Apparatus and method for non-destructive in situ measurement of high complexity structures based on Raman spectroscopy

Abstract

This abstract relates to an apparatus and method for non-destructive in-situ measurement of high-complexity structures based on Raman spectroscopy. In this apparatus, a laser source emits a laser beam, a condenser focuses the laser beam above a movable stage, and the focal plane of the condenser is set to an initial position. In the measurement process, the focal plane is moved from the initial position to the surface, side, or bottom surface of the sample to be measured. The movable stage supports the sample to be measured and can move in a plane parallel or perpendicular to the optical path axis. The axial direction of the structure of the sample to be measured is parallel to the optical path axis and is in the focal area of ​​the laser beam. The detection module collects the specific Raman scattering signals returning from the sample, and determines the planar and three-dimensional structures of the sample to be measured based on the measurement results. This apparatus performs rapid, non-destructive, and precise measurements of the structure, composition, defects, stress, etc. of samples with complex surfaces. This allows efficient and low-cost in-situ evaluation of processing quality and microstructural characteristics, providing data for structure analysis and quality verification.

Description

[Technical field]

[0001] The present invention relates to the field of measurement technology, and in particular to a device and method for the non-destructive in-situ high complexity structure measurement based on Raman spectroscopy. [Background technology]

[0002] With the development of integrated circuits, microelectromechanical systems (MEMS), and 3D printing manufacturing technologies, highly complex microstructures are widely used, and the requirements for measurement techniques for highly complex microstructures are also increasing. In particular, with the development of advanced three-dimensional packaging technology and 3D NAND flash memory, more complex three-dimensional chip structures have emerged, which poses high challenges to the exploration of the shape, composition, and defects of three-dimensional structures during the processing process.

[0003] As a means of measuring microstructures in related technologies, surface measurement techniques such as step meters and atomic force microscopes (AFM) have limitations in the measurement range of highly complex structures. Scanning electron microscopes (SEM) have high measurement accuracy and are one of the common characterization methods for the shape and composition of complex structures in the semiconductor industry, but they require sequential cutting of the sample from the side, which is destructive and does not allow in situ and non-destructive analysis.

[0004] US Patent US 2016O161730A1 discloses a measurement technique based on the interference of light, which uses interference to measure the optical path difference in air between the surface and bottom reflected light of a micro-hole to obtain the depth of the hole. However, the white light or near-infrared light beam used in this type of technique is easily blocked or adjusted by the wall surface of the high-complexity structure, has low resolution, and cannot provide properties such as material composition and stress. In order to improve structure analysis and quality monitoring, there is still a need to develop a rapid, convenient and non-destructive in-situ measurement method for high-complexity structures and properties. Summary of the Invention [Means for solving the problem]

[0005] In light of this, the present invention proposes an apparatus and method for non-destructive in situ high-complexity structure measurement based on Raman spectroscopy.

[0006] The present invention provides a non-destructive in-situ high complexity structure measurement device based on Raman spectroscopy, which is used to determine the structural elements of a sample to be measured. The device includes: Laser source: Used to emit a laser beam. Condenser: a device for collecting the laser beam, focusing the laser beam onto the movable stage, setting the focal plane of the condenser to an initial position, and controlling the focal plane to move from the initial position to at least the bottom surface of the sample to be measured during the measurement process. Movable stage: A stage for supporting a sample to be measured, which can be moved in a plane perpendicular and / or parallel to the optical axis of the collector. The axial direction of the structure of the sample to be measured is parallel to the optical axis, and the sample to be measured is located in a position corresponding to the focal region of the laser beam. Detection module: for receiving and collecting the specific Raman scattering signals that return after the measured sample scatters the laser beam, and determining the structural elements of the measured sample based on the measurement results.

[0007] In one embodiment, the apparatus further comprises: Adjustable aperture: blocks a portion of the Raman scattering signal so that a signal corresponding to a focal region in the Raman scattering signal enters the detection module.

[0008] In one embodiment, the concentrator includes: Adjustable focal length condenser: Adjust its own focal length during the measurement process so that the focal plane moves at least from the initial position to the bottom surface of the sample to be measured.

[0009] In one embodiment, the concentrator includes a movable concentrator: Movable collector: capable of moving away from or towards the sample to be measured along a first direction, the first direction being parallel to the main optical axis. During the measurement process, the movable collector approaches the measured sample along a first direction such that the focal plane moves from an initial position to at least a bottom surface of the measured structure. The movable collector includes an optical microscope, and the main axis of the optical path is the optical axis of the objective lens of the optical microscope.

[0010] In one embodiment, the structural elements include at least one of the following: depth of the measured structure, surface roughness of the measured structure, wall roughness of the measured structure, rate of change of inner diameter of the measured structure, element distribution of the measured structure, defect distribution of the measured structure, stress distribution of the measured structure, surface crystallinity of the measured structure.

[0011] In one embodiment, a method for determining a structural element of a measured structure based on a measurement includes: A scan curve corresponding to the focal plane is determined based on the signal strength of each measurement and a corresponding first distance that the focal plane has moved relative to the movable stage. A plurality of feature points in the scan curve and a first distance corresponding to each feature point are determined. A structural element of the measured structure is determined based on a Raman scattering model corresponding to the measured structure and / or a reference sample database, each feature point and the corresponding first distance. Here, the Raman scattering model is created based on rules for the reflection and / or scattering Raman signal of the laser beam by a structure that matches the measured structure, and parameters of the reference sample database are determined based on rules for the reflection and / or scattering Raman signal of the laser beam by a structure that matches the measured structure.

[0012] In one embodiment, a method for determining a structural element of a measured structure based on a Raman scattering model corresponding to the measured structure and / or a reference sample database, each feature point and a corresponding first distance includes: A bottom maximum point and a top minimum point are determined from among the plurality of feature points based on a Raman scattering model corresponding to the measured structure and / or a reference sample database. A depth of the measured structure is determined based on a first distance corresponding to the maximum point of the bottom surface and the minimum point of the top surface, respectively.

[0013] In one embodiment, a method for determining a structural element of a measured structure based on measurements includes at least one of the following: Based on the local intensity of the measurement signal, the surface roughness and / or wall roughness of the measured structure is determined. Based on the type of signal of the measurement, the elemental distribution of the measured structure is determined. Based on the signal range, relative intensity, and offset of the measurements, one or more of the defect distribution, stress distribution, and surface crystallinity of the measured structure are determined.

[0014] In another embodiment of the present disclosure, a method for non-destructive in-situ measurement of high complexity structures based on Raman spectroscopy is provided and applied to the measurement device described above. This use includes: The sample to be measured is fixed to a movable stage, and the axial direction of the structure of the sample to be measured is made parallel to the main optical axis of the optical component. The laser light source is controlled to emit a laser beam to the sample to be measured. The optical component is controlled so that a focal plane of the optical component is at an initial position on the movable stage. The movable stage is moved in a plane perpendicular to the main optical axis to bring the position of the structure to be measured into coincidence with the focal region of the laser beam. During the measurement, the optical components are controlled such that the focal plane moves from an initial position to at least the bottom surface of the structure to be measured. The measurement module is controlled to collect returning Raman scattering signals from the measured sample scattering the laser beam and to determine structural elements of the measured structure based on the measurements.

[0015] In one embodiment, the method includes the steps of: The aperture of the adjustable iris is set to block out parts of the Raman scattering signal other than the signal corresponding to the focal region, so that only the signal corresponding to the focal region enters the measurement module.

[0016] In another embodiment, the method includes: After the measurement of the current measurement structure is completed, the movable stage is controlled to move so that the next measurement structure is positioned in the focal region of the laser beam, and the measurement of the next measurement structure is performed.

[0017] In another embodiment, the structural element includes any of the following: Depth of the measured structure, surface roughness of the measured structure, wall roughness of the measured structure, inner diameter change rate of the measured structure, element distribution of the measured structure, defect distribution of the measured structure, stress distribution of the measured structure, surface crystallinity of the measured structure.

[0018] In another embodiment, a method for determining a structural element of a measured structure based on a measurement result includes the steps of: A scan curve corresponding to the focal plane is determined based on the signal strength of each measurement and the corresponding first distance that the focal plane has moved relative to the movable stage. A plurality of characteristic points in the scan curve and a first distance corresponding to each characteristic point are determined. A structural element of the measured structure is determined based on a Raman scattering model corresponding to the measured structure and / or a reference sample database, each feature point, and the corresponding first distance. A Raman scattering model is developed using the laws of reflected and / or scattered Raman signals from a laser beam based on a structure that matches the measured structure. The parameters of the reference sample database are determined using the laws of reflected and / or scattered Raman signals of a laser beam based on structures that match the measured structure.

[0019] In another embodiment, a method for determining a structural element of a measured structure includes: A bottom maximum point and a top minimum point are determined from among the plurality of feature points based on a Raman scattering model corresponding to the measured structure and / or a reference sample database. A depth of the measured structure is determined based on a first distance corresponding to the maximum point of the bottom surface and the minimum point of the top surface.

[0020] In another embodiment, a method for determining a structural element of a measured structure based on measurements includes the steps of: Based on the local intensity of the measurement signal, the surface roughness and / or wall roughness of the measured structure is determined. Based on the type of signal of the measurement, the elemental distribution of the measured structure is determined. Based on the signal range, relative intensity, and offset of the measurements, one or more of the defect distribution, stress distribution, and surface crystallinity of the measured structure are determined.

[0021] An embodiment of the present invention provides an apparatus and method for non-destructive in-situ measurement of high-complexity structures based on Raman spectroscopy. This technique uses micro-Raman spectroscopy to rapidly, non-destructively and precisely measure the structural elements of periodic arrays of high-complexity structures at the wafer level, and evaluate their structure, composition, defects, stress, etc. This enables rapid, non-destructive evaluation of processing quality and microstructural characteristics, providing a basis for improving process yields, optimizing process conditions, and analyzing structures and manufacturing monitoring.

[0022] Other features and aspects of the present disclosure will become apparent from the following detailed description of the embodiments taken in conjunction with the drawings. [Brief description of the drawings]

[0023] [Figure 1] 1 shows the structure of an apparatus for non-destructive in situ high complexity structure measurement using Raman spectroscopy according to one embodiment of the present invention. [Diagram 2] 1 shows the structure of an apparatus for non-destructive in situ high complexity structure measurement using Raman spectroscopy according to one embodiment of the present invention. [Diagram 3]1 shows the optical path of an apparatus for non-destructive in situ high complexity structure measurement using Raman spectroscopy according to one embodiment of the present invention. [Figure 4] 1 shows a three-dimensional structure of an apparatus for non-destructive in situ high-complexity structure measurement using Raman spectroscopy based on one embodiment of the present invention. [Diagram 5] 1 shows a flowchart of a method for non-destructive in situ high complexity structure measurement by Raman spectroscopy according to one embodiment of the present invention. [Figure 6] 1 shows a scan curve in a non-destructive in situ high complexity structure measurement method using Raman spectroscopy according to one embodiment of the present invention. [Figure 7A] 1 illustrates a non-destructive in situ high complexity structure measurement process using Raman spectroscopy according to one embodiment of the present invention. [Figure 7B] 1 illustrates a non-destructive in situ high complexity structure measurement process using Raman spectroscopy according to one embodiment of the present invention. [Figure 7C] 1 illustrates a non-destructive in situ high complexity structure measurement process using Raman spectroscopy according to one embodiment of the present invention. [Figure 8] 1 shows a scan curve in a non-destructive in situ high complexity structure measurement method using Raman spectroscopy according to one embodiment of the present invention. [Figure 9] 1 shows a fitting curve of actual structure depth and Raman measurement value in a non-destructive in situ high complexity structure measurement method using Raman spectroscopy based on one embodiment of the present invention. [Figure 10] 1 shows a scan curve for a method for non-destructive in situ compositional analysis of high complexity structures using Raman spectroscopy according to one embodiment of the present invention. [Figure 11] 1 shows the execution flow of computer readable code for non-destructive in situ Raman measurement of high complexity structures according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] Various exemplary embodiments, features and aspects of the present invention are described in detail below with reference to the accompanying drawings. Identical reference numerals in the accompanying drawings indicate elements having the same or similar functions. Although there are various aspects of the embodiments shown in the accompanying drawings, the accompanying drawings are not necessarily drawn to scale unless specifically indicated.

[0025] The word "exemplary" herein means "serving as an example, embodiment, or illustration." Any embodiment described as "exemplary" is not necessarily to be construed as superior or better than other embodiments.

[0026] In addition, in order to better explain the present invention, a number of specific details are provided in the following specific embodiments. It should be understood by those skilled in the art that the present invention can be implemented without the specific details. In some embodiments, detailed descriptions of methods, means, components and circuits that are well known to those skilled in the art are omitted, and are made to emphasize the gist of the present invention.

[0027] In order to solve the technical problems in the related art, the embodiment of the present invention provides a non-destructive in-situ high-complexity structure measurement device and method based on Raman spectroscopy. The device and method are based on Raman spectroscopy and enable rapid non-destructive and precise measurement of the structural elements of periodic arrays of wafer-level high-complexity structures, which helps to non-destructively evaluate the processing quality and microstructural characteristics efficiently and at low cost. It also improves the process yield rate, provides a basis for optimizing process conditions, and provides a basis for structure analysis and manufacturing monitoring.

[0028] 1 and 2 show a schematic diagram of the structure of a non-destructive in-situ high-complexity structure measurement apparatus based on Raman spectroscopy according to an embodiment of the present invention. As shown in FIG. 1, the apparatus includes the following elements: a laser source 10, a collector 30, a movable stage 40 and a detection module 50. The apparatus is used to measure structural elements such as high-complexity microstructures 70 on a sample 60. High-complexity microstructures are hole-like structures with depth-to-width ratios of more than 5:1 and may be 1 micrometer or less in depth. For example, the structures to be measured are wafer-level high-complexity silicon vias with depth-to-width ratios of 5:1, 20:1, or 100:1.

[0029] The laser light source 10 emits a laser beam L1.

[0030] The collector 30 collects the laser beam L1 and focuses it above the movable stage 40 so that the focal plane of the collector 30 is at an initial position, and is controlled so that the focal plane moves from the initial position to at least the bottom surface of the measured structure 70 during measurement.

[0031] The movable stage 40 supports the sample 60 and allows it to move in a plane perpendicular and / or parallel to the main optical axis of the collector, such that the axial direction of a measured structure 70 in the sample 60 is parallel to the main optical axis, and the measured structure 70 is in a position corresponding to the focal region of the laser beam.

[0032] The detection module 50 collects a specific Raman scattering signal R that returns after the sample 70 is scattered into the laser beam L1, and determines the structural elements of the measured structure 70 based on the measurement results.

[0033] In this embodiment, the structural element can include parameters indicating structural features of the measured structure. The structural element may include at least one of the following: depth of the measured structure, surface roughness of the measured structure, wall roughness of the measured structure, inner diameter change rate of the measured structure, element distribution of the measured structure, defect distribution of the measured structure, stress distribution of the measured structure, and surface crystallinity of the measured structure. Those skilled in the art can set the structural element according to actual needs, and the present invention is not limited thereto.

[0034] In this embodiment, the detection module 50 can be opened at least synchronously with the laser light source 10, enabling the detection module 50 to acquire Raman scattering signals in a timely manner, and avoiding the Raman scattering signals not being collected when the focal plane is at the initial position due to reasons such as a delay in the opening timing of the detection module 50 or an erroneous operation before measurement causing the focal plane to be already between the initial position and the movable stage.

[0035] In this embodiment, the detection module 50 can also determine, based on the collector 30's own recordings, the distance that the focal plane corresponding to each collected Raman scattering signal R moves towards the movable stage or the distance between the focal plane corresponding to the Raman scattering signal R and the movable stage, thereby allowing the structural elements of the measured structure 70 to be determined based on the measurements and the distances corresponding to each measurement.

[0036] In this embodiment, the structural elements of the measured structure 70 may be analyzed and determined by the detection module, or may be determined by another processor or the like based on the measurement results and the distances corresponding to each measurement result, but the present invention is not limited thereto.

[0037] In this embodiment, the measurement range of the Raman scattering signal performed by the measurement module can be set based on the material of the measured structure, etc. Based on the estimated depth or design depth of the measured structure, the monitoring or recording range of the focal plane movement distance can be set. The movement detection range is greater than the target depth h, and the movement detection range can be 2h in order to collect specific Raman scattering signals corresponding to the top and bottom surfaces of the measured structure. Therefore, when the surface of the movable stage is set as the movement distance of the focal plane being zero, the movement detection range can be set to [-0.5h, 1.5h], [-1.5h, 1.5h], etc. Based on the measurement requirements of the measured structure, the wavelength of the laser beam emitted from the laser light source can be set. For example, when the measured structure is a silicon via with a depth of about 100 μm, the wavelength of the laser beam is set to 532 nm, and the measurement range of the Raman scattering signal of the measurement module is set to a Raman shift of 500 cm. -1 ~550cm -1 The movement detection range can be -250 μm to +250 μm. Those skilled in the art can set the measurement range, the movement detection range, and the wavelength of the laser beam according to the measurement needs, and the present invention is not limited thereto.

[0038] In one embodiment, the apparatus may include an adjustable aperture 20, as shown in Figure 2, which blocks a portion of the Raman scattering signal R, allowing a signal R1 corresponding to the focal region to enter the measurement module 50.

[0039] FIG. 3 shows a schematic diagram of the optical path of the non-destructive in-situ high-complexity structure measurement apparatus based on Raman spectroscopy according to an embodiment of the present invention. In this embodiment, as shown in FIG. 3, a signal R1 of a part of the Raman scattering signal R passes through the collector 30 and enters the measurement module 50 after passing through the aperture diameter of the adjustable aperture 20. Meanwhile, a signal R2 of another part of the Raman scattering signal R passes through the collector 30 but does not enter the measurement module 50 due to the blocking of the adjustable aperture 20. The adjustable aperture 20 is disposed in the optical path between the measurement module 50 and the collector 30. The adjustable aperture is an adjustable confocal pinhole aperture, and the size of the aperture aperture can be adjusted according to the actual blocking needs. In general, the smaller the structural feature to be measured, the smaller the aperture diameter of the adjustable aperture used during measurement, and the better the measurement accuracy. The present invention does not impose a limitation thereon. As a result, by setting the adjustable aperture 20, the spatial resolution in the main axis direction of the optical path of the apparatus can be improved.

[0040] In one embodiment, the collector 30 includes an adjustable collector with an adjustable focal length. The adjustable collector adjusts its focal length during measurement so that the focal plane moves from an initial position to at least the bottom surface of the measured structure. The adjustable collector or the measurement module can determine the moving distance of the focal plane based on the change in focal length. Thus, the adjustable collector is used to achieve the adjustment of the focal plane position to enable measurement of the measured structure.

[0041] In one embodiment, the collector 30 includes a movable collector that can move away from or towards the movable stage 40 along a first direction, the first direction being parallel to the main optical path axis. During measurement, the movable collector moves towards the movable stage 40 along the first direction, such that the focal plane moves from an initial position to at least the bottom surface of the measured structure 70.

[0042] In this embodiment, the movable condenser includes an optical microscope, and the main axis of the optical path is the optical axis of the objective lens of the optical microscope. The magnification of the objective lens can be set according to the measurement needs of the structure to be measured. For example, when the structure to be measured is a silicon through hole, the magnification of the objective lens can be set to 10x. A person skilled in the art can set the magnification of the objective lens according to the measurement needs, and the present invention is not limited thereto.

[0043] In this embodiment, as shown in Figure 4, a schematic diagram of the three-dimensional structure of the non-destructive in-situ high-complexity structure measurement device based on Raman spectroscopy according to the present invention is shown. As shown in Figure 4, the focal area of ​​the laser beam L1 refers to the area irradiated on the surface of the measured sample. The closer the size of the focal area is to the size of the measured structure 70, the more accurate the structural elements of the measured structure are.

[0044] FIG. 5 shows a flow chart of the non-destructive in-situ high-complexity structure measurement method based on Raman spectroscopy according to the present invention. As shown in FIG. 5, the method includes steps S11 to S16. The method uses the non-destructive in-situ high-complexity structure measurement device based on Raman spectroscopy provided by the embodiment of the present invention to realize non-destructive measurement of the measured structure. Hereinafter, the method provided by the embodiment of the present invention will be described with reference to FIG. 1 to FIG. 5.

[0045] In step S 11 , the sample 60 to be measured is fixed to the movable stage 40 , and the axial direction of the structure 70 to be measured in the sample 60 to be measured is made parallel to the main optical axis Z of the collector 30 .

[0046] In step S12, the laser light source 10 is controlled to emit a laser beam L1 to the sample 60 to be measured.

[0047] In step S13, the condenser 30 is controlled to place the focal plane of the condenser 30 at an initial position above the movable stage 40.

[0048] In this embodiment, as shown in FIG. 4, the focal plane of the condenser 30 can move away from or towards the movable stage 40 along the optical path main axis Z or a direction parallel to the optical path main axis Z. If the condenser is an adjustable condenser, the position of the focal plane can be directly adjusted by adjusting the focal length of the adjustable condenser. If the condenser is an optical microscope (i.e., a movable condenser), in the process of adjusting the optical microscope to place the focal plane of the laser beam L1 at the initial position, any of the following methods can be used: adjusting the object distance of the optical microscope itself, or moving the entire optical microscope to move the objective lens closer to or further away from the movable stage 40, so that "the focal plane of the laser beam L1 is placed at the initial position".

[0049] In step S14, the movable stage 40 is moved in a plane perpendicular to the optical path main axis Z so that the position of the measurement target structure 70 coincides with the focal region of the laser beam L1.

[0050] In this embodiment, as shown in FIG. 4, the movable stage 40 translates on the XY-axis plane (that is, the plane perpendicular to the optical path main axis Z) to change the relative positional relationship between the measurement target structure 70 and the focal region of the laser beam L1.

[0051] In one embodiment, if the apparatus includes an adjustable aperture 20, the following steps may be added before performing step S15: adjust the aperture diameter of the adjustable aperture 20 to block signals R2 other than the signal R1 corresponding to the focal region of the Raman scattering signal R, so that the signal R1 corresponding to the focal region of the Raman scattering signal R is incident on the measurement module 50.

[0052] In step S15, the collector 30 is controlled during the measurement so that the focal plane of the collector 30 moves from the initial position to at least the bottom surface of the structure 70 to be measured.

[0053] In step S16, the measurement module 50 collects Raman scattering signals scattered by the laser beam L1 from the measured sample 60 during measurement, and determines structural elements of the measured structure 70 based on the collected measurement results.

[0054] In one embodiment, the measurement results may include a signal intensity of the Raman scattering signal, and step S16 performed by the measurement module 50 may include: determining a scan curve corresponding to the focal plane based on the signal intensity of each measurement result and a first distance that the movable stage moves toward the corresponding focal plane; determining a plurality of feature points of the scan curve and a first distance corresponding to each feature point; and determining a structural element of the measured structure based on a Raman scattering model and / or a reference sample database corresponding to the measured structure, each feature point and its corresponding first distance.

[0055] Here, the Raman scattering model is created based on the rules for the reflection and / or scattering Raman signal of the laser beam when a structure corresponding to the measured structure is detected; parameters of the reference sample database are determined based on the rules for the reflection and / or scattering Raman signal of the laser beam when a structure corresponding to the measured structure is detected.

[0056] In an embodiment, before identifying the plurality of feature points in the scan curve and the first distances corresponding to each of the feature points, the scan curve can be pre-processed, which can include a smoothing process, a fitting process, or both, to improve the accuracy of the identified structuring element.

[0057] In this embodiment, the patterns of the reflected and / or scattered Raman signals of the laser beam can be predicted based on different types of measured structures (i.e. structures), and the Raman scattering models of the predicted scan curves corresponding to the different types of measured structures can be simulated. Based on this model, the structure elements can be determined by comparing with the actually generated scan curves. Alternatively, the patterns of the reflected and / or scattered Raman signals of the laser beam can be predicted based on different types of measured structures, the parameter features of the predicted scan curves of the different types of measured structures can be calculated, and a reference sample database can be constructed, and the parameter features of the predicted scan curves recorded in the reference sample database can be compared with the actual scan curves to determine the structure elements.

[0058] In some embodiments, identifying structural elements of the measured structure based on a Raman scattering model and / or a reference sample database corresponding to the measured structure, each feature point, and the corresponding first distance may include: A bottom maximum point and a top minimum point are identified from among the plurality of feature points based on a Raman scattering model corresponding to the measured structure and / or a reference sample database. The depth of the measured structure is measured based on a first distance corresponding to the maximum point of the bottom surface and the minimum point of the top surface, respectively.

[0059] For example, FIG. 6 shows a schematic diagram of a scan curve in a non-destructive in-situ high complexity structure measurement method using Raman spectroscopy according to an embodiment of the present invention. Based on the signal intensity of each Raman scattering signal and the first distance of the focal plane movement detected (or recorded by the collector), the measurement module 50 identifies a scan curve Q for the first distance and signal intensity corresponding to the focal plane shown in FIG. 6. Then, based on the corresponding Raman scattering model and / or reference sample database, the bottom maximum point B and top minimum point A of the scan curve Q, as well as the respective movement distances S1=-136.1 and S2=118.5, can be identified to determine the depth H of the measured structure 70=|S2-S1|=|118.5-(-136.1)|=254.6 μm.

[0060] 7A to 7C show schematic diagrams of a non-destructive in-situ high complexity structure measurement process by Raman spectroscopy according to an embodiment of the present invention. To explain the measurement process of the measured structure according to an embodiment of the present invention, the following description will be made with reference to FIGS. 7A to 7C. In the process of moving the focal plane, the laser beam L1 is focused by the collector 30. As shown in FIG. 7A, when the focal plane approaches the upper surface of the measured sample 60, the light spot of the laser beam L1 projected on the upper surface (i.e., the focal area) coincides with the size of the measured structure 70, and the laser beam L1 is completely incident on the measured structure 70. The Raman scattering signal gradually decreases and disappears in the area of ​​the measured structure 70 corresponding to the upper surface of the measured sample 60, and the minimum value point A of the top surface as shown in FIG. 6 appears on the scan curve. As shown in FIG. 7B, when the focal plane gradually descends and the laser beam L1 is irradiated on the wall surface of the measured structure 70 again, the signal intensity of the reflected light and the Raman scattering signal increases. 7C, when the focal plane approaches the bottom surface of the measured structure 70, the entire bottom surface of the measured structure 70 is irradiated with the laser beam L1, and a maximum point B on the bottom surface appears on the scan curve. The difference in distance between the maximum point B on the bottom surface and the minimum point A on the top surface indicates the depth of the measured structure 70.

[0061] In this embodiment, when the measured sample contains multiple measured structures, the array scanning method can be used to measure some or all of the multiple measured structures. The array scanning includes the following steps: after the measurement process of Figures 7A to 7C completes the measurement of each measured structure, adjust the relative positions of the movable stage 40 and the condenser 30 in the plane perpendicular to the optical path main axis, control the condenser 30 to move the focal plane away from the movable stage 40, and return the focal plane of the laser beam L1 to the initial position, so that the focusing area reaches the position of the next measured structure, and then repeat the measurement process of Figures 7A to 7C to complete the measurement of all measured structures.

[0062] In this embodiment, when the sample to be measured includes multiple measurement structures, the measurement structures can be measured partially or entirely. The measurement of the partial measurement structures includes a usage of measuring multiple measurement structures at intervals (i.e., after measuring the current measurement structure, the next measurement structure is another measurement structure that is one interval away from the already measured measurement structure) and a usage of measuring only a specified measurement structure from the multiple measurement structures (i.e., a usage of measuring multiple measurement structures specified from the multiple measurement structures). The measurement can be realized by setting the position of the specified measurement structure in advance. A person skilled in the art can set the partial measurement of multiple measurement structures based on actual needs. The present invention does not set any restrictions on this.

[0063] When the measured sample includes multiple measured structures, the apparatus can record the movement distances of the movable stage 40 in the X-axis and Y-axis directions between the different measured structures, and measure the relative positional relationship between the multiple measured structures based on the movement distances in the X-axis and Y-axis directions.

[0064] In addition, when the measured sample includes multiple measured structures, the apparatus can calculate the structural elements of each measured structure and then perform a uniformity evaluation of the structural elements, for example, a depth uniformity evaluation based on the depth of each measured structure.

[0065] For structures with periodic unevenness on the sidewall, the wall roughness can be accurately measured using the Raman scattering model and / or the reference sample database. However, for structures with complex structures and very high depth-to-width ratios, the Raman scattering model and / or the reference sample database may be complicated, and standard samples can be used to build the Raman scattering model, and big data methods such as machine learning can be used to achieve high-precision fitting and precise analytical measurements.

[0066] For example, FIG. 8 shows a schematic diagram of a scan curve in a non-destructive in-situ high complexity structure measurement method using Raman spectroscopy according to an embodiment of the present invention. As shown in FIG. 8, when the depth-to-width ratio of the measured structure is about 10:1, the scan curve Q' shown in FIG. 8 is obtained. Based on the Raman scattering model and / or the reference sample database, each feature point and the corresponding first distance can be used to identify the structural element. For example, when the maximum point B of the bottom surface and the minimum point A of the top surface of the scan curve Q' correspond to the top surface and the bottom surface of the measured structure, the first distances are S1=-145 μm and S2=130 μm, so that the depth H of the measured structure 70 can be determined as H=|S2-S1|=|130-(-145)|=275 μm. Furthermore, other structural elements of the measured structure can be further identified using C1, C2, and C3.

[0067] The present invention further shows a method of analyzing the conversion relationship between the depth of the measured structure and the Raman spectroscopy measurement value in the process of performing non-destructive in-situ measurement of a highly complex structure using Raman spectroscopy. After measuring a number of standard structure samples (whose composition, structure shape, and geometric dimensions are known, i.e., the structural elements are known) with different depths, the obtained Raman measurement value is fitted to the depth of the standard structure to obtain the conversion relationship between the measurement value and the dimension of the standard structure. In the embodiment of the present invention, after performing Raman measurement on a standard structure having a known shape of 80 μm to about 400 μm, the Raman spectroscopy value (x) obtained based on the measurement result and the actual known structure depth (y) are fitted to derive a conversion formula. The conversion formula is as follows: actual known structure depth y = Raman spectroscopy value x * 1.27 - 11.55 (μm). A linear fitting diagram is shown in FIG. 9. For analysis and measurement data of similar complex structures, this method can further optimize the fitting result through big data reinforcement learning, improving analysis accuracy and calculation efficiency. The fitting time scale is from 1 µs to several microseconds, and this method can realize ultrafast non-destructive in situ measurements on the order of sub-microseconds in practical applications.

[0068] In one embodiment, determining the structural elements of the measured structure based on the measurement results may include the following steps: determining the surface roughness and / or wall roughness of the measured structure based on the local intensity of the measurement signal.

[0069] For example, the measurement module 50 can determine a scan curve Q for the first distance and signal intensity corresponding to the focal plane shown in FIG. 6 based on the signal intensity of each Raman scattering signal and the first distance of the focal plane movement detected (or recorded by the collector), and obtain roughness information of the sample surface by analyzing minute peak distances in the curve.

[0070] In another embodiment, determining structural elements of the measured structure based on the measurement results may include the following steps: determining the element distribution of the measured structure based on the signal type of the measurement results, or determining one or more of the defect distribution, stress distribution, and surface crystallinity of the measured structure based on the signal section, relative volume, and shift amount of the measurement results.

[0071] For example, as shown in FIG. 10, the measurement module 50 determines a scan curve for the first distance and relative peak position corresponding to the focal plane shown in FIG. 10 based on the signal peak position of each Raman scattering signal and the first distance of the focal plane movement detected (or recorded by the collector), and then determines that the different characteristic peak positions in the scan curve correspond to the material composition based on the Raman scattering signal characteristic value of the corresponding composition and / or the reference sample database, and obtains the distribution status of the material along the first distance. Similarly, the signal peak position analysis can be changed to the half-width method of the signal to realize the analysis of the surface crystallinity and defect distribution of the structure. Also, the signal peak position analysis can be changed to the shift amount analysis of the signal relative to the standard material peak to realize the surface stress distribution analysis of the structure.

[0072] Although the above embodiment illustrates the non-destructive in-situ high-complexity structure measurement device and its use based on Raman spectroscopy, those skilled in the art will understand that the present invention is not limited thereto. In fact, users can flexibly configure modules and steps according to their individual preferences and actual application scenarios as long as they are in line with the technical solutions of the present invention.

[0073] In some embodiments, the functions of the device or modules included therein provided in the embodiments of the present invention can be used to perform the usage described in the above usage examples, and the specific implementations thereof are to be referred to the description of the above usage examples, which are not repeated here for the sake of brevity.

[0074] The present invention also proposes a computer readable storage medium, on which computer program instructions are stored, which are executed by a processor to realize the step of determining the structural element of the measured structure based on the measurement result in the above-mentioned use. The computer readable storage medium can be either volatile or non-volatile.

[0075] The present invention further proposes an electronic device, comprising: a processor; a memory for storing instructions executable by the processor; the processor being configured to realize, by executing the instructions stored in the memory, a step of determining a structural element of the measured structure based on the measurement results.

[0076] An embodiment of the present invention also provides a computer program product, the program product comprising a non-volatile computer readable storage medium including or having computer readable code thereon, the computer readable code being executed by a processor in an electronic device, causing the processor in the electronic device to perform the steps of determining a structural element of the measured structure based on the measurement results in the above-mentioned use.

[0077] The embodiment of the present invention further provides an execution flow of executable code for a method for non-destructive in-situ high-complexity structure measurement based on Raman spectroscopy. The executable code can detect peaks using a Python standard function scipy.signal.find_peaks(). As shown in FIG. 11, the execution flow includes steps S21 to S217. The computer-readable code provided in the embodiment of the present invention will be described below with reference to FIG. 11.

[0078] In step S21, the program retrieves data from the source document of the measurement result and calls up the first data point. The format of the source document can be .csv, .txt, or .xlsx, etc., and is not limited in the present invention.

[0079] In step S22, the program calls and checks the next data point and proceeds to step S23.

[0080] In step S23, the program compares the intensity of the currently acquired data point with the intensity of the previous data point, if the intensity of the current data point is greater than the intensity of the previous data point, it proceeds to step S24, otherwise it proceeds to step S29.

[0081] In step S24, the program compares the intensity of the current data point with the intensity of the next data point, and if the intensity of the current data point is greater than the intensity of the next data point, it proceeds to step S25, otherwise it returns to step S22.

[0082] In step S25, the program defines the current data point as a potential peak data point and proceeds to step S26.

[0083] In step S26, the program compares the peak width corresponding to the current data point of the potential peak with a default value. If the peak width is greater than the default value, the program proceeds to step S27, otherwise it returns to step S22. An example of the default value could be an abscissa difference of 10 data points.

[0084] In step S27, the current data point that is the potential peak is defined as a data point that belongs to the peak, and the process proceeds to step S28.

[0085] In step S28, the program determines whether the current data point is the last data point, and if so, proceeds to step S215, otherwise returns to step S22.

[0086] In step S29, the program compares the intensity of the current data point with the intensity of the previous data point, and if the intensity of the current data point is less than the intensity of the previous data point, it proceeds to step S210, otherwise it returns to step S22.

[0087] In step S210, the program compares the intensity of the current data point with the intensity of the next data point, and if the intensity of the current data point is less than the intensity of the next data point, it proceeds to step S211, otherwise it returns to step S22.

[0088] In step S211, the program defines the current data point as a potential valley data point and proceeds to step S212.

[0089] In step S212, the program compares the valley width of the current data point that is the potential valley with the default value. If the valley width is greater than the default value, the program proceeds to step S213, otherwise the program returns to step S22. An example of the default value could be an abscissa difference of 10 data points.

[0090] In step S213, the current data point with the valley potential is defined as a data point that belongs to the valley, and the process proceeds to step S214.

[0091] In step S214, the program determines whether the current data point is the last data point, and if so, proceeds to step S215, otherwise returns to step S22.

[0092] In step S215, the program determines whether the abscissa of the first peak is greater than the first valley, if so, it proceeds to step S216, otherwise it proceeds to step S217.

[0093] In step S216, the program calculates the distance between the first valley and the last peak after the first peak and outputs the measurement.

[0094] In step S217, the program calculates the distance between the first valley and the last peak and outputs the measurement.

[0095] Thus, each embodiment of the present invention has been described. The above description is illustrative and not restrictive. Many modifications and variations are obvious to those skilled in the art, and it can be understood that the present invention is not limited thereto. The selection of the terms of the present invention is intended to best explain the principles, practical applications, or technical improvements in the market of each embodiment, and is intended to allow other skilled in the art to understand each embodiment of the present invention.

[0096] (Additional Note) (Appendix 1) A non-destructive in-situ high-complexity structure measurement apparatus based on Raman spectroscopy, which is used to determine the structure of a sample to be measured, comprising a laser light source, a collector, a movable stage, and a detection module; A laser source is used to emit a laser beam, The condenser condenses the laser beam and focuses it above the movable stage, and the focal plane of the condenser is set at an initial position, and the focal plane is moved from the initial position to at least a bottom surface of the structure to be measured during the measurement process; The movable stage supports the sample to be measured and can move in a plane perpendicular or parallel to the optical path axis of the collector, and the axial direction of the structure of the sample to be measured is parallel to the optical path axis and is disposed at a position corresponding to the focal region of the laser beam; A measurement apparatus characterized in that the detection module is used to collect a specific Raman scattering signal that returns after the laser beam is scattered by the measured sample, and to determine structural elements of the measured sample based on the measurement results.

[0097] (Appendix 2) 2. The measurement device according to claim 1, The measurement apparatus further includes a variable aperture used to block a portion of the Raman scattering signal, allowing a signal corresponding to the focal region to be incident on the detection module.

[0098] (Appendix 3) 2. The measurement apparatus of claim 1, wherein the collector comprises a variable collector having an adjustable focal length; The variable condenser is characterized in that the focal length is adjusted during the measurement process to move the focal plane from an initial position to at least the bottom surface of the structure to be measured.

[0099] (Appendix 4) 2. The measurement device of claim 1, wherein the collector comprises a movable collector; the movable collector is movable toward or away from the movable stage along a first direction, the first direction being parallel to the optical path axis; During the measurement process, the movable collector approaches the movable stage along a first direction to move the focal plane from an initial position to at least a bottom surface of the structure to be measured; A measuring apparatus according to claim 1, wherein the movable condenser includes an optical microscope, and the optical path axis is the optical axis of an objective lens of the optical microscope.

[0100] (Appendix 5) 5. The measuring apparatus according to claim 1, wherein the structural elements include at least one of a depth, a surface roughness, a wall roughness, a variation rate of an inner diameter, an element distribution, a defect distribution, a stress distribution, and a surface crystallinity of the measured structure.

[0101] (Appendix 6) In the measurement apparatus according to claim 5, determining a structural element of the measured sample based on the measurement result comprises: determining a scan curve corresponding to the focal plane based on the signal strength of each measurement and the distance the corresponding focal plane has moved towards the movable stage; Identifying a plurality of characteristic points within the scan curve and determining a distance corresponding to each of the characteristic points; determining a structural element from each characteristic point and the corresponding distance based on a Raman scattering model corresponding to the measured structure and / or a reference sample database; A measurement apparatus characterized in that the Raman scattering model is created based on the regularity of the Raman signal when a laser beam is reflected or scattered by a structure that matches the measured structure, and the parameters of the reference sample database are determined based on the regularity of the Raman signal when a laser beam is reflected or scattered by a structure that matches the measured structure.

[0102] (Appendix 7) 7. The measurement apparatus according to claim 6, wherein determining the structural element based on the Raman scattering model and / or the reference sample database corresponding to the measured structure includes identifying a bottom maximum point and a top minimum point among the characteristic points based on the Raman scattering model and / or the reference sample database corresponding to the measured structure, and determining a depth of the measured structure based on a distance corresponding to the bottom maximum point and the top minimum point; Determining a structural element of the measured sample based on the measurement results includes: determining a surface and / or wall roughness of the measured structure based on localized intensities of the collected signals; Identifying an elemental distribution based on the type of signal; and and determining one or more of defect distribution, stress distribution, and surface crystallinity based on the range, relative volume, and shift amount of the signals.

[0103] (Appendix 8) A method for the non-destructive in situ measurement of high complexity structures based on Raman spectroscopy, the method being adapted for a measurement device according to any one of claims 1 to 7, comprising: Fixing the sample to be measured on a movable stage and aligning an axial direction of a structure to be measured in the sample parallel to an optical path axis of the collector; Controlling a laser light source to emit a laser beam to a sample to be measured; controlling the condenser to position the focal plane at an initial position above the movable stage; moving the movable stage in a plane perpendicular to the optical axis to position the structure to be measured in a focal region of the laser beam; During the measurement process, moving the focal plane from an initial position to at least a bottom surface of the structure to be measured; A measurement method for use comprising controlling a detection module to collect a specific Raman scattering signal that returns after the laser beam is scattered by the sample, and determining a structural element of the measured structure based on the measurement result.

[0104] (Appendix 9) A measurement method according to claim 8, comprising: The measurement method further includes adjusting the aperture diameter of the variable aperture to block Raman scattering signals other than the signal corresponding to the focal region, so that the signal corresponding to the focal region is incident on the detection module.

[0105] (Appendix 10) A measurement method according to claim 8, comprising: A method of measurement, comprising: after completing measurement of a current measured structure, moving a movable stage so that a next measured structure is positioned in a focal region of a laser beam, and measuring the next measured structure.

[0106] (Appendix 11) A measurement method according to any one of appendices 8 to 10, characterized in that the structural elements include at least one of the depth of the structure to be measured, the surface roughness of the structure to be measured, the wall roughness of the structure to be measured, the inner diameter variation rate of the structure to be measured, the element distribution of the structure to be measured, the defect distribution of the structure to be measured, the stress distribution of the structure to be measured, and the surface crystallinity of the structure to be measured.

[0107] (Appendix 12) 12. The measurement use method according to claim 11, wherein determining the structural element based on a measurement result comprises: determining a scan curve corresponding to the focal plane based on the signal strength of each measurement and a first distance that the corresponding focal plane has moved toward the movable stage; Identifying a plurality of characteristic points within the scan curve and determining a first distance corresponding to each characteristic point; determining a structural element of the measured structure based on a Raman scattering model corresponding to the measured structure and / or a reference sample database, each characteristic point and the corresponding first distance; Here, the Raman scattering model is created based on the regularity of the Raman signal when a laser beam is reflected or scattered by a structure that matches the measured structure, and the parameters of the reference sample database are determined based on the regularity of the Raman signal when a laser beam is reflected or scattered by a structure that matches the measured structure.

[0108] (Appendix 13) 13. The measurement method of claim 12, wherein determining a structural element of the measured structure based on a Raman scattering model and / or a reference sample database corresponding to the measured structure, each characteristic point and a corresponding first distance comprises: identifying a bottom maximum point and a top minimum point from among the plurality of characteristic points based on a Raman scattering model and / or a reference sample database corresponding to the measured structure; and determining a depth of the measured structure based on the first distance corresponding to the bottom maximum point and the top minimum point; Also, determining a structural element of the measured structure based on the measurement result includes: determining a surface roughness and / or a wall roughness of the measured structure based on the local intensity of the measurement signal; Identifying an element distribution in the measured structure based on the type of the signal of the measurement result; and determining one or more of the defect distribution, stress distribution, and surface crystallinity of the measured structure based on the signal range, relative volume, and shift amount of the measurement results.

Claims

1. A non-destructive in-situ high-complexity structure measurement apparatus based on Raman spectroscopy, which is used to determine the structure of a sample to be measured, comprising a laser light source, a collector, a movable stage, and a detection module; A laser source is used to emit a laser beam, The condenser condenses the laser beam and focuses it above the movable stage, and the focal plane of the condenser is set at an initial position, and the focal plane is moved from the initial position to at least a bottom surface of the structure to be measured during the measurement process; The movable stage supports the sample to be measured and can move in a plane perpendicular or parallel to the optical path axis of the collector, and the axial direction of the structure of the sample to be measured is parallel to the optical path axis and is disposed at a position corresponding to the focal region of the laser beam; A measurement apparatus characterized in that the detection module is used to collect a specific Raman scattering signal that returns after the laser beam is scattered by the measured sample, and to determine structural elements of the measured sample based on the measurement results.

2. 2. The measuring device according to claim 1, The measurement apparatus further includes a variable aperture used to block a portion of the Raman scattering signal, allowing a signal corresponding to the focal region to be incident on the detection module.

3. 2. The measurement apparatus of claim 1, wherein the collector comprises a variable collector having an adjustable focal length; The variable condenser is characterized in that the focal length is adjusted during the measurement process to move the focal plane from an initial position to at least the bottom surface of the structure to be measured.

4. 2. The measurement device of claim 1, wherein the collector comprises a movable collector; the movable collector is movable toward or away from the movable stage along a first direction, the first direction being parallel to the optical path axis; During the measurement process, the movable collector approaches the movable stage along a first direction to move the focal plane from an initial position to at least a bottom surface of the structure to be measured; A measuring apparatus according to claim 1, wherein the movable condenser includes an optical microscope, and the optical path axis is the optical axis of an objective lens of the optical microscope.

5. 5. A measuring apparatus according to claim 1, wherein the structural elements include at least one of a depth of the structure to be measured, a surface roughness, a wall roughness, a variation rate of an inner diameter, an element distribution, a defect distribution, a stress distribution, and a surface crystallinity.

6. 6. The measurement apparatus according to claim 5, wherein determining a structural element of the measured sample based on the measurement result comprises: determining a scan curve corresponding to the focal plane based on the signal strength of each measurement and the distance the corresponding focal plane has moved towards the movable stage; Identifying a plurality of characteristic points within the scan curve and determining a distance corresponding to each of the characteristic points; determining a structural element from each characteristic point and the corresponding distance based on a Raman scattering model corresponding to the measured structure and / or a reference sample database; A measurement apparatus characterized in that the Raman scattering model is created based on the regularity of the Raman signal when a laser beam is reflected or scattered by a structure that matches the measured structure, and the parameters of the reference sample database are determined based on the regularity of the Raman signal when a laser beam is reflected or scattered by a structure that matches the measured structure.

7. 7. The measuring apparatus according to claim 6, wherein determining the structural element based on the Raman scattering model and / or the reference sample database corresponding to the measured structure includes: identifying a bottom maximum point and a top minimum point among the characteristic points based on the Raman scattering model and / or the reference sample database corresponding to the measured structure; and determining a depth of the measured structure based on a distance corresponding to the bottom maximum point and the top minimum point; Determining a structural element of the measured sample based on the measurement results includes: determining a surface and / or wall roughness of the measured structure based on localized intensities of the collected signals; Identifying an elemental distribution based on the type of signal; and and determining one or more of defect distribution, stress distribution, and surface crystallinity based on the range, relative volume, and shift amount of the signals.

8. A method for the non-destructive in situ measurement of high complexity structures based on Raman spectroscopy, the method being adapted to a measurement device according to any one of claims 1 to 7, comprising: Fixing the sample to be measured on a movable stage and aligning an axial direction of a structure to be measured in the sample parallel to an optical path axis of the collector; Controlling a laser light source to emit a laser beam to a sample to be measured; controlling the condenser to position the focal plane at an initial position above the movable stage; moving the movable stage in a plane perpendicular to the optical axis to position the structure to be measured in a focal region of the laser beam; During the measurement process, moving the focal plane from an initial position to at least a bottom surface of the structure to be measured; A measurement method for use comprising controlling a detection module to collect a specific Raman scattering signal that returns after the laser beam is scattered by the sample, and determining a structural element of the measured structure based on the measurement result.

9. 9. A method for measuring and using a measuring device according to claim 8, comprising: The measurement method further includes adjusting the aperture diameter of the variable aperture to block Raman scattering signals other than the signal corresponding to the focal region, so that the signal corresponding to the focal region is incident on the detection module.

10. 9. A method for measuring and using a measuring device according to claim 8, comprising: A method of measurement, comprising: after completing measurement of a current measured structure, moving a movable stage so that a next measured structure is positioned in a focal region of a laser beam, and measuring the next measured structure.

11. A measurement method according to any one of claims 8 to 10, characterized in that the structural elements include at least one of the depth of the structure to be measured, the surface roughness of the structure to be measured, the wall roughness of the structure to be measured, the inner diameter variation rate of the structure to be measured, the element distribution of the structure to be measured, the defect distribution of the structure to be measured, the stress distribution of the structure to be measured, and the surface crystallinity of the structure to be measured.

12. 12. The method of claim 11, wherein determining the structural element based on a measurement result comprises: determining a scan curve corresponding to the focal plane based on the signal strength of each measurement and a first distance that the corresponding focal plane has moved toward the movable stage; Identifying a plurality of characteristic points within the scan curve and determining a first distance corresponding to each characteristic point; determining a structural element of the measured structure based on a Raman scattering model corresponding to the measured structure and / or a reference sample database, each characteristic point and the corresponding first distance; Here, the Raman scattering model is created based on the regularity of the Raman signal when a laser beam is reflected or scattered by a structure that matches the measured structure, and the parameters of the reference sample database are determined based on the regularity of the Raman signal when a laser beam is reflected or scattered by a structure that matches the measured structure.

13. 13. The measurement method according to claim 12, wherein determining a structural element of the measured structure based on a Raman scattering model and / or a reference sample database corresponding to the measured structure, each characteristic point and a corresponding first distance comprises: identifying a bottom maximum point and a top minimum point from among the plurality of characteristic points based on a Raman scattering model and / or a reference sample database corresponding to the measured structure; and determining a depth of the measured structure based on the first distance corresponding to the bottom maximum point and the top minimum point; Also, determining a structural element of the measured structure based on the measurement result includes: determining a surface roughness and / or a wall roughness of the measured structure based on the local intensity of the measurement signal; Identifying an element distribution in the measured structure based on the type of the signal of the measurement result; and determining one or more of the defect distribution, stress distribution, and surface crystallinity of the measured structure based on the signal range, relative volume, and shift amount of the measurement results.

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