JP2017129866A - Illumination optical system, exposure device, exposure method, and device manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an illumination optical system capable of achieving a desired polarization state of pupil intensity distribution at good accuracy.SOLUTION: An illumination optical system for illuminating a surface to be illuminated by light from a light source has a plurality of optical elements which are controlled individually by being aligned in a predetermined surface and has a space light modulation device which adjustably forms light intensity distribution on an illumination pupil of the illumination optical system, a polarization member which is provided in a conjugation space containing a surface optically conjugated with the predetermined surface and changes a polarization state of a part of light bundles in transmission light bundles transmitting a light passage and a light intensity distribution uniformizing member which is provided in a light passage between the light source and the polarization member and enhances uniformity of intensity distribution of light injected to the predetermined surface.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an illumination optical system, an exposure apparatus, and a device manufacturing method.

  In an exposure apparatus used for manufacturing a device such as a semiconductor element, a light source emitted from a light source is a secondary light source (generally a surface light source consisting of a number of light sources via a fly-eye lens as an optical integrator). Form a predetermined light intensity distribution in the illumination pupil. 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 from the secondary light source is collected 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 miniaturized, and it is indispensable to obtain a uniform illuminance 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, for example, 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.

US Patent Application Publication No. 2009/0116093

  In the illumination optical system described in Patent Document 1, since a spatial light modulator having a plurality of mirror elements whose postures are individually controlled is used, the shape of the pupil intensity distribution (wide concept including size) is changed. The degree of freedom regarding is high. However, in order to realize a desired illumination condition suitable for transferring a fine pattern, it is desired to accurately realize a desired polarization state of a pupil intensity distribution.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide an illumination optical system capable of accurately realizing a desired polarization state of a pupil intensity distribution. The present invention also provides an exposure apparatus and device capable of transferring a fine pattern to a photosensitive substrate under an appropriate illumination condition using an illumination optical system that accurately realizes a desired polarization state of a pupil intensity distribution. An object is to provide a manufacturing method.

In order to solve the above-described problem, in the first embodiment, in the illumination optical system that illuminates the illuminated surface with light from the light source,
A spatial light modulator having a plurality of optical elements arranged on a predetermined surface and individually controlled, and variably forming a light intensity distribution on the illumination pupil of the illumination optical system;
A polarizing member disposed in a conjugate space including a position near the predetermined surface or a surface optically conjugate with the predetermined surface and changing a polarization state of a part of the propagating light beams propagating through the optical path; ,
An illumination comprising: a light intensity distribution uniforming member disposed in an optical path between the light source and the polarizing member to improve uniformity of intensity distribution of light incident on the predetermined surface. An optical system is provided.

  According to a second aspect, 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, using the exposure apparatus of the second embodiment, exposing the predetermined pattern to the photosensitive substrate;
Developing the photosensitive substrate having the predetermined pattern transferred thereon, and forming a mask layer having a shape corresponding to the predetermined pattern on the surface of the photosensitive substrate;
And processing the surface of the photosensitive substrate through the mask layer. A device manufacturing method is provided.

It is a figure which shows schematically the structure of the exposure apparatus concerning embodiment. It is a figure explaining the structure and effect | action of a spatial light modulator. It is a fragmentary perspective view of the principal part of a spatial light modulator. It is a figure which expands and shows the optical path from a lens array to the pupil plane of a relay optical system in the shape of a straight line. It is a figure which shows schematically the structure of the polarizing member concerning embodiment. It is a figure which shows a mode that a light beam injects into the position of the polarizing member of FIG. It is a figure which shows the polarization state of the light beam immediately after the polarizing member of FIG. It is a figure which shows the partial area | region of the arrangement surface of the spatial light modulator in embodiment. It is a figure which shows the pupil intensity distribution of the 4-polar shape and circumferential direction polarization state formed in embodiment. It is a figure which shows the pupil intensity distribution of the quadrupolar shape and radial direction polarization state formed in embodiment. It is a figure which shows a mode that a light beam injects into the position of the polarizing member provided with a pair of 1/2 wavelength plate. It is a figure which shows the polarization state of the light beam immediately after the polarizing member of FIG. It is a figure which shows the partial area | region of the arrangement surface of the spatial light modulator in the modification of FIG. It is a figure which shows the pupil intensity distribution of the hexapolar shape and circumferential direction polarization state which are formed 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.

  Hereinafter, embodiments will be described with reference to the accompanying drawings. FIG. 1 is a view schematically showing a configuration of an exposure apparatus according to the 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 LS. As the light source LS, 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 LS in the + Z direction is incident on the optical path bending mirror MR1 via the beam transmitter 1, the lens array 2a, and the relay optical system 2b. The light reflected in the oblique direction by the optical path bending mirror MR1 enters the spatial light modulator 3.

  As will be described later, the spatial light modulator 3 individually controls the postures of a plurality of mirror elements arranged in a predetermined plane and individually controlled based on a control signal from the control system CR. And a driving unit for driving. The beam transmitting unit 1 guides the incident light beam from the light source LS to the spatial light modulator 3 while converting the incident light beam into a light beam having a cross section having an appropriate size and shape, and arranges a plurality of mirror elements of the spatial light modulator 3. It has a function of actively correcting positional fluctuations and angular fluctuations of light incident on a plane (hereinafter referred to as “spatial light modulator array plane”).

  The lens array 2a is composed of, for example, a plurality of lens elements arranged vertically and horizontally along a plane orthogonal to the optical axis AX and densely. The light beam incident from the light source LS via the beam transmitting unit 1 is converted into a plurality of light beams. Divide the wavefront. The plurality of light beams that have been wavefront-divided by the lens array 2a are superimposed on the array surface of the spatial light modulator 3 via the relay optical system 2b. That is, the lens array 2a and the relay optical system 2b as wavefront dividing elements constitute a light intensity distribution uniforming member 2 that improves the uniformity of the intensity distribution of light incident on the spatial light modulator 3. Here, the focal position of each lens element of the lens array 2a (or the position of the divergence origin of the plurality of light beams divided by the wavefront) and the front focal position of the relay optical system 2b substantially coincide with each other, and the relay optical system 2b. The rear focal position and the incident surface of the diffractive optical element 3 substantially coincide with each other.

  A beam splitter BS is disposed in the optical path between the relay optical system 2b and the optical path bending mirror MR1, and the light extracted from the illumination optical path by the beam splitter BS enters the beam monitor BM. The beam monitor BM is based on the light extracted from the illumination optical path, the position of the light incident on the spatial light modulator 3 in the array plane, the angle of the light incident on the spatial light modulator 3 with respect to the array plane, and the spatial light. The light intensity distribution on the arrangement surface of the modulator 3 is monitored.

  The monitoring result of the beam monitor BM is supplied to the control system CR. The control system CR controls the beam transmitter 1 and the spatial light modulator 3 based on the output of the beam monitor BM. The beam monitor BM is, for example, a position optically conjugate with the arrangement surface of the spatial light modulator 3 (on the lens array 2a) in order to monitor the light incident position and light intensity distribution on the arrangement surface of the spatial light modulator 3. In order to monitor the incident angle of light on the first imaging unit having a photoelectric conversion surface arranged at a position substantially optically Fourier-transformed with respect to the arrangement surface of light incident on the spatial light modulator 3. And a second imaging unit having a photoelectric conversion surface arranged at a position (optically conjugate with the lens array 2a) that is substantially optically Fourier transformed with respect to the arrangement surface of the spatial light modulator 3. You may have. The internal configuration of the beam monitor BM is disclosed in, for example, US Patent Publication No. 2011/0069305.

  In the optical path between the spatial light modulator 3 and the optical path bending mirror MR1, the polarization state of a part of the propagating light beam propagating in the optical path is displayed at a position near the arrangement surface of the spatial light modulator 3. A polarizing member 4 to be changed is provided. The configuration and operation of the spatial light modulator 3 and the polarizing member 4 will be described later.

  The light emitted from the spatial light modulator 3 in the + Z direction is incident on the pupil plane 5 c of the relay optical system 5 through the front lens group 5 a of the relay optical system 5. The front lens group 5a is set so that its front focal position substantially coincides with the position of the array surface of the spatial light modulator 3, and its rear focal position substantially coincides with the position of the pupil plane 5c. As will be described later, the light that has passed through the spatial light modulator 3 variably forms a light intensity distribution according to the postures of the plurality of mirror elements on the pupil plane 5c. The light that forms the light intensity distribution on the pupil surface 5 c enters the relay optical system 6 via the rear lens group 5 b of the relay optical system 5. The relay optical system 6 has a front focal position located near the rear focal position of the rear lens group 5 b of the relay optical system 5 and a rear focal position located near the incident surface of the micro fly's eye lens 7. The rear focal position of the rear lens group 5b of the relay optical system 5 and the arrangement surface of the spatial light modulator 3 and the incident surface of the micro fly's eye lens 7 are optically set in a Fourier transform relationship. ing.

  The light that has passed through the relay optical system 6 is reflected in the + Y direction by the optical path bending mirror MR2, and enters the micro fly's eye lens (or fly eye lens) 7. The rear lens group 5b and the relay optical system 6 set the pupil plane 5c and the incident surface of the micro fly's eye lens 7 optically conjugate. Therefore, the light that has passed through the spatial light modulator 3 is light corresponding to the light intensity distribution formed on the pupil plane 5c on the incident surface of the micro fly's eye lens 7 disposed at a position optically conjugate with the pupil plane 5c. Form an intensity distribution.

  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 operation 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 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. Note that an opening (light) having a shape corresponding to the secondary light source is located at or near the rear focal plane of the micro fly's eye lens 7, that is, at a position optically conjugate with an entrance pupil plane of the projection optical system PL described later. An illumination aperture stop having a transmission part) may be arranged.

  The light that passes through the rectangular opening (light transmitting portion) of the mask blind 9 is subjected to the light condensing action of the imaging optical system 10 and is -Z by the mirror MR3 disposed in the optical path of the imaging optical system 10. After being reflected in the direction, the mask M on which a predetermined pattern is formed is illuminated 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 of the present embodiment includes a first pupil intensity distribution measurement unit DTr that measures a pupil intensity distribution on the exit pupil plane of the illumination optical system based on light via the illumination optical system (1 to 10), and a projection optical system. A second pupil intensity distribution measurement unit DTw that measures a pupil intensity distribution on the pupil plane of the projection optical system PL (an exit pupil plane of the projection optical system PL) based on light via the PL, and first and second pupil intensity distributions And a control system CR that controls the spatial light modulator 3 based on the measurement result of at least one of the measurement units DTr and DTw and controls the overall operation of the exposure apparatus.

  The first pupil intensity distribution measurement unit DTr includes, for example, an imaging unit having a photoelectric conversion surface disposed at a position optically conjugate with the exit pupil position of the illumination optical system, and each point on the surface to be irradiated by the illumination optical system. Is monitored (pupil intensity distribution formed at the exit pupil position of the illumination optical system by light incident on each point). In addition, the second pupil intensity distribution measurement unit DTw includes an imaging unit having a photoelectric conversion surface arranged at a position optically conjugate with the pupil position of the projection optical system PL, for example, and includes each image plane of the projection optical system PL. The pupil intensity distribution related to the points (pupil intensity distribution formed by the light incident on each point at the pupil position of the projection optical system PL) is monitored.

  For the detailed configuration and operation of the first and second pupil intensity distribution measuring units DTr and DTw, reference can be made to, for example, US Patent Publication No. 2008/0030707. As the pupil intensity distribution measuring unit, the disclosure of US Patent Publication No. 2010/0020302 can be referred to.

  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. Further, the image of the formation surface of the secondary light source can be called an exit 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 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 an illumination pupil plane, and the light intensity distribution on these surfaces can also be referred to as a pupil intensity distribution. In the configuration of FIG. 1, the relay optical systems 5 and 6 and the micro fly's eye lens 7 are means for forming a pupil intensity distribution in the illumination pupil immediately after the micro fly's eye lens 7 based on the light beam that has passed through the spatial light modulator 3. It is composed.

  Next, the configuration and operation of the spatial light modulator 3 will be specifically described. As shown in FIG. 2, the spatial light modulator 3 includes a plurality of mirror elements 3a arranged in a predetermined plane, a base 3b holding the plurality of mirror elements 3a, and a cable (not shown) connected to the base 3b. ), And a drive unit 3c that individually controls and drives the postures of the plurality of mirror elements 3a. In FIG. 2, the optical path from the spatial light modulator 3 to the pupil plane 5c of the relay optical system 5 is shown.

  In the spatial light modulator 3, the attitude of the plurality of mirror elements 3a is changed by the action of the drive unit 3c that operates based on a command from the control system CR, and each mirror element 3a is set in a predetermined direction. . As shown in FIG. 3, the spatial light modulator 3 includes a plurality of minute mirror elements 3a 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. 2 and FIG. 3 show a configuration example in which the spatial light modulator 3 includes 4 × 4 = 16 mirror elements 3a. Are provided with a number of mirror elements 3a.

  Referring to FIG. 2, among the light beams incident on the spatial light modulator 3, the light beam L1 is incident on the mirror element SEa of the plurality of mirror elements 3a, and the light beam L2 is incident on the mirror element SEb different from the mirror element SEa. To do. 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 3, the optical axis AX of the optical path between the optical path bending mirror MR1 and the spatial light modulator 3 in the reference state in which the reflection surfaces of all the mirror elements 3a are set along one plane. The configuration is such that the light beam incident along the parallel direction travels in a direction parallel to the optical axis AX of the optical path between the spatial light modulator 3 and the relay optical system 5 after being reflected by the spatial light modulator 3. Has been. As described above, the array surface of the plurality of mirror elements 3a of the spatial light modulator 3 and the pupil surface 5c of the relay optical system 5 are optically positioned in a Fourier transform relationship via the front lens group 5a. ing.

  Accordingly, the light reflected by the plurality of mirror elements SEa to SEd of the spatial light modulator 3 and given a predetermined angular distribution forms the predetermined light intensity distributions SP1 to SP4 on the pupil plane 5c, 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 front lens group 5a determines the angle that the plurality of mirror elements SEa to SEd of the spatial light modulator 3 gives to the emitted light on the pupil plane 5c that is the far field (Fraunhofer diffraction region) of the spatial light modulator 3. Convert to position. Thus, the light intensity distribution (pupil intensity distribution) of the secondary light source formed by the micro fly's eye lens 7 is the light intensity formed on the incident surface of the micro fly's eye lens 7 by the spatial light modulator 3 and the relay optical systems 5 and 6. The distribution corresponds to the distribution.

  As shown in FIG. 3, the spatial light modulator 3 is a large number of minute reflecting elements regularly and two-dimensionally arranged along one plane with a planar reflecting surface as the upper surface. A movable multi-mirror including a mirror element 3a. Each mirror element 3a 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 3c that operates based on a control signal from the control system CR. Each mirror element 3a can be rotated continuously or discretely by a desired rotation angle with two directions 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 reflecting surface of each mirror element 3a.

  When the reflection surface of each mirror element 3a is discretely rotated, the rotation angle is set in a plurality of states (for example,..., -2.5 degrees, -2.0 degrees, ... 0 degrees, +0.5 degrees) ... +2.5 degrees,. Although FIG. 3 shows a mirror element 3a having a square outer shape, the outer shape of the mirror element 3a is not limited to a square. However, from the viewpoint of light utilization efficiency, the shape can be arranged so that the gap between the mirror elements 3a is reduced (a shape that can be packed most closely). Further, from the viewpoint of light utilization efficiency, the interval between two adjacent mirror elements 3a can be minimized.

  In the present embodiment, as the spatial light modulator 3, for example, a spatial light modulator that continuously changes the directions of a plurality of mirror elements 3a arranged two-dimensionally is used. As such a spatial light modulator, for example, European Patent Publication No. 779530, US Pat. No. 5,867,302, US Pat. No. 6,480,320, US Pat. No. 6,600,591 U.S. Patent No. 6,733,144, U.S. Patent No. 6,900,915, U.S. Patent No. 7,095,546, U.S. Patent No. 7,295,726, U.S. Patent No. 7, No. 424,330, U.S. Patent No. 7,567,375, U.S. Patent Publication No. 2008/0309901, U.S. Patent Publication No. 2011/0181852, U.S. Patent Publication No. 2011/188017, and JP-A-2006. The spatial light modulator disclosed in Japanese Patent Application No. 113437 can be used. Note that the orientations of the plurality of mirror elements 3a arranged two-dimensionally may be controlled to have a plurality of discrete stages.

  In the spatial light modulator 3, the attitude of the plurality of mirror elements 3a is changed by the action of the drive unit 3c that operates according to the control signal from the control system CR, and each mirror element 3a is set in a predetermined direction. The The light reflected at a predetermined angle by each of the plurality of mirror elements 3 a of the spatial light modulator 3 forms a desired pupil intensity distribution on the illumination pupil immediately after the micro fly's eye lens 7. Furthermore, the position of another illumination pupil optically conjugate with the illumination pupil immediately after the micro fly's eye lens 7, that is, the pupil position of the imaging optical system 10 and the pupil position of the projection optical system PL (the aperture stop AS is disposed). The desired pupil intensity distribution is also formed at the (position).

  As described above, the spatial light modulator 3 variably forms a pupil intensity distribution on the illumination pupil immediately after the micro fly's eye lens 7. The relay optical systems 5 and 6 are distribution forming optical systems that form an image of the far field pattern formed in the far field by the plurality of mirror elements 3a of the spatial light modulator 3 on the illumination pupil of the incident surface of the micro fly's eye lens 7. Is configured. This distribution forming optical system converts the angular distribution of the emitted light beam from the spatial light modulator 3 into a position distribution in the cross section of the emitted light beam from the distribution forming optical system.

  FIG. 4 is a diagram showing the optical path from the lens array 2a to the pupil plane 5c of the relay optical system 5 developed in a straight line. In FIG. 4, the spatial light modulator 3 is illustrated as a transmissive spatial light modulator, and the beam splitter BS and the optical path bending mirror MR1 are not illustrated. In FIG. 4, the x-axis is set in the direction perpendicular to the paper surface, the y-axis is set in the direction of the optical axis AX extending horizontally on the paper surface, and the z-axis is set in the vertical direction on the paper surface.

  The polarizing member 4 is disposed in the vicinity of the spatial light modulator 3 and in the optical path between the relay optical system 2b and the spatial light modulator 3, that is, in the optical path through which a substantially parallel light beam propagates. Hereinafter, in order to facilitate understanding of the description, a parallel light beam having a rectangular cross section whose light intensity is uniformed by the action of the light intensity distribution uniforming member 2 is incident on the polarizing member 4, and the light intensity distribution is obtained. The light passing through the homogenizing member 2 is linearly polarized light polarized in the z direction (hereinafter referred to as “z direction linearly polarized light”).

  As shown in FIG. 5, the polarizing member 4 has a half-wave plate 41 arranged in the optical path so as to act on a part of the propagating light beam propagating in the optical path. The half-wave plate 41 has, for example, a rectangular outer shape, and is arranged so that the incident surface and the emission surface thereof are orthogonal to the optical axis AX, and is movable in the z direction (also in the x direction as necessary). It is. The polarizing member 4 includes a drive unit DR41 that moves the half-wave plate 41 in the z direction. The drive unit DR41 has an actuator for moving the half-wave plate 41 and an encoder for detecting the amount of movement of the half-wave plate 41, and 1 based on a control signal from the control system CR. / The wavelength plate 41 is moved.

  As shown in FIG. 6, a z-direction linearly polarized parallel light beam F <b> 1 having a rectangular cross section centered on the optical axis AX is incident on the polarizing member 4. In this case, of the incident light beam F1, the first partial light beam F11 inside (+ z direction side) from the edge 41a of the half-wave plate 41 enters the spatial light modulator 3 via the half-wave plate 41. . The second partial light beam F12 outside (−z direction side) the edge 41a of the half-wave plate 41 is incident on the spatial light modulator 3 without passing through the half-wave plate 41. 5 and 6 show a state in which the half-wave plate 41 is arranged so as to act on the light beam propagating in the optical path in the + z direction from the xy plane including the optical axis AX.

  In the state shown in FIG. 6, the half-wave plate 41 is polarized in the x direction by rotating the z direction by +90 degrees (90 degrees clockwise in the paper of FIG. 6) when z-direction linearly polarized light is incident. The direction of the optical axis is set to a direction that forms 45 degrees with respect to the x direction and the z direction so that x-direction linearly polarized light having a direction is emitted. As a result, the light beam F1 incident on the spatial light modulator 3 immediately after the polarizing member 4 is in a polarization state as shown in FIG. That is, since the first partial light beam F11 is subjected to the polarization action of the half-wave plate 41, it becomes x-direction linearly polarized light. Since the second partial light beam F12 is not subjected to the polarization action of the half-wave plate 41, it remains the z-direction linearly polarized light.

  A partial region R11 (see FIG. 6) occupied by the first partial light beam F11 at the position of the polarizing member 4 is a partial region R01 in the effective reflection region on the arrangement surface of the spatial light modulator 3, as shown in FIG. It corresponds. Similarly, the partial region R12 (see FIG. 6) occupied by the second partial light beam F12 corresponds to the partial region R02 on the arrangement surface of the spatial light modulator 3. A rectangular region R0 circumscribing the partial regions R01 and R02 on the arrangement surface of the spatial light modulator 3 corresponds to a region R1 occupied by the incident light beam F1 at the position of the polarizing member 4 (see FIG. 6).

  As shown in FIG. 9, the driving unit 3 c of the spatial light modulator 3 transmits a pair of pupils on the pupil plane 5 c of the relay optical system 5 so that the light passing through the first mirror element group S 01 located in the first partial region R 01 The postures of the plurality of mirror elements 3a belonging to the first mirror element group S01 are controlled so as to be guided to the regions R11a and R11b. The pair of pupil regions R11a and R11b are regions that are spaced apart in the z direction with the optical axis AX interposed therebetween, for example.

  The drive unit 3c is configured so that the light that has passed through the second mirror element group S02 located in the second partial region R02 is guided to the pair of pupil regions R12a and R12b on the pupil surface 5c of the relay optical system 5. The postures of the plurality of mirror elements 3a belonging to the element group S02 are respectively controlled. The pair of pupil regions R12a and R12b are regions that are spaced apart in the x direction with the optical axis AX interposed therebetween, for example.

  Thus, the spatial light modulator 3 forms, on the pupil plane 5c of the relay optical system 5, a quadrupolar light intensity distribution 21 composed of, for example, four substantially circular surface light sources P11a, P11b; P12a, P12b. To do. That is, the first partial light beam F11 forms the surface light sources P11a and P11b occupying the pupil regions R11a and R11b through the first mirror element group S01 of the spatial light modulator 3. Since the light forming the surface light sources P11a and P11b passes through the half-wave plate 41, it is x-direction linearly polarized light.

  The second partial light beam F12 passes through the second mirror element group S02 of the spatial light modulator 3 to form surface light sources P12a and P12b occupying the pupil regions R12a and R12b. Since the light forming the surface light sources P12a and P12b does not pass through the half-wave plate 41, it is z-direction linearly polarized light. A quadrupole light intensity distribution corresponding to the light intensity distribution 21 is formed on the incident surface of the micro fly's eye lens 7.

  Thus, due to the cooperative action of the spatial light modulator 3 and the polarizing member 4, the illumination pupil immediately after the micro fly's eye lens 7 has a quadrupole and circumferentially polarized pupil intensity distribution corresponding to the light intensity distribution 21. 21 'is formed. Furthermore, the position of another illumination pupil optically conjugate with the illumination pupil immediately after the micro fly's eye lens 7, that is, the pupil position of the imaging optical system 10 and the pupil position of the projection optical system PL (the aperture stop AS is disposed). 4), a pupil intensity distribution in a circumferentially polarized state corresponding to the light intensity distribution 21 is also formed.

  The amount of light of the first partial light beam F11 whose polarization state is changed by the half-wave plate 41 varies depending on the position of the edge 41a of the half-wave plate 41 in the z direction. In other words, when the z-direction position of the half-wave plate 41 changes, the surface light sources P11a and P11b in the x-direction linear polarization state and the surface light sources P12a and P12b in the z-direction linear polarization state in the pupil intensity distribution 21 ′. The intensity ratio between them changes.

  In general, in the circumferential polarization illumination based on the annular intensity distribution in the circumferential polarization state or a multipolar (bipolar, quadrupole, octupole, etc.) pupil intensity distribution, the wafer W as the final irradiated surface is formed. The irradiated light becomes a polarization state mainly composed of s-polarized light. 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). 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 (irradiated surface: the surface of the wafer W). 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 present embodiment, since the spatial light modulator 3 having a large number of mirror elements 3a whose postures are individually controlled is used, the degree of freedom regarding the change of the polarization state of the pupil intensity distribution is high. As an example, just by controlling the spatial light modulator 3 in accordance with a command from the control system CR, as shown in FIG. 10, the illumination pupil immediately after the micro fly's eye lens 7 has a quadrupole and radially polarized pupil. An intensity distribution 22 can be formed.

  In the example shown in FIG. 10, the light that has passed through the half-wave plate 41 and the first mirror element group S01 is directed to a pair of pupil regions R21a and R21b that are spaced apart in the x direction across the optical axis AX on the illumination pupil plane. Guided to form substantial surface light sources P21a, P21b. The light that has passed through the second mirror element group S02 without passing through the half-wave plate 41 is guided to a pair of pupil regions R22a and R22b that are spaced apart in the z direction across the optical axis AX, and is substantially a surface light source. P22a and P22b are formed. In this way, a pupil intensity distribution 22 in a quadrupole and radially polarized state composed of, for example, four circular surface light sources P21a, P21b; P22a, P22b is formed on the illumination pupil immediately after the micro fly's eye lens 7. The

  In general, in radial polarization illumination based on an annular or multipolar pupil intensity distribution in the radial polarization state, the light irradiated on the wafer W as the final irradiated surface is a polarization state whose main component is p-polarization. become. Here, p-polarized light is linearly polarized light having a polarization direction in a direction parallel to the incident surface defined as described above (polarized light whose electric vector is oscillating in a direction parallel to the incident surface). is there. As a result, in the radial polarization illumination, a good mask pattern image can be obtained on the wafer (photosensitive substrate) while suppressing the reflectance of light in the resist applied to the wafer W to be small.

  The control system CR can be composed of, for example, a so-called workstation (or microcomputer) composed of a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory), and the like. The entire apparatus can be controlled in an integrated manner. The control system CR includes, for example, a storage device including a hard disk, an input device including a pointing device such as a keyboard and a mouse, a display device such as a CRT display (or liquid crystal display), a CD (compact disc), a DVD (digital). A drive device for an information storage medium such as a versatile disc (MO), a magneto-optical disc (MO), or a flexible disc (FD) may be externally connected.

  In the storage device, information on the pupil intensity distribution (illumination light source shape) at which the imaging state of the projection image projected onto the wafer W by the projection optical system PL is optimum (for example, aberration or line width is within an allowable range), The control information of the illumination optical system corresponding to the above, particularly the mirror element of the spatial light modulator 3 may be stored. An information storage medium (a CD-ROM for convenience in the following description) in which a program for setting a pupil intensity distribution, which will be described later, is stored may be set in the drive device. These programs may be installed in the storage device. The control system CR reads these programs onto the memory as appropriate.

  The control system CR can control the spatial light modulator 3 by the following procedure, for example. In the following description, it is assumed that the exposure apparatus of the embodiment forms a pupil intensity distribution 21 'shown in FIG. The pupil intensity distribution can be expressed, for example, in a format (broadly defined bitmap format) in which the pupil plane is divided into a plurality of sections in a lattice shape and expressed as numerical values using the light intensity and polarization state of each section. Here, assuming that the number of mirror elements of the spatial light modulator 3 is N and the number of divided sections of the pupil intensity distribution is M, N rays reflected by the individual mirror elements are appropriately combined to form M. A pupil intensity distribution (secondary light source) is formed (set) by appropriately superimposing N rays on M bright spots composed of M partitions. Is done.

  First, the control unit CR reads information on the target pupil intensity distribution 21 'from the storage device. Next, from the information regarding the read pupil intensity distribution 21 ′, how many light beams are required to form an intensity distribution for each polarization state is calculated. Then, the control unit CR virtually divides the plurality of mirror elements of the spatial light modulator 3 into two mirror element groups S01 and S02 each including a required number of mirror elements, and each mirror element group S01 and S02. The partial regions R01 and R02 in which are located and the partial regions R11 and R12 corresponding to these partial regions are set.

  The controller CR drives the half-wave plate 41 of the polarizing member 4 to position the half-wave plate 41 so as to cover the region corresponding to the partial region R11. Further, the controller CR drives the mirror element 3a of the first mirror element group S01, and sets the light from the first mirror element group S01 to face the surface light sources P11a and P11b. Similarly, the mirror element 3a of the second mirror element group S02 is driven so that the light from the second mirror element group S02 is directed toward the surface light sources P12a and P12b.

  In the present embodiment, since the spatial light modulator 3 having a large number of mirror elements 3a whose postures are individually controlled is provided, freedom in changing the shape (wide concept including size) of the pupil intensity distribution and the polarization state. The degree is high. In the present embodiment, the polarization member 4 disposed in the vicinity of the arrangement surface of the spatial light modulator 3 and the light intensity distribution uniformization that improves the uniformity of the intensity distribution of the light incident on the spatial light modulator 3. Since the member 2 is provided, the controllability of the spatial light modulator 3 can be improved, and the desired polarization state of the pupil intensity distribution can be realized with high accuracy.

  In the present embodiment, light having a non-uniform beam profile emitted from the light source LS becomes light whose intensity distribution is improved by the action of the light intensity distribution uniforming member 2, and the spatial light modulator 3 Incident on the array surface. That is, by the action of the light intensity distribution uniforming member 2, the light intensity distribution of the light beam incident on each mirror element 3a of the spatial light modulator 3 is made uniform, and consequently the light intensity distribution of the light beam emitted from each mirror element 3a. Is also made uniform. As a result, the controllability of the spatial light modulator 3 to drive a large number of mirror elements 3a when forming the pupil intensity distribution is improved.

  In addition, since the light intensity distribution of the light beam incident on the polarizing member 4 is made uniform by the action of the light intensity distribution uniforming member 2, the z-direction position of the half-wave plate 41 and the polarization state by the half-wave plate 41. The relationship with the light quantity of the first partial light beam F11 to be changed becomes linear and simplified. As a result, by changing the z-direction position of the half-wave plate 41, for example, surface light sources P11a and P11b in the x-direction linear polarization state and surface light sources P12a and P12b in the z-direction linear polarization state in the pupil intensity distribution 21 ′ The intensity ratio between the two can be adjusted, so that the desired polarization state of the pupil intensity distribution 21 'can be realized with high accuracy.

  Further, the monitoring result of the light intensity distribution on the arrangement surface of the spatial light modulator 3 is supplied from the beam monitor BM to the control unit CR as necessary. In this case, the control unit CR refers to the monitoring result regarding the light intensity distribution of the beam monitor BM as needed, and appropriately controls the spatial light modulator 3 according to the temporal variation of the beam profile of the light supplied from the light source LS. Thus, a desired pupil intensity distribution can be stably formed.

  As described above, in the illumination optical system (1 to 10) of the present embodiment, the controllability of the spatial light modulator 3 can be improved, and as a result, a desired polarization state of the pupil intensity distribution can be realized with high accuracy. it can. In the exposure apparatus (1 to WS) of this embodiment, the illumination optical system (1 to 10) that accurately realizes a desired polarization state of the pupil intensity distribution is used according to the pattern characteristics of the mask M to be transferred. The fine pattern can be accurately transferred onto the wafer W under the appropriate illumination conditions realized.

  In the above description, the polarizing member 4 including the single half-wave plate 41 is disposed in the vicinity of the arrangement surface of the spatial light modulator 3. However, the present invention is not limited to this, and various forms are possible for the form, number, arrangement, and the like of the polarizing elements constituting the polarizing member 4. For example, as shown in FIG. 11, a hexapole pupil intensity distribution using a polarizing member 4 provided with a pair of half-wave plates 42 and 43 arranged in the vicinity of the arrangement surface of the spatial light modulator 3. Can be formed. In the modification of FIG. 11, a pair of half-wave plates 42 and 43 having different polarization conversion characteristics and movable in the z direction are arranged in parallel.

  When the z-direction linearly polarized light is incident, the half-wave plate 42 rotates the z direction by +60 degrees (60 degrees clockwise in the plane of FIG. 11) and has a polarization direction in a diagonal direction of +60 degrees. The direction of the optical axis is set so as to emit obliquely linearly polarized light. When the z-direction linearly polarized light is incident, the half-wave plate 43 rotates the z direction by −60 degrees (60 degrees counterclockwise on the paper surface of FIG. 11) and changes the polarization direction in the oblique direction by −60 degrees. The direction of the optical axis is set so as to emit light having -60 degrees obliquely linearly polarized light.

  As a result, the light beam F1 incident on the spatial light modulator 3 immediately after the polarizing member 4 is in a polarization state as shown in FIG. That is, in the incident light beam F1, the first partial light beam F11 on the inner side (+ z direction side) of the edge 42a of the half-wave plate 42 is subjected to the polarization action of the half-wave plate 42. It becomes linearly polarized light. Since the second partial light beam F12 on the inner side (−z direction side) than the edge 43a of the half-wave plate 43 is subjected to the polarization action of the half-wave plate 43, the second partial light beam F12 becomes −60 degrees obliquely linearly polarized light. Since the third partial light beam F13 between the edges 42a and 43a is not subjected to the polarization action of the half-wave plates 42 and 43, it remains the z-direction linearly polarized light.

  A partial region R11 (see FIG. 11) occupied by the first partial light beam F11 at the position of the polarizing member 4 is a partial region R01 in the effective reflection region on the arrangement surface of the spatial light modulator 3, as shown in FIG. It corresponds. Similarly, the partial regions R12 and R13 (see FIG. 11) occupied by the partial light beams F12 and F13 correspond to the partial regions R02 and R03 on the arrangement surface of the spatial light modulator 3. A rectangular region R0 circumscribing the partial regions R01 to R03 on the arrangement surface of the spatial light modulator 3 corresponds to a region R1 occupied by the incident light beam F1 at the position of the polarizing member 4 (see FIG. 11).

  As shown in FIG. 14, the drive unit 3c of the spatial light modulator 3 receives a pair of pupils on the pupil plane 5c of the relay optical system 5 as the light that has passed through the first mirror element group S01 located in the first partial region R01. The postures of the plurality of mirror elements 3a belonging to the first mirror element group S01 are controlled so as to be guided to the regions R31a and R31b. The pair of pupil regions R31a and R31b are regions that are spaced apart in a diagonal direction by −30 degrees across the optical axis AX, for example.

  The drive unit 3c is configured so that the light that has passed through the second mirror element group S02 located in the second partial region R02 is guided to the pair of pupil regions R32a and R32b on the pupil surface 5c of the relay optical system 5. The postures of the plurality of mirror elements 3a belonging to the element group S02 are respectively controlled. The pair of pupil regions R32a and R32b are regions that are spaced apart by an angle of +30 degrees with the optical axis AX interposed therebetween, for example.

  The drive unit 3c is configured so that the light that has passed through the third mirror element group S03 located in the third partial region R03 is guided to the pair of pupil regions R33a and R33b on the pupil plane 5c of the relay optical system 5. The postures of the plurality of mirror elements 3a belonging to the element group S03 are respectively controlled. The pair of pupil regions R33a and R33b are regions that are spaced apart in the x direction with the optical axis AX interposed therebetween, for example.

  In this way, the spatial light modulator 3 has, for example, six polar light intensities formed on the pupil plane 5c of the relay optical system 5 including, for example, six substantially circular surface light sources P31a and P31b; P32a and P32b; P33a and P33b. A distribution 23 is formed. That is, the first partial light beam F11 forms the surface light sources P31a and P31b occupying the pupil regions R31a and R31b through the first mirror element group S01 of the spatial light modulator 3. Since the light that forms the surface light sources P31a and P31b passes through the half-wave plate 42, it is +60 degrees oblique linearly polarized light.

  The second partial light beam F12 passes through the second mirror element group S02 of the spatial light modulator 3 to form surface light sources P32a and P32b occupying the pupil regions R32a and R32b. Since the light that forms the surface light sources P32a and P32b passes through the half-wave plate 43, it is -60 degrees oblique linearly polarized light. The third partial light beam F13 passes through the third mirror element group S03 of the spatial light modulator 3 to form surface light sources P33a and P33b occupying the pupil regions R33a and R33b. Since the light forming the surface light sources P33a and P33b does not pass through the half-wave plates 42 and 43, it is z-direction linearly polarized light.

  In this way, a pupil intensity distribution 23 ′ having a hexapolar and circumferentially polarized state corresponding to the light intensity distribution 23 is formed on the illumination pupil immediately after the micro fly's eye lens 7. In the modification of FIG. 11, by changing the z-direction positions of the half-wave plates 42 and 43, the surface light sources P31a, P31b and P32a, P32b, P33a, and P33b having different polarization states in the pupil intensity distribution 23 ′. The intensity ratio between the two can be adjusted.

  Although not shown in the drawings, a pupil intensity distribution in a hexapolar and radially polarized state can be formed using a polarizing member having a pair of half-wave plates having different polarization conversion characteristics. Although not shown in the drawings, a pupil member having, for example, an octupole and a circumferential polarization state (or a radial polarization state) using a polarization member having three half-wave plates having different polarization conversion characteristics is used. A distribution can be formed.

  In the above description, as the polarizing member, one or a plurality of half-wave plates arranged in the optical path along which a part of the propagating light beam travels are used. However, the light is not limited to a half-wave plate, and is polarized using, for example, one or a plurality of quarter-wave plates, an optical rotator, or the like arranged in an optical path along which a part of the propagating light beam travels. A member can also be comprised. When a polarizing member provided with a ¼ wavelength plate is used, the polarization state of an arbitrary surface light source in the pupil intensity distribution can be set to a desired elliptically polarized light.

  The optical rotator has the form of a plane-parallel plate and is formed of a crystal material, for example, quartz, which is an optical material having optical activity. The optical rotator is arranged such that the incident surface (and hence the exit surface) is orthogonal to the optical axis AX, and the crystal optical axis is substantially coincident with the direction of the optical axis AX (that is, substantially coincident with the traveling direction of incident light). Is done. When a polarizing member having an optical rotator is used, the polarization state of an arbitrary surface light source in the pupil intensity distribution can be set to a desired linearly polarized light.

  In the above description, the polarizing member 4 is disposed in the vicinity of the arrangement surface of the spatial light modulator 3. However, the present invention is not limited to this, and as shown by a broken line in FIG. 1, a position substantially optically conjugate with the arrangement surface of the spatial light modulator 3 in the optical path closer to the irradiated surface than the spatial light modulator 3. The polarizing member 4 can be disposed on the surface. Although not shown, the polarizing member may be disposed at a position optically conjugate with the arrangement surface of the spatial light modulator in the optical path closer to the light source than the spatial light modulator.

  In general, the polarizing member may be arranged at a position near the arrangement surface of the spatial light modulator or in a conjugate space including a surface optically conjugate with the arrangement surface of the spatial light modulator. Here, the “conjugate space” means an optical element having power adjacent to the front side of the conjugate position optically conjugate with the arrangement surface of the spatial light modulator and an optical element having power adjacent to the rear side of the conjugate position. It is a space between. In the “conjugate space”, there may be a parallel plane plate or a plane mirror having no power.

  In the above description, the light intensity distribution uniformizing member that is arranged in the optical path between the light source LS and the spatial light modulator 3 and improves the uniformity of the intensity distribution of light incident on the array surface of the spatial light modulator 3. 2, a lens array 2a as a wavefront splitting element and a relay optical system 2b are used. However, the light intensity distribution uniforming member can be configured using, for example, an internal reflection type optical integrator (typically, a rod type integrator).

  In the light intensity distribution uniforming member, it is important that the uniformity of the light intensity distribution of the light beam emitted from the member is better than the uniformity of the light intensity distribution of the light beam incident on the member. The light intensity distribution of the light beam emitted from the member may not be completely uniform. The light intensity distribution uniformizing member can be disposed closer to the light source than the intermediate position of the optical path between the light source and the spatial light modulator.

  The light intensity distribution uniformizing member 2 is disposed on the light source side of the polarizing member 4 in the optical path between the light source LS and the spatial light modulator 3. When the polarizing member is disposed closer to the light source than the light intensity distribution uniforming member, a plurality of light beams having different polarization states generated by the polarizing member are wavefront-divided into a larger number of light beams through the light intensity distribution uniforming member. Lights having different polarization states are mixed in each mirror element of the optical modulator, and as a result, a pupil intensity distribution having a desired polarization state cannot be formed.

  In the above-described embodiment, as the spatial light modulator having a plurality of mirror elements that are two-dimensionally arranged and individually controlled, the directions (angle: inclination) of the plurality of two-dimensionally arranged reflecting surfaces are individually set. The controllable spatial light modulator 3 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. The spatial light modulator having a plurality of reflection surfaces arranged two-dimensionally as described above is modified in accordance with the disclosure of, for example, US Pat. No. 6,891,655 and US Patent Publication No. 2005/0095749. May be.

  In the above-described embodiment, the spatial light modulator 3 includes a plurality of mirror elements 3a that are two-dimensionally arranged in a predetermined plane. However, the present invention is not limited to this, and the spatial light modulator 3 is arranged in a predetermined plane and individually. It is also possible to use a transmissive spatial light modulator including a plurality of transmissive optical elements controlled by the above.

  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. As the variable pattern forming apparatus, for example, a spatial light modulation element including a plurality of reflection elements driven based on predetermined electronic data can be used. An exposure apparatus using a spatial light modulator is disclosed, for example, in US Patent Publication No. 2007/0296936. In addition to the non-light-emitting reflective spatial light modulator as described above, a transmissive spatial light modulator may be used, or a self-luminous image display element may be used.

  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 Beam transmitter 2 Light intensity distribution uniform member 3 Spatial light modulator 4 1/2 wavelength plate (polarizing member)
5,6 Relay optical system 7 Micro fly's eye lens (optical integrator)
8 Condenser optical system 9 Mask blind 10 Imaging optical system LS Light source DTr, DTw Pupil intensity distribution measuring unit CR Control system M Mask MS Mask stage PL Projection optical system W Wafer WS Wafer stage

Claims (1)

In the illumination optical system that illuminates the illuminated surface with the illumination light from the light source through the illumination pupil,
A first optical system for making the intensity distribution of illumination light from the light source uniform;
A polarization unit that changes a polarization state of at least a part of the illumination light in which the intensity distribution from the first optical system is made uniform;
A second optical system having a plurality of reflecting surfaces for reflecting the illumination light from the polarizing unit, and individually controlling the plurality of reflecting surfaces to distribute the illumination light to the illumination pupil;
A beam detection system that detects an angle of light traveling from the first optical system toward the polarization unit;
An illumination optical system.

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