Euv reflectivity detection apparatus and method for a mirror

Abstract

This specification provides an EUV reflectivity detection device and method for a mirror, wherein the method includes: determining the spectral transfer function of a reference optical path and a measurement optical path; calculating the full-spectrum signal and in-band signal received by the detectors of the reference optical path and the measurement optical path; calculating a spectral correction factor C(θ) based on the ratio of the proportion of in-band signals of the measurement optical path and the reference optical path; and calculating the equivalent in-band reflectivity R(θ) of the mirror under test based on the spectral correction factor C(θ).

Description

Technical Field

[0001] This document relates to the field of optical measurement technology, and in particular to an EUV reflectivity detection device and method for a mirror. Background Technology

[0002] Extreme ultraviolet (EUV) lithography is a core technology for achieving mass production of integrated circuits at technology nodes of 7nm and below. In EUV lithography systems, because extreme ultraviolet light (typically 13.5nm wavelength) is strongly absorbed by almost all materials, traditional transmission-type optical systems are no longer suitable. Instead, a reflective projection optical system based on Mo / Si multilayer mirrors is used. In this system, the exposure light must undergo multiple reflections to reach the silicon wafer surface; therefore, the absolute reflectivity of each EUV mirror directly determines the lithography machine's throughput.

[0003] Existing EUV reflectance testing technologies are mainly divided into two categories: The first type is the absolute reflectivity calibration method using synchrotron radiation sources. This method relies on large synchrotron radiation facilities (such as BESSY II, NSLS-II, and the Hefei Synchrotron Radiation Facility), utilizing the continuous spectrum emitted by these facilities. After dispersion by a monochromator, a highly collimated and stable EUV narrowband beam is obtained, and the ratio of incident light intensity to reflected light intensity is measured in an ultra-high vacuum environment. Although this method has extremely high measurement accuracy and can serve as an industry benchmark, its limitations include equipment scarcity, high operating costs, difficulty in scheduling testing sessions, and the inability to perform in-situ measurements. These limitations prevent it from meeting the practical needs of semiconductor wafer fabs or optical component manufacturers for rapid, online, and long-term performance evaluation of large batches of lenses.

[0004] The second category is testing solutions based on compact laboratory EUV light sources. These solutions typically use laser plasma (LPP) or gas discharge plasma (DPP) as the EUV light source, combined with Zr filters, multilayer mirrors, and a vacuum sample stage to construct the test optical path. Compared to synchrotron radiation, this type of system has advantages such as compact structure, lower cost, and ease of deployment, making it more suitable for routine testing of specific devices.

[0005] The solution addresses the issues of equipment size and cost, but the following problems still exist in practical industrial applications: (1) Measurement errors caused by light source instability: Compact EUV light sources generally suffer from pulse energy jitter and long-term power attenuation. Existing devices mostly use a single detector time-division measurement method, that is, first measuring the incident light intensity and then measuring the reflected light intensity. The instability of the light source will cause large fluctuations in the calculated reflectivity data, making it difficult to achieve high measurement accuracy. (2) Severe stray light interference: Industrial EUV lithography applications require spectral band power of 13.5 ± 0.135 nm, often expressed as "in-band power", that is, 13.5 nm 2% bandwidth. Plasma light sources generate a large amount of infrared, visible light and soft X-ray stray light. If the filtering system is not properly designed, stray light from EUV bands other than 2% bandwidth will directly cause inaccurate reflectivity measurements and affect detection accuracy. Summary of the Invention

[0006] The purpose of this invention is to provide an EUV reflectivity detection device and method for a reflector, aiming to solve the above-mentioned problems in the prior art.

[0007] This invention provides an EUV reflectivity detection device for a mirror, comprising: EUV light source module, used to emit EUV light; The beam shaping and splitting module includes a first aperture, a second aperture, a third aperture, and a fourth aperture. The reference optical path is configured with the first and third apertures, while the measurement optical path is configured with the second and fourth apertures. The light filtered by the Zr filter is incident on the first Mo / Si multilayer film mirror through the first aperture, reflected to the second Mo / Si multilayer film mirror, and then incident on the first detector through the third aperture. The light filtered by the Zr filter is incident on the third Mo / Si multilayer film mirror through the second aperture, reflected to the fourth Mo / Si multilayer film mirror, and then incident on the reflector of the sample mounting and angle scanning module through the fourth aperture. The spectral purification module includes one Zr filter and four Mo / Si multilayer film mirrors. The reference optical path is configured with a first and a second Mo / Si multilayer film mirror, while the measurement optical path includes a third and a fourth Mo / Si multilayer film mirror. The Zr filter is placed in front of the EUV light source module to filter the EUV light. The filtered light is incident on a first and a second aperture. The first Mo / Si multilayer film mirror receives the light from the first aperture and reflects it to the second Mo / Si multilayer film mirror. The second Mo / Si multilayer film mirror reflects the light to the third aperture. The third Mo / Si multilayer film mirror receives the light from the second aperture and reflects it to the fourth Mo / Si multilayer film mirror. The fourth Mo / Si multilayer film mirror reflects the light to the fourth aperture. The sample mounting and angle scanning module includes a vacuum multi-degree-of-freedom adjustment stage and a vacuum chamber set in the measurement optical path. The vacuum chamber is used to provide a vacuum environment for the vacuum multi-degree-of-freedom adjustment stage. The vacuum multi-degree-of-freedom adjustment stage is used to mount a reflector and provide multi-angle adjustment for the reflector. The reflector reflects the received light to a second detector. The detection module includes two detectors: a first detector is configured at the end of the reference optical path, and a second detector is configured at the end of the measurement optical path, for detecting the received light.

[0008] This invention provides a method for detecting the EUV reflectivity of a mirror, which can be used for high-precision detection of the EUV reflectivity of a mirror, and is used in the aforementioned EUV reflectivity detection device for the mirror. The method includes: Determine the spectral transfer functions of the reference optical path and the measurement optical path, and calculate the full-spectrum signal and in-band signal received by the detectors in the reference optical path and the measurement optical path; The spectral correction factor is calculated based on the ratio of the in-band signal proportions of the measurement optical path and the reference optical path. ; According to the spectral correction factor Calculate the equivalent in-band reflectivity of the mirror under test. .

[0009] This invention also provides an electronic device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program, when executed by the processor, implements the steps of the above-described method for detecting the EUV reflectivity of a reflector.

[0010] This invention also provides a computer-readable storage medium storing an information transmission implementation program, which, when executed by a processor, implements the steps of the above-described method for detecting the EUV reflectivity of a reflector.

[0011] By employing the embodiments of the present invention, the influence of light source instability on the measurement results is eliminated through a dual-optical-path configuration of a reference optical path and a measurement optical path; furthermore, by introducing an optical path spectral correction factor, the influence of stray light outside the 13.5 nm 2% bandwidth on the measurement results is reduced, thereby improving the measurement accuracy. Attached Figure Description

[0012] To more clearly illustrate the technical solutions in one or more embodiments of this specification or in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this specification. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 This is a schematic diagram of the EUV reflectivity detection device for a reflector according to an embodiment of the present invention; Figure 2 This is a flowchart of the EUV reflectivity detection method for a reflector according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the simulation results of the final detection spectral distribution of the reference optical path and the measurement optical path after spectral purification in an embodiment of the present invention; Figure 4 This is a schematic diagram illustrating the change of the relative deviation between the reflectance and the monochromatic reference value before and after spectral correction according to an embodiment of the present invention as a function of the incident angle; Figure 5 This is a schematic diagram of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0014] To enable those skilled in the art to better understand the technical solutions in one or more embodiments of this specification, the technical solutions in one or more embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this specification, and not all of the embodiments. Based on one or more embodiments of this specification, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of this document.

[0015] Device Examples According to an embodiment of the present invention, an EUV reflectivity detection device for a reflector is provided. Figure 1This is a schematic diagram of the EUV reflectivity detection device for a reflector according to an embodiment of the present invention, as shown below. Figure 1 As shown, the EUV reflectivity detection device for a reflector according to an embodiment of the present invention specifically includes: EUV light source module, used to emit EUV light; The beam shaping and splitting module includes a first aperture (i.e., aperture 1), a second aperture (i.e., aperture 2), a third aperture (i.e., aperture 3), and a fourth aperture (i.e., aperture 4). The reference optical path is configured with the first and third apertures, and the measurement optical path is configured with the second and fourth apertures. The light filtered by the Zr filter is incident on the first Mo / Si multilayer film mirror through the first aperture, reflected to the second Mo / Si multilayer film mirror, and then incident on the first detector through the third aperture. The light filtered by the Zr filter is incident on the third Mo / Si multilayer film mirror through the second aperture, reflected to the fourth Mo / Si multilayer film mirror, and then incident on the reflector of the sample mounting and angle scanning module through the fourth aperture. The spectral purification module includes one Zr filter and four Mo / Si multilayer film mirrors. The reference optical path is configured with a first Mo / Si multilayer film mirror (i.e., Mo / Si multilayer film mirror 1) and a second Mo / Si multilayer film mirror (i.e., Mo / Si multilayer film mirror 2). The measurement optical path is configured with a third Mo / Si multilayer film mirror (i.e., Mo / Si multilayer film mirror 3) and a fourth Mo / Si multilayer film mirror (i.e., Mo / Si multilayer film mirror 4). The Zr filter is placed in front of the EUV light source module to filter the EUV light, sending the filtered light to the first and second apertures. The first Mo / Si multilayer film mirror receives the light from the first aperture and reflects it to the second Mo / Si multilayer film mirror. The second Mo / Si multilayer film mirror reflects the light to the third aperture. The third Mo / Si multilayer film mirror receives the light from the second aperture and reflects it to the fourth Mo / Si multilayer film mirror. The fourth Mo / Si multilayer film mirror reflects the light to the fourth aperture. The sample mounting and angle scanning module includes a vacuum multi-degree-of-freedom adjustment stage and a vacuum chamber set in the measurement optical path. The vacuum chamber is used to provide a vacuum environment for the vacuum multi-degree-of-freedom adjustment stage. The vacuum multi-degree-of-freedom adjustment stage is used to mount a reflector and provide multi-angle adjustment for the reflector. The reflector reflects the received light to a second detector. The detection module includes two detectors: a first detector is configured at the end of the reference optical path, and a second detector is configured at the end of the measurement optical path, for detecting the received light.

[0016] from Figure 1 It can be seen that, as Figure 1As shown, the detection device is divided into a reference optical path and a measurement optical path, comprising one EUV light source, one Zr filter, four apertures, four Mo / Si multilayer mirrors, one vacuum multi-degree-of-freedom adjustment stage, one vacuum chamber, and two detectors. It is mainly divided into the following functional modules: (1) EUV light source module: Usually one DPP or LPP light source is used to emit EUV light.

[0017] (2) Beam shaping and beam splitting module: It consists of 4 apertures, with 2 in the reference optical path and 2 in the measurement optical path.

[0018] (3) Spectral purification module: It consists of 1 Zr filter and 4 Mo / Si multilayer film mirrors, with 2 Mo / Si multilayer film mirrors configured in the reference optical path and the measurement optical path.

[0019] (4) Sample mounting and angle scanning module: A vacuum multi-degree-of-freedom adjustment stage and a vacuum chamber are set in the measurement optical path.

[0020] (5) Detection module: It consists of two detectors, with one detector at the end of the reference optical path and one at the end of the measurement optical path.

[0021] The EUV light source generates broadband EUV radiation centered at 13.5 nm. This radiation first undergoes preliminary spectral purification via a Zr thin-film filter, suppressing out-of-band radiation in the visible and infrared bands while simultaneously preventing plasma debris from contaminating and damaging downstream optical components. The beam after the Zr filter passes through a pair of apertures (aperture 1 and aperture 2) arranged symmetrically about the optical axis for initial intensity tuning and beam shaping. The beam is then split into two independent channels: a reference path and a measurement path. Two Mo / Si multilayer mirrors (Mo / Si mirror 1 and Mo / Si mirror 2) utilize their narrowband high reflectivity at specific incident angles to perform secondary spectral compression on the passing EUV radiation, further concentrating the photon flux into the in-band region around 13.5 nm. Through the combined filtering effect of the Zr filter and the two Mo / Si multilayer mirrors, effective out-of-band radiation suppression and spectral bandwidth narrowing are achieved without using a grating monochromator, resulting in a quasi-narrowband EUV beam suitable for reflectivity measurement. Each optical path is also equipped with a second-stage aperture (aperture 3 and aperture 4) to further adjust the light intensity and improve the spatial uniformity of the beam. The mirror under test is mounted on a vacuum multi-degree-of-freedom adjustment stage in the vacuum cavity at the end of the measurement optical path. By adjusting the pitch angle of this stage, continuous scanning of the incident angle within a certain range is achieved. A detector is configured at the end of each of the two optical paths to convert the EUV radiation signal into an electrical signal. The signals from the two detectors are acquired synchronously, and the influence of light source power fluctuations is corrected by calculating the signal ratio.

[0022] Method Implementation Examples According to an embodiment of the present invention, a method for detecting the EUV reflectivity of a mirror is provided, which is used in the aforementioned EUV reflectivity detection device for the mirror. Figure 2 This is a flowchart of the EUV reflectivity detection method for a reflector according to an embodiment of the present invention, as follows: Figure 2 As shown, the EUV reflectivity detection method for a reflector according to an embodiment of the present invention specifically includes: Step S201: Determine the spectral transfer functions of the reference optical path and the measurement optical path, and calculate the full-spectrum signal and in-band signal received by the detectors of the reference optical path and the measurement optical path; Specifically, it includes: Calculate the spectral transfer function of the reference optical path according to Formula 1. : Formula 1; in, The spectral transmittance of the Zr filter is... The reflectivities of the first and second Mo / Si multilayer mirrors are respectively. When the reflector is at the angle of incidence The location has spectral reflectance Then, calculate the spectral transfer function of the measurement optical path according to Formula 2. for: Formula 2.

[0023] Let the spectral power density distribution of EUV light be... The detector's spectral responsivity is Then, the full-spectrum signals received by the detectors in the reference optical path and the measurement optical path are calculated according to formulas 3 and 4: Formula 3; Formula 4; in, For the effective spectral range of the system, The full-spectrum signal recorded by the detector in the reference optical path. The detector in the measurement optical path records the full-spectrum signal after reflection by the mirror.

[0024] Calculate the effective signals of the reference optical path and the measurement optical path within this in-band window using formulas 5 and 6: Formula 5; Formula 6; in , These are the upper and lower limits of the in-band wavelength range. The effective signal for the reference optical path; To measure the effective signal of the optical path.

[0025] Step S202: Calculate the spectral correction factor based on the ratio of the in-band signal proportions of the measurement optical path and the reference optical path. Specifically, it includes: Calculate the spectral correction factor according to Formula 7. : Formula 7.

[0026] in, The calculation requires knowledge of the spectral characteristics of each component of the system. , , , R(λ,θ) and R(λ,θ) were measured uniformly using a spectrometer. It is obtained through spectral responsivity calibration.

[0027] Step S203, according to the spectral correction factor Calculate the equivalent in-band reflectivity of the mirror under test. Specifically, this includes: Using spectral correction factors The equivalent in-band reflectivity of the mirror under test is calculated according to Formula 8. : Formula 8.

[0028] The following is a detailed description in conjunction with the accompanying drawings.

[0029] The measurement procedure of the detection device is as follows: At each incident angle to be measured on the reflector, the detector in the reference optical path first records the reference signal. It reflects the current power of the light source and the transmission efficiency of the optical path; at the same time, the detector in the measurement optical path records the signal reflected by the mirror. The ratio of the two signals This eliminates the interference from light source power fluctuations. However, due to the wide spectral bandwidth of the light source, the above ratio is not strictly equal to the reflectance within the 13.5nm 2% bandwidth, but rather a weighted integral of the reflectance over a certain spectral range. To correct the broadband integral measurement to an equivalent in-band reflectance, a spectral correction factor needs to be introduced.

[0030] Based on the well-defined optical path configuration and spectral characteristics of each component in the detection device, a complete system of spectral correction formulas is established. Considering the reference optical path, which does not include the mirror under test, the beam passes sequentially through a Zr filter and two Mo / Si multilayer mirrors before reaching the detector. The spectral transfer function of the reference optical path is... It can be represented as: (1) in The spectral transmittance of the Zr filter is... These are the reflectivities of the first and second Mo / Si multilayer mirrors, respectively.

[0031] For the measurement optical path, after the light beam passes through the Zr filter and two Mo / Si multilayer mirrors, it still needs to illuminate the surface of the mirror under test and be reflected by it. When the mirror is at the incident angle... The location has spectral reflectance When measuring the spectral transfer function of the optical path for: (2) Comparing equations (1) and (2), it can be seen that the additional spectral transfer factor of the measuring optical path compared to the reference optical path is exactly the spectral reflectance of the mirror under test. This is the design basis for the dual-path ratio measurement scheme.

[0032] Let the spectral power density distribution of the EUV light source be... The detector's spectral responsivity is The signals received by the detectors in the reference optical path and the measurement optical path are respectively: (3) (4) in For the effective spectral range of the system, According to the generally accepted definition in the EUVL field, a center wavelength of 13.5 nm is considered... The 1% range (i.e., a 2% bandwidth window of 0.27 nm from 13.365 nm to 13.635 nm) is defined as the in-band radiation region. The effective signals of the reference and measurement optical paths within this in-band window are as follows: (5) (6) in , These are the upper and lower limits of the in-band wavelength range.

[0033] It can be seen from equations (3) to (6) that the full spectrum signal , With in-band signal , The differences depend on the relative contribution ratio of out-of-band radiation in each optical path. In actual measurements, the detector can directly record the full-spectrum signal. and And in-band signal and It cannot be directly measured. To establish a quantitative link between the measurable full-spectrum signal and the desired in-band reflectance, a spectral correction factor is introduced. .

[0034] Spectral correction factor Defined as the ratio of the in-band signal percentages of the measurement optical path and the reference optical path: (7) From a physical perspective, Characterizes the situation at a given incident angle The spectral characteristics of the reflectivity of the mirror under test modulate the in-band signal ratio between the reference and measurement optical paths. When the reflectivity of the mirror has different weightings in the in-band and out-of-band bands, the in-band signal ratio of the measurement optical path differs from that of the reference optical path. This difference needs to be quantitatively compensated. If the reflectivity of the mirror is constant across the entire spectrum (i.e.... ),but No correction is needed. However, for practical multilayer mirrors, their reflectivity exhibits a narrow band characteristic. There are significant differences between inside and outside the band, therefore It typically deviates from 1, and its value varies with the angle of incidence.

[0035] Using spectral correction factors The equivalent in-band reflectivity of the mirror under test It can be represented as: (8) Equation (8) is the core calculation formula for reflectivity measurement in this detection device. The second term on its right-hand side... It is the ratio of the full-spectrum signal that the detector can directly measure, and the influence of light source power fluctuations has been eliminated through the dual-optical-path scheme; the first item This is a spectral correction factor that maps the full-spectrum ratio to an equivalent in-band reflectance. The calculation requires knowledge of the spectral characteristics of each component of the system. , , , , and R(λ,θ)). , , , R(λ,θ) and R(λ,θ) can be uniformly measured using a spectrometer. It can be obtained through spectral response calibration, and then calculated using equation (7).

[0036] Figure 3 The simulation results of the final detection spectral distribution of the reference and measurement optical paths are presented after processing with the complete spectral purification chain. Figure 3 The shaded area indicates the 2% in-band window (13.365–13.635 nm) at 13.5 nm ± 1%, where S represents S-polarized light and M represents the average of S-polarized and P-polarized light. The following characteristics can be observed: (1) After the combined filtering of Zr filter and Mo / Si multilayer film mirror, the detection signal spectra of both optical paths are highly concentrated in the in-band region around 13.5 nm, and the out-of-band radiation is effectively suppressed.

[0037] (2) The in-band signal accounts for about 50%–60% of the total detection signal, indicating that the spectral purification scheme achieves effective spectral bandwidth control without using a grating monochromator.

[0038] (3) There is a difference in the spectral shape between the reference optical path and the measurement optical path. The spectral distribution of the measurement optical path is also affected by the modulation effect of the reflectivity of the mirror, which causes its spectral shape to change with the incident angle. This difference is the physical reason for introducing the spectral correction factor.

[0039] (4) Limited spectral tail distribution can still be observed outside the 2% in-band window. Although these residual out-of-band contributions have been greatly suppressed by cascade filtering, they have not been completely eliminated and need to be numerically compensated by spectral correction factors.

[0040] Based on the confirmation of the effectiveness of the spectral purification protocol, the spectral correction factor was further evaluated. The effect on improving measurement accuracy. The evaluation method is as follows: the 13.5nm monochromatic reflectance calculated based on the transfer matrix method (TMM) is used as the theoretical design reference value, and the equivalent in-band reflectance obtained after spectral correction using equation (8) is used as the simulated measurement value. The relative deviation between the two is calculated to quantify the accuracy of spectral correction.

[0041] Specifically, for 13 sampling points with different incident angles within the common working angle range of the reflector, the reflectivity and relative deviation before and after correction were calculated. The relative deviation is defined as: (9) in The design reflectivity of the TMM is calculated under monochromatic conditions at 13.5 nm. The equivalent reflectance after spectral correction is calculated using equation (8). This directly reflects the accuracy of the spectral correction algorithm in tracing broadband integral measurements back to monochromatic reflectance.

[0042] Figure 4Simulation results are presented showing the relative deviation between the reflectance before and after spectral correction and the monochromatic reference value within a common operating incident angle range. The results indicate that without spectral correction, the calculation of the mirror reflectance from the detector signal will have a large error; however, the relative deviation between the equivalent reflectance after spectral correction and the monochromatic reference value is controlled at a low level across the entire angle range.

[0043] Device Example 2 This invention provides an electronic device, such as... Figure 5 As shown, it includes: a memory 50, a processor 52, and a computer program stored in the memory 50 and executable on the processor 52, wherein the computer program, when executed by the processor 52, performs the steps as described in the method embodiment.

[0044] Device Example 3 This invention provides a computer-readable storage medium storing an information transmission implementation program, which, when executed by a processor 52, performs the steps described in the method embodiment.

[0045] The computer-readable storage media described in this embodiment include, but are not limited to, ROM, RAM, disk, or optical disk.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A device for detecting the EUV reflectivity of a mirror, characterized in that, include: EUV light source module, used to emit EUV light; The beam shaping and splitting module includes a first aperture, a second aperture, a third aperture, and a fourth aperture. The reference optical path is configured with the first and third apertures, while the measurement optical path is configured with the second and fourth apertures. The light filtered by the Zr filter is incident on the first Mo / Si multilayer film mirror through the first aperture, reflected to the second Mo / Si multilayer film mirror, and then incident on the first detector through the third aperture. The light filtered by the Zr filter is incident on the third Mo / Si multilayer film mirror through the second aperture, reflected to the fourth Mo / Si multilayer film mirror, and then incident on the reflector of the sample mounting and angle scanning module through the fourth aperture. The spectral purification module includes one Zr filter and four Mo / Si multilayer film mirrors. The reference optical path is configured with a first and a second Mo / Si multilayer film mirror, while the measurement optical path includes a third and a fourth Mo / Si multilayer film mirror. The Zr filter is placed in front of the EUV light source module to filter the EUV light. The filtered light is incident on a first and a second aperture. The first Mo / Si multilayer film mirror receives the light from the first aperture and reflects it to the second Mo / Si multilayer film mirror. The second Mo / Si multilayer film mirror reflects the light to the third aperture. The third Mo / Si multilayer film mirror receives the light from the second aperture and reflects it to the fourth Mo / Si multilayer film mirror. The fourth Mo / Si multilayer film mirror reflects the light to the fourth aperture. The sample mounting and angle scanning module includes a vacuum multi-degree-of-freedom adjustment stage and a vacuum chamber set in the measurement optical path. The vacuum chamber is used to provide a vacuum environment for the vacuum multi-degree-of-freedom adjustment stage. The vacuum multi-degree-of-freedom adjustment stage is used to mount a reflector and provide multi-angle adjustment for the reflector. The reflector reflects the received light to a second detector. The detection module includes two detectors: a first detector is configured at the end of the reference optical path, and a second detector is configured at the end of the measurement optical path, for detecting the received light.

2. A method for detecting the EUV reflectivity of a mirror, characterized in that, The EUV reflectivity detection device for the reflector according to claim 1, wherein the method specifically includes: Determine the spectral transfer functions of the reference optical path and the measurement optical path, and calculate the full-spectrum signal and in-band signal received by the detectors in the reference optical path and the measurement optical path; The spectral correction factor is calculated based on the ratio of the in-band signal proportions of the measurement optical path and the reference optical path. ; According to the spectral correction factor Calculate the equivalent in-band reflectivity of the mirror under test. .

3. The method according to claim 2, characterized in that, Determining the spectral transfer functions of the reference and measurement optical paths specifically includes: Calculate the spectral transfer function of the reference optical path according to Formula 1. : Official 1; in, The spectral transmittance of the Zr filter is... The reflectivities of the first and second Mo / Si multilayer mirrors are respectively. When the reflector is at the angle of incidence The location has spectral reflectance Then, calculate the spectral transfer function of the measurement optical path according to Formula 2. for: Official 2.

4. The method according to claim 3, characterized in that, The full-spectrum signal received by the detectors in the reference and measurement optical paths specifically includes: Let the spectral power density distribution of EUV light be... The detector's spectral responsivity is Then, the full-spectrum signals received by the detectors in the reference optical path and the measurement optical path are calculated according to formulas 3 and 4: Official 3; Official 4; in, For the effective spectral range of the system, The full-spectrum signal recorded by the detector in the reference optical path. The detector in the measurement optical path records the full-spectrum signal after reflection by the mirror.

5. The method according to claim 4, characterized in that, The calculation of the in-band signals received by the detectors in the reference and measurement optical paths specifically includes: Calculate the effective signals of the reference optical path and the measurement optical path within this in-band window using formulas 5 and 6: Official 5; Official 6; in , These are the upper and lower limits of the in-band wavelength range. The effective signal for the reference optical path; To measure the effective signal of the optical path.

6. The method according to claim 5, characterized in that, The spectral correction factor is calculated based on the ratio of the in-band signal proportions of the measurement optical path and the reference optical path. Specifically, it includes: Calculate the spectral correction factor according to Formula 7. : Official 7.

7. The method according to claim 6, characterized in that, According to the spectral correction factor Calculate the equivalent in-band reflectivity of the mirror under test. Specifically, it includes: Using spectral correction factors The equivalent in-band reflectivity of the mirror under test is calculated according to Formula 8. : Official 8.

8. The method according to claim 7, characterized in that, The calculation requires knowledge of the spectral characteristics of each component of the system. , , , R(λ,θ) and R(λ,θ) were measured uniformly using a spectrometer. It is obtained through spectral responsivity calibration.

9. An electronic device, characterized in that, include: The memory, the processor, and the computer program stored in the memory and executable on the processor, wherein the computer program, when executed by the processor, implements the steps of the EUV reflectivity detection method for a mirror as described in any one of claims 2 to 8.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores an implementation program for information transmission, which, when executed by a processor, implements the steps of the EUV reflectivity detection method for a mirror as described in any one of claims 2 to 8.

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