Light source device, exposure device, and method for manufacturing articles

Abstract

To provide a light source device that is advantageous for controlling LEDs. [Solution] The device comprises a plurality of LEDs arranged on a substrate and a plurality of lenses that focus the light from the plurality of LEDs, wherein the plurality of LEDs comprises a first LED group and a second LED group that are included in different circuits from each other, the number of LEDs included in the first LED group is the same as the number of LEDs included in the second LED group, and the first LED group has at least one LED positioned away from the optical axis of the plurality of lenses.

Description

Technical Field

[0001] The present invention relates to a light source device, an exposure device, and a method for manufacturing an article.

Background Art

[0002] An exposure device is a device that transfers the pattern of a master plate (reticle or mask) to a photosensitive substrate (such as a wafer or glass plate having a resist layer formed on its surface) through a projection optical system in a lithography process, which is a manufacturing process for semiconductor devices, liquid crystal display devices, etc. For example, in a projection exposure device that transfers a pattern to a liquid crystal display device, in recent years, it has been required to perform batch exposure of a larger area pattern on a mask onto a substrate. To meet this requirement, a scanning type projection exposure device using a step-and-scan method that can obtain high resolution and expose a large screen has been proposed. This scanning type exposure device transfers a pattern illuminated by a slit light beam onto a substrate through a scanning operation via a projection optical system.

[0003] As a light source of an exposure device, for example, a mercury lamp has been used, but in recent years, it is expected to be replaced with a light emitting diode (LED: Light Emitting Diode), which is a solid light emitting element. Since the time until the light output stabilizes after flowing a current through the substrate circuit that controls light emission in an LED is short and it is not necessary to emit light constantly like a mercury lamp, it has the advantages of energy saving and long life. Patent Document 1 discloses content related to an LED light source used in an exposure device.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Patent Document 1 discloses a design in which the number of LEDs arranged in each of multiple circuits is the same. It also discloses a lens for focusing light from each LED. However, if there is insufficient space on the LED substrate, the number of LEDs in each of the multiple circuits may differ, which can be disadvantageous when controlling the LEDs. [Means for solving the problem]

[0006] A light source device as one aspect of the present invention comprises a plurality of LEDs arranged on a substrate and a plurality of lenses that focus the light from the plurality of LEDs, wherein the plurality of LEDs comprises a first LED group and a second LED group that are included in different circuits from each other, the number of LEDs included in the first LED group is the same as the number of LEDs included in the second LED group, and the first LED group is characterized in that at least one LED is arranged at a position away from the optical axis of the plurality of lenses. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a light source device that is advantageous for controlling LEDs. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic diagram showing the configuration of the exposure apparatus. [Figure 2] This is a schematic diagram showing the configuration of the illumination optical system. [Figure 3] This figure shows an optical cross-sectional view of a light source device. [Figure 4] This is a top view of the light source device. [Figure 5] This is a circuit diagram of an LED board. [Figure 6] This is a top view of an LED array light source. [Figure 7] This is a top view of the LED substrate with the fastening parts arranged. [Figure 8] This diagram shows a light source device with a cooling unit fixed to an LED substrate. [Figure 9] This is a top view of an LED array light source with fastening components arranged. [Figure 10] This is a diagram showing the light source device in the first embodiment. [Figure 11] This figure shows a light source device in a modified example of the first embodiment. [Figure 12] This figure shows the light source device in the second embodiment. [Figure 13] This figure shows a light source device in a modified example 1 of the second embodiment. [Figure 14] This figure shows the light source device in a modified example 2 of the second embodiment. [Figure 15] This figure shows the light source device in modified example 3 of the second embodiment. [Figure 16] This figure shows the light source device in a modified example 4 of the second embodiment. [Figure 17] This is a flowchart of the manufacturing method for an item. [Modes for carrying out the invention]

[0009] Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. In each drawing, the same reference numeral is used for identical components, and redundant descriptions are omitted.

[0010] <First Embodiment> Figure 1 shows the configuration of the illumination optical system of the exposure apparatus. The exposure apparatus 100 has an illumination optical system 8 that illuminates the mask 7 (original plate), which is the surface to be illuminated, with light, and a projection optical system 101 that projects an image of the pattern formed on the mask 7 onto a substrate 5 placed on the surface to be illuminated 4, which is at a position optically conjugate to the mask 7.

[0011] The projection optical system 101 illustrated in FIG. 1 is a reflective optical system that reflects light in the order of mirrors 1, 2, 3, 2, 1, and projects an image of the pattern of the mask 7 onto the substrate 5 disposed on the illuminated surface 4. The projection optical system 101 shown in FIG. 1 is a reflective optical system, an optical system in which chromatic aberration of light from a light source is smaller than that of a refractive optical system, and is suitable for broadband illumination. The substrate 5 is supported by a movable stage 6. The projection optical system 101 is not limited to a reflective optical system, and may be a reflective refractive optical system or a refractive optical system. Also, in FIG. 1, the projection optical system 101 is one projection optical system, but may be a multi-lens optical system in which a plurality of projection optical systems 101 are arranged, and the present invention can also be implemented individually for each projection optical system.

[0012] FIG. 2 is a diagram showing the configuration of the illumination optical system 8 surrounded by the light-shielding housing 9. The exposure apparatus according to the present embodiment includes a light source device 10 including an LED array light source 11 and a wavelength combining unit 16.

[0013] The LED array light source 11 is composed of, for example, two different LED array light sources 11a and 11b. The LED array light source 11a includes a plurality of first LED elements having a first wavelength characteristic λ1, and the LED array light source 11b includes a plurality of second LED elements having a second wavelength characteristic λ2 different from the first wavelength characteristic. The first LED element having the first wavelength characteristic λ1 is, for example, an LED element that emits light with a peak wavelength of 365 nm, and the second LED element having the second wavelength characteristic λ2 is, for example, an LED element that emits light with a peak wavelength of 405 nm.

[0014] Light having different wavelength characteristics emitted from each LED array light source is combined by the wavelength combining unit 16 and guided to the condenser lens 12. The wavelength combining unit 16 is, for example, a dichroic mirror, and is a glass substrate formed with an optical thin film that reflects a large amount of light having a wavelength of 365 nm and transmits a large amount of light having a wavelength of 405 nm.

[0015] Although the LED array light source 11a is described as an example in which an LED with a single wavelength of 365 nm is mounted, multiple LEDs with different emission wavelengths may be mixed in the LED array light source 11a as long as they have emission wavelengths that are reflected by the dichroic mirror. Similarly, for the LED array light source 11b, multiple LEDs with different emission wavelengths may be mixed in the LED array light source 11b as long as they have emission wavelengths that are transmitted through the dichroic mirror.

[0016] In terms of positional relationship, it is desirable to configure the system so that the emission surfaces of the LED array light sources 11a and 11b are located near the front focal position of the condenser lens 12, and the incident surface of the optical integrator 13 is located near the rear focal position of the condenser lens 12.

[0017] Here, the emission surfaces of the LED array light sources 11a and 11b and the incident surface of the optical integrator 13 do not need to perfectly coincide with the focal position of the condenser lens 12; for example, even if they are positioned at a point shifted by ±10% of the focal length, the effect will not be impaired.

[0018] The optical integrator 13 is, for example, a fly-eye lens and is composed of a large number of identical lens elements. The optical integrator 13 wavefront-splits the light on the incident surface and forms multiple light source images of the LED array light sources 11a and 11b at its exit surface. In other words, an optical image of the LED array light source 11 is formed on the exit surface of each of the many lens elements that make up the optical integrator 13, and this becomes a secondary light source.

[0019] The aperture diaphragm 14, positioned near the emission surface of the optical integrator 13, controls the angular distribution of light illuminating the mask 7. By providing, for example, an annular or quadrupole-shaped transmission region in the aperture diaphragm 14, it is possible to form deformed illumination such as annular or quadrupole.

[0020] Then, the second condenser lens 15 focuses the light that has passed through the aperture diaphragm 14 and illuminates the mask 7 with the resulting illumination light. The above describes an example in which a wavelength combining unit 16 using a dichroic mirror is configured. However, if a simpler configuration is desired, the wavelength combining unit 16 and the LED array light source 11a may be omitted.

[0021] In this case, a first LED element having the first wavelength characteristic λ1 and a first LED element having the second wavelength characteristic λ2 are mounted together on the LED array light source 11b. The light emitted from the LED array light source 11b is then directly focused by the condenser lens 12 and irradiated onto the optical integrator 13.

[0022] Next, the configuration of the LED array light source 11 will be explained in Figures 3 and 4.

[0023] The LED array light sources 11a and 11b can have the same configuration, except that their wavelength characteristics differ as described above.

[0024] Compared to high-pressure mercury lamps, LEDs have a smaller radiant flux per light source, making it practically essential to use multiple LEDs when using them as light sources in exposure equipment.

[0025] Figure 3 shows an LED array light source 11 with multiple LED elements 18 mounted on a substrate 17. Figure 4 is a top view of Figure 3, showing how the LED elements 18 are arranged two-dimensionally on the substrate 17.

[0026] The light emitted from an LED element has a very large angular distribution, for example, with a radiation angle of 60 to 70 degrees in half-angles, considering that the numerical aperture NA of a typical projection optical system for FPDs is around 0.1 (around 5.7 degrees). In order to capture the radiated light beam from the LED element without loss in the downstream optical system, a focusing lens 19 (multiple lenses) is provided directly above each LED element 18 (at the position corresponding to the LED) to make the radiated light beam approximately parallel (to focus the light from the LED).

[0027] Figure 4 shows the LED elements arranged in a square grid, but other arrangements, such as a staggered arrangement, are also possible. To optimize light utilization efficiency, it is desirable that the optical axis 20 of the focusing lens correspond to the center of each individual LED element 18. By configuring the light-emitting surface 21 of the LED element 18 to be located near the front focal position of the focusing lens 19, a distribution obtained by the Fourier transform of the light ray information on the light-emitting surface 21 of the LED element 18 is formed near the rear focal position of the focusing lens 19. If this rear focal position of the focusing lens 19 is configured to be located near the front focal position of the condenser lens 12, the light-emitting surface 21 of the LED element 18 and the incident surface of the optical integrator 13 become optically conjugate.

[0028] By configuring all LED elements 18 similarly, the light-emitting surfaces of all LED elements 18 and the incident surface of the optical integrator 13 become optically conjugate. In other words, the optical images of the light-emitting surfaces 21 of all LED elements 18 are superimposed and projected onto the incident surface of the optical integrator, forming a pupil intensity distribution.

[0029] In Figures 5, 6, 7, 8, and 9, for the sake of simplification, the explanation of the focusing lens 19, which is placed in pairs with each individual LED, will be omitted.

[0030] Figure 5 shows a top view of the LED board 22. This is an example in which multiple LED elements 18 are connected by wiring 23, and multiple series circuits 24, 25, and 26 are mounted. Power is supplied to the LED board 22 from the power supply 29 (voltage control unit) via connectors 27 and 28. Note that the maximum number of LEDs that can be mounted on a single board is limited due to manufacturing size constraints.

[0031] When using LED elements for exposure equipment, high illumination is required to improve the productivity of the equipment. Therefore, in order to achieve the necessary and sufficient illumination, it is necessary to arrange multiple LED substrates 22 at a high density to create a large area. Figure 6 shows an example of a large-area LED array light source 30.

[0032] Furthermore, the large-area LED array light source 30 needs to be driven with high power to produce high illumination, resulting in significant heat generation. Therefore, it is necessary to securely fix the LED substrate to a cooler for heat dissipation. Preferred methods for secure fixation include fastening with screws, bolts, or fixing plates. However, using fastening parts requires a considerable amount of space on the substrate surface.

[0033] From here on, we will explain using the case of fixing with screws as a representative example of fastening. Figure 7 shows a top view of the LED substrate 31 with screws 32, 33, 34, and 35 arranged therein. Figure 8 shows the LED substrate 31 fixed to the cooler 36 (cooling unit) using screws 32, 33, 34, and 35. The cooler 36 cools the substrate 31 from the back side (the side opposite to the side on which the LEDs are arranged). A known configuration for coolers is to dissipate heat by flowing a refrigerant controlled to a constant temperature by a chiller through a cooling channel 37.

[0034] Figure 9 is a top view of a large-area LED array light source 38, which consists of multiple LED substrates 31 fixed to a cooler with screws. The light-emitting area of ​​the large-area LED array light source 38, i.e., the area where the LED elements 18 are placed, must be located inside the effective light-emitting area 39 from which the exposure device can capture light. In this case, as shown in Figure 7, the areas around screws 34 and 35 cannot accommodate LED elements 18, and the number of LEDs in series circuits 24 and 26 decreases. In the example in Figure 7, circuits 24 and 26 have 11 LEDs, and series circuit 25 has 12 LEDs. Therefore, the required voltages for series circuits 24 and 26 and series circuit 25 will be different, which can complicate control.

[0035] Therefore, in this embodiment, as shown in Figure 10, the problem is solved by arranging at least one LED (LED 41, 42) at a position away from the optical axis of the focusing lens 19 (an LED that is not used as exposure light is deliberately placed). Figure 10 shows a substrate 40 as Example 1 in which LEDs 41 and 42 are arranged. In the following, LEDs 41 and 42 will also be called dummy LEDs. Of the series circuits 24, 25, and 26 of the substrate 40, dummy LEDs 41 and 42 are placed in series circuits 24 and 26 at a position away from the optical axis of the focusing lens 19. As a result, the number of LEDs in all series circuits becomes the same, and the required voltage is made uniform, which simplifies the power supply.

[0036] In this embodiment, a dummy LED is added to simplify the power supply, but since the number of components mounted on the board other than the LED element does not increase, it also has the effect of simplifying the process without increasing the number of mounting steps for other components.

[0037] In Figure 10, the circuit including the dummy LED 41 is also referred to as LED group 51 (first LED group), and the circuit not including the dummy LED is also referred to as LED group 52 (second LED group). In this embodiment, the number of LEDs included in LED group 51 is the same as the number of LEDs included in the second LED group. LED group 51 may have at least one LED positioned away from the optical axis of the focusing lens 19.

[0038] Furthermore, the distance between the LED group 51 and the screw 34 may be closer than the distance between the LED group 52 and the screw 34. The LED group 51 may be arranged so as not to overlap with the screw 34. This embodiment does not exclude the inclusion of dummy LEDs in the LED group 52, and such LEDs may be included. The number of LEDs in the LED group 52 that are positioned away from the optical axis of the focusing lens 19 should be less than the number of LEDs in the LED group 51 that are positioned at the optical axis of the corresponding lens of the focusing lens 19. More preferably, the number of LEDs in the LED group 52 that are positioned away from the optical axis of the focusing lens 19 may be 50% or less of the number of LEDs in the LED group 51 that are positioned at the optical axis of the corresponding lens of the focusing lens 19. For example, if the number of LEDs in the LED group 51 that are positioned at the optical axis of the corresponding lens of the focusing lens 19 is 4, the number of LEDs in the LED group 52 that are positioned away from the optical axis of the focusing lens 19 may be 2, 1, or 0.

[0039] In this embodiment, more preferably, in the LED group 51, at least one LED is positioned so as not to overlap with the condensing lens 19 in the direction of the optical axis of the condensing lens 19. This arrangement reduces the possibility that light from the LEDs may be included in the exposure light. In this embodiment, the LED group 51 may include at least one LED that emits less light reaching the master plate compared to the LEDs in the LED group 52.

[0040] As a modified example of this embodiment, Figure 11 shows a substrate 43 on which dummy LEDs are arranged. Of the series circuits 24, 25, and 26 of the substrate 43, dummy LEDs 41 and 42 are placed in series circuits 24 and 26 at positions away from the optical axis of the focusing lens 19. The focusing lens 19 may be an array in which each lens is integrated, but the focusing lens 19 and the dummy LEDs may be arranged so that they overlap in the direction of the optical axis, as long as they are at positions away from the optical axis of each lens of the focusing lens 19.

[0041] <Second Embodiment> In this embodiment, in addition to the configuration described in the first embodiment, we will describe how to perform abnormality detection of the light source device 10. The basic configuration of the light source device 10 is the same as in the first embodiment, so we will omit its description. Furthermore, matters not mentioned in this embodiment will follow those of the first embodiment.

[0042] Figure 12 illustrates a configuration for detecting abnormalities in the focusing lens 19 and the dichroic mirror 16 using two light intensity sensors (i.e., sensors 44a and 45, and a detection unit). Sensor 44a measures the amount of light 44b that passes through the focusing lens 19 and is not reflected by the dichroic mirror, after the light of wavelength λ1 emitted from the LED array light source 11a has passed through. On the other hand, sensor 45 measures the amount of light emitted from a dummy LED 41 of wavelength λ1 mounted on the LED array light source 11a that does not pass through either the focusing lens 19 or the dichroic mirror 16. If an abnormality such as clouding or misalignment occurs in the focusing lens 19 or the dichroic mirror 16, the ratio of the measured light intensity of sensors 44a and 45 changes, allowing for detection of the abnormality. Abnormality detection can be performed by a control unit 53, which is connected to each part of the light source device 10 and controls each part of the light source device 10.

[0043] The control unit 53 can detect an abnormality based on the amount of light from an LED located away from the optical axis of the condensing lens 19 in the first group of LEDs and the amount of light from an LED located at the optical axis of the corresponding lens in at least one of the plurality of LEDs arranged on the substrate. The abnormality may be information regarding clouding of an optical element through which the light from the LEDs passes. The optical element may be a dichroic mirror 16 or a condensing lens 19.

[0044] A modified example of this embodiment will be described with reference to Figure 13. Figure 13 shows an example where the dummy LED 41 with wavelength λ1 is positioned so that the light it emits passes through the focusing lens 19. Sensor 45 measures the amount of λ1 light that passes through the focusing lens 19 but not through the dichroic mirror 16. By monitoring the change in the ratio of the measured light amounts of sensor 44a and sensor 45, it is possible to detect abnormalities in only the dichroic mirror.

[0045] A modified example of this embodiment, Part 2, will be described with reference to Figure 14. Figure 14 shows an example in which a sensor 46a is added to Part 1, bringing the total number of sensors to three. Sensor 46a measures the light emitted from a dummy LED 41 with wavelength λ1 that has passed only through the dichroic mirror 16.

[0046] By monitoring the change in the light intensity ratio measured by sensors 46a and 45, it is possible to detect an abnormality in only the dichroic mirror 16. If there is an abnormality in the light intensity ratio measured by sensors 44a and 45, but there is no abnormality in sensors 45 and 46a, it can be determined that there is an abnormality in only the condensing lens 19.

[0047] A third modification of this embodiment will be described with reference to Figure 15. Figure 15 shows an example in which two types of dummy LEDs, a λ1 dummy LED 41 and a λ2 dummy LED 47, are arranged on a single substrate, and four sensors are used. Sensor 48 measures the light emitted from the λ2 dummy LED 47, and sensor 49 measures the light emitted from the λ2 dummy LED 47 that has passed through the dichroic mirror 16. By monitoring the changes in the measured light intensity of sensors 48 and 49, it is possible to detect abnormalities in only the dichroic mirror 16.

[0048] A modified example of this embodiment, part 4, will be described with reference to Figure 16. Figure 16 illustrates a configuration for detecting when the substrate λ1 and the substrate λ2 are incorrectly placed in reverse. Figure 16(a) shows the normal arrangement, and Figure 16(b) shows the case where the substrates are placed in reverse.

[0049] Because the dichroic mirror 16 reflects λ1 and transmits λ2, if the substrate arrangement is reversed, light will not reach the condenser lens 12, making exposure impossible. Sensor 45 is sensitive to λ1 and measures the light intensity of the dummy LED 41 at λ1. Sensor 50 is sensitive to λ2 and measures the light intensity of 11a and 11b. Compared to the normal light intensity measured by sensors 45 and 50, if the substrate is reversed, the light intensity λ1 measured by sensor 45 decreases and the light intensity λ2 measured by sensor 50 increases, allowing for the detection of an anomaly.

[0050] <Embodiment for manufacturing an article> The method for manufacturing articles according to the embodiment of the present invention is suitable for manufacturing articles such as flat panel displays (FPDs), semiconductor devices, sensors, and optical elements. Figure 17 is a flowchart of the method for manufacturing articles according to this embodiment. The method for manufacturing articles according to this embodiment includes a step of forming a latent image pattern on a photosensitive material coated on a substrate by exposure using the above-mentioned exposure apparatus 100 to obtain an exposed substrate (exposure step, step S11). It also includes a step of developing the substrate exposed in this step to obtain a developed substrate (development step, step S12). Furthermore, this manufacturing method includes other well-known steps (oxidation, film formation, vapor deposition, doping, planarization, etching, resist stripping, dicing, bonding, packaging, etc.) (processing step, step S13). The method for manufacturing articles according to this embodiment is advantageous compared to conventional methods in at least one of the performance, quality, productivity, and production cost of the articles.

[0051] Although 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 its gist. The scope to which the present invention is applicable may include, for example, light source devices used in semiconductor manufacturing equipment (film deposition equipment, sputtering equipment, annealing equipment, inspection equipment, etc.), organic EL deposition equipment, imprint equipment, planarization equipment, and other substrate processing equipment.

[0052] The disclosures herein include at least the following light source devices, exposure devices, and methods for manufacturing articles.

[0053] (Item 1) Multiple LEDs arranged on the circuit board, Multiple lenses that focus the light from the multiple LEDs, It has, The plurality of LEDs include a first group of LEDs and a second group of LEDs, which are included in different circuits from each other. The number of LEDs included in the first LED group is the same as the number of LEDs included in the second LED group. The first group of LEDs includes at least one LED positioned away from the optical axis of the plurality of lenses. A light source device characterized by the following features.

[0054] (Item 2) A cooling unit that cools the substrate from the back side, It further includes a fastening portion that fastens the cooling portion and the substrate together, The light source device according to item 1, characterized in that the distance between the first group of LEDs and the fastening portion is shorter than the distance between the second group of LEDs and the fastening portion.

[0055] (Item 3) The light source device according to item 2, characterized in that the first group of LEDs is arranged so as not to overlap the fastening portion.

[0056] (Item 4) The light source device according to any one of items 1 to 3, characterized in that the number of LEDs in the first LED group that are positioned away from the optical axis of the plurality of lenses is less than the number of LEDs in the first LED group that are positioned at the optical axis of the plurality of lenses.

[0057] (Item 5) The light source device according to item 4, characterized in that the number of LEDs in the first LED group that are positioned away from the optical axis of the plurality of lenses is 50% or less of the number of LEDs in the first LED group that are positioned at the optical axis of the plurality of lenses.

[0058] (Item 6) The light source device according to any one of items 1 to 5, characterized in that, in the first group of LEDs, at least one LED is arranged in a position that does not overlap with the optical axis direction of the plurality of lenses.

[0059] (Item 7) A detection unit for detecting light from the plurality of LEDs, The system further includes a control unit for detecting abnormalities in the light source device, The light source device according to any one of items 1 to 6, characterized in that the control unit detects the abnormality based on the amount of light from LEDs located away from the optical axis of the plurality of lenses in the first LED group and the amount of light from LEDs located at the optical axis of the plurality of lenses.

[0060] (Item 8) The light source device according to item 7, characterized in that the control unit is a member through which light from LEDs positioned away from the optical axis of the plurality of lenses in the first LED group does not pass, and detects an abnormality related to clouding of the optical member through which light from LEDs positioned at the optical axis of the plurality of lenses passes.

[0061] (Item 9) A light source device for illuminating a surface to be illuminated, Multiple LEDs arranged on the circuit board, Multiple lenses that focus the light from the multiple LEDs, It has, The plurality of LEDs include a first group of LEDs and a second group of LEDs, which are included in different circuits from each other. The number of LEDs included in the first LED group is the same as the number of LEDs included in the second LED group. The first group of LEDs includes at least one LED that emits less light reaching the illumination surface compared to the LEDs in the second group of LEDs. A light source device characterized by the following features.

[0062] (Item 10) An exposure apparatus characterized by illuminating a master plate with light from a light source device described in any one of items 1 to 9, and projecting an image of the pattern on the master plate onto a substrate.

[0063] (Item 11) An exposure step in which a substrate is exposed using the exposure apparatus described in item 10 to obtain an exposed substrate, The process includes developing the aforementioned photopolymer substrate to obtain a developed substrate, A method for manufacturing an article, characterized by manufacturing an article from the aforementioned developing substrate. [Explanation of Symbols]

[0064] 10 Light source device 19. Focusing lens (multiple lenses) 40 circuit boards 51 LED group (first LED group) 52 LED group (second LED group)

Claims

1. Multiple LEDs arranged on the circuit board, Multiple lenses that focus the light from the multiple LEDs, It has, The plurality of LEDs include a first group of LEDs and a second group of LEDs, which are included in different circuits from each other. The number of LEDs included in the first LED group is the same as the number of LEDs included in the second LED group. The first group of LEDs includes at least one LED positioned away from the optical axis of the plurality of lenses. A light source device characterized by the following features.

2. A cooling section for cooling the substrate is provided on the substrate from the side opposite to the side on which the plurality of LEDs are arranged. It further includes a fastening portion that fastens the cooling portion and the substrate together, The light source device according to claim 1, characterized in that the distance between the first group of LEDs and the fastening portion is shorter than the distance between the second group of LEDs and the fastening portion.

3. The light source device according to claim 2, characterized in that the first group of LEDs is arranged so as not to overlap the fastening portion.

4. The light source device according to claim 1, characterized in that the number of LEDs in the first LED group that are positioned away from the optical axis of the plurality of lenses is less than the number of LEDs in the first LED group that are positioned at the optical axis of the plurality of lenses.

5. The light source device according to claim 4, characterized in that the number of LEDs in the first LED group that are positioned away from the optical axis of the plurality of lenses is 50% or less of the number of LEDs in the first LED group that are positioned at the optical axis of the plurality of lenses.

6. The light source device according to claim 1, characterized in that, in the first group of LEDs, at least one LED is arranged in a position that does not overlap with the optical axis direction of the plurality of lenses.

7. A detection unit for detecting light from the plurality of LEDs, The system further includes a control unit for detecting abnormalities in the light source device, The light source device according to claim 1, characterized in that the control unit detects the abnormality based on the amount of light from LEDs in the first LED group that are located away from the optical axis of the plurality of lenses and the amount of light from LEDs that are located at the optical axis of the plurality of lenses.

8. The light source device according to claim 7, wherein the control unit is a member through which light from LEDs positioned away from the optical axis of the plurality of lenses in the first LED group does not pass, and detects an abnormality related to clouding of the optical member through which light from LEDs positioned at the optical axis of the plurality of lenses passes.

9. A light source device for illuminating a surface to be illuminated, Multiple LEDs arranged on the circuit board, Multiple lenses that focus the light from the multiple LEDs, It has, The plurality of LEDs include a first group of LEDs and a second group of LEDs, which are included in different circuits from each other. The number of LEDs included in the first LED group is the same as the number of LEDs included in the second LED group. The first group of LEDs includes at least one LED that emits less light reaching the illuminated surface compared to the LEDs in the second group of LEDs. A light source device characterized by the following features.

10. An exposure apparatus characterized by illuminating a master plate with light from a light source device according to any one of claims 1 to 9, and projecting an image of the pattern of the master plate onto a substrate.

11. An exposure step of exposing a substrate using the exposure apparatus described in claim 10 to obtain an exposed substrate, The process includes developing the aforementioned photopolymer substrate to obtain a developed substrate, A method for manufacturing an article, characterized by manufacturing an article from the aforementioned developing substrate.

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