An illumination system and a lithographic apparatus

Abstract

This application discloses an illumination system and a lithography machine, relating to the field of semiconductor equipment technology. The illumination system includes a light source module and a light-diffusing module, a slit plate, and a relay module sequentially disposed on the light-emitting side of the light source module. Light emitted from the light source module passes sequentially through the light-diffusing module, a slit on the slit plate, and the relay module before illuminating the target surface. The light-diffusing module includes a first light-diffusing rod, a scattering element, and a second light-diffusing rod arranged at intervals along the optical path. The light emitted from the light source module undergoes light-diffusing by the first light-diffusing rod, scattering by the scattering element, and light-diffusing by the second light-diffusing rod. The relay module is used to increase the illumination field of view. The illumination system and lithography machine provided by this application can improve the uniformity of illumination while reducing the overall size of the illumination system.

Description

Technical Field

[0001] This application relates to the field of semiconductor equipment technology, and more specifically, to a lighting system and a lithography machine. Background Technology

[0002] In a photolithography machine, the illumination system adjusts the incident light from the light source (laser or mercury lamp) to provide a high-quality illumination field for the mask, thereby ensuring the image quality of the mask pattern projected onto the silicon wafer through the projection lens. Among the various indicators for measuring the quality of the illumination field, illumination uniformity is a crucial one, directly affecting the final pattern quality projected onto the silicon wafer through the projection lens. Generally, photolithography machines require the non-uniformity of the illumination field to be less than 1%. Since the incident light from the light source (laser or mercury lamp) inherently has non-uniformity, this places extremely high demands on the uniformity performance of the illumination system.

[0003] Because light rays from different illumination spots pass through different lenses during propagation, the absorption of light from different fields of view varies. Furthermore, in real lithography exposure systems, it is difficult to control the coating uniformity on lenses with steep surface angles, which also leads to differences in light intensity between different illumination spots. Therefore, it is essential to fully calibrate the illumination uniformity of the lithography exposure system to meet the operational requirements of the lithography machine.

[0004] In existing technologies, a light-diffusing rod is usually used to homogenize the light and achieve a uniform light effect. It uses multiple reflections within the cavity to mix the incident light distribution and produce a uniform light effect. The more reflections, the better the uniform light effect. The simplest way is to increase the length of the light-diffusing rod to increase the number of reflections. However, simply increasing the number of reflections will make the entire lighting system too long and bulky, which is not conducive to assembly. Summary of the Invention

[0005] The purpose of this application is to provide a lighting system and a lithography machine that can improve the uniformity of lighting while reducing the size of the lighting system.

[0006] One embodiment of this application provides a lighting system, including a light source module and a light-diffusing module, a slit plate, and a relay module sequentially disposed on the light-emitting side of the light source module. The light emitted from the light source module passes sequentially through the light-diffusing module, the slit on the slit plate, and the relay module before illuminating the target surface. The light-diffusing module includes a first light-diffusing rod, a scattering element, and a second light-diffusing rod arranged sequentially at intervals along the light path. The light emitted from the light source module passes sequentially through the light-diffusing effect of the first light-diffusing rod, the scattering effect of the scattering element, and the light-diffusing effect of the second light-diffusing rod. The relay module is used to increase the illumination field of view of the light.

[0007] As one feasible approach, the relay module includes a field-enlarging lens group and an adjustment lens group arranged sequentially along the optical path direction. The adjustment lens group moves along the optical axis to adjust the field of view of the illumination system.

[0008] As one feasible approach, the field-enlarging lens group includes a first sub-lens group, a variable aperture, and a second sub-lens group arranged sequentially along the optical path.

[0009] As one possible approach, the adjustment lens assembly includes a concave-convex lens, with the concave surface of the lens facing the target surface.

[0010] As an feasible approach, a light-emitting component is also provided on the light-emitting side of the adjusting lens assembly, and the light-emitting component can be moved in a direction perpendicular to the optical axis.

[0011] As an feasible approach, relay modules increase the field of view by 3-5 times.

[0012] As an feasible approach, the numerical aperture of the variable aperture is between 0.1 and 0.15.

[0013] As one feasible approach, the scattering element is a diffuser, and the distance between the first and second diffusers is less than 5 mm.

[0014] As one feasible approach, the scattering element is a microlens array, and the distance between the first and second homogenizing rods is between 4 and 8 mm.

[0015] Another embodiment of this application provides a lithography machine, including the above-mentioned illumination system and a projection lens disposed on the light-emitting side of the illumination system. A photomask is disposed between the illumination system and the projection lens. The light spot formed by the illumination system illuminates the photomask, and the pattern on the photomask is projected onto the product to be lithographically lithographically imaged by the projection lens.

[0016] The beneficial effects of the embodiments of this application include:

[0017] The lighting system provided in this application includes a light source module and a light-diffusing module, a slit plate, and a relay module sequentially arranged on the light-emitting side of the light source module. Light emitted from the light source module passes sequentially through the light-diffusing module, the slit on the slit plate, and the relay module before illuminating the target surface. The relay module is used to increase the illumination field of view. The light-diffusing module includes a first light-diffusing rod, a scattering element, and a second light-diffusing rod arranged at intervals along the light path. Light emitted from the light source module passes sequentially through the light-diffusing rod, the scattering element, and the second light-diffusing rod. The light diffused by the first light-diffusing rod enters the scattering element, which changes the propagation path of the light, causing the light to disperse and thus rearrange its direction for secondary light-diffusing. The rearranged light enters the second light-diffusing rod, which performs a third light-diffusing. The light-diffusing effect of the second light-diffusing rod is the same as that of the first light-diffusing rod, and can be referenced. Figure 3 The light undergoes three homogenization processes—the first homogenizing rod, the scattering element, and the second homogenizing rod—resulting in a highly effective homogenizing module according to this application. Furthermore, this application achieves homogenization through two homogenizing rods and the scattering element, reducing the size of the homogenizing module compared to using only homogenizing rods. Therefore, this application can improve the homogenizing effect of the homogenizing module without increasing its overall size. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the structure of a lighting system provided in an embodiment of this application;

[0020] Figure 2 This is a schematic diagram of the structure of the light-diffusing module provided in the embodiments of this application;

[0021] Figure 3 This is a schematic diagram of the light-uniforming effect of the first light-uniforming rod provided in an embodiment of this application;

[0022] Figure 4 This is a schematic diagram of the structure of a relay module provided in an embodiment of this application;

[0023] Figure 5 The relative illumination map is provided for the relay module in the embodiments of this application.

[0024] Icons: 100 - Illumination system; 110 - Light source module; 120 - Light homogenizing module; 121 - First light homogenizer; 122 - Diffusing element; 123 - Second light homogenizer; 130 - Slit plate; 140 - Relay module; 141 - Field-of-view magnifying lens group; 142 - Adjustment lens group; 143 - First sub-lens group; 144 - Variable aperture; 145 - Second sub-lens group; 146 - Astigmatism assembly; 151 - Light source element; 152 - Shutter; 153 - First filter; 160 - Light source zoom assembly; 170 - Second filter; 181 - First reflecting mirror; 182 - Second reflecting mirror. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0027] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0028] An illumination system, used in a lithography machine, provides an illumination field with a specific spectral and intensity distribution for the machine's projection lens. Specifically, the lithography machine includes an illumination system and a projection lens positioned on the light-emitting side of the illumination system. A photomask is placed between the illumination system and the projection lens, and the product to be lithographically etched is placed on the light-emitting side of the projection lens. Specifically, the illumination system provides an illumination field that passes through the photomask, allowing a portion of the illumination field to pass through the transparent area on the photomask. The transmitted illumination field then passes through the projection lens, which compensates for optical errors and proportionally reduces the circuit pattern on the photomask before mapping it onto the product to be lithographically etched. As can be seen from the above, the uniformity of the illumination field provided by the illumination system directly affects the lithography accuracy. To improve the uniformity of the illumination system, this application provides an illumination system.

[0029] This application provides a lighting system 100, such as... Figure 1 and Figure 2As shown, the system includes a light source module 110 and a light-diffusing module 120, a slit plate 130, and a relay module 140 sequentially disposed on the light-emitting side of the light source module 110. The light emitted from the light source module 110 passes sequentially through the light-diffusing module 120, the slit on the slit plate 130, and the relay module 140 before illuminating the target surface. The light-diffusing module 120 includes a first light-diffusing rod 121, a scattering element 122, and a second light-diffusing rod 123 arranged sequentially at intervals along the light path. The light emitted from the light source module 110 passes sequentially through the light-diffusing effect of the first light-diffusing rod 121, the scattering effect of the scattering element 122, and the light-diffusing effect of the second light-diffusing rod 123. The relay module 140 is used to increase the illumination field of view of the light.

[0030] The illumination system 100 provided in this application embodiment can provide a uniform illumination field for the projection lens. Specifically, the illumination system 100 in this application embodiment includes a light source module 110 and a light-uniforming module 120, a slit plate 130, and a relay module 140 sequentially disposed on the light-emitting side of the light source module 110. The light-uniforming module 120 is used to uniformly distribute the illumination light in the illumination field. The slit plate 130 is used to control the direction and intensity of the light irradiated to the relay module 140. The relay module 140 is used to increase the illumination field of view of the light and can adjust the illumination field of view according to the size of the mask to adapt to masks of different sizes.

[0031] Specifically, in order to improve the uniformity of the illumination light field of the lighting system 100 of this application, the embodiment of this application sets the light-diffusing module 120 as a first light-diffusing rod 121, a scattering element 122, and a second light-diffusing rod 123 arranged sequentially at intervals along the optical path, such as... Figure 2 As shown, the light emitted from the light source module 110 first passes through the first light-diffusing rod 121 for light homogenization. Specifically, the light homogenization effect of the first light-diffusing rod 121 is as follows: Figure 3 As shown, light rays homogenized by the first homogenizing rod 121 are incident on the scattering element 122. The scattering element 122 changes the propagation path of the light rays, causing them to disperse and thus rearrange their directions, performing a second homogenization. The rearranged light rays are then incident on the second homogenizing rod 123, which performs a third homogenization. The homogenizing effect of the second homogenizing rod 123 is the same as that of the first homogenizing rod 121, and can be referenced. Figure 3 The light is homogenized three times by the first homogenizing rod 121, the scattering element 122, and the second homogenizing rod 123, which makes the homogenizing module 120 of this embodiment have a very good homogenizing effect.

[0032] The homogenizing principle of the light-diffusing rod is based on the fact that as light propagates within the rod, it undergoes multiple reflections on its surface. These reflections mix the light distribution, resulting in a homogenized effect. Specifically, each reflection divides a portion of the light into virtual sub-point sources, and the angle of the light is divided into multiple sub-angle channels. Each virtual sub-point source corresponds to a sub-angle channel. After each reflection, the originally freely propagating distribution of the corresponding passband is reversed once. Finally, the distributions of multiple sub-angle channels superimpose at the light-emitting surface of the light-diffusing rod to form a uniform illuminance distribution. Based on this homogenizing principle, the more reflections, the better the homogenizing effect. According to the law of reflection, the distance that a single reflection needs to travel within the light-diffusing rod is constant. When more reflections are required, a longer light-diffusing rod is needed, resulting in a longer length for the light-diffusing module 120 and thus a larger volume. In order to avoid increasing the volume of the light-diffusing module 120, this embodiment of the application provides a first light-diffusing rod 121, a scattering element 122, and a second light-diffusing rod 123 in the light-diffusing module 120. Due to the light-diffusing effect of the scattering element 122, the light-diffusing effect can be improved without increasing the volume of the light-diffusing module 120.

[0033] In summary, the embodiments of this application can improve the light uniformity effect of the light uniformity module 120 without increasing the volume of the light uniformity module 120.

[0034] In practical applications, such as Figure 1 As shown, the light source module 110 includes a light-emitting element 151, a first filter 153, a shutter 152, and a light source zoom assembly 160 sequentially disposed on the light-emitting side of the light-emitting element 151. The light source zoom assembly includes a second filter 170 to process the light beam emitted from the light-emitting element 151, filtering out unwanted spectral components or interfering components in the background, and zooming the light beam. The specific structure of the light source module 110 described above is one example; those skilled in the art can customize the light source module 110 according to actual conditions, as long as it can emit relatively pure light.

[0035] In addition, to reduce the volume of the lighting system 100 in a specific direction, it can be done as follows: Figure 1 As shown, reflectors are respectively installed between the light source module 110 and the light-diffusing module 120, and between the relay module 140 and the mask plate, as shown. Figure 1 As shown, there are two reflectors, namely the first reflector 181 and the second reflector 182. Two reflectors are set in the optical path. After the light is reflected by the two reflectors, the path of the light is folded, thereby reducing the volume of the lighting system 100.

[0036] The lighting system 100 provided in this application includes a light source module 110 and a light-diffusing module 120, a slit plate 130 and a relay module 140 sequentially disposed on the light-emitting side of the light source module 110. The light emitted from the light source module 110 passes through the light-diffusing module 120, the slit on the slit plate 130 and the relay module 140 in sequence before illuminating the target surface. The relay module 140 is used to increase the illumination field of view of the light. The light-uniform module 120 includes a first light-uniforming rod 121, a scattering element 122, and a second light-uniforming rod 123 arranged sequentially along the optical path. Light emitted from the light source module 110 passes through the first light-uniforming rod 121 for homogenization, the scattering element 122 for scattering, and the second light-uniforming rod 123 for homogenization. The light homogenized by the first light-uniforming rod 121 then enters the scattering element 122, which changes the propagation path of the light, causing the light to disperse and thus rearrange its direction for secondary homogenization. The rearranged light then enters the second light-uniforming rod 123, which performs a third homogenization. The homogenization effect of the second light-uniforming rod 123 is the same as that of the first light-uniforming rod 121. Figure 3 The light is homogenized three times by the first homogenizing rod 121, the scattering element 122, and the second homogenizing rod 123, resulting in a good homogenizing effect for the homogenizing module 120 in this embodiment. Furthermore, this application achieves homogenization through two homogenizing rods and the scattering element 122, which reduces the size of the homogenizing module compared to using only homogenizing rods. Therefore, this embodiment can improve the homogenizing effect of the homogenizing module 120 without increasing its size.

[0037] Optional, such as Figure 4 As shown, the relay module 140 includes a field-enlarging lens group 141 and an adjustment lens group 142 arranged sequentially along the optical path direction. The adjustment lens group 142 moves along the optical axis direction to adjust the field size of the illumination system 100.

[0038] With the continuous development of semiconductor technology, the size of the product to be lithographicated also changes, and similarly, the size of the photomask also changes. In this embodiment, the adjustment mirror group 142 of the relay module 140 can adjust the size of the illumination field of view. The field-of-view enlarging mirror group 141 is used to increase the illumination field of view of the light, allowing the light to illuminate a larger area. The adjustment mirror group 142 adjusts the illumination field of view according to the size of the photomask to adapt to photomasks of different sizes. Specifically, the adjustment mirror group 142 can move along the optical axis to adaptively adjust the increased field of view, making the size of the field of view adaptable to photomasks of different sizes.

[0039] In one possible implementation of the embodiments of this application, such as Figure 4As shown, the field-enlarging lens group 141 includes a first sub-lens group 143, a variable aperture 144, and a second sub-lens group 145 arranged sequentially along the optical path.

[0040] Specifically, such as Figure 4 As shown, the first sub-lens group 143 includes a first lens, a second lens, a third lens, a fourth lens and a fifth lens arranged sequentially along the optical axis. The first lens, the second lens and the third lens are all concave-convex lenses with their convex surfaces facing the adjustment lens group 142. The fourth lens is a biconvex lens and the fifth lens is a concave-convex lens with its concave surface facing the adjustment lens group 142.

[0041] The numerical aperture of the variable aperture 144 is adjustable to adjust the numerical aperture of the illumination system 100 so that the illumination system 100 matches the projection lens.

[0042] The second sub-lens group 145 includes a sixth lens, a seventh lens, an eighth lens, a ninth lens, and a tenth lens arranged sequentially along the optical axis. The sixth and eighth lenses are plano-convex lenses, the seventh lens is a biconvex lens, and the convex surfaces of the sixth and eighth lenses face the seventh lens. The ninth and tenth lenses are both concave-convex lenses, with the concave surface of the ninth lens facing the variable aperture 144 and the concave surface of the tenth lens facing the adjustment lens group 142.

[0043] By positioning the ten lenses and the variable aperture 144, the field-of-view magnifying lens group 141 can expand the field of view of the beam.

[0044] Optional, such as Figure 4 As shown, the adjustment lens assembly 142 includes a concave-convex lens, with the concave surface of the lens facing the target surface.

[0045] Concave and convex lenses have the function of converging light rays. When they move along the optical axis, the field of view of the received light beams is different, thus converging light beams with different field of view and emitting light beams with different field of view, thereby achieving the function of adjusting the field of view.

[0046] Specifically, such as Figure 4 As shown, the two sides of the concave-convex lens along the optical axis are a concave surface and a convex surface, respectively, with the convex surface facing the target surface.

[0047] In one possible implementation of the embodiments of this application, such as Figure 4 As shown, a light-emitting component 146 is also provided on the light-emitting side of the adjusting lens assembly 142. The light-emitting component 146 is movable in a direction perpendicular to the optical axis. The light-emitting component 146 is used to further homogenize the light beam to further improve the uniformity of the light beam.

[0048] Furthermore, when the aforementioned adjusting lens assembly 142 is adjusted back and forth along the optical axis, the beam emitted from the relay module 140 is adjusted in the vertical direction. To better homogenize the beam, the astigmatism component 146 is configured to be movable in a direction perpendicular to the optical axis. In practical applications, a mask can be placed at the position of the astigmatism component 146, and the mask can be moved in the vertical direction.

[0049] To facilitate understanding of the relay module 140 in this embodiment, the parameters and positional relationships of each lens in the relay module 140 are summarized in Table 1 along the object side to the image side. The radius column refers to the radius of curvature of each lens end face. The first row represents the radius of curvature of the end face closer to the object side, and the second row represents the radius of curvature of the end face closer to the image side. A positive value in the radius of curvature indicates that the center of curvature of the lens end face is on the side closer to the image side, while a negative value indicates that the center of curvature of the lens end face is on the side closer to the object side. "infinity" indicates that this surface is a plane. The thickness column refers to the thickness or gap of each lens along the object side to the image side. The gap refers to the interval between each lens, and the filling gas is air. The thickness refers to the thickness along the principal optical axis.

[0050] Table 1 Parameter table of relay module 140

[0051]

[0052]

[0053] The relay module 140 is used to provide a uniformly distributed illumination field for the projection lens. To verify the homogenization effect of the relay module on the light, the relative illuminance map of the relay module 140 is measured. Figure 5 This is the relative illumination curve for relay module 140, where the horizontal axis represents the field of view size and the vertical axis represents the normalized relative illumination value. Figure 5 It can be seen that the relative illumination of the relay module 140 is relatively uniform. It should be noted that the relay module 140 in this embodiment is centrally symmetrically arranged, and the horizontal axis represents the distance from the edge of the field of view center.

[0054] In practical applications, the eleventh and twelfth lenses in Table 1 can be used as astigmatic elements. Figure 4 The two relatively close lenses located behind the adjusting lens group 142 are the eleventh lens and the twelfth lens, respectively, and the last element is the upper surface of the mask.

[0055] Optional, such as Figure 4 As shown, the relay module 140 increases the field of view by 3-5 times.

[0056] In the process of increasing the field of view, multiple lenses need to adjust the quality of the beam while increasing the field of view. A balance needs to be struck between beam quality and field of view increase. In this embodiment, the relay module 140 increases the field of view by 3-5 times.

[0057] Specifically, the lighting system 100 of this application embodiment has a maximum field of view of 135mm*115mm, which can be matched with a 6-inch photomask.

[0058] In one possible implementation of this application embodiment, the numerical aperture of the variable aperture 144 is between 0.1 and 0.15.

[0059] Optionally, the scattering element 122 is a diffuser, and the distance between the first light-diffusing rod 121 and the second light-diffusing rod 123 is less than 5 mm.

[0060] When the scattering element 122 is a diffuser, the diffuser is inserted between the first light-diffusing rod 121 and the second light-diffusing rod 123. According to the diffuser's scattering principle, in order to avoid a large distance between the diffuser and the first light-diffusing rod 121 and the second light-diffusing rod 123, which would cause some light beams to leak during scattering and waste light, the distance between the first light-diffusing rod 121 and the second light-diffusing rod 123 is set to be small in this embodiment. Specifically, the distance between the first light-diffusing rod 121 and the second light-diffusing rod 123 is less than 5mm, for example, it can be 4.5mm or 4mm.

[0061] It is understood that the distance between the first homogenizing rod 121 and the second homogenizing rod 123 refers to the distance between the sides of the first homogenizing rod 121 and the second homogenizing rod 123 that are close to each other. In addition, the diffuser is inserted between the first homogenizing rod 121 and the second homogenizing rod 123, and the distance between the first homogenizing rod 121 and the second homogenizing rod 123 should be at least greater than the thickness of the diffuser.

[0062] In one possible implementation of this application embodiment, the scattering element 122 is a microlens array, and the distance between the first light-diffusing rod 121 and the second light-diffusing rod 123 is between 4-8 mm.

[0063] The surface of the microlens array has multiple microstructures, which scatter light to achieve the purpose of scattering the light beam. In addition, since the microlens array has a certain converging effect during the scattering process, when the scattering element 122 is a microlens array, the distance between the first light-diffusing rod 121 and the second light-diffusing rod 123 can be set to be slightly larger. For example, it can be set between 4-8 mm, preferably between 4-5 mm, and specifically, it can be 4 mm, 4.5 mm, 5 mm, etc.

[0064] It should be noted that the above-described astigmatic elements are illustrated using microlens arrays and astigmatism plates as examples, but this should not be considered a limitation on the scattering element 122. Specifically, the structure of the astigmatic element is not limited in this embodiment. For example, it can be a surface astigmatic element or a volume astigmatic element. The surface astigmatic element has regular or irregular microstructures on its surface to scatter the light beam in different directions; the volume astigmatic element contains particles, bubbles, or other components inside, which scatter the light during its propagation.

[0065] This application also discloses a lithography machine, including the aforementioned illumination system 100 and a projection lens disposed on the light-emitting side of the illumination system 100. A photomask is disposed between the illumination system 100 and the projection lens. The light spot formed by the illumination system 100 illuminates the photomask, and the pattern on the photomask is projected onto the product to be lithographically lithographically imaged by the projection lens. This lithography machine has the same structure and beneficial effects as the illumination system 100 in the foregoing embodiments. The structure and beneficial effects of the illumination system 100 have been described in detail in the foregoing embodiments and will not be repeated here.

[0066] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A lighting system, characterized by The illumination system comprises a light source module, a uniform light module, a slit plate and a relay module arranged in sequence on the light exit side of the light source module, the light emitted by the light source module passes through the uniform light module, the slit on the slit plate and the relay module in sequence and then irradiates onto a target surface, wherein the uniform light module comprises a first uniform light rod, a scattering element and a second uniform light rod arranged in sequence along the light path, the light emitted by the light source module passes through the uniform light of the first uniform light rod, the scattering of the scattering element and the uniform light of the second uniform light rod in sequence, and the relay module is used to increase the illumination field of view of the light. The scattering element is a diffuser, and the distance between the first uniform light rod and the second uniform light rod is less than 5 mm.

2. The lighting system of claim 1, characterized in that The relay module comprises a field of view increasing lens group and an adjusting lens group arranged in sequence along the light path direction, and the adjusting lens group moves along the optical axis direction to adjust the field of view size of the illumination system.

3. The lighting system of claim 2, wherein, The field of view increasing lens group comprises a first sub-lens group, a variable diaphragm and a second sub-lens group arranged in sequence along the light path direction.

4. The lighting system of claim 2, wherein, The adjusting lens group comprises a meniscus lens, and the concave surface of the meniscus lens faces the target surface.

5. The lighting system of claim 2, wherein, The light exit side of the adjusting lens group is further provided with a diffusing assembly, and the diffusing assembly is movable along the direction perpendicular to the optical axis.

6. The lighting system of claim 2, wherein, The relay module increases the field of view by 3-5 times.

7. The lighting system of claim 3, wherein, The numerical aperture of the variable diaphragm is between 0.1 and 0.

15.

8. The lighting system of claim 1, wherein, The scattering element is a microlens array, and the distance between the first uniform light rod and the second uniform light rod is between 4 and 8 mm.

9. A lithographic machine characterized by, The illumination system comprises a light source module, a uniform light module, a slit plate and a relay module arranged in sequence on the light exit side of the light source module, the light emitted by the light source module passes through the uniform light module, the slit on the slit plate and the relay module in sequence and then irradiates onto a target surface, wherein the uniform light module comprises a first uniform light rod, a scattering element and a second uniform light rod arranged in sequence along the light path, the light emitted by the light source module passes through the uniform light of the first uniform light rod, the scattering of the scattering element and the uniform light of the second uniform light rod in sequence, and the relay module is used to increase the illumination field of view of the light.

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