Light filtering structure and method of manufacturing, imaging system and imaging method

Abstract

The application discloses a filter structure and a manufacturing method thereof, an imaging system and an imaging method. The filter structure comprises a zirconium film, an intermediate layer film and an aluminum film which are sequentially stacked from bottom to top; the intermediate layer film comprises a molybdenum film, a niobium film or a zirconium nitride film. The manufacturing method of the filter structure comprises the following steps: providing a zirconium film with a first preset thickness; plating an intermediate layer film with a second preset thickness on the zirconium film, the intermediate layer film comprising a molybdenum film, a niobium film or a zirconium nitride film; and plating an aluminum film with a third preset thickness on the intermediate layer film to obtain the filter structure. The filter structure provided by the embodiment of the application comprises a zirconium film, an intermediate layer film and an aluminum film which are sequentially stacked from bottom to top, can filter out stray light to a great extent, greatly eliminates the influence of stray light, thereby improving the imaging quality of extreme ultraviolet imaging, and solves the technical problems of poor filtering effect of stray light, great influence of stray light and low imaging quality of an extreme ultraviolet imaging system in the related art.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of photolithography, and particularly relates to a light filtering structure and a manufacturing method thereof, an imaging system and an imaging method. BACKGROUND

[0002] The photolithography process is a main process in the production process of semiconductor integrated circuits. With the continuous development of photolithography technology, the extreme ultraviolet lithography (EUVL, Extreme Ultraviolet Lithography) technology with a wavelength of 13.5 nm has become a mainstream photolithography technology for nodes below 7 nm, and has been widely used in the technical field. In the related art, in addition to the extreme ultraviolet light component, there is also a stray light component of other wavebands in the light source used in the photolithography process, which greatly affects the imaging quality. In the related art, the filtering effect of the stray light is not good, and the influence of the stray light is large, resulting in low imaging quality of the extreme ultraviolet imaging system, which is a technical problem to be solved. SUMMARY

[0003] The purpose of the present application is to provide a light filtering structure and a manufacturing method thereof, an imaging system and an imaging method, to solve the technical problem of low imaging quality of the extreme ultraviolet imaging system caused by the poor filtering effect of the stray light and the large influence of the stray light in the related art. In order to have a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. This part is not a general review, nor is it intended to determine the key / important components or delineate the protection scope of these embodiments. Its only purpose is to present some concepts in a simple form as a prelude to the detailed description that follows.

[0004] According to an aspect of an embodiment of the present application, a light filtering structure is provided, comprising a zirconium film, an intermediate layer film and an aluminum film stacked in sequence from bottom to top; the intermediate layer film comprises a molybdenum film, a niobium film or a zirconium nitride film.

[0005] In some embodiments of the present application, the thickness of the zirconium film is 50-200 nm, the thickness of the intermediate layer film is 30-100 nm, and the thickness of the aluminum film is 30-150 nm.

[0006] In some embodiments of the present application, the thickness of the zirconium film is 100 nm, the thickness of the intermediate layer film is 50 nm, and the thickness of the aluminum film is 100 nm.

[0007] In some embodiments of the present application, the thickness of the zirconium film is 50 nm, the thickness of the intermediate layer film is 30 nm, and the thickness of the aluminum film is 30 nm.

[0008] In some embodiments of the present application, the thickness of the zirconium film is 200 nm, the thickness of the intermediate layer film is 100 nm, and the thickness of the aluminum film is 150 nm.

[0009] According to another aspect of embodiments of the present application, a method for manufacturing a filter structure is provided, comprising:

[0010] providing a zirconium film with a first preset thickness;

[0011] depositing an intermediate layer film with a second preset thickness on the zirconium film, the intermediate layer film comprising a molybdenum film, a niobium film, or a zirconium nitride film;

[0012] depositing an aluminum film with a third preset thickness on the intermediate layer film to obtain the filter structure.

[0013] In some embodiments of the present application, the depositing an intermediate layer film with a second preset thickness on the zirconium film comprises:

[0014] depositing a molybdenum film with a fourth preset thickness on the zirconium film;

[0015] depositing a niobium film with a fifth preset thickness on the surface of the molybdenum film;

[0016] depositing a zirconium nitride film with a sixth preset thickness on the niobium film to complete the film deposition operation of the intermediate layer film;

[0017] wherein the sum of the fourth preset thickness, the fifth preset thickness, and the sixth preset thickness is equal to the second preset thickness.

[0018] According to another aspect of embodiments of the present application, an extreme ultraviolet indirect imaging system is provided, comprising a scintillator, the filter structure described above, a coupling system, and a visible light sensor; the filter structure is disposed on the scintillator; the scintillator is configured to convert extreme ultraviolet light that has passed through the filter structure into visible light, and the coupling system is configured to couple the visible light to the visible light sensor to form an image.

[0019] According to another aspect of embodiments of the present application, an extreme ultraviolet indirect imaging method is provided, which is implemented by the extreme ultraviolet indirect imaging system described above; the method comprises:

[0020] extreme ultraviolet light passes through the filter structure to obtain filtered light;

[0021] the scintillator converts the filtered light into visible light;

[0022] the coupling system couples the visible light to the visible light sensor to form an image.

[0023] In some embodiments of the present application, the extreme ultraviolet light passes through the light filtering structure to obtain filtered light, including: the extreme ultraviolet light sequentially passes through the zirconium film, the intermediate layer film and the aluminum film to obtain the filtered light.

[0024] The technical scheme provided in one of the aspects of the embodiments of the present application can include the following beneficial effects:

[0025] The light filtering structure provided by the embodiments of the present application includes a zirconium film, an intermediate layer film and an aluminum film which are stacked in turn from bottom to top, and the intermediate layer film includes a molybdenum film, a niobium film or a zirconium nitride film, which can filter out stray light to a great extent, greatly eliminating the influence of stray light, thereby improving the imaging quality of extreme ultraviolet imaging, and solving the technical problems of poor filtering effect of stray light, great influence of stray light and low imaging quality of the extreme ultraviolet imaging system in the related art.

[0026] Other features and advantages of the present application will be described in the following description, and some of them will become apparent from the description, or can be learned or determined without any doubt from the description, or can be understood by implementing the embodiments of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical schemes in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments described in the present application, and those skilled in the art can obtain other drawings according to these drawings without any creative labor.

[0028] Figure 1 Structure diagram of an extreme ultraviolet indirect imaging detector system.

[0029] Figure 2 Principle diagram of an extreme ultraviolet light imaging system.

[0030] Figure 3 Reflectivity spectrum distribution diagram of a 40-period Mo / Si multilayer film structure mirror.

[0031] Figure 4 Transmittance spectrum distribution diagram of a 100nm-thick Zr film.

[0032] Figure 5 Transmittance spectrum distribution diagram of a Zr film and a 100nm Al film structure (total thickness of 100nm).

[0033] Figure 6 Longitudinal sectional structure schematic diagram of the light filtering structure provided by one of the embodiments of the present application.

[0034] Figure 7 The transmittance spectral distribution diagram of the Zr film + 50 nm Mo film + 100 nm Al film structure (total thickness of 100 nm).

[0035] Figure 8 The transmittance spectral distribution diagram of the Zr film + 50 nm Nb film and 100 nm Al film structure (total thickness of 100 nm).

[0036] Figure 9 The transmittance spectral distribution diagram of the Zr film + 50 nm ZrN film + 100 nm Al film structure (total thickness of 100 nm).

[0037] Figure 10 An extreme ultraviolet indirect imaging system structure block diagram provided by another embodiment of the present application is shown.

[0038] Figure 11 An extreme ultraviolet indirect imaging method flow chart provided by another embodiment of the present application is shown.

[0039] The implementation, functional features and advantages of the present application will be further described with reference to the accompanying drawings in conjunction with the embodiments. DETAILED DESCRIPTION

[0040] In order to make the purposes, technical solutions and advantages of the present application more clear, the present application will be further described below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, and are not used to limit the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts, fall within the scope of protection of the present application.

[0041] Those skilled in the art can understand that, unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meaning as commonly understood by those skilled in the art in the field of the present application. It should also be understood that terms such as those defined in a general dictionary should be understood to have meanings consistent with meanings in the context of the prior art, and should not be interpreted to have idealized or overly formal meanings unless specifically defined as such herein.

[0042] In the related art, extreme ultraviolet light sources mainly include four types, which are: DPP (Discharged Produced Plasma) extreme ultraviolet light source, LPP (Laser Produced Plasma) extreme ultraviolet light source, LDP (Laser-assisted Discharge Plasma) extreme ultraviolet light source, and accelerator light source. Among them, LPP light source and DPP light source are the most widely used extreme ultraviolet light sources. However, both LPP light source and DPP light source are wide-spectrum light sources covering extreme ultraviolet light, ultraviolet light, visible light, and infrared light. In addition to the extreme ultraviolet component in the light source, there are also stray light components of other wavebands, which will greatly affect the imaging quality. Therefore, when using LPP light source and DPP light source for imaging, optical elements such as Mo / Si multilayer film mirrors and Zr film filters are needed to suppress stray light of other wavebands, thereby improving the spatial resolution of the system imaging.

[0043] In the related art, extreme ultraviolet imaging detectors mainly include two types: direct type detector and indirect type detector. The direct type imaging detector is sensitive to the extreme ultraviolet waveband by using back illumination, substrate thinning and other technologies, and the indirect type imaging detector converts extreme ultraviolet light into visible light by using a scintillator, and then couples the visible light to a visible light sensor for imaging by using a coupling system. The extreme ultraviolet optical imaging system can be roughly divided into two types according to the different imaging detectors used, which are direct type imaging system based on EUV CCD and indirect type imaging system based on fluorescence conversion. Among them, the imaging system based on indirect type imaging detector is widely used in extreme ultraviolet light source diagnosis, extreme ultraviolet mask detection, coronal detection, and biomedical detection, and its structure is as shown in Figure 1 .

[0044] The principle of the extreme ultraviolet optical imaging system is as shown in Figure 2 , wherein the illumination system is generally composed of multiple Mo / Si multilayer film mirrors and Zr film optical elements, and the imaging system is composed of waveband plates or Schwarzschild objective lenses and other EUV optical elements. In the entire imaging optical system, neither the Mo / Si multilayer film structure optical element nor the Zr metal thin film can completely filter out stray light of other wavebands outside the extreme ultraviolet waveband. The reflectivity spectrum distribution of the 40-period Mo / Si multilayer film structure mirror and the transmittance spectrum distribution of the 100nm-thick Zr metal thin film are as shown in Figure 3 and Figure 4 .

[0045] For an indirect imaging detector, the scintillator element is mainly composed of a cover layer and a scintillator. The cover layer has two main functions: (1) the front surface of the cover layer can block the visible light component in the incident light, which can enter the optical coupling system and be collected by the visible light image sensor, and the cover layer can avoid affecting the accuracy of the measured spot size, light intensity and other parameters; (2) the back surface of the cover layer can reflect the part of the converted visible light that propagates backward, which can increase the number of visible light photons entering the optical coupling system and increase the detection efficiency of the detector system. Al with high reflectivity for visible light is widely used as a cover layer material. However, for all filter elements of the entire optical system, including Mo / Si multilayer film mirror, Zr metal film and Al material cover layer, it is impossible to completely filter out all stray light components, and the illumination light still contains stray light components in the deep ultraviolet band of 60nm-80nm, as shown in the transmittance spectrum distribution diagram of the Zr film and the 100nm Al film structure (total thickness of 100nm), and the proportion of stray light in the DPP broadband extreme ultraviolet light source is high. If the stray light in this band is not completely filtered out, it will greatly affect the imaging quality. Figure 5

[0046] The filtering effect of stray light in the related art is not good, and the imaging quality of the extreme ultraviolet imaging system is greatly affected, in order to solve these technical problems in the related art, the application provides a filter structure as a filter optical element for extreme ultraviolet light imaging stray light suppression, by using a composite structure of Zr, Mo, Al or a composite structure of Zr, Nb, Al or a composite structure of Zr, ZrN, Al, the light in the 60nm-80nm band of stray light can be filtered out, greatly eliminating the influence of all band stray light, thereby improving the imaging quality of extreme ultraviolet imaging.

[0047] As shown in Figure 6 An embodiment of the application provides a filter structure, which comprises a zirconium film, an intermediate layer film and an aluminum film stacked in order from bottom to top; the intermediate layer film comprises a molybdenum film, a niobium film or a zirconium nitride film.

[0048] In some embodiments of the application, the thickness of the zirconium film is 50nm-200nm, the thickness of the intermediate layer film is 30nm-100nm, and the thickness of the aluminum film is 30nm-150nm. Through a large number of experiments, it is determined that by setting the thickness of the zirconium film to 50nm-200nm, the thickness of the intermediate layer film to 30nm-100nm, and the thickness of the aluminum film to 30nm-150nm, the filter structure can meet the size application requirements of the filter structure, and the filter requirements of the actual application can be met.

[0049] ​In some embodiments of the present application, the thickness of the zirconium film is 100 nm, the thickness of the intermediate layer film is 50 nm, and the thickness of the aluminum film is 100 nm. Through a large number of experiments, it is determined that when the thickness of the zirconium film is set to 100 nm, the thickness of the intermediate layer film is set to 50 nm, and the thickness of the aluminum film is set to 100 nm, the best light filtering effect can be achieved while meeting the application requirements of the light filtering structure size.

[0050] In some embodiments of the present application, the thickness of the zirconium film can be 50 nm, the thickness of the intermediate layer film can be 30 nm, and the thickness of the aluminum film can be 30 nm. Through a large number of experiments, it is determined that when the thickness of the zirconium film is set to 50 nm, the thickness of the intermediate layer film is set to 30 nm, and the thickness of the aluminum film is set to 30 nm, a better light filtering effect can be achieved while meeting the application requirements of the light filtering structure size.

[0051] In some embodiments of the present application, the thickness of the zirconium film can be 200 nm, the thickness of the intermediate layer film can be 100 nm, and the thickness of the aluminum film can be 150 nm. Through a large number of experiments, it is determined that when the thickness of the zirconium film is set to 200 nm, the thickness of the intermediate layer film is set to 100 nm, and the thickness of the aluminum film is set to 150 nm, a better light filtering effect can be achieved while meeting the application requirements of the light filtering structure size.

[0052] The light filtering structure provided by the embodiments of the present application includes a zirconium film, an intermediate layer film and an aluminum film stacked in turn from bottom to top, and the intermediate layer film includes a molybdenum film, a niobium film or a zirconium nitride film. The intermediate layer film further improves the filtering rate of stray light. Therefore, the light filtering structure of the embodiments can filter out stray light to a great extent, greatly eliminates the influence of stray light, and thus improves the imaging quality of extreme ultraviolet imaging, thereby solving the technical problems of poor filtering effect of stray light, great influence of stray light and low imaging quality of the extreme ultraviolet imaging system in the related art.

[0053] Another embodiment of the present application provides a manufacturing method of a light filtering structure, including:

[0054] providing a zirconium film with a first preset thickness;

[0055] coating an intermediate layer film with a second preset thickness on the zirconium film, the intermediate layer film including a molybdenum film, a niobium film or a zirconium nitride film;

[0056] coating an aluminum film with a third preset thickness on the intermediate layer film to obtain a light filtering structure.

[0057] The first preset thickness ranges from 50nm to 200nm, the second preset thickness ranges from 30nm to 100nm, and the third preset thickness ranges from 30nm to 150nm, which can meet the application requirements of filter structure size and the actual manufacturing process requirements.

[0058] In some embodiments, depositing a second predetermined thickness of intermediate layer film on the zirconium film includes:

[0059] A molybdenum film of a fourth predetermined thickness is deposited on the zirconium film;

[0060] A niobium film of a fifth predetermined thickness is deposited on the surface of the molybdenum film;

[0061] A zirconium nitride film of a sixth preset thickness is deposited on the niobium film to complete the coating operation of the intermediate layer film.

[0062] The sum of the fourth preset thickness, the fifth preset thickness, and the sixth preset thickness is equal to the second preset thickness.

[0063] By pre-setting the thickness of each film layer, the adverse effects of non-compliance with the thickness of each film layer on the manufacturing process can be avoided, ensuring that a filter structure that meets the actual application requirements is obtained.

[0064] The filter structure manufactured by the method of this embodiment can filter out stray light to a large extent, greatly eliminating the influence of stray light, thereby improving the imaging quality of extreme ultraviolet imaging. It solves the technical problems in related technologies where the filtering effect of stray light is not good, and the system is greatly affected by stray light, resulting in low imaging quality of the extreme ultraviolet imaging system.

[0065] like Figure 10 As shown, another embodiment of this application provides an extreme ultraviolet indirect imaging system, including a scintillator, the above-described filter structure, a coupling system, and a visible light sensor; the filter structure is disposed on the scintillator; the scintillator is used to convert extreme ultraviolet light passing through the filter structure into visible light, and the coupling system is used to couple the visible light to the visible light sensor for imaging.

[0066] In this embodiment, the filter structure of the extreme ultraviolet (EUV) indirect imaging system is a composite structure such as a Zr film, a Mo film, and an Al film, or a Zr film, a Nb film, and an Al film. By utilizing the filtering effect of materials such as Mo / Nb / ZrN in the deep ultraviolet band, the shortcomings of related technologies' filter structures in filtering 60nm-80nm deep ultraviolet light components are overcome. While minimizing the attenuation of EUV light intensity, the influence of 60nm-80nm stray light on imaging is further eliminated, thus further improving the imaging quality of the EUV indirect imaging system. The transmittance distribution of the Zr film and Al film filter structures in the 0nm-1000nm spectrum of related technologies was calculated using Macleod simulation software, as shown below. Figure 5 The transmittance spectrum of the Zr film and the 100nm Al film structure (total thickness 100nm) is shown. The transmittance is about 13.2% near 13.5nm, and there is a small peak of about 0.4% near the deep ultraviolet band (60nm-80nm) at 70nm.

[0067] In a specific example, the filter structure of the extreme ultraviolet indirect imaging system is a composite structure of a Zr film, a Mo film, and an Al film. The transmittance distribution of this composite structure (100nm Zr film, 50nm Mo film, and 100nm Al film) in the 0nm-1000nm spectrum, calculated using Macleod simulation software, is shown below. Figure 7 The transmittance spectrum of the structure shown is Zr film + 50nm Mo film + 100nm Al film (total thickness 100nm). Compare with... Figure 5 The transmittance spectral distribution of the Zr film and the 100nm Al film structure (total thickness 100nm) shown can be seen to completely filter out the stray light peaks near 70nm, and the transmittance near 13.5nm is about 9.5%, which is slightly lower than the extreme ultraviolet transmittance of the filter structure in related technologies.

[0068] In another specific example, the filter structure of the extreme ultraviolet indirect imaging system is a composite structure of a Zr film, a Nb film, and an Al film. The transmittance distribution of this composite structure (100nm Zr film, 50nm Nb film, and 100nm Al film) in the 0nm-1000nm spectrum, calculated using Macleod simulation software, is shown below. Figure 8 The transmittance spectral distributions of the Zr film + 50nm Nb film and 100nm Al film structures (total thickness 100nm) are shown. (Comparison) Figure 5The transmittance spectrum distribution of the Zr film and 100nm Al film structure (total thickness of 100nm) shown in the figure can be found that the stray light wave peak near 70nm is completely filtered out, and the transmittance near 13.5nm is about 10.6%, and the transmittance of extreme ultraviolet light is comparable to the filtering structure in the related art.

[0069] In another specific example, the filtering structure of the extreme ultraviolet indirect imaging system is a composite structure of Zr film, ZrN film and Al film. The transmittance distribution of the 100nm Zr film, 50nm ZrN film and 100nm Al film composite structure in the 0nm-1000nm spectrum calculated by the Macleod simulation software is as shown in the figure Figure 9 The transmittance spectrum distribution of the Zr film + 50nm ZrN film + 100nm Al film structure (total thickness of 100nm) shown in the figure. Compared with Figure 5 The transmittance spectrum distribution of the Zr film and 100nm Al film structure (total thickness of 100nm) shown in the figure can be found that the stray light wave peak near 70nm is completely filtered out, and the transmittance near 13.5nm is about 10%, which is slightly lower than the transmittance of extreme ultraviolet light of the filtering structure in the related art.

[0070] It should be noted that for the overall filtering structure, a 50nm thick Mo / Nb / ZrN film can be coated before or after the Zr metal thin film, and a 100nm thick Al film can be coated on the surface of the scintillator element to form a new filtering element. A 50nm thick Mo / Nb / ZrN film can be further coated on the surface of the Al film of the scintillator to form a new scintillator element. Or a separate Mo / Nb / ZrN film can be added to the system as a new filtering element. Or other combinations of different thicknesses and structures of the three materials.

[0071] In addition, the materials mentioned in the above embodiments are only a part of the filtering materials protected by the present application. It should be understood that all other filtering materials capable of filtering out stray light in the 60nm-80nm deep ultraviolet band, and other structures capable of filtering out stray light in the 60nm-80nm deep ultraviolet band, are also within the protection scope of the cover layer material.

[0072] The extreme ultraviolet indirect imaging system provided by the embodiments of the present application can filter out stray light to a great extent, greatly reducing the influence of stray light, thereby improving the imaging quality of the extreme ultraviolet imaging, and solving the technical problems of poor filtering effect of stray light, great influence of stray light and low imaging quality of the extreme ultraviolet imaging system in the related art.

[0073] Reference Figure 11As shown, another embodiment of the present application provides an extreme ultraviolet indirect imaging method, which is implemented by the extreme ultraviolet indirect imaging system described above; the method comprises steps S10 to S30:

[0074] S10, extreme ultraviolet light passes through the light filtering structure to obtain filtered light;

[0075] S20, the scintillator converts the filtered light into visible light;

[0076] S30, the coupling system couples the visible light to the visible light sensor to form an image.

[0077] In the extreme ultraviolet light passes through the light filtering structure to obtain filtered light, the extreme ultraviolet light passes through the zirconium film, the intermediate layer film and the aluminum film in sequence to obtain the filtered light.

[0078] The extreme ultraviolet indirect imaging method provided by the embodiment of the present application greatly filters out stray light through the light filtering structure, greatly eliminates the influence of stray light, thereby improving the imaging quality of the extreme ultraviolet imaging, and solving the technical problems of poor filtering effect of stray light, great influence of stray light and low imaging quality of the extreme ultraviolet imaging system in the related art.

[0079] It should be noted that:

[0080] It should be understood that, although each step in the flowchart of the accompanying drawings is shown in sequence according to the direction of the arrow, these steps are not necessarily executed in sequence according to the direction of the arrow. Unless otherwise specified herein, the execution of these steps is not strictly limited in sequence, and they can be executed in other sequences. Moreover, at least part of the steps in the flowchart of the accompanying drawings can include multiple sub-steps or multiple stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution sequence is not necessarily sequential, but can be executed in rotation or alternation with at least part of other steps or sub-steps or stages of other steps.

[0081] The above-described embodiments only express the implementation of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent of the present application. It should be noted that, for ordinary skilled persons in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of protection of the present application. Therefore, the scope of protection of the present application should be subject to the appended claims.

Claims

1. A filter structure, characterized in that, It includes a zirconium film, an intermediate layer film, and an aluminum film stacked sequentially from bottom to top; the intermediate layer film includes a molybdenum film, a niobium film located on the molybdenum film, and a zirconium nitride film located on the niobium film.

2. The filter structure according to claim 1, characterized in that, The zirconium film has a thickness of 50nm-200nm, the intermediate layer film has a thickness of 30nm-100nm, and the aluminum film has a thickness of 30nm-150nm.

3. The filter structure according to claim 1 or 2, characterized in that, The zirconium film has a thickness of 100 nm, the intermediate layer film has a thickness of 50 nm, and the aluminum film has a thickness of 100 nm.

4. The filter structure according to claim 1 or 2, characterized in that, The zirconium film has a thickness of 50 nm, the intermediate layer film has a thickness of 30 nm, and the aluminum film has a thickness of 30 nm.

5. The filter structure according to claim 1 or 2, characterized in that, The zirconium film has a thickness of 200 nm, the intermediate layer film has a thickness of 100 nm, and the aluminum film has a thickness of 150 nm.

6. A method for manufacturing a filter structure, characterized in that, include: Provide a zirconium film of a first preset thickness; A second predetermined thickness intermediate layer film is deposited on the zirconium film, the intermediate layer film comprising a molybdenum film, a niobium film located on the molybdenum film, and a zirconium nitride film located on the niobium film; An aluminum film of a third preset thickness is deposited on the intermediate layer film to obtain a filter structure.

7. The method for manufacturing the filter structure according to claim 6, characterized in that, The process of depositing an intermediate layer film of a second predetermined thickness on the zirconium film includes: A molybdenum film of a fourth predetermined thickness is deposited on the zirconium film; A niobium film of a fifth predetermined thickness is deposited on the surface of the molybdenum film; A zirconium nitride film of a sixth preset thickness is deposited on the niobium film to complete the coating operation of the intermediate layer film; The sum of the fourth preset thickness, the fifth preset thickness, and the sixth preset thickness is equal to the second preset thickness.

8. An extreme ultraviolet indirect imaging system, characterized in that, The invention includes a scintillator, a filter structure according to any one of claims 1-5, a coupling system, and a visible light sensor; the filter structure is disposed on the scintillator; the scintillator is used to convert extreme ultraviolet light passing through the filter structure into visible light, and the coupling system is used to couple the visible light to the visible light sensor for imaging.

9. An extreme ultraviolet indirect imaging method, characterized in that, This is achieved using the extreme ultraviolet indirect imaging system as described in claim 8; the method includes: Extreme ultraviolet light passes through the aforementioned filter structure to obtain filtered light; The scintillator converts the filtered light into visible light; The coupling system couples the visible light to the visible light sensor for imaging.

10. The method according to claim 9, characterized in that, The extreme ultraviolet light passes through the filter structure to obtain filtered light, including: the extreme ultraviolet light sequentially passes through the zirconium film, the intermediate layer film and the aluminum film to obtain filtered light.

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