is possible to reduce the size of the spatial light modulation unit 3 including the pair of spatial light modulators 3a and 3b and the pair of triangular prisms 3c and 3d, and thus to reduce the size of the illumination optical system (2 to 12). it can.

  However, in the configuration in which the light beam shift member 5 is not provided in the present embodiment, as shown in FIG. 7, the first light beam L10 that has passed through the first spatial light modulator 3a and the second light beam L20 that has passed through the second spatial light modulator 3b. Pass through the position of the predetermined plane IP with a relatively large interval in the Z direction. If the first light beam L10 and the second light beam L20 are spaced apart by a relatively large distance at the position of the predetermined surface IP, it is necessary to ensure a large effective diameter of the subsequent optical system such as the zoom lens 7, and consequently illumination. The size of the optical system (2 to 12) will be increased. Therefore, in the present embodiment, the light beam shift member 5 is attached at a position immediately before the predetermined surface IP.

  FIG. 8 shows the reason why the first light flux that has passed through the first spatial light modulator and the second light flux that has passed through the second spatial light modulator are separated from each other at a predetermined distance by a relatively large distance when no light flux shifting member is provided. It is a figure explaining. Referring to FIG. 8, the first light beam L10 and the second light beam L20 are reflected in the reflection regions 30a and 30b in response to the oblique incidence of the light beams on the reflection regions 30a and 30b of the main bodies 3aa and 3ba of the spatial light modulators 3a and 3b. It can be seen that it is emitted in an oblique direction. It can also be seen that the light reflected by the reflection regions 30a and 30b is incident on the deflection surfaces 3da and 3db with a certain angle range α.

  In this case, due to the oblique emission of the light beams L10 and L20 from the reflection areas 30a and 30b and the angle range α of the light from the reflection areas 30a and 30b, virtual images of the reflection areas 30a and 30b (shown by broken lines in FIG. 8). 30aa and 30ba are formed at intervals from the optical axis AX in the Z direction, and the virtual image 30aa of the reflection region 30a and the virtual image 30ba of the reflection region 30b are formed at a relatively large interval. As described above, the position of the predetermined plane IP is substantially optically conjugate with the arrangement surface of the main body 3aa of the first spatial light modulator 3a and the arrangement surface of the main body 3ba of the second spatial light modulator 3b.

  Accordingly, at the position of the predetermined surface IP, the first light beam L10 forms a real image of the reflection region 30a of the first spatial light modulator 3a, and the second light beam L20 forms a real image of the reflection region 30b of the second spatial light modulator 3b. Form. At this time, the real image of the reflection region 30a is formed at a distance in the + Z direction from the optical axis AX similarly to the virtual image 30aa, and the real image of the reflection region 30b is spaced from the optical axis AX in the −Z direction similarly to the virtual image 30ba. Formed. As described above, in the configuration using the pair of spatial light modulators 3a and 3b, unless special measures are taken, the first light beam L10 that has passed through the first spatial light modulator 3a and the first light beam that has passed through the second spatial light modulator 3b. It is impossible to avoid a phenomenon in which the two light beams L20 are separated by a relatively large distance at the position of the predetermined surface IP.

  In the present embodiment, as shown in FIG. 9, the first light beam L10 and the second spatial light modulator that have passed through the first spatial light modulator 3a are provided by attaching the light beam shift member 5 to a position immediately before the predetermined surface IP. The second light beam L20 having passed through 3b is shifted in the Z direction, and as a result, the first light beam L10 and the second light beam L20 are brought close to each other at the position of the predetermined surface IP. Specifically, the light beam shift member 5 includes a first member 5a that shifts the first light beam L10 in the -Z direction, and a second member 5b that shifts the second light beam L20 in the + Z direction. Both the first member 5a and the second member 5b have the form of a plane parallel plate, and the incident surface and the exit surface thereof are disposed obliquely with respect to the XZ plane orthogonal to the optical axis AX.

  In other words, the first member 5a and the second member 5b constituting the light beam shift member 5 are a pair of parallel refracting surfaces (incident incident) arranged obliquely with respect to the XZ plane orthogonal to the optical axis AX. Surface and exit surface). Thus, in the present embodiment, by the action of the light beam shift member 5, the first light beam L10 that has passed through the first spatial light modulator 3a and the second light beam L20 that has passed through the second spatial light modulator 3b are placed at the position of the predetermined plane IP. Since they can be brought close to each other, the effective diameter of the subsequent optical system such as the zoom lens 7 can be kept small, and the illumination optical system (2 to 12) can be downsized.

  In the above description, the light flux shifting member 5 is configured by integrally forming the first member 5a and the second member 5b having the form of a plane parallel plate. However, the present invention is not limited to this, and various forms are possible for the configuration of the light beam shifting member. For example, the light beam shifting member can be constituted by two parallel flat plates as separate optical blocks. For example, as shown in FIG. 10, a so-called V-groove axicon can be used as the light flux shifting member.

  A light beam shifting member 5A according to the modification of FIG. 10 is arranged at a position immediately before the predetermined surface IP, and has a refractive surface 5ca having a convex cross section in order from the light incident side (left side in FIG. 10). And a second prism 5d having a refracting surface 5da having a concave cross section. The refracting surface 5ca having the convex cross section of the first prism 5c and the refracting surface 5da having the concave cross section of the second prism 5d are formed so as to face and complement each other, and these refracting surfaces 5ca and 5da pass through the optical axis AX. It has a V-shaped cross section symmetrical with respect to a predetermined axis extending in the X direction. That is, the pair of refracting surfaces 5ca and 5da are parallel to each other, and the plane portions thereof are arranged obliquely with respect to the XZ plane orthogonal to the optical axis AX.

  The light beam shift member 5A according to the modification of FIG. 10 shifts the first light beam L10 in the −Z direction and the second light beam L20 in the + Z direction, similarly to the light beam shift member 5 according to the embodiment of FIG. Demonstrate the effect. As a result, also in the modified example of FIG. 10, the first light beam L10 that has passed through the first spatial light modulator 3a and the second light beam L20 that has passed through the second spatial light modulator 3b are caused to act on a predetermined surface by the action of the light beam shifting member 5A. Since they can be brought closer to each other at the position of IP, the effective diameter of the subsequent optical system such as the zoom lens 7 can be kept small, and the illumination optical system (2 to 12) can be downsized.

  In the embodiment of FIG. 9 and the modification of FIG. 10, the light beam shift members 5 and 5A are disposed at a position immediately before the predetermined surface IP, and the first light beam L10 and the second space that have passed through the first spatial light modulator 3a. It acts on both of the second light beams L20 that have passed through the light modulator 3b. However, the present invention is not limited to this, and various forms are possible for the arrangement of the light flux shifting member. For example, the light beam shift members 5 and 5A can be arranged at a position immediately after the predetermined surface IP. In general, the light beam shift member is disposed in the optical path between the deflecting surfaces 3da and 3db and the zoom lens 7 (following optical system), and the first light beam L10 and the second light beam L20 are brought close to each other. At least one of the light beam L10 and the second light beam L20 is shifted in a direction crossing the optical axis AX (for example, the Z direction).

  In the above-described embodiment, the first light intensity distribution by the first spatial light modulator 3a and the second light intensity distribution by the second spatial light modulator 3b are formed in different regions in the illumination pupil. However, the present invention is not limited to this, and the first light intensity distribution and the second light intensity distribution may partially overlap each other, or may be completely overlapped (the first light intensity distribution and the second light intensity distribution). The light intensity distribution may be the same distribution and formed at the same position).

  In the above-described embodiment, the triangular prism 3c is used as the divided light guide member, but various forms are possible for the specific configuration of the divided light guide member. In general, the split light guide member splits incident light into a plurality of lights, guides the first light of the plurality of lights to the first spatial light modulator, and converts the second light of the plurality of lights. Guide to the second spatial light modulator. In the above-described embodiment, the deflecting surfaces 3ca and 3cb of the triangular prism 3c form an acute angle and are arranged so as to be convex with respect to the incident light, so that the spatial light modulation unit 3 has a compact design. It becomes possible.

  In the above-described embodiment, since the incident light beam is divided in the short side direction of the rectangular cross section by the triangular prism 3c, the spatial light modulators 3a and 3b can be downsized. In general, when the incident light to the triangular prism 3c has a cross-sectional shape in which the size along the second direction orthogonal to the first direction is larger than the size along the first direction, By dividing the incident light in the first direction, the spatial light modulators 3a and 3b can be downsized.

  In the above-described embodiment, the rear deflection member deflects the first light beam L10 that has passed through the first spatial light modulator 3a and the second light beam L20 that has passed through the second spatial light modulator 3b toward the subsequent optical system. Although the triangular prism 3d is used, various forms of the specific configuration of the rear deflection member are possible. In general, the rear deflection member includes a first deflection surface that deflects the first light flux that has passed through the first spatial light modulator toward the subsequent optical system, and a second light flux that has passed through the second spatial light modulator as the subsequent optical light. And a second deflection surface that deflects toward the system.

  In the above description, as the spatial light modulator having a plurality of optical elements that are two-dimensionally arranged and individually controlled, the direction (angle: inclination) of the two-dimensionally arranged reflecting surfaces is set. An individually controllable spatial light modulator is used. However, the present invention is not limited to this. For example, a spatial light modulator that can individually control the height (position) of a plurality of two-dimensionally arranged reflecting surfaces can be used. As such a spatial light modulator, for example, Japanese Patent Application Laid-Open No. 6-281869 and US Pat. No. 5,312,513 corresponding thereto, and Japanese Patent Laid-Open No. 2004-520618 and US Patent corresponding thereto are disclosed. The spatial light modulator disclosed in FIG. 1d of Japanese Patent No. 6,885,493 can be used. In these spatial light modulators, by forming a two-dimensional height distribution, an action similar to that of the diffractive surface can be given to incident light. Note that the spatial light modulator having a plurality of two-dimensionally arranged reflection surfaces described above is disclosed in, for example, Japanese Patent Laid-Open No. 2006-513442 and US Pat. No. 6,891,655 corresponding thereto, or a special table. You may deform | transform according to the indication of 2005-524112 gazette and the US Patent Publication 2005/0095749 corresponding to this.

  In the above description, a reflective spatial light modulator having a plurality of mirror elements is used. However, the present invention is not limited to this. For example, transmission disclosed in US Pat. No. 5,229,872 A type of spatial light modulator may be used.

  In the above description, a spatial light modulator having a plurality of optical elements is used. However, the present invention is not limited to this, and a reflective diffractive optical element and a transmissive diffractive optical element can be used as the spatial light modulator. Alternatively, a mirror array element in which a plurality of fixed minute reflecting surfaces are arranged in a two-dimensional array may be used. In this case as well, the light efficiency in the spatial light modulator is likely to deteriorate over time due to the relatively large energy per unit area of the light incident on the spatial light modulator. Is difficult to stably perform a required function over a required period of time ”, and“ the entrance side and the exit side of the spatial light modulator due to the increase in the size of the spatial light modulator ” This can solve both of the problems of the present invention that lead to an increase in the size of the optical system (lens, prism, mirror, etc.).

  In the above-described embodiment, when the illumination pupil luminance distribution is formed using the spatial light modulation unit, the illumination pupil luminance distribution is measured by the pupil luminance distribution measuring device, and the spatial light modulation unit in the spatial light modulation unit is measured according to the measurement result. Each spatial light modulator may be controlled. Such a technique is disclosed in, for example, Japanese Patent Application Laid-Open No. 2006-54328 and Japanese Patent Application Laid-Open No. 2003-22967 and US Patent Publication No. 2003/0038225 corresponding thereto.

  In the above-described embodiment, a variable pattern forming apparatus that forms a predetermined pattern based on predetermined electronic data can be used instead of a mask. By using such a variable pattern forming apparatus, the influence on the synchronization accuracy can be minimized even if the pattern surface is placed vertically. As the variable pattern forming apparatus, for example, a DMD (digital micromirror device) including a plurality of reflecting elements driven based on predetermined electronic data can be used. An exposure apparatus using DMD is disclosed in, for example, Japanese Patent Application Laid-Open No. 2004-304135 and International Patent Publication No. 2006/080285. In addition to a non-light-emitting reflective spatial light modulator such as DMD, a transmissive spatial light modulator may be used, or a self-luminous image display element may be used. Note that a variable pattern forming apparatus may be used even when the pattern surface is placed horizontally.

  The exposure apparatus of the above-described embodiment is manufactured by assembling various subsystems including the respective constituent elements recited in the claims of the present application so as to maintain predetermined mechanical accuracy, electrical accuracy, and optical accuracy. Is done. In order to ensure these various accuracies, before and after assembly, various optical systems are adjusted to achieve optical accuracy, various mechanical systems are adjusted to achieve mechanical accuracy, and various electrical systems are Adjustments are made to achieve electrical accuracy. The assembly process from the various subsystems to the exposure apparatus includes mechanical connection, electrical circuit wiring connection, pneumatic circuit piping connection and the like between the various subsystems. Needless to say, there is an assembly process for each subsystem before the assembly process from the various subsystems to the exposure apparatus. When the assembly process of the various subsystems to the exposure apparatus is completed, comprehensive adjustment is performed to ensure various accuracies as the entire exposure apparatus. The exposure apparatus may be manufactured in a clean room where the temperature, cleanliness, etc. are controlled.

  Next, a device manufacturing method using the exposure apparatus according to the above-described embodiment will be described. FIG. 11 is a flowchart showing a manufacturing process of a semiconductor device. As shown in FIG. 11, in the semiconductor device manufacturing process, a metal film is vapor-deposited on a wafer W to be a semiconductor device substrate (step S40), and a photoresist, which is a photosensitive material, is applied on the vapor-deposited metal film. (Step S42). Subsequently, using the projection exposure apparatus of the above-described embodiment, the pattern formed on the mask (reticle) M is transferred to each shot area on the wafer W (step S44: exposure process), and the wafer W after the transfer is completed. Development, that is, development of the photoresist to which the pattern has been transferred (step S46: development process). Thereafter, using the resist pattern generated on the surface of the wafer W in step S46 as a mask, processing such as etching is performed on the surface of the wafer W (step S48: processing step).

  Here, the resist pattern is a photoresist layer in which unevenness having a shape corresponding to the pattern transferred by the projection exposure apparatus of the above-described embodiment is generated, and the recess penetrates the photoresist layer. It is. In step S48, the surface of the wafer W is processed through this resist pattern. The processing performed in step S48 includes, for example, at least one of etching of the surface of the wafer W or film formation of a metal film or the like. In step S44, the projection exposure apparatus of the above-described embodiment performs pattern transfer using the wafer W coated with the photoresist as the photosensitive substrate, that is, the plate P.

  FIG. 12 is a flowchart showing a manufacturing process of a liquid crystal device such as a liquid crystal display element. As shown in FIG. 12, in the liquid crystal device manufacturing process, a pattern formation process (step S50), a color filter formation process (step S52), a cell assembly process (step S54), and a module assembly process (step S56) are sequentially performed.

  In the pattern forming process of step S50, a predetermined pattern such as a circuit pattern and an electrode pattern is formed on the glass substrate coated with a photoresist as the plate P using the projection exposure apparatus of the above-described embodiment. The pattern forming step includes an exposure step of transferring the pattern to the photoresist layer using the projection exposure apparatus of the above-described embodiment, and development of the plate P on which the pattern is transferred, that is, development of the photoresist layer on the glass substrate. And a developing step for generating a photoresist layer having a shape corresponding to the pattern, and a processing step for processing the surface of the glass substrate through the developed photoresist layer.

  In the color filter forming process in step S52, a large number of sets of three dots corresponding to R (Red), G (Green), and B (Blue) are arranged in a matrix or three R, G, and B A color filter is formed by arranging a plurality of stripe filter sets in the horizontal scanning direction.

  In the cell assembly process in step S54, a liquid crystal panel (liquid crystal cell) is assembled using the glass substrate on which the predetermined pattern is formed in step S50 and the color filter formed in step S52. Specifically, for example, a liquid crystal panel is formed by injecting liquid crystal between a glass substrate and a color filter. In the module assembling process in step S56, various components such as an electric circuit and a backlight for performing the display operation of the liquid crystal panel are attached to the liquid crystal panel assembled in step S54.

  In addition, the present invention is not limited to application to an exposure apparatus for manufacturing a semiconductor device, for example, an exposure apparatus for a display device such as a liquid crystal display element formed on a square glass plate or a plasma display, It can also be widely applied to an exposure apparatus for manufacturing various devices such as an image sensor (CCD, etc.), micromachine, thin film magnetic head, and DNA chip. Furthermore, the present invention can also be applied to an exposure process (exposure apparatus) when manufacturing a mask (photomask, reticle, etc.) on which mask patterns of various devices are formed using a photolithography process.

In the above-described embodiment, ArF excimer laser light (wavelength: 193 nm) or KrF excimer laser light (wavelength: 248 nm) is used as the exposure light. However, the present invention is not limited to this, and other appropriate laser light sources are used. For example, the present invention can also be applied to an F ₂ laser light source that supplies laser light having a wavelength of 157 nm.

  In the above-described embodiment, a so-called immersion method is applied in which the optical path between the projection optical system and the photosensitive substrate is filled with a medium (typically liquid) having a refractive index larger than 1.1. You may do it. In this case, as a method for filling the liquid in the optical path between the projection optical system and the photosensitive substrate, a method for locally filling the liquid as disclosed in International Publication No. WO 99/49504, A method of moving a stage holding a substrate to be exposed as disclosed in Japanese Patent Application Laid-Open No. 6-124873 in a liquid bath, or a predetermined depth on a stage as disclosed in Japanese Patent Application Laid-Open No. 10-303114. A technique of forming a liquid tank and holding the substrate in the liquid tank can be employed. Here, the teachings of International Publication No. WO99 / 49504, JP-A-6-124873 and JP-A-10-303114 are incorporated by reference.

  In the above-described embodiment, the polarization illumination method may be applied. Polarized illumination methods are disclosed, for example, in US Pat. No. 7,423,731, and US Patent Publication Nos. 2006/0203214, 2006/0158624, and 2006/0170901.

  In the above-described embodiment, the present invention is applied to the illumination optical system that illuminates the mask in the exposure apparatus. However, the present invention is not limited to this, and a general illumination surface other than the mask is illuminated. The present invention can also be applied to an illumination optical system.

DESCRIPTION OF SYMBOLS 1 Light source 3 Spatial light modulation unit 3a, 3b Spatial light modulator 3c, 3d Triangular prism 4 Afocal lens 5, 5A Light beam shift member 7 Zoom lens 8 Cylindrical micro fly's eye lens 10 Condenser optical system 11 Mask blind 12 Imaging optical system SE A plurality of mirror elements M of the spatial light modulators 3a and 3b M Mask PL Projection optical system W Wafer

Claims (21)

In the illumination optical system that illuminates the illuminated surface based on the light from the light source,
A first spatial light modulator that emits the incident light after applying spatial light modulation;
A second spatial light modulator that emits light after applying spatial light modulation to the incident light;
A first deflecting surface for deflecting the first light flux that has passed through the first spatial light modulator toward a subsequent optical system;
A second deflecting surface for deflecting the second light flux that has passed through the second spatial light modulator toward the subsequent optical system;
The first light beam and the second light beam are disposed in an optical path between the first deflection surface and the second deflection surface and the subsequent optical system so as to bring the first light beam and the second light beam closer to each other. An illumination optical system comprising: a light beam shift member that shifts at least one of the two light beams in a direction crossing the optical axis. The illumination optical system according to claim 1, wherein the light beam shifting member has a pair of refractive surfaces disposed obliquely with respect to a surface orthogonal to the optical axis. The illumination optical system according to claim 2, wherein the pair of refractive surfaces are parallel to each other. The light flux shifting member includes a first member that shifts the first light flux in a direction crossing the optical axis, and a second member that shifts the second light flux in a direction crossing the optical axis. The illumination optical system according to any one of claims 1 to 3. The illumination optical system according to claim 4, wherein the first member and the second member are integrally formed. The illumination optical system according to claim 4, wherein the first member and the second member have a form of a plane parallel plate. The light beam shifting member includes, in order from the light incident side, a first prism having a convex sectional refractive surface, and a concave sectional refractive surface formed complementary to the convex sectional refractive surface of the first prism. The illumination optical system according to claim 5, wherein the refracting surface has a V-shaped cross section symmetrical with respect to a predetermined axis passing through the optical axis. The first spatial light modulator and the second spatial light modulator each include a plurality of optical elements that are two-dimensionally arranged and individually controlled. The illumination optical system described in 1. The first spatial light modulator and the second spatial light modulator each have a plurality of two-dimensionally arranged mirror elements and a drive unit that individually controls and drives the postures of the plurality of mirror elements. The illumination optical system according to claim 8. The array surface on which the plurality of mirror elements of the first spatial light modulator are arranged is parallel to the array surface on which the plurality of mirror elements of the second spatial light modulator are arranged, and the first space. The illumination optical system according to claim 9, wherein the reflection surfaces of the plurality of mirror elements of the light modulator are opposed to the reflection surfaces of the plurality of mirror elements of the second spatial light modulator. 11. The illumination optical system according to claim 9, wherein the driving unit changes the directions of the plurality of mirror elements continuously or discretely. 2. The traveling direction in a reference state of light emitted from the first deflection surface and the traveling direction in a reference state of light emitted from the second deflection surface are parallel to the optical axis. 12. The illumination optical system according to any one of 11 to 11. The incident light is divided into a plurality of lights, a first light of the plurality of lights is guided to the first spatial light modulator, and a second light of the plurality of lights is modulated by the second spatial light modulation. The illumination optical system according to any one of claims 1 to 12, further comprising a divided light guide member that leads to a vessel. The divided light guide member includes a third deflection surface that deflects incident light toward the first spatial light modulator, and a fourth deflection surface that deflects incident light toward the second spatial light modulator. The incident light is divided into the first light and the second light along a ridge line between the third deflection surface and the fourth deflection surface. Lighting optics. The illumination optical system according to claim 14, wherein an angle formed between the third deflection surface and the fourth deflection surface is an acute angle. The incident light has a cross-sectional shape in which the size along the second direction orthogonal to the first direction is larger than the size along the first direction in the cross section of the incident light;
The illumination optical system according to claim 13, wherein the divided light guide member divides the incident light in the first direction. 2. A distribution forming optical system that forms a predetermined light intensity distribution in an illumination pupil based on light that has passed through the first spatial light modulator and the second spatial light modulator. The illumination optical system according to any one of 1 to 16. The distribution forming optical system includes: an optical integrator; and a condensing optical system disposed in an optical path between the first deflection surface, the second deflection surface, and the optical integrator. 18. An illumination optical system according to item 17. The projection pupil is used in combination with a projection optical system that forms a surface optically conjugate with the irradiated surface, and the illumination pupil is at a position optically conjugate with an aperture stop of the projection optical system. The illumination optical system according to 17 or 18. An exposure apparatus comprising the illumination optical system according to any one of claims 1 to 19 for illuminating a predetermined pattern, and exposing the predetermined pattern onto a photosensitive substrate. An exposure step of exposing the predetermined pattern to the photosensitive substrate using the exposure apparatus according to claim 20;
Developing the photosensitive substrate to which the predetermined pattern is transferred, and forming a mask layer having a shape corresponding to the predetermined pattern on the surface of the photosensitive substrate;
And a processing step of processing the surface of the photosensitive substrate through the mask layer.

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