A reflectance test system and a reflectance contrast verification method

Abstract

The present disclosure provides a reflectivity test system and a reflectivity contrast verification method. The system comprises, in sequence along an optical path, a light source system, a collection mirror chamber, and a sample test chamber. The collection mirror chamber is provided with a focusing collection mirror, and the sample test chamber is provided with a filter, an energy normalization structure, a first energy detector, a displacement table, and a second energy detector. The reflectivity contrast verification method is used to verify the test accuracy of the reflectivity test system. Compared with the prior art, the reflectivity test system provided by the present application is simple in structure, and the accuracy of the test results can be verified and improved by the reflectivity contrast verification method provided by the present application. Therefore, the reflectivity test accuracy can be ensured while miniaturizing the reflectivity test system.

Description

Technical Field

[0001] This disclosure relates to the field of optical measurement technology, specifically to a reflectance testing system and a reflectance comparison and verification method. Background Technology

[0002] With the development of photolithography technology, higher requirements have been placed on the performance testing of optical components. Reflectivity is a key parameter of optical component performance, and changes in reflectivity have a significant impact on light transmission and can even directly affect photolithography yield. Therefore, high-precision reflectivity testing is a fundamental support for the development of photolithography technology.

[0003] Internationally, many institutions have built high-precision reflectivity testing devices based on synchrotron radiation sources, greatly promoting the development of photolithography technology. However, experimental research requires frequent reflectivity testing, so small-scale reflectivity testing devices based on small plasma sources such as DPP (Discharge Produced Plasma) and LPP (Laser Produced Plasma) have also been developed internationally. Compared to reflectivity testing devices based on synchrotron radiation sources, these small-scale devices are smaller, have lower maintenance costs, and are more flexible in placement, making them more suitable for routine laboratory research. However, existing small-scale reflectivity testing devices often have low reflectivity measurement accuracy, and how to verify the accuracy of these devices is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0004] The purpose of this disclosure is to provide a reflectivity testing system and a reflectivity comparison and verification method to improve the accuracy of reflectivity testing.

[0005] This disclosure provides a reflectivity testing system, including:

[0006] A light source system, a collection mirror chamber, and a sample testing chamber are arranged sequentially along the optical path; the collection mirror chamber is equipped with a focusing collection mirror, and the sample testing chamber is equipped with a filter, an energy normalization structure, a first energy detector, a displacement stage, and a second energy detector.

[0007] The light source system is used to generate an irradiation source, the light beam emitted by which is a broadband light with a certain divergence angle;

[0008] The focusing and collecting mirror is used to reflect and focus the light beam emitted by the irradiation source, with the focal point located in the sample testing chamber and between the filter and the energy normalization structure;

[0009] In the sample testing chamber, the light beam reflected and focused by the focusing collecting mirror is filtered by the filter and then focused at the focal point. After passing through the focal point, the light beam continues to propagate into the energy normalization structure. The energy normalization structure extracts two beams of light, namely a test beam and a monitoring beam. The monitoring beam enters the first energy detector, and the test beam is incident on the surface of the sample to be tested. After being reflected by the sample surface, it enters the second energy detector.

[0010] The displacement stage is used to mount the sample to be tested and the second energy detector, and can adjust the test position of the sample and the detection position of the second energy detector.

[0011] In one possible implementation, the surfaces of the focusing and collecting mirror, the filter, the first energy detector, and the second energy detector are coated with a filter film to obtain a light beam with a preset wavelength and a preset bandwidth.

[0012] In one possible implementation, the system further includes:

[0013] The vacuum pump unit is used to evacuate the entire reflectivity testing system.

[0014] In one possible implementation, the system further includes:

[0015] A vacuum gauge is used to monitor the vacuum level of the entire reflectivity testing system.

[0016] In one possible implementation, the light source system employs an LPP light source or a DPP light source.

[0017] This disclosure also provides a reflectance testing method, based on the reflectance testing system described in the above embodiments, the method comprising:

[0018] The light source system is activated. Before the sample reflectivity test, the sample to be tested is removed from the optical path, and the energy E of the monitoring beam is detected using the first energy detector. 9i The energy E of the test beam was detected using a second energy detector. 11i ;

[0019] During the sample reflectivity test, the sample to be tested is adjusted to a preset position in the optical path, the incident angle is set to θ, and the second energy detector is adjusted to a position of 2θ. At this time, the energy E of the reflected light from the sample is detected using the second energy detector. 11r The energy E of the monitoring beam is detected using the first energy detector. 9r ;

[0020] The energy normalization calibration factor F = E was calculated. 9r / E 9i ;

[0021] Using the formula R=E 11r / (E 11i The sample reflectance R is calculated using *F).

[0022] This disclosure also provides a reflectance comparison verification method for use with the reflectance testing system described in the above embodiments, the method comprising:

[0023] The standard reflectivity testing apparatus used for comparative verification is determined. This standard reflectivity testing apparatus uses a synchrotron radiation source and the test beam is highly monochromatic s-polarized light. The test beam of the reflectivity testing system to be verified is non-monochromatic unpolarized light.

[0024] The reflectance spectrum R of the sample under unpolarized light was obtained using the standard reflectance testing device. n (λ), where λ represents the wavelength;

[0025] Calculate the test beam spectrum S of the reflectivity testing system to be verified. in (λ)=S(λ)×R(λ)×T(λ); where S(λ) represents the radiation spectrum distribution of the irradiation source generated by the light source system, R(λ) represents the reflection spectrum of the focusing and collecting mirror, and T(λ) represents the transmission spectrum of the filter.

[0026] Calculate the reflected light spectrum S of the sample in the reflectivity testing system to be verified. r (λ)=S in (λ)

[0027] ×R n (λ);

[0028] Calculate the theoretical reflectance of the sample Among them, the spectrum of the test beam incident on the sample, S in (λ) Wavelength range is between λ1nm and λ2nm, S d (λ) represents the spectral response spectrum of the energy detector;

[0029] The reflectance R of the sample was obtained based on the reflectance testing system to be verified. t =E 11r / (E 11i *F);

[0030] The theoretical reflectance R of the comparison sample theory and the experimentally measured reflectance R t The difference is used to verify the reflectivity comparison.

[0031] In one possible implementation, the standard reflectance testing device is used to obtain the reflectance spectrum R of the sample under unpolarized light. n(λ), including:

[0032] The reflectance of the sample is tested using the standard reflectance testing device, and the reflectance R of the sample under unpolarized light is calculated based on the reflectance of the sample under two different degrees of polarization (s-polarized light). n =

[0033] (R s +R p ) / 2; where R s R represents the reflectivity under s-polarized light. p This represents the reflectivity under p-polarized light;

[0034] The reflectance spectrum R of the sample under unpolarized light was obtained by scanning the incident light wavelength. n (λ).

[0035] The advantages of this disclosure compared to the prior art are:

[0036] The reflectivity testing system disclosed herein includes: a light source system, a collection mirror chamber, and a sample testing chamber arranged sequentially along the optical path; a focusing collection mirror is disposed in the collection mirror chamber, and a filter, an energy normalization structure, a first energy detector, a displacement stage, and a second energy detector are disposed in the sample testing chamber. Compared with the prior art, the reflectivity testing system provided in this application has a simple structure and can verify and improve the accuracy of the test results through the reflectivity comparison verification method provided in this application. Therefore, it can ensure the accuracy of reflectivity testing while miniaturizing the reflectivity testing system. Attached Figure Description

[0037] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this disclosure. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0038] Figure 1 A schematic diagram of the structure of a reflectivity testing system provided in this disclosure is shown;

[0039] Figure 2 A schematic diagram of another reflectivity testing system provided in this disclosure is shown;

[0040] Figure 3 A schematic diagram of a reflectivity comparison verification process provided in this disclosure is shown. Detailed Implementation

[0041] Embodiments of the present disclosure will now be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the disclosure. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concepts of the present disclosure.

[0042] The accompanying drawings illustrate various structural schematics according to embodiments of the present disclosure. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0043] In the context of this disclosure, when a layer / element is referred to as being "above" another layer / element, the layer / element may be directly above the other layer / element, or there may be an intermediate layer / element between them. Additionally, if a layer / element is "above" another layer / element in one orientation, then when the orientation is reversed, the layer / element may be "below" the other layer / element.

[0044] To address the problems existing in the prior art, this disclosure provides a reflectivity testing system and method, and a reflectivity comparison and verification method, which will be described below in conjunction with the accompanying drawings.

[0045] Figure 1 A schematic diagram of the structure of a reflectivity testing system provided in an embodiment of this application is shown, as follows: Figure 1 As shown, the reflectivity testing system includes: a light source system 1, a collection mirror chamber 2, and a sample testing chamber 3 arranged sequentially along the optical path; the light source system 1 generates an irradiation source 1, the collection mirror chamber 2 is equipped with a focusing collection mirror 5, and the sample testing chamber 3 is equipped with a filter 6, a focal point 7, an energy normalization structure 8, a first energy detector 9, a sample to be tested 10, a displacement stage (not shown), and a second energy detector 11.

[0046] Figure 2 This paper shows a schematic diagram of another reflectivity testing system provided in an embodiment of this application. Figure 2 The reflectivity testing system shown is Figure 1 The difference between the reflectivity testing systems shown is: Figure 1 The focusing and collecting lens 5 is a focusing and collecting lens for small-angle incident light. Figure 2 The focusing and collecting lens 5 is a focusing and collecting lens for large-angle incident light.

[0047] The light source system 1 is used to generate an irradiation source 2. The light beam emitted by the irradiation source 2 is a broadband light with a certain divergence angle. The divergent light beam is reflected and focused after being incident on the focusing and collecting mirror 5. Specifically, the light source system can use various small plasma light sources such as LPP light sources or DPP light sources, which can make the reflectivity testing system miniaturized.

[0048] The focusing and collecting mirror 5 is used to reflect and focus the light beam emitted by the irradiation source 4. The focal point 7 is located in the sample testing chamber 3 and between the filter 6 and the energy normalization structure 8. The filter 6 is used to filter out long-wavelength light.

[0049] The displacement stage is used to mount the sample 10 to be tested and the second energy detector 11, and can adjust the test position of the sample 10 and the detection position of the second energy detector 11.

[0050] In the sample testing chamber 3, the light beam reflected and focused by the focusing collecting mirror 5 is filtered by the filter 6 and then focused at the focal point 7. After passing through the focal point 7, the light beam continues to propagate into the energy normalization structure 8. The energy normalization structure 8 extracts two beams of light, namely a test beam and a monitoring beam. The monitoring beam enters the first energy detector 9, and the test beam is incident on the surface of the sample 10 to be tested. After being reflected by the sample surface, it enters the second energy detector 11.

[0051] As can be seen, in this application, two beams of light are extracted through the energy normalization structure 8 for testing and energy monitoring, respectively. The test beam is incident on the surface of the sample 10 under test, and its reflected light energy is detected by the second energy detector 11, thereby testing the reflectivity of the sample. The monitoring beam is detected by the first energy detector 9, which is used to monitor the energy fluctuation of the light source in real time, so as to calibrate the energy fluctuation of the test beam and reduce the influence of incident light energy fluctuation on reflectivity testing. The sample 10 under test and the second energy detector 11 are mounted on a precision displacement stage, which can realize the adjustment of the test position of the sample 10 under test, as well as the linkage adjustment of the incident angle θ of the test beam and the reflected light angle 2θ.

[0052] In some embodiments, the surfaces of the focusing and collecting mirror 5, the filter 6, the first energy detector 9, and the second energy detector 11 are coated with a filter film to obtain a light beam with a preset wavelength and a preset bandwidth. For example, obtaining a light beam with a wavelength of 13.5 nm and a bandwidth of 4% allows for the testing of the reflectance of a sample at 13.5 nm (4% bandwidth). A light beam with a wavelength of 13.5 nm belongs to the extreme ultraviolet (EUV) band. Light in this band has very high energy because, according to the photon energy formula, the shorter the wavelength, the higher the photon energy. A 4% bandwidth means that the wavelength of the light beam is not a single 13.5 nm, but rather within a certain range. Therefore, the reflectance testing system of this application can provide high-precision EUV reflectance testing.

[0053] In some embodiments, the reflectivity testing system of this application further includes a vacuum pump group, which is used to evacuate the entire reflectivity testing system.

[0054] In some embodiments, the reflectivity testing system of this application further includes a vacuum gauge, which is used to monitor the vacuum level of the entire reflectivity testing system to ensure that the vacuum level meets the testing requirements.

[0055] This application also provides a reflectivity testing method based on the aforementioned reflectivity testing system, which can achieve high-precision testing of the reflectivity of optical components. The reflectivity testing method includes:

[0056] Before testing the reflectivity of the sample, load the sample to be tested 10. Specifically, the vacuum pump group can be started to evacuate the entire reflectivity testing system, and the vacuum gauge can be started to monitor the air pressure in each chamber of the entire reflectivity testing system. When the system vacuum reaches the required vacuum level, the light source system 1 can be started.

[0057] Start the light source system 1. Before testing the sample reflectivity, remove the sample to be tested from the optical path and use the first energy detector to detect the energy E of the monitoring beam. 9i The energy E of the test beam was detected using a second energy detector. 11i .

[0058] During the sample reflectivity test, the sample 10 to be tested is adjusted to a preset position (x, y, z) in the optical path, the incident angle of the test beam is set to θ, and the second energy detector 11 is adjusted to the position of 2θ. At this time, the energy E of the reflected light from the sample is detected by the second energy detector 11. 11r The energy E of the monitoring beam is detected using the first energy detector 9. 9r Then, the energy normalization calibration factor F = E is obtained through calculation. 9r / E 9i Then E 11i *F represents the energy of the calibrated test beam.

[0059] Finally, using the formula R=E 11r / (E 11i The reflectance R of the sample is calculated using *F), and the reflectance R is the calibrated reflectance.

[0060] To verify the reflectivity testing accuracy of the aforementioned reflectivity testing system and to continuously improve the system based on the verification results, this application also provides a reflectivity comparison verification method, the method comprising:

[0061] Step 1: Determine the standard reflectivity testing device used for comparison and verification. This standard reflectivity testing device uses a synchrotron radiation source and the test beam is highly monochromatic s-polarized light; the test beam of the reflectivity testing system to be verified is non-monochromatic unpolarized light.

[0062] Because the reflectivity testing system of this application lacks a monochromator, it cannot scan the incident spectrum to obtain the reflectance spectrum showing the variation of reflectance with incident wavelength. In the reflectivity testing system of this application, a light beam with a wavelength of 13.5 nm and a bandwidth of 4% is obtained through the focusing collecting mirror 5, the filter 6, and the filter films deposited on the surfaces of the second energy detector 11 and the first energy detector 9. This allows for the testing of the reflectivity of the sample at 13.5 nm (4% bandwidth). To evaluate the accuracy of the reflectivity test, it is necessary to compare and verify the results with those of a standard reflectivity testing device, which is internationally recognized as having relatively accurate results. The reflectivity testing system proposed in this application uses a DPP light source as an example, where the test beam is non-monochromatic, unpolarized light. In contrast, the standard reflectivity testing device uses a synchrotron radiation source, and the test beam is highly monochromatic, s-polarized light. This application proposes the aforementioned reflectivity comparison and verification method to address the differences in the test light source parameters of the reflectivity testing devices.

[0063] Step 2: Obtain the reflectance spectrum R of the sample under unpolarized light using the standard reflectance testing device. n (λ), where λ represents the wavelength;

[0064] A reflectance spectrum is a curve showing how the reflectance of a material or optical element to different wavelengths of light changes with wavelength. It describes how the degree to which light is reflected after it strikes an object's surface changes with wavelength within a specific wavelength range.

[0065] Specifically, the reflectance of the sample is tested using the standard reflectance testing device, and the reflectance R of the sample under unpolarized light is calculated based on the reflectance of the sample under two different degrees of polarization (s-polarized light). n =(R s +R p ) / 2; where R s R represents the reflectivity under s-polarized light. pThe reflectance is expressed as p-polarized light; the reflectance spectrum R of the sample under unpolarized light is obtained by scanning the incident light wavelength. n (λ).

[0066] This application uses s-polarized light tests with polarization degrees of 98% and 50% as examples for illustration. Assume R... s and R p The reflectance of sample 10 under s-polarized light and p-polarized light are respectively, I s To test the intensity of the s-polarization component in the beam, I p To test the intensity of the p-polarized component in the light beam, I = I s +I p To test the total light intensity of the beam.

[0067] When using s-polarized light with a polarization degree of 98% for testing, I s =0.99I,I p =0.01I, then:

[0068] I s ×R s +I p ×R p =R 98％ ×I, that is: 0.99×R s +0.01×R p =R 98％ (Formula 1); When using s-polarized light with a polarization degree of 50% for testing, I s =0.75I, I p =0.25I, then:

[0069] I s ×R s +I s ×R p =R 50％ ×I, that is: 0.75×R s +0.25×R p =R 50％ (Formula 2).

[0070] The reflectance R of the sample 10 under s-polarized light with polarization degrees of 98% and 50% was measured on a standard reflectance testing apparatus. 98％ and R 50％ R can be calculated using formulas 1 and 2. s and R p Therefore, the reflectance R of the sample 10 under unpolarized light can be calculated. n =(R s +R p ) / 2. The reflectance spectrum R of the sample 10 can be obtained by scanning the incident light wavelength.n (λ).

[0071] Step 3: Calculate the test beam spectrum S of the reflectivity testing system to be verified. in (λ)=S(λ)×R(λ)×T(λ); where S(λ) represents the radiation spectrum distribution of the irradiation source 4 generated by the light source system, R(λ) represents the reflection spectrum of the focusing and collecting mirror 5, and T(λ) represents the transmission spectrum of the filter 6;

[0072] Specifically, the radiation spectral distribution S(λ) of the irradiation source 4, the reflection spectrum R(λ) under unpolarized light obtained by the focusing and collecting mirror 5, and the transmission spectrum T(λ) of the filter 6 are then used to obtain the spectrum S of the test beam under non-monochromatic light for reflectivity testing. in (λ)=S(λ)×R(λ)×T(λ).

[0073] Step 4: Calculate the reflected light spectrum S of the sample in the reflectivity testing system to be verified. r (λ)=S in (λ)×R n (λ);

[0074] Specifically, the second step yields the reflectance spectrum of sample 10 under unpolarized light as R. n (λ), the reflectance test beam spectrum of the irradiation source 4 after passing through the focusing and collecting mirror 5 and the filter 6, obtained from the third step, is S. in (λ), then the second energy detector 11 detects the reflected light spectrum S of the sample 10 under non-monochromatic light. r (λ)=S in (λ)×R n (λ).

[0075] Step 5: Calculate the theoretical reflectance of the sample. Among them, the spectrum of the test beam incident on the sample, S in (λ) Wavelength range is between λ1nm and λ2nm, S d (λ) represents the spectral response spectrum of the energy detector;

[0076] Specifically, the broadband irradiation light emitted by the irradiation source 4 passes through the focusing and collecting mirror 5 and the filter 6, and then the test beam spectrum S is incident on the sample 10 to be tested. in (λ) The wavelength range is between λ1nm and λ2nm; spectral energy outside this range has been filtered out. The reflectance spectrum of the test sample 10, measured and calculated using a standard reflectance testing device based on high monochromaticity, under unpolarized light in the wavelength range of λ1nm-λ2nm is R. n (λ), the spectral response spectrum of the energy detector is S d(λ) can then be used to calculate the theoretical reflectance of the test sample 10 in the small reflectance testing system based on the DPP light source proposed in this application.

[0077]

[0078] Step 6: Obtain the reflectance R of the sample based on the reflectance testing system to be verified. t =E 11r / (E 11i *F);

[0079] Step 7: Compare the theoretical reflectance R of the sample theory and the experimentally measured reflectance R t The difference is used to verify the reflectivity comparison and evaluate the accuracy of the test results of the narrowband small reflectivity testing system based on the DPP light source.

[0080] For ease of understanding, this application provides the following: Figure 3 The diagram shown illustrates the process of comparing and verifying reflectance.

[0081] The inventors of this application have established a small-scale reflectivity testing system based on a DPP light source, according to the reflectivity testing system proposed in this application. Using the aforementioned reflectivity comparison and verification method, a MoSi multilayer film mirror manufactured by OptexFab in Germany was used as the test sample 10 for reflectivity comparison and verification. Finally, the theoretical reflectivity R was obtained. theory The reflectance R measured in experiments was 50.22%. t The reflectance was 49.43%, and the absolute value of reflectance differed by 0.79%, which indicates that the reflectance testing system of this application has a high testing accuracy.

[0082] The advantages of this disclosure compared to the prior art are:

[0083] Compared with the prior art, the reflectivity testing system provided in this application has a simple structure and can verify and improve the accuracy of the test results through the reflectivity comparison verification method provided in this application. Therefore, it can ensure the accuracy of reflectivity testing while miniaturizing the reflectivity testing system.

[0084] To achieve the same structure, those skilled in the art can also devise methods that are not entirely identical to those described above. Furthermore, although various embodiments have been described separately above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination.

[0085] The embodiments of this disclosure have been described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of this disclosure. The scope of this disclosure is defined by the appended claims and their equivalents. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of this disclosure, and all such substitutions and modifications should fall within the scope of this disclosure.

Claims

1. A reflectance comparison verification method for verifying a reflectance testing system, the reflectance testing system comprising: A light source system, a collection mirror chamber, and a sample testing chamber are arranged sequentially along the optical path; the collection mirror chamber is equipped with a focusing collection mirror, and the sample testing chamber is equipped with a filter, an energy normalization structure, a first energy detector, a displacement stage, and a second energy detector. The light source system is used to generate an irradiation source, the light beam emitted by which is a broadband light with a certain divergence angle; the focusing and collecting mirror is used to reflect and focus the light beam emitted by the irradiation source, the focal point being located in the sample testing chamber and between the filter and the energy normalization structure; in the sample testing chamber, the light beam reflected and focused by the focusing and collecting mirror is filtered by the filter and then focused at the focal point, and the light beam continues to propagate into the energy normalization structure after passing through the focal point; the energy normalization structure extracts two beams of light, namely a test beam and a monitoring beam, the monitoring beam entering the first energy detector, and the test beam incident on the surface of the sample to be tested, and after being reflected by the sample surface, entering the second energy detector; The displacement stage is used to mount the sample to be tested and the second energy detector, and can adjust the test position of the sample and the detection position of the second energy detector. The method is characterized by comprising: The standard reflectivity testing apparatus used for comparative verification is determined. This standard reflectivity testing apparatus uses a synchrotron radiation source and the test beam is highly monochromatic s-polarized light. The test beam of the reflectivity testing system to be verified is non-monochromatic unpolarized light. The reflectance spectrum R of the sample under unpolarized light was obtained using the standard reflectance testing device. n (λ), where λ represents the wavelength; Calculate the test beam spectrum S of the reflectivity testing system to be verified. in (λ)=S(λ)×R(λ)×T(λ); where S(λ) represents the radiation spectrum distribution of the irradiation source generated by the light source system, R(λ) represents the reflection spectrum of the focusing and collecting mirror, and T(λ) represents the transmission spectrum of the filter. Calculate the reflected light spectrum S of the sample in the reflectivity testing system to be verified. r (λ)= S in (λ) ×R n (λ); Calculate the theoretical reflectance of the sample Among them, the spectrum of the test beam incident on the sample, S in (λ) wavelength range in nm- Between nm, S d (λ) represents the spectral response spectrum of the energy detector; The reflectance R of the sample was obtained based on the reflectance testing system to be verified. t This includes: activating the light source system; removing the sample to be tested from the optical path before the sample reflectivity test; and using a first energy detector to detect the energy E of the monitoring beam. 9i The energy E of the test beam was detected using a second energy detector. 11i During the sample reflectivity test, the sample to be tested is adjusted to a preset position in the optical path, the incident angle is set to θ, and the second energy detector is adjusted to a position of 2θ. At this time, the energy E of the reflected light from the sample is detected using the second energy detector. 11r The energy E of the monitoring beam is detected using the first energy detector. 9r The energy normalization calibration factor F=E was calculated. 9r / E 9i ; through formula R t =E 11r / (E 11i *F) The reflectance R of the sample is calculated. t ; The theoretical reflectance of the comparison sample and the experimentally measured reflectance R t The difference is used to verify the reflectivity comparison.

2. The reflectance comparison verification method according to claim 1, characterized in that, The reflectance spectrum R of the sample under unpolarized light is obtained using the standard reflectance testing device. n (λ), including: The reflectance of the sample is tested using the standard reflectance testing device, and the reflectance of the sample under unpolarized light is calculated based on the reflectance of the sample under two different degrees of s-polarized light. ;in, This represents the reflectivity under s-polarized light. This represents the reflectivity under p-polarized light; The reflection spectrum of the sample under unpolarized light was obtained by scanning the incident light wavelength.

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