JP2014203905A - Illumination method and device, and exposure method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to obtain a distribution close to a target light intensity distribution in an irradiated surface even when the shape or properties of the reflecting face of the reflecting element of a spatial light modulator is changed.SOLUTION: In an illumination method for guiding illumination light from a light source to an illumination pupil face IPP via a plurality of the mirror elements 16 of a spatial light modulator 14, light from a mirror element 16A arranged in a first array area 52A of the arrangement area of the mirror elements 16 and having a reflection face that is not larger than a reference amount in terms of the amount of curve is guided to the peripheral edge areas 55Aa of partial pupil areas 55A to 55D formed on the illumination pupil face IPP. Also, light from mirror elements 16B, 16C arranged in a second array area 52B different from the first array area 52A and having a reflection face exceeding the reference amount in terms of the amount of curve is guided to the inside areas 55Ab of the partial pupil areas 55A to 55D.

Description

  The present invention relates to an illumination technique for illuminating an irradiated surface, an exposure technique using the illumination technique, and a device manufacturing technique using the exposure technique.

  For example, an exposure apparatus such as a stepper or a scanning stepper used in a lithography process for manufacturing an electronic device (microdevice) such as a semiconductor element includes an illumination device for illuminating a reticle (mask) under various illumination conditions. ing. As a recent illuminating device, in order to optimize the light intensity distribution on the pupil plane (surface conjugate with the exit pupil) of the illumination optical system to various distributions according to the pattern of the reticle, a large number of variable tilt angles can be used. A type including an intensity distribution setting optical system using a movable multi-mirror spatial light modulator having minute mirror elements has also been proposed (see, for example, Patent Document 1).

US Patent Application Publication No. 2003/0038225

  Conventionally, it has been assumed that the shape of the reflecting surface of the mirror element of the spatial light modulator is flat. However, if exposure is continued in the exposure apparatus, some of the mirror elements of the spatial light modulator whose shape of the reflecting surface is deformed into a convex shape or a concave shape due to a change with time due to the irradiation energy of the exposure light appears. There is a fear. In this way, the reflected light from the mirror element whose shape of the reflecting surface is no longer flat may spread the irradiation area on the pupil plane of the illumination optical system. For this reason, if such a mirror element is used as it is, there is a possibility that a target light intensity distribution cannot be obtained on the pupil plane.

  In view of such circumstances, the aspect of the present invention provides a distribution close to the target light intensity distribution on the irradiated surface even when the shape or properties of the reflecting surface of the reflecting element of the spatial light modulator changes. The purpose is to do so.

  According to the first aspect of the present invention, in an illumination method for guiding light from a light source to an irradiated surface via a plurality of reflecting elements included in a spatial light modulator, the arrangement region in which the plurality of reflecting elements are arranged And guiding the light from the reflective element having the first reflective surface shape disposed in the first region to the second region formed on the irradiated surface, and a third different from the first region Light from a reflective element that is arranged in a region and has a second reflective surface shape different from the first reflective surface shape is guided to a fourth region that is different from the second region formed on the irradiated surface. And a lighting method is provided.

  According to the second aspect, in the illumination method for guiding the light from the light source to the irradiated surface via the plurality of reflecting elements included in the spatial light modulator, it relates to the surface shape of the reflecting surface of the plurality of reflecting elements. Providing an illumination method comprising: detecting a physical quantity; and adjusting light guided from the plurality of reflective elements to the illuminated surface based on the detected physical quantity associated with the surface shape of the reflective surface Is done.

According to the third aspect, in the exposure method of illuminating the pattern with the light from the exposure light source and exposing the substrate with the light from the exposure light source through the pattern and the projection optical system, the illumination method according to the aspect of the present invention Is used to illuminate the pattern with light from the exposure light source.
According to the fourth aspect, in the illumination device that includes the spatial light modulator having the plurality of reflection elements and guides the light from the light source to the irradiated surface, the first of the arrangement regions in which the plurality of reflection elements are arranged. The light from the reflective element having the first reflecting surface shape arranged in one area is guided to the second area formed on the irradiated surface, and is arranged in the third area different from the first area. The plurality of light beams are guided so as to guide light from a reflecting element having a second reflecting surface shape different from the first reflecting surface shape to a fourth region different from the second region formed on the irradiated surface. An illuminating device is provided that includes a control device that controls the reflective elements of the device.

According to the fifth aspect, in the exposure apparatus that illuminates the pattern with the light from the exposure light source and exposes the substrate through the pattern and the projection optical system with the light from the exposure light source, the illumination apparatus according to the aspect of the present invention There is provided an exposure apparatus that illuminates the pattern with light from the exposure light source using the illumination apparatus.
According to a sixth aspect, the method includes forming the pattern of the photosensitive layer on the substrate using the exposure method or the exposure apparatus of the aspect of the present invention, and processing the substrate on which the pattern is formed. A device manufacturing method is provided.

  According to the aspect of the present invention, the shape or property of the reflecting surface of the mirror element is changed by adjusting the light guided from the reflecting element to the irradiated surface according to the reflecting surface shape of the reflecting element of the spatial light modulator. Even in this case, a distribution close to the target light intensity distribution can be obtained on the irradiated surface.

It is a figure which shows schematic structure of the exposure apparatus which concerns on 1st Embodiment. FIG. 2A is an enlarged perspective view showing a part of a mirror element array of the spatial light modulator in FIG. 1, and FIG. 2B is a view showing a drive mechanism of one mirror element in FIG. (A) is a diagram showing a simplified portion of the illumination optical system in FIG. 1, (B) is a diagram showing the light receiving surface of the image sensor in FIG. 3 (A), and (C) is another example of a beam spot. (D) is a figure which shows the array of the mirror element of a spatial light modulator. It is a flowchart which shows an example of the exposure method containing the illumination method. It is a figure which shows in which position of the partial pupil area | region of the reflected light from the several mirror element of a spatial light modulator in the entrance plane (illumination pupil plane) of a fly-eye lens. (A) is a figure which shows the principal part of the exposure apparatus which concerns on 2nd Embodiment, (B) is a figure which shows the state in which a divergent light injects into a some mirror element, (C) is a divergent light to a some mirror element. It is a figure which shows the state in which convergent light injects. FIG. 6A is a diagram showing a part of the illumination optical system in FIG. 6A in a simplified manner, FIG. 6B is a diagram showing a light receiving surface of the image sensor in FIG. 7A, and FIG. It is a figure which shows the state in which convergent light injects into an element. It is a flowchart which shows an example of the manufacturing process of an electronic device.

[First Embodiment]
A first embodiment of the present invention will be described with reference to FIGS.
FIG. 1 shows a schematic configuration of an exposure apparatus EX according to the present embodiment. The exposure apparatus EX is, for example, a scanning exposure type exposure apparatus (projection exposure apparatus) composed of a scanning stepper (scanner). In FIG. 1, the exposure apparatus EX includes an illumination apparatus 8 that illuminates a reticle surface Ra, which is a pattern surface of a reticle R (mask), with exposure illumination light (exposure light) IL. The illumination device 8 includes a light source 10 that generates a pulse of illumination light IL, an illumination optical system ILS that illuminates the reticle surface Ra with the illumination light IL from the light source 10, an illumination control unit 36 that controls illumination conditions, and the like. A storage device 33 connected to the control unit 36 and a pupil monitor system 23 and a determination unit 34 described later are provided. The exposure apparatus EX further includes a reticle stage RST that moves the reticle R, a projection optical system PL that projects an image of the pattern of the reticle R onto the surface of the wafer W (substrate), a wafer stage WST that moves the wafer W, A main control system 35 composed of a computer that comprehensively controls the operation of the entire apparatus and various control systems are provided.

  Hereinafter, the Z axis is set in parallel to the optical axis AX of the projection optical system PL, the X axis is set in a direction parallel to the paper surface of FIG. 1 in a plane perpendicular to the Z axis, and the Y axis is set in a direction perpendicular to the paper surface of FIG. An explanation will be given by setting an axis. In the present embodiment, the scanning direction of the reticle R and the wafer W during exposure is a direction parallel to the Y axis (Y direction). In addition, the rotational directions (inclination directions) around the axes parallel to the X axis, the Y axis, and the Z axis will be described as the θx direction, the θy direction, and the θz direction.

  As the light source 10, for example, an ArF excimer laser light source that emits a pulse of linearly polarized laser light having a wavelength of 193 nm is used. As the light source 10, a KrF excimer laser light source that supplies a laser beam with a wavelength of 248 nm, or a harmonic generator that generates a harmonic of a laser beam output from a solid-state laser light source (YAG laser, semiconductor laser, etc.) is also available. Can be used.

  In FIG. 1, illumination light IL emitted from a light source 10 includes a transmission optical system including a beam expander 11, a polarization optical system 12 for adjusting the polarization direction and polarization state of the illumination light IL, and an optical path bending mirror. 13, the spatial light modulator (SLM) 14 is incident obliquely at a predetermined small incident angle on the reflecting surface of a large number of minute mirror elements 16 having variable inclination angles around two orthogonal axes. To do. The illumination light IL becomes a substantially parallel light beam by the beam expander 11 and is incident on a rectangular irradiation region 50 (see FIG. 3D) elongated in the X direction, for example, on the array of mirror elements 16. The spatial light modulator 14 (hereinafter referred to as SLM 14) has an array of a large number of mirror elements 16 and a drive substrate portion 15 that supports and drives each mirror element 16. Hereinafter, the tilt angle around the two axes of the mirror element 16 (so-called tilt angle) is also simply referred to as the angle of the mirror element 16. The angle of each mirror element 16 is controlled by the SLM control system 17.

The reflecting surfaces of all the mirror elements 16 of the SLM 14 are planes inclined at a small angle with respect to the ZY plane (hereinafter referred to as arrangement surfaces) when the tilt angle of the mirror elements 16 is 0 (or in a power-off state). It is installed in RP. Immediately after the manufacture of the exposure apparatus EX equipped with the SLM 14 or at the start of operation, the reflecting surface of each mirror element 16 is flat (flat).
FIG. 2A is an enlarged perspective view showing a part of the SLM 14. In FIG. 2 (A), an array of a large number of mirror elements 16 arranged close to each other at a constant pitch in the Y direction and the Z direction is supported on the surface of the drive substrate portion 15 of the SLM 14.

  As shown in FIG. 2B, the drive mechanism of the mirror element 16 includes, as an example, a hinge member 43 that supports the mirror element 16 via a support column 41, a support substrate 44, and a hinge member 43 on the support substrate 44. Four insulating support members 42 to be supported and four electrodes 45A, 45B, 45C and 45D formed on the support substrate 44 are provided. The number of mirror elements 16 is, for example, several thousand to several hundred thousand. In this configuration example, the mirror element 16 is made of a metal such as aluminum, and all the mirror elements 16 are grounded via a common signal line (not shown). Further, a variable driving voltage continuously applied within a predetermined range is applied to the four electrodes 45A to 45D of the mirror element 16 by an SLM control system 17 via individual signal lines (not shown).

  By controlling the driving voltage of the electrodes 45A to 45D facing each mirror element 16 individually and controlling the potential difference between each mirror element 16 and the electrodes 45A to 45D facing each mirror element 16, via the hinge member 43 Thus, the support column 41 supported flexibly can be swung and inclined. Thereby, the inclination angle around two orthogonal axes of the reflecting surface of each mirror element 16 fixed to the support column 41 can be continuously controlled within a predetermined variable range.

  The array of mirror elements 16 provided on the drive substrate unit 15 and these drive mechanisms can be manufactured using, for example, MEMS (Microelectromechanical Systems) technology. Further, as the spatial light modulator having the array of mirror elements 16, for example, those disclosed in European Patent Publication No. 779530 or US Pat. No. 6,900,915 can be used. . Although the mirror element 16 is a substantially square plane mirror, the shape thereof may be any shape such as a rectangle or a circle.

  In FIG. 1, the SLM 14 forms a predetermined light intensity distribution (light quantity distribution) on an incident surface 25I of a fly-eye lens 25 described later via a large number of mirror elements 16 according to illumination conditions. The positions around the two orthogonal axes of each mirror element 16 define the positions (incident positions) in the Y direction and Z direction of the center of the irradiation area on the incident surface 25I of the light reflected by the mirror element 16. The relationship between the angle of each mirror element 16 and the incident position of the reflected light on the incident surface 25 </ b> I is stored in the storage device 33 and input to the illumination control unit 36. The main control system 35 supplies the illumination condition information for the reticle R to the illumination control unit 36, and the illumination control unit 36 controls the angle of each mirror element 16 of the SLM 14 via the SLM control system 17 in response thereto.

  The illumination light IL reflected by the many mirror elements 16 of the SLM 14 enters the incident optical system 18 that converts the illumination light IL into substantially parallel light along the optical axis AXI of the illumination optical system ILS. The incident optical system 18 also has a function of forming a distribution similar to the light intensity distribution formed on the incident surface 25I on the surface between the incident surface 25I and the incident optical system 18. The illumination light IL that has passed through the incident optical system 18 enters the incident surface 25I of the fly-eye lens 25 via the relay optical system 24 including the first lens system 24a and the second lens system 24b. The fly-eye lens 25 has a large number of lens elements arranged in close contact with each other in the Z direction and the Y direction, and the exit surface of the fly-eye lens 25 is the pupil plane of the illumination optical system ILS (hereinafter referred to as the illumination pupil plane). ) IPP. The illumination pupil plane IPP is optically conjugate with the plane on which the exit pupil of the illumination optical system ILS is formed. A surface light source including a large number of secondary light sources (light source images) is formed on the exit surface (illumination pupil plane IPP) of the fly-eye lens 25 by wavefront division.

  Since the fly-eye lens 25 has a large number of optical systems arranged in parallel, the global light intensity distribution on the entrance surface 25I is directly transmitted to the illumination pupil plane IPP which is the exit surface. In other words, there is a high correlation between the global light intensity distribution formed on the incident surface 25I and the global light intensity distribution of the entire secondary light source. For this reason, the arbitrary light intensity distribution of the illumination light IL formed on the entrance surface 25I becomes the light intensity distribution on the illumination pupil plane IPP almost as it is, and the entrance surface 25I is a plane equivalent to the illumination pupil plane IPP. The incident surface 25I is substantially spatially Fourier-transformed with respect to the arrangement surface RP of the mirror element 16 by an optical system (optical or spatial Fourier transform optical system) comprising the incident optical system 18 and the relay optical system 24. Are in a relationship.

A micro fly's eye lens may be used instead of the fly's eye lens 25. Further, as the fly eye lens, for example, a cylindrical micro fly eye lens disclosed in US Pat. No. 6,913,373 may be used.
Further, a beam splitter 19 is installed between the first lens system 24 a and the second lens system 24 b, and the light beam branched by the beam splitter 19 from the illumination light IL passes through the condenser lens 20 and is a CCD or CMOS type 2. The light is incident on the light receiving surface of the two-dimensional image sensor 22. The detection surface HP on which the light receiving surface of the image sensor 22 is arranged is optically conjugate or almost conjugate with the incident surface 25I of the fly-eye lens 25 by the condenser lens 20. In other words, the detection surface HP is also a surface equivalent to the illumination pupil plane IPP. A pupil monitor system 23 is configured including the beam splitter 19, the condenser lens 20, and the image sensor 22. By processing the image pickup signal of the image pickup element 22 by a processing circuit (not shown), the light intensity distribution on the incident surface 25I, and hence the light intensity distribution on the illumination pupil plane IPP can be measured. The measurement result is supplied to the determination unit 34. When measuring the deflection amount of the mirror element 16 of the SLM 14 (details will be described later), the determination unit 34 determines the state of the deflection amount of each mirror element 16 of the SLM 14 from the supplied light intensity distribution, and the determination result is used as the illumination control unit 36. To supply. In other cases, the determination unit 34 supplies the supplied light intensity distribution to the illumination control unit 36 as it is. Note that the determination unit 34 and the illumination control unit 36 may be functions on software of a computer.

  Illumination light IL from the surface light source formed on the illumination pupil plane IPP includes a first relay lens 28, a reticle blind (field stop) 29, a second relay lens 30, an optical path bending mirror 31, and a condenser optical system. The illumination area of the reticle surface Ra is illuminated with a uniform illuminance distribution via the reference numeral 32. The reticle blind 29 has a fixed blind and a movable blind that opens and closes during scanning exposure. The illumination optical system ILS is configured to include the optical members from the beam expander 11 to the SLM 14, the incident optical system 18, the relay optical system 24, the pupil monitor system 23, and the optical system from the fly-eye lens 25 to the condenser optical system 32. ing. Each optical member of the illumination optical system ILS is supported by a frame (not shown).

  Under the illumination light IL from the illumination optical system ILS, the pattern in the illumination area of the reticle R is transferred to one shot area of the wafer W via the telecentric projection optical system PL on both sides (or one side on the wafer side). The image is projected onto the exposure area at a predetermined projection magnification (for example, 1/4, 1/5, etc.). An aperture stop AS is provided on or near the pupil plane (hereinafter referred to as the projection pupil plane) PLP of the projection optical system PL. The projection pupil plane PLP is optically conjugate with the illumination pupil plane IPP. The wafer W (substrate) includes a substrate in which a photoresist (photosensitive material) is applied with a predetermined thickness on the surface of a base material such as silicon.

  The reticle R is attracted and held on the upper surface of the reticle stage RST, and the reticle stage RST is movable on the upper surface of the reticle base (not shown) (surface parallel to the XY plane) at a constant speed in the Y direction, and at least X It is mounted so as to be movable in the direction, the Y direction, and the θz direction. The two-dimensional position of the reticle stage RST is measured by a laser interferometer (not shown). Based on this measurement information, the main control system 35 receives the position and speed of the reticle stage RST via a drive system 37 including a linear motor and the like. To control.

  On the other hand, wafer W is sucked and held on the upper surface of wafer stage WST via a wafer holder (not shown), and wafer stage WST is placed on the upper surface (surface parallel to the XY plane) (not shown) in the X direction, Y direction, And move in the θz direction and move in the Y direction at a constant speed. The two-dimensional position of wafer stage WST is measured by an unillustrated laser interferometer and / or an encoder device using a diffraction grating, and based on this measurement information, main control system 35 has a drive system 38 including a linear motor or the like. And controls the position and speed of wafer stage WST. An alignment system (not shown) for aligning the reticle R and the wafer W is also provided.

  In the present embodiment, the wafer stage WST is provided with an aperture measurement system 39 for monitoring the light intensity distribution on the projection pupil plane PLP. The configuration of the aperture measurement system 39 is the same as that of the condenser lens 20 and the image sensor 22 of the pupil monitor system 23. In a state where the reticle R is not placed on the reticle stage RST, the aperture measurement system 39 is moved to the exposure area of the projection optical system PL and irradiated with the illumination light IL from the illumination optical system ILS. Thus, the light intensity distribution on the projection pupil plane PLP, and hence the light intensity distribution on the illumination pupil plane IPP can be measured. The measurement result is supplied to the illumination control unit 36. Instead of the aperture measurement system 39 fixed to the wafer stage WST, a detachable aperture measurement system provided on the wafer stage WST or the reticle stage RST can also be used.

  At the time of exposure of the wafer W by the exposure apparatus EX, the main control system 35 reads the illumination condition (here, the light intensity distribution on the illumination pupil plane IPP) determined according to the pattern of the reticle R from the exposure data file in the internal storage device. And the read illumination condition is set in the illumination control unit 36. The illumination control unit 36 individually controls the angle of each mirror element 16 of the SLM 14 via the SLM control system 17. Actually, the illumination condition includes the polarization state of the illumination light IL, and the main control system 35 sets the polarization state of the illumination light IL via the polarization optical system 12. Subsequently, the wafer W is moved to the scanning start position by the movement (step movement) of the wafer stage WST. Thereafter, light emission of the light source 10 is started, the reticle R is illuminated with the illumination light IL from the illumination optical system ILS, and the wafer W is exposed with an image of the projection optical system PL of the pattern of the reticle R, while the reticle stage RST and By moving the reticle R and the wafer W in synchronism with the Y direction using the projection magnification as a speed ratio via the wafer stage WST, a pattern image of the reticle R is scanned and exposed on one shot area of the wafer W. In this way, the image of the pattern of the reticle R is exposed on the entire shot area of the wafer W by the step-and-scan operation in which the step movement of the wafer W and the scanning exposure are repeated. Note that the scanning direction of the reticle R and the wafer W may be the X direction in FIG.

  When such exposure is continued, the shape of the reflecting surface in the many mirror elements 16 of the SLM 14 is bent into a convex shape or a concave shape due to, for example, a change with time due to the integrated irradiation energy of the illumination light IL. There is a risk that something will deform. FIG. 3D shows an illumination light irradiation region 50 set on the array of mirror elements 16 of the SLM 14. In the irradiation area 50, particularly in the central elliptical area 52, the light intensity of the illumination light may increase on average. In such a case, the mirror element 16 in the area 52 and the area in the vicinity thereof may be more easily bent than the mirror elements 16 in other areas. In the following, the shape of the reflecting surface of the mirror element 16 being convex (or concave) means convex (or concave) when viewed from the direction of reflected light.

  FIG. 3A shows a simplified portion of the illumination optical system ILS in FIG. 1, and FIG. 3B shows a light receiving portion 22a of the image sensor 22 of the pupil monitor system 23 in FIG. Show. In FIG. 3A, the incident optical system 18, the relay optical system 24, and the condensing optical system 20 of FIG. 1 are represented by one incident optical system 26. In FIG. 3B, a large number of pixels 22b are arranged at a predetermined pitch in the X and Y directions in the light receiving portion 22a. An area EA (hereinafter referred to as an effective area) EA surrounded by a dotted circle on the light receiving unit 22a is an area where light branched from a light beam that can pass through the fly-eye lens 25 is incident. In FIG. 3A, the reflecting surfaces of the mirror elements 16A, 16B, and 16 of the SLM 14 are a flat surface, a concave surface, and a convex surface, respectively. At this time, since the illumination light IL incident on the mirror elements 16A to 16C is a substantially parallel light beam, the reflected light ILA from the mirror element 16A is the smallest on the incident surface 25I of the fly-eye lens 25, and hence on the illumination pupil plane IPP. It is focused on the beam spot (incident area). At this time, a light beam ILA1 branched from the reflected light ILA by the beam splitter 19 forms the smallest, for example, substantially circular beam spot BSA1 (see FIG. 3B) in the light receiving unit 22a.

  On the other hand, the reflected light ILB from the mirror element 16B bent into a concave shape is once condensed by the incident optical system 26 and then spread to a certain extent on the incident surface 25I (illumination pupil plane IPP) (incident region). ). Further, the reflected light ILC from the mirror element 16C bent in a convex shape is incident on a beam spot that is spread to some extent on the incident surface 25I (illumination pupil plane IPP) via the incident optical system 26. At this time, beam spots BSB1 and BSC1 (see FIG. 3B) that are spread to some extent on the light receiving portion 22a of the image sensor 22 are formed by the lights ILB1 and ILC1 branched from the reflected lights ILB and ILC. Accordingly, when the beam spot BSA1 or the like is circular, if the diameter thereof is the size, the minimum value dm of the size (size) d of the beam spots BSA1 to BSC1 (for example, at the start of operation of the exposure apparatus EX). It can be considered that the deviation δd from the measured value) and the deflection amount of the corresponding mirror elements 16A to 16C are substantially proportional. In other words, the deviation δd is a physical quantity related to the surface shape of the corresponding mirror element 16.

  The determination unit 34 of the present embodiment obtains the size d of the beam spots BSA1 to BSC1 from the light intensity distribution detected by the image sensor 22, and the deviation between the obtained size d and the minimum value dm measured in advance. As an example, when the deviation δd exceeds a predetermined reference value ds, it is determined that the deflection amount of the mirror element 16 corresponding to the beam spot is larger than the reference amount. For example, when the size d of the beam spots BSB1 and BSC1 exceeds twice the minimum value dm, it can be determined that the amount of deflection of the corresponding mirror elements 16B and 16C is large. In this case, the reference value ds is the same as the minimum value dm.

  The beam spots BSA1 to BSC1 actually have a light intensity distribution in which the intensity gradually decreases in the radial direction. For this reason, even if the widths (or pitches) px and py in the X direction and Y direction of the pixel 22b of the image sensor 22 are larger than the minimum value of the size d (for example, half-value width) of the beam spot BSA1, the pixels 22b By interpolating the detected light intensity, it is possible to obtain the light intensity distribution of the beam spots BSA1 to BSC1, and hence the size d thereof. Further, a value obtained by multiplying the reciprocal of the light intensity detected by the pixel 22b at the center of the beam spots BSA1 to BSC1 by a predetermined coefficient may be regarded as the size of the corresponding beam spots BSA1 to BSC1. is there. Further, although the beam spot BSA1 and the like in FIG. 3B are circular, depending on the size of the mirror element 16, the beam spot BSA1 and the like can be regarded as a substantially square shape as shown in FIG. In some cases. In this case, the size d of the beam spot BSA1 can be the width of the square region.

  Next, in the exposure apparatus EX of the present embodiment, an example of an operation of measuring the amount of deflection of each mirror element 16 of the SLM 14 and illuminating the reticle while driving the SLM 14 based on the measurement result to expose the wafer. This will be described with reference to the flowchart of FIG. This operation is controlled by the main control system 35. First, in step 102 in FIG. 4, the deflection amount of the reflecting surfaces of all the mirror elements 16 of the SLM 14 in FIG. 1 is determined for each mirror element on the image sensor 22 of the pupil monitor system 23 of the reflected light from each mirror element 16. Measured from the beam spot size d of the reflected light from 16. Therefore, as an example, the illumination control unit 36 divides the array of the mirror elements 16 of the SLM 14 into N measurement areas (N is an integer of 2 or more), and the plurality of mirror elements 16 in the first measurement area. The reflected light is incident on a beam spot centered on a plurality of measurement points set in a lattice pattern within the effective area EA (see FIG. 3B) of the imaging device 22 of the pupil monitor system 23. Set to. At this time, the angles of the mirror elements 16 that are not measurement targets are set so that, for example, the reflected light enters the area outside the effective area EA and becomes discarded light. Information on the position of the mirror element 16 to be measured is also supplied to the determination unit 34.

  Then, using the light intensity distribution detected by the image sensor 22 by causing the light source 10 to emit light, the determination unit 34 determines the beam spot size d and deviation δd (known minimum value dm) around each measurement point. Difference). Then, the determination unit 34 supplies information on the position of the mirror element 16 corresponding to the measurement point whose deviation δd exceeds a predetermined reference value ds to the illumination control unit 36. The illumination control unit 36 can recognize that the amount of deflection of the reflecting surface of the mirror element 16 at the supplied position exceeds the reference amount. Similarly, with respect to the plurality of mirror elements 16 in the second to Nth measurement areas of the SLM 14, whether or not the deflection amount of the reflecting surface sequentially exceeds the reference amount is measured.

  In the next step 104, the illumination control unit 36 uses the first array region 52A in which the mirror elements 16 of the SLM 14 are arranged in the first array region 52A in which the mirror elements 16 whose reflection surface deflection amount is equal to or less than the reference amount are arranged as shown in FIG. And the second array region 52A in which the mirror elements 16 in which the deflection amount of the reflecting surface exceeds the reference amount are arranged. In FIG. 5, as an example, the second array region 52 </ b> A in which the mirror elements 16 having the deflection amount exceeding the reference amount are arranged into the region 52 having a high light intensity in the irradiation region 50 of the illumination light IL of FIG. The corresponding central area. In some cases, the first array region 52A and the second array region 52B may be complicated sections composed of a plurality of partial regions.

  In the next step 106, the main control system 35 reads the illumination condition of the reticle R (here, information on the light intensity distribution on the illumination pupil plane IPP), and sets the read illumination condition in the illumination control unit 36. As an example, the illumination conditions of the reticle R are 4 arranged in the Z direction and the Y direction with the optical axis AXI as the center on the illumination pupil plane IPP (or the entrance surface 25I of the fly-eye lens 25) as shown in FIG. It is assumed that the illumination is quadrupole illumination having a light intensity distribution 54 in which the light intensity of one region (hereinafter referred to as a partial pupil region) 55A, 55B, 55C, and 55D increases. In FIG. 5, a dotted circumference 56 indicates a portion having a coherence factor (σ value) of 1, and an inside of the dotted circle 57 indicates a region where a light beam can pass through the fly-eye lens 25. Thereafter, reticle R is loaded on reticle stage RST, and alignment of reticle R is performed.

  In the next step 108, the illumination control unit 36 reflects the reflected light from the plurality of mirror elements 16 (mirror elements whose deflection amount is a reference amount or less) in the first array region 52A of the SLM 14 into the partial pupil of the illumination pupil plane IPP. Reflected light from the plurality of mirror elements 16 (mirror elements whose deflection amount exceeds the reference amount) in the second array region 52B of the SLM 14 is incident on the peripheral region 55Aa of the regions 55A to 55D and the partial pupil region 55A. The angle of each mirror element 16 is set so as to be incident on an inner region (inner or central region) 55Ab or the like of the region 55Aa at the peripheral edge of ~ 55D.

  In the present embodiment, the size of the beam spot BSA formed in the region 55Aa of the illumination pupil plane IPP by the reflected light from the mirror element 16A of the first array region 52A is the mirror element 16B (or 16C) of the second array region 52B. Is smaller than the size of the beam spot BSB (or BSC) formed in the region 55Ab of the illumination pupil plane IPP. For this reason, even when a mirror element whose deflection amount exceeds the reference amount appears in the plurality of mirror elements 16 of the SLM 14, the contours or edges of the partial pupil regions 55A to 55D (irradiated regions) can be clearly defined (edges). Can be accurately set to the target position), and the illumination condition (light intensity distribution of the illumination pupil plane IPP) can be set to the target state with high accuracy.

  In the next step 110, the unexposed wafer W coated with the photoresist is loaded onto the wafer stage WST and alignment is performed. Then, emission of the illumination light IL from the light source 10 is started, and the reflected light from the mirror elements 16A and 16B (16C) of the first and second array regions 52A and 52B of the SLM 14 is applied to the illumination pupil plane IPP in FIG. A light intensity distribution 54 is formed. Thereafter, in step 112, the wafer W is scanned and exposed by the illumination light IL through the reticle R and the projection optical system PL. Thereafter, the emission of the illumination light IL from the light source 10 is stopped. When the next wafer is exposed, steps 110 and 112 are repeated.

  The measurement of the deflection amount of the mirror element 16 in step 102 and the classification of the array of mirror elements 16 in step 104 based on the measurement result are performed, for example, periodically. According to the exposure method including this illumination method, when a mirror element whose deflection amount exceeds the reference amount appears in the plurality of mirror elements 16 of the SLM 14, the position of the mirror element whose deflection amount exceeds the reference amount is specified. Then, the reflected light from the mirror element whose deflection amount exceeds the reference amount is guided to the region 55Ab or the like inside the partial pupil regions 55A to 55D of the illumination pupil plane IPP. For this reason, the reticle R can always be illuminated in a state close to the target illumination condition, and the pattern image of the reticle R can be exposed onto the wafer W with high accuracy.

  As described above, the exposure apparatus EX according to the present embodiment includes the SLM (spatial light modulator) 14 having a plurality of mirror elements 16 (reflection elements), and converts the illumination light IL from the light source 10 into the incident surface 25 and the illumination pupil. An illuminating device 8 that leads to a surface IPP (irradiated surface) is provided. In addition, the illumination device 8 includes an illumination control unit 36 (control device) that controls an angle around two orthogonal axes of the plurality of mirror elements 16. And the illumination control part 36 is arrange | positioned in the 1st array area | region 52A (1st area | region) of the array (arrangement area | region) of the mirror element 16, and the amount of deflection | deviation is below a reference amount (1st near flat 1st). The light from the mirror element 16A having the (reflecting surface shape) is guided to the peripheral area 55Aa (second area) formed on the illumination pupil plane IPP, and is arranged in the second array area 52B (third area). An inner (center) region in which light from the mirror elements 16B and 16C having a reflecting surface (second reflecting surface shape such as a concave shape or a convex shape) whose deflection amount exceeds a reference amount is formed on the illumination pupil plane IPP The angle of each mirror element 16 is controlled so as to lead to 55 Ab (fourth region).

In the illumination method using the illumination device 8, the light from the mirror element 16A arranged in the first array region 52A is guided to the peripheral region 55Aa formed on the illumination pupil plane IPP, and also to the second array region 52B. Steps 108 and 110 are provided for guiding light from the arranged mirror elements 16B and 16C to an inner region 55Ab (fourth region) formed on the illumination pupil plane IPP.
According to the present embodiment, the irradiation position of the light guided from the plurality of mirror elements 16 to the illumination pupil plane IPP is determined based on the shape of the reflection surface (reflection surface shape) of the plurality of mirror elements 16 of the SLM 14. Alternatively, even when the shape of the reflecting surface of the mirror element 16 (surface shape or properties such as bending) is changed by adjusting to the inner region 55Ab, a distribution close to the target light intensity distribution is obtained on the illumination pupil plane IPP. can get.

Further, even when the shape of the reflecting surface of the mirror element 16 is changed, the reflected light from the mirror element 16 whose shape of the reflecting surface is changed is not discarded (light that does not enter the fly-eye lens 25). Since it can be used effectively, the utilization efficiency of the illumination light IL can be maintained high while setting the illumination conditions with high accuracy.
Even when the shape of the reflecting surface of the mirror element 16 changes, a desired light intensity distribution (pupil distribution) can be formed on the illumination pupil plane IPP.

  The exposure apparatus EX of the present embodiment illuminates the reticle R pattern with the illumination light IL from the exposure light source 10, and the illumination light IL illuminates the wafer W (substrate) via the pattern and the projection optical system PL. In the exposure apparatus that performs exposure, the pattern is illuminated with the illumination light IL from the light source 10 using the illumination apparatus 8 of the present embodiment. Therefore, according to the exposure apparatus EX or the exposure method using the exposure apparatus EX, the reticle R can always be illuminated under conditions close to the target illumination conditions, so that the image of the pattern on the reticle R can be exposed onto the wafer W with high accuracy.

In the present embodiment, the following modifications are possible.
First, in the present embodiment, the reflected light from the mirror elements 16B and 16C whose deflection amount of the reflecting surface exceeds the reference amount is guided to the region 55Ab and the like inside the partial pupil regions 55A to 55D of the illumination pupil plane IPP. When the ratio of the mirror elements 16B and 16C whose deflection amount exceeds the reference amount is small, the reflected light from these mirror elements 16B and 16C does not enter the fly-eye lens 25 (for example, in FIG. 5). It is good also as the abandoned light which advances to the area | region 58A, 58B outside the area | region 57). Thereby, the illumination condition can be set with high accuracy.

In this embodiment, the amount of deflection of the reflecting surface of the mirror element 16 is evaluated in two stages, but the amount of deflection may be evaluated in three stages or more. As an example, when the deflection amount is evaluated in three stages, the reflected light from the mirror element 16 having the largest deflection amount may be discarded.
In this embodiment, since the amount of deflection of each mirror element 16 of the SLM 14 is measured in step 102, the reflected light from the mirror element 16 can be used properly according to the amount of deflection. However, as described with reference to FIG. 3D, when the light intensity of the central region 52 of the irradiation region 50 of the illumination light IL with respect to the array of the mirror elements 16 of the SLM 14 is high, the region 52 or Nearby mirror elements 16 may be easily deflected. In this case, the measurement process in step 102 is omitted, and as an example, after a period of time has elapsed since the exposure apparatus EX started to operate, in step 104, the central area 52 and the area in the vicinity thereof are moved to the second array. As a region, the reflecting surfaces of the plurality of mirror elements 16 in the second array region may be considered to be bent to an extent exceeding a reference amount. Then, by guiding the reflected light from the plurality of mirror elements 16 in the second array region to the region 55Ab or the like in the partial pupil regions 55A to 55D of the illumination pupil plane IPP, the region 52 or its vicinity is actually Even when the mirror element 16 in the region is bent, the illumination condition can be maintained with high accuracy.

Further, in this embodiment, quadrupole illumination is used, but as an illumination condition, a light intensity distribution in which light intensity increases in a circular area, an annular area, a dipole area, or the like on the illumination pupil plane IPP. The illumination method of the present embodiment can also be applied when using any illumination condition that uses.
Further, in this embodiment, the beam spot of the reflected light from the mirror element 16 is measured using the pupil monitor system 23, but an aperture measurement system 39 may be used instead of the pupil monitor system 23.

[Second Embodiment]
A second embodiment of the present invention will be described with reference to FIGS. 6 (A) to 7 (C). 6 (A), FIG. 7 (A), and FIG. 7 (B), parts corresponding to FIG. 1, FIG. 3 (A), and FIG. Detailed description thereof is omitted.
FIG. 6A shows a main part including the illumination device 8A of the exposure apparatus EXA according to the present embodiment. 6A, the illumination device 8A includes an illumination optical system ILSA, and the illumination optical system ILSA includes a micro fly's eye lens 25A instead of the fly eye lens 25 of FIG. The micro fly's eye lens 25A is, for example, an optical element made up of a large number of microlenses having positive refractive power arranged vertically and horizontally and densely. The microflyeye lens 25A is constituted by forming a group of microlenses by etching a plane parallel plate. Has been. In a micro fly's eye lens, unlike a fly eye lens composed of lens elements isolated from each other, a large number of micro lenses (micro refractive surfaces) are integrally formed without being isolated from each other. However, the micro fly's eye lens is the same wavefront division type optical integrator as the fly's eye lens in that the lens elements are arranged vertically and horizontally.

  A rectangular minute refracting surface as a unit wavefront dividing surface in the micro fly's eye lens 25A is similar to the shape of the illumination field to be formed on the reticle R (mask) (and thus the shape of the exposure region to be formed on the wafer W). A rectangular shape. As the micro fly's eye lens 25A, for example, a cylindrical micro fly's eye lens can be used. The configuration and operation of the cylindrical micro fly's eye lens are disclosed in, for example, the above-mentioned US Pat. No. 6,913,373.

  Also in the present embodiment, the incident surface 25AI of the micro fly's eye lens 25A is equivalent to the illumination pupil plane IPP. The beam expander 11 in the illumination optical system ILSA includes a first lens 11a and a second lens 11b. As an example, the second lens 11b can be moved along the optical axis by the drive unit DRV1. The illumination control unit 36 moves the second lens 11b along the optical axis via the driving unit DRV1, so that the array of mirror elements 16 of the SLM 14 passes through the beam expander 11, the polarization optical system 12, and the mirror 13. The incident illumination light IL can be set to any state of a parallel light beam, a divergent light indicated by a dotted optical path A2, or a convergent light (converged light). Other configurations are the same as those of the exposure apparatus EX of the first embodiment.

  FIG. 7A shows a simplified portion of the illumination optical system ILSA in FIG. 6A, and FIG. 7B shows light reception by the image sensor 22 of the pupil monitor system 23 in FIG. 6A. The part 22a is shown. In FIG. 7A, the reflecting surfaces of the mirror elements 16A, 16B, and 16 of the SLM 14 are a flat surface, a concave surface, and a convex surface, respectively. In the present embodiment, when measuring the deflection amount of the reflecting surface of each mirror element 16 of the SLM 14, the illumination control unit 36 in FIG. 6A first controls the beam expander 11 to control the mirror element 16 of the SLM 14. By irradiating the array with illumination light IL composed of parallel light beams, the determination unit 34 obtains the size d of the beam spot formed on the light receiving unit 22a of the image sensor 22. In this state, as shown in FIG. 3B, the reflected light beam spot BSA1 from the flat mirror element 16A is minimized, and the reflected light beam spots BSB1 and BSC1 from the concave and convex mirror elements 16B and 16C. Becomes larger.

  Thereafter, the illumination control unit 36 in FIG. 6A shifts the second lens 11b of the beam expander 11 to the position A1, and the divergent light 62 is applied to the array of mirror elements 16 in the SLM 14 (see FIG. 7A). Irradiation light IL consisting of is irradiated. Then, the determination unit 34 uses the lights ILA1, ILB1, and ILC1 branched from the reflected lights ILA, ILB, and ILC from the mirror elements 16A, 16B, and 16C of FIG. The size d of the beam spots BSA2, BSB2 and BSC2 formed on the light receiving portion 22a is obtained. In this state, the reflected light ILB from the concave mirror element 16B becomes a substantially parallel light beam, the reflected light ILA from the flat mirror element 16A becomes a divergent light beam, and the reflected light ILC from the convex mirror element 16C becomes more divergent. Therefore, the beam spot BSB2 becomes the smallest, the beam spot BSB2 becomes slightly larger, and the beam spot BSC2 becomes the largest. Then, the determination unit 34 can detect that the reflection surface of the mirror element 16B corresponding to the smallest beam spot BSB2 is concave and that the reflection surface of the mirror element 16C corresponding to the largest beam spot BSC2 is convex. As described above, the amount of deflection of the reflecting surface of each mirror element 16 of the SLM 14 and the detection result indicating whether the deflection is concave or convex are supplied to the illumination control unit 36.

  As an example, when all the mirror elements 16 of the SLM 14 are bent in a concave shape, and when the amount of bending of the mirror elements 16 exceeds a reference amount as in the first embodiment (a parallel light beam is incident). In the state, the beam spot size d exceeds the reference value ds). At this time, the illumination control unit 36 illuminates the diverging light 62 on the entire surface of the array of mirror elements 16 of the SLM 14 via the beam expander 11 so as to cancel out the average deflection amount of all the mirror elements 16. Irradiate with IL. As a result, the reflected light from each mirror element 16 becomes a substantially parallel light beam, and the reflected light forms a substantially smallest beam spot on the illumination pupil plane IPP (incident surface 25AI), so that the illumination conditions can be set with high accuracy.

  Similarly, as shown in FIG. 7C, when all of the mirror elements 16 of the SLM 14 are mirror elements 16C that are bent in a convex shape exceeding the reference amount, the illumination control unit 36 includes a beam expander. 11 irradiates the entire surface of the array of mirror elements 16 of the SLM 14 with illumination light IL composed of convergent light 63. Thereby, the reflected light from each mirror element 16C becomes a substantially parallel light beam, and the illumination conditions can be set with high accuracy.

  As described above, the exposure apparatus EXA of the present embodiment includes the illumination apparatus 8A including the SLM (spatial light modulator) 14, and the illumination apparatus 8A includes the illumination optical system ILSA, the illumination control unit 36, the pupil monitor system 23, and the determination. A detection unit including the unit 34. Then, the detection unit detects the size of the beam spot of the reflected light formed on the light receiving unit 22a of the image sensor 22 (physical quantity related to the surface shape of the reflection surface), and from this detection result, each mirror element of the SLM 14 It is determined whether the deflection of the sixteen reflecting surfaces is convex or concave and whether the amount of deflection is larger than the reference amount (detection step). And the illumination control part 36 is based on the bending state (convex or concave) of the mirror element 16 calculated | required from the physical quantity relevant to the surface shape of the mirror element 16 detected by the detection part, and the bending amount. The degree of parallelism of the illumination light IL incident on the array is adjusted so that the reflected light guided from the plurality of mirror elements 16 to the illumination pupil plane IPP (irradiated surface) forms a small beam spot ( Adjustment process).

According to the present embodiment, the mirror element is adjusted by adjusting the parallelism of the illumination light IL incident on the plurality of mirror elements 16 in accordance with the shape of the reflection surface (reflection surface shape) of the plurality of mirror elements 16 of the SLM 14. Even when the shape of the sixteen reflecting surfaces (surface shape or properties such as deflection) changes, a distribution close to the target light intensity distribution is obtained on the illumination pupil plane IPP.
Further, in the present embodiment, it is possible to determine whether the deflection of the mirror element 16 is convex or concave, and the parallelism of the illumination light IL incident on the plurality of mirror elements 16 is adjusted according to the state. Therefore, the reflected light from the mirror element 16 in which the bending has occurred can be continuously used.

In the present embodiment, the following modifications are possible.
First, also in the present embodiment, the reflected light from the mirror element 16 in which the deflection has occurred may be guided to a region inside the partial pupil region of the illumination pupil plane IPP.
For example, as shown in FIG. 6B, when the illumination light IL made of the divergent light 62 is incident on the array of mirror elements 16 of the SLM 14, different positions P1, P2,. If the reflecting surface of the mirror element 16 at an integer is set in a state parallel to the arrangement surface RP, the mirror elements 16 at the positions P1 to PI do not have the reflected light parallel to the optical axis AXI. Arise. In this case, if the state in which the reflected light from each mirror element 16 is parallel to the optical axis AXI is the neutral position of each mirror element 16, the reflected light from each mirror element 16 on the optical axis AXI with respect to the diverging light 62 A state where the angle of each mirror element 16 is adjusted so as to be parallel and the angle after the adjustment is set may be set as the neutral position. Thereafter, by controlling the angle of each mirror element 16 with the neutral position as a reference, the light intensity distribution on the illumination pupil plane IPP can be controlled in the same manner as when the parallel luminous flux is incident on the SLM 14. The same applies when the convergent light is incident on the SLM 14.

  In addition, as indicated by a two-dot chain line in FIG. 6A, a diffractive optical element comprising a plurality of diffractive optical elements (Diffractive Optical Elements) is formed in the optical path of the illumination light IL between the mirror 13 and the SLM 14 by the drive unit DRV2. The member 60 may be insertable / removable. As shown in FIG. 6C, the diffractive optical member 60 includes a first diffractive optical element 60B that makes incident parallel light a plurality of diverging lights 62A to 62B, and a plurality of convergent lights 63A to 63B. And the second diffractive optical element 60C. In this modification, the array of mirror elements 16 of the SLM 14 is divided into, for example, two groups, and it is determined for each group whether the average amount of deflection of the mirror elements 16 therein is concave or convex.

  In this modification, the mirror elements 16 in the first group (second array region 52B) are mirror elements 16B bent in a concave shape, and the mirror elements 16 in the second group (third array region 52C) are convex. In the case of the mirror element 16C bent in the direction, the diverging light 62B or the like is incident on the mirror element 16B in the second array region 52B via the first diffractive optical element 60B, and the mirror element 16C in the third array region 52C. The convergent light 62B or the like is incident through the second diffractive optical element 60C. As a result, even when the convex mirror element 16C and the concave mirror element 16B are mixed in the array of the SLM 14, the reflected light from each mirror element 16 as a whole becomes a substantially parallel light flux, thereby improving the illumination condition. Can be set to accuracy.

In the above embodiment, the surface shape (convex or concave) of the reflecting surface is detected as the physical quantity related to the surface shape of the reflecting surface of the mirror element 16 of the SLM 14. At least one of the curvature of the surface (degree of convex or concave), the position in the normal direction with respect to the arrangement surface of the reflecting surface, the inclination angle of the reflecting surface, and the reflectance may be detected.
Instead of the diffractive optical member 60, it is also possible to use a microlens array member in which a microlens array made of a convex lens and a microlens array made of a concave lens are combined.

  In the above embodiment, the light from the mirror element 16 in which the variation in driving characteristics occurs is guided to the inner region 55Ab formed on the illumination pupil plane IPP, and the mirror element in which the variation in driving characteristics does not occur. The light from 16 may be guided to a peripheral region 55Aa formed on the illumination pupil plane IPP. At this time, the region where the mirror element in which the variation in driving characteristics is generated can be regarded as the second array region, and the region in which the mirror element in which the variation in driving characteristic is not generated is arranged in the first array. It can be regarded as an area. Here, the drive characteristics of the mirror element 16 are the control voltage (control amount) applied to the electrode of the mirror element 16 of the SLM 14 and the angle (drive amount) of the mirror element 16 set according to this. Point to relationship.

Further, in the above-described embodiment, the variation in the drive characteristics (for example, the tilt angle (tilt angle) / control voltage) of the mirror elements 16 arranged in the first array region is the mirror element 16 arranged in the second array region. The drive characteristics (for example, tilt angle (tilt angle) / control voltage) are not limited to a state where there is no variation at all.
In each of the above embodiments, in order to set the light intensity distribution (light quantity distribution) on the entrance planes 25I and 26AI or the illumination pupil plane IPP, the tilt angles around two orthogonal axes of the plurality of mirror elements 16 can be controlled. SLM 14 is used. However, the illumination method of the above embodiment can also be applied when using a spatial light modulator having an array of a plurality of mirror elements each capable of controlling the position of the reflecting surface in the normal direction instead of the SLM 14. is there. As such a spatial light modulator, for example, the spatial light modulator disclosed in FIG. 1d of US Pat. No. 5,312,513 and US Pat. No. 6,885,493 may be used. it can. In these spatial light modulators, by forming a two-dimensional height distribution, an action similar to that of the diffractive surface can be given to incident light. Note that the spatial light modulator having a plurality of two-dimensionally arranged reflection surfaces described above is disclosed in accordance with, for example, US Pat. No. 6,891,655 and US Patent Publication No. 2005/0095749. It may be deformed. Further, in place of the SLM 14, for example, when using an arbitrary optical modulator including a plurality of optical elements capable of controlling the state of incident light (reflection angle, refraction angle, transmittance, etc.), Applicable.

Further, in the above-described embodiment, the fly-eye lens 25 that is the wavefront division type integrator of FIG. 1 is used as an optical integrator. However, as the optical integrator, a rod type integrator as an internal reflection type optical integrator can be used.
In addition, the illumination devices 8 and 8A and the illumination method of the above embodiment are formed on the wafer W by forming interference fringes on the wafer W as disclosed in, for example, International Publication No. 2001/035168 pamphlet. The present invention can be applied to an exposure apparatus (lithography system) that forms an and space pattern.

In the above-described embodiment, the present invention is applied to the illumination optical system that illuminates the mask (or wafer) in the exposure apparatus. However, the present invention is not limited to this, and the object other than the mask (or wafer) is used. The present invention can also be applied to a general illumination optical system that illuminates an illumination object.
Further, when an electronic device (microdevice) such as a semiconductor device is manufactured by using the exposure apparatus EX, EXA or the exposure method of the above embodiment, the electronic device has a function / performance of the device as shown in FIG. Step 221 for performing design, Step 222 for manufacturing a mask (reticle) based on this design step, Step 223 for manufacturing a substrate (wafer) as a base material of the device, and a mask by the exposure apparatus or exposure method of the above-described embodiment. The process of exposing the pattern to the substrate, the process of developing the exposed substrate, the substrate processing step 224 including the heating (curing) and etching process of the developed substrate, the device assembly step (dicing process, bonding process, packaging process, etc.) (Including machining process) 225, inspection step 226, etc. It is produced through.

  In other words, the device manufacturing method uses the exposure apparatus or the exposure method according to the above-described embodiment to expose a substrate (wafer W) through a mask pattern and to process the exposed substrate. Step (ie, developing the resist on the substrate and forming a mask layer corresponding to the mask pattern on the surface of the substrate, and processing the surface of the substrate via the mask layer (heating, etching, etc.) Processing step).

According to this device manufacturing method, an image of a reticle pattern can always be exposed on a wafer with high accuracy, and thus an electronic device can be manufactured with high accuracy.
The present invention can also be applied to an immersion type exposure apparatus disclosed in, for example, US Patent Application Publication No. 2007/242247 or European Patent Application Publication No. 1420298. Furthermore, the present invention can be applied to an illumination optical apparatus that does not use a condenser optical system. Further, the present invention can also be applied to a proximity type exposure apparatus that does not use a projection optical system.

  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.

  As described above, the present invention is not limited to the above-described embodiment, and various configurations can be taken without departing from the gist of the present invention.

  EX ... exposure device, ILS ... illumination optical system, R ... reticle, PL ... projection optical system, W ... wafer, IPP ... illumination pupil plane, 8 ... illumination device, 10 ... light source, 14 ... spatial light modulator (SLM), DESCRIPTION OF SYMBOLS 16 ... Mirror element, 17 ... SLM control system, 23 ... Pupil monitor system, 25 ... Fly eye lens, 35 ... Main control system, 36 ... Illumination control part, 39 ... Aperture measurement system

Claims (35)

In an illumination method for guiding light from a light source to an irradiated surface through a plurality of reflective elements included in the spatial light modulator,
The light from the reflective element having the first reflective surface shape that is arranged in the first area among the arrangement areas in which the plurality of reflective elements are arranged is guided to the second area formed on the irradiated surface. When,
The second light is formed on the irradiated surface with light from a reflective element that is disposed in a third region different from the first region and has a second reflective surface shape different from the first reflective surface shape. Leading to a fourth region different from the region;
The lighting method characterized by including. The second region where the light from the reflective element having the first reflective surface shape is guided is set at a peripheral portion of the irradiated region formed on the irradiated surface,
2. The fourth region to which light from a reflective element having the second reflective surface shape is guided is set at a central portion of an irradiated region formed on the irradiated surface. The illumination method described.   The light from the reflective element having the second reflective surface shape is lighter than the first incident region formed in the second region by the light from the reflective element having the first reflective surface shape. The illumination method according to claim 1, wherein a size of the second incident region formed on the surface is larger.   4. The illumination method according to claim 1, wherein light from the plurality of reflecting elements is guided to a plurality of irradiated regions of the irradiated surface. 5. The light from the light source is guided to the object to be illuminated through the illumination optical system,
The illumination method according to claim 1, wherein the irradiated surface is a pupil plane of the illumination optical system or a plane equivalent to the pupil plane.   The illumination method according to claim 1, further comprising guiding light from the plurality of reflection elements to the irradiated surface via an optical Fourier transform optical system. Detecting a physical quantity related to a surface shape of a reflecting surface of the plurality of reflecting elements;
Adjusting light guided from the plurality of reflective elements to the illuminated surface based on a physical quantity related to the detected surface shape of the reflective surface;
The illumination method according to any one of claims 1 to 6, further comprising: In an illumination method for guiding light from a light source to an irradiated surface through a plurality of reflective elements included in the spatial light modulator,
Detecting a physical quantity related to a surface shape of a reflecting surface of the plurality of reflecting elements;
Adjusting light guided from the plurality of reflective elements to the illuminated surface based on a physical quantity related to the detected surface shape of the reflective surface;
The lighting method characterized by including. Adjusting the light guided to the irradiated surface is
The illumination method according to claim 7, further comprising changing an irradiation position of the light from the plurality of reflection elements on the irradiated surface. Adjusting the light guided to the irradiated surface is
10. The illumination method according to claim 7, comprising adjusting at least one of positions and postures of the plurality of reflection elements included in the spatial light modulator. 11. Detecting a physical quantity related to the surface shape of the reflecting surface of the plurality of reflecting elements,
11. The illumination method according to claim 7, further comprising detecting a light intensity distribution of an irradiated area of the irradiated surface to which light from the plurality of reflecting elements is guided. Detecting a physical quantity related to the surface shape of the reflecting surface of the plurality of reflecting elements,
12. The method according to claim 7, further comprising detecting at least one of a surface shape, a curvature, a position, an inclination angle, and a reflectance of the reflecting surfaces of the plurality of reflecting elements. Lighting method. Detecting a physical quantity related to the surface shape of the reflecting surface of the plurality of reflecting elements,
13. The method according to claim 7, further comprising detecting, for each of a plurality of groups including the plurality of reflective elements, a state of deflection of an average reflective surface of the reflective element belonging to each group. The illumination method described in 1. Adjusting the light guided to the irradiated surface is
The illumination according to any one of claims 7 to 13, wherein parallelism of light from the light source incident on a reflective element having the second surface shape among the plurality of reflective elements is controlled. Method.   Among the plurality of reflective elements, the light from the light source that is incident on the reflective element having a concave deflection on the reflective surface is diverged, and the light is incident on the reflective element on which the convex deflection is generated. The illumination method according to claim 1, further comprising controlling parallelism of light from the light source so as to converge light from the light source.   The plurality of reflecting elements have a reflecting surface that reflects incident light, and at least one of a position in a normal direction and an inclination angle of the reflecting surface is variable. The illumination method according to claim 1. In an exposure method in which a pattern is illuminated with light from an exposure light source, and the substrate is exposed with light from the exposure light source via the pattern and a projection optical system,
An exposure method for illuminating the pattern with light from the exposure light source using the illumination method according to claim 1. In a lighting device that includes a spatial light modulator having a plurality of reflective elements and guides light from a light source to an irradiated surface,
While guiding the light from the reflective element having the first reflective surface shape arranged in the first region among the arranged regions where the plurality of reflective elements are arranged, to the second region formed on the irradiated surface ,
The second light is formed on the irradiated surface with light from a reflective element that is disposed in a third region different from the first region and has a second reflective surface shape different from the first reflective surface shape. An illumination device comprising: a control device that controls the plurality of reflective elements so as to lead to a fourth region different from the region. The controller is
Setting the second region where the light from the reflective element having the first reflective surface shape is guided to the peripheral portion of the irradiated region formed on the irradiated surface;
19. The fourth region to which light from a reflective element having the second reflective surface shape is guided is set at the center of an irradiated region formed on the irradiated surface. Lighting equipment.   The light from the reflective element having the second reflective surface shape is lighter than the first incident region formed in the second region by the light from the reflective element having the first reflective surface shape. The lighting device according to claim 18 or 19, wherein a size of the second incident region formed on the light emitting device is larger. The controller is
21. The lighting device according to claim 18, wherein light from the plurality of reflecting elements is guided to a plurality of irradiated regions of the irradiated surface. An illumination optical system that guides light from the light source to an object to be illuminated;
The illumination apparatus according to any one of claims 18 to 21, wherein the irradiated surface is a pupil plane of the illumination optical system or a plane equivalent to the pupil plane.   The illuminating device according to any one of claims 18 to 22, further comprising an optical Fourier transform optical system that guides light from the plurality of reflecting elements to the irradiated surface. A detection device that detects a physical quantity related to a surface shape of a reflection surface of the plurality of reflection elements;
The said control apparatus adjusts the light guide | induced to the said to-be-irradiated surface from these reflective elements based on the detection result of the said detection apparatus, The Claim 1 characterized by the above-mentioned. Lighting device.   The lighting device according to claim 24, wherein the control device changes an irradiation position of the light from the plurality of reflecting elements on the irradiated surface in order to adjust light guided to the irradiated surface. .   The control device adjusts at least one of positions and postures of the plurality of reflecting elements included in the spatial light modulator in order to adjust light guided to the irradiated surface. The lighting device according to 25.   27. The image sensor according to any one of claims 24 to 26, wherein the detection device includes an image sensor that detects a light intensity distribution of an irradiated region of the irradiated surface to which light from the plurality of reflecting elements is guided. The lighting device described in 1.   28. The detection device according to claim 24, wherein the detection device detects at least one of a surface shape, a curvature, a position, an inclination angle, and a reflectance of a reflecting surface of the plurality of reflecting elements. The lighting device described in 1.   The detection device detects, for each of a plurality of groups including the plurality of reflection elements, a deflection state of an average reflection surface of the reflection elements belonging to each group. The lighting device according to one item.   A first optical member that controls parallelism of light from the light source that is incident on a reflective element having the second surface shape among the plurality of reflective elements in order to adjust light guided to the irradiated surface; 30. The illumination device according to any one of claims 18 to 29, comprising:   Among the plurality of reflective elements, the light from the light source that is incident on the reflective element having a concave deflection on the reflective surface is diverged, and the light is incident on the reflective element on which the convex deflection is generated. The illumination device according to any one of claims 18 to 30, further comprising a second optical member that controls parallelism of light from the light source so as to converge light from the light source.   32. The reflective element according to claim 18, wherein the reflective element has a reflective surface that reflects incident light, and at least one of a position in a normal direction and an inclination angle of the reflective surface is variable. The lighting device described in 1. In an exposure apparatus that illuminates a pattern with light from an exposure light source and exposes the substrate with light from the exposure light source through the pattern and a projection optical system,
A lighting device according to any one of claims 18 to 32 is provided,
An exposure apparatus that illuminates the pattern with light from the exposure light source using the illumination apparatus. Forming a pattern of a photosensitive layer on a substrate using the exposure method according to claim 17;
Processing the substrate on which the pattern is formed;
A device manufacturing method including: Forming a pattern of a photosensitive layer on a substrate using the exposure apparatus according to claim 33;
Processing the substrate on which the pattern is formed;
A device manufacturing method including:

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