JP5953657B2 - Spatial light modulator, exposure apparatus, and device manufacturing method - Google Patents

Description

  The present invention relates to a spatial light modulator having a plurality of reflecting elements, an exposure technique for exposing an object using the spatial light modulator, and a device manufacturing technique using the exposure technique.

For example, in a lithography process for manufacturing a device (electronic device or microdevice) such as a semiconductor element or a liquid crystal display element, a predetermined pattern is formed on a substrate such as a wafer or a glass plate via a projection optical system. A batch exposure type exposure apparatus such as a stepper or a scanning exposure type exposure apparatus such as a scanning stepper is used.
Recently, in order to suppress the increase in manufacturing cost by preparing a mask for each of a plurality of types of devices and each of a plurality of layers of a substrate, and to efficiently manufacture each device, A so-called maskless exposure apparatus that generates a variable pattern on the object plane of a projection optical system using spatial light modulators having an array of micromirrors with variable rotation angles (tilt angles) Has been proposed. In addition, as a spatial light modulator, there is a type that has an array of a large number of square micromirrors each having a variable rotation angle and a step in the center, and can control the phase distribution of incident light substantially. It has been proposed (see Non-Patent Document 1, for example). By controlling the phase distribution of incident light in this way, a variable phase pattern can be generated on the object plane of the projection optical system.

Hans Martinsson et al., “Current status of optical masklesslithography,” J. Microlith., Microfab., Microsyst. Vol. 4 (1), 011003-1 to -15, SPIE (USA) (2005)

When a conventional spatial light modulator that controls the phase of reflected light by controlling the rotation angle of a square micromirror provided with a step is used, there is a problem that the intensity of the reflected light is small. In addition, particularly when the size of the micromirror is reduced, there is a problem that the difference in reflectance depending on the polarization direction of incident light increases.
In view of such circumstances, the aspect of the present invention increases the intensity of reflected light when using a spatial light modulator having an array of a plurality of reflecting elements, or the difference in reflectance depending on the polarization direction of incident light. The purpose is to make it smaller.

According to a first aspect of the invention, a spatial light modulator having an array of a plurality of reflective elements is provided. In the spatial light modulator, the first and second reflecting elements among the plurality of reflecting elements are respectively supported so as to be rotatable around the first rotation axis, and the first and second reflecting elements among the plurality of reflecting elements are supported. A third reflective element different from the second reflective element is supported rotatably about a second rotational axis parallel to the first rotational axis, and the first and second reflective elements of the plurality of reflective elements. The elements are each at a first distance from the first rotation axis and having a first width in a direction parallel to the first rotation axis, and the first distance from the first rotation axis. A second reflecting portion including a second portion having a second width wider than the first width in a direction parallel to the first rotation axis and at a second distance that is further away its third reflective elements of the reflective elements, the third from the second rotary shaft to the first rotating shaft side Situated, and a third portion in the direction parallel to the second rotation shaft having a third width, a fourth apart than THEREOF third distance from the second axis of rotation to the first rotating shaft side And a second portion including a fourth portion having a fourth width wider than the third width in a direction parallel to the second rotation axis and the first reflective element The first reflection portion of the first reflection portion and the first reflection portion of the second reflection element are disposed on the second rotation axis side of the first rotation axis, and the first portion of the first reflection element The fourth portion of the third reflective element is located between the first portion of the second reflective element.
According to another aspect, a spatial light modulator having an array of a plurality of reflective elements is provided. In the spatial light modulator, the reflective element is supported rotatably about the rotation axis, and the reflective element is at a first distance from the rotation axis and in a direction parallel to the rotation axis. A first portion having a first width and a second width that is at a second distance away from the first axis from the rotation axis and that is wider than the first width in a direction parallel to the rotation axis And a second reflection portion including the second reflection portion.

  Moreover, according to the 2nd aspect, the spatial light modulator which has an array of the some reflective element which each irradiates light is provided. In this spatial light modulator, the plurality of reflective elements are supported so as to be rotatable about a rotation axis, respectively, and the plurality of reflective elements intersect with the rotation axis by more than 0 ° and less than 90 °. It is installed at a position where illumination light polarized in a direction intersecting at an angle is irradiated.

  Moreover, according to the 3rd aspect, the exposure apparatus which exposes a board | substrate via a projection optical system with exposure light is provided. The exposure apparatus includes the spatial light modulator of the present invention disposed on the object plane side of the projection optical system, and an illumination system that illuminates the plurality of reflective elements of the spatial light modulator with the exposure light. The substrate is exposed through the projection optical system by the exposure light from the plurality of reflecting elements of the spatial light modulator.

  According to a fourth aspect, there is provided a device manufacturing method comprising: forming a pattern of a photosensitive layer on a substrate using the exposure apparatus of the present invention; and processing the substrate on which the pattern is formed. Is provided.

According to the first aspect of the present invention, since the first reflecting portion of the reflecting element includes a portion whose width (area) increases as the distance from the rotation axis increases, the rotation angle of the reflecting element is controlled. When controlling the phase of the reflected light, the intensity of the reflected light increases.
Further, according to the second aspect of the present invention, the reflecting element is installed at a position where illumination light polarized in a direction intersecting at a crossing angle larger than 0 ° and smaller than 90 ° with respect to the rotation axis is irradiated. Therefore, when the phase of the reflected light is controlled by controlling the rotation angle of the reflecting element, the polarization of the incident light is compared to the case where the polarization direction of the incident light intersects the rotation axis at 0 ° or 90 °. The difference in reflectance depending on the direction is reduced.

It is a figure which shows schematic structure of the exposure apparatus of an example of embodiment. (A) is an enlarged view showing a part of the spatial light modulator 28 of the first embodiment, and (B) is an enlarged view showing a mirror element 30 in FIG. 2 (A). (A) is an enlarged perspective view showing a part of the array of mirror elements 30 in FIG. 2 (A), and (B) and (C) are views of the mirror element 30 in FIG. 3 (A) along the line BB. FIG. (A) is a diagram showing a state in which the mirror element 30 is rotated clockwise, (B) is a diagram showing a phase distribution of reflected light corresponding to FIG. 4 (A), and (C) is a counterclockwise rotation of the mirror element 30. FIG. 4D is a diagram showing a phase distribution of reflected light corresponding to FIG. 4C. (A) is a diagram showing a state in which a flat mirror element is rotated clockwise, (B) is a diagram showing a phase distribution of reflected light corresponding to FIG. The figure which shows the state rotated clockwise, (D) is a figure which shows phase distribution of the reflected light corresponding to FIG.5 (C). (A) is a view showing a shot area of a wafer at the time of scanning exposure, and (B) is a view showing a shot area of the wafer at the time of exposure by the step-and-repeat method. It is an expansion perspective view which shows the mirror element of a comparative example. (A) is a figure which shows an example of the relationship between the rotation angle (phase conversion value) of the mirror element of various spatial light modulators, and the electric field amplitude of reflected light, (B) is the reflected light corresponding to FIG. 8 (A). It is a figure which shows the intensity | strength of. (A), (B), (C) is a diagram showing the reflectance of the mirror element when the incident light is random polarized light, X polarized light, and Y polarized light, respectively, and (D) is a case where the polarized light of the incident light is not taken into consideration. It is a figure which shows the reflectance of the mirror element. (A) is an enlarged view showing the phase distribution of reflected light used in the simulation, (B) is a diagram showing a resist pattern corresponding to the phase distribution of FIG. 10 (A), and (C) is the reflected light of the comparative example. An enlarged view showing the phase distribution, (D) is a view showing a resist pattern of a comparative example. (A) is an enlarged view showing a resist pattern obtained by simulation, and (B) is a view showing a light intensity distribution in the central cross section of FIG. 11 (A). It is a figure which shows the relationship between the rotation angle (phase conversion value) of a mirror element, and the intensity | strength of reflected light. (A) is an enlarged view showing an example of a phase pattern, (B) is a diagram showing a resist pattern corresponding to the phase pattern, (C) is a diagram showing an inverted phase pattern, and (D) is an inverted phase pattern. (E) is a figure which shows the resist pattern after double exposure. (A) is an enlarged perspective view showing the principal part of the spatial light modulator of the first modification, and (B) is an enlarged perspective view showing the principal part of the spatial light modulator of the second modification. (A) is an enlarged view showing a part of the spatial light modulator 28A of the third modified example, and (B) is an enlarged view showing a mirror element 30A in FIG. 15 (A). (A) is an enlarged perspective view showing a part of the array of mirror elements 30A in FIG. 15 (A), and (B) is a view of the mirror elements 30A in FIG. 16 (A) taken along line BB. (A) is a figure which shows an example of the relationship between the rotation angle (phase conversion value) of 30 A of mirror elements, and the intensity | strength of reflected light, (B) is the parameter R which prescribes | regulates the shape of 30 A of mirror elements, and FIG. It is a figure which shows the relationship with the maximum value of the intensity | strength of reflected light. FIG. 19A is an enlarged view showing the phase distribution of reflected light used in the simulation, and FIG. 19B is a diagram showing a resist pattern corresponding to the phase distribution of FIG. (A) is an enlarged view showing a part of the spatial light modulator 28B of the second embodiment, and (B) is an enlarged view showing a mirror element 30B in FIG. 19 (A). FIG. 20A is an enlarged perspective view showing the mirror element 30B of FIG. 19A, and FIG. 20B is a view of the mirror element 30B of FIG. It is a figure which shows the exposure apparatus of the other example of embodiment. It is a flowchart which shows an example of the manufacturing process of an electronic device.

[First Embodiment]
Hereinafter, the first embodiment will be described with reference to FIGS.
FIG. 1 shows a schematic configuration of a maskless exposure apparatus EX of the present embodiment. In FIG. 1, an exposure apparatus EX includes an exposure light source 2 that emits pulsed light, an illumination optical system ILS that illuminates a surface to be irradiated with exposure illumination light (exposure light) IL from the light source 2, and an illumination light system ILS. A micro of a predetermined shape having a step portion 31C (see FIG. 3A) having a predetermined height and a variable rotation angle (inclination angle) arranged in a two-dimensional array on the irradiation surface or a surface in the vicinity thereof. A spatial light modulator 28 for generating a mask pattern having a large number of mirror elements 30 as mirrors, and a modulation control unit 48 for driving the spatial light modulator 28 are provided. Further, the exposure apparatus EX receives the illumination light IL reflected by the reflective variable uneven pattern (mask pattern having a variable phase distribution) generated by the multiple mirror elements 30, and the uneven pattern (phase) Projection optical system PL for projecting an aerial image (device pattern) formed corresponding to the distribution) onto the surface of wafer W (substrate), wafer stage WST for positioning and moving wafer W, and the operation of the entire apparatus. A main control system 40 composed of a computer for overall control and various control systems are provided.

  Hereinafter, in FIG. 1, a Z-axis is set perpendicular to the bottom surface of wafer stage WST (a surface parallel to a guide surface not shown), and Y-axis is set in a direction parallel to the plane of FIG. 1 in a plane perpendicular to the Z-axis. Will be described with the X axis set in the direction perpendicular to the paper surface of FIG. In addition, the angles around the X axis, the Y axis, and the Z axis are also called angles in the θx direction, the θy direction, and the θz direction, respectively. In the present embodiment, the optical axis AX of the projection optical system PL is parallel to the Z axis, and the wafer W is scanned in the Y direction (scanning direction) during exposure.

  As the light source 2, an ArF excimer laser light source is used that emits a pulse of substantially linearly polarized laser light having a wavelength of 193 nm and a pulse width of about 50 ns at a frequency of about 4 to 6 kHz. As the light source 2, a KrF excimer laser light source having a wavelength of 248 nm, a pulsed light emitting diode, or a solid pulse laser light source that generates harmonics of laser light output from a YAG laser or a solid state laser (semiconductor laser, etc.) Can be used. The solid-state pulse laser light source can emit laser light with a wavelength of 193 nm (various wavelengths other than this) and a pulse width of about 1 ns at a frequency of about 1 to 2 MHz.

In the present embodiment, a power source unit 42 is connected to the light source 2. The main control system 40 supplies a light emission trigger pulse TP instructing the pulse emission timing and the light amount (pulse energy) to the power supply unit 42. In synchronization with the light emission trigger pulse TP, the power supply unit 42 causes the light source 2 to emit pulses at the instructed timing and light quantity.
Illumination light IL made up of pulse laser light having a rectangular cross-sectional shape emitted from the light source 2 and a substantially parallel light beam is a beam expander 4 made up of a pair of lenses, and a polarization control optical system 6 that controls the polarization state of the illumination light IL. Then, the light enters the array of a large number of minute mirror elements 11 of the spatial light modulator 10 for the illumination system via the mirror 8A. The polarization control optical system 6 includes, for example, a half-wave plate that rotates the polarization direction of the illumination light IL, a quarter-wave plate for converting the illumination light IL into circularly polarized light, and the illumination light IL that is randomly polarized (non-polarized light). This is an optical system in which a wedge-shaped birefringent prism or the like for conversion into (1) can be installed interchangeably.

  A large number of mirror elements 11 of the spatial light modulator 10 are arranged in a two-dimensional array on a plane inclined in the θx direction with respect to the XY plane, and rotation angles (inclination angles) about two orthogonal axes are arranged. It is variable. The spatial light modulator 10 includes a drive unit 12 that drives each mirror element 11, and the main control system 40 controls the rotation angles of a large number of mirror elements 11 via the modulation control unit 49 and the drive unit 12. In this case, by controlling the rotation angles of the many mirror elements 11 about the two axes, the angular distribution of the illumination light IL, and hence the light quantity distribution on the pupil plane of the illumination optical system ILS, can be changed into a circular or circular pattern for normal illumination. It can be controlled to an arbitrary distribution such as a ring shape for band illumination and a dipole or quadrupole shape for multipole illumination.

  Examples of the spatial light modulator 10 include a space disclosed in, for example, US Pat. No. 6,900,915, US Pat. No. 7,095,546, or US Patent Publication No. 2005/0095749. An optical modulator can be used. Instead of the spatial light modulator 10 for the illumination system, a plurality of replaceable diffractive optical elements (DOEs) may be used.

  The illumination light IL reflected by the spatial light modulator 10 is guided to the incident surface of the microlens array 16 along the Y axis (optical axis AXI) via the relay optical system 14 including the lenses 14a and 14b and the mirror 8B. . The illumination light IL incident on the microlens array 16 is two-dimensionally divided (wavefront division) by a large number of minute lens elements constituting the microlens array 16, and the illumination optical system that is the rear focal plane of each lens element. A secondary light source (surface light source) is formed on the pupil surface of the ILS (hereinafter referred to as illumination pupil surface IPP). Note that a fly-eye lens or the like can be used instead of the microlens array 16.

  The illumination light IL from the secondary light source formed on the illumination pupil plane IPP is incident on the half mirror 24 via the first relay lens 18A, the field stop 20, the second relay lens 18B, and the condenser optical system 22, Illumination light IL reflected by the mirror 24 in the + Z direction is incident on an irradiated surface (a surface on which a designed transfer pattern is arranged) parallel to the XY plane. Reflecting surfaces of a large number of mirror elements 30 arranged in a two-dimensional array of spatial light modulators 28 are arranged on the irradiated surface or in the vicinity thereof. An illumination optical system ILS is configured including optical members from the beam expander 4 to the condenser optical system 24. As an example, the illumination light IL from the illumination optical system ILS illuminates a rectangular illumination area 26A elongated in the X direction on the array of a large number of mirror elements 30 of the spatial light modulator 28 with a substantially uniform illumination distribution. A large number of mirror elements 30 are arranged on the surface of the base member 32 of the spatial light modulator 28 in a rectangular region including the illumination region 26A at a predetermined pitch in the X direction and the Y direction. The illumination optical system ILS, the half mirror 24, and the spatial light modulator 28 are supported by a frame (not shown).

  2A is an enlarged bottom view showing a part of the reflection surface of the spatial light modulator 28 in FIG. 1, and FIG. 2B is a reflection surface parallel to the XY plane in FIG. 2A. FIG. 6 is an enlarged view showing the mirror element 30 in a simple state (in the present embodiment, a state in the center of the rotatable range). In FIG. 2B, the mirror element 30 is rotatable around a rotation axis RC parallel to the V direction that intersects the X axis and the Y axis at 45 °. The direction orthogonal to the V direction is defined as the U direction. In addition, the mirror element 30 includes a first reflecting portion 31A having a triangular plate shape having two sides substantially parallel to the X axis and the Y axis and having one apex on the rotation axis RC side, and a first reflection with respect to the rotation axis RC. A stepped portion 31C in a plane including the rotation axis RC is provided between the first reflecting portion 31A and the second reflecting portion 31B. Is formed. In the present embodiment, the height of the first reflecting portion 31A is set higher than the height of the second reflecting portion 31B. In FIG. 2A and the like, the second reflecting portion 31B having a low height is hatched. Further, the width in the V direction and the length in the U direction of the mirror element 30 are substantially the same, and the step portion 31C is parallel to the V direction. The width in the V direction and the length in the U direction of the mirror element 30 are, for example, about 1 to 10 μm.

  In the present embodiment, the surface of the wafer W includes a pattern including a line pattern parallel to the X axis, for example, a Y-direction line and space pattern (hereinafter referred to as an L & S pattern) in which the pattern is periodically arranged in the Y direction. .), Or a pattern including a line pattern parallel to the Y-axis, for example, an L & S pattern in the X direction in which the pattern is periodically arranged in the X direction is often formed. In this way, when a pattern (resist pattern) including a line pattern parallel to the X axis or Y axis is formed on the surface of the wafer W, as an example, the illumination light IL is polarized in the polarization direction PX or Y axis parallel to the X axis, respectively. Is set to linearly polarized light having a polarization direction PY parallel to the. In this case, in this embodiment, the direction (V direction) of the step portion 31C of the mirror element 30 intersects the polarization directions PX and PY at 45 °.

As shown in FIG. 2A, the many mirror elements 30 are arranged close to each other in the X direction and the Y direction so that there is almost no gap as a whole. Therefore, even if the reflecting portions 31A and 31B of the individual mirror elements 30 are triangular, the utilization efficiency of the illumination light IL is high.
3A shows three mirror elements 30 of the spatial light modulator 28 in FIG. 2A, and FIGS. 3B and 3C are parallel to the U direction in FIG. 3A. 1 shows one mirror element 30 viewed along line BB. In FIG. 3A, each mirror element 30 is supported on the surface of the base member 32 by a support driving unit 34. As an example, the support drive unit 34 is a flexible member provided in parallel with the V direction on the upper portions of the two support units 36A and 36B and the support units 36A and 36B that are disposed apart from each other in the V direction on the surface of the base member 32. And a connecting portion 35A that is provided at the center of the hinge portion 35B and supports the center of the mirror element 30. In this case, the center of the hinge portion 35B is substantially the rotation axis RC.

  In FIG. 3 (B), the base member 32 is composed of a flat substrate 32A made of, for example, silicon, and an insulating layer 32B made of silicon nitride (eg, Si3N4) formed on the surface of the substrate 32A. . Further, the mirror element 30 and the support driving unit 34 are integrally formed from, for example, polysilicon. A reflective film (not shown) made of a thin film of metal (for example, aluminum) is formed on the reflective surface (surface) of the mirror element 30 in order to increase the reflectance.

When the wavelength of the illumination light is λ, the step d1 of the step portion 31C of the mirror element 30 is set to λ / 4 as follows.
d1 = λ / 4 (1)
Accordingly, when the reflection surface of the mirror element 30 is parallel to the XY plane, the second reflection is performed with the amount of change in the phase of the illumination light IL1 incident and reflected perpendicularly to the first reflection portion 31A as the first phase difference. When the amount of change in the phase of the illumination light IL2 that is perpendicularly incident on and reflected from the part 31B is the second phase difference, the second phase difference is 180 ° (π (rad)) from the first phase difference. Is different.

  Further, electrodes 37A and 37B are formed on the bottom surfaces of the reflecting portions 31A and 31B of the mirror element 30, respectively, and electrodes 37C and 37D are formed on the surface of the base member 32 so as to face the electrodes 37A and 37B, respectively. A signal line (not shown) for applying a predetermined voltage between the electrodes 37A and 37C and between the electrodes 37B and 37D corresponding to each mirror element 30 is formed in a matrix on the surface of the base member 32 and the support driving unit 34. Is provided. In FIG. 3C, the mirror element 30 of the present embodiment is in a first state indicated by a dotted line rotated clockwise by a predetermined angle α around the rotation axis RC, or counterclockwise around the rotation axis RC. Is set to one of the second states indicated by a solid line rotated by an angle α (−α clockwise). The spatial light modulator 28 having such a minute three-dimensional structure can be manufactured using, for example, MEMS (Microelectromechanical Systems) technology. Since each mirror element 30 of the spatial light modulator 28 only needs to be set to the first state or the second state by rotation around one rotation axis RC, the mirror element 30 can be downsized and the mirror element 30 can be reduced. It is easy to increase the number of sequences.

  Here, the state of the reflected light when the mirror element 30 with a step is rotated will be described. 4A and 4C conceptually show the state in which the mirror element 30 is rotated clockwise and counterclockwise, respectively. For simplicity, it is assumed that the rotation axis RC is at the center of the step portion 31C in FIG. 3B and the origin of the position in the U direction is on the rotation axis RC. 4A and 4C, the amount of change in the phase of the reflected light at the origin of the first reflecting portion 31A is π / 2, and the amount of change in the phase of the reflected light at the origin of the second reflecting portion 31B. Is π / 2. In this case, the complex amplitudes of the reflected light from the reflecting portions 31A and 31B in FIG. 4A are symmetrical with respect to the real axis Re in the first quadrant area BA1 and the fourth quadrant area BB1 in FIG. 4B, respectively. Distributed. Therefore, the average complex amplitude of the reflected light from the entire mirror element 30 in FIG. 4A cancels the value of the imaginary axis Im on the left and right sides (reflecting portions 31A and 31B). It becomes a positive value A1a on the real axis Re. This positive value A1a means that the average phase change amount of the reflected light is zero.

  On the other hand, the complex amplitudes of the reflected light from the reflecting portions 31A and 31B in FIG. 4C are distributed symmetrically with respect to the real axis Re in the second quadrant area BA2 and the third quadrant area BB2 in FIG. 4D, respectively. To do. Therefore, the average complex amplitude of the reflected light from the entire mirror element 30 in FIG. 4C is equal to the negative value A2a on the real axis Re in FIG. Become. This negative value A2a means that the average phase change amount of the reflected light is π (180 °). In other words, the stepped mirror element 30 substantially rotates the phase of incident light in the same manner as a flat mirror whose height can be changed by λ / 4 by rotating clockwise or counterclockwise. Can be reflected by changing by 0 or π. Therefore, in the following, the mirror element 30 in the first state in FIG. 4A is also referred to as a mirror element 30 (0) in which the phase of the reflected light is 0, and the mirror element in the second state in FIG. 30 is also referred to as a mirror element 30 (π) that makes the phase of the reflected light π. By individually setting a large number of mirror elements 30 of the spatial light modulator 28 to the mirror elements 30 (0) or 30 (π), the phase distribution of the reflected light can be set to an arbitrary distribution in the same manner as the phase shift mask. is there.

  For example, as shown in FIG. 5A, when the ordinary flat mirror element 80 is rotated clockwise, the complex amplitude of the reflected light at the left and right reflecting portions 81A and 81B of the mirror element 80 is They are distributed symmetrically with respect to the real axis Re in the fourth quadrant area BB3 and the first quadrant area BA3 of FIG. Therefore, the average complex amplitude of the reflected light from the entire mirror element 80 in FIG. 5A becomes a positive value A3a on the real axis Re. On the other hand, as shown in FIG. 5C, when the mirror element 80 is rotated counterclockwise, the complex amplitudes of the reflected light at the reflecting portions 81A and 81B are in the first quadrant of FIG. 5D, respectively. The region BA4 and the fourth quadrant region BB4 are distributed symmetrically with respect to the real axis Re. Therefore, the average complex amplitude of the reflected light from the entire mirror element 80 in FIG. 5C also cancels out the imaginary part on the left and right, so that the positive value A4a on the real axis Re in FIG. Become. Therefore, the phase of the reflected light remains the same regardless of whether the normal flat mirror element 80 rotates clockwise or counterclockwise.

  Further, as shown in FIG. 3A, the first reflecting portion 31A constituting the mirror element 30 of the present embodiment has a portion 31Aa having a distance a1 on the XY plane from the rotation axis RC and a width b1 in the V direction. And a portion 31Ab having a width a2 larger than a1 and a width b2 wider than the width b1. Further, the areas of the reflecting portions 31A and 31B constituting the mirror element 30 become wider as the distance from the rotational axis RC increases. The average complex amplitude of the reflected light when the mirror element 30 having such a shape is rotated to the first state 30 (0) in FIG. 4A will be considered with reference to FIG. First, the reflected light from the surface away from the rotation axis RC is in the region BC1 near the positive limit on the real axis Re in FIG. 4B, and the reflected light from the surface near the rotation axis RC is the real part. Is in the region BC2 close to zero. A large area away from the rotation axis RC and a small area near the rotation axis RC mean that the reflected beam has a large amount of light in the region BC1 and a small amount of light in the region BC2. That is, the average complex amplitude of the reflected light of the mirror element 30 is larger in the positive direction than the case where the reflection area does not depend on the distance from the rotation axis RC and the mirror shape is constant. Similarly, when the mirror element 30 having such a shape is rotated to the second state 30 (π) in FIG. 4C, a negative value on the real axis Re in FIG. The number of light rays in the region near the limit increases, and the average complex amplitude of the reflected light increases in the negative direction. Therefore, when the phase distribution of the reflected light is controlled using the mirror element 30 having a shape that increases in area as the distance from the rotation axis RC increases, the shape has a substantially constant area regardless of the distance from the rotation axis RC The intensity of the reflected light can be increased as compared with the case of using a mirror element having a substantially square step having a side parallel to the rotation axis RC.

  Returning to FIG. 1, as an example, the phase distribution (uneven pattern) of the illumination light IL set by the spatial light modulator 28 in the modulation control unit 48 by the main control system 40 every time the illumination light IL having a predetermined number of pulses is emitted. Supply information. In response to this, the modulation controller 48 controls each mirror element 30 of the spatial light modulator 28 to the first state (phase 0) or the second state (phase π). An aerial image corresponding to the phase distribution is formed on the surface of the wafer W.

  The illumination light IL reflected by the array of a large number of mirror elements 30 in the illumination area 26A of the spatial light modulator 28 enters the projection optical system PL via the half mirror 24. Projection optical system PL having optical axis AX supported by a column (not shown) is a double-sided telecentric reduction projection optical system. The projection optical system PL converts a reduced image of the aerial image corresponding to the phase distribution of the illumination light IL set by the spatial light modulator 28 into an exposure area 26B (an illumination area 26A and an illumination area 26A) in one shot area of the wafer W. To a region conjugate to The projection magnification β of the projection optical system PL is, for example, about 1/10 to 1/100, and the resolution (half pitch or line width) is, for example, about the width of the image of the mirror element 30 of the spatial light modulator 28. In other words, a structure smaller than the width of one mirror element 30 is not resolved on the object plane of the projection optical system PL. For example, when the width of the mirror element 30 is about several μm and the projection magnification β of the projection optical system PL is about 1/100, the resolution of the projection optical system PL is about several tens of nm.

  The wafer W (substrate) includes, for example, a surface of a circular flat base material such as silicon or SOI (silicon on insulator) applied with a photoresist (photosensitive material) with a thickness of about several tens to 200 nm. . Further, when the exposure apparatus EX is of an immersion type, for example, as disclosed in US Patent Application Publication No. 2007/242247, a space between the optical member at the tip of the projection optical system PL and the wafer W is disclosed. A local liquid immersion device for supplying and recovering a liquid (for example, pure water) that transmits the illumination light IL is provided. In the case of the immersion type, the resolution can be further increased.

  In FIG. 1, a wafer W is sucked and held on the upper surface of a wafer stage WST via a wafer holder (not shown), and the wafer stage WST performs step movement in the X direction and the Y direction on a guide surface (not shown). Move at a constant speed in the direction. The position of wafer stage WST in the X and Y directions, the rotation angle in the θz direction, and the like are formed by laser interferometer 45, and this measurement information is supplied to stage control system 44. Stage control system 44 controls the position and speed of wafer stage WST via drive system 46 such as a linear motor based on control information from main control system 40 and measurement information from laser interferometer 45. In order to perform alignment of the wafer W, an alignment system (not shown) for detecting the position of the alignment mark on the wafer W is also provided.

  When the wafer W is exposed, the illumination condition of the illumination optical system ILS is set after the alignment of the wafer W is performed. Then, for example, the wafer W is positioned at the scanning start position in order to perform exposure on the shot areas SA21, SA22,... Arranged in a line in the Y direction on the surface of the wafer W shown in FIG. Thereafter, scanning of the wafer W at a constant speed in the + Y direction is started. 6A indicates the relative movement direction of the exposure area 26B with respect to the wafer W.

  Next, the main control system 40 reflects the reflection of the spatial light modulator 28 corresponding to the aerial image formed in the exposure area 26B in the modulation control unit 48 according to the relative position of the exposure area 26B of the wafer W to the shot area SA21. Information on the phase distribution of the illumination light IL on the surface is supplied, and a light emission trigger pulse TP is supplied to the power supply unit 42. As a result, a target aerial image is sequentially exposed in the exposure area 26B according to the position in the Y direction. By repeating this operation until the shot area SA21 crosses the exposure area 26B, the entire aerial image (circuit pattern) is exposed in the shot area SA21.

  Thereafter, in order to expose the shot area SA22 adjacent to the shot area SA21 of the wafer W, the main control system 40 sends the phase distribution information of the illumination light IL to the modulation controller 48 while scanning the wafer W in the same direction. While supplying, the light emission trigger pulse TP is supplied to the power supply part 42. In this way, continuous exposure can be performed from the shot areas SA21 to SA22. 6A, when shifting to exposure of a row including shot areas SA31 and SA32 adjacent in the X direction of the wafer W, the wafer stage WST is driven to move the wafer W in the X direction (perpendicular to the scanning direction). In the non-scanning direction). Then, the scanning direction of the wafer W with respect to the exposure region 26B indicated by the dotted line is set to the opposite −Y direction, and information on the phase distribution of the illumination light IL is supplied from the main control system 40 to the modulation control unit 48 in the reverse order. By supplying the light emission trigger pulse TP to the power supply unit 42, the exposure can be continuously performed from the shot areas SA32 to SA31. In this exposure, it is possible to expose different aerial images to the shot areas SA21, SA22 and the like. Each shot area may be exposed by a plurality of scans. Thereafter, the photoresist on the wafer W is developed, so that a resist pattern is formed in each shot area of the wafer W.

  Next, the intensity and reflectance of the reflected light from the mirror element 30 of the spatial light modulator 28 of this embodiment will be quantitatively described. Here, as a comparative example, as shown in FIG. 7, a square stepped mirror element 73 having sides parallel to the X axis and the Y axis is assumed. The mirror element 73 is supported so as to be rotatable about a rotation axis RC parallel to the X axis, and is symmetric with respect to the rotation axis RC. The first reflection portion 74A in the + Y direction and the second reflection portion 74B in the −Y direction. And a step part 74C having a step d1 (= λ / 4) is provided between the reflection parts 74A and 74B. Accordingly, the step 74B is parallel to the polarization direction PX. The width of the mirror element 73 in the X direction (Y direction) is equal to the width of the mirror element 30 in FIG. 3A in the V direction (U direction).

  Here, as shown in FIG. 4C, the rotation angle α of the mirror element 30 and the mirror element 73 of the comparative example is the amount of change φ of the phase of the reflected light at the edge part of the tip of the first reflecting part 31A (74A). Curves C10 and C40 in FIG. 8A are obtained by converting the electric field amplitude EA of the reflected light from the mirror elements 30 and 73 as a function of the rotation angle φ (deg) as a scalar value. The curves C20 and C30 will be described later (the same applies hereinafter).

  Further, the scalar calculation formulas of the electric field amplitude of the reflected light from the mirror element 73 of the comparative example (normal) and the mirror element 30 having the triangular first reflecting portion 31A of the present embodiment are the following formula (2A) and (2B). These formulas are area average values of the electric field amplitude of the reflection portion, and were obtained by the same method as described in Non-Patent Document 1.

また、図８（Ａ）の曲線Ｃ４０及びＣ１０に対応する反射光の強度Ｉは、回転角φの関数として図８（Ｂ）の曲線Ｃ４及びＣ１となる。曲線Ｃ１の最大値０．７６は曲線Ｃ４の最大値０．５３のほぼ１．４３倍であるため、本実施形態のミラー要素３０を用いることによって、比較例のミラー要素７３を用いる場合に比べて反射光の強度がほぼ１．４３倍になることが分かる。

Also, the intensity I of the reflected light corresponding to the curves C40 and C10 in FIG. 8A becomes the curves C4 and C1 in FIG. 8B as a function of the rotation angle φ. Since the maximum value 0.76 of the curve C1 is approximately 1.43 times the maximum value 0.53 of the curve C4, the use of the mirror element 30 of the present embodiment is compared to the case of using the mirror element 73 of the comparative example. It can be seen that the intensity of the reflected light is about 1.43 times.

Further, the rotation angle ± α in the first and second states of the mirror element 30 in FIG. 3B is the rotation angle φ converted to the phase of the reflected light, and the intensity I of the reflected light in FIG. The maximum value (approximately −120 ° and + 120 °) may be set. This maximizes the intensity of the reflected light.
Regarding the mirror element 30 of the present embodiment and the mirror element 73 of the comparative example, the incident light is randomly polarized light, linearly polarized light in the X direction (X polarized light), and linearly polarized light in the Y direction (Y polarized light). The results of calculating the relationship between the mirror element rotation angle φ (deg) and the reflectance are curves CD1 and CD5 in FIGS. 9A, 9B, and 9C, respectively. Here, the dimensions of the mirror element 30 in FIG. 9 are as follows. The width in the U direction shown in FIG. 3A is 1414 nm, the width in the V direction is (1414-140) nm, The width in the V direction was 140 nm. Further, the dimension of the mirror element 73 in FIG. 9 is 1000 nm in both the X direction and the Y direction shown in FIG. That is, both the mirror element 30 and the mirror element 73 have a pitch of 1000 nm in the X direction and the Y direction. For these calculations, electromagnetic field analysis software by the FDTD method (finite difference time domain method) is used. Further, curves CD1 and CD5 in FIG. 9D show the relationship between the rotation angle φ calculated based on the scalar calculation formula and the reflectance with respect to the mirror elements 30 and 73. In these calculations, it is assumed that the projection optical system PL is non-telecentric on the object side, and the incident angle of the illumination light IL with respect to the mirror elements 30 and 73 is 6 ° in the θx direction. 9A to 9D, when the rotation angle φ is in the negative range, the mirror elements 30 and 73 are in the first state (the phase of the reflected light is 0), and when the rotation angle φ is in the positive range, the mirror element. 30 and 73 are in the second state (the phase of the reflected light is π). In FIGS. 9A to 9D, the mirror of the present embodiment is compared with the reflectance (curve CD5) of the comparative example (normal) when the rotation angle φ is in the range of approximately −150 ° to + 150 °. Since the reflectance (curve CD1) of the element 30 is large, it can be seen that by using the mirror element 30 of this embodiment, the reflectance is improved regardless of the polarization state of the incident light. In all the curves in FIG. 9, the phase of the reflected light is 0 and π, respectively, and the intensity has a maximum value, and the maximum value is the maximum reflectance that can be obtained by the mirror element. Comparing the maximum reflectance with the curve CD5 in FIGS. 9B and 9C, when the phase of the reflected light is 0, the X-polarized light in FIG. 9B is 0.46, whereas The Y-polarized light in FIG. 9C is 0.60, which is different by about 1.3 times. Similarly, when the phase of the reflected light is π, the X-polarized light in FIG. 9B is 0.36, whereas the Y-polarized light in FIG. 9C is 0.48. Three times different. Thus, it can be seen that the mirror element 73 has different reflectivities depending on the polarization state. However, focusing on the curve CD1 in FIGS. 9B and 9C, when the phase of the reflected light is 0, the X-polarized light in FIG. 9B is 0.69, whereas FIG. ) Of Y-polarized light is approximately equal to 0.70, and when the phase of the reflected light is π, both X-polarized light in FIG. 9B and Y-polarized light in FIG. 9C are 0.53. Thus, in the mirror element 30, the mirror rotation axis RC is directed in the V direction intersecting at 45 ° with respect to the X axis and the Y axis, so that a difference due to the polarization direction is less likely to occur.

  Next, an example of a simulation result when an isolated pattern (resist pattern) is formed on the surface of the wafer in the present embodiment will be described. Here, as an example, a resist pattern to be formed on the surface of the wafer W after development, as shown in FIGS. 10B and 10D, is approximately 40 nm in the X direction and 48 nm in the Y direction, and the X direction. Are a pair of symmetrical, substantially square targets 76A and 76B arranged at an interval of 40 nm. In FIG. 10B and the like, the horizontal axis and the vertical axis are the X axis (nm) and the Y axis (nm) on the image plane of the projection optical system PL, respectively.

  10A and 10C are formed by an array of mirror elements 30 of this embodiment and an array of mirror elements 73 of a comparative example of FIG. 7 respectively, in order to form a resist pattern as close as possible to the targets 76A and 76B. It is a perspective view which shows an example of phase distribution 50A and 50B (distribution of the mirror element of a 1st and 2nd state) of illumination light IL to be performed. For convenience of explanation, it is assumed that the projection optical system PL forms an erect image. Further, of the mirror elements 30 and 73, the mirror element in the first state (phase 0 of reflected light) is represented by a white pattern, and the mirror element in the second state (phase π of reflected light) is represented by a gray pattern. Represented by

  10A and 10C, patterns 75A and 75B optically conjugate with the targets 76A and 76B are virtually represented by dotted lines. Further, the pitch in the X direction and Y direction of the arrangement of the individual mirror elements 30 and 73 is set to 20 nm at the stage of the projected image. The peripheral portion of the phase distribution 50A (50B) is obtained by arranging the mirror elements 30 (73) in the first state and the mirror elements 30 (73) in the second state in a checkerboard pattern.

  Using the phase distributions 50A and 50B, the light quantity distribution of the illumination light IL on the illumination pupil plane IPP is optimized so as to obtain a high resolution, and the illumination light IL linearly polarized in the Y direction is used. The intensity distribution of the aerial image on the image plane at the best focus position of the projection optical system PL and the position defocused by ± 40 nm was obtained by simulation. Further, a theoretical resist pattern obtained by slicing those aerial images with a predetermined threshold value (for example, a value at which the maximum value of the width in the X direction becomes the target value) is an elliptical pattern 77A in FIG. 77B and the elliptical pattern of FIG. From a comparison between FIG. 10 (B) and FIG. 10 (D), even when the array of mirror elements 30 of the present embodiment is used, a resist pattern almost the same as that when the array of mirror elements 73 of the comparative example is used is obtained. Thus, it can be seen that the mirror element 30 can be used to form an actual pattern.

  Further, FIG. 11A shows a resist pattern corresponding to FIG. 10B and FIG. 10D, and FIG. 11B is a straight line with a Y coordinate of −20 nm in FIG. The distribution of the intensity I of the image plane at position X) is shown. Curves CA1, CA4, and CA5 in FIG. 11B are intensities when an array of mirror elements 30 of this embodiment, an array of mirror elements 73 of a comparative example, and an array of plane mirrors with variable heights are used. Show the distribution. These intensity distributions are normalized so that the maximum value of the intensity distribution is 1 when an array of plane mirrors with variable height is used. Here, the reflectance of the single mirror element is 0.76 for the mirror element 30, 0.53 for the mirror element 73, and 1.0 for a flat mirror with a variable height, and uses a scalar calculation value. As can be seen from FIG. 11B, the maximum intensity 0.71 of the curve CA1 is higher than the maximum intensity 0.53 of the curve CA4. Compared to the reflectance 0.76 of the mirror element 30 alone, the maximum intensity in the curve CA1 is slightly reduced to 0.71, but the mirror element 30 is still a high value compared to the maximum intensity in the curve CA4. It can be seen that higher strength can be obtained when using the mirror element 73 than when using the mirror element 73. The reason why the maximum intensity of the pattern is slightly lower than the reflectance of the single mirror is that the intensity of the phase distribution 50A is lower than that of 50B. That is, in the phase distribution 50A, there is a light amount loss because the edge portions of the first state and the second state are in small increments.

  Next, when the incident light is X-polarized light or Y-polarized light, the intensity I of the reflected light from the mirror element 30 of the present embodiment corresponds to the curves CB1 and CB2 in FIG. As shown, it becomes slightly asymmetric. Here, the mirror dimensions used in FIG. 12 are different from the dimensions used in the calculation of FIG. That is, the maximum intensity I in the first state (φ is negative and the phase of the reflected light is 0) is larger than the maximum intensity I in the second state (φ is positive and the phase of the reflected light is π). Slightly larger. In order to correct this asymmetry, a connecting portion 72 having a different height is provided between the reflecting portions 31A and 31B as shown by a mirror element 71 of a second modified example in FIG. The height of the portion 72 may be set so that the amount of change in the phase of the reflected light is π. Note that the amount of change in the phase of the reflected light at the first reflecting portion 31A is π / 2.

  In this way, when the amount of change in the phase of the reflected light of the connecting portion 72 is set to π, when the incident light is X-polarized light or Y-polarized light, the intensity I of the reflected light from the mirror element 71 is the curve of FIG. As shown by CB3 and CB4. That is, in the phase π region, the curves CB3 and CB4 show higher intensities than the curves CB1 and CB2, respectively. Conversely, in the phase 0 region, the curves CB3 and CB4 show lower intensities than the curves CB1 and CB2, respectively. . Therefore, by further optimizing the area of the connecting portion 72, the intensity of the reflected light of phase 0 and π can be made comparable.

  Next, when the stepped mirror elements 30 and 73 of the present embodiment and the comparative example are used, if the incident light is polarized, as can be seen from the curves CD2 and CD5 in FIGS. The maximum reflectance in the first state (φ is negative and the phase of the reflected light is 0) is larger than the maximum reflectance in the second state (φ is positive and the phase of the reflected light is π). ing. In this case, for example, if the phase distribution of the array of mirror elements 30 is set to the phase distribution 50A of FIG. 13A using Y-polarized illumination light (the reflectivity of phase 0 is 0.60, the reflectivity of phase π is 0.48), the resist pattern obtained at the best focus position and the position defocused by ± 40 nm has a smaller right pattern as shown in FIG.

  In this case, if the phase distribution of the array of mirror elements 30 is set to the phase distribution 51A in FIG. 13C obtained by inverting the phase distribution 50A, the resist pattern obtained at the best focus position and the position defocused by ± 40 nm is as shown in FIG. As shown in FIG. 13D, the right pattern becomes larger as opposed to FIG. Therefore, when the reflectivity in the first state of the mirror element 30 is different from the maximum reflectivity in the second state, the exposure with the phase distribution 50A in FIG. Double exposure with exposure using the inverted phase distribution 51A) may be performed. As shown in FIG. 13E, the resist pattern obtained by this double exposure has the same left and right pattern sizes, and the intensity distribution is also symmetrical. As described above, it is possible to make the strengths of the two phases uniform by optimizing the area of the connection portion between the phases 0 and π. However, even if the strengths of the two phases are not matched, 0 and π are inverted. By performing double exposure with the phase distribution thus obtained, problems with different reflectivities can be solved.

The effects and the like of this embodiment are as follows.
(1) The exposure apparatus EX of the present embodiment includes a spatial light modulator 28. The spatial light modulator 28 includes an array of a plurality of mirror elements 30 that are each irradiated with the illumination light IL, and the mirror elements 30 are supported so as to be rotatable around the rotation axis RC. Further, the mirror element 30 is located at a distance a1 from the rotation axis RC and has a portion 31Aa having a width b1 in a direction parallel to the rotation axis RC, and at a distance a2 away from the rotation axis RC from the distance a1 and parallel to the rotation axis RC. A first reflecting portion 31A including a portion 31Ab having a width b2 wider than the width b1 in a certain direction. The first reflecting portion 31A has a triangular shape arranged with one apex facing the rotation axis RC side.

  According to the present embodiment, since the first reflecting portion 31A of the mirror element 30 includes a portion whose width (area) increases as the distance from the rotation axis RC increases, the rotation angle φ (rotation angle α) of the mirror element 30 is included. ) To control the phase of the reflected light, the intensity (reflectance) of the reflected light increases. Also, the intensity of the aerial image formed by the reflected light from the array of mirror elements 30 is increased.

  (2) Further, the mirror element 30 has a second reflecting portion 31B that is symmetrical to the first reflecting portion 31A with respect to the rotation axis RC, and the amount of change in the phase of the reflected light is 180 between the reflecting portions 31A and 31B. There is a step portion 31C having a step d1 that is ° (π). Accordingly, since the amount of change in the phase of the reflected light from the mirror element 30 differs by 180 ° with the mirror element 30 rotated clockwise and counterclockwise around the rotation axis RC, an array of mirror elements 30 is used. An arbitrary phase distribution of reflected light can be generated with the mirror element 30 as a unit.

  For example, when the power of the spatial light modulator 28 is turned off and the reflecting surface of the mirror element 30 is parallel to the base member 32, the mirror element 30 changes the power off state to the first state (reflected light). It is also possible to use the state in which the phase is 0) and the mirror element 30 is rotated by a predetermined angle clockwise or counterclockwise around the rotation axis RC as the second state (the phase of the reflected light is π).

  (3) Further, the crossing angle between the step portion 31C of the mirror element 30 and the X axis and the Y axis is 45 °. Accordingly, when the polarization direction of the illumination light IL is set to the X direction or the Y direction as in the case of forming a normal pattern on the wafer W, the difference in reflectance is eliminated, so that various patterns are formed on the wafer W. Can be faithfully formed. The crossing angle may be an angle greater than 0 ° and smaller than 90 °, which reduces the difference in reflectance depending on the polarization direction.

However, in the present embodiment, the mirror element 30 may be arranged such that the stepped portion 31C is parallel to the X direction or the Y direction. Even in this arrangement, the area of the mirror element 30 increases as the distance from the rotation axis RC increases, so that the intensity (reflectance) of reflected light increases.
(4) Since the mirror element 30 of the spatial light modulator 28 is a two-dimensional array, a large-area pattern can be exposed on the wafer W by a single exposure. In the spatial light modulator 28, the mirror elements 30 may be arranged in a one-dimensional array, for example, in the X direction (direction corresponding to the non-scanning direction of the wafer W).

  (5) The exposure apparatus EX is an exposure apparatus that exposes the wafer W (substrate) with illumination light IL (exposure light). The spatial light modulator 28 and an array of a plurality of mirror elements 30 of the spatial light modulator 28 are used. An illumination optical system ILS that irradiates the illumination light IL to the wafer W, a projection optical system PL that projects the pattern onto the wafer W by guiding the reflected light from the plurality of mirror elements 30 onto the wafer W, and a pattern exposed to the wafer W. In order to control the plurality of mirror elements 30 of the spatial light modulator 28, the modulation control unit 48 (control device) for individually controlling the mirror element 30 to the first state or the second state.

According to the exposure apparatus EX, since the intensity of the reflected light of the illumination light IL at the mirror element 30 is large, the utilization efficiency of the illumination light IL is increased, and the intensity of the aerial image is increased, so that the throughput of the wafer W is high. The target pattern can be formed with high accuracy.
Each mirror element 30 of the spatial light modulator 28 may be set to a plurality of states including a first state and a third state other than the second state.

  (6) Further, the mirror element 30 is provided in a rectangular region whose longitudinal direction is the X direction, and moves the wafer W in a scanning direction corresponding to the Y direction orthogonal to the X direction on the image plane of the projection optical system PL. A wafer stage WST (substrate stage) is provided, and the modulation control unit 48 moves a pattern (phase distribution) formed by the plurality of mirror elements 30 in the Y direction in accordance with the movement of the wafer W by the wafer stage WST. Thereby, the entire surface of the wafer W can be efficiently exposed.

In the above embodiment, the following modifications are possible.
First, the mirror element 30 of the above embodiment is symmetric with respect to the rotation axis RC. On the other hand, as shown by the mirror unit 70 of the first modified example in FIG. 14A, the first and second support drive units 34A and 34B having the same configuration as the support drive unit 34 in FIG. The first reflecting portion 31A and the second reflecting portion 31B that are symmetrical with each other may be supported. In this modification, electrodes 37A and 37B are provided on the bottom surfaces of the reflecting portions 31A and 31B, respectively, and electrodes 37C and 37D are provided on the base member 32 so as to face the electrodes 37A and 37B. As an example, when the reflecting portions 31A and 31B are parallel to the base member 32, the illumination light IL is inclined on the average and enters the reflecting portions 31A and 31B (this state is the first state). When the first reflecting portion 31A is rotated clockwise by the support driving portion 34A, the phase of the reflected light is π by rotating the second reflecting portion 31B counterclockwise by the supporting drive portion 34B. A second state can be set. The mirror units 70 are also arranged at a predetermined pitch in the X and Y directions with almost no gap. Since this mirror unit 70 also includes a reflecting portion whose area increases as the distance from the rotation axis RC increases, the intensity of the reflected light increases.

When the mirror unit 70 is used, the direction of the rotation axis RC may be a direction that intersects the X direction and the Y direction at 45 °, but the direction of the rotation axis RC may be set parallel to the X direction or the Y direction. .
Next, as shown by the mirror element 71 of the second modified example in FIG. 14B, a connecting portion 72 having a height different from that of the reflecting portions 31A and 31B may be provided between the reflecting portions 31A and 31B. In the example of FIG. 14B, the surface of the connecting portion 72 is set higher than the surface of the second reflecting portion 31B by a level difference d2, and higher than the surface of the first reflecting portion 31A. Even in this case, the step between the reflecting portions 31A and 31B is set to be equal to the step d1 (the phase difference of the reflected light is π) in FIG. The level difference d2 is, for example, 3π / 2 in terms of a phase difference. Other configurations are the same as those in FIG. 3A, and the intensity of the reflected light increases even when this mirror element 71 is used. At this time, the area of the connecting portion 72 may be adjusted in order to correct the difference in reflectance when the mirror element 71 is set to the first state and the second state.

  In addition, you may set the height of the surface of the connection part 72 to the center height of the surface of 31 A of 1st surface parts, and the surface of the 2nd surface part 31B. Thus, when the height of the connecting portion 72 is the center of the height of the reflecting portions 31A and 31B, the amount of change in the phase of the reflected light at the reflecting portions 31A and 31B is ± π / 2. The amount of change in the phase of the reflected light at 0 is zero. Further, by adjusting the area of the connecting portion 72, it may be possible to correct the difference in reflectance when the mirror element 71 is set to the first state and the second state.

Moreover, you may make the reflectance of the connection part 72 lower than the reflectance of reflection part 31A, 31B.
Next, FIG. 15A is an enlarged bottom view showing a part of the reflecting surface of the spatial light modulator 28A of the third modification, and FIG. 15B is one mirror element 30A in FIG. 15A. FIG. 16A shows three mirror elements 30A in FIG. 15A, and FIG. 16B shows one of the mirror elements 30A viewed along the BB line parallel to the U direction in FIG. A mirror element 30A is shown. 15A to 16B, portions corresponding to those in FIGS. 2A to 3C are denoted by the same reference numerals, and detailed description thereof is omitted.

  In FIG. 15B, the mirror element 30A is rotatable around a rotation axis RC parallel to the V direction that intersects the X axis and the Y axis at 45 °. Further, the mirror element 30A includes a T-shaped first portion 31Da in which a linear flat first portion 31Da parallel to the rotation axis RC and a linear flat second portion 31Db perpendicular to the rotation axis RC are connected. A first reflecting portion 31D and a T-shaped plate-like second reflecting portion 31E symmetrical to the first reflecting portion 31D with respect to the rotation axis RC, and between the first reflecting portion 31D and the second reflecting portion 31E. Is formed with a step portion 31F in a plane including the rotation axis RC.

  The step difference of the step portion 31F parallel to the V direction is d1 (π in the phase difference of the reflected light) which is the same as the step portion 31C of FIG. 2B (see FIG. 16B). Further, the length of the first portion 31Da in the V direction is d, and the width of the second portion 31Db in the V direction is R · d using a predetermined pattern R (0 <R <1). The width in the U direction of the first portion 31Da is substantially the same as the length in the U direction of the second portion 31Db. Further, the width in the V direction and the length in the U direction of the mirror element 30A are substantially the same. The width in the V direction and the length in the U direction of the mirror element 30A are, for example, about 1 to 10 μm.

As shown in FIG. 15A, the multiple mirror elements 30A are arranged close to each other in the X direction and the Y direction so that there is almost no gap as a whole. Therefore, even if the reflecting portions 31D and 31E of the individual mirror elements 30A are T-shaped, the utilization efficiency of the illumination light IL is high.
In FIG. 16A, each mirror element 30A is supported on the surface of the base member 32 by the support driving unit 34. Electrodes 37A and 37B are formed on the bottom surfaces of the reflecting portions 31D and 31E of the mirror element 30A, respectively, and electrodes 37C and 37D are formed on the surface of the base member 32 so as to face the electrodes 37A and 37B, respectively. The mirror element 30A of this modification also has a first state (30A (0)) indicated by a dotted line rotated clockwise by a predetermined angle around the rotation axis RC in FIG. 16B, or around the rotation axis RC. Is set to one of the second states (30A (π)) indicated by a solid line rotated counterclockwise by a predetermined angle. The stepped mirror element 30A is also reflected by changing the phase of incident light by 0 or π by rotating clockwise or counterclockwise and setting to the first state or the second state. can do.

  Further, as shown in FIG. 16A, the first reflecting portion 31D constituting the mirror element 30A of the present modification has an average distance a3 on the XY plane from the rotation axis RC and a width R · d in the V direction. Second portion 31Db, and an average distance a4 from the rotation axis RC is larger than a3, and a first portion 31Da having a width d wider than the width R · d. Accordingly, the areas of the reflecting portions 31D and 31E constituting the mirror element 30A become wider as the distance from the rotational axis RC increases. When the mirror element 30A having such a shape is used, as in the case of using the mirror element 30 in FIG. 3A, for example, a substantially square stepped mirror element having sides parallel to the rotation axis RC is used. Compared to the above, it is possible to increase the intensity of the reflected light.

Further, since the step portion 31F is parallel to the direction V, the mirror element 30A can reduce the difference in reflectance when the X-polarized or Y-polarized illumination light IL is used.
Next, the intensity and reflectance of the reflected light from the mirror element 30A of the spatial light modulator 28A of this modification will be quantitatively described. The scalar calculation formula of the electric field amplitude of the reflected light from the mirror element 30A can be expressed by the following formula (2C).

図１７（Ａ）は、ミラー要素３０Ａの第２部分３１Ｄｂの幅Ｒ・ｄを規定するパラメータＲの値を０．１〜０．５まで変化させて、ミラー要素３０Ａの回転角φ（反射部３１Ｄ，３１Ｅのエッジ部での反射光の位相の変化量に換算した値）とミラー要素３０からの反射光の強度Ｉとの関係をシミュレーションで求めた結果を示す。また、図１７（Ｂ）は、図１７（Ａ）のパラメータＲの値と反射光の強度Ｉの最大値Ｉｍａｘとの関係を示す。図１７（Ｂ）からパラメータＲの値が小さいほど、すなわち、ミラー要素３０Ａの回転軸ＲＣから離れた部分の面積の割合が大きいほど、反射光の強度が大きくなることが分かる。

In FIG. 17A, the value of the parameter R that defines the width R · d of the second portion 31Db of the mirror element 30A is changed from 0.1 to 0.5, and the rotation angle φ (reflection part) of the mirror element 30A is changed. The result of having calculated | required the relationship between the intensity | strength I of the reflected light from the mirror element 30 and the value converted into the variation | change_quantity of the phase of the reflected light in the edge parts of 31D and 31E by simulation is shown. FIG. 17B shows the relationship between the value of parameter R in FIG. 17A and the maximum value Imax of the intensity I of reflected light. It can be seen from FIG. 17B that the intensity of the reflected light increases as the value of the parameter R decreases, that is, as the ratio of the area of the part away from the rotation axis RC of the mirror element 30A increases.

A curve C20 in FIG. 8A represents the electric field amplitude EA when the parameter R is 0.1.
Further, the intensity I of the reflected light corresponding to the curve C20 in FIG. 8A becomes the curve C2 in FIG. 8B as a function of the rotation angle φ. Since the maximum value 0.82 of the curve C2 is larger than the maximum value 0.76 of the curve C1, the intensity of the reflected light is further increased by using the mirror element 30A compared to the case of using the mirror element 30 of the above embodiment. You can see that it can be enlarged.

  Further, as an example, the U-shaped width of the T-shaped mirror element 30A with a step is 1414 nm, the width in the V direction is (1414-140) nm, and the width in the V direction of the second portion 31Db of the mirror element 30A is 140 nm. (Ie, parameter R = 0.1), when the incident light is random polarized light, X polarized light, and Y polarized light, the mirror element rotation angle φ (deg) and the reflectance The results of calculating the relationship are curves CD2 in FIGS. 9A, 9B, and 9C, respectively. Further, a curve CD2 in FIG. 9D shows the relationship between the rotation angle φ calculated based on the scalar calculation formula and the reflectance with respect to the mirror element 30A. 9A to 9D, the reflectivity of the mirror element 30A of the present modification (curve CD1) with respect to the reflectivity (curve CD1) of the above-described embodiment over almost the entire range of the rotation angle φ. Since the curve CD2) is large, it can be seen that by using the mirror element 30A, the reflectance is further improved regardless of the polarization state of the incident light. Also, like the mirror element 30, the difference between the X-polarized light and the Y-polarized light is less likely to occur because the rotation axis RC of the mirror is oriented in the V direction that intersects the X axis and the Y axis at 45 °. Recognize.

  Next, an example of a simulation result when an isolated pattern (resist pattern) is formed on the surface of the wafer in the present embodiment will be described. Here, it is assumed that the resist pattern to be formed on the surface of the wafer W after development is a pair of left and right symmetrical substantially square targets 76A and 76B as shown in FIG. 18B as an example. FIG. 18A shows the phase distribution 50C of illumination light IL (first and second state mirror elements) formed by an array of mirror elements 30A to form a resist pattern as close as possible to the targets 76A and 76B. It is a perspective view which shows an example of (distribution of).

  Using the phase distribution 50C under the same conditions as in the above embodiment, the intensity distribution of the aerial image on the image plane at the best focus position of the projection optical system PL and the position defocused by ± 40 nm was obtained by simulation. Further, theoretical resist patterns obtained by slicing the aerial image with a predetermined threshold are elliptical patterns 77C and 77D in FIG. From the comparison between FIG. 18 (B) and FIG. 10 (D), even when the array of mirror elements 30A is used, a resist pattern almost the same as that obtained when the array of mirror elements 73 of the comparative example is used is obtained. It can be seen that 30A can be used to form an actual pattern. In addition, the intensity distribution on a straight line with a Y coordinate of −20 nm in FIG. 18B is a curve CA2 in FIG. The maximum intensity 0.75 of the curve CA2 is higher than the maximum intensity 0.53 of the curve CA4, and further higher than the maximum intensity 0.71 of the curve CA1. From this, it can be seen that when the parameter R is 0.1 in the mirror element 30A, the reflection intensity further increases.

In this modification as well, the exposure of the phase distribution 50C and the phase distribution 50C are reversed in order to correct the influence of the difference in reflectance when the mirror element 30A is set to the first state or the second state. You may make it perform exposure of phase distribution twice.
Further, a connecting portion having a height different from that of the reflecting portions 31D and 31E may be provided in a region centering on the step portion 31F of the mirror element 30A.
Further, the reflectance of the second portion 31Db of the mirror element 30A may be smaller than the reflectance of the first portion 31Da.
Furthermore, the step portion 31F of the mirror element 30A can be arranged in parallel to the X axis or the Y axis.

[Second Embodiment]
Next, a second embodiment will be described with reference to FIGS. 19 (A) to 20 (B). FIG. 19A is an enlarged bottom view showing a part of the reflection surface of the spatial light modulator 28B of the second embodiment, and FIG. 19B shows one mirror element 30B in FIG. 19A. It is an enlarged view. 20A shows one mirror element 30B in FIG. 19A, and FIG. 20B shows the mirror element 30B in FIG. 20A along the BB line parallel to the U direction. FIG. 19A to 20B, portions corresponding to those in FIGS. 2A to 3C are denoted by the same reference numerals, and detailed description thereof is omitted.

  In FIG. 19B, the mirror element 30B is rotatable around a rotation axis RC parallel to the V direction intersecting at 45 ° with respect to the X axis and the Y axis. Further, the mirror element 30B is a square surrounded by sides parallel to the X direction and the Y direction as a whole, and a symmetrical triangular first reflecting portion 31G and a second reflecting portion 31I parallel to the rotation axis RC. It is divided into the reflection part 31H.

The step difference of the step portion 31I parallel to the V direction is d1 (π in the phase difference of the reflected light) which is the same as the step portion 31C of FIG. 2B (see FIG. 20A). Further, the width in the X direction and the width in the Y direction of the mirror element 30B are substantially the same. The width in the X direction and the Y direction of the mirror element 30B is, for example, about 1 to 10 μm.
As shown in FIG. 19A, a large number of mirror elements 30B are arranged close to each other in the X direction and the Y direction so that there is almost no gap as a whole. Therefore, the utilization efficiency of the illumination light IL is high.

  In FIG. 20A, the mirror element 30 </ b> B is supported on the surface of the base member 32 by the support driving unit 34. Electrodes 37A and 37B are formed on the bottom surfaces of the reflecting portions 31G and 31H of the mirror element 30B (see FIG. 21B), and electrodes 37C and 37D are respectively formed on the surface of the base member 32 so as to face the electrodes 37A and 37B. Is formed. In FIG. 20B, the mirror element 30B of this embodiment also has a first state (30B (0)) indicated by a dotted line rotated clockwise by a predetermined angle around the rotation axis RC, or around the rotation axis RC. Is set to one of the second states (30B (π)) indicated by a solid line rotated counterclockwise by a predetermined angle. The mirror element 30B with an oblique step is also rotated clockwise or counterclockwise to set to the first state or the second state, thereby changing the phase of incident light substantially by 0 or π. Can be reflected.

Furthermore, since the step part 31I is parallel to the direction V in the mirror element 30B of the present embodiment, the difference in reflectance can be reduced when the X-polarized or Y-polarized illumination light IL is used.
Next, the intensity and reflectance of the reflected light from the mirror element 30B of the spatial light modulator 28B of this embodiment will be quantitatively described. The result of calculation using the electric field amplitude EA of the reflected light from the mirror element 30B as a function of the rotation angle φ (deg) as a scalar value is a curve C30 in FIG. The scalar calculation formula of the electric field amplitude of the reflected light from the mirror element 30B can be expressed by the following formula (2D).

また、図８（Ａ）の曲線Ｃ３０に対応する反射光の強度Ｉは、回転角φの関数として図８（Ｂ）の曲線Ｃ３となる。しかし、図８（Ｂ）の曲線Ｃ３の最大値は０．４１となり、ミラー要素７３に対応する曲線Ｃ４の最大値０．５３よりも低く反射率を高める効果は期待できない。前述のとおり、ミラーの回転軸ＲＣから離れたところにある反射面積が広いほど反射率は高くなるが、ミラー要素３０Ｂではむしろミラーの回転軸ＲＣから離れるほど反射面積が狭くなっている。そのため、ミラー要素３０Ｂでは反射率が落ちている。ただし、上述のように、本実施形態の空間光変調器２８Ｂは、ミラー要素３０Ｂの段差部３１Ｉが照明光ＩＬの偏光方向ＰＸ又はＰＹ（Ｘ方向又はＹ方向）に対して４５°で交差する交差角となるように配置されるため、照明光ＩＬの偏光方向による反射率の相違が小さくなる利点はある。

Further, the intensity I of the reflected light corresponding to the curve C30 in FIG. 8A becomes a curve C3 in FIG. 8B as a function of the rotation angle φ. However, the maximum value of the curve C3 in FIG. 8B is 0.41, and the effect of increasing the reflectance lower than the maximum value 0.53 of the curve C4 corresponding to the mirror element 73 cannot be expected. As described above, the larger the reflection area far from the mirror rotation axis RC, the higher the reflectivity. However, in the mirror element 30B, the reflection area becomes narrower as the distance from the mirror rotation axis RC increases. Therefore, the reflectivity is lowered in the mirror element 30B. However, as described above, in the spatial light modulator 28B of the present embodiment, the step portion 31I of the mirror element 30B intersects the polarization direction PX or PY (X direction or Y direction) of the illumination light IL at 45 °. Since the crossing angles are arranged, there is an advantage that the difference in reflectance depending on the polarization direction of the illumination light IL is reduced.

The crossing angle may be larger than 0 ° and smaller than 90 °. Even in this case, the difference in reflectance depending on the polarization direction of the illumination light IL is reduced.
The shape of the mirror element 30B can be any shape other than a square as a whole.
Next, in the above embodiments, the following modifications are possible. First, in the above-described embodiment, the wafer W is continuously moved to scan and expose the wafer W. In addition, as shown in FIG. 6B, each shot area (for example, SA21) of the wafer W is divided into a plurality of partial areas SB1 to SB5 in the Y direction, and the partial areas are formed in the exposure area 26B of the projection optical system PL. When SB1 or the like reaches, the illumination light IL may be emitted by a predetermined number of pulses, and the partial region SB1 or the like may be exposed with the reflected light from the array of mirror elements 30 to 30B of the spatial light modulators 28 to 28B. . Thereafter, the wafer W is stepped in the Y direction, and after the next partial area SB2 or the like reaches the exposure area 26B, the partial area SB2 or the like is similarly exposed. This method is substantially a step-and-repeat method, but different patterns are exposed on the partial areas SB1 to SB5 and the like.

  In each of the above embodiments, the telecentric projection optical system PL is used on the object side and the image plane side. In addition, a non-telecentric projection optical system PLA can be used on the object side as shown in another example of the exposure apparatus EXA in FIG. In FIG. 21, the illumination optical system ILSA of the exposure apparatus EXA includes a main body ILSB including optical members from the light source 2 to the first relay lens 18A in FIG. 1, and a visual field to which the illumination light IL from the main body ILSB is sequentially irradiated. A diaphragm 20, a mirror 8C, a second relay lens 18B, a condenser optical system 22, and a mirror 8D are provided. The illumination optical system ILSA irradiates the array of mirror elements 30 of the spatial light modulator 28 disposed on the object plane of the projection optical system PLA with the illumination light IL at an incident angle β in the θx direction. The projection optical system PLA forms a predetermined aerial image on the surface of the wafer W by the illumination light IL reflected obliquely from the array of mirror elements 30. The incident angle β is, for example, several deg (°) to several tens deg.

In this case, since the illumination light IL incident on the array of the mirror elements 30 is inclined, the step of the step portion 31C of the mirror element 30 takes into account the incident angle β and the reflection portions 31A and 31B. The phase difference of the reflected light near the rotation axis RC is set to be π. Other configurations and operations are the same as those in the above embodiment.
Further, in place of the microlens array 16 which is the wavefront division type integrator of FIG. 1, a rod type integrator as an internal reflection type optical integrator may be used. In this case, in FIG. 1, a condensing optical system is added to the spatial light modulator 11 side of the relay optical system 14 to form a conjugate surface of the reflective surface of the spatial light modulator 11, and an incident end is provided in the vicinity of the conjugate surface. Position the rod-type integrator so that is positioned.

In addition, a relay optical system for forming an image of the illumination field stop disposed on the exit end face of the rod integrator or in the vicinity of the exit end face on the reflection surface of the spatial light modulator 28 is disposed. In this configuration, the secondary light source is formed on the pupil plane of the relay optical system 14 and the condensing optical system (a virtual image of the secondary light source is formed near the incident end of the rod integrator).
Further, when an electronic device (or micro device) is manufactured, as shown in FIG. 22, the electronic device performs step 221 for designing the function / performance of the electronic device, and forms mask pattern data based on this design step. In step 222, which is stored in the main control system of the exposure apparatuses EX, EXA, step 223, in which a substrate (wafer) which is the base material of the device is manufactured and resist is applied, and the exposure apparatuses EX, EXA (or exposure method) described above A step of exposing a spatial image of the phase distribution generated by the spatial light modulators 28, 28A, and 28B to the substrate (sensitive substrate), a step of developing the exposed substrate, a heating (curing) and etching step of the developed substrate, etc. Including substrate processing step 224, device assembly step (dicing process, bonding process, packaging process, etc. Including machining process) 225, and an inspection step 226, and the like.

This device manufacturing method includes a step of exposing the wafer W using the exposure apparatus of the above-described embodiment, and a step of processing the exposed wafer W (step 224). Therefore, an electronic device can be manufactured with high accuracy.
Further, the present invention is not limited to the application to the manufacturing process of a semiconductor device. For example, a manufacturing process such as a liquid crystal display element and a plasma display, an imaging element (CMOS type, CCD, etc.), a micromachine, a MEMS ( (Microelectromechanical systems), thin film magnetic heads, and various devices (electronic devices) such as DNA chips can be widely applied.

  In addition, this invention is not limited to the above-mentioned embodiment, A various structure can be taken in the range which does not deviate from the summary of this invention.

  EX, EXA ... exposure apparatus, ILS, ILSA ... illumination optical system, PL, PLA ... projection optical system, W ... wafer, 28, 28A, 28B ... spatial light modulator, 30, 30A, 30B ... mirror element, 32 ... base Member, 34 ... support drive unit, 48 ... modulation control unit

Claims (15)

A spatial light modulator having an array of a plurality of reflective elements,
Of the plurality of reflective elements, the first and second reflective elements are each supported rotatably around a first rotation axis,
The third reflective element different from the first and second reflective elements out of the plurality of reflective elements is rotatably supported around said first rotational shaft and the second rotation axis parallel,
Of the plurality of reflective elements, the first and second reflective elements are each at a first distance from the first rotation axis and have a first width in a direction parallel to the first rotation axis. A second portion having a second width that is greater than the first width in a direction parallel to the first rotation axis and at a second distance away from the first rotation axis from the first rotation axis. A first reflection part including two parts,
Of the plurality of reflective elements, the third reflective element is at a third distance from the second rotational axis toward the first rotational axis and has a third width in a direction parallel to the second rotational axis. A third portion having a fourth distance from the second rotation axis toward the first rotation axis , the fourth distance being greater than the third distance, and parallel to the second rotation axis. A second reflecting portion including a fourth portion having a fourth width wider than the width of the second reflecting portion,
The first reflecting portion of the first reflecting element and the first reflecting portion of the second reflecting element are disposed closer to the second rotating shaft than the first rotating shaft,
The spatial light modulator, wherein the fourth portion of the third reflective element is located between the first portion of the first reflective element and the first portion of the second reflective element. . Each of the first and second reflecting elements has a shape symmetrical to the first reflecting portion with respect to the first rotating shaft or an axis parallel to the first rotating shaft, and is integral with the first reflecting portion. And a third reflecting portion that is rotatably supported around the first rotation axis,
The third reflecting element has a shape symmetrical to the second reflecting portion with respect to the second rotating shaft or an axis parallel to the second rotating shaft, and is integrally formed with the second reflecting portion of the second rotating shaft. The spatial light modulator according to claim 1, further comprising a fourth reflecting portion that is rotatably supported around the spatial light modulator. Each of the first and second reflective elements is symmetrical to the first reflective portion with respect to the first rotational axis or an axis parallel to the first rotational axis, and is integrally formed with the first reflective portion. A third reflecting portion rotatably supported around the first rotation axis;
The spatial light modulator according to claim 1 or 2 and each of the first reflecting portion and each of the third reflecting unit and having a predetermined step. The predetermined step is reflected by the amount of change in the phase of light reflected by the portion of the first reflecting portion closest to the first rotation axis and by the portion of the third reflecting portion closest to the first rotation axis. The spatial light modulator according to claim 3 , wherein the amount of change in phase of the light to be set is set to have a phase difference of 180 °. The first reflecting portion of the first and second reflecting elements has one vertex at a portion close to the first rotation axis, and is parallel to the first rotation axis at a portion away from the first rotation axis. the spatial light modulator according to any one of claims 1 to 4, characterized in that it has a triangular shape with one side such. The first reflective portion of the first and second reflective elements has a linear portion perpendicular to the first rotational axis at a portion close to the first rotational axis, and a portion away from the first rotational axis as the first reflective portion. the spatial light modulator according to any one of claims 1 to 4, characterized in that it has a parallel linear T-shape in one rotation shaft. The first reflective portion of the first and second reflective elements is characterized in that a reflectance of a portion near the first rotation axis is smaller than a reflectance of a portion away from the first rotation axis. Item 7. The spatial light modulator according to any one of Items 1 to 6 . The first and second reflective elements have a fifth reflective part that connects the first reflective part and the third reflective part,
5. The spatial light modulator according to claim 3, wherein the fifth reflection unit includes a step at a center between the first reflection unit and the third reflection unit. The first reflecting portion of the first and second reflecting elements is in a first state rotated clockwise by a first angle around the first rotation axis and counterclockwise around the first rotation axis. The spatial light modulator according to any one of claims 1 to 8 , wherein the spatial light modulator is alternately set to a second state rotated around the same angle as the first angle. The plurality of reflecting elements are installed at positions where illumination light polarized in a direction intersecting at an intersection angle greater than 0 ° and less than 90 ° with respect to the first rotation axis is irradiated. The spatial light modulator according to any one of 1 to 9 . The spatial light modulator according to claim 10 , wherein the crossing angle is 45 °. In an exposure apparatus that exposes a substrate with exposure light via a projection optical system,
The spatial light modulator according to any one of claims 1 to 11 , which is disposed on an object plane side of the projection optical system;
An illumination system that illuminates the plurality of reflective elements of the spatial light modulator with the exposure light, and
An exposure apparatus that exposes the substrate through the projection optical system with the exposure light from the plurality of reflecting elements of the spatial light modulator. The exposure apparatus according to claim 12 , wherein the illumination system includes a polarization member that controls a polarization direction of the exposure light on a reflection surface of the plurality of reflection elements of the spatial light modulator. In accordance with a pattern to be exposed on the substrate, the plurality of reflective elements of the spatial light modulator are rotated independently from each other by a first angle clockwise around the rotation axis, and A controller that alternates between a second state rotated about the axis of rotation counterclockwise by the same angle as the first angle;
The exposure apparatus according to claim 12 , further comprising a stage that moves the substrate relative to the projection optical system. Forming a pattern of a photosensitive layer on a substrate using the exposure apparatus according to any one of claims 12 to 14 ,
Processing the substrate on which the pattern is formed;
A device manufacturing method including:

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