Measuring apparatus, exposure apparatus, and device manufacturing method

Abstract

To provide a measurement device capable of highly accurately measuring an operational state of a spatial light modulator in a short time between exposures using the spatial light modulator in order to perform high-accuracy exposure.SOLUTION: A measurement device comprises: an illumination system which is included in a spatial light modulator, and irradiates an array surface, on which each reflection surface of a plurality of spatial light modulation elements each having a reflection surface is arrayed, with light; a detection optical system which forms an image of the array surface on the basis of light from the plurality of reflection surfaces; an imaging part which detects the image of the array surface formed by the detection optical system; and a calculation part which calculates positional information of the spatial light modulation elements on the basis of detected light quantity being light quantity of the image detected by the imaging part, where the positional information of the spatial light modulation element is positional information of the reflection surface of the spatial light modulation element in a normal direction of the array surface or positional information regarding a rotation angle of the reflection surface of the spatial light modulation elements from the array surface.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a measuring device , dew an optical device, and a device manufacturing method.

Background Art

[0002] As a member for forming a pattern to be exposed and transferred, an exposure apparatus using a spatial light modulator such as a digital micromirror device whose reflectivity in a predetermined direction of irradiation light is variable has been proposed (Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

[0004] According to a first aspect, a measuring device includes an illumination system that irradiates light onto an array surface on which reflection surfaces of a plurality of spatial light modulation elements each having a reflection surface included in a spatial light modulator are arranged, a detection optical system that forms an image of the array surface based on light from the plurality of reflection surfaces, an imaging unit that detects the image of the array surface formed by the detection optical system, and an arithmetic unit that calculates position information of the spatial light modulation elements based on a detected light amount of the image detected by the imaging unit, wherein the position information of the spatial light modulation elements is position information of the reflection surfaces of the spatial light modulation elements in a normal direction of the array surface In the report Yes, the imaging unit includes a plurality of pixels including a first pixel, and detects the light amount of the image formed by a plurality of first spatial light modulation elements each having the reflection surface included in the spatial light modulator by the first pixel, and the arithmetic unit calculates the position information of the first spatial light modulation elements based on the light amount detected by the first pixel, and the position information of the first spatial light modulation elements is position information of the reflection surfaces of the first spatial light modulation elements in a normal direction of the array surface In the report Yes the law of nature 、 The calculation unit has a storage unit that stores the correspondence between the light intensity of the image and the position information of the spatial light modulation element, and calculates the position information of the spatial light modulation element from the detected light intensity of the image based on the correspondence stored in the storage unit, and the correspondence is a correspondence based on the wavelength of the light. According to the second embodiment, the measuring device includes an illumination system that irradiates light onto an array surface in which the reflective surfaces of a plurality of spatial light modulators, each having a reflective surface, are arranged, a detection optical system that forms an image of the array surface based on the light from the plurality of reflective surfaces, an imaging unit that detects the image of the array surface formed by the detection optical system, and a calculation unit that calculates position information of the spatial light modulators based on the detected light amount, which is the amount of light in the image detected by the imaging unit, wherein the position information of the spatial light modulators is the position information of the reflective surface of the spatial light modulator in the direction normal to the array surface, and the imaging unit includes a plurality of pixels including a first pixel. The first pixel detects the amount of light in the image formed by a plurality of first spatial light modulation elements, each having a reflective surface and included in the spatial light modulator, which include a number of pixels. The calculation unit calculates position information of the first spatial light modulation elements based on the amount of light detected by the first pixel. The position information of the first spatial light modulation elements is the position information of the reflective surface of the first spatial light modulation elements in the direction normal to the array surface. For the spatial light modulator used for light of a first wavelength λ1, the detection optical system detects the image using light of a second wavelength λ2, which has a wavelength of 1.5 times or more and 3.3 times or less than or equal to the first wavelength λ1. According to a third embodiment, the measuring device comprises: an illumination system that irradiates light onto an array surface in which the reflective surfaces of a plurality of spatial light modulators, each having a reflective surface, are arranged; a detection optical system that forms an image of the array surface based on the light from the plurality of reflective surfaces; an imaging unit that detects the image of the array surface formed by the detection optical system; and a calculation unit that calculates position information of the spatial light modulators based on the detected light quantity, which is the amount of light in the image detected by the imaging unit, wherein the position information of the spatial light modulators is the position information of the reflective surfaces of the spatial light modulators in the direction normal to the array surface. The imaging unit includes a plurality of pixels, including a first pixel, and the amount of light in the image formed by a plurality of first spatial light modulation elements, each having a reflective surface, included in the spatial light modulator, is detected by the first pixel. The calculation unit calculates position information of the first spatial light modulation elements based on the amount of light detected by the first pixel. The position information of the first spatial light modulation elements is the position information of the reflective surface of the first spatial light modulation elements in the direction normal to the array surface. The detection optical system includes an aperture that allows specularly reflected light from the reflective surface to pass through and blocks +1st-order diffracted light and -1st-order diffracted light. The 4 According to this embodiment, the exposure apparatus comprises an illumination optical system for illuminating a spatial light modulator having a plurality of spatial light modulation elements having reflective surfaces arranged on an array plane, a projection optical system for projecting light from the spatial light modulator onto a substrate to be exposed, and the measuring apparatus described above. The 5 According to this embodiment, the device manufacturing method includes forming a resist on the surface of a substrate, exposing the resist to an exposure pattern using the exposure apparatus described above, and forming a circuit pattern based on the exposure pattern. [Brief explanation of the drawing]

[0005] [Figure 1] A diagram schematically showing the configuration of the measuring device according to the first embodiment. [Figure 2] A schematic diagram showing the configuration of a spatial light modulator. [Figure 3] This diagram shows an example of the relationship between the specified position transmitted to the spatial light modulation element and the actual set position where the spatial light modulation element is configured. [Figure 4] A diagram illustrating the principle of modulation of the light intensity of specularly reflected light by a spatial light modulator. [Figure 5] This figure shows an example of the relationship between the amount of specularly reflected light from a spatial light modulator and the difference in height of the reflective surfaces between two groups of spatial light modulators arranged alternately within the modulator. [Figure 6] A diagram illustrating the principle of modulation of specularly reflected light intensity by a spatial light modulator with a different configuration. [Figure 7] A diagram schematically showing the configuration of the measuring device according to the second embodiment. [Figure 8] A diagram schematically showing the configuration of the exposure apparatus of the fourth embodiment. [Figure 9] A diagram illustrating the device manufacturing method of the fifth embodiment. [Modes for carrying out the invention]

[0006] (Measuring device of the first embodiment) Figure 1 is a schematic diagram showing the configuration of the measuring device 1 of the first embodiment. The measuring device 1 of the first embodiment is a device for measuring the operating state of the spatial light modulator 20 and includes a detection unit 5 enclosed by a dashed line in Figure 1.

[0007] In Figure 1 and the figures referenced below, the X, Y, and Z directions indicated by arrows are orthogonal to each other, and each of the X, Y, and Z directions represents the same direction in each figure. Hereafter, the directions indicated by each arrow will be referred to as the +X direction, +Y direction, and +Z direction, respectively. The position in the X direction will be called the X position, the position in the Y direction will be called the Y position, and the position in the Z direction will be called the Z position.

[0008] The spatial light modulator 20 is held by a holding part 28, which is movable in the X and Y directions on a guide part 29. Therefore, the spatial light modulator 20 is held so as to be movable relative to the detection part 5 in the X and Y directions. The holding part 28 and the guide part 29 together or individually are also referred to as the moving mechanism 27.

[0009] Figure 2 is a schematic diagram showing the configuration of the spatial light modulator 20, which is the target of measurement by the measuring device 1. Figure 2(a) shows the spatial light modulator 20 as viewed from the -Z direction, and Figure 2(b) shows the XZ cross-section of the spatial light modulator 20 at the AA cutting line in Figure 2(a).

[0010] On the -Z side of the spatial light modulator 20, a plurality of spatial light modulation elements 22 are arranged, each having a reflective surface 22R at its -Z end. The plurality of spatial light modulation elements 22 are arranged such that each reflective surface 22R roughly coincides with an array plane DP, which is a single XY plane near the -Z end of the spatial light modulator 20. As an example, the plurality of spatial light modulation elements 22 are arranged along the X and Y directions, with the period of the arrangement of spatial light modulation elements 22 in the X direction being PX and the period of the arrangement in the Y direction being PY.

[0011] Each of the spatial light modulation elements 22 is held by the housing 21 of the spatial light modulator 20 via a holding member (not shown) having elasticity. Opposing electrodes 23 are respectively disposed at portions of the housing 21 that face the +Z side of each of the spatial light modulation elements 22. When a predetermined voltage is applied as a control signal Sa from the modulation control unit 24 to each of the opposing electrodes 23, each of the spatial light modulation elements 22 moves parallel in the Z direction and is set at a Z position corresponding to the voltage of the control signal Sa applied to the opposing electrode 23 facing it. The modulation control unit 24 sends the control signal Sa to each of the opposing electrodes 23 based on the control signal S1 supplied from the outside.

[0012] As described above, since the array plane DP is one of the XY planes, the Z direction is the normal direction with respect to the array plane DP. The first region A1 and the second region A2 shown by the dashed line in Fig. 2(a) will be described later.

[0013] Fig. 3 is a diagram showing an example of a position setting relationship FR which is the relationship between the specified position (horizontal axis), which is the Z position of the reflection surface 22R specified by the control signal S1 and the control signal Sa, and the actual set position (vertical axis), which is the Z position where the reflection surface 22R is actually set. The actual set position is the relative position in the Z direction from the array plane DP. If the actual set position is 0 [nm], it is assumed that the reflection surface 22R coincides with the array plane DP.

[0014] The position setting relationship FR deviates from the ideal proportional relationship FI due to manufacturing errors, thermal expansion, and charging, etc. of each member constituting the spatial light modulator 20. Even in one spatial light modulator 20, the position setting relationship FR may be different for the spatial light modulation elements 22 having different positions within the array plane DP.

[0015] Referring to Fig. 1, the configuration of the detection unit 5 of the measuring device 1 will be described. The detection unit 5 includes a detection light source 11, a light transmitting lens 12, an illumination aperture stop 13, a branching element 14, an objective lens 15, a detection aperture stop 16, an imaging lens 17, an imaging unit 18, and a control unit 25.

[0016] Of these, the light-transmitting lens 12, illumination aperture diaphragm 13, branching element 14, and objective lens 15 constitute an illumination system that irradiates light onto the array plane DP of the spatial light modulation elements 22 that make up the spatial light modulator 20. Furthermore, the objective lens 15, branching element 14, detection aperture diaphragm 16, and imaging lens 17 included in the area enclosed by the dashed line constitute a detection optical system 10 that forms an image of the array plane DP on the imaging surface 19 of the imaging unit 18, such as a solid-state image sensor.

[0017] The illumination light ILa emitted from the detection light source 11 is made nearly parallel by the light transmission lens 12, and its diameter is restricted by the illumination aperture diaphragm 13 to become illumination light ILb. The illumination light ILb is then incident on a branching element 14 such as a beam splitter, reflected by the branching surface 14s of the branching element 14, and then focused by the objective lens 15. The resulting illumination beam, having an numerical aperture (illumination NA) corresponding to the aperture diameter of the illumination aperture diaphragm 13, is then irradiated onto the array surface DP of the spatial light modulator 20.

[0018] The illumination light ILb is reflected by multiple reflective surfaces 22R (see Figure 2) located near the array plane DP, and a portion of it becomes detection light DLa and enters the objective lens 15. The detection light DLa then enters the branching element 14, passes through the branching surface 14s of the branching element 14, and its diameter is restricted by the detection aperture diaphragm 16 to become detection light DLb.

[0019] The detected light DLb is focused by the imaging lens 17 and incident on the imaging surface 19 of the imaging unit 18, forming an image of the array plane DP on the imaging surface 19. The image of the array plane DP is detected by the imaging unit 18, that is, it is photoelectrically converted into an electrical signal and transmitted to the control unit 25 as an image signal S2. The amount of light in each part of the image of the array plane DP detected by the imaging pixels constituting the imaging unit 18 will also be referred to as the "detected light amount" below.

[0020] The detection light source 11 may be a semiconductor laser, for example, or an LED with a relatively narrow emission wavelength range. The light transmitting lens 12, the objective lens 15, and the imaging lens 17 are not limited to the number of lenses shown (2), but may include any number of lenses, and may all include a reflective optical system. The branching element 14 is not limited to the beam splitter described above, but may be a half-mirror made of a flat glass plate or the like.

[0021] The control unit 25 sends a control signal S1 to the spatial light modulator 20 and controls each spatial light modulation element 22 of the spatial light modulator 20 to be set to a predetermined Z position during measurement. The control unit 25 calculates the position information of the spatial light modulator 20 based on the image signal S2. Therefore, the control unit 25 can also be called a calculation unit.

[0022] The principle of measurement of the spatial light modulator 20 based on the image signal S2 will be explained below with reference to Figures 4 and 5. Figure 4 is a schematic diagram illustrating the principle of modulation of the light intensity of specularly reflected light DLa0 by the spatial light modulator 20. Figures 4(a) and 4(b) are views from the -Z direction of examples of the operating states of the multiple spatial light modulation elements 22 arranged in the first region A1 of the spatial light modulator 20 shown in Figure 2(a). Note that the first region A1 may be any region on the array plane DP of the spatial light modulator 20. Also, the number of spatial light modulation elements 22 included in the first region A1 is not limited to the 4×4 shown in Figures 2 and 4, but may be any other number.

[0023] Figure 4(c) is a cross-sectional view of the spatial light modulator 22 in the first region A1 in the operating state shown in Figure 4(b) and the objective lens 15 shown in Figure 1, viewed from the +Y direction. In Figure 4(c), the illumination light ILb (see Figure 1) irradiated onto the spatial light modulator 20 from the -Z direction is omitted to avoid complexity in the drawing.

[0024] In Figures 4(a) to 4(c), among the spatial light modulation elements 22, those elements whose reflective surface 22R is positioned to roughly coincide with the array plane DP are called the first group of spatial light modulation elements 22a. Among the spatial light modulation elements 22, those elements whose reflective surface 22R is positioned away from the array plane DP in the +Z direction are called the second group of spatial light modulation elements 22b.

[0025] The reflective surface 22R of the first group of spatial light modulation elements 22a is denoted as 22Ra, and the reflective surface 22R of the second group of spatial light modulation elements 22b is denoted as 22Rb. Furthermore, the first group of spatial light modulation elements 22a is distinguished by a diagonal line extending from the upper left to the lower right, and the second group of spatial light modulation elements 22b is distinguished by a diagonal line extending from the lower left to the upper right.

[0026] The reflective surface 22Ra of the first group of spatial light modulation elements 22a is set to a designated position of 0 (on the array plane DP) by the control signal S1 from the control unit 25 and the control signal Sa from the modulation control unit 24. The reflective surface 22Rb of the other group of spatial light modulation elements 22b is set to a designated position at a position where it is located at a distance of a specified position difference H1d in the +Z direction from the array plane DP by the control signal S1 from the control unit 25 and the control signal Sa from the modulation control unit 24.

[0027] Furthermore, while the actual set values ​​of the reflective surface 22Ra of the first group of spatial light modulation elements 22a and the reflective surface 22Rb of the second group of spatial light modulation elements 22b are close to their respective specified positions, as mentioned above, they do not necessarily coincide. The difference between the actual set Z positions of the reflective surface 22Ra of the first group of spatial light modulation elements 22a and the reflective surface 22Rb of the second group of spatial light modulation elements 22b is called the position difference H1. The position difference H1 does not necessarily coincide with the specified position difference H1d mentioned above. In Figure 3(c), the position difference H1 and the specified position difference H1d mentioned above represent the same portion in terms of length, as the difference in length is negligible compared to the scale of the drawing.

[0028] In Figures 4(a) to 4(c), a plurality of first groups of spatial light modulation elements 22a and a plurality of second groups of spatial light modulation elements 22b, having a relative positional difference H1 in the Z direction, are arranged alternately based on a control signal S1 from the control unit 25. Here, "arranged alternately" means that in a plurality of spatial light modulation elements 22 arranged along a predetermined direction in the XY plane, the first group of spatial light modulation elements 22a and the second group of spatial light modulation elements 22b are arranged alternately.

[0029] Figure 4(a) shows the operating state in which the first group of spatial light modulation elements 22a and the second group of spatial light modulation elements 22b are arranged alternately along two directions, the X direction and the Y direction, in other words, in a checkerboard pattern. Figure 4(b) shows an operating state in which the first group of spatial light modulation elements 22a and the second group of spatial light modulation elements 22b are arranged alternately along the X direction, and either the first group of spatial light modulation elements 22a or the second group of spatial light modulation elements 22b are arranged continuously along the Y direction.

[0030] When illumination light ILb (see Figure 1) is shone onto the reflective surface 22R of each spatial light modulation element 22 from approximately the -Z direction, a phase difference corresponding to the difference in the actual set position, which is the Z position of each reflective surface 22R, i.e., the position difference H1, is added to the reflected light from each reflective surface 22Ra and 22Rb. Then, according to this phase difference, the period PX of the arrangement of the reflective surfaces 22R in the X direction, and the period PY of the arrangement of the reflective surfaces 22R in the Y direction (see Figure 1), the reflected light is separated into specularly reflected light and multiple diffracted light, which will be described later, and each is emitted from the array surface DP with a different emission angle (diffraction angle).

[0031] As described above, Figure 4(c) shows the reflected light from the spatial light modulation element 22 in the first region A1 in the operating state shown in Figure 4(b). Therefore, the reflected light is separated into specular reflection light DLa0 and diffracted light such as the +1st order diffracted light DLap and -1st order diffracted light DLam in the X direction. The specularly reflected light DLa0 is emitted in a direction perpendicular to the array plane DP (-Z direction). The diffraction angles θ of the +1st order diffracted light DLap and the -1st order diffracted light DLam will be described later.

[0032] Figure 4(d) shows the positions of the specular reflected light DLa0, the +1st order diffracted light DLap, and the -1st order diffracted light DLam, etc., at the detection aperture diaphragm 16. The detection aperture diaphragm 16 has an opening 16o with a radius corresponding to the numerical aperture NA2 on the spatial light modulator 20 side of the detection optical system 10, centered at its center 16c, and the area outside the opening 16o is a shielding portion that blocks light. The distances DX and DY shown in Figure 4(d) will be explained later.

[0033] Figure 4(d) also shows the diffracted light generated from the spatial light modulation element 22, in which the first group of spatial light modulation elements 22a and the second group of spatial light modulation elements 22b, which have different Z positions as shown in Figure 4(a), are arranged in a checkerboard pattern. The spatial light modulation element 22 shown in Figure 4(a) generates diffracted light DLapp with (+1, +1) order, diffracted light DLapm with (+1, -1) order, diffracted light DLamp with (-1, +1) order, and diffracted light DLamm with (-1, -1) order, respectively. Specular reflected light DLa0 is also generated.

[0034] However, in any case, the first-order diffracted light (DLap, DLam, DLapp, DLapm, DLamp, DLamm) from the spatial light modulator 20 is blocked by the detection aperture diaphragm 16 and therefore does not reach the imaging unit 18.

[0035] Meanwhile, the specularly reflected light DLa0 from the spatial light modulator 20 passes through the aperture 16o of the detection aperture diaphragm 16, through the imaging lens 17, and reaches the imaging unit 18. Thereupon, an image of the array plane DP is formed on the imaging surface 19 of the imaging unit 18. Consequently, the amount of specularly reflected light DLa0 from each region such as the first region A1 on the array plane DP is detected by each imaging pixel in the imaging unit 18 as the amount of light in the image of each region of the array plane DP.

[0036] When illumination light of a predetermined wavelength is shone on the array surface DP at a predetermined light intensity, the amount (intensity) of the specularly reflected light DLa0 is determined according to the position difference H1, which is the difference in the actual set positions between the first group of spatial light modulation elements 22a and the second group of spatial light modulation elements 22b.

[0037] Figure 5 shows the correspondence between the positional difference H1 (horizontal axis) between the first group of spatial light modulators 22a and the second group of spatial light modulators 22b and the intensity of the specularly reflected light DLa0 from the spatial light modulator 20 (vertical axis), RL1 and RL2. In Figure 5, the horizontal axis scale is in [nm], and the vertical axis scale is set so that the intensity of specularly reflected light DLa0 is 1 when the position difference H1 is 0 [nm].

[0038] The solid line, RL1, shows the correspondence when the wavelength of specularly reflected light DLa0 is 546 nm, as an example, while the dashed line, RL2, shows the correspondence when the wavelength of specularly reflected light DLa0 is 193 nm, as another example. The correspondence RL1 is a relationship that can be roughly expressed by the following equation (1) with respect to the position difference H1, where λ is the wavelength of the specularly reflected light DLa0 (546 [nm]). RL1 = {1+cos(4π×H1 / λ)} / 2 …(1) The correspondence relationship RL2 is the same as that of correspondence relationship RL1.

[0039] The intensity of specularly reflected light DLa0 decreases monotonically with increasing position difference H1 in the range from 0 [nm] to 1 / 4 of each wavelength. Therefore, the position difference H1 between the first group of spatial light modulators 22a and the second group of spatial light modulators 22b within the first group A1 can be calculated based on the correspondence relationship RL1 (RL2) from the intensity of specularly reflected light DLa0, i.e., the amount of detected light in the image of the first region A1, etc.

[0040] The control unit 25 calculates the position difference H1 between the first group of spatial light modulation elements 22a and the second group of spatial light modulation elements 22b within a region such as the first region A1 of the spatial light modulator 20, based on the image signal S2 detected by the imaging unit 18 and the correspondence relationship RL1 (or correspondence relationship RL2) described above. The control unit 25 is equipped with a storage unit 25M, such as a solid memory or magnetic memory, for storing the correspondence relationship RL1. As described above, the position difference H1 corresponds to the position information in the normal direction (Z direction) of the array plane DP of the reflective surface 22R of the spatial light modulation elements 22.

[0041] The detection unit 5, including the control unit 25, may perform the above-described measurement multiple times while varying the value of the specified position difference H1d, and calculate a specified position difference H1d for setting a desired position difference H1 based on the multiple position differences H1 and the specified position difference H1d calculated.

[0042] In order to calculate the position difference H1 with even greater accuracy, the control unit 25 may also calculate the position difference H1 of the spatial light modulator 22 from the detected light amount, based on a reference light amount which is the light amount of the image in the operating state where the position difference H1 is 0 [nm] in a region such as the first region A1 of the spatial light modulator 20.

[0043] In detecting the reference light quantity, the control unit 25 sends a control signal S1 to the spatial light modulator 20 to control each spatial light modulation element 22 so that it is set to the same Z position. Then, similar to the detection of the detected light quantity described above, the light quantity distribution of the image of the array plane DP of the spatial light modulator 20 formed on the imaging surface 19 of the imaging unit 18 is detected as the reference light quantity.

[0044] The control unit 25 may, for example, calculate the position difference H1 of the spatial light modulation element 22 based on the value obtained by dividing the detected light amount in a region such as the first region A1 of the spatial light modulator 20 by the reference light amount described above. This makes it possible to correct detection errors in the detected light amount caused by transmittance unevenness in the illumination system (12~15) or the detection optical system 10.

[0045] To calculate the position difference H1 with even greater accuracy, it is advisable to use the region in the correspondence relationship RL1 and RL2 where the intensity changes significantly in response to the change in position difference H1. This region, for example, corresponds to the region where the intensity value is 0.8 or less and 0.2 or greater.

[0046] For example, if the spatial light modulator 20 being measured is required to have an intensity of 0 for specularly reflected light DLa0 with a wavelength of 193 [nm], the spatial light modulator 20 needs to set the position difference H1 described above to a range of approximately 48 ± 2 [nm], roughly centered at 193 / 4 = 48.25 [nm].

[0047] At this time, when the measuring device 1 detects the image of the first region A1 of the spatial light modulator 20, if light with the same wavelength of 193 [nm] is used, the intensity of the specular reflected light DLa0 with respect to the position difference H1 will be approximately 0, as shown as the correspondence relationship RL2 in Figure 5. For changes near [nm], the intensity of specularly reflected light DLa0 hardly changes. Therefore, light with a wavelength of 193 [nm] is 48 [nm] Not suitable for accurately measuring the positional difference H1 value in the vicinity.

[0048] On the other hand, when using light with a wavelength of 546 [nm] to detect the image of the first region A1 of the spatial light modulator 20 by the measuring device 1, the intensity of the specular reflected light DLa0 at a position difference H1 of 48 [nm] is approximately 0.7, as shown as the correspondence relationship RL2 in Figure 5. Furthermore, the intensity of the specular reflected light DLa0 fluctuates significantly in response to changes in the position difference H1 near 48 [nm].

[0049] Therefore, when measuring the operation of a spatial light modulator 20, which is required to set the intensity of specularly reflected light DLa0 with a wavelength of 193 nm to 0, it is advisable to use 546 nm light as illumination lights ILa and ILb, as an example.

[0050] More generally, when measuring the operation of a spatial light modulator 20, which is required to have an intensity of 0 for specularly reflected light DLa0 at wavelength λ1, it is preferable to use light with a wavelength of λ2, which is 1.5 times or more and 3.3 times or less than or equal to wavelength λ1, as illumination lights ILa and ILb. In this case, at a position difference H1 where the intensity of specularly reflected light DLa0 at wavelength λ1 is 0, the intensity of specularly reflected light DLa0 of light with wavelength λ2 can be in the range of 0.2 to 0.8, and the value of the position difference H1 can be measured with higher precision.

[0051] As mentioned above, in order to measure the position difference H1 with high accuracy, it is best not to allow the first-order diffracted light from the spatial light modulator 20 to enter the detector 18. Therefore, below, we will again refer to Figures 3(a) to 3(d) to explain the numerical aperture NA2 of the detection optical system 10.

[0052] As shown in Figure 4(b), the spatial light modulation element 22 in the first region A1 generates specularly reflected light DLa0 and diffracted light such as the +1st order diffracted light DLap and the -1st order diffracted light DLam in the X direction, as described above. The +1st order diffracted light DLap is emitted from the -Z direction inclined in the +X direction by a diffraction angle θ. Here, the diffraction angle θ is the angle that satisfies the relationship sin(θ) = λ / (2 × PX) when the wavelength of the illumination light ILb is λ. The -1st order diffracted light DLam is emitted from the -Z direction inclined in the -X direction by a diffraction angle θ.

[0053] Furthermore, since the illumination light ILb irradiated onto the array plane DP has a predetermined illumination NA as described above, the specular reflected light DLa0, the +1st order diffracted light DLap, and the -1st order diffracted light DLam are also emitted in directions that spread out within a predetermined angular range centered on the respective directions mentioned above.

[0054] Figure 4(d) shows the positions of the specularly reflected light DLa0, the +1st order diffracted light DLap, and the -1st order diffracted light DLam, etc., at the detection aperture diaphragm 16, as described above. Since the detection aperture diaphragm 16 is located on the pupil plane of the objective lens 15, the positions in the X and Y directions in Figure 4(d) correspond to the sine of the emission angle of the light emitted from the spatial light modulator 20. Specifically, the distance from the center 16c to each point on the detection aperture diaphragm 16 is, for example, the length obtained by multiplying the sine of the emission angle of the light emitted from the spatial light modulator 20 and reaching each point by the focal length of the objective lens 15.

[0055] The center positions of the +1st order diffracted light DLap and the -1st order diffracted light DLam are located at a distance DX from the center 16c in the +X and -X directions, respectively, within the detection aperture diaphragm 16. Here, the distance DX corresponds to the sine of the diffraction angle θ, sin(θ) = λ / (2 × PX), as described above.

[0056] Therefore, if the radius NA2 of the aperture 16o, which is the numerical aperture on the spatial light modulator 20 side of the detection optical system 10, is smaller than λ / (2×PX), the +1st order diffracted light DLap and -1st order diffracted light DLam will be blocked by the detection aperture diaphragm 16 and will not reach the imaging unit 18.

[0057] As shown in Figure 4(d), the center positions of the first-order diffracted light (DLap, DLam, DLapp, DLapm, DLamp, DLamm) are located at distances DX in the ±X direction and DY in the ±Y direction from the center 16c of the detection aperture diaphragm 16, respectively. Here, distance DX corresponds to the distance sin(θ) = λ / (2 × PX) as described above, and distance DY corresponds to the distance sin(θ) = λ / (2 × PY) with respect to the period PY of the arrangement of the reflective surface 22R in the Y direction.

[0058] Therefore, the numerical aperture on the spatial light modulator 20 side of the detection optical system 10 is √[{λ / (2×PX)} 2 +{λ / (2×PX)} 2If the value is smaller than ], the diffracted light (DLapp, DLapm, DLamp, DLamm) is blocked by the detection aperture diaphragm 16 and cannot reach the imaging unit 18.

[0059] When P is the average of the period PX of the X-direction arrangement of the reflective surface 22R and the period PY of the Y-direction arrangement, it is preferable to set the numerical aperture on the spatial light modulator 20 side of the detection optical system 10 to be approximately smaller than √2 × λ ​​ / (2 × P). This allows the diffracted light (DLapp, DLapm, DLamp, DLamm) to be shielded by the detection aperture diaphragm 16, as described above. The period PX of the X-direction arrangement of the reflective surface 22R and the period PY of the Y-direction arrangement may be equal.

[0060] As mentioned above, due to the illumination NA of the illumination light ILb, each diffracted light (DLap, DLam, DLapp, DLapm, DLamp, DLamm) is spread within an angular range of the same magnitude as the illumination NA of the illumination light ILb. Therefore, the numerical aperture (NA2) on the spatial light modulator 20 side of the detection optical system 10, which is the radius NA2 of the aperture 16o, may be set to a value smaller than the values ​​mentioned above minus the illumination NA.

[0061] By the way, if the numerical aperture NA2 on the spatial light modulator 20 side of the detection optical system 10 is too small, the resolution of the detection optical system will decrease, making it difficult to accurately separate and detect the image of the first region A1 of the array plane DP of the spatial light modulator 20 from the image of the region other than the first region A1. Therefore, the numerical aperture NA2 on the spatial light modulator 20 side of the detection optical system 10 should be λ / (5×P) with respect to the wavelength λ of the illumination light ILb and the period P of the arrangement of the spatial light modulator elements 22. It is best to set it to a value larger than the value determined by [the specified parameter].

[0062] Based on the above, the numerical aperture NA2 on the spatial light modulator 20 side of the detection optical system 10 should satisfy the following relationship (2), where P is the period of the arrangement of the spatial light modulation elements 22 and λ is the wavelength of the light detected by the detection optical system 10. λ / (5×P) < NA < √2×λ / (2×P) …(2)

[0063] The wider the field of view of the detection unit 5 in the measuring device 1, the more spatial light modulation elements 22 can be measured in a single detection, thus shortening the measurement time. Therefore, a wider field of view of the detection unit 5 is preferable. However, it is not easy to widen the field of view of the detection unit 5 while maintaining the predetermined resolution necessary for measuring the operating state of the spatial light modulation elements 22, that is, while maintaining the numerical aperture NA2 on the spatial light modulator 20 side of the detection optical system 10 to a predetermined value or higher.

[0064] Therefore, in the measuring device 1 of the first embodiment, the product of the outer diameter D [mm] of the detection field, which is the field of view of the detection unit 5 on the spatial light modulator 20, i.e., the field of view of the detection optical system 10, and the numerical aperture NA2 on the spatial light modulator 20 side of the detection optical system 10 is set to be 0.5 or more, for example.

[0065] Here, the detection field of view is the range on the spatial light modulator 20 in which its image is captured by the imaging surface 19 of the imaging unit 18, and corresponds to a range obtained by reducing (or expanding) the range of the imaging surface 19 by the absolute value of the imaging magnification (lateral magnification) of the detection optical system 10. Furthermore, the outer diameter of the detection field is the maximum length from any one end of the detection field to the other.

[0066] Furthermore, if the detection field of the detection unit 5 is narrower than the array surface DP on which the spatial light modulation elements 22 of the spatial light modulator 20, which is the object of measurement, are arranged, the entire array surface DP may be measured by using the moving mechanism 27 described above. That is, the entire array surface DP may be measured by moving the relative position of the spatial light modulator 20 and the detection optical system 10 using the moving mechanism 27 and performing multiple measurements by the detection unit 5.

[0067] In the above description, the measuring device 1 is assumed to perform measurements on a spatial light modulator 20 having a plurality of spatial light modulation elements 22 that can move in the Z direction. However, the object of measurement for the measuring device 1 may also be an angle-modulated spatial light modulator 20r having a plurality of spatial light modulation elements 22, each of which can rotate within a predetermined angular range, as shown in Figure 6.

[0068] Figure 6 is a cross-sectional view of a part of the angle-modulated spatial light modulator 20r and the objective lens 15 shown in Figure 1, viewed from the +Y direction, and is similar to Figure 4(c) described above. Therefore, the following explanation will also refer to the symbols shown in Figures 1 to 4. In Figure 6, as with Figure 4(c), the illumination light ILb (see Figure 1) irradiated onto the spatial light modulator 20r from the -Z direction is omitted to avoid complexity in the drawing.

[0069] Each of the spatial light modulation elements 22 is held in the housing 21 of the spatial light modulator 20 via an elastic holding member (not shown) that is rotatable within a predetermined angular range with the Y direction as its axis of rotation. Counter electrodes 23a and 23b are positioned in the portion of the housing 21 of the spatial light modulator 20r that faces the +Z side of each spatial light modulation element 22. When a predetermined voltage is applied to the counter electrodes 23a and 23b from a modulation control unit 24 (not shown, see Figure 1), each spatial light modulation element 22 is set to an angular position rotated by a predetermined angle according to the voltage applied to the opposing counter electrodes 23a and 23b.

[0070] A reflective surface 22R is formed on the -Z side surface of each spatial light modulation element 22. In the operating state shown in Figure 6, when voltage is applied to the counter electrodes 23a and 23b, some of the spatial light modulation elements 22c among the multiple spatial light modulation elements 22 have their reflective surfaces 22Rc positioned parallel to the array plane DP. On the other hand, some of the spatial light modulation elements 22d among the multiple spatial light modulation elements 22 have their reflective surfaces 22Rd positioned rotated by an angle φ with the Y direction as the center of rotation from the array plane DP.

[0071] The illumination light (see Figure 1) irradiated onto the spatial light modulation element 22c is reflected approximately in the -Z direction by the reflective surface 22Rc parallel to the array plane DP, and enters the objective lens 15 as reflected light RR. It then passes through the opening 16o of the detection aperture diaphragm 16, through the imaging lens 17, and reaches the imaging unit 18 (both see Figure 1), where it forms an image of the spatial light modulation element 22c on the imaging surface 19.

[0072] On the other hand, the illumination light irradiated onto the spatial light modulation element 22d, which has been rotated by an angle φ, is reflected by the reflective surface 22Rc in a direction approximately 2φ away from the -Z direction to the -X direction, and enters the objective lens 15 as reflected light RO. At least a portion of this reflected light RO is then shielded by the detection aperture diaphragm 16.

[0073] Furthermore, as described above, since the illumination light ILb irradiated onto the array surface DP has a predetermined illumination NA, the reflected light RR and reflected light RO are also emitted in directions that spread out within a predetermined angular range from the direction described above. Therefore, on the imaging surface 19 of the imaging unit 18, the image intensity of the portion corresponding to the spatial light modulation element 22d having a reflective surface 22Rd rotated with respect to the array plane DP decreases according to the rotation angle of the reflective surface 22Rd from the array plane DP.

[0074] In other words, there is a predetermined correspondence between the rotation angle φ of the reflective surface 22Rd of each region of the array plane DP from the array plane DP and the detected light amount detected as the light amount of the image of each region of the array plane DP by each imaging pixel included in the imaging unit 18. Therefore, the control unit 25 of the measuring device 1 can also calculate positional information regarding the rotation angle of the reflective surface 22Rd from the array surface DP based on the amount of light detected from the image formed on the imaging surface 19 and detected by the imaging unit 18.

[0075] Furthermore, the rotation axis of each spatial light modulation element 22 is not limited to an axis parallel to the Y direction as described above, but may also be an axis of rotation parallel to any direction intersecting the Z axis. Furthermore, during measurement, the reflective surfaces 22R of the spatial light modulation elements 22 within a predetermined measurement area may all be rotated by the same angle from the array plane DP.

[0076] In the measurement device of the first embodiment described above, the moving mechanism 27 is used to move the spatial light modulator 20 relative to the fixed detection unit 5. However, the moving mechanism 27 may also be used to move the detection unit 5 relative to the fixed spatial light modulator 20. In other words, the moving mechanism 27 can be any moving mechanism that moves the relative position of the detection unit 5, including the detection optical system 10, with respect to the spatial light modulator 20, in the in-plane direction of the array plane DP.

[0077] (Effects of the measuring device of the first embodiment) (1) The measuring device of the first embodiment is a measuring device 1 for measuring a spatial light modulator 20 which comprises a plurality of spatial light modulation elements 22 each having a reflective surface 22R, and includes an illumination system (12-15) that irradiates light onto an array surface DP on which the reflective surfaces 22R of the plurality of spatial light modulation elements 22 are arranged, and a detection optical system 10 that forms an image of the array surface DP based on the light from the plurality of reflective surfaces 22R. Furthermore, it includes an imaging unit 18 that detects the image of the array surface DP formed by the detection optical system 10, and a control unit 25 that calculates position information of the reflective surfaces 22R of the spatial light modulation elements 22 in the normal direction (Z direction) of the array surface DP, or position information regarding the rotation angle of the reflective surfaces 22R of the spatial light modulation elements 22 from the array surface DP, based on the detected light amount, which is the amount of light of the image detected by the imaging unit 18. This configuration allows for accurate measurement of the operating state of the spatial light modulation element 22 included in the spatial light modulator 20.

[0078] (Measuring device of the second embodiment) The following describes the measuring device 1a of the second embodiment. In the following description, parts of the measuring device 1a of the second embodiment that are common with the measuring device 1 of the first embodiment described above will be denoted by the same reference numerals, and their descriptions will be omitted as appropriate. The configurations of the spatial light modulator 20, spatial light modulation element 22, and reflective surface 22R referred to in the following description are the same as those described with reference to Figures 2, 4, and 6 above.

[0079] Figure 7 is a schematic diagram showing the configuration of the measuring device 1a of the second embodiment. The measuring device 1a of the second embodiment is a device for measuring the operating state of the spatial light modulator 20, similar to the measuring device 1 of the first embodiment described above. The measuring device 1a of the second embodiment has a first detection unit 6 and a second detection unit 5a that detect an image of the array surface DP of the spatial light modulator 20 based on light from the reflective surface of the spatial light modulator 20. The second detection unit 5a has a wider detection field than the detection field of the first detection unit 6.

[0080] The measuring device 1a of the second embodiment has a moving mechanism 27, similar to the measuring device 1 of the first embodiment described above. The spatial light modulator 20 is held by a holding part 28 that constitutes the moving mechanism 27, and the holding part 28 is movable in the X direction (or further in the Y direction) along the guide part 29. The moving mechanism 27 in the second embodiment switches the positional relationship between the first detection unit 6 and the second detection unit 5a and the spatial light modulator 20 between a first positional relationship in which the spatial light modulator 20 faces the first detection unit 6, and a second positional relationship in which the spatial light modulator 20 faces the second detection unit 5a. Therefore, the moving mechanism 27 will also be referred to as the position changing mechanism 27 below.

[0081] The first detection unit 6 includes a detection light source 31, a light transmitting lens 32, a first branching element 33, a second branching element 34, an objective lens 35, an imaging lens 36, a reference lens 39, a reference reflective surface 40, a movable support unit 41, an imaging unit 37, and a first control unit 42, all located within the area enclosed by the dashed line in Figure 7.

[0082] The second detection unit 5a has, for example, a configuration similar to the detection unit 5 (see Figure 1) included in the measuring device 1 of the first embodiment described above. Therefore, the second detection unit 5a has a second detection optical system 10a and a second control unit 25a, similar to the detection optical system 10 and control unit 25 of the detection unit 5 described above. In Figure 7, the components constituting the second detection unit 5a are omitted from the illustration, except for the second detection optical system 10a and the second control unit 25a.

[0083] Similar to the control unit 25 included in the measuring device 1 of the first embodiment described above, the second control unit 25a of the second detection unit 5a calculates the position information of the reflective surface 22R of the spatial light modulation element 22 based on the detected light quantity that detected the image of the array surface DP. Therefore, the second control unit 25a can also be said to be a calculation unit.

[0084] Of the first detection unit 6, the light transmitting lens 32, the first branching element 33, the second branching element 34, and the objective lens 35 constitute a first illumination system that irradiates light onto the array surface DP of the spatial light modulation elements 22 that constitute the spatial light modulator 20. Furthermore, the objective lens 35, second branching element 34, first branching element 33, and imaging lens 36 included in the area enclosed by the dashed line constitute a first detection optical system 30 that forms an image of the array plane DP on the imaging surface 38 of the imaging unit 37, such as a solid-state image sensor.

[0085] The illumination light emitted from the detection light source 31 passes through the illumination optical path PIL, is roughly parallelized by the light transmitting lens 32, enters the first branching element 33, is reflected by the branching surface 33s of the first branching element 33, and then enters the second branching element 34. The illumination light is then amplitude-split by the branching surface 34s of the second branching element 34 into detection light, which is the light that passes through the branching surface 34s and goes through the detection optical path PDT, and reference light, which is the light that is reflected by the branching surface 34s and goes through the reference optical path PRF.

[0086] The detection light passing through the detection light path PDT is focused by the objective lens 35 and irradiated onto the array plane DP of the spatial light modulator 20. The detection light is then reflected by the array plane DP and passes again through the objective lens 35 and the detection light path PDT to reach the second branching element 34.

[0087] The reference light passing through the reference optical path PRF is focused by the reference lens 39 and irradiated onto the reference reflective surface 40. The reference light is then reflected by the reference reflective surface 40 and passes again through the reference lens 39 and the reference optical path PRF to reach the second branching element 34. The detection light transmitted through the branching surface 34s of the second branching element 34 and the reference light reflected by the branching surface 34s of the second branching element 34 are combined into a single light beam, pass through the imaging optical path PIM, are focused by the imaging lens 36, and enter the imaging surface 38 of the imaging unit 37.

[0088] In other words, among the components constituting the first detection unit 6, the second branching element 34, objective lens 35, imaging lens 36, reference lens 39, reference reflective surface 40, and movable support part 41 constitute a so-called interference microscope unit. Therefore, when the difference in optical path length between the detection optical path PDT and the reference optical path PRF is less than or equal to the coherence length of the illumination light emitted from the detection light source 31, an image (interference image) is formed on the imaging surface 38 by amplitudewise interference between the image of the array plane DP and the image of the reference reflective surface 40. The interference image of the array plane DP and the reference reflective surface 40 is detected by the imaging unit 37, that is, it is photoelectrically converted into an electrical signal and transmitted to the first control unit 42 as an image signal S4.

[0089] The position (X position) of the reference reflective surface 40 along the ±X direction, which is the direction of propagation of the reference optical path PRF, is movable by the movable support unit 41 that holds the reference reflective surface 40. As the reference reflective surface 40 moves in the X direction, the optical path length of the reference optical path PRF changes, causing the intensity of the interference image between the array plane DP and the reference reflective surface 40 to fluctuate. The control signal S5 is sent to the movable support unit 41, and the image signal S4 detected by the imaging unit 37 is processed while the X position of the reference reflective surface 40 is changed. The first control unit 42 sends the control signal S5 to the movable support unit 41 and processes the image signal S4 detected by the imaging unit 37 while the X position of the reference reflective surface 40 is changed.

[0090] The first control unit 42 measures the Z position of the reflective surface 22R of a spatial light modulation element 22 located on the array plane DP, based on the change in the intensity of the interference image between the image of the reflective surface 22R and the image of the reference reflective surface 40, and the X position of the reference reflective surface 40. The aforementioned interference microscope units (34-36, 39-41) and the first control unit 42 function as a position measurement unit that measures the position information of the Z-direction of the reflective surface 22R of the spatial light modulation element 22.

[0091] Furthermore, the configuration of the position measurement unit is not limited to the configuration of the interference microscope unit (34-36, 39-41) described above. For example, instead of moving the reference reflective surface 40 in the X direction by the movable support part 41, the optical path length of the detection optical path PDT may be changed by moving the entire first detection unit 6 in the Z direction. Alternatively, a conjugate surface with respect to the array surface DP may be formed within the first detection optical system 30, and a Nipkoh disk (Nipkoh filter) may be placed on that conjugate surface, thereby making the first detection optical system 30 function as a position measurement unit.

[0092] The first detection unit 6 may have a high resolution because it individually measures the Z position of the reflective surface 22R of one spatial light modulation element 22. For this reason, the numerical aperture NA1 on the spatial light modulator 20 side of the first detection optical system 30 may be set to be larger than the numerical aperture NA2 on the spatial light modulator 20 side of the second detection optical system of the second detection unit 5a.

[0093] The detection light source 31 may be an LED, for example. Furthermore, if the configuration using the Nipkoh disk described above is used, the detection light source 31 may be a laser light source. The light transmitting lens 32, the objective lens 35, and the imaging lens 36 are not limited to the number of lenses shown (2), but may include any number of lenses, and may all include a reflective optical system. The first branching element 33 and the second branching element 34 are composed of a beam splitter or a half-mirror made of a flat glass plate, similar to the branching element 14 in the first embodiment described above.

[0094] Prior to measurement, the first control unit 42 sends a control signal S3 to the spatial light modulator 20 to set the position of the reflective surface 22R of the spatial light modulation element 22 to be measured to a predetermined designated position. The control signal S3 is the same control signal S1 that is transmitted from the control unit 25 of the detection unit 5 to the spatial light modulator 20 in the measurement device 1 of the first embodiment described above.

[0095] As a result, the first detection unit 6, including the first control unit 42, can detect the difference between the above-mentioned designated position of the reflective surface 22R of the spatial light modulation element 22 and the measured position of the reflective surface 22R, that is, the actual set position of the reflective surface 22R, as a detection result.

[0096] The first detection unit 6, including the first control unit 42, may, by means of the control signal S3, set a predetermined reflective surface 22R to one of several different designated positions and detect the actual set position of the reflective surface 22R at each position. As a result, the first control unit 42 may detect the position setting relationship FR shown in Figure 3 as the detection result.

[0097] The first detection unit 6 may detect the position setting relationship FR over the entire range of the designated position of the spatial light modulation element 22, or it may detect the position setting relationship FR only over a portion of the range of the designated position of the spatial light modulation element 22.

[0098] The first control unit 42 in the first detection unit 6 may transmit the detection result of the position setting relationship FR, etc., as an information signal S6 to the second control unit 25a in the second detection unit 5a. The second control unit 25a in the second detection unit 5a may also use this detection result of the position setting relationship FR, etc., to calculate the position difference H1 described above.

[0099] Specifically, in the second detection unit 5a having the same configuration as the detection unit 5 described above, the specified position of the reflective surface 22R of the spatial light modulation element 22, which is specified during measurement, may be a corrected position based on the detection results such as the position setting relationship FR received from the first detection unit 6.

[0100] (Effects of the measuring device of the second embodiment) (2) The measuring device 1a of the second embodiment described above includes a first detection unit 6 that detects light from the reflective surfaces 22R of a spatial light modulator 20 having a plurality of spatial light modulation elements 22 having reflective surfaces 22R arranged on an array plane DP, and a second detection unit 5a that detects light from the reflective surfaces 22R and has a wider detection field than the first detection unit 6. Furthermore, it includes a position changing mechanism 27 that changes the positional relationship between the first detection unit 6 and the second detection unit 5a and the spatial light modulator 20 to either a first positional relationship in which the spatial light modulator 20 faces the first detection unit 6, or a second positional relationship in which the spatial light modulator 20 faces the second detection unit 5a. With this configuration, the first detection unit 6 can accurately measure spatial light modulation elements 22 that are arranged in a relatively narrow area within the array plane DP of the spatial light modulation elements 22, while the second detection unit 5a can simultaneously and quickly measure a large number of spatial light modulation elements 22 that are arranged in a relatively wide area.

[0101] Incidentally, if there are manufacturing errors in the spatial light modulator 20, the correspondence relationship RL1 shown in Figure 5, which is the relationship between the intensity of specularly reflected light DLa0 from a predetermined area of ​​the array surface DP and the position difference H1 of the spatial light modulator 22, may deviate from the relationship expressed by equation (1) above. In this case, there is a risk that errors may occur in the measurement value of the position difference H1 of the spatial light modulator 22 by the second detection unit 5a.

[0102] In the measuring device 1a of the second embodiment, as described above, the first detection unit 6 can accurately measure (detect) the Z position (actual set position) of the reflective surface 22R of a predetermined spatial light modulation element 22 within the array plane DP of the spatial light modulation element 22. As a result, as will be explained below, the first detection unit 6 and the second detection unit 5a can be used to accurately measure the actual correspondence relationship RL1 between the intensity of specular reflected light DLa0 and the position difference H1 of the spatial light modulation element 22.

[0103] (Measurement method of the third embodiment) The measurement method of the third embodiment will now be described. The measurement method of the third embodiment is a measurement method using the measurement device 1a of the second embodiment described above. The following description also includes a description of the measurement device 1a of the second embodiment.

[0104] When measuring the correspondence relationship RL1 described above, the measuring device 1a first uses the position changing mechanism 27 to position the first region A1 (see Figure 2(a)), which is an arbitrary region within the array plane DP of the spatial light modulator 20, opposite the first detection unit 6.

[0105] In this state, the first control unit 42 of the first detection unit 6 sends a control signal S3 to the spatial light modulator 20 to set the Z positions of the spatial light modulation elements 22 arranged in the first region A1 as shown in Figure 4(a) or Figure 4(b). That is, the Z positions of the reflective surfaces 22Ra of the first group of spatial light modulation elements 22a, which are alternately arranged in the first region A1, and the reflective surfaces 22Rb of the second group of spatial light modulation elements 22b are set to differ by a predetermined specified position difference H1d (see Figure 2(c)).

[0106] The first detection unit 6 measures at least one actual set position of the reflective surface 22Ra of the first group of spatial light modulation elements 22a and at least one actual set position of the reflective surface 22Rb of the second group of spatial light modulation elements 22b. The first control unit 42 then detects a position difference H1, which is the difference between the two measured actual set positions. The position difference H1 is distance information in the Z direction between the reflective surface 22Ra and the reflective surface 22Rb.

[0107] The first control unit 42 of the first detection unit 6 transmits the detection result, which includes the specified positions of the reflective surfaces 22Ra and 22Rb and the measured actual set positions, or the specified position difference H1d between the reflective surfaces 22Ra and 22Rb and the measured position difference H1, as an information signal S6 to the second control unit 25a in the second detection unit 5a.

[0108] Next, the measuring device 1a uses the position changing mechanism 27 to position the first region A1 within the array plane DP of the spatial light modulator 20 opposite the second detection unit 5a. The spatial light modulator 20a shown by the dotted line in Figure 7 shows the operating state in which the spatial light modulator 20 is positioned opposite the second detection unit 5a, and the holding part 28a shown by the dotted line represents the holding part 28 at that time.

[0109] In this state, the second control unit 25a of the second detection unit 5a sends a control signal S1 to the spatial light modulator 20 that is the same as the control signal S3 transmitted by the first control unit 42 of the first detection unit 6 above. As a result, the reflective surfaces 22Ra of the first group of spatial light modulator elements 22a and the reflective surface 22Rb of the second group of spatial light modulator elements 22b, which are alternately arranged in the first region A1, are set to be at positions in the Z direction that are different by a predetermined specified position difference H1d, just as when they are facing the first detection unit 6. The position difference H1 between the reflective surface 22Ra and the reflective surface 22Rb at this time is known from the detection result transmitted as an information signal S6 from the first control unit 42 of the first detection unit 6.

[0110] The second detection unit 5a detects the intensity of specularly reflected light DLa0 from the first region A1 in this state, that is, the amount of light detected for the image of the first region A1 formed on the imaging surface 19 (see Figure 1). Then, the calculation unit 25C, located in the second control unit 25a of the second detection unit 5a, calculates the correspondence relationship RL1 based on the position difference H1 of the spatial light modulation element 22 detected by the first detection unit 6 and the detected light quantity, which is the intensity of the specular reflected light DLa0 detected by the second detection unit 5a. The second control unit 25a stores the calculated correspondence relationship RL1 in the storage unit 25Ma.

[0111] As an example, the correspondence relationship RL1 may be calculated by optimizing the value of the correction coefficient α or correction coefficient β in equation (3), which is a modified version of equation (1) described above. RL1 = α+β×{1+cos(4π×H1 / λ)} / 2 …(3) In other words, by determining the correction coefficient α or β in equation (3) such that the value of RL1 on the left side of equation (3) or equation (4), calculated using the position difference H1, matches the value of the detected light intensity, the correspondence based on the detection results can be determined. In this case, if the correction coefficient α is a value other than 0, the correction coefficient β may be set to 1, and if the correction coefficient β is a value other than 1, the correction coefficient α may be set to 0.

[0112] The correspondence relationship RL1 may also be calculated based on the values ​​of multiple sets of position differences H1 and reference light intensity. That is, the above measurement may be performed multiple times with the reflective surface 22Ra and the reflective surface 22Rb set to different Z positions by a specified position difference H1d, and the correction coefficient α and correction coefficient β in equation (3) above may be determined from the obtained values ​​of multiple sets of position differences H1 and reference light intensity. When determining the correction coefficient α and correction coefficient β, an optimization method such as the least squares method may be used. Furthermore, when calculating the correspondence relationship RL1 based on the values ​​of multiple sets of positional differences H1 and reference light intensity, other arbitrary functions such as power series sums may be used instead of the above equation (3).

[0113] The correspondence relationship RL1 calculated above can also be applied to spatial light modulation elements 22 arranged in regions other than the first region A1 of the array plane DP of the spatial light modulator 20. Using this correspondence relationship RL1, the positional difference H1 of spatial light modulation elements 22 arranged in any region other than the first region A1, such as the second region A2 shown in Figure 2(a), can be measured.

[0114] To this end, the measuring device 1a uses a position-changing mechanism 27 to position the second region A2 within the array plane DP of the spatial light modulator 20 opposite the second detection unit 5a. Then, the second control unit 25a of the second detection unit 5a sends a control signal S1 to the spatial light modulator 20, causing each of the spatial light modulation elements 22 in the second region A2 to be positioned in the same arrangement as described above, separated by a specified position difference H1d in the Z direction. That is, the multiple spatial light modulation elements 22 in the second region A2 are positioned in the same way as the arrangement in the first region A1 shown in Figure 4(a) or Figure 4(b).

[0115] In region A2, the spatial light modulation element 22 corresponding to the first group spatial light modulation element 22a shown in Figure 4(a) or Figure 4(b) is called the third group spatial light modulation element. Also, in region A2, the spatial light modulation element 22 corresponding to the second group spatial light modulation element 22b is called the fourth group spatial light modulation element.

[0116] The reflective surface 22R of the third group of spatial light modulators is positioned at a distance of a specified position difference H1d in the Z direction from the reflective surface 22R of the fourth group of spatial light modulators. Furthermore, since the position setting relationship FR by the first detection unit 6 described above was not measured for the spatial light modulation elements 22 in the second region A2, the actual position difference H1 between the reflective surface 22R of the third group of spatial light modulation elements and the reflective surface 22R of the fourth group of spatial light modulation elements is not precisely known.

[0117] The second detection unit 5a detects the intensity of specularly reflected light DLa0 from the second region A2 in this state, that is, the amount of light detected in the image of the portion of the image on the imaging surface 19 (see Figure 1) corresponding to the second region A2. The second control unit 25a of the second detection unit 5a measures the position difference H1, which is distance information in the Z direction between the reflective surface 22R of the third group of spatial light modulation elements and the reflective surface 22R of the fourth group of spatial light modulation elements, based on the detected light quantity and the correspondence relationship RL1 calculated above.

[0118] The second detection unit 5a, including the second control unit 25a, may perform the above-described measurement multiple times while varying the value of the specified position difference H1d. Then, based on the relationship between the multiple measured and calculated position differences H1 and the specified position difference H1d, it may calculate a desired specified position difference, which is the specified position difference H1d for setting the desired position difference H1.

[0119] As described above, the second detection unit 5a has a wider detection field than the first detection unit 6. When the first region A1 and the second region A2 are simultaneously within the detection field of the second detection unit 5a, the second region A2 can be measured after the first region A1 is measured by the second detection unit 5a without moving the spatial light modulator 20 using the position change mechanism 27. This shortens the measurement time. Furthermore, by measuring the wide second region A2 simultaneously, the measurement time can be shortened even further.

[0120] (Effects of the measurement method of the third embodiment) (3) The measurement method of the third embodiment described above is a measurement method using a spatial light modulator 20 that includes a plurality of spatial light modulation elements 22, each having a reflective surface 22R, wherein the reflective surface 22Ra of the first group of spatial light modulation elements 22a and the reflective surface 22Rb of the second group of spatial light modulation elements 22b are arranged alternately in a first region A1 of an array plane DP in which the reflective surfaces 22R of the plurality of spatial light modulation elements 22a are arranged, and the reflective surface 22Rb of the second group of spatial light modulation elements 22b are set to different positions in the normal direction (X direction) of the array plane DP, and the first detection unit 6 measures distance information in the normal direction between at least one of the reflective surfaces 22Ra of the first group and at least one of the reflective surfaces 22Rb of the second group. Furthermore, the imaging-type second detection unit 5a measures the reference light intensity, which is the amount of light in the image corresponding to the first region A1, and calculates the correspondence relationship RL1 between the distance in the normal direction between the first group of reflective surfaces 22Ra and the second group of reflective surfaces 22Rb and the amount of light in the image, based on the measured distance information and the reference light intensity. Furthermore, the system includes setting the reflective surfaces 22R of the third group of spatial light modulation elements (22a) and the reflective surfaces 22R of the fourth group of spatial light modulation elements (22b), which are alternately arranged in the second region A2, which is different from the first region A1, within the array plane DP, to different positions in the normal direction of the array plane DP; measuring the detected light amount, which is the amount of light in the image corresponding to the second region A2, using the second detection unit 5b; and calculating distance information in the normal direction between the reflective surface 22R of the third group of spatial light modulation elements (22a) and the reflective surface 22R of the fourth group of spatial light modulation elements (22b) in the second region A2 based on the detected light amount and the correspondence relationship RL1. While measuring the correspondence relationship RL1 using the first detection unit 6 takes a relatively long time, in this configuration, the correspondence relationship RL1 is measured for the first region A1 within the array plane DP, and when measuring other regions (second region A2) using the second detection unit 5a, this correspondence relationship RL1 can be used for measurement, thus shortening the measurement time.

[0121] (Exposure apparatus of the fourth embodiment) Figure 8 is a schematic diagram showing the configuration of the exposure apparatus 2 of the fourth embodiment. The exposure apparatus 2 of the fourth embodiment comprises the measuring device 1a of the second embodiment described above, enclosed by a dashed line in Figure 8, and an exposure unit 50. The measuring device 1a of the exposure apparatus 2 of the fourth embodiment may have any of the above-described configurations and features of the measuring device 1a of the second embodiment.

[0122] The exposure unit 50 of the exposure apparatus 2 of the fourth embodiment is a projection exposure unit that projects a light and dark pattern of light modulated by the spatial light modulator 20, as described with reference to Figures 2 and 4, onto a substrate to be exposed, such as a silicon substrate or a glass substrate, on which a photosensitive material is formed on the surface.

[0123] The measuring device 1a in the exposure apparatus 2 of the fourth embodiment has a first detection unit 6 and a second detection unit 5a, as described above. The detection field of the second detection unit is wider than the detection field of the first detection unit 6. In the exposure apparatus 2 of the fourth embodiment, the position changing mechanism 27 sets the spatial light modulator 20 to one of three positions: a first position facing the first detection unit 6, a second position facing the second detection unit 5a, and a third position facing the exposure unit 50.

[0124] In Figure 8, the dotted line indicates spatial light modulator 20b, which represents spatial light modulator 20 set to the first position, and the dotted line also indicates spatial light modulator 20a, which represents spatial light modulator 20 set to the second position. Furthermore, the dotted lines indicate the positions of the holding parts 28 when holding the spatial light modulators 20b and 20a set to the second and first positions, respectively.

[0125] The positional relationship in which the spatial light modulator 20 faces the first detection unit 6 at the first position is also called the first positional relationship. The positional relationship in which the spatial light modulator 20 faces the second detection unit 5b at the second position is also called the second positional relationship. Furthermore, the positional relationship in which the spatial light modulator 20 faces the exposure unit 50 at the third position is also called the third positional relationship.

[0126] The position changing mechanism 27 may also be used to set the spatial light modulator 20 to either the first position or the second position described above. In this case, it may further have another moving mechanism for moving the spatial light modulator 20 from the first or second position to the third position described above.

[0127] The exposure unit 50 of the exposure apparatus 2 of the fourth embodiment includes a light-transmitting lens 52, a branching element 54, an imaging optical system 55, a projection aperture diaphragm 56, a sample stage 58, a stage 59, and a third control unit 60, etc. Of these, the light-transmitting lens 52 and the branching element 14 constitute an exposure illumination optical system that illuminates the array surface DP of the spatial light modulator 20 using exposure illumination light emitted from the exposure light source 51. The branching element 54, the imaging optical system 55, and the projection aperture diaphragm 56 constitute a projection optical system 53 that projects light from the spatial light modulator 20 onto the substrate 57 to be exposed.

[0128] The exposure illumination light emitted from the exposure light source 51 is shaped by the light-transmitting lens 52 and incident on a branching element 54 such as a beam splitter. It is then reflected by the branching surface 54s of the branching element 14 and irradiated onto the array surface DP of the spatial light modulator 20. The exposure illumination light is then reflected by a plurality of reflective surfaces 22R (see Figure 2) located near the array surface DP, incident on the branching element 54 again, passes through the branching surface 54s of the branching element 14, and incident on the imaging optical system 55.

[0129] The numerical aperture on the spatial light modulator 20 side of the projection optical system 53 is determined by the projection aperture diaphragm 56 included in the imaging optical system 55. By setting the numerical aperture on the spatial light modulator 20 side of the projection optical system 53 to a predetermined value, the aforementioned first-order diffracted light and the like generated from the spatial light modulation elements 22 (see Figures 2 and 4) arranged on the array plane DP of the spatial light modulator 20 are shielded by the projection aperture diaphragm 56.

[0130] Therefore, by applying a predetermined displacement to the spatial light modulation element 22 located in a predetermined region (such as the first region A1) within the array plane DP, the amount of light transmitted through the imaging optical system 55 and irradiated onto the substrate 57 to be exposed can be locally reduced, and a light-dark pattern can be projected onto the substrate 57 to be exposed. The third control unit 60 sends a control signal S8 similar to the control signals S1 and S3 described above to the spatial light modulator 20, and applies a predetermined displacement to the predetermined spatial light modulation element 22 within the array plane DP.

[0131] In the exposure apparatus 2, the substrate to be exposed 57 is placed on a sample stage 58 located on the stage 59. The substrate to be exposed 57 can be moved on the stage 59 in the X and Y directions by the sample stage 58. In addition, the substrate to be exposed 57 can be moved a small distance in the Z direction by the sample stage 58, and can also be rotated (tilted) by a small angle with the X and Y directions as axes of rotation.

[0132] The X and Y positions of the substrate 57 to be exposed are measured by the position measuring unit 61 via the position of the scale plate 62 provided on the sample stage 58, and transmitted to the third control unit 60 as a measurement signal Sc. Based on the measurement signal Sc, the third control unit 60 sends a position control signal Sd to the sample stage 58, controlling it so that the substrate 57 to be exposed is positioned at a predetermined X and Y position. The third control unit 60 sends an exposure control signal Sb to the exposure light source 51 to control the light emission timing and amount of light emitted by the exposure light source 51.

[0133] The exposure unit 50 may be a scanning type exposure apparatus that performs exposure while scanning the substrate to be exposed 57 and the sample stage 58 relative to the projection optical system 53 in the XY plane direction. Alternatively, it may be a step-and-repeat type exposure apparatus in which exposure is performed with the substrate to be exposed 57 and the sample stage 58 fixed to the projection optical system 53, and after the exposure is completed, the substrate to be exposed 57 and the sample stage 58 are sequentially moved relative to the projection optical system 53.

[0134] The wavelength of the exposure illumination light emitted from the exposure light source 51 is, for example, 450 nm or less. For example, the wavelength of the exposure illumination light may be 193 nm. The exposure light source 51 may be incorporated inside the exposure unit 50, or it may be located outside the exposure unit 50. The exposure illumination light may be guided from the exposure light source 51 to the exposure unit 50 using a light guide member such as an optical fiber.

[0135] In the exposure apparatus 2, prior to exposure of the substrate 57 to be exposed by the exposure unit 50, the operating state of the spatial light modulator 20 may be measured using the measuring device 1a. The operating state of the spatial light modulator 20 may be measured, for example, as in the measurement method of the third embodiment described above. The second detection unit 5a, including the second control unit 25a, calculates the desired specified position difference described above for each region of the array plane DP of the spatial light modulator 20 when measuring the operating state of the spatial light modulator 20.

[0136] In other words, the second detection unit 5a, including the second control unit 25a, performs the above-described measurement multiple times while varying the value of the specified position difference H1d. Then, based on the relationship between the multiple measured and calculated position differences H1 and the specified position difference H1d, it calculates a desired specified position difference, which is the specified position difference H1d for setting the desired position difference H1, for each region of the array plane DP of the spatial light modulator 20. Here, the desired position difference H1 is, for example, a position difference that corresponds to a length of 1 / 4 of the wavelength of the exposure illumination light, which minimizes the intensity of the specularly reflected light DLa0 from the spatial light modulator 20 shown in Figure 2.

[0137] The wavelength of the detection light in the second detection unit 5a may be 1.5 times or more and 3.3 times or less the wavelength of the exposure illumination light of the exposure unit 50. That is, as described above, the detection optical system 10a of the second detection unit 5a may use light of a second wavelength λ2, which has a wavelength of 1.5 times or more and 3.3 times or less the wavelength of the exposure illumination light, to detect the image of the array plane DP for the spatial light modulator 20 used for exposure with the exposure illumination light (first wavelength λ1).

[0138] The desired specified position difference calculated for each region of the array plane DP of the spatial light modulator 20 is transmitted as an information signal S7 from the second control unit 25a of the second detection unit 5a to the exposure control unit 60. When exposing the substrate 57 to be exposed, the exposure control unit 60 sends a control signal S8 to the spatial light modulator 20 so that each spatial light modulation element 22 is positioned at the desired position difference H1, based on the desired specified position difference for each region of the array plane DP transmitted from the second control unit 25a.

[0139] Furthermore, if the spatial light modulator 20 is an angle-modulated spatial light modulator 20r (see Figure 6), the second control unit 25a of the second detection unit 5a calculates the correspondence between the position information of the reflective surface 22Rd in each region of the array plane DP as a rotation angle φ from the array plane DP and the light intensity of the image in each region. The second control unit 25a transmits this correspondence to the exposure control unit 60 as an information signal S7. In this case, the exposure control unit 60 sends a control signal S8 to control the angular position of each spatial light modulation element 22 of the spatial light modulator 20 based on this correspondence.

[0140] (Effects of the exposure apparatus of the fourth embodiment) (4) The exposure apparatus 2 of the fourth embodiment includes an exposure illumination optical system (52, 54) for illuminating a spatial light modulator 20 having a plurality of spatial light modulation elements 22 having reflective surfaces 22R arranged on an array plane DP, a projection optical system 53 for projecting light from the spatial light modulator 20 onto a substrate 57 to be exposed, a first detection unit 6 having a first detection optical system 30 for detecting light from the reflective surfaces 22R, and a second detection unit 5a having a second detection optical system 10 for detecting light from the reflective surfaces 22R, and having a wider detection field than the first detection unit 6. Furthermore, it includes a position changing mechanism that changes the positional relationship between the first detection unit 6, the second detection unit 5a, and the spatial light modulator 20 to either a first positional relationship in which the spatial light modulator 20 faces the first detection unit 6, or a second positional relationship in which the spatial light modulator 20 faces the second detection unit 5a. This configuration allows the operating state of the spatial light modulator 20 to be measured quickly and with high accuracy using the first detection unit 6 and the second detection unit 5a between exposures of the substrate 57 to be exposed by the exposure unit 50 using the spatial light modulator 20. Then, using the measurement results, the exposure unit 50 can perform high-precision exposure of the substrate 57 to be exposed. Furthermore, since the time required to measure the spatial light modulator 20 is short, it is possible to realize an exposure apparatus 2 with high exposure processing capacity, i.e., high productivity.

[0141] (Modified exposure apparatus) The exposure apparatus 2 of the fourth embodiment described above (see Figure 8) comprises an exposure unit 50 that performs exposure using a spatial light modulator 20, and the measuring apparatus 1a of the second embodiment described above. In contrast, the modified exposure apparatus is equipped with the measuring device 1 of the first embodiment described above, instead of the measuring device 1a of the second embodiment. In this case, the position change mechanism (or movement mechanism) 27 makes the spatial light modulator 20 movable between a position facing the exposure unit 50 and a position facing the measuring device 1. The same effects as those of the exposure apparatus of the fourth embodiment described above can be obtained with the modified exposure apparatus as well.

[0142] (Device manufacturing method according to the fifth embodiment) In the device manufacturing method of the fifth embodiment, a semiconductor integrated circuit, printed circuit board, display device, and other devices are manufactured using the exposure apparatus 2 of the fourth embodiment described above or a modified exposure apparatus. Figure 9 is a schematic diagram showing the steps of the device manufacturing method according to the fifth embodiment.

[0143] In step S100, a film made of a dielectric, metal, or semiconductor is formed on the surface of a substrate such as a semiconductor substrate, ceramic substrate, or glass substrate that is to be manufactured for the device. Next, in step S101, a photoresist (resist) is formed on the film formed in step S100. The substrate on which the resist is formed is the exposure substrate 57 shown in Figure 8.

[0144] Then, in step S102, an exposure pattern as a light and dark pattern is exposed to the resist on the substrate (substrate to be exposed 57) using the exposure apparatus 2 of the fourth embodiment described above, or an exposure apparatus of a modified example. Then, in step S103, the resist on which the exposure pattern has been exposed is developed to form a resist pattern. After that, in step S104, using the resist pattern as a mask, a process such as etching or ion implantation is performed on the film formed on the substrate WF or on the surface of the substrate WF. Steps S103 and S104 are steps to form a circuit pattern on the substrate based on the exposure pattern formed on the resist.

[0145] Through steps S100 to S104 described above, a single-layer circuit pattern constituting the device is formed on the substrate WF. Therefore, after the completion of step S104, the process moves to the next step, and steps S100 through S104 are repeated, thereby enabling the manufacture of devices consisting of multiple layers (semiconductor integrated circuits, printed circuit boards, display devices, etc.).

[0146] (Effects of the device manufacturing method of the fifth embodiment) The device manufacturing method of the fifth embodiment includes forming a resist on the surface of a substrate (substrate to be exposed 57), forming an exposure pattern using the exposure apparatus 2 of the fourth embodiment or an exposure apparatus of a modified example, and forming a circuit pattern based on the exposure pattern. This enables exposure of substrates using highly accurate and productive exposure equipment, such as the exposure apparatus 2, thereby allowing for the manufacture of high-performance devices with high productivity.

[0147] The present invention is not limited to the above. Other embodiments conceivable within the scope of the technical idea of ​​the present invention are also included within the scope of the present invention. This embodiment may combine all or part of the above embodiments. [Explanation of symbols]

[0148] 1,1a: Measuring device, 2: Exposure device, 5: Detection unit, 6: First detection unit, 5a: Second detection unit, 10: Detection optical system, 10a: Second detection optical system, 14: Branching element, 15: Objective lens, 16: Detection aperture diaphragm, 18: Imaging unit, 19: Imaging surface, 20: Spatial light modulator, DP: Array surface, 22: Spatial light modulation element, 22R: Reflecting surface, 25: Control unit (calculation unit), 25M: Memory unit, 25C: Calculation unit, 27: Position change mechanism (movement mechanism), 30: First detection optical system, 42: First control unit, 50: Exposure unit, 51: Exposure light source, 55: Imaging optical system, 59: Stage, 60: Exposure control unit

Claims

1. A spatial light modulator includes an illumination system that irradiates light onto an array surface in which the reflective surfaces of multiple spatial light modulators, each having a reflective surface, are arranged, A detection optical system that forms an image of the array surface based on light from multiple reflective surfaces, An imaging unit for detecting the image of the array surface formed by the detection optical system, The system includes a calculation unit that calculates positional information of the spatial light modulation element based on the detected light quantity, which is the amount of light in the image detected by the imaging unit, The position information of the spatial light modulation element is the position information of the reflective surface of the spatial light modulation element in the direction normal to the array surface. The imaging unit is It includes multiple pixels, including the first pixel, and The amount of light in the image formed by a plurality of first spatial light modulation elements, each having a reflective surface, included in the spatial light modulator, is detected by the first pixel. The calculation unit calculates position information of the first spatial light modulation element based on the amount of light detected by the first pixel, and the position information of the first spatial light modulation element is the position information of the reflective surface of the first spatial light modulation element in the direction normal to the array surface. The aforementioned arithmetic unit, It has a storage unit that stores the correspondence between the light intensity of the image and the positional information of the spatial light modulation element, Based on the correspondence stored in the memory unit, the position information of the spatial light modulation element is calculated from the detected light quantity of the image. The aforementioned correspondence is a correspondence based on the wavelength of light. Measuring device.

2. An illumination system that illuminates an array surface in which the reflective surfaces of a plurality of spatial light modulators, each having a reflective surface, are arranged, included in a spatial light modulator, A detection optical system that forms an image of the array surface based on light from multiple reflective surfaces, An imaging unit for detecting the image of the array surface formed by the detection optical system, The system includes a calculation unit that calculates positional information of the spatial light modulation element based on the detected light quantity, which is the amount of light in the image detected by the imaging unit, The position information of the spatial light modulation element is the position information of the reflective surface of the spatial light modulation element in the direction normal to the array surface. The imaging unit is It includes multiple pixels, including the first pixel, and The amount of light in the image formed by a plurality of first spatial light modulation elements, each having a reflective surface, included in the spatial light modulator, is detected by the first pixel. The calculation unit calculates position information of the first spatial light modulation element based on the amount of light detected by the first pixel, and the position information of the first spatial light modulation element is the position information of the reflective surface of the first spatial light modulation element in the direction normal to the array surface. For the spatial light modulator used for light of the first wavelength λ1, The detection optical system is a measuring device that detects the image using light of a second wavelength λ2, which has a wavelength of 1.5 times or more and 3.3 times or less than the first wavelength λ1.

3. An illumination system that illuminates an array surface in which the reflective surfaces of a plurality of spatial light modulators, each having a reflective surface, are arranged, included in a spatial light modulator, A detection optical system that forms an image of the array surface based on light from multiple reflective surfaces, An imaging unit for detecting the image of the array surface formed by the detection optical system, The system includes a calculation unit that calculates positional information of the spatial light modulation element based on the detected light quantity, which is the amount of light in the image detected by the imaging unit, The position information of the spatial light modulation element is the position information of the reflective surface of the spatial light modulation element in the direction normal to the array surface. The imaging unit is It includes multiple pixels, including the first pixel, and The amount of light in the image formed by a plurality of first spatial light modulation elements, each having a reflective surface, included in the spatial light modulator, is detected by the first pixel. The calculation unit calculates position information of the first spatial light modulation element based on the amount of light detected by the first pixel, and the position information of the first spatial light modulation element is the position information of the reflective surface of the first spatial light modulation element in the direction normal to the array surface. The detection optical system is a measuring device that includes an aperture that allows specularly reflected light from the reflective surface to pass through and blocks the +1st order diffracted light and -1st order diffracted light.

4. In the measuring device according to any one of claims 1 to 3, The aforementioned arithmetic unit, The reflective surfaces of the multiple spatial light modulation elements are located at the same position in the direction normal to the array surface, A measuring device that calculates positional information of the spatial light modulation element from the detected light quantity, based on a reference light quantity which is the light quantity of the image of the reflective surface in a first state that is parallel to the array plane.

5. In the measuring device according to any one of claims 1 to 4, The numerical aperture NA on the spatial light modulator side of the detection optical system is When P is the period of the arrangement of the multiple spatial light modulation elements and λ2 is the wavelength of light detected by the detection optical system, λ2 / (5×P) < NA < √2×λ2 / (2×P) A measuring device that satisfies the requirements.

6. In the measuring device according to any one of claims 1 to 5, A measuring device in which the product of the outer diameter D [mm] of the detection field on the spatial light modulator side of the detection optical system and the numerical aperture NA on the spatial light modulator side of the detection optical system is 0.5 or more.

7. In the measuring device according to any one of claims 1 to 6, A measuring device further comprising a moving mechanism for moving the relative position of the detection optical system with respect to the spatial light modulator in the in-plane direction of the array surface.

8. An illumination optical system for illuminating the spatial light modulator having a plurality of spatial light modulation elements having reflective surfaces arranged on the array plane, A projection optical system that projects light from the spatial light modulator onto the substrate to be exposed, A measuring device according to any one of claims 1 to 7, An exposure apparatus equipped with the following features.

9. Forming a resist on the surface of the substrate, Exposing the resist to an exposure pattern using the exposure apparatus described in claim 8, To form a circuit pattern based on the exposure pattern, A device manufacturing method including the following.

Images