Defect detection method and system, storage medium and computer equipment

Abstract

The invention discloses a defect detection method and system, a storage medium and computer equipment, and belongs to the technical field of wafer graph-free defect detection, and the method comprises the steps: obtaining first parameter information of an incident light beam and second parameter information of a wafer to be detected, the first parameter information comprises the incident light wavelength, the incident light intensity and the incident light polarization direction, and the second parameter information comprises the incident light wavelength and the incident light intensity; the second parameter information comprises distribution states of particles of various sizes on the surface of the wafer; a wafer scattered field transmission model is constructed based on the first parameter information and the second parameter information, the wafer scattered field transmission model has the characteristics of multiple channels and multiple modes, the scattered light intensity of particles of different sizes in each channel and each mode can be obtained, and the scattered light intensity distribution result and the polarized light intensity distribution result of the particles of different sizes are determined; selecting a modal combination in a wafer scattered field transmission model according to the size range of the detected particles in combination with the scattered light intensity distribution result and the polarized light intensity distribution result of the particles with various sizes; and determining element parameters required to be selected in the defect detection system based on the modal combination.

Description

Technical Field

[0001] The present application belongs to the technical field of wafer non-patterned defect detection, and specifically relates to a defect detection method and system, a storage medium, and a computer device. Background Art

[0002] In the field of semiconductor manufacturing, wafers are the basic materials of integrated circuits, and their surface quality is directly related to the performance and yield of chips. With the continuous improvement of chip integration, the requirements for the detection accuracy of wafer surface defects are becoming more and more stringent. Traditional wafer defect detection methods, such as electron microscope-based detection technology, can provide high-resolution microscopic images, but have disadvantages such as slow detection speed, damage to samples, and high equipment costs.

[0003] At the same time, optical detection methods have gradually emerged with their advantages of non-contact and fast detection speed. However, the simple optical detection methods in the early days could only capture relatively rough information on the surface of the wafer, which was difficult to meet the needs of high-precision detection. This is because there are complex and diverse particles on the surface of the wafer. These particles vary in size, ranging from nanometers to micrometers, and their distribution is affected by many factors in the manufacturing process, such as parameter fluctuations in the chemical mechanical polishing process and residues in the cleaning process. Particles of different sizes will produce completely different scattering and polarization characteristics when interacting with incident light.

[0004] Previous optical inspection systems often lacked sufficient consideration of the multi-dimensional interaction characteristics of light and particles. Most of them only focused on a single wavelength, a single polarization direction or a limited number of observation angles, and were unable to fully and accurately analyze the changes in the scattered light field caused by particles on the wafer surface. This resulted in a large number of subtle defects being missed during the inspection process, and misjudgments often occurred. Summary of the invention

[0005] In view of this, the present application provides a defect detection method and system, a storage medium, and a computer device, the main purpose of which is to increase the types of defect detection and broaden the scope of defect detection.

[0006] In order to achieve the above objectives, this application mainly provides the following technical solutions:

[0007] In a first aspect of the present application, a defect detection method is provided, comprising:

[0008] Acquire first parameter information of the incident light beam and second parameter information of the wafer to be tested, wherein the first parameter information includes the wavelength, intensity and polarization direction of the incident light, and the second parameter information includes the distribution state of particles of various sizes on the surface of the wafer;

[0009] A wafer scattering field transmission model is constructed based on the first parameter information and the second parameter information. The wafer scattering field transmission model has multi-channel and multi-modal characteristics, and can obtain the scattered light intensity of particles of different sizes in each channel and each mode, so as to determine the scattered light intensity distribution results and polarized light intensity distribution results of particles of each size;

[0010] Selecting a mode combination in the wafer scattered field transmission model according to the size range of the particles to be tested and combining the scattered light intensity distribution results and the polarized light intensity distribution results of the particles of each size;

[0011] The component parameters required for use in the defect detection system are determined based on the modal combination.

[0012] Optionally, the defect detection method further includes:

[0013] The component parameters for the defect detection system determined according to the modal combination are substituted into the wafer scattered field transmission model to determine the particle size detection range of each channel.

[0014] Optionally, the defect detection method further includes:

[0015] The detection level of each channel was verified using a standard particle calibration film experiment.

[0016] Optionally, the use of a standard particle verification sheet to verify the detection level of each channel includes:

[0017] When the actual detection result does not match the theoretical expected result, return to the step of determining the component parameters required to be selected in the defect detection system based on the modal combination, and optimize the component parameters required to be selected in the defect detection system again.

[0018] Optionally, the component parameters required to be selected in the defect detection system include scattering angle beam splitter parameters, polarization beam splitter parameters and aperture beam splitter parameters.

[0019] Optionally, the second parameter information also includes a distribution state of pits on the wafer surface.

[0020] Optionally, the second parameter information also includes a distribution state of protrusions on the wafer surface.

[0021] Optionally, the second parameter information also includes a distribution state of scratches on the wafer surface.

[0022] Optionally, the second parameter information also includes the refractive index of the wafer to be tested.

[0023] Optionally, the second parameter information also includes an absorption coefficient of the wafer to be tested.

[0024] In a second aspect of the present application, a defect detection system is provided, comprising a plurality of detection channels, wherein the modal combination of each of the detection channels is determined according to any of the above-mentioned defect detection methods.

[0025] Optionally, the defect detection system includes a laser light source and a wafer to be tested, the laser light source is arranged toward the wafer to be tested, the laser light source is used to emit an incident light beam, an objective lens is arranged within the scattering angle range of the wafer to be tested, the objective lens is used to collect light scattered from the surface of the wafer to be tested, a scattering angle spectrometer is arranged on the downstream side of the objective lens along the light path direction, the scattering angle spectrometer is used to split the light collected from the objective lens into a first detection channel and a second detection channel, the first detection channel includes a first transmission lens group, a first polarization filter, a first aperture and a first detector arranged in sequence along the light path direction, and the second detection channel includes a second transmission lens group, a second polarization filter, a second aperture and a second detector arranged in sequence along the light path direction.

[0026] Optionally, the defect detection system includes a laser light source and a wafer to be tested, the laser light source is arranged toward the wafer to be tested, the laser light source is used to emit an incident light beam, an objective lens is arranged within the scattering angle range of the wafer to be tested, the objective lens is used to collect light scattered from the surface of the wafer to be tested, a scattering angle beam splitter is arranged on the downstream side of the objective lens along the light path direction, the scattering angle beam splitter is used to split the light collected from the objective lens into a first light path and a second light path, a first beam splitter is arranged on the propagation path of the first light path, the first beam splitter is used to split the light propagating on the first light path into a first detection channel and a third detection channel, the first detection channel includes a detection channel along the light path direction according to the detection angle of the first light path. The first detection channel comprises a first transmission mirror group, a first polarization filter, a first diaphragm and a first detector which are sequentially arranged along the light path direction; the third detection channel comprises a third transmission mirror group, a third polarization filter, a third diaphragm and a third detector which are sequentially arranged along the light path direction; a second beam splitter is arranged on the propagation path of the second light path; the second beam splitter is used to divide the light propagating on the second light path into a second detection channel and a fourth detection channel; the second detection channel comprises a second transmission mirror group, a second polarization filter, a second diaphragm and a second detector which are sequentially arranged along the light path direction; the fourth detection channel comprises a fourth transmission mirror group, a fourth polarization filter, a fourth diaphragm and a fourth detector which are sequentially arranged along the light path direction.

[0027] Optionally, the defect detection system includes a laser light source and a wafer to be tested, the laser light source is arranged toward the wafer to be tested, the laser light source is used to emit an incident light beam, an objective lens is arranged within the scattering angle range of the wafer to be tested, the objective lens is used to collect light scattered from the surface of the wafer to be tested, a scattering angle beam splitter is arranged on the downstream side of the objective lens along the light path direction, the scattering angle beam splitter is used to split the light collected from the objective lens into a first light path and a second light path, a first polarization beam splitter is arranged on the propagation path of the first light path, the first polarization beam splitter is used to split the light propagating on the first light path into a first detection channel and a third detection channel, the The first detection channel includes a first transmission mirror group, a first aperture and a first detector which are sequentially arranged along the direction of the optical path; the third detection channel includes a third transmission mirror group, a third aperture and a third detector which are sequentially arranged along the direction of the optical path; a second polarization beam splitter is arranged on the propagation path of the second optical path; the second polarization beam splitter is used to divide the light propagating on the second optical path into a second detection channel and a fourth detection channel; the second detection channel includes a second transmission mirror group, a second aperture and a second detector which are sequentially arranged along the direction of the optical path; and the fourth detection channel includes a fourth transmission mirror group, a fourth aperture and a fourth detector which are sequentially arranged along the direction of the optical path.

[0028] Optionally, the defect detection system includes a laser light source and a wafer to be tested, the laser light source is arranged toward the wafer to be tested, the laser light source is used to emit an incident light beam, an objective lens is arranged within the scattering angle range of the wafer to be tested, the objective lens is used to collect light scattered from the surface of the wafer to be tested, a scattering angle beam splitter is arranged on the downstream side of the objective lens along the light path direction, the scattering angle beam splitter is used to split the light collected from the objective lens into a first light path and a second light path, an aperture beam splitter is arranged on the propagation path of the first light path, the aperture beam splitter is used to split the light propagating on the first light path into a third light path and a fourth light path, a first polarization beam splitter is arranged on the propagation path of the third light path, the first polarization beam splitter is used to split the light propagating on the third light path into a first detection channel and a second detection channel, the first detection channel comprises a first transmission mirror group, a first aperture and a first detector which are sequentially arranged along the light path direction, and the second The detection channel includes a second transmission mirror group, a second aperture and a second detector which are sequentially arranged along the optical path direction; a third polarization beam splitter is arranged on the propagation path of the fourth optical path; the third polarization beam splitter is used to divide the light propagating on the fourth optical path into a fifth detection channel and a sixth detection channel; the fifth detection channel includes a fifth transmission mirror group, a fifth aperture and a fifth detector which are sequentially arranged along the optical path direction; the sixth detection channel includes a sixth transmission mirror group, a sixth aperture and a sixth detector which are sequentially arranged along the optical path direction; a second polarization beam splitter is arranged on the propagation path of the second optical path; the second polarization beam splitter is used to divide the light propagating on the second optical path into a third detection channel and a fourth detection channel; the third detection channel includes a third transmission mirror group, a third aperture and a third detector which are sequentially arranged along the optical path direction; the fourth detection channel includes a fourth transmission mirror group, a fourth aperture and a fourth detector which are sequentially arranged along the optical path direction.

[0029] Optionally, the defect detection system also includes a collimating and shaping lens group, which is arranged between the laser light source and the wafer to be tested along the direction of the optical path, and the collimating and shaping lens group is used to correct the beam divergence angle of the laser light source and converge or collimate the light into parallel light.

[0030] Optionally, the defect detection system further includes a turntable, the wafer to be tested is arranged on the turntable, and the turntable is used to absorb the wafer to be tested and rotate.

[0031] Optionally, the wafer to be tested is a slightly rough wafer.

[0032] According to a third aspect of the present application, a storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the defect detection method described in any one of the above items is implemented.

[0033] In a fourth aspect of the present application, a computer device is provided, comprising a storage medium, a processor, and a computer program stored on the storage medium and executable on the processor, wherein the processor implements any of the above-described defect detection methods when executing the computer program.

[0034] By means of the above technical solution, the present application has at least the following beneficial effects:

[0035] The embodiments of the present application provide a defect detection method and system, a storage medium, and a computer device, wherein the defect detection method can mine the energy intensity characteristics of the scattering field of the wafer to be tested under different scattering angles, polarization characteristics, and spatial distributions by establishing a multi-channel and multi-modal wafer scattering field transmission model, and divide the channels based on this, ensuring that different channels can collect light information of different modes, so that the defect detection system can detect more types of particle defects by integrating the information of multiple channels, and achieve the purpose of covering the defect detection range from ten nanometers to micrometers, thereby increasing more defect detection types. Specifically, each channel is composed of parameters of "scattering angle range + polarization characteristics + aperture number", and is arranged and combined based on different light information modes, which greatly increases the number of channels. When the number of channels is expanded to ten or more, this advantage is more prominent, achieving full coverage detection from tiny defects of the order of ten nanometers to defects of the order of micrometers, greatly broadening the size boundary of detectable defects, and increasing many previously imperceptible defect detection types. At the same time, each channel is equipped with a relay transmission optical path to fully integrate optical information under different modes, which not only broadens the range of defects that can be detected by the defect detection system, but also ensures the reliability and practicality of the defect detection system in actual applications, and has high particle size sensitivity. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 A flowchart of a defect detection method according to an optional embodiment of the present application;

[0037] Figure 2 A flowchart of a defect detection method according to another optional embodiment of the present application;

[0038] Figure 3 A schematic diagram of the structure of a defect detection system of an optional embodiment of the present application;

[0039] Figure 4 A schematic structural diagram of a defect detection system according to another optional embodiment of the present application;

[0040] Figure 5 This is a structural schematic diagram of a defect detection system according to another optional embodiment of the present application;

[0041] Figure 6This is a structural schematic diagram of a defect detection system according to another optional embodiment of the present application;

[0042] Figure 7 This is a distribution diagram of the particle size detection range of each channel in a defect detection system designed based on a defect detection method for a certain wafer to be tested in an optional embodiment of the present application.

[0043] The reference numerals are:

[0044] 1. Laser light source; 2. Collimation and shaping lens group; 3. Turntable; 4. Wafer to be tested; 5. Objective lens; 6. Scattering angle beam splitter; 7. First beam splitter; 8. Second beam splitter; 9. First polarization beam splitter; 10. Second polarization beam splitter; 11. Third polarization beam splitter; 12. Aperture beam splitter; 13. First transmission lens group; 14. First polarization filter; 15. First aperture; 16. First detector; 17. Second transmission lens group; 18. Second Polarizing filter; 19, second aperture; 20, second detector; 21, third transmission mirror group; 22, third polarizing filter; 23, third aperture; 24, third detector; 25, fourth transmission mirror group; 26, fourth polarizing filter; 27, fourth aperture; 28, fourth detector; 29, fifth transmission mirror group; 30, fifth aperture; 31, fifth detector; 32, sixth transmission mirror group; 33, sixth aperture; 34, sixth detector. DETAILED DESCRIPTION

[0045] The present application will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other without conflict.

[0046] In this embodiment, a defect detection method is provided. Figure 1 As shown, the method includes:

[0047] Step S101: obtaining first parameter information of the incident light beam and second parameter information of the wafer 4 to be tested, wherein the first parameter information includes the wavelength, intensity and polarization direction of the incident light, and the second parameter information includes the distribution state of particles of various sizes on the surface of the wafer.

[0048] The defect detection method provided by the embodiment of the present application can be applied to the field of semiconductor manufacturing, and can be specifically applied to wafer non-image defect detection. When performing wafer non-image defect detection, first, the first parameter information of the incident light beam and the second parameter information of the wafer 4 to be tested can be obtained. For the incident light beam, the first parameter information of the incident light beam includes but is not limited to the incident light wavelength, the incident light intensity and the incident light polarization direction. In the optical path of the defect detection system, a spectrometer, an optical power meter and a polarization analyzer can be placed on the propagation path of the incident light, and the incident light wavelength, the incident light intensity and the incident light polarization direction are obtained respectively using a spectrometer, an optical power meter and a polarization analyzer. For the wafer 4 to be tested, the second parameter information of the wafer 4 to be tested includes but is not limited to the distribution state of particles of various sizes on the wafer surface. The distribution state of particles of various sizes on the wafer surface refers to the position distribution, size distribution, density distribution, aggregation degree and morphological distribution of particles on the wafer surface. In practical applications, a bright field microscope can be used to directly illuminate the wafer surface with light, so that the reflected light enters the objective lens 5 to form an image, and then the acquired microscope image is imported into professional image analysis software, such as ImageJ, etc. The image analysis software then distinguishes between particles and background by setting a grayscale threshold, and finally calculates the position, size and other information of the particles through a particle recognition algorithm.

[0049] Step S102: construct a wafer scattering field transmission model based on the first parameter information and the second parameter information. The wafer scattering field transmission model has multi-channel and multi-modal characteristics, and can obtain the scattered light intensity of particles of different sizes in each channel and each mode to determine the scattered light intensity distribution results and polarized light intensity distribution results of particles of each size.

[0050] In this embodiment, multi-channel refers to collecting heat dissipation light from different angles and in different ways. For example, some channels focus on collecting small-angle scattered light. This type of light signal is often closely related to the fine structure of tiny particles and can reflect the detailed characteristics of nanoscale defects; while some channels focus on collecting large-angle scattered light. Large-angle scattering is usually caused by large-sized particles. By analyzing these light signals, the general outline of large particle defects can be quickly located and determined. Multimodality refers to the multiple characteristic dimensions of light. Here, multimodality includes polarization mode and spatial distribution mode of light. Light in different modes has different physical manifestations. By constructing a multimodal model, the characteristics of light after interacting with wafer particles in different dimensions can be taken into account, so that the scattered light of particles of different sizes can be analyzed more carefully. In practical applications, with the help of a constructed model with multi-channel multimodal characteristics, particles of different sizes are simulated and analyzed. Because particles of different sizes will generate scattered light of different intensities in various channels and modes based on their own physical properties (such as shape, refractive index and the difference with the surrounding medium, etc.) when facing incident light, through model calculation and analysis, we can sort out how the scattered light intensity corresponding to each size of particles is distributed in each channel and mode, as well as the distribution of the polarized light intensity of the scattered light in these cases. These distribution results provide a data basis for the subsequent accurate selection of appropriate modal combinations. For example, we can know which channels and modes are more obvious and characteristic for detecting the scattered light intensity of particles in a certain size range, which is convenient for targeted detection and judgment.

[0051] Step S103: selecting a mode combination in the wafer scattered field transmission model according to the size range of the particles to be inspected and combining the scattered light intensity distribution results and the polarized light intensity distribution results of the particles of each size.

[0052] In actual wafer defect detection, the focus is often on particles in a specific size range. For example, the field of high-precision manufacturing may focus more on detecting particles in the nanometer to micrometer range, because these particles may have a significant impact on the performance of the wafer and the quality of subsequent products. Particles of different size ranges have their own rules and characteristics in terms of scattered light intensity and polarization characteristics, so it is necessary to first clarify the particle size range corresponding to the detection target, which is the starting point for selecting a suitable modal combination. Then, based on the previously determined scattered light intensity distribution and polarization light intensity distribution of particles of various sizes in different channels and different modes, the most suitable combination for detecting particles in the target size range is selected from a large number of channels and modes. For example, if it is found that the scattered light intensity of particles in a certain size range in a certain mode shows obvious peaks or characteristic changes, and the polarization light intensity also presents a state that is easy to identify and distinguish, then these channels and corresponding modes can be selected to form a modal combination. This combination can highlight the optical characteristics of the target particles to the greatest extent, improve the accuracy and effectiveness of detection, and enable the detection system to accurately capture the scattered light signals corresponding to the target particles.

[0053] Step S104: Determine the component parameters required for use in the defect detection system based on the modal combination.

[0054] In this embodiment, there are many optical elements in the defect detection system, such as lenses, apertures, polarizers, etc. Their parameters (such as the focal length of the lens, the aperture size of the aperture, the polarization direction of the polarizer, etc.) will directly affect the entire system's ability to collect and transmit light and to screen and process different modal light information. According to the selected modal combination, it means that it is determined which optical information channels with specific optical characteristics should be used to detect target particles, so it is necessary to adjust the parameters of each element in the system accordingly to match the selected modal combination, so as to ensure that the detection system can effectively collect, process and analyze those scattered light signals that can reflect the situation of the target particles in the expected manner, thereby achieving accurate defect detection. In practical applications, if the selected modal combination involves collecting light within a certain scattering angle range and with specific polarization characteristics, then it is necessary to adjust the aperture and position parameters of the diaphragm so that it can accurately filter out the light within the corresponding angle range. At the same time, it may be necessary to adjust parameters such as the angle of the polarizer to ensure that the system can accurately capture the polarization light information that meets the requirements. Ultimately, through the reasonable allocation of the parameters of each component, the entire defect detection system can operate efficiently based on the selected modal combination and accurately detect particle defects within the corresponding size range on the wafer surface.

[0055] By applying the technical solution of this embodiment, a multi-channel and multi-modal wafer scattering field transmission model is first established, which can explore the energy intensity characteristics of the scattering field of the wafer 4 to be tested under different scattering angles, polarization characteristics and spatial distributions, and then divide the channels based on this to ensure that different channels can collect light information of different modes, so that the defect detection system can detect more types of particle defects by integrating the information of multiple channels, and achieve the purpose of covering the defect detection range from ten nanometers to micrometers, thereby increasing more defect detection types. In practical applications, each channel is composed of parameters of "scattering angle range + polarization characteristics + aperture number", and is arranged and combined based on different light information modes, which greatly increases the number of channels. When the number of channels is expanded to ten or more, this advantage is more prominent, achieving full coverage detection from tiny defects of the order of ten nanometers to defects of the order of micrometers, greatly broadening the size boundary of detectable defects, and increasing many previously imperceptible defect detection types. At the same time, each channel is equipped with a relay transmission optical path to fully integrate optical information under different modes, which not only broadens the range of defects that can be detected by the defect detection system, but also ensures the reliability and practicality of the defect detection system in actual applications, and has high particle size sensitivity.

[0056] In the above embodiment, the component parameters required to be selected in the defect detection system include the scattering angle beam splitter 6 parameters, the polarization beam splitter parameters and the aperture beam splitter 12 parameters.

[0057] By selecting the parameters of the scattering angle beam splitter 6, the polarization beam splitter parameters and the aperture beam splitter 12 parameters, accurate separation and collection of optical information can be achieved. Different beam splitters can distribute optical signals to different channels according to the different characteristics of light (scattering angle, polarization state and spatial distribution), so that the detection system can obtain various modes of optical information in a targeted manner. In addition, by using a combination of different beam splitter parameters, the detection range of the defect detection system can be broadened to enable it to adapt to various types of wafers and defect situations. Whether it is a tiny defect at the nanometer level or a larger defect at the micron level, the corresponding optical signal can be obtained by setting the appropriate beam splitter parameters, thereby effectively detecting it, thereby improving the adaptability of the defect detection system under different manufacturing processes and quality requirements.

[0058] The scattering angle spectroscope 6 separates the optical signal based on the scattering angle of the light. When the light interacts with the defects on the surface of the wafer, scattered light of different angles will be generated. By adjusting the parameters of the scattering angle spectroscope 6 (such as the reflection surface angle, refractive index distribution, etc.), the optical signals of different scattering angle ranges can be guided to different channels.

[0059] Among them, the polarization beam splitter separates the optical signal according to the polarization characteristics of the light. After the light interacts with the wafer surface and defects, its polarization state will change. By adjusting the parameters of the polarization beam splitter (such as polarization direction, extinction ratio of the polarizer, etc.), optical signals with different polarization characteristics can be separated.

[0060] The aperture beam splitter 12 is mainly used to control the spatial distribution of light, and to limit or allow the passage of light by adjusting the size, shape, position and other parameters of the aperture. It can divide the light signal into different channels according to the distribution of light in space.

[0061] Further, as a refinement and extension of the specific implementation of the above embodiment, in order to fully illustrate the specific implementation process of this embodiment, another defect detection method is provided, see Figure 2 As shown, the method includes:

[0062] Step S201: obtaining first parameter information of the incident light beam and second parameter information of the wafer 4 to be tested, wherein the first parameter information includes the wavelength, intensity and polarization direction of the incident light, and the second parameter information includes the distribution state of particles of various sizes on the surface of the wafer.

[0063] Step S202: construct a wafer scattering field transmission model based on the first parameter information and the second parameter information. The wafer scattering field transmission model has multi-channel and multi-modal characteristics, and can obtain the scattered light intensity of particles of different sizes in each channel and each mode to determine the scattered light intensity distribution results and polarized light intensity distribution results of particles of each size.

[0064] Step S203: selecting a mode combination in the wafer scattered field transmission model according to the size range of the particles to be inspected and combining the scattered light intensity distribution results and the polarized light intensity distribution results of the particles of each size.

[0065] Step S204: Determine the component parameters required for use in the defect detection system based on the modal combination.

[0066] Step S205: Substitute the component parameters for the defect detection system determined according to the modal combination into the wafer scattered field transmission model to determine the particle size detection range of each channel.

[0067] Here, in the previous steps, the parameters of the components in the defect detection system have been determined according to the selected modal combination. In this step, these component parameters are substituted into the wafer scattered field transmission model in order to use this model to more accurately calculate the particle size range that each channel can detect. Because different component parameters (such as lens focal length, aperture size, etc.) will affect the propagation of light and the collection of scattered light, thereby changing the detection ability of each channel for particles of different sizes. It should be noted that the particle size detection range of each channel obtained by model calculation can provide clearer guidance for actual defect detection. For example, knowing that a certain channel is mainly used to detect small particles at the nanometer level, while another channel is more suitable for detecting larger particles at the micron level, in the actual detection process, the functions of each channel can be used more specifically to improve the accuracy and efficiency of detection. At the same time, this also helps to have a clearer understanding of the capabilities of the entire detection system and to clarify whether the particle size range it can cover meets actual needs. For example, see Figure 7 As shown, Figure 7 The particle size detection range distribution diagram of each channel in the defect detection system designed based on the defect detection method for a certain wafer 4 to be tested. Figure 7It can be clearly seen that there are obvious differences in the particle size detection range of each channel. Channel 1 has a higher signal-to-noise ratio (SNR) in the smaller particle size range, and its detection range is relatively narrow, mainly concentrated in the smaller particle size area, which shows that channel 1 has high sensitivity and accuracy for the detection of tiny particles, and is suitable for detecting nano-scale tiny particle defects that may exist on the wafer surface. The detection range of channel 2 is extended compared with channel 1. It has a certain overlap with channel 1 at the smaller particle size end, but can extend to larger particle sizes, and the SNR is also maintained at a high level in the entire range. This means that channel 2 can detect both smaller particles and slightly larger particles, and has certain compatibility and flexibility in the detection range. The curve trend of channel 5 shows that it performs well in the medium particle size area. Starting from about 70nm, the SNR gradually increases, reaching a higher value at about 200nm, and can continue to larger particle sizes, such as 400nm or even larger. This shows that channel 5 has advantages in the detection of medium-sized particles on the wafer surface and can effectively capture particle defect information within this size range. The detection range of channel 6 partially overlaps with that of channel 5, but as a whole it is more inclined to detect larger particle sizes. Its SNR can still be maintained within an acceptable range for larger particle sizes, such as from 200nm to 400nm or even larger particle sizes, which makes channel 6 one of the important channels for detecting larger particle defects on the wafer surface. The SNRs of channels 3 and 4 are relatively low and grow more slowly. Their detection ranges may focus more on other aspects or play a role under specific conditions. For example, they may provide supplementary information when detecting certain special types of defects or when used in conjunction with other channels to achieve more comprehensive defect detection. In addition, Figure 7 The upper and lower limits of the defect detection threshold are also marked. The setting of these thresholds is of great significance for judging whether there are defects on the wafer surface and the severity of the defects. When the SNR corresponding to the particle signal detected by each channel exceeds the upper limit of the defect detection threshold, it can be clearly determined that there are defects on the wafer surface and the defects are relatively serious; when the SNR is between the upper and lower limits of the threshold, further analysis and judgment may be required to determine the nature and impact of the defects; and when the SNR is lower than the lower limit of the threshold, it can be considered that there are basically no defects on the wafer surface that affect the performance within the particle size range detected by this channel. Therefore, by Figure 7 The analysis of the particle size detection range distribution diagram of each channel can provide a deep understanding of the characteristics and advantages of each channel in the defect detection system, and provide an important basis for the rational use of each channel for wafer surface defect detection. At the same time, combined with the setting of defect detection thresholds, it can more accurately evaluate the quality and performance of wafers to ensure that the wafers meet the requirements in subsequent production and applications.

[0068] Step S206: Use a standard particle calibration film to experimentally verify the detection level of each channel.

[0069] Here, the standard particle verification film is a standard sample with known particle size, distribution and other characteristics, which is used to verify the accuracy and reliability of the defect detection system. By applying the defect detection system to the detection of the standard particle verification film, the actual detection results can be compared with the known parameters of the standard particle verification film. This is equivalent to giving the defect detection system a "test" to determine whether the defect detection system can accurately detect the known particle situation, thereby evaluating the detection level of each channel. It can be understood that the detection level includes multiple aspects, such as accuracy (whether the existence and size of particles can be correctly detected), sensitivity (the ability to detect tiny particles) and repeatability (the consistency of multiple test results under the same conditions). Through this experimental verification, possible problems with the defect detection system can be found, such as the detection results of a certain channel for particles of a certain size always have large deviations, or the results of a certain channel are unstable during repeated detection.

[0070] Furthermore, step S206 includes step S2061: when the actual detection result does not match the theoretical expected result, return to the step of determining the component parameters required to be selected in the defect detection system based on the modal combination, and optimize the component parameters required to be selected in the defect detection system again.

[0071] Here, when the actual detection results do not match the theoretical expected results, it means that there is a problem with the defect detection system, and it may be that the previously determined component parameters are not completely suitable. Therefore, it is necessary to return to step S204 to optimize the component parameters required to be selected in the defect detection system again. This is a process of repeated adjustment and optimization, the purpose of which is to enable the defect detection system to better meet the requirements of actual detection. It should be noted that when optimizing component parameters, it is necessary to determine the direction of adjustment based on the difference between the actual detection results and the theoretical expected results. For example, if a channel is not sensitive enough to the detection of small particles, it may be necessary to adjust the parameters of the aperture or lens to increase the collection efficiency of the channel for scattered light from small particles; if there is a problem with the accuracy of the defect detection results, it may be necessary to reconsider the parameters of components such as polarizers to improve the screening and analysis capabilities of the polarization characteristics of scattered light. Through such an optimization process, the performance of the defect detection system is gradually improved until the actual detection results are consistent with the theoretical expected results or a satisfactory detection level is reached.

[0072] In some possible embodiments disclosed in the present application, the second parameter information also includes a distribution state of pits on the wafer surface.

[0073] In this embodiment, on the basis of considering the distribution state of particles on the wafer surface, adding the distribution state of pits on the wafer surface as a parameter can enable the defect detection system to more comprehensively evaluate the surface quality of the wafer. It should be noted that the pits on the wafer surface may produce optical phenomena such as reflection and scattering of light, which, like particle defects, will affect the performance and product quality of the wafer. Therefore, this method broadens the scope of detection, not only limited to particle defects, but also can detect pit defects. Specifically, when constructing a wafer scattering field transmission model, due to the richer second parameter information, the model can more accurately simulate the propagation and scattering of light on the wafer surface. Factors such as the shape, depth, and distribution of pits will have a unique impact on the propagation of light, and these factors are intertwined with the impact of particles. By comprehensively considering these factors, the model can more accurately calculate the scattered light intensity and polarized light intensity of particles of different positions and sizes and pits of different shapes in each channel and each mode, thereby providing more realistic data support for subsequent steps such as modal combination selection and component parameter determination.

[0074] In some possible embodiments disclosed in the present application, the second parameter information also includes a distribution state of protrusions on the wafer surface.

[0075] In this embodiment, the distribution state of the protrusions on the wafer surface is included in the second parameter information, so that the defect detection system can simultaneously consider the three types of surface defects: particles, pits and protrusions. This greatly broadens the detection range, can more comprehensively evaluate the surface quality of the wafer, and ensure that any surface irregularities that may affect the performance of the wafer can be detected. Specifically, when constructing a wafer scattered field transmission model, the presence of protrusions will significantly affect the propagation, reflection and scattering processes of light. After considering the distribution state of the protrusions, the model can more accurately simulate the complex interaction of light on the wafer surface. Protrusions of different shapes, sizes and distributions will produce different light field changes. By combining these factors, the model can more accurately calculate the optical properties of particles of different sizes, pits and protrusions themselves in each channel and each mode in the presence of protrusions. Provide a data basis that is more in line with the actual situation for subsequent detection steps.

[0076] In some possible embodiments disclosed in the present application, the second parameter information also includes a distribution state of scratches on the wafer surface.

[0077] In this embodiment, the distribution state of scratches on the wafer surface is included in the second parameter information, further improving the content of defect detection. This enables the defect detection system to comprehensively consider various types of surface defects such as particles, pits, protrusions and scratches, providing a more complete wafer surface quality assessment solution to ensure that no key factors that may affect wafer performance are missed. Specifically, the presence of scratches will affect the propagation of light. When constructing a wafer scattered field transmission model, considering the distribution state of scratches can enable the model to more accurately simulate the actual behavior of light on the wafer surface. Scratches are like tiny "light channels" that guide the propagation direction of light, change the reflection, scattering and diffraction patterns of light, and make the light field distribution more complex. By considering the scratch factor, the model can more accurately calculate the optical properties of particles of various sizes, pits, protrusions and scratches in each channel and each mode, such as scattered light intensity and polarized light intensity, thereby providing data that is more in line with the actual situation for subsequent detection steps.

[0078] In some possible embodiments disclosed in the present application, the second parameter information also includes the refractive index of the wafer 4 to be tested.

[0079] In this embodiment, the refractive index of the wafer 4 to be tested is included in the second parameter information, which can significantly improve the simulation accuracy of the wafer scattering field transmission model for the light propagation process. The refractive index is a key factor that determines the speed and direction of light propagation in the medium. Different refractive indices will cause different degrees of refraction, reflection and scattering of light inside and on the surface of the wafer. By accurately considering the refractive index, the model can more realistically restore the propagation path of light in the wafer, thereby more accurately calculating various light field characteristics, such as scattered light intensity and polarized light intensity. Specifically, in the actual wafer manufacturing process, the material and process of the wafer may cause differences in the refractive index. Considering the refractive index as a parameter can make the defect detection system better adapt to wafers with different refractive indices. This means that the defect detection method has a wider applicability, and can effectively detect surface defects under different wafer manufacturing processes and material conditions, reducing detection errors caused by changes in wafer material properties.

[0080] In some possible embodiments disclosed in the present application, the second parameter information also includes an absorption coefficient of the wafer 4 to be tested.

[0081] In this embodiment, incorporating the absorption coefficient of the wafer 4 to be tested into the second parameter information helps to construct a wafer scattering field transmission model that is closer to the actual situation. The absorption coefficient describes the ability of a material to absorb light. In a wafer, the light propagation process is not only reflected and scattered, but also absorbed. After considering the absorption coefficient, the model can more realistically simulate the energy attenuation process of light in the wafer, so that the calculation results of the light field distribution are more in line with reality. Specifically, when light propagates in a wafer, the degree of light absorption passing through defective areas and defect-free areas may be different. By accurately simulating the light absorption process, the defect detection system can better distinguish the light absorption changes caused by defects, thereby improving the detection accuracy and more accurately locating and evaluating the size, shape, distribution and other characteristics of defects.

[0082] Based on the above Figure 1 and Figure 2 The defect detection method shown in the figure, accordingly, the embodiment of the present application also provides a storage medium on which a computer program is stored, and when the computer program is executed by the processor, the above Figure 1 and Figure 2 Defect detection method shown.

[0083] Based on this understanding, the technical solution of the present application can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which can be a CD-ROM, USB flash drive, mobile hard disk, etc.), including a number of instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute the methods of various implementation scenarios of the present application.

[0084] Based on the above Figure 1 and Figure 4 The defect detection method shown in the figure, in order to achieve the above purpose, the embodiment of the present application also provides a computer device, which can be a personal computer, a server, a network device, etc., and the computer device includes a storage medium and a processor; the storage medium is used to store a computer program; the processor is used to execute the computer program to achieve the above Figure 1 and Figure 2 Defect detection method shown.

[0085] Here, the computer device may also include a user interface, a network interface, a camera, a radio frequency (RF) circuit, a sensor, an audio circuit, a WI-FI module, etc. The user interface may include a display screen (Display), an input unit such as a keyboard (Keyboard), etc., and the optional user interface may also include a USB interface, a card reader interface, etc. The network interface may optionally include a standard wired interface, a wireless interface (such as a Bluetooth interface, a WI-FI interface), etc.

[0086] Further, as Figure 1 or Figure 2 As a specific implementation of the defect detection method shown, an embodiment of the present application provides a defect detection system, which includes a plurality of detection channels, and the modal combination of each detection channel is determined according to any of the above-mentioned defect detection methods.

[0087] In a specific example, see Figure 3 As shown, the defect detection system includes a laser light source 1 and a wafer to be tested 4, the laser light source 1 is arranged toward the wafer to be tested 4, the laser light source 1 is used to emit an incident light beam, an objective lens 5 is arranged within the scattering angle range of the wafer to be tested 4, the objective lens 5 is used to collect light scattered from the surface of the wafer to be tested 4, a scattering angle beam splitter 6 is arranged on the downstream side of the objective lens 5 along the optical path direction, the scattering angle beam splitter 6 is used to split the light collected from the objective lens 5 into a first detection channel and a second detection channel, the first detection channel includes a first transmission lens group 13, a first polarization filter 14, a first aperture 15 and a first detector 16 arranged in sequence along the optical path direction, and the second detection channel includes a second transmission lens group 17, a second polarization filter 18, a second aperture 19 and a second detector 20 arranged in sequence along the optical path direction.

[0088] In this embodiment, the laser light source 1 serves as a laser illumination system of the defect detection system, which emits a light beam to illuminate the wafer surface, and the haze scattering field generated on the wafer surface and the particle scattering field generated by the wafer surface defects are received by the objective lens 5 within a scattering angle range of 0 to 80°. The 0 to 80° scattering field received by the objective lens 5 is transmitted to the first detection channel and the second detection channel. Specifically, the light collected from the objective lens 5 is split into the first detection channel and the second detection channel by the scattering angle spectroscope 6. Among them, the first detection channel is in the scattering angle range 1, and the second detection channel is in the scattering angle range 2. The scattering field in the first detection channel passes through the first transmission mirror group 13, the first polarization filter 14 and the first aperture 15 in sequence to enter the first detector 16, and the scattering field in the second detection channel passes through the second transmission mirror group 17, the second polarization filter 18 and the second aperture 19 in sequence to enter the second detector 20. Among them, the modal combination in the first detection channel is: scattering angle range 1+polarization state 1+spatial region 1, and the modal combination in the second detection channel is: scattering angle range 2+polarization state 2+spatial region 2. Here, the scattering angle range 1 and the scattering angle range 2 are combined to form a scattering field of 0 to 80 degrees received by the objective lens 5, and the scattering angle range 1 and the scattering angle range 2 are independent of each other.

[0089] In another specific example, see Figure 4As shown, the defect detection system includes a laser light source 1 and a wafer to be tested 4, the laser light source 1 is arranged toward the wafer to be tested 4, the laser light source 1 is used to emit an incident light beam, an objective lens 5 is arranged within the scattering angle range of the wafer to be tested 4, the objective lens 5 is used to collect light scattered from the surface of the wafer to be tested 4, a scattering angle beam splitter 6 is arranged on the downstream side of the objective lens 5 along the optical path direction, the scattering angle beam splitter 6 is used to split the light collected from the objective lens 5 into a first optical path and a second optical path, a first beam splitter 7 is arranged on the propagation path of the first optical path, the first beam splitter 7 is used to divide the light propagated on the first optical path into a first detection channel and a third detection channel, the first detection channel includes a first transmission mirror group 13, a first polarization mirror group 14 and a second polarization mirror group 15 which are arranged in sequence along the optical path direction. The first detection channel comprises a third transmission mirror group 21, a third polarization filter 22, a third aperture 23 and a third detector 24 which are sequentially arranged along the optical path direction; a second beam splitter 8 is arranged on the propagation path of the second optical path; the second beam splitter 8 is used for dividing the light propagating on the second optical path into a second detection channel and a fourth detection channel; the second detection channel comprises a second transmission mirror group 17, a second polarization filter 18, a second aperture 19 and a second detector 20 which are sequentially arranged along the optical path direction; the fourth detection channel comprises a fourth transmission mirror group 25, a fourth polarization filter 26, a fourth aperture 27 and a fourth detector 28 which are sequentially arranged along the optical path direction.

[0090] In this embodiment, the laser light source 1 serves as a laser illumination system of the defect detection system, which emits a light beam to illuminate the wafer surface, and the haze scattering field generated on the wafer surface and the particle scattering field generated by the wafer surface defects are received by the objective lens 5 within a scattering angle range of 0 to 80°. The 0 to 80° scattering field received by the objective lens 5 is transmitted to the first detection channel, the second detection channel, the third detection channel, and the fourth detection channel. Specifically, the light collected from the objective lens 5 is split into a first light path and a second light path by a scattering angle spectroscope 6. Among them, the first light path is in a scattering angle range 1, and the second light path is in a scattering angle range 2. The first light path in the scattering angle range 1 passes through the first spectroscope 7 and is divided into a first detection channel and a third detection channel. The scattering field in the first detection channel passes through the first transmission lens group 13, the first polarization filter 14, and the first aperture 15 in sequence to enter the first detector 16, and the scattering field in the third detection channel passes through the third transmission lens group 21, the third polarization filter 22, and the third aperture 23 in sequence to enter the third detector 24. The second light path of the scattering angle range 2 passes through the second beam splitter 8 and is divided into a second detection channel and a fourth detection channel. The scattering field in the second detection channel passes through the second transmission mirror group 17, the second polarization filter 18 and the second aperture 19 in sequence to enter the second detector 20, and the scattering field in the fourth detection channel passes through the fourth transmission mirror group 25, the fourth polarization filter 26 and the fourth aperture 27 in sequence to enter the fourth detector 28. Among them, the modal combination in the first detection channel is: scattering angle range 1 + polarization state 1 + spatial region 1, the modal combination in the third detection channel is: scattering angle range 1 + polarization state 2 + spatial region 2, the modal combination in the second detection channel is: scattering angle range 2 + polarization state 3 + spatial region 3, and the modal combination in the fourth detection channel is: scattering angle range 2 + polarization state 4 + spatial region 4.

[0091] In yet another specific example, see Figure 5As shown, the defect detection system includes a laser light source 1 and a wafer to be tested 4, the laser light source 1 is arranged toward the wafer to be tested 4, the laser light source 1 is used to emit an incident light beam, an objective lens 5 is arranged within the scattering angle range of the wafer to be tested 4, the objective lens 5 is used to collect light scattered from the surface of the wafer to be tested 4, a scattering angle beam splitter 6 is arranged on the downstream side of the objective lens 5 along the light path direction, the scattering angle beam splitter 6 is used to split the light collected from the objective lens 5 into a first light path and a second light path, a first polarization beam splitter 9 is arranged on the propagation path of the first light path, the first polarization beam splitter 9 is used to split the light propagating on the first light path into a first detection channel and a third detection channel, the first detection channel includes a first detection channel along the light path The first detection channel includes a first transmission mirror group 13, a first aperture 15 and a first detector 16 which are sequentially arranged in the direction of the optical path, the third detection channel includes a third transmission mirror group 21, a third aperture 23 and a third detector 24 which are sequentially arranged in the direction of the optical path, a second polarization beam splitter 10 is arranged on the propagation path of the second optical path, the second polarization beam splitter 10 is used to divide the light propagating on the second optical path into a second detection channel and a fourth detection channel, the second detection channel includes a second transmission mirror group 17, a second aperture 19 and a second detector 20 which are sequentially arranged in the direction of the optical path, and the fourth detection channel includes a fourth transmission mirror group 25, a fourth aperture 27 and a fourth detector 28 which are sequentially arranged in the direction of the optical path.

[0092] In this embodiment, the polarization state is usually divided into two orthogonal polarization states in the sub-mode, so the polarization beam splitter can not only separate the light energy, but also divide the polarization states of two adjacent detection channels into s-polarized light and p-polarized light according to the polarization characteristics. Figure 5 The first polarization beam splitter 9 in the example shown replaces Figure 4 The first beam splitter 7, the first polarizer and the third polarizer in the example shown, Figure 5 The second polarization beam splitter 10 in the example shown replaces Figure 4The second beam splitter 8, the second polarizer and the fourth polarizer in the example shown. Here, the laser light source 1 also serves as the laser illumination system of the defect detection system, which emits a light beam to illuminate the wafer surface, and the haze scattering field generated by the wafer surface and the particle scattering field generated by the wafer surface defects are received by the objective lens 5 within the scattering angle range of 0 to 80°. The 0-80° scattering field received by the objective lens 5 is transmitted to the first detection channel, the second detection channel, the third detection channel and the fourth detection channel. Specifically, the light collected from the objective lens 5 is split into a first light path and a second light path by the scattering angle beam splitter 6. Among them, the first light path is in the scattering angle range 1, and the second light path is in the scattering angle range 2. The first light path in the scattering angle range 1 passes through the first polarization beam splitter 9 and is divided into the first detection channel and the third detection channel. The scattering field in the first detection channel passes through the first transmission mirror group 13 and the first aperture 15 in turn to enter the first detector 16, and the scattering field in the third detection channel passes through the third transmission mirror group 21 and the third aperture 23 in turn to enter the third detector 24. The second light path of the scattering angle range 2 passes through the second polarization beam splitter 10 and is divided into a second detection channel and a fourth detection channel. The scattering field in the second detection channel passes through the second transmission mirror group 17 and the second aperture 19 in sequence to enter the second detector 20, and the scattering field in the fourth detection channel passes through the fourth transmission mirror group 25 and the fourth aperture 27 in sequence to enter the fourth detector 28. Among them, the mode combination in the first detection channel is: scattering angle range 1 + polarization state 1 + space region 1, the mode combination in the third detection channel is: scattering angle range 1 + polarization state 2 + space region 2, the mode combination in the second detection channel is: scattering angle range 2 + polarization state 3 + space region 3, and the mode combination in the fourth detection channel is: scattering angle range 2 + polarization state 4 + space region 4. Among them, polarization state 1 is orthogonal to polarization state 2, and polarization state 3 is orthogonal to polarization state 4.

[0093] In yet another specific example, see Figure 6As shown, the defect detection system includes a laser light source 1 and a wafer to be tested 4, the laser light source 1 is arranged toward the wafer to be tested 4, the laser light source 1 is used to emit an incident light beam, an objective lens 5 is arranged within the scattering angle range of the wafer to be tested 4, the objective lens 5 is used to collect light scattered from the surface of the wafer to be tested 4, a scattering angle beam splitter 6 is arranged on the downstream side of the objective lens 5 along the optical path direction, the scattering angle beam splitter 6 is used to split the light collected from the objective lens 5 into a first optical path and a second optical path, an aperture beam splitter 12 is arranged on the propagation path of the first optical path, the aperture beam splitter 12 is used to divide the light propagating on the first optical path into a third optical path and a fourth optical path, a first polarization beam splitter 9 is arranged on the propagation path of the third optical path, the first polarization beam splitter 9 is used to divide the light propagating on the third optical path into a first detection channel and a second detection channel, the first detection channel includes a first transmission lens group 13, a first aperture 15 and a first detector 16 arranged in sequence along the optical path direction, and the second ... A second transmission mirror group 17, a second aperture 19 and a second detector 20 are arranged in sequence; a third polarization beam splitter 11 is arranged on the propagation path of the fourth optical path; the third polarization beam splitter 11 is used to divide the light propagating on the fourth optical path into a fifth detection channel and a sixth detection channel; the fifth detection channel includes a fifth transmission mirror group 29, a fifth aperture 30 and a fifth detector 31 arranged in sequence along the optical path direction; the sixth detection channel includes a sixth transmission mirror group 32, a sixth aperture 33 and a sixth detector 34 arranged in sequence along the optical path direction; a second polarization beam splitter 10 is arranged on the propagation path of the second optical path; the second polarization beam splitter 10 is used to divide the light propagating on the second optical path into a third detection channel and a fourth detection channel; the third detection channel includes a third transmission mirror group 21, a third aperture 23 and a third detector 24 arranged in sequence along the optical path direction; the fourth detection channel includes a fourth transmission mirror group 25, a fourth aperture 27 and a fourth detector 28 arranged in sequence along the optical path direction.

[0094] In this embodiment, the laser light source 1, the wafer to be tested 4 and the objective lens 5 constitute a wafer scattering field generation and collection module, and the scattering field of the wafer scattering field generation and collection module is transmitted to the first detection channel, the second detection channel, the third detection channel, the fourth detection channel, the fifth detection channel and the sixth detection channel. Specifically, the light emitted by the wafer scattering field generation and collection module is split into a first light path and a second light path by a scattering angle spectroscope 6. Among them, the first light path is in the scattering angle range 1, and the second light path is in the scattering angle range 2. The first light path in the scattering angle range 1 passes through the aperture spectroscope 12 and is divided into a third light path and a fourth light path. Among them, the third light path is in the space region 1, and the fourth light path is in the space region 2. The third light path in the space region 1 passes through the first polarization spectroscope 9 again and is divided into a first detection channel and a second detection channel. The scattering field in the first detection channel passes through the first transmission mirror group 13 and the first aperture 15 in sequence to enter the first detector 16, and the scattering field in the second detection channel passes through the second transmission mirror group 17 and the second aperture 19 in sequence to enter the second detector 20. The fourth light path of the spatial region 2 passes through the third polarization beam splitter 11 and is divided into a fifth detection channel and a sixth detection channel. The scattered field in the fifth detection channel passes through the fifth transmission mirror group 29 and the fifth aperture 30 in sequence to enter the fifth detector 31, and the scattered field in the sixth detection channel passes through the sixth transmission mirror group 32 and the sixth aperture 33 in sequence to enter the sixth detector 34. The second light path in the scattering angle range 2 passes through the second polarization beam splitter 10 and is divided into a third detection channel and a fourth detection channel. The scattered field in the third detection channel passes through the third transmission mirror group 21 and the third aperture 23 in sequence to enter the third detector 24, and the scattered field in the fourth detection channel passes through the fourth transmission mirror group 25 and the fourth aperture 27 in sequence to enter the fourth detector 28. Among them, the modal combination in the first detection channel is: scattering angle range 1+polarization state 1+spatial region 1+spatial region 1-1, the modal combination in the second detection channel is: scattering angle range 1+polarization state 2+spatial region 1+spatial region 1-2, the modal combination in the third detection channel is: scattering angle range 2+polarization state 3+spatial region 3, the modal combination in the fourth detection channel is: scattering angle range 2+polarization state 4+spatial region 4, the modal combination in the fifth detection channel is: scattering angle range 1+polarization state 5+spatial region 2+spatial region 2-1, and the modal combination in the fifth detection channel is: scattering angle range 1+polarization state 6+spatial region 2+spatial region 2-2.

[0095] In a possible implementation disclosed in this application, see Figures 3 to 6 As shown, the defect detection system also includes a collimating and shaping lens group 2, which is arranged between the laser light source 1 and the wafer 4 to be tested along the optical path direction. The collimating and shaping lens group 2 is used to correct the beam divergence angle of the laser light source 1 and converge or collimate the light into parallel light.

[0096] In this embodiment, the laser light source 1 and the collimating and shaping lens group 2 together constitute the laser illumination system of the defect detection system. By setting the collimating and shaping lens group 2, the light beam divergence angle of the laser light source 1 can be corrected and the light can be converged or collimated into parallel light to reduce the divergence and loss of the light during the propagation process, so that more light can be accurately irradiated onto the wafer 4 to be tested, thereby improving the utilization rate of the light emitted by the laser light source 1 and enhancing the overall performance of the detection system.

[0097] In one possible implementation disclosed in this application, see Figures 3 to 6 As shown, the defect detection system further includes a turntable 3, on which the wafer 4 to be tested is arranged, and the turntable 3 is used for adsorbing the wafer 4 to be tested and rotating.

[0098] In this embodiment, the wafer 4 to be tested is rotated by the turntable 3, so that the laser light source 1 can illuminate and detect the wafer surface from different angles, ensuring that every area of ​​the wafer can be fully detected, avoiding missing defects due to a single detection angle, and achieving all-round, no-dead-angle detection of the wafer surface, thereby improving the coverage and completeness of defect detection.

[0099] In a possible implementation disclosed in this application, see Figures 3 to 6 As shown, the wafer 4 to be tested is a slightly rough wafer.

[0100] In this embodiment, the micro-rough wafer is closer to the surface state of the wafer in actual production. In the actual wafer manufacturing process, it is difficult to obtain a completely smooth surface, and there will always be a certain degree of micro-roughness. Using a micro-rough wafer for testing can make the test results more reflective of the quality of the actual wafer, thereby improving the practicality and reliability of the detection method in actual production.

[0101] Those skilled in the art will appreciate that the accompanying drawings are only schematic diagrams of a preferred implementation scenario, and the modules or processes in the accompanying drawings are not necessarily necessary for implementing the present application. Those skilled in the art will appreciate that the modules in the devices in the implementation scenario can be distributed in the devices of the implementation scenario according to the description of the implementation scenario, or can be changed accordingly and located in one or more devices different from the present implementation scenario. The modules of the above-mentioned implementation scenario can be combined into one module, or can be further split into multiple submodules.

[0102] The above serial numbers of this application are only for description and do not represent the advantages and disadvantages of the implementation scenarios. The above disclosure is only a few specific implementation scenarios of this application, but this application is not limited to them, and any changes that can be thought of by technicians in this field should fall within the scope of protection of this application.

Claims

1. A defect detection method, characterized in that: include: Acquire first parameter information of the incident light beam and second parameter information of the wafer to be tested, wherein the first parameter information includes the wavelength, intensity and polarization direction of the incident light, and the second parameter information includes the distribution state of particles of various sizes on the surface of the wafer; A wafer scattering field transmission model is constructed based on the first parameter information and the second parameter information. The wafer scattering field transmission model has multi-channel and multi-modal characteristics, and can obtain the scattered light intensity of particles of different sizes in each channel and each mode, so as to determine the scattered light intensity distribution results and polarized light intensity distribution results of particles of each size; Selecting a mode combination in the wafer scattered field transmission model according to the size range of the particles to be tested and combining the scattered light intensity distribution results and the polarized light intensity distribution results of the particles of each size; The component parameters required for use in the defect detection system are determined based on the modal combination.

2. The defect detection method according to claim 1, characterized in that: Also includes: The component parameters for the defect detection system determined according to the modal combination are substituted into the wafer scattered field transmission model to determine the particle size detection range of each channel.

3. The defect detection method according to claim 1, characterized in that: Also includes: The detection level of each channel was verified using a standard particle calibration film experiment.

4. The defect detection method according to claim 3, characterized in that: The use of standard particle verification sheets to verify the detection level of each channel includes: When the actual detection result does not match the theoretical expected result, return to the step of determining the component parameters required to be selected in the defect detection system based on the modal combination, and optimize the component parameters required to be selected in the defect detection system again.

5. The defect detection method according to claim 1, characterized in that: The component parameters required to be selected in the defect detection system include scattering angle beam splitter parameters, polarization beam splitter parameters and aperture beam splitter parameters.

6. The defect detection method according to claim 1, characterized in that: The second parameter information also includes the distribution state of pits on the wafer surface.

7. The defect detection method according to claim 1, characterized in that: The second parameter information also includes the distribution state of protrusions on the wafer surface.

8. A defect detection system, characterized in that: It comprises a plurality of detection channels, and the modal combination of each of the detection channels is determined according to the defect detection method according to any one of claims 1 to 7.

9. A storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the defect detection method according to any one of claims 1 to 7 is implemented.

10. A computer device comprising a storage medium, a processor, and a computer program stored in the storage medium and executable on the processor, characterized in that: When the processor executes the computer program, the defect detection method according to any one of claims 1 to 7 is implemented.

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