Extreme ultraviolet lithography projection exposure optical system and method

Abstract

The invention relates to the technical field of projection optics, in particular to an extreme ultraviolet lithography projection exposure optical system and method.The extreme ultraviolet lithography projection exposure optical system comprises a light field uniformity adjusting module, and the light field uniformity adjusting module is in signal connection with a light beam generating module and a light beam shaping module; the light field uniformity adjusting module is used for acquiring light intensity distribution data of the extreme ultraviolet light beams output by the light beam shaping module; the control module is also used for adjusting the output power of the light beam generation module according to the light intensity distribution data, so that the lowest light intensity in the light intensity distribution data of the extreme ultraviolet light beams output by the light beam shaping module after power adjustment is not lower than the target light intensity; and the control module is also used for adjusting the light transmittance of a gradient attenuation sheet in the extreme ultraviolet light beam shaping module according to the light intensity distribution data of the extreme ultraviolet light beams output by the light beam shaping module after the power adjustment, so that the light intensity difference of any two positions in the light intensity distribution data of the extreme ultraviolet light beams output by the light beam shaping module after the light transmittance adjustment does not exceed a difference limit range.

Description

Technical Field

[0001] The invention relates to the technical field of projection optics, and in particular to an extreme ultraviolet lithography projection exposure optical system and method. Background Art

[0002] In the extreme ultraviolet lithography (EUVL) process, the uniformity of the light field is one of the core requirements for achieving high-precision chip manufacturing. The wavelength of the light source for EUV lithography is extremely short (about 13.5 nanometers), which enables it to achieve pattern resolutions of 7 nanometers and below process nodes. However, EUV light is easily attenuated when propagating in the air, and is also extremely sensitive to environmental factors (such as temperature changes, vibrations, air pressure fluctuations, etc.), resulting in the light field being not uniform enough in practical applications, which can have a significant impact on the accuracy of the lithography pattern.

[0003] In actual manufacturing, insufficient light field uniformity not only affects the chip manufacturing yield, but also increases the scrap rate and rework costs. Due to the high uniformity requirements of the light field in nanoscale chip manufacturing, the light source output of the traditional EUVL system is difficult to adjust in real time, and the dynamic optimization capability of the light field distribution is weak. This limitation makes it difficult to cope with the real-time fluctuations of the light field during the actual projection process, affecting the exposure accuracy and clarity of the pattern, and ultimately leading to a decrease in yield and an increase in manufacturing costs. Summary of the invention

[0004] The present invention provides an extreme ultraviolet lithography projection exposure optical system and method, aiming to solve the problem of light field uniformity during the extreme ultraviolet lithography projection exposure process.

[0005] In a first aspect, the ultraviolet lithography projection exposure optical system provided by the present invention comprises a beam generating module, a beam shaping module and a beam projection module, wherein the beam generating module is used to generate an extreme ultraviolet beam, the beam shaping module is used to adjust the extreme ultraviolet beam, and the beam projection module is used to project the adjusted extreme ultraviolet beam onto a target surface; further, the ultraviolet lithography projection exposure optical system provided by the present invention further comprises a light field uniformity adjustment module, wherein the light field uniformity adjustment module is respectively connected to the beam generating module and the beam shaping module by signal; the light field uniformity adjustment module is used to obtain the output of the beam shaping module The light field uniformity adjustment module is further used to adjust the output power of the light beam generating module according to the light intensity distribution data, so that the lowest light intensity in the light intensity distribution data of the extreme ultraviolet light beam output by the beam shaping module after the power adjustment is not lower than the target light intensity; the light field uniformity adjustment module is further used to adjust the transmittance of the gradient attenuation plate in the extreme ultraviolet beam shaping module according to the light intensity distribution data of the extreme ultraviolet light beam output by the beam shaping module after the power adjustment, so that the light intensity difference between any two positions in the light intensity distribution data of the extreme ultraviolet light beam output by the beam shaping module after the transmittance adjustment does not exceed the difference limit range.

[0006] Optionally, the light field uniformity adjustment module includes: a light intensity distribution data acquisition submodule and a light intensity uniformity adjustment submodule: the light intensity distribution data acquisition submodule is arranged on the light output side of the beam shaping module, and is used to obtain the light intensity distribution data of the extreme ultraviolet light beam output by the beam shaping module, and the light intensity distribution data of the extreme ultraviolet light beam is the light intensity of the extreme ultraviolet light beam at various positions on the projection plane perpendicular to the light path direction; the light intensity uniformity adjustment submodule is connected to the beam generating module signal, and is used to adjust the output power of the beam generating module according to the light intensity distribution data of the extreme ultraviolet light beam, so that the lowest light intensity in the light intensity distribution data obtained after the power adjustment is not lower than the target light intensity; the light intensity uniformity adjustment submodule is connected to the beam shaping module signal, and is used to adjust the transmittance of the gradient attenuation plate in the extreme ultraviolet beam shaping module according to the light intensity distribution data of the extreme ultraviolet light beam output by the beam shaping module after the power adjustment, so that the light intensity difference between any two positions in the light intensity distribution data of the extreme ultraviolet light beam output by the beam shaping module after the transmittance adjustment does not exceed the difference limit range.

[0007] Optionally, the light intensity distribution data acquisition submodule is composed of a plurality of photoelectric detectors arranged in a planar array, and any photoelectric detector is used to obtain a local light intensity value at a location.

[0008] Optionally, the beam shaping module includes multiple gradient attenuation sheets, any one of which is arranged on the light-emitting side of the beam generating module and perpendicular to the direction of the light path, and is used to adjust the transmittance of the extreme ultraviolet light beam; the multiple photodetectors correspond one-to-one to the multiple gradient attenuation sheets, respectively, and any one of the gradient attenuation sheets is used to adjust the transmittance of the local light beam collected by the corresponding photodetector.

[0009] In a second aspect, the EUV lithography projection exposure method applicable to an EUV lithography projection exposure optical system provided by the present invention comprises the following steps: the beam generating module generates an EUV beam; the beam shaping module adjusts the EUV beam; the light field uniformity adjustment module obtains the EUV beam intensity distribution data output by the beam shaping module; the light field uniformity adjustment module adjusts the output power of the beam generating module according to the intensity distribution data, so that the lowest light intensity in the EUV beam intensity distribution data output by the beam shaping module after the power adjustment is not lower than the target light intensity; the light field uniformity adjustment module adjusts the transmittance of the gradient attenuation plate in the EUV beam shaping module according to the EUV beam intensity distribution data output by the beam shaping module after the power adjustment, so that the light intensity difference between any two positions in the EUV beam intensity distribution data output by the beam shaping module after the transmittance adjustment does not exceed the difference limit range; the beam projection module projects the EUV beam output by the beam shaping module after the transmittance adjustment onto the target surface.

[0010] Optionally, adjusting the output power of the beam generating module according to the light intensity distribution data so that the minimum light intensity in the extreme ultraviolet light beam intensity distribution data output by the beam shaping module after the power adjustment is not lower than the target light intensity includes the following steps: extracting the minimum light intensity in the light intensity distribution data; setting the target light intensity, and comparing the numerical values ​​of the minimum light intensity and the target light intensity; and adjusting the output power of the beam generating module according to the comparison result of the numerical values ​​of the minimum light intensity and the target light intensity.

[0011] Optionally, the output power of the beam generating module satisfies the following adjustment rules: if the minimum light intensity is lower than the target light intensity, the output power of the extreme ultraviolet light source module is increased until the minimum light intensity in the extreme ultraviolet beam intensity distribution data output by the beam shaping module after adjustment is not lower than the target light intensity; if the minimum light intensity is not lower than the target light intensity, the current output power of the extreme ultraviolet light source module is maintained.

[0012] Optionally, the method of adjusting the transmittance of the gradient attenuation plate in the extreme ultraviolet beam shaping module according to the extreme ultraviolet beam intensity distribution data output by the beam shaping module after the power adjustment, so that the light intensity difference between any two positions in the extreme ultraviolet beam intensity distribution data output by the beam shaping module after the transmittance adjustment does not exceed the difference limit range, includes the following steps: obtaining a uniform reference light intensity based on the extreme ultraviolet beam intensity distribution data output by the beam shaping module after the power adjustment, wherein the uniform reference light intensity is a reference light intensity for measuring the uniformity of light intensity distribution; respectively obtaining the difference between each light intensity in the extreme ultraviolet beam intensity distribution data output by the beam shaping module after the power adjustment and the uniform reference light intensity; setting a difference limit range, and setting the light intensity whose difference with the uniform reference light intensity does not meet the difference limit range as an abnormal light intensity; respectively adjusting the transmittance of the gradient attenuation plate corresponding to each abnormal light intensity position, so that the light intensity difference between any two positions in the extreme ultraviolet beam intensity distribution data output by the beam shaping module after the transmittance adjustment does not exceed the difference limit range.

[0013] Optionally, the transmittance of any gradient attenuation plate in the extreme ultraviolet beam shaping module satisfies the following rule: if the difference between the abnormal light intensity and the uniform reference light intensity is lower than any light intensity within the difference limit range, the transmittance of the gradient attenuation plate corresponding to the abnormal light intensity position is increased; if the difference between the abnormal light intensity and the uniform reference light intensity is higher than any light intensity within the difference limit range, the transmittance of the gradient attenuation plate corresponding to the abnormal light intensity position is reduced.

[0014] The extreme ultraviolet lithography projection exposure optical system and method provided by the present invention have the following benefits: the present invention obtains and analyzes light intensity distribution data, adjusts the beam generation and shaping modules, and gradually reduces the light intensity difference, thereby achieving light field uniformity to ensure the exposure accuracy and clarity of the pattern, thereby improving the dynamic adjustment capability of the light field during the lithography process. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A schematic diagram of the composition of an extreme ultraviolet lithography projection exposure optical system module provided by an embodiment of the present invention;

[0016] Figure 2 A schematic diagram of the composition of a light field uniformity adjustment module provided in an embodiment of the present invention;

[0017] Figure 3 A flow chart of an extreme ultraviolet lithography projection exposure method provided by an embodiment of the present invention;

[0018] Figure 4 A schematic diagram of light transmittance adjustment provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0019] In the following description, for the purpose of explanation rather than limitation, specific details such as specific system structures and technologies are proposed to facilitate a thorough understanding of the embodiments of the present application.

[0020] Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings and other implementation methods can be obtained based on these drawings without any creative work.

[0021] In one embodiment, see Figure 1 , Figure 1 This is a schematic diagram of the composition of the EUV lithography projection exposure optical system modules provided by an embodiment of the present invention.

[0022] like Figure 1 As shown, the EUV lithography projection exposure optical system provided by the present invention includes a beam generating module, a beam shaping module and a beam projection module; further, the EUV lithography projection exposure optical system also includes a light field uniformity adjustment module for adjusting the light field uniformity.

[0023] In this embodiment, the light beam generating module is used to generate an extreme ultraviolet light beam. It can be known that the wavelength of the extreme ultraviolet light beam generated by the present invention is electromagnetic radiation in the range of 10 nanometers to 121 nanometers.

[0024] Furthermore, the beam generating module uses laser plasma (LPP) technology to generate the extreme ultraviolet beam, that is, a high-power laser is used to hit a tin droplet target to plasmatize the tin droplet target to generate an extreme ultraviolet beam.

[0025] In this embodiment, the beam shaping module is used to adjust the extreme ultraviolet light beam; further, the beam shaping module includes a plurality of gradient attenuation sheets, any one of which is arranged on the light output side of the beam generating module and is perpendicular to the light path direction, so as to adjust the transmittance of the extreme ultraviolet light beam.

[0026] Furthermore, the beam shaping module adjusts the extreme ultraviolet beam generated by the beam generating module through focusing, collimation, homogenization, size adjustment and other operations to achieve uniform distribution and size optimization of the light field, ensuring that the beam reaches a predetermined light intensity uniformity and a suitable size range during the projection exposure process.

[0027] In this embodiment, the beam projection module is used to project the adjusted extreme ultraviolet beam onto a target surface; further, the target surface is a silicon wafer surface. In one or some other embodiments, the target surface may also be other substrate surfaces such as glass, sapphire, or metal film.

[0028] In this embodiment, the light field uniformity adjustment module is signal-connected to the light beam generating module and the light beam shaping module respectively.

[0029] Furthermore, the light field uniformity adjustment module is used to obtain the light intensity distribution data of the extreme ultraviolet light beam output by the beam shaping module.

[0030] Specifically, the extreme ultraviolet light beam intensity distribution data is the intensity of the extreme ultraviolet light beam at various positions on a projection plane perpendicular to the light path direction.

[0031] Furthermore, the light field uniformity adjustment module is also used to adjust the output power of the beam generating module according to the light intensity distribution data, so that the lowest light intensity in the extreme ultraviolet light beam intensity distribution data output by the beam shaping module after power adjustment is not lower than the target light intensity.

[0032] It is understandable that the target light intensity is a preset light intensity standard determined based on factors such as the specific requirements of the lithography process, the characteristics of the photoresist, and the accuracy of the target pattern, to ensure that the intensity of the EUV light beam at each position on the projection cross section is sufficient for subsequent lithography processes.

[0033] Furthermore, the light field uniformity adjustment module is also used to adjust the transmittance of the gradient attenuation plate in the extreme ultraviolet beam shaping module according to the extreme ultraviolet beam intensity distribution data output by the beam shaping module after power adjustment, so that the light intensity difference between any two positions in the extreme ultraviolet beam intensity distribution data output by the beam shaping module after the transmittance adjustment does not exceed the difference limit range.

[0034] It can be understood that the difference limit range is a predetermined light intensity difference limit range, which is used to measure whether the uniformity of the adjusted extreme ultraviolet light beam intensity distribution meets the requirements, and is usually determined based on the accuracy requirements of the lithography process, the sensitivity of the photoresist to light intensity changes, etc.

[0035] In one embodiment, see Figure 2 , Figure 2 This is a schematic diagram of the composition of the light field uniformity adjustment module provided in an embodiment of the present invention.

[0036] like Figure 2 As shown, the light field uniformity adjustment module includes a light intensity distribution data acquisition submodule and a light intensity uniformity adjustment submodule.

[0037] Furthermore, the light intensity distribution data acquisition submodule is arranged on the light output side of the beam shaping module, and is used to obtain the light intensity distribution data of the extreme ultraviolet light beam output by the beam shaping module.

[0038] In this embodiment, the light intensity distribution data acquisition submodule is composed of a plurality of photoelectric detectors arranged in a planar array, and any photoelectric detector is used to obtain a local light intensity value at the location.

[0039] Furthermore, in order to adjust the transmittance of the extreme ultraviolet light beam at different positions, the multiple photodetectors correspond one-to-one to the multiple gradient attenuation sheets respectively, and any gradient attenuation sheet is used to adjust the transmittance of the local light beam collected by the corresponding photodetector.

[0040] See also Figure 3 , Figure 3 Schematic diagram of light transmittance adjustment provided by an embodiment of the present invention. Figure 3 As shown, the light intensity distribution data acquisition submodule provided in this embodiment includes four photodetectors arranged in a planar array on the light-emitting side of the beam shaping module; the beam shaping module provided in this embodiment includes four gradient attenuation plates, any one of which is arranged on the light-emitting side of the beam generating module and is perpendicular to the direction of the light path.

[0041] Furthermore, the first gradient attenuation sheet A1 corresponds to the first photodetector C1, and the first gradient attenuation sheet A1 is used to adjust the transmittance of the local light beam collected by the first photodetector C1; the second gradient attenuation sheet A2 corresponds to the second photodetector C2, and the second gradient attenuation sheet A2 is used to adjust the transmittance of the local light beam collected by the second photodetector C2; the third gradient attenuation sheet A3 corresponds to the third photodetector C3, and the third gradient attenuation sheet A3 is used to adjust the transmittance of the local light beam collected by the third photodetector C3; the fourth gradient attenuation sheet A4 corresponds to the fourth photodetector C4, and the fourth gradient attenuation sheet A4 is used to adjust the transmittance of the local light beam collected by the fourth photodetector C4.

[0042] It should be noted that the projection surfaces of any two gradient attenuation sheets in the direction of the optical path are the same, and any gradient attenuation sheet includes a first area and a second area, the transmittance of the first area is adjustable, and the local light beam passing through the first area is received by the corresponding photodetector, the transmittance of the second area is fixed, and the transmittance of the second area in any two gradient attenuation sheets is the same. Furthermore, the transmittance adjustment of any first area can be achieved by replacing the gradient attenuation sheet with a first area of ​​different thickness.

[0043] Furthermore, the light intensity uniformity adjustment submodule is signal-connected to the light beam generating module, and is used to adjust the output power of the light beam generating module according to the extreme ultraviolet light beam intensity distribution data, so that the lowest light intensity in the light intensity distribution data obtained after the power adjustment is not lower than the target light intensity.

[0044] Furthermore, the light intensity uniformity adjustment submodule is signal-connected to the beam shaping module, and is used to adjust the transmittance of the gradient attenuation plate in the extreme ultraviolet beam shaping module according to the extreme ultraviolet beam intensity distribution data output by the beam shaping module after power adjustment, so that the light intensity difference between any two positions in the extreme ultraviolet beam intensity distribution data output by the beam shaping module after the transmittance adjustment does not exceed the difference limit range.

[0045] In one embodiment, see Figure 4 , Figure 4 This is a flow chart of the extreme ultraviolet lithography projection exposure method provided in an embodiment of the present invention.

[0046] like Figure 3 As shown, based on the extreme ultraviolet lithography projection exposure optical system provided by the present invention, the extreme ultraviolet lithography projection exposure method provided by the embodiment of the present invention includes the following steps:

[0047] S01. The beam generating module generates an extreme ultraviolet beam.

[0048] Furthermore, the light beam generating module described in step S01 generates an extreme ultraviolet light beam through laser plasma technology, which is a prior art and will not be described in detail here.

[0049] S02. The beam shaping module adjusts the extreme ultraviolet beam.

[0050] Furthermore, in the process of adjusting the extreme ultraviolet light beam by the beam shaping module described in step S02, operations such as focusing operation, collimation operation and size adjustment are prior arts and will not be described in detail here.

[0051] In this embodiment, the beam shaping module adjusts the transmittance of the gradient attenuation plate to make the intensity distribution of the light beam on the entire propagation path more uniform.

[0052] S03. The light field uniformity adjustment module obtains the light intensity distribution data of the extreme ultraviolet light beam output by the beam shaping module.

[0053] It can be understood that the extreme ultraviolet light beam intensity distribution data refers to the light intensity data set of the extreme ultraviolet light beam adjusted by the extreme ultraviolet beam shaping module at each position on the projection cross section perpendicular to the light path direction thereof.

[0054] S04. The light field uniformity adjustment module adjusts the output power of the light beam generating module according to the light intensity distribution data, so that the lowest light intensity in the extreme ultraviolet light beam intensity distribution data output by the beam shaping module after the power adjustment is not lower than the target light intensity.

[0055] Furthermore, step S04 specifically includes the following steps:

[0056] S041. Extracting the lowest light intensity in the light intensity distribution data.

[0057] S042: Set a target light intensity, and compare the minimum light intensity with the target light intensity.

[0058] In this embodiment, the target light intensity is determined by relevant staff according to factors such as specific requirements of the photolithography process, characteristics of the photoresist, and accuracy of the target pattern.

[0059] S043. Adjust the output power of the light beam generating module according to a comparison result between the minimum light intensity and the target light intensity.

[0060] Furthermore, the output power of the beam generating module satisfies the following adjustment rules:

[0061] If the minimum light intensity is lower than the target light intensity, increase the output power of the extreme ultraviolet light source module until the minimum light intensity in the extreme ultraviolet light beam intensity distribution data output by the adjusted beam shaping module is not lower than the target light intensity; if the minimum light intensity is not lower than the target light intensity, maintain the current output power of the extreme ultraviolet light source module.

[0062] S05. The light field uniformity adjustment module adjusts the transmittance of the gradient attenuation plate in the extreme ultraviolet beam shaping module according to the extreme ultraviolet beam intensity distribution data output by the beam shaping module after the power adjustment, so that the light intensity difference between any two positions in the extreme ultraviolet beam intensity distribution data output by the beam shaping module after the transmittance adjustment does not exceed the difference limit range.

[0063] Furthermore, step S05 specifically includes the following steps:

[0064] S051. Obtaining a uniform reference light intensity based on the light intensity distribution data of the extreme ultraviolet light beam output by the beam shaping module after power adjustment.

[0065] In this embodiment, the uniform reference light intensity is a reference light intensity for measuring the uniformity of light intensity distribution, which satisfies the following generation model: Among them, I c Indicates the uniform reference light intensity, It indicates that after the power adjustment, the intensity distribution data of the extreme ultraviolet beam output by the beam shaping module is such that The maximum light intensity is obtained, I represents the data set corresponding to the extreme ultraviolet light intensity distribution data output by the beam shaping module after power adjustment, i represents the light intensity number, j represents the light intensity number, I i Indicates the i-th light intensity in the data set, I j Represents the jth light intensity in the data set.

[0066] S052, respectively obtaining the difference between each light intensity in the extreme ultraviolet light beam intensity distribution data output by the beam shaping module after power adjustment and the uniform reference light intensity.

[0067] S053, setting a difference limit range, and setting the light intensity whose difference with the uniform reference light intensity does not satisfy the difference limit range as abnormal light intensity.

[0068] In this embodiment, the difference limit range is determined by relevant staff according to the accuracy requirements of the photolithography process, the sensitivity of the photoresist to changes in light intensity and other relevant conditions.

[0069] S054, respectively adjusting the transmittance of the gradient attenuation plate corresponding to each abnormal light intensity position, so that the light intensity difference between any two positions in the extreme ultraviolet light beam intensity distribution data output by the beam shaping module after the transmittance adjustment does not exceed the difference limit range.

[0070] S06, the beam projection module projects the extreme ultraviolet beam output by the beam shaping module after the transmittance is adjusted onto a target surface.

[0071] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0072] It should be noted that the above embodiments can be freely combined as needed. The above is only a preferred implementation of the present invention; it should be noted that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An extreme ultraviolet lithography projection exposure optical system, comprising a beam generating module, a beam shaping module and a beam projection module, wherein the beam generating module is used to generate an extreme ultraviolet beam, the beam shaping module is used to adjust the extreme ultraviolet beam, and the beam projection module is used to project the adjusted extreme ultraviolet beam onto a target surface, characterized in that: Also includes: A light field uniformity adjustment module, wherein the light field uniformity adjustment module is signal-connected to the light beam generating module and the light beam shaping module respectively; The light field uniformity adjustment module is used to obtain the light intensity distribution data of the extreme ultraviolet light beam output by the beam shaping module; The light field uniformity adjustment module is further used to adjust the output power of the light beam generation module according to the light intensity distribution data, so that the lowest light intensity in the extreme ultraviolet light beam intensity distribution data output by the beam shaping module after the power adjustment is not lower than the target light intensity; The light field uniformity adjustment module is also used to adjust the transmittance of the gradient attenuation plate in the extreme ultraviolet beam shaping module according to the extreme ultraviolet beam intensity distribution data output by the beam shaping module after power adjustment, so that the light intensity difference between any two positions in the extreme ultraviolet beam intensity distribution data output by the beam shaping module after the transmittance adjustment does not exceed the difference limit range.

2. The extreme ultraviolet lithography projection exposure optical system according to claim 1, characterized in that: The light field uniformity adjustment module comprises: Light intensity distribution data acquisition submodule and light intensity uniformity adjustment submodule: The light intensity distribution data acquisition submodule is arranged at the light output side of the beam shaping module, and is used to obtain the light intensity distribution data of the extreme ultraviolet light beam output by the beam shaping module, wherein the light intensity distribution data of the extreme ultraviolet light beam is the light intensity of the extreme ultraviolet light beam at each position on a projection plane perpendicular to the light path direction; The light intensity uniformity adjustment submodule is connected to the light beam generation module signal, and is used to adjust the output power of the light beam generation module according to the light intensity distribution data of the extreme ultraviolet light beam, so that the lowest light intensity in the light intensity distribution data obtained after the power adjustment is not lower than the target light intensity. The light intensity uniformity adjustment submodule is signal-connected to the beam shaping module, and is used to adjust the transmittance of the gradient attenuation plate in the extreme ultraviolet beam shaping module according to the extreme ultraviolet beam intensity distribution data output by the beam shaping module after power adjustment, so that the light intensity difference between any two positions in the extreme ultraviolet beam intensity distribution data output by the beam shaping module after the transmittance adjustment does not exceed the difference limit range.

3. The extreme ultraviolet lithography projection exposure optical system according to claim 2, characterized in that: The light intensity distribution data acquisition submodule is composed of a plurality of photoelectric detectors arranged in a planar array, and any photoelectric detector is used to obtain a local light intensity value at a location.

4. The extreme ultraviolet lithography projection exposure optical system according to claim 3, characterized in that: The beam shaping module includes multiple gradient attenuation sheets, any one of which is arranged on the light-emitting side of the beam generating module and is perpendicular to the direction of the light path, and is used to adjust the transmittance of the extreme ultraviolet light beam; the multiple photodetectors correspond one-to-one to the multiple gradient attenuation sheets, respectively, and any one of the gradient attenuation sheets is used to adjust the transmittance of the local light beam collected by the corresponding photodetector.

5. An extreme ultraviolet lithography projection exposure method, applicable to the extreme ultraviolet lithography projection exposure optical system according to any one of claims 1 to 4, characterized in that: The steps include: The beam generating module generates an extreme ultraviolet beam; The beam shaping module adjusts the extreme ultraviolet beam; The light field uniformity adjustment module obtains the light intensity distribution data of the extreme ultraviolet light beam output by the beam shaping module; The light field uniformity adjustment module adjusts the output power of the light beam generation module according to the light intensity distribution data, so that the lowest light intensity in the extreme ultraviolet light beam intensity distribution data output by the beam shaping module after the power adjustment is not lower than the target light intensity; The light field uniformity adjustment module adjusts the transmittance of the gradient attenuation plate in the extreme ultraviolet beam shaping module according to the extreme ultraviolet beam intensity distribution data output by the beam shaping module after the power adjustment, so that the light intensity difference between any two positions in the extreme ultraviolet beam intensity distribution data output by the beam shaping module after the transmittance adjustment does not exceed the difference limit range; The beam projection module projects the extreme ultraviolet beam output by the beam shaping module after the transmittance is adjusted onto a target surface.

6. The extreme ultraviolet lithography projection exposure method according to claim 5, characterized in that: The method of adjusting the output power of the light beam generating module according to the light intensity distribution data so that the lowest light intensity in the extreme ultraviolet light beam intensity distribution data output by the light beam shaping module after the power adjustment is not lower than the target light intensity comprises the following steps: Extracting the lowest light intensity in the light intensity distribution data; Setting a target light intensity, and comparing the minimum light intensity with the target light intensity; The output power of the light beam generating module is adjusted according to a comparison result of the numerical values ​​of the minimum light intensity and the target light intensity.

7. The extreme ultraviolet lithography projection exposure method according to claim 6, characterized in that: The output power of the beam generating module satisfies the following adjustment rules: If the minimum light intensity is lower than the target light intensity, increasing the output power of the extreme ultraviolet light source module until the minimum light intensity in the extreme ultraviolet light beam intensity distribution data output by the beam shaping module after adjustment is not lower than the target light intensity; If the minimum light intensity is not lower than the target light intensity, the current output power of the extreme ultraviolet light source module is maintained.

8. The extreme ultraviolet lithography projection exposure method according to claim 5, characterized in that: The method comprises the following steps: adjusting the transmittance of the gradient attenuation plate in the extreme ultraviolet beam shaping module according to the extreme ultraviolet beam intensity distribution data output by the beam shaping module after the power adjustment, so that the light intensity difference between any two positions in the extreme ultraviolet beam intensity distribution data output by the beam shaping module after the transmittance adjustment does not exceed the difference limit range. Based on the intensity distribution data of the extreme ultraviolet light beam output by the beam shaping module after power adjustment, a uniform reference light intensity is obtained, wherein the uniform reference light intensity is a reference light intensity for measuring the uniformity of the light intensity distribution; Respectively obtaining the difference between each light intensity in the extreme ultraviolet light beam intensity distribution data output by the beam shaping module after power adjustment and the uniform reference light intensity; Setting a difference limit range, and setting the light intensity whose difference with the uniform reference light intensity does not meet the difference limit range as abnormal light intensity; The transmittance of the gradient attenuation plate corresponding to each abnormal light intensity position is adjusted respectively, so that the light intensity difference between any two positions in the extreme ultraviolet light beam intensity distribution data output by the beam shaping module after the transmittance adjustment does not exceed the difference limit range.

9. The extreme ultraviolet lithography projection exposure method according to claim 8, characterized in that: The transmittance of any gradient attenuation sheet in the EUV beam shaping module satisfies the following rules: If the difference between the abnormal light intensity and the uniform reference light intensity is lower than any light intensity within the difference limit range, the transmittance of the gradient attenuation sheet corresponding to the abnormal light intensity position is increased; If the difference between the abnormal light intensity and the uniform reference light intensity is higher than any light intensity within the difference limit range, the transmittance of the gradient attenuation sheet corresponding to the abnormal light intensity position is reduced.

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