Irradiation in-situ transmittance measuring device and method

Abstract

The invention discloses an irradiation in-situ transmittance measuring device and method, and the device comprises a light source module which is used for emitting a light beam; the light transmission module comprises a first cavity and a light beam modulation assembly, a beam splitting element and a first detector which are arranged in the first cavity, the light beam enters the first cavity and is incident to the light beam modulation assembly, the light beam is shaped or / and the size of the light beam is adjusted, and the beam splitting element splits the light beam into one path of monitoring light beam which is incident to the first detector; the other path of main light beam is split to enter a measuring module, and a first detector detects the first light intensity of the monitoring light beam; the measuring module comprises a control device, a second cavity and a second detector arranged in the second cavity, the sample is located in the second cavity, the main light beam enters the second cavity to irradiate the sample, and the second detector detects the second light intensity of transmission light generated after the main light beam irradiates the sample; the real-time characterization of the irradiation performance change of the sample in the photoetching environment is realized by simulating the photoetching environment and acquiring the transmission light intensity in real time.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to an irradiation in-situ transmittance measurement device and method. Background Art

[0002] In semiconductor chip manufacturing, photomasks are repeatedly exposed to high-power laser light during the photolithography process. Repeated exposure to high-power lasers can cause chemical bond breakage and form defects in the photomask, leading to changes in material properties such as transmittance, optical uniformity, and stress birefringence. This can severely impact the photolithography process and, consequently, chip performance. Therefore, testing the radiation resistance of photomask substrates is crucial. Measuring the transmittance of photomask substrates after irradiation is one of the test items in this radiation resistance test.

[0003] Existing transmittance measurements are all non-in-situ measurements, and cannot obtain real-time changes in transmittance during the photomask irradiation test; nor can they realize the modulation and humidity measurement of the gas atmosphere during optical path transmission and sample irradiation, and cannot simulate the environment of the photomask in actual lithography. Summary of the Invention

[0004] The purpose of the present invention is to provide an in-situ irradiation transmittance measurement device and method, which can simulate the photolithography environment and obtain the transmitted light intensity in real time to achieve real-time characterization of the irradiation performance changes of the photomask sample in the photolithography environment, thereby improving the accuracy of the sample transmittance measurement.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] An irradiation in-situ transmittance measurement device includes a light source module, a light transmission module and a measurement module;

[0007] The light source module is used to emit a light beam;

[0008] The optical transmission module includes a first cavity and a beam modulation component, a beam splitting element, and a first detector disposed in the first cavity. The beam modulation component is used to receive the light beam emitted by the light source module and shape the light beam and / or adjust the size of the light beam. The beam splitting element is disposed on the light output side of the beam modulation component and is used to split the light beam into a monitoring beam that is incident on the first detector and another main beam that is incident on the measurement module. The first detector is used to detect the first light intensity of the monitoring beam.

[0009] The measurement module includes a second cavity and a second detector arranged in the second cavity. The sample is in the second cavity, the main light beam enters the second cavity to irradiate the sample, and the second detector is used to detect a second light intensity of the transmitted light formed after the main light beam irradiates the sample.

[0010] Optionally, the beam modulation component includes a cylindrical concave lens and a cylindrical convex lens, the plane of the cylindrical concave lens is parallel to the plane of the cylindrical convex lens and perpendicular to the direction of the light beam, and the light beam passes through the cylindrical concave lens and the cylindrical convex lens in turn, and the spot shape of the light beam changes but the emission angle remains unchanged.

[0011] Optionally, the beam modulation assembly includes a concave lens and a convex lens, and the first focus of the concave lens and the second focus of the convex lens coincide with each other, so that the emission angle of the light beam does not change after passing through the concave lens and the convex lens in sequence, and the radial size of the light beam changes, the first focus is the focus on the light incident side of the concave lens, and the second focus is the focus on the light incident side of the convex lens.

[0012] Optionally, the optical transmission module further includes:

[0013] An optical attenuator is disposed in the first cavity and located on the light incident side of the light beam modulation component, and is used to regulate the energy of the light beam.

[0014] Optionally, the first cavity is provided with a first air inlet and a first air outlet, the first air inlet is used to introduce protective gas into the first cavity through the first air inlet, the absorption rate of the protective gas to the wavelength of light corresponding to the light beam is less than a preset value, and the first air outlet is used to discharge the gas in the first cavity.

[0015] Optionally, the second cavity is provided with a second air inlet and a second air outlet, the second air inlet is used to introduce working gas into the second cavity through the second air inlet so that the gas environment in the second cavity meets the radiation test requirements, and the second air outlet is used to discharge the gas in the second cavity.

[0016] Optionally, the measurement module further includes:

[0017] A humidity measuring device, wherein the air inlet of the humidity measuring device is connected to the second cavity and is used to measure the humidity in the second cavity.

[0018] Optionally, the measurement module further includes a control device, which is connected to the first detector and the second detector respectively, and is used to calculate the transmittance of the sample according to the first light intensity and the second light intensity.

[0019] Optionally, the measurement module further includes a sample stage disposed in the second cavity, the sample stage is used to place the sample and is connected to the control device, and the control device controls the sample stage to move in three dimensions.

[0020] A method for measuring in-situ irradiation transmittance, applied to any of the above-mentioned in-situ irradiation transmittance measuring devices, comprising:

[0021] When no sample is placed in the second cavity of the measuring module, the light source module emits a light beam to obtain a first light intensity detected by the first detector and a second light intensity detected by the second detector, which are represented as an initial first light intensity and an initial second light intensity, respectively;

[0022] After the sample is placed in the second cavity of the measurement module, the light source module emits a light beam, and the main light beam split by the beam splitting element is irradiated onto the position to be measured of the sample, thereby obtaining a first light intensity detected by the first detector and a second light intensity detected by the second detector, which are represented as a current first light intensity and a current second light intensity, respectively;

[0023] The transmittance of the position to be measured of the sample is obtained according to the initial first light intensity, the initial second light intensity, the current first light intensity, and the current second light intensity.

[0024] Optionally, the measurement module further comprises a sample stage disposed in the second cavity, the sample stage being used to place the sample and being connected to the control device, and the control device controlling the sample stage to move in three dimensions;

[0025] After the sample is placed in the second cavity of the measurement module, the light source module emits a light beam, and the main light beam split by the beam splitting element is irradiated to the position to be measured of the sample, and obtaining the first light intensity detected by the first detector and the second light intensity detected by the second detector includes:

[0026] After the sample is placed on the sample stage of the measurement module, the sample stage is controlled to move sequentially to drive the sample to move, so that the main light beam split by the beam splitting element is irradiated to different positions to be measured on the sample. After each movement of the sample, the main light beam split by the beam splitting element is irradiated to the position to be measured on the sample, a first light intensity detected by the first detector and a second light intensity detected by the second detector are obtained, which are respectively represented as the current first light intensity and the current second light intensity, and position data of the position to be measured of the sample is obtained according to the position of the sample stage;

[0027] Obtaining the transmittance of the position to be measured of the sample according to the initial first light intensity, the initial second light intensity, the current first light intensity, and the current second light intensity includes:

[0028] For any position to be measured of the sample, the transmittance of the current position to be measured of the sample is obtained according to the initial first light intensity, the initial second light intensity, and the current first light intensity and the current second light intensity corresponding to the current position to be measured.

[0029] As can be seen from the above technical solution, the present invention provides an irradiation in-situ transmittance measurement device and method, which includes a light source module, an optical transmission module and a measurement module; the light source module is used to emit a light beam; the optical transmission module includes a first cavity and a beam modulation component, a beam splitting element and a first detector arranged in the first cavity, the beam modulation component is used to receive the light beam emitted by the light source module, and shape the light beam or / and adjust the size of the light beam; the beam splitting element is arranged on the light output side of the beam modulation component, and is used to split the light beam into a monitoring beam that is incident on the first detector, and split another main beam that is incident on the measurement module, the first detector is used to detect the first light intensity of the monitoring beam; the measurement module includes a control device, a second cavity and a second detector arranged in the second cavity, the sample is in the second cavity, the main beam enters the second cavity to irradiate the sample, the second detector is used to detect the second light intensity of the transmitted light formed after the main beam is irradiated to the sample, and the control device is connected to the first detector and the second detector respectively, and is used to calculate the transmittance of the sample based on the first light intensity and the second light intensity.

[0030] The irradiation in-situ transmittance measurement device and method of the present invention can achieve in-situ measurement of the transmittance of the sample / photomask during the irradiation test process without moving the sample during the irradiation process of the light beam. By measuring the light intensity of the monitoring beam and the light intensity of the transmitted light formed after the main beam irradiates the sample, the performance changes of the sample during the irradiation test can be evaluated in real time, thereby improving the accuracy of the sample transmittance measurement.

[0031] In addition, based on the gas atmosphere adjustment of the laser transmission closed chamber and the sample irradiation closed chamber, and the simulation of the lithography environment through the humidity detection system, real-time characterization of the changes in the irradiation performance of the sample / photomask in the lithography environment can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0033] Figure 1 A schematic diagram of an irradiation in-situ transmittance measurement device provided in an embodiment of the present application;

[0034] Figure 2Schematic diagram of a beam modulation assembly of an irradiation in-situ transmittance measurement device according to an embodiment of the present application, including a cylindrical concave lens and a cylindrical convex lens;

[0035] Figure 3 This is a schematic diagram of a size adjustment component of an irradiation in-situ transmittance measurement device according to an embodiment of the present application, including a concave lens and a convex lens;

[0036] Figure 4 A schematic diagram of a measurement module of an irradiation in-situ transmittance measurement device according to an embodiment of the present application;

[0037] Figure 5 This is a flow chart of a method for measuring in-situ transmittance under irradiation provided in an embodiment of the present application.

[0038] The reference numerals in the drawings of the specification include:

[0039] 1-light source module, 10-light source, 11-third cavity, 12-fourth light port;

[0040] 2- optical transmission module, 20- first cavity, 21- beam modulation assembly, 22- beam splitting element, 23- first detector, 24- beam shaping assembly, 240- cylindrical concave lens, 241- cylindrical convex lens, 25- size adjustment assembly, 250- concave lens, 251- convex lens, 26- optical attenuator, 27- first reflecting element, 28- second reflecting element, 29- aperture, 201- first light opening, 202- second light opening;

[0041] 3- measurement module, 30- second cavity, 31- second detector, 32- control device, 33- sample stage, 34- third light port, 35- second air inlet, 36- second air outlet, 37- humidity measurement device, 4- sample. DETAILED DESCRIPTION

[0042] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0043] This embodiment provides an irradiation in-situ transmittance measurement device, comprising a light source module, a light transmission module, and a measurement module;

[0044] The light source module is used to emit a light beam;

[0045] The optical transmission module includes a first cavity and a beam modulation component, a beam splitting element, and a first detector disposed in the first cavity. The beam modulation component is used to receive the light beam emitted by the light source module and shape the light beam and / or adjust the size of the light beam. The beam splitting element is disposed on the light output side of the beam modulation component and is used to split the light beam into a monitoring beam that is incident on the first detector and another main beam that is incident on the measurement module. The first detector is used to detect the first light intensity of the monitoring beam.

[0046] The measurement module includes a second cavity and a second detector arranged in the second cavity. The sample is in the second cavity, the main light beam enters the second cavity to irradiate the sample, and the second detector is used to detect a second light intensity of the transmitted light formed after the main light beam irradiates the sample.

[0047] The irradiation in-situ transmittance measurement device of this embodiment can measure the transmittance of the sample by measuring the light intensity of the monitoring beam and the light intensity of the transmitted light formed after the main beam is irradiated to the sample during the process of irradiating the sample with the light beam. There is no need to move the sample between the process of irradiating the sample and the process of measuring the transmittance of the sample. The in-situ measurement of the transmittance of the sample / photomask during the irradiation test can be realized, and the performance changes of the sample during the irradiation test can be evaluated in real time.

[0048] For example, you can refer to Figure 1 , Figure 1 A schematic diagram of an irradiation in-situ transmittance measurement device provided in an embodiment of the present application. As shown in the figure, the outgoing light beam of the light source module 1 is incident on the first cavity 20 and is incident on the beam modulation component 21. The light beam passing through the beam modulation component 21 is incident on the beam splitting element 22. The beam splitting element 22 splits the light beam into a monitoring beam and another main beam. The monitoring beam is incident on the first detector 23. The first detector 23 detects the first light intensity of the monitoring beam. The main beam is incident on the second cavity 30 and irradiates the sample 4. The second detector 31 detects the second light intensity of the transmitted light of the sample 4.

[0049] The output light beam of the light source module 1 may be a laser, which can irradiate the sample 4 .

[0050] In some embodiments, the wavelength of the output light beam may be in the range of 190-370 nm, and may be a quasi-continuous laser with a pulse frequency of up to 6000 Hz, and the pulse frequency may be selected according to test requirements.

[0051] In some embodiments, the light source module 1 includes a light source 10 and a third cavity 11, and the light source 10 is disposed in the third cavity 11. A protective gas whose absorption rate for light of a wavelength corresponding to the light beam is less than a preset value can be filled in the third cavity 11. The absorption rate of the protective gas for light of a wavelength corresponding to the light beam is small. In this way, compared with the third cavity 11 being filled with ordinary atmosphere, the absorption of light of a wavelength corresponding to the light beam by ordinary atmosphere can be avoided, the photolithography environment can be more accurately simulated, and the accuracy of irradiating the sample 4 and measuring the transmittance can be improved. For example, the wavelength range of the output light beam of the light source 10 is 190-370 nm, and the absorption rate of the protective gas for light of a wavelength range of 190-370 nm is small. The protective gas includes but is not limited to nitrogen N2 or argon Ar. The third cavity 11 can be provided with a fourth light port 12, and the output light beam of the light source 10 is emitted from the fourth light port 12. The light source 10 can be a laser. In some embodiments, the beam modulation component 21 includes a beam shaping component 24 for shaping the light beam. In practical applications, the emitted light beam from light source module 1 has different dimensions in the X and Y directions, which are perpendicular to the Z beam direction. However, when irradiating sample 4, the corresponding spot of the light beam irradiating sample 4 is required to have uniform dimensions in the X and Y directions. The beam modulator 21 achieves beam shaping by varying the dimensions of the corresponding spot in the X and Y directions. In this embodiment, the structure of the beam shaping assembly 24 is not limited, as long as it can shape the beam as required.

[0052] In some embodiments, the beam modulation assembly 21 includes a cylindrical concave lens 240 and a cylindrical convex lens 241. Each of the cylindrical concave lens 240 and the cylindrical convex lens 241 consists of a cylindrical surface and a flat surface. The flat surface of the cylindrical concave lens 240 is parallel to the flat surface of the cylindrical convex lens 241 and perpendicular to the direction of the light beam. As the light beam passes through the cylindrical concave lens 240 and the cylindrical convex lens 241 in sequence, the spot shape of the light beam changes, while the emission angle remains unchanged. The cylindrical surface of the cylindrical concave lens 240 is concave, while the cylindrical surface of the cylindrical convex lens 241 is convex. Specifically, if the direction of the light beam is the Z direction, the X direction and the Y direction are perpendicular to the light beam direction, the plane of the cylindrical concave lens 240 and the plane of the cylindrical convex lens 241 are both parallel to the X direction / Y direction, and the generatrix of the concave surface of the cylindrical concave lens 240 and the generatrix of the convex surface of the cylindrical convex lens 241 are both parallel to the Y direction, so that when the light beam passes through the concave surface of the cylindrical concave lens 240 and the convex surface of the cylindrical convex lens 241, the size of the corresponding light spot of the light beam in the Y direction does not change, and only the size of the light spot in the X direction changes (the size is expanded or reduced). If the beam direction is in the Z direction, and the X and Y directions are perpendicular to the beam direction, the planes of cylindrical concave lens 240 and cylindrical convex lens 241 are both parallel to the X / Y directions, and the generatrices of the concave surface of cylindrical concave lens 240 and the generatrices of the convex surface of cylindrical convex lens 241 are both parallel to the X direction. This means that when the beam passes through the concave surface of cylindrical concave lens 240 and the convex surface of cylindrical convex lens 241, the size of the corresponding light spot in the X direction remains unchanged, and only the size of the light spot in the Y direction is changed (increased or reduced). In this way, the cylindrical concave lens 240 and cylindrical convex lens 241 achieve beam shaping.

[0053] The emission angle of the light beam does not change after passing through the cylindrical concave lens 240 and the cylindrical convex lens 241 in sequence. Therefore, after the parallel light passes through the cylindrical concave lens 240 and the cylindrical convex lens 241 in sequence, the emitted light is still parallel light. The focus of the cylindrical concave lens 240 on the side where the light enters the cylindrical concave lens 240 coincides with the focus of the cylindrical convex lens 241 on the side where the light enters the cylindrical convex lens 241. In this way, the emission angle of the light beam does not change after passing through the cylindrical concave lens 240 and the cylindrical convex lens 241 in sequence. For example, the focal length of the cylindrical concave lens 240 is f1, and the focal length of the cylindrical convex lens 241 is f2. After the light beam passes through the cylindrical concave lens 240 and the cylindrical convex lens 241 in sequence, the size of the corresponding light spot of the light beam in the X direction / Y direction is expanded by |f1 / f2| times or reduced by |f1 / f2| times.

[0054] For example, you can refer to Figure 2 , Figure 2 This is a schematic diagram of a beam modulation component of an irradiation in-situ transmittance measurement device according to an embodiment of the present application, which includes a cylindrical concave lens and a cylindrical convex lens. Figure 2As shown, cylindrical concave lens 240 is a plano-concave cylindrical lens, and cylindrical convex lens 241 is a plano-convex cylindrical lens. The planes of cylindrical concave lens 240 and cylindrical convex lens 241 are both parallel to the X / Y direction plane, and the generatrices of the concave surface of cylindrical concave lens 240 and the generatrices of the convex surface of cylindrical convex lens 241 are both parallel to the Y direction. The focal point of cylindrical concave lens 240 on the light incident side coincides with the focal point of cylindrical convex lens 241 on the light incident side, i.e., they are confocal. This ensures that the divergence angle of the light beam does not change after passing through cylindrical concave lens 240 and cylindrical convex lens 241 in sequence. Since the corresponding light spot of the incident light beam has different dimensions in the X and Y directions, with the dimension in the Y direction being larger than the dimension in the X direction, the corresponding light spot of the light beam remains unchanged in the Y direction after passing through cylindrical concave lens 240 and cylindrical convex lens 241 in sequence, but expands in the X direction by a factor of |f1 / f2|. The focal length of cylindrical concave lens 240 is f1, and the focal length of cylindrical convex lens 241 is f2. In some embodiments, beam modulation assembly 21 further includes a size adjustment assembly 25 for adjusting the size of the beam. In this embodiment, the structure of size adjustment assembly 25 is not limited, as long as it can adjust the beam size as required.

[0055] In some embodiments, the size adjustment component 25 includes a concave lens and a convex lens, and the first focus of the concave lens and the second focus of the convex lens coincide with each other, so that the emission angle of the light beam does not change after passing through the concave lens and the convex lens in sequence, and the radial size of the light beam changes, the first focus is the focus located on the light incident side of the concave lens, and the second focus is the focus located on the light incident side of the convex lens. The emission angle of the light beam does not change after passing through the concave lens and the convex lens in sequence, so after the parallel light passes through the concave lens and the convex lens in sequence, the emitted light is still parallel light. The radial size of the light beam changes after passing through the concave lens and the convex lens in sequence, and the radial size of the light beam may be expanded or reduced. Exemplarily, the focal length of the concave lens is f3, and the focal length of the convex lens is f4. After the light beam passes through the concave lens and the convex lens in sequence, the corresponding light spot of the light beam can be expanded by |f4 / f3| times or reduced by |f4 / f3| times in a single direction, and the area of the light spot can be expanded or reduced by |f4 / f3| 2 In practical applications, concave lenses and convex lenses with corresponding focal lengths can be selected as required so that the size of the light beam after passing through the size adjustment component 25 meets the requirements.

[0056] For example, you can refer to Figure 3 , Figure 3This is a schematic diagram of a sizing assembly for an irradiation in-situ transmittance measurement device according to an embodiment of the present invention, including a concave lens and a convex lens. As shown, the first focal point of concave lens 250 and the second focal point of convex lens 251 coincide, both located at point F. The focal length of concave lens 250 is f3, and the focal length of convex lens 251 is f4. After the light beam passes through concave lens 250 and convex lens 251, the corresponding spot of the light beam is radially expanded by a factor of |f4 / f3|, and the spot area is expanded by |f4 / f3|. 2 times.

[0057] In some embodiments, the optical transmission module 2 further includes an optical attenuator 26 disposed within the first cavity 20 and on the light-entering side of the beam modulation assembly 21, for regulating the energy of the light beam. The light beam entering the first cavity 20 is incident on the optical attenuator 26. The energy of the light beam is regulated as it passes through the optical attenuator 26, ensuring that the energy of the light beam ultimately irradiated on the sample 4 meets the required level.

[0058] In some embodiments, the optical transmission module 2 further includes: at least one reflective element disposed within the first cavity 20 and located on the light incident side of the beam modulation assembly 21, configured to deflect the transmission optical path of the light beam via the at least one reflective element, so that the light beam is reflected by the at least one reflective element and transmitted to the beam modulation assembly 21. In this embodiment, the number and arrangement of the at least one reflective element are not limited. In practical applications, it is sufficient that the light beam incident into the first cavity 20 is transmitted to the beam modulation assembly 21 after passing through the at least one reflective element. The reflective element can be, but is not limited to, a mirror.

[0059] For example, you can refer to Figure 1 As shown, a first reflecting element 27, a second reflecting element 28 and an optical attenuator 26 are sequentially arranged in the first cavity 20. The first reflecting element 27 and the second reflecting element 28 are arranged opposite to and in parallel. The light beam incident into the first cavity 20 is sequentially reflected by the first reflecting element 27 and the second reflecting element 28 and then transmitted to the optical attenuator 26. After passing through the optical attenuator 26, it is incident on the beam modulation component 21.

[0060] In some embodiments, the optical transmission module 2 further includes an aperture 29 disposed in the first cavity 20 and located on the light incident side of the beam splitting element 22 , for allowing the light beam to pass through the aperture 29 and then be incident on the beam splitting element 22 .

[0061] In some embodiments, the first cavity 20 is provided with a first light opening 201 and a second light opening 202. The first light opening 201 is used to allow the light beam to pass through and enter the first cavity 20, and the second light opening 202 is used to allow the main light beam to pass through and exit. The second cavity 30 is provided with a third light opening 34. The third light opening 34 allows the main light beam emitted from the second light opening 202 to pass through and enter the second cavity 30.

[0062] For example, you can refer to Figure 1 As shown, the outgoing light beam of the light source 10 is emitted from the fourth light port 12, and the outgoing light beam is incident on the first light port 201 of the first cavity 20. The light beam enters the first cavity 20 through the first light port 201, and the main light beam split by the beam splitting element 22 is incident on the third light port 34 of the second cavity 30 through the second light port 202.

[0063] In some embodiments, the first light opening 201 of the first cavity 20 may be provided with a window, the second light opening 202 may be provided with a window, the third light opening 34 of the second cavity 30 may be provided with a window, and the fourth light opening 12 of the third cavity 11 may be provided with a window. The windows may be made of optical materials with a transmittance of ≥80% for light of the working wavelength (i.e., light of the wavelength corresponding to the output light beam of the light source module 1), including but not limited to quartz glass, CaF2 glass, or BK7 glass.

[0064] In some embodiments, the first cavity 20 is provided with a first air inlet and a first air outlet. The first air inlet is used to introduce a protective gas into the first cavity 20 through the first air inlet. The protective gas has an absorption rate of light of the wavelength corresponding to the light beam that is less than a preset value. The first air outlet is used to discharge the gas within the first cavity 20. The absorption rate of the protective gas for light of the wavelength corresponding to the light beam that is less than a preset value reduces the absorption rate of the protective gas for light of the wavelength corresponding to the light beam. This can prevent the absorption of light of the wavelength corresponding to the light beam by ordinary atmosphere compared to a cavity 20 filled with ordinary atmosphere, thereby improving the accuracy of irradiating the sample 4 and measuring the transmittance. The protective gas includes, but is not limited to, nitrogen N2 or argon Ar. The first cavity 20 is a sealed cavity.

[0065] In some embodiments, the measurement module 3 may further include a control device 32 , and the control device 32 is connected to the first detector 23 and the second detector 31 , respectively.

[0066] In some embodiments, the measurement module 3 may further include a sample stage 33 disposed within the second cavity 30. The sample stage 33 is used to place the sample 4 and is movable in three dimensions. The three-dimensional movement of the sample stage 33 can also drive the sample 4 to move in three dimensions. In some embodiments, the minimum step size of the sample stage 33 is better than 20 μm, and the repeatability is better than 30 μm.

[0067] In some embodiments, the sample stage 33 can carry the sample 4 based on a side clamping method, and the control device 32 can be connected to the sample stage 33 to control the movement of the sample stage 33 in three dimensions.

[0068] In some embodiments, the second cavity 30 is provided with a second gas inlet 35 and a second gas outlet 36. The second gas inlet 35 is used to introduce a working gas into the second cavity 30, ensuring that the gas environment within the second cavity 30 meets the requirements of the irradiation test. The second gas outlet 36 is used to exhaust the gas within the second cavity 30. Depending on the gas conditions required for irradiating the sample 4, the working gas can be added to the second cavity 30 to meet the requirements of the irradiation test under different gas conditions. The working gas includes, but is not limited to, nitrogen N2, argon Ar, or high-purity compressed air XCDA. The second cavity 30 is a sealed cavity.

[0069] For example, you can refer to Figure 4 , Figure 4 This is a schematic diagram of a measurement module of an irradiation in-situ transmittance measurement device according to an embodiment. As shown in the figure, the second cavity 30 is a sealed cavity, the sample 4 is located in the second cavity 30, and the second cavity 30 is provided with a second air inlet 35 and a second air outlet 36. The working gas is introduced into the second cavity 30 through the second air inlet 35, and the gas in the second cavity 30 can be discharged through the second air outlet 36.

[0070] In some embodiments, the measurement module 3 may further include: a humidity measuring device 37, whose air inlet is connected to the second cavity 30, for measuring the humidity within the second cavity 30. By measuring the humidity within the second cavity 30 by the humidity measuring device 37, it is possible to monitor whether the humidity environment meets the irradiation test requirements. The humidity measuring device 37 can be, but is not limited to, a moisture meter. In this embodiment, the sample 4 is located in the second cavity 30, and a working gas is filled into the second cavity 30 to meet the gas conditions required for irradiation of the sample 4. The humidity is monitored by the humidity measuring device 37. If the sample 4 is a photomask substrate, a photolithography environment can be simulated to perform irradiation testing, which assists in product development and verification.

[0071] In some embodiments, the first light opening 201 of the first cavity 20 of the optical transmission module 2 can be aligned with the fourth light opening 12 of the third cavity 11 of the light source module 1. In this way, the light beam emitted from the fourth light opening 12 of the light source module 1 can directly enter the first light opening 201 of the optical transmission module 2, thereby reducing beam energy loss. The second light opening 202 of the first cavity 20 of the optical transmission module 2 can be aligned with the third light opening 34 of the second cavity 30 of the measurement module 3. In this way, the light beam emitted from the second light opening 202 of the optical transmission module 2 can directly enter the third light opening 34 of the measurement module 3, thereby reducing beam energy loss.

[0072] The first detector 23 may be, but not limited to, an energy meter or a light energy detector, and the second detector 31 may be, but not limited to, an energy meter or a light energy detector. The control device 32 may be a control terminal device.

[0073] This embodiment also provides an irradiation in-situ transmittance measurement method, which is applied to the irradiation in-situ transmittance measurement device described in any of the above embodiments. Figure 5 , Figure 5 A flow chart of an in-situ irradiation transmittance measurement method provided in one embodiment includes the following steps:

[0074] S11: When no sample 4 is placed in the second cavity 30 of the measuring module 3, the light source module 1 emits a light beam to obtain a first light intensity detected by the first detector 23 and a second light intensity detected by the second detector 31, which are represented as initial first light intensity and initial second light intensity, respectively;

[0075] S12: After placing the sample 4 in the second cavity 30 of the measurement module 3, the light source module 1 emits a light beam, and the main light beam split by the beam splitting element 22 is incident on the position to be measured of the sample 4, and a first light intensity detected by the first detector 23 and a second light intensity detected by the second detector 31 are obtained, which are represented as the current first light intensity and the current second light intensity, respectively;

[0076] S13: Obtaining the transmittance of the position to be measured of the sample 4 according to the initial first light intensity, the initial second light intensity, the current first light intensity, and the current second light intensity.

[0077] The irradiation in-situ transmittance measurement method of this embodiment can achieve in-situ measurement of the transmittance of the sample / photomask during the irradiation test process without moving the sample during the process of irradiating the sample with a light beam, by measuring the light intensity of the monitoring beam and the light intensity of the transmitted light formed after the main beam is irradiated to the sample. It can evaluate the performance changes of the sample during the irradiation test in real time and improve the accuracy of the sample transmittance measurement.

[0078] In addition, based on the gas atmosphere adjustment of the laser transmission closed chamber and the sample irradiation closed chamber, and the simulation of the lithography environment through the humidity detection system, real-time characterization of the changes in the irradiation performance of the sample / photomask in the lithography environment can be achieved.

[0079] In some embodiments, the initial first light intensity is E_1, the initial second light intensity is E_2, the current first light intensity is E_1´, and the current second light intensity is E_2´. Therefore, before testing (i.e., before sample 4 is placed on measurement module 3), the splitting ratio is α = E_2 / E_1, the splitting ratio during irradiation of sample 4 is β = E_2´ / E_1´, and the transmittance of sample 4 is β / α. In this way, the real-time transmittance of sample 4 during irradiation can be obtained.

[0080] In some embodiments, the measurement module 3 further includes a sample stage 33 disposed within the second cavity 30, the sample stage 33 being configured to place the sample 4 and movable in three dimensions. After the sample 4 is placed within the second cavity 30 of the measurement module 3, the light source module 1 is caused to emit a light beam, and the main light beam split by the beam splitter 22 is irradiated onto a position to be measured on the sample 4. Obtaining a first light intensity detected by the first detector 23 and a second light intensity detected by the second detector 31 includes: after the sample 4 is placed on the sample stage 33 of the measurement module 3, controlling the sample stage 33 to sequentially move to drive the sample 4 so that the main light beam split by the beam splitter 22 is irradiated onto different positions to be measured on the sample 4. After each movement of the sample 4, the main light beam split by the beam splitter 22 is irradiated onto the position to be measured on the sample 4. Obtaining the first light intensity detected by the first detector 23 and the second light intensity detected by the second detector 31, which are represented as the current first light intensity and the current second light intensity, respectively, and obtaining position data of the position to be measured on the sample 4 based on the position of the sample stage 33.

[0081] Correspondingly, obtaining the transmittance of the measured position of the sample 4 based on the initial first light intensity, the initial second light intensity, the current first light intensity and the current second light intensity includes: for any measured position of the sample 4, obtaining the transmittance of the measured position of the sample 4 based on the initial first light intensity, the initial second light intensity and the current first light intensity and the current second light intensity corresponding to the measured position.

[0082] After the sample 4 is placed on the sample stage 33 of the measurement module 3, the sample stage 33 can be controlled to move sequentially. The movement of the sample stage 33 can drive the movement of the sample 4, so that the main beam split by the beam splitter 22 can be irradiated to different positions to be measured on the sample 4. After each movement of the sample stage 33, the main beam split by the beam splitter 22 can be irradiated to a position to be measured on the sample 4.

[0083] When the main beam is irradiated to any position to be measured on the sample 4, the main beam irradiates the sample 4. At the same time, the first detector 23 detects the current first light intensity of the monitoring beam split by the beam splitting element 22, and the second detector 31 detects the current second light intensity of the transmitted light formed after the main beam is irradiated to the sample 4. Based on the initial first light intensity, the initial second light intensity, and the current first light intensity and the current second light intensity corresponding to the current position to be measured, the transmittance of the current position to be measured of the sample 4 can be obtained. The position data of the current position to be measured of the sample 4 can be obtained based on the position of the sample stage 33. In this way, when the light beam sequentially irradiates different positions to be measured on the sample 4, the transmittance of the sample 4 is measured by measuring the light intensity of the monitoring beam and the light intensity of the transmitted light formed after the main beam is irradiated to the sample 4, so that the real-time transmittance of the position to be measured when the different positions to be measured on the sample 4 are irradiated.

[0084] The following example describes the specific process of measuring the transmittance of sample 4, including the following steps:

[0085] S1: In the irradiation in-situ transmittance measurement device, the light source 10, the beam modulation component 21, and the beam splitting element 22 are sequentially placed on the optical axis. In addition, the corresponding light energy detectors and the control device 32 are placed at designated positions according to the optical path design, and the control device 32 is communicatively connected to the first detector 23 and the second detector 31;

[0086] S2: Start the light source 10 to generate a laser beam with continuously adjustable wavelength. The beam is shaped and modulated in size by the beam modulator 21. The beam is then split into two laser beams with a fixed energy ratio by the beam splitter 22. The beam on the first optical path is the monitoring beam, and the beam on the second optical path is the test beam, i.e., the main beam.

[0087] S3: The monitoring beam of the first optical path is incident on the first detector 23 to obtain the energy E_1 of the monitoring beam; the test beam of the second optical path is incident on the second detector 31 to obtain the energy E_2 of the test beam;

[0088] S4: placing the sample 4 on the sample stage 33 on the optical axis behind the beam splitter 22, and establishing communication between the control device 32 and the controller on the sample stage 33;

[0089] S5: Turn on the control device 32, control the movement of the sample stage 33, move the sample 4 to a designated position, and allow the test light beam to illuminate a certain position to be tested on the sample 4;

[0090] S6: Start the light source 10 to generate a laser beam with continuously adjustable wavelength. The beam is shaped and the beam size is modulated by the beam modulator 21. The beam is then split into two laser beams with a fixed energy ratio by the beam splitter 22. The beam on the first optical path is the monitoring beam, and the beam on the second optical path is the test beam, i.e., the main beam.

[0091] S7: The monitoring beam of the first optical path is incident on the first detector 23 to obtain the energy level E_1′ of the monitoring beam. Meanwhile, the testing beam of the second optical path is incident on the surface of the sample 4 and then incident on the second detector 31 to obtain the energy level E_2′.

[0092] S8: The control device 32 automatically obtains the position coordinates from the controller of the sample stage 33 and the test data from the first detector 23 and the second detector 31 , and then calculates the corresponding transmittance of different positions of the sample 4 .

[0093] The irradiation in-situ transmittance measurement device and method of this embodiment can achieve in-situ transmittance measurement during sample irradiation testing, allowing real-time evaluation of sample performance changes during the irradiation test. By adjusting the gas atmosphere in the sealed chambers of the optical transmission module and the measurement module, and simulating a photolithography environment through humidity detection, changes in the irradiation performance of the sample under the lithography environment can be characterized. For example, the sample is a photomask substrate.

[0094] The above is a detailed introduction to the irradiation in-situ transmittance measurement device and method provided by the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only intended to help understand the method and core concept of the present invention. It should be noted that for those skilled in the art, without departing from the principles of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. An irradiation in-situ transmittance measurement device, characterized in that: It includes a light source module, a light transmission module and a measurement module; The light source module is used to emit a light beam to the light transmission module; The optical transmission module includes a first cavity and a beam modulation component, a beam splitting element, and a first detector disposed in the first cavity. The beam modulation component is used to receive the light beam emitted by the light source module and shape the light beam and / or adjust the size of the light beam. The beam splitting element is disposed on the light output side of the beam modulation component and is used to split the light beam into a monitoring beam that is incident on the first detector and another main beam that is incident on the measurement module. The first detector is used to detect the first light intensity of the monitoring beam. The measurement module includes a second cavity and a second detector arranged in the second cavity. The sample is in the second cavity, the main light beam enters the second cavity to irradiate the sample, and the second detector is used to detect a second light intensity of the transmitted light formed after the main light beam irradiates the sample.

2. The irradiation in-situ transmittance measurement device according to claim 1, characterized in that: The beam modulation component includes a cylindrical concave lens and a cylindrical convex lens. The plane of the cylindrical concave lens is parallel to the plane of the cylindrical convex lens and is perpendicular to the direction of the light beam. The light beam passes through the cylindrical concave lens and the cylindrical convex lens in sequence, and the spot shape of the light beam changes, while the emission angle remains unchanged.

3. The irradiation in-situ transmittance measurement device according to claim 1, characterized in that: The beam modulation assembly includes a concave lens and a convex lens, and the first focus of the concave lens and the second focus of the convex lens coincide with each other, so that the emission angle of the light beam does not change after passing through the concave lens and the convex lens in sequence, and the radial size of the light beam changes. The first focus is the focus on the light incident side of the concave lens, and the second focus is the focus on the light incident side of the convex lens.

4. The irradiation in-situ transmittance measurement device according to claim 1, characterized in that: The optical transmission module further includes: An optical attenuator is disposed in the first cavity and located on the light incident side of the light beam modulation component, and is used to regulate the energy of the light beam.

5. The irradiation in-situ transmittance measurement device according to claim 1, characterized in that: The first cavity is provided with a first air inlet and a first air outlet, the first air inlet is used to pass protective gas into the first cavity through the first air inlet, the absorption rate of the protective gas to the wavelength of light corresponding to the light beam is less than a preset value, and the first air outlet is used to discharge the gas in the first cavity; the second cavity is provided with a second air inlet and a second air outlet, the second air inlet is used to pass working gas into the second cavity through the second air inlet, so that the gas environment in the second cavity meets the irradiation test requirements, and the second air outlet is used to discharge the gas in the second cavity.

6. The irradiation in-situ transmittance measurement device according to claim 1, characterized in that: The measurement module further includes a control device, which is connected to the first detector and the second detector respectively, and is used to calculate the transmittance of the sample according to the first light intensity and the second light intensity.

7. The irradiation in-situ transmittance measurement device according to claim 1, characterized in that: The measurement module further includes: A humidity measuring device, wherein the air inlet of the humidity measuring device is connected to the second cavity and is used to measure the humidity in the second cavity.

8. The irradiation in-situ transmittance measurement device according to claim 6, characterized in that: The measurement module further includes a sample stage disposed in the second cavity. The sample stage is used to place the sample and is connected to the control device. The control device controls the sample stage to move in three dimensions.

9. A method for measuring in-situ irradiation transmittance, applied to the in-situ irradiation transmittance measuring device according to any one of claims 1 to 8, characterized in that: include: When no sample is placed in the second cavity of the measuring module, the light source module emits a light beam to obtain a first light intensity detected by the first detector and a second light intensity detected by the second detector, which are represented as an initial first light intensity and an initial second light intensity, respectively; After the sample is placed in the second cavity of the measurement module, the light source module emits a light beam, and the main light beam split by the beam splitting element is irradiated onto the position to be measured of the sample, thereby obtaining a first light intensity detected by the first detector and a second light intensity detected by the second detector, which are represented as a current first light intensity and a current second light intensity, respectively; The transmittance of the position to be measured of the sample is obtained according to the initial first light intensity, the initial second light intensity, the current first light intensity, and the current second light intensity.

10. The method for measuring in-situ irradiation transmittance according to claim 9, wherein: The measurement module further includes a sample stage disposed in the second cavity, the sample stage being used to place the sample and being connected to the control device, and the control device controlling the sample stage to move in three dimensions; After the sample is placed in the second cavity of the measurement module, the light source module emits a light beam, and the main light beam split by the beam splitting element is irradiated to the position to be measured of the sample, and obtaining the first light intensity detected by the first detector and the second light intensity detected by the second detector includes: After the sample is placed on the sample stage of the measurement module, the control device controls the sample stage to move sequentially to drive the sample to move, so that the main light beam split by the beam splitting element is irradiated to different positions to be measured on the sample. After each movement of the sample, the main light beam split by the beam splitting element is irradiated to the position to be measured on the sample, and a first light intensity detected by the first detector and a second light intensity detected by the second detector are obtained, which are respectively represented as the current first light intensity and the current second light intensity, and position data of the position to be measured of the sample is obtained according to the position of the sample stage; Obtaining the transmittance of the position to be measured of the sample according to the initial first light intensity, the initial second light intensity, the current first light intensity, and the current second light intensity includes: For any position to be measured of the sample, the transmittance of the current position to be measured of the sample is obtained according to the initial first light intensity, the initial second light intensity, and the current first light intensity and the current second light intensity corresponding to the current position to be measured.

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