Illumination optical system, exposure apparatus, and production method of article

Abstract

To provide a light source device advantageous for coping with various illumination modes.SOLUTION: An illumination optical system having a light source device including a plurality of LED elements superposes light from the plurality of LED elements on a pupil plane of the illumination optical system to form a desired light intensity distribution on the pupil plane, wherein the light source device has: a first LED element for generating a first light emission distribution on a light emission plane; a second LED element for generating a second light emission distribution different from the first light emission distribution on a light emission plane; and a control part for controlling light emission of the first LED element and the second LED element. The control part controls light emission of the first LED element and light emission of the second LED element so that a relative intensity of a light intensity distribution formed on the pupil plane by the first LED element and a light intensity distribution formed on the pupil plane by the second LED element illuminates the pupil plane by a plurality of mutually different illumination modes.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to an illumination optical system, an exposure apparatus, and a method for manufacturing an article. [Background technology]

[0002] An exposure apparatus is an apparatus that transfers a pattern of an original (reticle or mask) onto a photosensitive substrate (such as a wafer or glass plate with a resist layer formed on its surface) via a projection optical system in the lithography process, which is a manufacturing process for semiconductor devices and liquid crystal display devices. For example, in recent years, projection exposure apparatuses that transfer patterns onto liquid crystal display devices are required to expose a larger area pattern on the mask onto the substrate at once. To meet this demand, a step-and-scan scanning projection exposure apparatus has been proposed that can obtain high resolution and expose a large screen. This scanning exposure apparatus transfers a pattern illuminated by a slit light beam onto the substrate by a scanning operation via a projection optical system.

[0003] For example, mercury lamps are used as the light source for exposure equipment, but in recent years, there is a growing expectation that mercury lamps will be replaced by light-emitting diodes (LEDs), which are solid-state light-emitting elements. LEDs have the advantage of being energy-saving and long-lasting, since the time it takes for the light output to stabilize after current is passed through the board circuit that controls the light emission is short and there is no need to emit light constantly like with mercury lamps.

[0004] In addition, in the case of exposure equipment, Resolution Enhancement Techniques (RET) are known as a technique for improving the transfer performance of fine patterns. One type of RET is modified illumination, which optimizes the angular distribution of light that illuminates each point on the mask. For example, annular illumination, in which the effective light source distribution is annular, is used to improve the resolution performance of fine patterns.

[0005] Patent Document 1 discloses a method for realizing annular illumination by using multiple LED elements that emit light in an annular shape. This allows for modified illumination without reducing the efficiency of LED usage. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2021-189397 A Summary of the Invention [Problem to be solved by the invention]

[0007] However, the method disclosed in Patent Document 1 is premised on the use of an LED element that emits light in an annular shape, and therefore cannot use illumination modes other than annular illumination, which is an illumination mode in which the light intensity distribution of the illumination optical system is annular (for example, illumination in which the light intensity distribution of the illumination optical system is circular), which can be disadvantageous in that its applications are limited.

[0008] SUMMARY OF THE PRESENT EMBODIMENTS An object of the present invention is to provide an illumination optical system that is advantageous in terms of handling various illumination modes. [Means for solving the problem]

[0009] In order to achieve the above-mentioned object, an illumination optical system as one aspect of the present invention is an illumination optical system having a light source device including a plurality of LED elements, and the illumination optical system superimposes light from the plurality of LED elements on a pupil plane of the illumination optical system to form a desired light intensity distribution on the pupil plane, the light source device having a first LED element whose light-emitting surface forms a first light-emitting distribution, a second LED element whose light-emitting surface forms a second light-emitting distribution different from the first light-emitting distribution, and a control unit that controls light emission of the first LED element and the second LED element, and the control unit controls the light emission of the first LED element and the light emission of the second LED element so as to illuminate the pupil plane using a plurality of illumination modes in which the relative intensities of the light intensity distribution formed on the pupil plane by the first LED element and the light intensity distribution formed on the pupil plane by the second LED element are different from each other. Effect of the Invention

[0010] According to the present invention, it is possible to provide an illumination optical system that is advantageous in terms of handling various illumination modes. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a schematic diagram showing a configuration of an exposure apparatus. [Diagram 2] FIG. 2 is a schematic diagram showing a configuration of an illumination optical system. [Diagram 3] FIG. 2 is a schematic diagram showing a configuration of a light source device. [Figure 4] FIG. 2 is a diagram showing the light emission distribution of the light emitting surface of an LED element. [Diagram 5] FIG. 4 is a diagram showing a light intensity distribution on a predetermined surface. [Figure 6] FIG. 13 is a diagram showing a light source device provided with a cooler. [Figure 7] FIG. 2 is a diagram showing the overall configuration of a light source device. [Figure 8] 1 is a flowchart of a method for manufacturing an article. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to refer to the same components, and duplicated explanations will be omitted.

[0013] 1 is a schematic diagram showing the configuration of an exposure apparatus 100. The exposure apparatus 100 is a lithography apparatus that illuminates a mask (original) 9 with light including multiple wavelength ranges and transfers a pattern of the mask 9 onto a plate (substrate) 12. The exposure apparatus 100 is an apparatus for manufacturing flat panel displays, semiconductor elements, MEMS (Micro Electro Mechanical Systems), and the like.

[0014] The exposure apparatus 100 has an illumination optical system 10 that illuminates a mask 9, which is an illumination surface, with light from a light source, and a projection optical system 101 that projects an image of a pattern formed on the mask 9 onto a plate 12. The exposure apparatus 100 further has a mask stage 37 that holds, drives or positions the mask 9, a plate stage 38 that holds, drives or positions the plate 12, and a main controller 40. The mask 9 is placed on the object plane of the projection optical system 101, and the plate 12 is placed on the image plane of the projection optical system 101, which is a position optically conjugate with the object plane.

[0015] The exposure light emitted from the illumination optical system 10 passes through the mask 9 and is projected onto the plate 12 via the projection optical system 101. The projection optical system 101 has a trapezoidal mirror 32, a concave mirror , and a convex mirror .

[0016] 2 is a schematic diagram of the illumination optical system 10 of the exposure apparatus 100. The illumination optical system 10 has a light source device 11, a relay lens 12, an optical integrator 13, and a condenser lens optical system 15. Light emitted from the light source device 11 is collected by the relay lens 12 and irradiated onto the optical integrator 13. In terms of positional relationship, the exit surface of the light source device 11 is located near the front focal position of the relay lens 12, and the entrance surface of the optical integrator 13 is located near the rear focal position of the relay lens 12. The optical integrator 13 is, for example, a fly's eye lens, and can be composed of a number of identical lens elements. The optical integrator 13 performs wavefront division of the light on the entrance surface, and forms a multiple light source image of the light source device 11 on the exit surface. In other words, an optical image of the light source device 11 is formed on the entrance surface of each of the many lens elements that make up the optical integrator 13, which serves as a secondary light source and controls the angular distribution of the light that irradiates the mask 9. The light that has passed through the optical integrator 13 is then collected by the condenser lens optical system 15 and irradiated onto the mask 9.

[0017] Next, the light source device in this embodiment will be described. FIG. 3 is a schematic diagram showing the configuration of the optical device 11. The light source device 11 has a plurality of LED elements 21 (21a, 21b), a first lens 23 (23a, 23b) and a second lens 24 (24a, 24b) having a curvature at a position corresponding to the plurality of LED elements 21, and a control unit 28. The first lens 23 and the second lens 24 are also called a lens array because a plurality of microlenses can be integrally formed. The light emitted from the LED element 21 is condensed by the first lens 23 and the second lens 24 so as to have directionality. The control unit 28 can control the lighting of the LED elements 21 individually or for each unit consisting of a specific number. In addition, the control unit 28 can control the amount of current flowing through the LED elements 21 individually or for each unit. This makes it possible to control the light emission of the plurality of LED elements 21.

[0018] In this embodiment, the LED element 21a (first LED element) and the LED element 21b (second LED element) have different light emission distributions on their light emitting surfaces. As shown in FIG. 4(a), the LED element 21a emits light so that its light emitting surface has a first light emission distribution. The first light emission distribution may be a light emission distribution in which light is emitted so that the center of the light emitting surface has a peak. The first light emission distribution may also be a light emission distribution in which light is emitted in a circular shape. The first light emission distribution may also be a light emission distribution in which light is emitted so as to be a normal distribution.

[0019] 4(b), the LED element 21b emits light such that the light emitting surface has a second light emitting distribution different from the first light emitting distribution. The second light emitting distribution may be a light emitting distribution that does not have a peak at the center of the light emitting surface. The second light emitting distribution may be a light emitting distribution that emits light in an annular shape.

[0020] In general, the light emission distribution of the light-emitting surface of an LED element is determined by the arrangement of the electrodes. For example, LED elements have the characteristic of emitting light where the electrodes are concentrated. In other words, by making the arrangement of the electrodes different during the manufacturing of the LED elements, the light emission distribution of the light-emitting surface can be made different between LED element 21a and LED element 21b.

[0021] In this embodiment, LED elements having different light emission distributions can be arranged for each current-controllable unit. For example, a first circuit in which a plurality of LED elements 21a are arranged in series and a second circuit in which a plurality of LED elements 21b are arranged in series can be configured to be current-controlled. This allows the control unit 28 to control the current so that the light from each of the LED elements can be superimposed on the predetermined surface A as described below, forming a desired light intensity distribution.

[0022] In this embodiment, the number of the LED elements 21a and the LED elements 21b may be the same or different. For example, when emphasis is placed on increasing the illuminance of the first illumination mode described below, the number of the LED elements 21a may be greater than the number of the LED elements 21b, and when emphasis is placed on increasing the illuminance of the second illumination mode, the number of the LED elements 21a may be less than the number of the LED elements 21b. Here, the illumination mode is a mode that illuminates the light intensity distribution on the pupil plane of the illumination optical system 10 to a desired distribution. The illumination mode is, for example, an annular illumination that makes the pupil plane of the illumination optical system 10 annular, an illumination that makes the pupil plane of the illumination optical system 10 circular, etc.

[0023] FIG. 5 is a diagram showing a light intensity distribution formed on a predetermined plane A. Here, the predetermined plane A can be the pupil plane of the illumination optical system 10. The pupil plane corresponds to the exit plane of the optical integrator 13. The plane optically Fourier transformed with respect to the plane on which the mask 9 is disposed corresponds to the pupil plane position. A diaphragm (such as a filter having a transmissive portion and a non-transmissive portion) for forming a desired light intensity distribution can be disposed at the pupil plane position. In this embodiment as well, a configuration can be adopted in which a corresponding diaphragm is disposed among a plurality of diaphragms prepared according to a change in the illumination mode.

[0024] 5(a) is a diagram showing a first light intensity distribution which is a light intensity distribution in a first illumination mode. In the first illumination mode, a circular light intensity distribution with a diameter β can be formed on a predetermined surface A. At this time, the LED element 21a is controlled by the control unit 28 so as to emit light and the LED element 21b not to emit light.

[0025] 5(b) is a diagram showing a second light intensity distribution in the second illumination mode. In the second illumination mode, a light intensity distribution in an annular shape, in which a circle of diameter δ is hollowed out by a circle of diameter θ, can be formed on the predetermined surface A. At this time, the control unit 28 controls the LED element 21b to emit light and the LED element 21a not to emit light.

[0026] 5(c) is a diagram showing a third light intensity distribution in the third illumination mode. In the third illumination mode, a circular light intensity distribution with a diameter α can be formed on the predetermined surface A. At this time, the control unit 28 controls the LED elements 21a and 21b to emit light.

[0027] In this embodiment, it is preferable that β=θ and δ=α. However, they do not have to match exactly, and a deviation of about 10% is acceptable. The light intensity distribution formed on the predetermined surface A in the third illumination mode is the sum of the light intensity distribution formed on the predetermined surface A in the first illumination mode and the light intensity distribution formed on the predetermined surface A in the second illumination mode.

[0028] In this embodiment, not emitting light (OFF) includes not only completely emitting no light, but also emitting light to an extent that does not significantly affect the formation of the light intensity distribution. For example, in the first lighting mode, even if the LED element 21b emits light at 10% or less of the light emission amount of the LED element 21a, the LED element 21b is expressed as not emitting light (OFF) because the influence of the LED element 21a is dominant.

[0029] In the exposure apparatus 100, different illumination modes are required depending on changes in the production process. Therefore, it is useful for the user to be able to switch between illumination modes as described above. For example, the third illumination mode (also called large σ illumination) has a higher maximum light amount than the first and second illumination modes, and therefore can be selected for production processes that require high illuminance. The second illumination mode (also called annular illumination) can illuminate the mask 9 obliquely, and therefore can be selected for production processes that require high resolution. The first illumination mode (also called small σ illumination) can be selected for a specific production process, such as the formation of contact holes.

[0030] That is, in this embodiment, illumination is performed using a plurality of illumination modes in which the relative intensities of the light intensity distribution formed by the LED element 21a (first LED element) on a predetermined surface A (pupil surface) and the light intensity distribution formed by the LED element 21b (second LED element) on the predetermined surface A are different from each other. The control unit 28 controls the light emission of the LED element 21a and the light emission of the LED element 21b so as to illuminate the predetermined surface A using the above-mentioned plurality of illumination modes. The control unit 28 can select one of the plurality of illumination modes based on the acquired information on the target light intensity distribution.

[0031] In the present embodiment, the control unit 28 can change the light intensity distribution on the predetermined surface A by switching between the first illumination mode and the second illumination mode. Also, the control unit 28 can change the light intensity distribution on the predetermined surface A by switching between the first illumination mode or the second illumination mode and the third illumination mode.

[0032] As a comparative example, a case where multiple illumination modes are realized using LED elements all having the same light emission distribution will be described. For example, when realizing the first illumination mode or the second illumination mode, it is necessary to achieve a desired light intensity distribution by using an aperture arranged at the pupil plane position. However, in that case, it is necessary to block a large amount of light by the aperture, which reduces the light utilization efficiency. In addition, heat generation due to the blocked light can also be an issue.

[0033] The present embodiment is advantageous over the comparative example in that it can improve the light utilization efficiency when implementing the first illumination mode and the second illumination mode. It can also be advantageous over the comparative example in that it can reduce the amount of heat generated. The present embodiment can be an advantageous technique in dealing with various illumination modes.

[0034] In this embodiment, the control unit 28 can change the lighting mode based on an instruction from a higher-level control unit (e.g., the main control unit 40). For example, when the main control unit 40 receives an instruction to change the lighting mode from a user, the main control unit 40 can instruct the control unit 28 to change the lighting mode. Also, the control unit 28 may be configured to directly accept a change in the lighting mode from the user. That is, the control unit 28 can control to switch the lighting mode based on information on the target light intensity distribution acquired by the main control unit 40 or by itself.

[0035] When a large number of LED elements 21 are used in the exposure apparatus 100, heat generated from the LED elements 21 can become an issue. Next, a cooler 25 that cools the light source device 11 will be described.

[0036] Fig. 6 is a diagram for explaining the cooler 25. The LED elements 21 are mounted on a substrate 22 (electrical substrate), and the cooler 25 is provided in contact with the substrate 22. The cooler 25 can be, for example, a liquid-cooled heat sink. The cooler 25 can also be an air-cooled heat sink for natural air cooling or forced air cooling. As shown in Fig. 6, the cooler 25 can simultaneously cool both the LED elements 21a and 21b.

[0037] FIG. 7 is a schematic diagram showing the entire light source device 11. The light source device 11 may have a plurality of substrates 22a on which the LED elements 21a are arranged and a plurality of substrates 22b on which the LED elements 21b are arranged. The control unit 28 may control the amount of current flowing through the LED elements 21 for each substrate shown in FIG. 7. The substrates 22a and 22b may be arranged freely, but may be arranged alternately as shown in FIG. 7. By arranging them in this way, it is possible to prevent the LED elements from being densely packed together, and the cooling efficiency is improved in the first lighting mode or the second lighting mode. In addition, by improving the cooling efficiency, it is possible to pass a larger current in the first lighting mode or the second lighting mode, and the illuminance may be increased.

[0038] <Embodiments of the method for manufacturing an article> The method for manufacturing an article according to an embodiment of the present invention is suitable for manufacturing articles such as flat panel displays (FPDs), semiconductor devices, sensors, and optical elements. FIG. 8 is a flow chart of the method for manufacturing an article according to this embodiment. The method for manufacturing an article according to this embodiment includes a step of forming a latent image pattern by exposure using the exposure apparatus 100 described above on a photosensitive material applied on a substrate to obtain an exposed substrate (exposure step, step S11). The method also includes a step of developing the substrate exposed in this step to obtain a developed substrate (development step, step S12). Furthermore, the manufacturing method includes other well-known steps (oxidation, film formation, deposition, doping, planarization, etching, resist stripping, dicing, bonding, packaging, etc.) (processing step, step S13). The method for manufacturing an article according to this embodiment is advantageous in at least one of the performance, quality, productivity, and production cost of the article compared to conventional methods.

[0039] Although the preferred embodiments of the present invention have been described above, it goes without saying that the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist of the present invention.

[0040] The disclosure of this specification includes at least the following light source device, exposure apparatus, and article manufacturing method.

[0041] (Item 1) An illumination optical system having a light source device including a plurality of LED elements, the illumination optical system being configured to superimpose light from the plurality of LED elements on a pupil plane of the illumination optical system to form a desired light intensity distribution on the pupil plane, The light source device is A first LED element having a light emitting surface with a first light emitting distribution; A second LED element having a light emitting surface that has a second light emitting distribution different from the first light emitting distribution; A control unit that controls light emission of the first LED element and the second LED element; having an illumination optical system characterized in that the control unit controls the light emission of the first LED element and the light emission of the second LED element so as to illuminate the pupil plane using a plurality of illumination modes in which the relative intensities of the light intensity distribution formed on the pupil plane by the first LED element and the light intensity distribution formed on the pupil plane by the second LED element are different from each other.

[0042] (Item 2) The plurality of lighting modes include: a first illumination mode in which the first LED element is caused to emit light and the second LED element is caused to emit light to an amount equal to or less than 10% of the amount of light emitted by the first LED element, thereby forming a first light intensity distribution on the pupil plane; a second illumination mode in which the second LED element is caused to emit light and the first LED element is caused to emit light at an amount equal to or less than 10% of the amount of light emitted by the second LED element, thereby forming a second light intensity distribution on the pupil plane; Including, 2. The illumination optical system described in item 1, wherein the control unit controls to switch between the first illumination mode and the second illumination mode.

[0043] (Item 3) the plurality of illumination modes include a first illumination mode in which a first light intensity distribution is formed on the pupil plane by causing the first LED element to emit light and the second LED element to not emit light, and a second illumination mode in which a second light intensity distribution different from the first light intensity distribution is formed on the pupil plane by causing the second LED element to emit light without causing the first LED element to emit light, 2. The illumination optical system described in item 1, wherein the control unit controls to switch between the first illumination mode and the second illumination mode.

[0044] (Item 4) The plurality of lighting modes include: A third illumination mode is further included in which a third light intensity distribution different from the first light intensity distribution and the second light intensity distribution is formed on the pupil plane by causing the first LED element and the second LED element to emit light, 4. The illumination optical system according to item 2 or 3, wherein the control unit controls switching between the first illumination mode or the second illumination mode and the third illumination mode.

[0045] (Item 5) 5. The illumination optical system according to item 4, wherein the third light intensity distribution is a sum of the first light intensity distribution and the second light intensity distribution.

[0046] (Item 6) the first light emission distribution is a light emission distribution in which the center of the light emitting surface of the first LED element emits light having a peak, The second light emission distribution is a light emission distribution in which the center of the light emitting surface of the second LED element does not have a peak. 6. An illumination optical system according to any one of items 1 to 5,

[0047] (Item 7) the first light emission distribution is a light emission distribution that emits light in a circular shape, The second light emission distribution is a light emission distribution that emits light in an annular shape. 7. The illumination optical system according to item 6,

[0048] (Item 8) 8. The illumination optical system described in item 7, wherein the first light emission distribution is a light emission distribution that emits light so as to be a normal distribution.

[0049] (Item 9) The illumination optical system described in any one of items 1 to 8, characterized in that the control unit selects one of a plurality of illumination modes based on the acquired information on the light intensity distribution of the target.

[0050] (Item 10) 10. The illumination optical system according to any one of items 1 to 9, further comprising a cooler for cooling a substrate on which the plurality of LED elements are mounted.

[0051] (Item 11) The light source device includes: Further comprising a lens array provided corresponding to each of the plurality of LED elements and configured to collect light from each of the plurality of LED elements. 11. The illumination optical system according to any one of items 1 to 10,

[0052] (Item 12) 12. The illumination optical system according to any one of items 1 to 11, further comprising an optical integrator arranged so that an exit surface is located on the pupil surface.

[0053] (Item 13) 13. The illumination optical system according to any one of items 1 to 12, further comprising a diaphragm on the pupil plane that is variably arranged depending on the illumination mode of the light source device.

[0054] (Item 14) 14. An exposure apparatus that illuminates an original with light from an illumination optical system according to any one of items 1 to 13 and forms a pattern of the original on a substrate, comprising: an exposure apparatus comprising: a projection optical system that projects light that has passed through the original onto the substrate;

[0055] (Item 15) An exposure step of exposing a substrate using the exposure apparatus according to item 14 to obtain an exposed substrate; a developing step of developing the exposed substrate to obtain a developed substrate, A method for manufacturing an article, comprising the steps of: manufacturing an article from the developed substrate.

[0056] (Item 16) A first LED element having a circular light-emitting surface; a second LED element having a light emitting surface that emits light in a ring shape; a control unit that controls light emission of the first LED element and the second LED element; having The control unit controls the light emission of the first LED element and the light emission of the second LED element so as to illuminate the specified surface using a plurality of lighting modes in which the relative intensities of the light intensity distribution formed on the specified surface by the first LED element and the light intensity distribution formed on the specified surface by the second LED element are different from each other. [Explanation of symbols]

[0057] 10 Illumination optical system 11 Light source device 21 LED elements 21a First LED element 21b Second LED element 28 Control Unit A Predetermined plane (pupil plane)

Claims

1. An illumination optical system having a light source device including a plurality of LED elements, the illumination optical system being configured to superimpose light from the plurality of LED elements on a pupil plane of the illumination optical system to form a desired light intensity distribution on the pupil plane, The light source device is a first LED element having a light emitting surface with a first light emission distribution; a second LED element having a light emitting surface that has a second light emitting distribution different from the first light emitting distribution; A control unit that controls light emission of the first LED element and the second LED element; having the control unit controls the light emission of the first LED element and the light emission of the second LED element so as to illuminate the pupil plane using a plurality of illumination modes in which the relative intensities of the light intensity distribution formed on the pupil plane by the first LED element and the light intensity distribution formed on the pupil plane by the second LED element are different from each other.

2. The plurality of lighting modes include: a first illumination mode in which the first LED element is caused to emit light and the second LED element is caused to emit light at an amount equal to or less than 10% of the amount of light emitted by the first LED element, thereby forming a first light intensity distribution on the pupil plane; a second illumination mode in which the second LED elements are caused to emit light and the first LED elements are caused to emit light at an amount equal to or less than 10% of the amount of light emitted by the second LED elements, thereby forming a second light intensity distribution on the pupil plane; Including, The illumination optical system according to claim 1 , wherein the control unit controls the illumination mode to be switched between the first illumination mode and the second illumination mode.

3. the plurality of illumination modes include a first illumination mode in which a first light intensity distribution is formed on the pupil plane by causing the first LED element to emit light and the second LED element to not emit light, and a second illumination mode in which a second light intensity distribution different from the first light intensity distribution is formed on the pupil plane by causing the second LED element to emit light without causing the first LED element to emit light, The illumination optical system according to claim 1 , wherein the control unit controls the illumination mode to be switched between the first illumination mode and the second illumination mode.

4. The plurality of lighting modes include: a third illumination mode in which a third light intensity distribution different from the first light intensity distribution and the second light intensity distribution is formed on the pupil plane by causing the first LED element and the second LED element to emit light; The illumination optical system according to claim 2 , wherein the control unit controls switching between the first illumination mode or the second illumination mode and the third illumination mode.

5. 5. The illumination optical system according to claim 4, wherein the third light intensity distribution is a sum of the first light intensity distribution and the second light intensity distribution.

6. the first light emission distribution is a light emission distribution in which light is emitted so as to have a peak at the center of a light emitting surface of the first LED element, The second light emission distribution is a light emission distribution in which the center of the light emitting surface of the second LED element does not have a peak.

2. The illumination optical system according to claim 1.

7. the first light emission distribution is a light emission distribution that emits light in a circular shape, The second light emission distribution is a light emission distribution that emits light in an annular shape.

7. The illumination optical system according to claim 6.

8. 8. The illumination optical system according to claim 7, wherein the first light emission distribution is a light emission distribution that emits light so as to be a normal distribution.

9. 2. The illumination optical system according to claim 1, wherein the control unit selects one of a plurality of illumination modes based on the acquired information on the light intensity distribution of the target.

10. 2. The illumination optical system according to claim 1, further comprising a cooler for cooling a substrate on which the plurality of LED elements are mounted.

11. The light source device is Further comprising a lens array provided corresponding to each of the plurality of LED elements and configured to collect light from each of the plurality of LED elements.

2. The illumination optical system according to claim 1.

12. 2. The illumination optical system according to claim 1, further comprising an optical integrator arranged so that an exit surface is located on the pupil surface.

13. 2. The illumination optical system according to claim 1, further comprising a diaphragm on the pupil plane, the diaphragm being variably disposed in accordance with an illumination mode of the light source device.

14. 14. An exposure apparatus that illuminates an original with light from an illumination optical system according to claim 1 and forms a pattern of the original on a substrate, comprising: an exposure apparatus comprising: a projection optical system that projects light that has passed through the original onto the substrate;

15. an exposure step of exposing a substrate using the exposure apparatus according to claim 14 to obtain an exposed substrate; a developing step of developing the exposed substrate to obtain a developed substrate, A method for manufacturing an article, comprising the steps of: manufacturing an article from the developed substrate.

16. A first LED element having a circular light emitting surface; A second LED element having a light emitting surface that emits light in an annular shape; a control unit that controls light emission of the first LED element and the second LED element; having the control unit controls the light emission of the first LED element and the light emission of the second LED element so as to illuminate the specified surface using a plurality of lighting modes in which the relative intensities of the light intensity distribution formed on the specified surface by the first LED element and the light intensity distribution formed on the specified surface by the second LED element are different from each other.

Images