JP2011023559A - Spatial light modulation unit, illumination optical system, exposure device, and device manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a spatial light modulation unit that stably exhibits necessary functions of an incorporated spatial light modulator for a necessary period. <P>SOLUTION: The spatial light modulation unit (3) used for an illumination optical system which irradiates a surface to be irradiated based on light from a light source includes four spatial light modulators (31, 32, 33, and 34) arranged in parallel to one another and having a plurality of mirror elements two-dimensionally arrayed and individually controlled, and selective light guide parts (35, 36, 37, and 38) that selectively guide the light made incident from the light source on at least three of the four spatial light modulators. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a spatial light modulation unit, 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 “pupil intensity 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 optical system 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 pupil intensity 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 pupil intensity 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 in changing the shape and size of the pupil intensity distribution is high, but the movable multi-mirror as a spatial light modulator is used alone. Therefore, the energy per unit area of the light incident on the reflecting surface of the mirror element becomes 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 spatial light modulator to stably perform a required function over a required period.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a spatial light modulation unit that can stably exhibit a required function of a built-in spatial light modulator over a required period. And An illumination optical system capable of stably realizing a wide variety of illumination conditions by using a spatial light modulation unit that stably exhibits the required functions of the built-in spatial light modulator over a required period. The purpose is to provide. In addition, the present invention uses an illumination optical system that stably realizes a wide variety of illumination conditions, and performs good exposure under appropriate illumination conditions realized according to the characteristics of the pattern to be transferred. An object of the present invention is to provide an exposure apparatus that can be used.

In order to solve the above-mentioned problem, according to the first aspect of the present invention, there is provided a spatial light modulation unit used in an illumination optical system that illuminates an irradiated surface based on light from a light source,
First to third spatial light modulators having a plurality of mirror elements arranged in parallel to each other and arranged two-dimensionally and individually controlled;
A spatial light modulation unit, comprising: a selective light guide unit that selectively guides light incident from the light source to at least one of the first to third spatial light modulators; I will provide a.

In the second embodiment of the present invention, in the illumination optical system that illuminates the illuminated surface based on the light from the light source,
A spatial light modulation unit of the first form;
A distribution forming optical system that forms a predetermined light intensity distribution on an illumination pupil of the illumination optical system based on light that has passed through at least one of the first to third spatial light modulators. An illumination optical system is provided.

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

In the fourth embodiment of the present invention, using the exposure apparatus of the third 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 spatial light modulation unit of the present invention, three reflective spatial light modulators are arranged in parallel in the illumination light path, and illumination light is selectively guided to at least one spatial light modulator. Therefore, it is possible to change the pupil intensity distribution freely and quickly by using the three spatial light modulators at the same time, and to realize various illumination conditions for the shape and size of the pupil intensity distribution. Also, by using the three spatial light modulators simultaneously, the energy per unit area of the light incident on the reflecting surface of the mirror element is kept small, and the required functions of each spatial light modulator can be stably performed over the required period. It can be demonstrated. In addition, even if an arbitrary spatial light modulator fails, the operation of the apparatus can be continued using another spatial light modulator, and thus the failed spatial light modulator can be replaced without stopping the apparatus. it can.

  Thus, the illumination optical system according to the present invention uses the spatial light modulation unit that stably exhibits the required function of the built-in spatial light modulator over a required period, and has a variety of shapes and sizes of the pupil intensity distribution. A wide variety of lighting conditions can be realized. The exposure apparatus of the present invention uses the illumination optical system that realizes a wide variety of illumination conditions, and performs good exposure under appropriate illumination conditions realized according to the characteristics of the pattern to be transferred. Which can be done and thus a good device can be produced.

It is a figure which shows schematically the structure of the exposure apparatus concerning embodiment of this invention. FIG. 2 is a first diagram schematically showing an internal configuration of the spatial light modulation unit in FIG. 1. FIG. 3 is a second diagram schematically showing the internal configuration of the spatial light modulation unit in FIG. 1. It is a figure which shows a mode that three front side deflection | deviation members divide an incident light beam into 4 parts. It is a figure explaining the effect | action of the spatial light modulator in a spatial light modulation unit. It is a fragmentary perspective view of the principal part of a spatial light modulator. It is a figure which shows typically the ring-shaped light intensity distribution formed in the entrance plane and back side focal plane of a micro fly's eye lens. It is a figure which shows a mode that two front side deflection | deviation members divide an incident light beam into 3 at the time of failure of a 3rd spatial light modulator. It is a figure which shows a mode that three front side deflection | deviation members divide an incident light beam into 3 at the time of failure of a 2nd spatial light modulator. It is a figure which shows the modification which divides an incident light beam into about 3 equally with two front side deflection members at the time of failure of a 3rd spatial light modulator. It is a figure which shows schematically the internal structure of the spatial light modulation unit concerning the modification of FIG. It is a figure which shows schematically the internal structure of the spatial light modulation unit concerning the modification to which the polarization illumination method is applied. It is a figure which shows schematically the structure of the polarizing element of FIG. It is a figure which shows typically the annular zone pupil intensity distribution obtained in the modification of FIG. 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. 2 and 3 are diagrams schematically showing an internal configuration of the spatial light modulation unit of FIG. 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 enters the relay optical system 4 via the beam transmitter 2 and the spatial light modulation unit 3. The beam transmitter 2 guides the incident light beam from the light source 1 to the spatial light modulation unit 3 while converting the incident light beam into a light beam having an appropriate size and shape, and changes the position of the light beam incident on the spatial light modulation unit 3. And a function of actively correcting the angular variation.

  As shown in FIGS. 2 and 3, the spatial light modulation unit 3 includes four spatial light modulators 31, 32, 33, and 34 arranged in parallel in the illumination optical path. Each of the spatial light modulators 31 to 34 has a plurality of mirror elements that are two-dimensionally arranged and individually controlled. A parallel plane plate 35 that can be inclined with respect to the optical axis AX is disposed on the most light source side in the optical path on the light source side (left side in FIGS. 2 and 3) from the four spatial light modulators 31 to 34. . A deflecting member 36 is disposed in the optical path between the plane parallel plate 35 and the first spatial light modulator 31 and the second spatial light modulator 32.

  A deflection member 37 is disposed in the optical path between the plane parallel plate 35 and the third spatial light modulator 33, and a deflection member 38 is disposed in the optical path between the plane parallel plate 35 and the fourth spatial light modulator 34. Is arranged. A deflection member 39 is disposed in the optical path between the first spatial light modulator 31 and the second spatial light modulator 32 and the relay optical system 4. A deflection member 40 is disposed in the optical path between the third spatial light modulator 33 and the relay optical system 4, and the deflection member 41 is disposed in the optical path between the fourth spatial light modulator 34 and the relay optical system 4. Is arranged.

  Hereinafter, in order to facilitate understanding of the description, it is assumed that the plane-parallel plate 35 is set to a reference posture in which the incident surface and the emission surface are orthogonal to the optical axis AX. In this case, the three front deflection members 36 to 38 divide the light beam from the light source 1 into four parts, guide the first light beam to the first spatial light modulator 31, and guide the second light beam to the second spatial light modulator 32. The third light beam is guided to the third spatial light modulator 33 and the fourth light beam is guided to the fourth spatial light modulator 34. The three rear deflection members 39 to 41 guide the light that has passed through the spatial light modulators 31 to 34 to the relay optical system 4. The specific configuration and operation of the spatial light modulation unit 3 will be described later. In FIG. 2, the deflection members 37, 38, 40, and 41 are not shown for clarity.

  Light emitted from the spatial light modulation unit 3 enters the predetermined surface 5 via the relay optical system 4. The relay optical system 4 has a front focal position that substantially coincides with the position of the array surface of the plurality of mirror elements of each of the spatial light modulators 31 to 34 and a rear focal position that substantially coincides with the position of the predetermined plane 5. Is set. As will be described later, the light that has passed through each of the spatial light modulators 31 to 34 variably forms a light intensity distribution on the predetermined surface 5 in accordance with the postures of the plurality of mirror elements.

  The light having the light intensity distribution formed on the predetermined surface 5 enters the micro fly's eye lens (or fly eye lens) 7 via the relay optical system 6. The relay optical system 6 sets the predetermined surface 5 and the incident surface of the micro fly's eye lens 7 optically conjugate. Therefore, the light that has passed through the spatial light modulation unit 3 has the same outer shape as the light intensity distribution formed on the predetermined surface 5 on the incident surface of the micro fly's eye lens 7 that is optically conjugate with the predetermined surface 5. The light intensity distribution is formed.

  The micro fly's eye lens 7 is an optical element made up of a large number of micro lenses having positive refractive power, which are arranged vertically and horizontally and densely. The micro fly's eye lens 7 is configured by forming a micro lens group by etching a plane parallel plate. Has been. In a micro fly's eye lens, unlike a fly eye lens composed of lens elements isolated from each other, a large number of micro lenses (micro refractive surfaces) are integrally formed without being isolated from each other. However, the micro fly's eye lens is the same wavefront division type optical integrator as the fly's eye lens in that the lens elements are arranged vertically and horizontally.

  A rectangular minute refracting surface as a unit wavefront dividing surface in the micro fly's eye lens 7 is a rectangular shape similar to the shape of the illumination field to be formed on the mask M (and the shape of the exposure region to be formed on the wafer W). It is. For example, a cylindrical micro fly's eye lens can be used as the micro fly's eye lens 7. The configuration and action of the cylindrical micro fly's eye lens are disclosed in, for example, US Pat. No. 6,913,373.

  The light beam incident on the micro fly's eye lens 7 is two-dimensionally divided by a large number of microlenses, and the light intensity distribution on the rear focal plane or in the vicinity of the illumination pupil is almost the same as the light intensity distribution formed on the incident plane. A secondary light source (substantially surface light source consisting of a large number of small light sources: pupil intensity distribution) is formed. The light beam from the secondary light source formed on the illumination pupil immediately after the micro fly's eye lens 7 enters an illumination aperture stop (not shown). The illumination aperture stop is disposed at the rear focal plane of the micro fly's eye lens 7 or in the vicinity thereof, and has an opening (light transmission portion) having a shape corresponding to the secondary light source.

  The illumination aperture stop is configured to be detachable with respect to the illumination optical path, and is configured to be switchable with a plurality of aperture stops having apertures having different sizes and shapes. As a method for switching the illumination aperture stop, for example, a known turret method or slide method can be used. The illumination aperture stop is disposed at a position 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 installation of the illumination aperture stop can also be omitted.

  The light from the secondary light source limited by the illumination aperture stop illuminates the mask blind 9 in a superimposed manner via the condenser optical system 8. Thus, a rectangular illumination field corresponding to the shape and focal length of the rectangular micro-refractive surface of the micro fly's eye lens 7 is formed on the mask blind 9 as an illumination field stop. The light beam that has passed through the rectangular opening (light transmitting portion) of the mask blind 9 receives the light condensing action of the imaging optical system 10 and then illuminates the mask M on which a predetermined pattern is formed in a superimposed manner. That is, the imaging optical system 10 forms an image of the rectangular opening of the mask blind 9 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 exposure apparatus according to the present embodiment includes a pupil intensity distribution measurement unit DT that measures the pupil intensity distribution on the pupil plane of the projection optical system PL based on light via the projection optical system PL, and a measurement result of the pupil intensity distribution measurement unit DT. And a control unit CR that controls the spatial light modulators 31 to 34 in the spatial light modulation unit 3. The pupil intensity distribution measurement unit DT includes, for example, a CCD image pickup unit having an image pickup surface disposed at a position optically conjugate with the pupil position of the projection optical system PL, and the pupil intensity relating to each point on the image plane of the projection optical system PL. The distribution (pupil intensity distribution formed at the pupil position of the projection optical system PL by the light incident on each point) is monitored. For the detailed configuration and operation of the pupil intensity distribution measuring unit DT, reference can be made to, for example, US Patent Publication No. 2008/0030707.

  In this embodiment, the secondary light source formed by the micro fly's eye lens 7 is used as a light source, and the mask M (and thus the wafer W) disposed on the irradiated surface of the illumination optical system is Koehler illuminated. For this reason, the position where the secondary light source is formed is optically conjugate with the position of the aperture stop AS of the projection optical system PL, and the formation surface of the secondary light source can be called the illumination pupil plane of the illumination optical system. Typically, the irradiated surface (the surface on which the mask M is disposed or the surface on which the wafer W is disposed when the illumination optical system including the projection optical system PL is considered) is optical with respect to the illumination pupil plane. A Fourier transform plane. The pupil intensity distribution is a light intensity distribution (luminance distribution) on the illumination pupil plane of the illumination optical system or a plane optically conjugate with the illumination pupil plane.

  When the number of wavefront divisions by the micro fly's eye lens 7 is relatively large, the overall light intensity distribution formed on the incident surface of the micro fly's eye lens 7 and the overall light intensity distribution (pupil intensity distribution) of the entire secondary light source. ) And a high correlation. For this reason, the light intensity distribution on the incident surface of the micro fly's eye lens 7 and a surface optically conjugate with the incident surface can also be referred to as a pupil intensity distribution. In the configuration of FIG. 1, the relay optical systems 4 and 6 and the micro fly's eye lens 7 are illuminated immediately after the micro fly's eye lens 7 based on the light beams that have passed through the spatial light modulators 31 to 34 in the spatial light modulation unit 3. A distribution forming optical system that forms a pupil intensity distribution on the pupil is configured.

  Next, the internal configuration and operation of the spatial light modulation unit 3 will be specifically described. The plane-parallel plate 35 is rotatable about a first axis (not shown) extending in the X direction through the optical axis AX and rotatable about a second axis (not shown) extending in the Z direction through the optical axis AX. It is configured. As a result, the parallel flat plate 35 serving as the herbing is rotated from the reference posture shown in FIGS. 2 and 3 by an arbitrary angle around the first axis in accordance with a command from the control unit CR, or from the reference posture to the second position. It can take a posture rotated by an arbitrary angle around the axis. In the plane-parallel plate 35 set to the reference posture, the incident surface and the exit surface are orthogonal to the optical axis AX, and thus parallel to the XZ plane.

  The deflecting members 36 and 39 have, for example, a triangular prism prism mirror shape extending in the X direction. The deflecting member 36 has a pair of reflecting surfaces 36a and 36b facing the light source, and the ridge line between the reflecting surfaces 36a and 36b extends in the X direction through the optical axis AX. The deflecting member 39 has a pair of reflecting surfaces 39a and 39b facing the mask side, and the ridge line between the reflecting surfaces 39a and 39b extends in the X direction through the optical axis AX. As shown in FIG. 4, when viewed from the light source side along the optical axis AX, the pair of integral reflecting surfaces 36 a and 36 b as a whole have an elongated rectangular outer shape along the Z direction. Although not shown, when viewed from the mask side along the optical axis AX, the pair of integral reflecting surfaces 39a and 39b also have an elongated rectangular outer shape as a whole along the Z direction.

  The deflecting members 37, 38, 40, 41 have, for example, a triangular prism prism mirror shape extending in the Z direction. The deflecting members 37 and 38 have reflecting surfaces 37a and 38a facing the light source. As shown in FIG. 4, when viewed from the light source side along the optical axis AX, the reflecting surface 37 a of the deflecting member 37 is disposed so as to be in contact with the end edges of the reflecting surfaces 36 a and 36 b on the + X direction side, and the deflecting member 38. The reflecting surface 38a is disposed so as to be in contact with the end edges of the reflecting surfaces 36a and 36b on the −X direction side.

  Although not shown, when viewed from the mask side along the optical axis AX, the reflecting surface 40a of the deflecting member 40 is disposed so as to be in contact with the + X direction side edge portions of the reflecting surfaces 39a and 39b. The reflective surface 41a of 41 is disposed so as to be in contact with the end edges of the reflective surfaces 39a and 39b on the −X direction side. The deflecting members 36 to 41 are formed by providing a reflective film made of aluminum, silver, or the like on the side surface of a triangular prism-shaped member formed of a non-optical material such as metal or an optical material such as quartz. You can also Alternatively, each of the deflecting members 36 to 41 can be formed as a mirror.

  In a normal state where the plane-parallel plate 35 is set to the reference posture, the parallel light beam incident on the spatial light modulation unit 3 along the optical axis AX is refracted by the incident surface and the exit surface of the plane-parallel plate 35. After passing as it is, it enters the deflecting members 36-38. As shown in FIG. 4, among the incident light beams to the deflection members 36 to 38, for example, the incident light beam F <b> 0 having a rectangular cross section, the first light beam having a rectangular cross section reflected by the first reflecting surface 36 a of the deflection member 36. The one light beam F01 enters the first spatial light modulator 31, and the second light beam F02 having a rectangular cross section reflected by the second reflecting surface 36b enters the second spatial light modulator 32.

  The third light beam F03 having a rectangular cross section reflected by the reflecting surface 37a of the deflecting member 37 is incident on the third spatial light modulator 33 and has a rectangular cross section reflected by the reflecting surface 38a of the deflecting member 38. The fourth light flux F04 is incident on the fourth spatial light modulator 34. Hereinafter, in order to simplify the description, the cross-sectional shape of the incident light beam F0 and the incident position of the incident light beam F0 on the deflecting members 36 to 38 are set so that the light beams F01 to F04 have substantially the same cross section. Shall.

  The light modulated by the first spatial light modulator 31 is reflected by the first reflecting surface 39 a of the deflecting member 39 and guided to the relay optical system 4. The light modulated by the second spatial light modulator 32 is reflected by the second reflecting surface 39 b of the deflecting member 39 and guided to the relay optical system 4. The light modulated by the third spatial light modulator 33 is reflected by the reflecting surface 40 a of the deflecting member 40 and guided to the relay optical system 4. The light modulated by the fourth spatial light modulator 34 is reflected by the reflecting surface 41 a of the deflecting member 41 and guided to the relay optical system 4.

  Hereinafter, in order to simplify the description, each of the spatial light modulators 31 to 34 has the same configuration, and the array surface of the plurality of mirror elements of the first spatial light modulator 31 and the second spatial light modulator 32 It is assumed that the array surface of the plurality of mirror elements is arranged symmetrically with respect to a surface including the optical axis AX and parallel to the XY plane. The array surface of the plurality of mirror elements of the third spatial light modulator 33 and the array surface of the plurality of mirror elements of the fourth spatial light modulator 34 are symmetric with respect to a plane that includes the optical axis AX and is parallel to the YZ plane. It shall be arranged in. That is, each of the spatial light modulators 31 to 34 is arranged such that the array surface of the plurality of mirror elements is parallel to the optical axis AX.

  Similarly, the first reflecting surface 36a and the second reflecting surface 36b of the deflecting member 36 and the first reflecting surface 39a and the second reflecting surface 39b of the deflecting member 39 are surfaces including the optical axis AX and parallel to the XY plane. Are arranged symmetrically. Further, the reflecting surface 37a of the deflecting member 37, the reflecting surface 38a of the deflecting member 38, and the reflecting surface 40a of the deflecting member 40 and the reflecting surface 41a of the deflecting member 41 are related to a plane parallel to the YZ plane including the optical axis AX. Assume that they are arranged symmetrically. Therefore, the description which overlaps with the 1st spatial light modulator 31 about the three spatial light modulators 32-34 is abbreviate | omitted, paying attention to the 1st spatial light modulator 31, each spatial light modulator in the spatial light modulation unit 3 The configuration and operation of 31 to 34 will be described.

  As shown in FIG. 5, the spatial light modulator 31 is connected to a plurality of mirror elements 31a that are two-dimensionally arranged along the XY plane, a base 31b that holds the plurality of mirror elements 31a, and a base 31b. And a drive unit 31c that individually controls and drives the postures of the plurality of mirror elements 31a via cables (not shown). As shown in FIG. 6, the spatial light modulator 31 includes a plurality of minute mirror elements 31a arranged two-dimensionally, and the spatial modulation corresponding to the incident position of the incident light can be varied. Is applied and injected. For ease of explanation and illustration, FIG. 5 and FIG. 6 show a configuration example in which the spatial light modulator 31 includes 4 × 4 = 16 mirror elements 31a. Are provided with a number of mirror elements 31a.

  Referring to FIG. 5, a group of light beams incident on the first reflecting surface 36 a of the deflecting member 36 (not shown in FIG. 5) along the direction parallel to the optical axis AX and reflected toward the spatial light modulator 31. Of these, the light beam L1 is incident on the mirror element SEa of the plurality of mirror elements 31a, and the light beam L2 is incident on the 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 31, in a reference state in which the reflecting surfaces of all the mirror elements 31a are set along one plane (XY plane), the light beam incident on the reflecting surface 36a along the direction parallel to the optical axis AX. Is reflected by the first reflecting surface 39a of the deflecting member 39 (not shown in FIG. 5) in a direction substantially parallel to the optical axis AX after being reflected by the spatial light modulator 31. . Further, the array surface of the plurality of mirror elements 31a of the spatial light modulator 31 is positioned at or near the front focal position of the relay optical system 4 as described above.

  Therefore, the light reflected by the plurality of mirror elements SEa to SEd of the spatial light modulator 31 and given a predetermined angular distribution forms the predetermined light intensity distributions SP1 to SP4 on the predetermined surface 5, and thus the micro fly's eye A light intensity distribution corresponding to the light intensity distributions SP1 to SP4 is formed on the incident surface of the lens 7. In other words, the relay optical system 4 determines the angle that the plurality of mirror elements SEa to SEd of the spatial light modulator 31 gives to the emitted light on the predetermined surface 5 that is the far field region (Fraunhofer diffraction region) of the spatial light modulator 31. Convert to position at.

  Similarly, the light modulated by the other three spatial light modulators 32 to 34 forms a light intensity distribution corresponding to the diffraction characteristics on the predetermined surface 5 and thus on the incident surface of the micro fly's eye lens 7. Thus, the light intensity distribution (pupil intensity distribution) of the secondary light source formed by the micro fly's eye lens 7 is formed on the incident surface of the micro fly's eye lens 7 by the first spatial light modulator 31 and the relay optical systems 4 and 6. A first light intensity distribution, a second light intensity distribution formed on the incident surface of the micro fly's eye lens 7 by the second spatial light modulator 32 and the relay optical systems 4 and 6, a third spatial light modulator 33 and The third optical intensity distribution formed on the incident surface of the micro fly's eye lens 7 by the relay optical systems 4 and 6, and the fourth spatial light modulator 34 and the relay optical systems 4 and 6 on the incident surface of the micro fly's eye lens 7. The distribution corresponds to the combined distribution with the fourth light intensity distribution to be formed. Here, the first to fourth light intensity distributions may be isolated from each other, may be partially or entirely overlapped with each other, or may be randomly mixed as will be described later. It may be.

  As shown in FIG. 6, the spatial light modulator 31 is a large number of minute reflective elements that are regularly and two-dimensionally arranged along one plane with a planar reflective surface as an upper surface. A movable multi-mirror including a mirror element 31a. Each mirror element 31a 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 31c that operates according to a command from the control unit CR. Each mirror element 31a can rotate continuously or discretely by a desired rotation angle about two directions (for example, X direction and Y direction) parallel to the reflecting surface and orthogonal to each other. it can. That is, it is possible to two-dimensionally control the inclination of the reflecting surface of each mirror element 31a.

  In addition, when rotating the reflective surface of each mirror element 31a discretely, a rotation angle is 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. 6 shows a mirror element 31a having a square outer shape, the outer shape of the mirror element 31a 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 that the gap between the mirror elements 31a is reduced (a shape that can be closely packed). Further, from the viewpoint of light utilization efficiency, the interval between two adjacent mirror elements 31a can be minimized.

  In the present embodiment, as the spatial light modulator 31, for example, a spatial light modulator that continuously changes the directions of a plurality of mirror elements 31a arranged two-dimensionally is 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 31a arranged two-dimensionally may be controlled so as to have a plurality of discrete stages.

  In the spatial light modulator 31, the attitude of the plurality of mirror elements 31a is changed by the action of the drive unit 31c that operates according to the control signal from the control unit CR, and each mirror element 31a is set in a predetermined direction. The As shown in FIG. 7, the light reflected by the plurality of mirror elements 31a of the spatial light modulator 31 at a predetermined angle is incident on the incident surface of the micro fly's eye lens 7, for example, in the Z direction with the optical axis AX as the center. A pair of arc-shaped light intensity distributions 20a are formed at intervals.

  Similarly, the light that has passed through the second spatial light modulator 32 forms, for example, a pair of arc-shaped light intensity distributions 20b that are spaced apart in the X direction about the optical axis AX. The light that has passed through the third spatial light modulator 33 forms, for example, a pair of arc-shaped light intensity distributions 20c that are spaced from each other in the first oblique direction that forms 45 degrees with the X direction and the Z direction with the optical axis AX as the center. . The light that has passed through the fourth spatial light modulator 34 forms, for example, a pair of arc-shaped light intensity distributions 20d spaced from each other in the second oblique direction perpendicular to the first oblique direction with the optical axis AX as the center. Thus, the light that has passed through the four spatial light modulators 31 to 34 forms, for example, an annular light intensity distribution 20 (20a to 20d) centered on the optical axis AX on the incident surface of the micro fly's eye lens 7.

  As a result, an annular light intensity distribution 21 (21a to 21d) corresponding to the annular light intensity distribution 20 is formed on the rear focal plane of the micro fly's eye lens 7 or in the vicinity of the illumination pupil. Further, the position of another illumination pupil that is optically conjugate with the illumination pupil at or near the rear focal plane of the micro fly's eye lens 7, that is, the pupil position of the imaging optical system 10 and the pupil position (aperture) of the projection optical system PL. An annular light intensity distribution corresponding to the annular light intensity distribution 20 is also formed at the position where the aperture stop AS is disposed.

  In the present embodiment, when the third spatial light modulator 33 fails, the parallel plane plate 35 is set to the first posture rotated by a required angle around the second axis extending in the Z direction from the reference posture shown in FIG. . The plane parallel plate 35 set in the first posture translates the incident light flux by a required distance in the −X direction, and the two front deflection members 36 and 38 divide the incident light flux F1 into three as shown in FIG. In this case, the light beam F11 having a rectangular cross section reflected by the first reflecting surface 36a of the deflecting member 36 enters the first spatial light modulator 31, and the rectangular cross section reflected by the second reflecting surface 36b is reflected. The light flux F <b> 12 having the incident light enters the second spatial light modulator 32.

  The light beam F14 having a rectangular cross section reflected by the reflecting surface 38a of the deflecting member 38 enters the fourth spatial light modulator 34. Since the light flux F1 does not enter the reflecting surface 37a of the deflecting member 37, a part of the light flux F1 is not guided to the failed third spatial light modulator 33. Here, the incident light beam F1 has the same cross section as the incident light beam F0 in FIG. 4, the light beams F11 and F12 have the same cross section as the light beams F01 and F02 in FIG. 4, and the light beam F14 has the light beams F03 and F04 in FIG. Have the same cross section.

  Thus, when the third spatial light modulator 33 fails, for example, the light that has passed through the spatial light modulator 31 forms a pair of arc-shaped light intensity distributions 20a, and the light that has passed through the spatial light modulator 32 has a pair of arc shapes. The light intensity distribution 20b is formed, and the light passing through the spatial light modulator 34 forms a pair of arc-shaped light intensity distributions 20c and a pair of arc-shaped light intensity distributions 20d. That is, even if the third spatial light modulator 33 breaks down, the operation of the apparatus can be continued using the other three spatial light modulators 31, 32, 34, and thus the failed space without stopping the apparatus. The light modulator 33 can be replaced.

  Although not shown, when the fourth spatial light modulator 34 fails, the incident light beam is translated in the + X direction by the parallel flat plate 35 serving as a herbing, and the incident light beam is converted to 3 by the two front deflection members 36 and 37. Divide it. As a result, even if the fourth spatial light modulator 34 breaks down, the operation of the device can be continued using the other three spatial light modulators 31 to 33, and thus the failed spatial light without stopping the device. The modulator 34 can be replaced.

  Next, when the second spatial light modulator 32 fails, the parallel plane plate 35 is set to the second posture rotated by a required angle around the first axis extending in the X direction from the reference posture shown in FIG. The incident light beam F2 is divided into three by the three front deflection members 36 and 3738 as shown in FIG. In this case, the light beam F <b> 21 having a rectangular cross section reflected by the first reflecting surface 36 a of the deflecting member 36 enters the first spatial light modulator 31.

  The light beam F23 having a rectangular cross section reflected by the reflecting surface 37a of the deflecting member 37 is incident on the third spatial light modulator 33 and is reflected by the reflecting surface 38a of the incident deflecting member 38. F 24 enters the fourth spatial light modulator 34. Since the light beam F2 does not enter the second reflecting surface 36b of the deflecting member 36, a part of the light beam F2 is not guided to the failed second spatial light modulator 32. Here, the incident light beam F2 has the same cross section as the incident light beam F0 in FIG. 4, the light beams F23 and F24 have the same cross section as the light beams F03 and F04 in FIG. 4, and the light beam F21 has the light beams F01 and F02 in FIG. Have the same cross section.

  Thus, when the second spatial light modulator 32 fails, for example, the light passing through the spatial light modulator 31 forms a pair of arc-shaped light intensity distributions 20a and a pair of arc-shaped light intensity distributions 20b. The light passing through the device 33 forms a pair of arc-shaped light intensity distributions 20c, and the light passing through the spatial light modulator 34 forms a pair of arc-shaped light intensity distributions 20d. That is, even if the second spatial light modulator 32 breaks down, the operation of the apparatus can be continued using the other three spatial light modulators 31, 33, 34, and thus the failed space without stopping the apparatus. The light modulator 32 can be exchanged.

  Although not shown, when the first spatial light modulator 31 fails, the incident light beam is translated in the −Z direction by the parallel flat plate 35 serving as a herb, and incident by the three front deflection members 36, 37, and 38. What is necessary is just to divide a light beam into 3 parts. As a result, even if the first spatial light modulator 31 breaks down, the operation of the apparatus can be continued using the other three spatial light modulators 32 to 34, and thus the failed spatial light without stopping the apparatus. The modulator 31 can be exchanged.

  As described above, in the spatial light modulation unit 3 of the present embodiment used in the illumination optical system (2 to 10) that illuminates the mask M as the irradiated surface based on the light from the light source 1, there are four reflective types. Spatial light modulators 31 to 34 are arranged in parallel in the illumination optical path, and the illumination light is selectively guided to at least three arbitrary spatial light modulators by the action of the plane parallel plate 35 as a herb. As a result, in the spatial light modulation unit 3 of the present embodiment, the pupil intensity distribution can be freely and quickly changed by simultaneously using at least three spatial light modulators, and the shape and size of the pupil intensity distribution is rich in diversity. Lighting conditions can be realized.

  Further, in the spatial light modulation unit 3 of the present embodiment, even in a normal state where the four spatial light modulators 31 to 34 are used at the same time, the three spatial light modulators are used simultaneously when one spatial light modulator fails. Even in an emergency state, the energy per unit area of the light incident on the reflecting surface of the mirror element SE is kept small (for example, 1/4 or 1/3) as compared with the case where the spatial light modulator is used alone. It is done. As a result, in each spatial light modulator, the reflectance of the mirror element SE is not easily lowered, and a required function can be stably exhibited over a required period.

  Further, in the spatial light modulation unit 3 of the present embodiment, even if an arbitrary spatial light modulator fails, the other three spatial lights excluding the failed spatial light modulator due to the action of the parallel plane plate 35 as the herbing. Illumination light can be directed to the modulator. As a result, even when the spatial light modulator fails, the operation of the apparatus can be continued using the other three spatial light modulators. As a result, the failed spatial light modulator can be replaced without stopping the apparatus. .

  Thus, in the illumination optical system (2 to 10) of the present embodiment, the spatial light modulation unit 3 that stably exhibits the required functions of the built-in spatial light modulators 31 to 34 over a required period is used. Various illumination conditions can be realized with respect to the shape and size of the pupil intensity distribution. In the exposure apparatus (2 to WS) of the present embodiment, the illumination optical system (2 to 10) that realizes a wide variety of illumination conditions is used according to the pattern characteristics of the mask M to be transferred. Good exposure can be performed under the appropriate illumination conditions.

  In the above-described embodiment, the parallel plane plate 35 that can be tilted with respect to the optical axis AX constitutes a light flux moving section that translates and emits the light flux incident from the light source 1. However, the present invention is not limited to this, and various configurations are possible for the configuration of the light flux moving unit. For example, the light flux moving unit can be configured using a pair of mirrors.

  In the above-described embodiment, the light incident from the light source 1 is selected as at least three spatial light modulators by the parallel flat plate 35 that can be tilted with respect to the optical axis AX and the three front deflection members 36 to 38. The selective light guide part which guides automatically is comprised. However, the present invention is not limited to this, and various configurations are possible for the configuration of the selective light guide unit. A first front deflection surface (corresponding to the reflection surface 36a) that deflects the light beam incident through the light beam moving portion toward the first spatial light modulator, and a second front deflection surface that deflects the light beam toward the second spatial light modulator. (Corresponding to the reflecting surface 36b), a third front deflecting surface (corresponding to the reflecting surface 37a) that deflects toward the third spatial light modulator, and a fourth front deflecting surface that deflects toward the fourth spatial light modulator. (Corresponding to the reflecting surface 38a) can be configured as separate mirrors, for example.

  In the above-described embodiment, when the third spatial light modulator 33 (or the fourth spatial light modulator 34) fails, the incident light beam F1 having the same cross section as the incident light beam F0 in FIG. 4 is divided into three. However, as shown in FIG. 10, an incident light beam F1 'having a cross-sectional aspect ratio different from that of the incident light beam F1 can be divided into approximately three equal parts by the two front deflection members 36 and 38 (or 37). As shown in FIG. 11, the incident light beam F <b> 1 ′ is obtained, for example, by the action of the light beam cross-section variable member 42 arranged in the optical path on the light source side with respect to the parallel flat plate (light beam moving unit) 35.

  The beam cross-section variable member 42 has an afocal zoom lens including a plurality of cylindrical lenses, for example, and emits the cross-sectional shape of the incident light beam by independently changing it in the X direction and the Z direction. In some cases, the beam cross-section variable member 42 may be disposed in the optical path between the parallel flat plate 35 and the front deflection members 36 to 38. Further, by adopting a configuration in which the light beam cross-section variable member 42 includes a diffractive optical element, the cross-sectional shape of the incident light beam can be freely changed and emitted.

  In the embodiment shown in FIG. 10, when the spatial light modulator 33 (or 34) fails, the light that has passed through the other three spatial light modulators 31, 32, 34 (or 33) is, for example, an annular light intensity distribution 20. May be formed according to a random form. In this case, each mirror element of the three spatial light modulators 31, 32, 34 (or 33) and each small light source forming the annular light intensity distribution 20 have a one-to-one correspondence with each other at random. The influence of the positional deviation of the incident light beam on the optical axis AX on the pupil intensity distribution can be reduced. The method of randomly making a one-to-one correspondence between each mirror element of the spatial light modulator to be used and each small light source of the pupil intensity distribution is not limited to the number of spatial light modulators to be used, the shape of the pupil intensity distribution, etc. Applicable.

  In the configuration shown in FIG. 11, the light beam corresponding to the light beam F01 of FIG. 4 is incident on the first reflecting surface 36a of the deflecting member 36 by the cooperative action of the parallel flat plate 35 as the herbing and the light beam cross-section variable member 42. In addition, a light beam corresponding to the light beam F02 can be incident on the second reflecting surface 36b of the deflecting member 36. Further, the light beam corresponding to the light beam F01 in FIG. 4 is incident only on the first reflecting surface 36a of the deflecting member 36, or the light beam corresponding to the light beam F02 in FIG. 4 is incident only on the second reflecting surface 36b of the deflecting member 36. Can be.

  Similarly, the light beam corresponding to the light beam F03 in FIG. 4 is incident only on the reflection surface 37a of the deflection member 37, or the light beam corresponding to the light beam F04 in FIG. 4 is incident only on the reflection surface 38a of the deflection member 38. Can do. That is, in the configuration shown in FIG. 11, light incident from the light source 1 can be selectively guided to at least one spatial light modulator, so that even if three spatial light modulators fail at the same time, the device The failed spatial light modulator can be replaced without stopping the operation.

  In the above-described embodiment, the light beam that has passed through the plane-parallel plate 35 serving as the light beam moving unit has a rectangular cross section, and the cross sections of the light beams that are wavefront-divided by the three front deflection members 36 to 38 are also rectangular. It is. However, the present invention is not limited to this, and various forms are possible with respect to the cross-sectional shape and size of the light beam that has passed through the light beam moving unit, the cross-sectional shape and size of each light beam that is wavefront divided by a plurality of front deflection surfaces, and the like. .

  Also, a so-called polarization illumination method can be applied to the above-described embodiment. As an example, as shown in FIG. 12, by providing a polarizing element 43 in an optical path closer to the light source than the plane-parallel plate 35 serving as a light flux moving unit, for example, annular illumination in a circumferentially polarized state can be performed. it can. In some cases, the polarizing element 43 may be provided in an optical path between the plane-parallel plate 35 and the front deflection members 36 to 38.

  As shown in FIG. 13, the polarizing element 43 includes four parallel plane plate-shaped optical rotation members 43a, 43b, 43c, and 43d having different thicknesses. Each of the optical rotation members 43a to 43d is formed of a crystal material that is an optical material having optical activity, for example, quartz. In a state where the polarizing element 43 is positioned in the optical path, the incident surfaces (and thus the exit surfaces) of the optical rotation members 43a to 43d are orthogonal to the optical axis AX, and the crystal optical axis thereof is substantially coincident with the optical axis AX (that is, incident light). In the direction of travel). The four optical rotation members 43a to 43d are divided so that the respective light beams F31 to F34 corresponding to the respective light beams F01 to F04 divided into four by the front deflection members 36 to 38 pass therethrough.

  The optical rotatory member 43a through which the light flux F31 incident on the first reflecting surface 36a of the deflecting member 36 passes, when X direction linearly polarized light having a polarization direction in the Z direction is incident, has an X direction straight line having the polarization direction in the X direction. The thickness is set so as to emit polarized light. The optical rotation member 43b through which the light flux F32 incident on the second reflecting surface 36b of the deflecting member 36 passes is set to have a thickness so as to emit the Z-direction linearly polarized light when the Z-direction linearly polarized light is incident. Yes.

  The optical rotatory member 43c through which the light flux F33 incident on the reflecting surface 37a of the deflecting member 37 passes has a polarization direction in a first oblique direction that forms 45 degrees with the X direction and the Y direction when light in the Z direction linearly polarized light enters. The thickness is set so as to emit the first obliquely linearly polarized light. The optical rotatory member 43d through which the light flux F34 incident on the reflecting surface 38a of the deflecting member 38 passes has a second oblique direction having a polarization direction in a second oblique direction orthogonal to the first oblique direction when light in the Z direction linearly polarized light is incident. The thickness is set so as to emit directional linearly polarized light.

  Therefore, when the Z-direction linearly polarized light is incident on the polarizing element 43, as shown in FIG. 14, the optical rotation member of the annular pupil intensity distribution 21 formed on the illumination pupil immediately after the micro fly's eye lens 7 is used. The polarization direction of the pair of arc-shaped light intensity distributions 21a formed by the light beam F31 subjected to the optical rotation action 34a is the X direction, and the pair of arc-shaped lights formed by the light flux F32 subjected to the optical rotation action of the optical rotation member 34b. The polarization direction of the intensity distribution 21b is the Z direction. The polarization directions of the pair of arc-shaped light intensity distributions 21c and the pair of arc-shaped light intensity distributions 21d formed by the light beam F33 subjected to the optical rotation action of the optical rotation member 34c and the light flux F34 subjected to the optical rotation action of the optical rotation member 34d are oblique. Become a direction. As a result, the pupil intensity distribution 21 in the circumferential polarization state is obtained by the action of the polarizing element 43. Although illustration is omitted, when X-directional linearly polarized light is incident on the polarizing element 43, a pupil intensity distribution in a radially polarized state is obtained in the illumination pupil immediately after the micro fly's eye lens 7.

  In general, in circumferential polarization illumination based on a circumferentially polarized state ring-shaped or multipolar pupil intensity distribution, the light irradiated to the wafer W as the final irradiated surface is a polarization state whose main component is S-polarized light become. Here, the S-polarized light is linearly polarized light having a polarization direction in a direction perpendicular to the incident surface (polarized light having an electric vector oscillating in a direction perpendicular to the incident surface). However, the incident surface is defined as a surface including the normal of the boundary surface at that point and the incident direction of light when the light reaches the boundary surface of the medium (surface to be irradiated: the surface of the wafer W). The As a result, in the circumferential polarization illumination, the optical performance (such as depth of focus) of the projection optical system can be improved, and a mask pattern image with high contrast can be obtained on the wafer (photosensitive substrate).

  In the configuration of FIG. 12, the polarizing element 43 for circumferentially polarized illumination (or for radially polarized illumination) is formed by the four optical rotation members 43a to 43d. However, the present invention is not limited to this, and various forms are possible with respect to the specific configuration of the polarizing element, and thus the type of polarized illumination realized by the polarizing element, and a polarizing element having required characteristics can be obtained as necessary. Positioned in the illumination light path. For example, instead of an optical rotation member, a plurality of types of wave plates that change incident light into light having a required polarization state, a plurality of types of polarizers that select and emit light having a required polarization state from incident light, and the like are used. In addition, a polarizing element that realizes various polarized illuminations corresponding to various incident light beams can be configured.

  Further, in the above-described embodiment, the four spatial light modulators 31 to 34 are arranged in parallel in the illumination optical path, and the array planes of the pair of spatial light modulators 31 and 32 are parallel to each other across the optical axis AX. The arrangement surfaces of the pair of spatial light modulators 33 and 34 are arranged in parallel with each other with the optical axis AX interposed therebetween. The light incident from the light source 1 is selectively guided to at least three spatial light modulators. However, the present invention is not limited to this, and the number of spatial light modulators arranged in parallel in the optical path, the positional relationship between the arrangement surfaces of the spatial light modulators, and the spatial light modulator from which illumination light is selectively guided Various forms are possible for the number of In general, in the present invention, three or more spatial light modulators having a plurality of mirror elements that are two-dimensionally arranged and individually controlled are arranged in parallel in the illumination light path, and It is important that the incident light is selectively directed to at least one spatial light modulator.

  In the above description, the operational effects of the present invention are described by taking, as an example, modified illumination in which an annular pupil intensity distribution is formed on the illumination pupil, that is, annular illumination. However, the illumination is not limited to the annular illumination, for example, circular illumination in which a circular pupil intensity distribution is formed, and multipolar illumination in which a multipolar (bipolar, quadrupolar, etc.) pupil intensity distribution is formed. It is apparent that the same effects can be obtained by applying the present invention to the above.

  Further, in the above description, as the spatial light modulator having a plurality of mirror elements that are two-dimensionally arranged and individually controlled, the direction (angle: inclination) of the plurality of 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-described embodiment, the micro fly's eye lens 7 is used as the optical integrator, but instead, an internal reflection type optical integrator (typically a rod type integrator) may be used. In this case, a condensing optical system that condenses light from the predetermined surface 5 is disposed instead of the relay optical system 6. Then, instead of the micro fly's eye lens 7 and the condenser optical system 8, a rod type is used so that the incident end is positioned at or near the rear focal position of the condensing optical system that condenses the light from the predetermined surface 5. Place the integrator. At this time, the injection end of the rod-type integrator is positioned at the mask blind 9. When a rod type integrator is used, a position optically conjugate with the position of the aperture stop AS of the projection optical system PL in the imaging optical system 10 downstream of the rod type integrator can be called an illumination pupil plane. In addition, since a virtual image of the secondary light source of the illumination pupil plane is formed at the position of the entrance surface of the rod integrator, this position and a position optically conjugate with this position are also called the illumination pupil plane. Can do. Here, the condensing optical system, the imaging optical system, and the rod integrator can be regarded as a distribution forming optical system.

  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, International Patent Publication No. 2006/080285 pamphlet and US Patent Publication No. 2007/0296936 corresponding thereto. 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. Here, the teachings of US Patent Publication No. 2007/0296936 are incorporated by reference. In the case where a plurality of DMDs are used as the variable pattern forming device, a configuration may be adopted in which light is guided to the plurality of DMDs using the light beam splitting element according to the present embodiment.

  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. 15 is a flowchart showing a manufacturing process of a semiconductor device. As shown in FIG. 15, 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. 16 is a flowchart showing a manufacturing process of a liquid crystal device such as a liquid crystal display element. As shown in FIG. 16, in the manufacturing process of the liquid crystal device, 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 or the like), a micromachine, a thin film magnetic head, and a 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 technique for filling the liquid in the optical path between the projection optical system and the photosensitive substrate, a technique for locally filling the liquid as disclosed in International Publication No. WO99 / 49504, a special technique, A method of moving a stage holding a substrate to be exposed as disclosed in Kaihei 6-124873 in a liquid bath, or a predetermined stage on a stage as disclosed in JP-A-10-303114. A method of forming a liquid tank having a depth and holding the substrate therein 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 present invention is applied to the illumination optical system that illuminates the mask (or wafer) in the exposure apparatus. However, the present invention is not limited to this, and an object other than the mask (or wafer) is used. The present invention can also be applied to a general illumination optical system that illuminates the irradiation surface.

DESCRIPTION OF SYMBOLS 1 Light source 2 Beam transmission part 3 Spatial light modulation units 31-34 Reflection type spatial light modulator 35 Inclinable parallel plane plates 36-41 Deflection members 4 and 6 Relay optical system 7 Micro fly's eye lens 8 Condenser optical system 9 Mask blind 10 Imaging optical system DT Pupil intensity distribution measurement unit CR Control unit M Mask MS Mask stage PL Projection optical system W Wafer WS Wafer stage

Claims (20)

A spatial light modulation unit used in an illumination optical system that illuminates an illuminated surface based on light from a light source,
First to third spatial light modulators having a plurality of mirror elements arranged in parallel to each other and arranged two-dimensionally and individually controlled;
A spatial light modulation unit, comprising: a selective light guide unit that selectively guides light incident from the light source to at least one of the first to third spatial light modulators; . The selective light guide is
A light flux moving unit that translates and emits a light flux incident from the light source;
A first front deflection surface that deflects the light beam incident through the light beam moving portion toward the first spatial light modulator;
A second front deflection surface that deflects the light beam incident through the light beam moving portion toward the second spatial light modulator;
2. The spatial light modulation unit according to claim 1, further comprising: a third front deflection surface configured to deflect a light beam incident through the light beam moving unit toward the third spatial light modulator. 3. The spatial light modulation unit according to claim 2, wherein the light flux moving unit includes a parallel plane plate that can be inclined with respect to an optical axis of the illumination optical system. The light flux that has passed through the light flux moving section has a rectangular cross section,
The first to third front deflection surfaces are arranged so that each light beam divided by the first to third front deflection surfaces has a rectangular cross section. 4. The spatial light modulation unit according to 3. The first to third spatial light modulators are arranged such that an array surface of the plurality of mirror elements is parallel to an optical axis of the illumination optical system. The spatial light modulation unit according to claim 1. The selective light guide portion is provided in an optical path closer to the light source than the first to third front deflection surfaces, and the first polarization state light beam and the first polarization state are based on an incident light beam. The spatial light modulation unit according to any one of claims 2 to 5, further comprising a polarizing element that generates light beams having different second polarization states. The spatial light modulation unit according to claim 6, wherein the polarizing element is provided so as to be disposed in an optical path closer to the light source than the light flux moving unit. The polarizing element is formed of an optical material having optical rotation and having a first thickness and a parallel plane plate-like first optical rotation member, and is formed of an optical material having optical rotation and having the first thickness. The spatial light modulation unit according to claim 6, further comprising: a second optical rotation member having a plane-parallel plate shape having different second thicknesses. The polarization element includes a first wavelength plate that changes incident light into light in the first polarization state, and a second wavelength that changes incident light into light in the second polarization state different from the first linear polarization state. The spatial light modulation unit according to claim 6, further comprising a plate. The polarizing element includes a first polarizer that selects and emits light in the first polarization state from incident light, and a second polarizer that selects and emits light in the second polarization state from incident light. The spatial light modulation unit according to claim 6 or 7, characterized by the above. The selective light guide section includes a light beam cross-section variable member that is arranged in the optical path on the light source side relative to the first to third front deflection surfaces and emits the light by changing the cross-sectional shape of the incident light beam. The spatial light modulation unit according to any one of claims 2 to 10. The spatial light modulation unit according to claim 11, wherein the beam cross-section variable member is disposed on an optical path closer to the light source than the beam moving unit. The said 1st thru | or 3rd spatial light modulator has a drive part which changes the direction of these mirror elements continuously or discretely, respectively, The one of Claim 1 thru | or 12 characterized by the above-mentioned. Spatial light modulation unit. A first rear deflection surface for deflecting light having passed through the first spatial light modulator toward a subsequent optical system; and a first rear deflecting surface for deflecting light having passed through the second spatial light modulator toward the subsequent optical system. 14. A second rear deflection surface, and a third rear deflection surface for deflecting light having passed through the third spatial light modulator toward the subsequent optical system. The spatial light modulation unit according to any one of the above. In the illumination optical system that illuminates the illuminated surface based on light from the light source,
The spatial light modulation unit according to any one of claims 1 to 14,
A distribution forming optical system that forms a predetermined light intensity distribution on an illumination pupil of the illumination optical system based on light that has passed through at least one of the first to third spatial light modulators. An illumination optical system. 16. The illumination optical system according to claim 15, wherein the distribution forming optical system includes an optical integrator and a condensing optical system disposed in an optical path between the optical integrator and the spatial light modulation unit. system. 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 15 or 16. An exposure apparatus comprising the illumination optical system according to any one of claims 15 to 17 for illuminating a predetermined pattern, and exposing the predetermined pattern onto a photosensitive substrate. 19. The exposure apparatus according to claim 18, further comprising a projection optical system that forms an image of the predetermined pattern on the photosensitive substrate. An exposure step of exposing the predetermined pattern to the photosensitive substrate using the exposure apparatus according to claim 18 or 19,
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.

Images