Detection method and detection system

Abstract

A detection method and a detection system. When performing the first scanning detection, the detection method determines information on a first target defect on the surface of the object to be measured according to the first detection information obtained on the surface of the object to be measured; when performing the second detection scan, according to the positional relationship between the second detection light spot and the first target defect, the second detection light beam is controlled so that the power density of the second detection light spot irradiated at the position where the first target defect is located is less than the second incident power density, so as to avoid the explosion of the first target defect caused by the second detection light spot irradiating on the first target defect, thereby avoiding secondary contamination of the wafer.

Description

Technical Field

[0001] The present invention relates to the field of detection, and particularly to a detection method and a detection system. Background Art

[0002] Defect detection refers to detecting whether there are defects such as grooves, particles, scratches, etc. and the positions of the defects on a wafer. Wafer defect detection is widely applied. The existence of defects on the wafer may cause the formed devices to fail. Therefore, during the manufacturing of wafers, defect detection is usually required to ensure the product qualification rate of the wafers. In addition, during the semiconductor manufacturing process, defect detection of wafers is also required to ensure the product qualification rate.

[0003] Currently, the commonly used defect detection technology is optical detection technology. Optical detection is a method of realizing detection by the interaction between a light source and a wafer, which has the advantages of fast detection speed and no pollution. Summary of the Invention

[0004] The problem solved by the present invention is to provide a detection method and a detection system to avoid secondary contamination of the object to be detected during the detection process.

[0005] To solve the above problem, the present invention provides a detection method for detecting an object to be detected, including:

[0006] Generating a first detection light beam, the first detection light beam is incident on the surface of the object to be detected with a first incident power density to form a first detection light spot;

[0007] Performing a first scanning detection on the surface of the object to be detected through the first detection light spot to obtain first detection information on the surface of the object to be detected;

[0008] Based on the first detection information, obtaining the position information of a first target defect existing on the surface of the object to be detected; the size of the first target defect is greater than or equal to a preset size threshold;

[0009] Generating a second detection light beam, the second detection light beam is incident on the surface of the object to be detected with a second incident power density to form a second detection light spot; the second incident power density is greater than or equal to the first incident power density;

[0010] Performing a second scanning detection on the surface of the object to be detected through the second detection light spot to obtain second detection information on the surface of the object to be detected; wherein, during the process of performing the second scanning detection, according to the positional relationship between the second detection light spot and the first target defect, controlling the second detection light beam so that the power density of the second detection light spot irradiated on the position where the first target defect is located is less than the second incident power density;

[0011] Based on the first detection information and the second detection information, obtain the defect information on the surface of the object to be measured.

[0012] Correspondingly, an embodiment of the present invention further provides a detection system for detecting an object to be measured. The detection system includes:

[0013] An illumination component adapted to generate a first detection beam and a second detection beam; the first detection beam is incident on the surface of the object to be measured with a first incident power density to form a first detection spot; the second detection beam is incident on the surface of the object to be measured with a second incident power density to form a second detection spot; the second incident power density is greater than or equal to the first incident power density;

[0014] A detection component adapted to perform a first scanning detection on the surface of the object to be measured through the first detection spot to obtain the first detection information on the surface of the object to be measured; and is further adapted to perform a second scanning detection on the surface of the object to be measured through the second detection spot to obtain the second detection information on the surface of the object to be measured;

[0015] A processing component adapted to obtain the position information of the first target defect existing on the surface of the object to be measured based on the first detection information; and is further adapted to control the second detection beam according to the positional relationship between the second detection spot and the first target defect during the execution of the second scanning detection, so that the power density of the second detection spot irradiated on the position where the first target defect is located is less than the second incident power density;

[0016] A detection component adapted to obtain the defect information on the surface of the object to be measured based on the first detection information and the second detection information.

[0017] Compared with the prior art, the technical solution of the present invention has the following advantages:

[0018] The solution in the embodiment of the present invention includes: generating a first detection beam, the first detection beam is incident on the surface of the object to be measured at a first incident power density to form a first detection spot; performing a first scan detection on the surface of the object to be measured through the first detection spot to obtain first detection information on the surface of the object to be measured; based on the first detection information, obtaining the position information of a first target defect existing on the surface of the object to be measured; the size of the first target defect is greater than or equal to a preset size threshold; generating a second detection beam, the second detection beam is incident on the surface of the object to be measured at a second incident power density to form a second detection spot; the second incident power density is greater than or equal to the first incident power density; performing a second scan detection on the surface of the object to be measured through the second detection spot to obtain second detection information on the surface of the object to be measured; wherein, during the process of performing the second scan detection, according to the positional relationship between the second detection spot and the first target defect, controlling the second detection beam to reduce the power density of the second detection spot irradiated on the position where the first target defect is located; based on the first detection information and the second detection information, obtaining defect information on the surface of the object to be measured.

[0019] In the detection method in the embodiment of the present invention, when performing the first scan detection, according to the first detection information obtained on the surface of the object to be measured, information on a first target defect existing on the surface of the object to be measured is obtained, and when performing the second detection scan, the second detection beam is controlled so that the power density of the second detection spot irradiated on the position where the first target defect is located is less than the second incident power density, so as to avoid the explosion of the first target defect caused by the second detection spot irradiated on the first target defect, thereby avoiding secondary contamination of the wafer. Description of the Drawings

[0020] Figure 1 Shows a schematic flow chart of a detection method in the embodiment of the present invention;

[0021] Figure 2 Shows a schematic diagram of a detection path when performing a scan detection on the surface of the object to be measured in the embodiment of the present invention;

[0022] Figure 3 Shows a schematic diagram of a first detection image in the embodiment of the present invention;

[0023] Figure 4 Shows a schematic diagram of a positional relationship between a first detection spot and a second detection spot in the embodiment of the present invention;

[0024] Figure 5 Shows a schematic diagram of another positional relationship between a first detection spot and a second detection spot in the embodiment of the present invention;

[0025] Figure 6 The figure shows a schematic diagram of the composition structure of a detection system according to an embodiment of the present invention;

[0026] Figure 7 The figure shows a schematic diagram of the composition structure of an illumination component according to an embodiment of the present invention;

[0027] Figure 8 The figure shows a schematic diagram of the connection relationship between a shutter and a shutter controller according to an embodiment of the present invention;

[0028] Figure 9 The figure shows a schematic diagram of the connection relationship between an acousto-optic modulator and a modulator controller according to an embodiment of the present invention;

[0029] Figure 10 The figure shows a schematic diagram of the connection relationship between a carrier component and a driver according to an embodiment of the present invention. Detailed implementation manners

[0030] As can be seen from the background art, optical detection technology is a commonly used detection technology for objects to be detected.

[0031] In the field of optical detection, lasers are commonly used light sources. When performing defect detection on a wafer, the illumination light generated by the laser irradiates on the defects of the wafer, and the scattered signals generated by the defects are received by the detection component. The detection component processes the received scattered signals to obtain corresponding defect detection information.

[0032] However, when the laser irradiates on the wafer, the energy of the laser may cause some defects on the wafer to burst, such as loose large-size organic particle defects, etc., resulting in secondary contamination of the wafer.

[0033] To solve the above problems, the solution in the embodiments of the present invention includes: generating a first detection beam, the first detection beam is incident on the surface of the object to be measured at a first incident power density to form a first detection spot; performing a first scan detection on the surface of the object to be measured through the first detection spot to obtain first detection information of the surface of the object to be measured; based on the first detection information, obtaining the position information of a first target defect existing on the surface of the object to be measured; the size of the first target defect is greater than or equal to a preset size threshold; generating a second detection beam, the second detection beam is incident on the surface of the object to be measured at a second incident power density to form a second detection spot; the second incident power density is greater than or equal to the first incident power density; performing a second scan detection on the surface of the object to be measured through the second detection spot to obtain second detection information of the surface of the object to be measured; wherein, during the process of performing the second scan detection, according to the positional relationship between the second detection spot and the first target defect, controlling the second detection beam so that the power density of the second detection spot irradiated on the position where the first target defect is located is less than the second incident power density; based on the first detection information and the second detection information, obtaining the defect information of the surface of the object to be measured.

[0034] In the detection method in the embodiments of the present invention, when performing the first scan detection, according to the first detection information of the surface of the object to be measured obtained, information of a first target defect on the surface of the object to be measured is obtained, and when performing the second detection scan, the second detection beam is controlled so that the power density of the second detection spot irradiated on the position where the first target defect is located is less than the second incident power density, so as to avoid the explosion of the first target defect caused by the second detection spot irradiated on the first target defect, thereby avoiding the secondary pollution of the wafer.

[0035] Figure 1 The flowchart of a detection method in the embodiments of the present invention is shown. Please refer to Figure 1 , the detection method includes:

[0036] Step S110: Generate a first detection beam, the first detection beam is incident on the surface of the object to be measured at a first incident power density to form a first detection spot;

[0037] Step S120: Perform a first scan detection on the surface of the object to be measured through the first detection spot to obtain first detection information of the surface of the object to be measured;

[0038] Step S130: Based on the first detection information, obtain the position information of a first target defect existing on the surface of the object to be measured; the size of the first target defect is greater than or equal to a preset size threshold;

[0039] Step S140: Generate a second detection beam, and the second detection beam is incident on the surface of the object to be measured at a second incident power density to form a second detection spot; the second incident power density is greater than or equal to the first incident power density;

[0040] Step S150: Perform a second scanning detection on the surface of the object to be measured through the second detection spot to obtain second detection information on the surface of the object to be measured; wherein, during the process of performing the second scanning detection, according to the positional relationship between the second detection spot and the first target defect, control the second detection beam so that the power density of the second detection spot irradiated on the position where the first target defect is located is less than the second incident power density;

[0041] Step S160: Based on the first detection information and the second detection information, obtain defect information on the surface of the object to be measured.

[0042] To make the above objects, features, and advantages of the embodiments of the present invention more obvious and understandable, the following specifically describes the embodiments of the present invention with reference to the drawings.

[0043] Please continue to refer to Figure 1 , perform step S110 to generate a first detection beam, and the first detection beam is incident on the surface of the object to be measured at a first incident power density to form a first detection spot.

[0044] In this embodiment, the first detection beam is a single-wavelength beam. In other embodiments, the first detection beam may also be a wide-spectrum beam.

[0045] The first detection beam has a first wavelength. Among them, the first wavelength can be adjusted according to the type of illumination light emitted by the selected light source. In this embodiment, the wavelength of the first detection beam is from 100 nm to 1000 nm.

[0046] Specifically, the first detection beam includes ultraviolet light.

[0047] The first detection beam is incident on the surface of the object to be measured at a first incident power density. Among them, the first incident power density can be set according to the need for performing the first scanning detection.

[0048] The first incident power density should neither be too large nor too small. When the first incident power density is too small, the power density of the formed first detection light spot is low, and it cannot provide enough light for subsequent imaging of the surface of the object to be measured, thus unable to meet the requirements of the scanning accuracy of the first target defect on the surface of the object to be measured; when the first incident power density is too large, the power density and energy of the formed first detection light spot are relatively large, which may cause the first target defect existing on the surface of the object to be measured to explode, thereby forming secondary pollution of the object to be measured.

[0049] The first detection light beam is incident on the surface of the object to be measured at a corresponding incident angle. Wherein, the incident angle refers to the angle between the first detection light beam and the normal line of the surface of the object to be measured. Specifically, the incident angle corresponding to the first detection light beam is an acute angle or zero. When the incident angle is an acute angle, the first detection light beam is obliquely incident on the surface of the object to be measured; when the incident angle is zero, the first detection light beam is perpendicularly incident on the surface of the object to be measured.

[0050] In this embodiment, the first detection light beam is perpendicularly incident on the surface of the object to be measured. In other embodiments, the first detection light beam can also be incident on the surface of the object to be measured in an oblique incident manner.

[0051] The first detection light beam is incident on the surface of the object to be measured to form a first detection light spot. The first detection light spot forms a corresponding detection area on the surface of the object to be measured for subsequent imaging of the surface of the object to be measured.

[0052] The irradiation area of the first detection light beam on the surface of the object to be measured is the detection area formed by the first detection light spot on the surface of the object to be measured.

[0053] The shape of the first detection light spot can be set according to the needs of performing the first scanning detection.

[0054] In this embodiment, the first detection light spot is elongated. In other embodiments, the shape of the first detection light spot can also be circular or elliptical, etc.

[0055] In this embodiment, the object to be measured is a wafer. Wafers are applicable in the field of integrated circuit manufacturing and have relatively high requirements for detection accuracy. In other embodiments, the object to be measured can also be other types of objects to be measured, such as glass substrates, etc., which are not limited herein.

[0056] Please continue to refer to Figure 1 and perform step S120 to perform the first scanning detection on the surface of the object to be measured through the first detection light spot, and obtain the first detection information of the surface of the object to be measured.

[0057] Perform a first scanning detection on the surface of the object to be measured through the first detection light spot, that is, control the relative movement between the first detection light spot and the surface of the object to be measured according to a preset first detection path, so that the first detection light spot traverses all the regions to be measured on the surface of the object to be measured, thereby performing the first scanning detection on the surface of the object to be measured.

[0058] In this embodiment, the first detection light spot is strip-shaped, and the scanning direction of the first scanning detection is always perpendicular to the extension direction of the first detection light spot.

[0059] In this embodiment, the first detection path of the first scanning detection includes a plurality of concentric circles arranged radially along the surface of the object to be measured with the center of the surface of the object to be measured as the center.

[0060] Take the directions extending along the radial direction of the surface of the object to be measured and perpendicular to each other as the first direction and the second direction respectively, and take the direction passing through the center of the surface of the object to be measured and perpendicular to the extension direction of the surface of the object to be measured as the third direction.

[0061] In this embodiment, when performing the first scanning detection on the surface of the object to be measured through the first detection light spot, keep the position of the first detection light spot unchanged, rotate the object to be measured around the rotation axis along the third direction at a first rate, and move the object to be measured along the first direction or the second direction, so that the object to be measured and the first detection light spot are relatively translated from the concentric circle that has been detected in the first detection path to the adjacent next undetected concentric circle until all the concentric circles in the first detection path are traversed, so that the first detection light spot generates a relative movement with respect to the surface of the object to be measured according to the preset first detection path.

[0062] See Figure 2 , the object to be measured is circular, with the center of the surface 100 of the object to be measured as the center, the surface 100 of the object to be measured is divided into a plurality of concentric circles 1 to N arranged radially. When performing the first scanning detection, the object to be measured rotates around the rotation axis passing through the center of the surface of the object to be measured and perpendicular to the surface of the object to be measured. During the rotation of the object to be measured, in the order from the inside to the outside, the first detection light spot first scans the area within the concentric circle 1. After finishing the scanning of the concentric circle 1, translate the object to be measured along the first direction (such as parallel to the X direction) or the second direction (such as parallel to the Y direction), so that the first detection light spot generates a radial movement relative to the surface of the object to be measured to the outermost periphery of the concentric circle 2, and scan the outer area of the concentric circle 2 except the concentric circle 1... and so on, until reaching the edge of the surface 100 of the object to be measured, and complete the scanning of all the regions to be measured on the surface 100 of the object to be measured.

[0063] In other embodiments, the position of the object to be measured can also be kept unchanged, and the first detection light spot is controlled to move so that the first detection light spot moves relative to the surface of the object to be measured along a preset first detection path.

[0064] When performing the first scanning detection, the object to be measured rotates about the rotation axis at a first rate, that is, the first detection light beam scans the surface of the object to be measured at the first rate.

[0065] The first rate can be set according to the needs of the first scanning detection. In this embodiment, the first rate is 20 mm / s to 1000 mm / s.

[0066] In the field of optical detection, according to the different sources of the collected signal light, optical detection methods can be divided into bright field inspection and dark field inspection. Among them, bright field inspection is a method of detecting the surface of an object to be measured by detecting the intensity of the reflected light on the surface of the object to be measured; dark field inspection is a method of detecting the surface of the object to be measured by detecting the intensity of the scattered light on the surface of the object to be measured.

[0067] In this embodiment, the first scanning detection performed on the surface of the object to be measured by the first detection light spot is dark field detection. In other embodiments, the first scanning detection performed on the surface of the object to be measured by the first detection light spot can also be bright field detection.

[0068] Obtaining the first detection information of the surface of the object to be measured includes: during the first detection scanning process, repeatedly obtaining the first signal light formed by the scattering of the first detection light beam on the surface of the object to be measured, and forming a plurality of first detection images based on the first signal light.

[0069] When the first detection light beam irradiates the surface of the object to be measured, the surface of the object to be measured generates corresponding first signal light under the action of the first detection light spot, that is, the first detection light beam generates first signal light after passing through the object to be measured.

[0070] In this embodiment, the first scanning detection is dark field detection, and correspondingly, the first signal light is formed by the scattering of the first detection light beam on the surface of the object to be measured.

[0071] When the first detection light spot irradiates the surface of the object to be measured, the formed first signal light will change according to the type of defect or other parameters. By collecting the first signal light, the detection of the surface of the object to be measured can be realized.

[0072] Based on the first signal light, a plurality of first detection images are formed, that is, according to a preset first periodic signal, the surface of the object to be measured is optically imaged multiple times by collecting the first signal light at a preset first frequency and first time interval, and a plurality of the first detection images are formed.

[0073] The first frequency and the first time interval can be set according to the needs of the first scanning detection, and are not limited herein.

[0074] In this embodiment, by forming a plurality of the first detection images, the accuracy of the first target defect detection is improved. In other embodiments, a first detection image can also be formed to improve the speed of the first target defect detection.

[0075] In this embodiment, performing the first scanning detection is mainly used to locate the first target defect existing on the surface of the object to be measured, so that when the second scanning detection is performed subsequently, the second detection beam can be controlled to make the power density of the second detection spot irradiated at the position where the first target defect is located less than the second incident power density, thereby preventing secondary contamination of the object to be measured caused by the explosion of the first target defect.

[0076] Execute step S130 to obtain the position information of the first target defect existing on the surface of the object to be measured based on the first detection information; the size of the first target defect is greater than or equal to a preset size threshold.

[0077] Obtaining the position information of the first target defect existing on the surface of the object to be measured includes: performing a first recognition process on the plurality of first detection images to obtain the information of the first target defect existing on the surface of the object to be measured.

[0078] The smallest unit constituting an image is a pixel, as Figure 3 shown, the first detection image 300 has a plurality of pixel points 310.

[0079] When detecting the first detection image 300, the respective pixel points 310 in the first detection image 300 are correspondingly detected.

[0080] Specifically, when detecting the respective pixel points 310 in the first detection image 300, the first detection image 300 is divided into corresponding multiple unit images 315 in units of a preset size; the unit image 315 includes a plurality of adjacent pixel points; a first recognition process is performed on the first detection image 300 to obtain the unit images 315 in the first detection image 300 that meet the preset first threshold condition as the first target defect.

[0081] In this embodiment, the number of pixel points 310 included in the unit image 315 can be set according to the detection requirements of the first target defect.

[0082] As Figure 3 shown, as an example, only the unit image 315 including nine pixel points 310 is shown. Specifically, the nine pixel points 310 are arranged in a 3×3 array. It can be understood that the number of pixel points 310 included in the unit image 315 is not limited to nine.

[0083] In this embodiment, a first recognition process is performed on the first detection image 300 to obtain the unit image 315 in the first detection image 300 that meets the first threshold condition as the first target defect.

[0084] The first threshold condition serves as a judgment criterion for determining whether the unit image 315 is the first target defect. That is to say, if the first threshold condition is met, the unit image 315 is the first target defect.

[0085] As an example, the first threshold condition is used to determine whether the intensity characterization value of the unit image 315 is abnormal.

[0086] Performing the first recognition process on the multiple first detection images 300 includes: obtaining the intensity characterization value of each unit image 315 in the first detection image 300; comparing the obtained intensity characterization value with a preset first threshold to obtain the unit image 315 in the first detection image 300 whose intensity characterization value is greater than or equal to the first threshold as the first target defect.

[0087] Obtaining the intensity characterization value of the unit image 315 includes: obtaining the gray value of each pixel point 310 in the unit image 315; based on the gray values of the pixel points 310 in the unit image 315, obtaining the intensity characterization value of the unit image.

[0088] In this embodiment, the intensity characterization value of the unit image 315 is the sum of the gray values of the pixel points 310 in the unit image 315. In other embodiments, the intensity characterization value of the unit image 315 can also be obtained by performing an integration operation on the gray values of the pixel points 310 in the unit image 315.

[0089] In this embodiment, the intensity characterization value of the unit image 315 is the arithmetic mean of the intensity characterization values of the corresponding unit images 315 in the multiple first detection images 300. In this embodiment, the intensity characterization value of the unit image 315 can also be the weighted average of the intensity characterization values of the corresponding unit images 315 in the multiple first detection images 300, etc.

[0090] When a first target defect is identified from the first detection image, the position coordinates of the first target defect can be obtained.

[0091] In this embodiment, the object to be measured is a wafer, and the position coordinates of the first target defect are the position coordinates of the first target defect in the wafer coordinate system. In other embodiments, the position coordinates of the first target defect are not limited to the wafer coordinate system.

[0092] Please continue to refer to Figure 1 , perform step S140 to generate a second detection beam, and the second detection beam is incident on the surface of the object to be measured with a second incident power density to form a second detection spot; the second incident power density is greater than or equal to the first incident power density.

[0093] The second detection beam is used to be incident on the surface of the object to be measured to form a second detection spot, so as to illuminate the area to be measured on the surface of the object to be measured, thereby realizing the second scanning detection of the surface of the object to be measured.

[0094] In this embodiment, the second detection beam is a single-wavelength beam. In other embodiments, the second detection beam can also be a broadband spectral beam.

[0095] The second detection beam has a second wavelength. Among them, the second wavelength can be adjusted according to the type of illumination light emitted by the selected light source.

[0096] The second wavelength and the first wavelength may be the same or different, that is, the second detection beam and the first detection beam use light with the same or different wavelengths. In this embodiment, the second wavelength is less than the first wavelength. Specifically, the first wavelength is from 100 nm to 1000 nm, and correspondingly, the second wavelength is from 100 nm to 1000 nm.

[0097] Specifically, the second detection beam is infrared light or visible light.

[0098] The second detection beam has a second incident power density. Among them, the second incident power density can be set according to the need for subsequent second scanning detection.

[0099] In this embodiment, the second incident power density is greater than or equal to the first incident power density. Thus, when the second detection beam is incident on the surface of the object to be measured, the measurement area on the surface of the object to be measured can be illuminated more brightly, which is conducive to achieving a clearer image of the surface of the object to be measured, so as to realize a more refined and accurate detection of the surface of the object to be measured. At the same time, the fact that the second incident power density is greater than or equal to the first incident power density will result in the power density of the formed second detection spot being greater than or equal to the power density of the first detection spot. Therefore, when performing the second scanning detection on the surface of the object to be measured through the second detection spot, it is necessary to control the second detection beam so that the power density of the second detection spot irradiated at the position where the first target defect is located is less than the second incident power density, to avoid the first target defect from bursting when the second detection spot with a high power density irradiates the first target defect.

[0100] The second detection beam is incident on the surface of the object to be measured at a second incident angle.

[0101] In this embodiment, the second incident angle is the same as the first incident angle. Specifically, the first incident angle is zero, and the second incident angle is also zero, that is, both the second detection beam and the first detection beam are incident on the surface of the object to be measured in a perpendicular incident manner. In other embodiments, the second incident angle is different from the first incident angle, and the second detection beam can also be incident on the surface of the object to be measured in an oblique incident manner.

[0102] In this embodiment, the first detection beam and the first detection beam are generated by the same light source. In other embodiments, the first detection beam and the first detection beam can also be generated by different light sources.

[0103] The second detection beam is incident on the surface of the object to be measured to form a second detection spot. The second detection spot forms a corresponding detection area on the surface of the object to be measured for subsequent imaging of the surface of the object to be measured.

[0104] The irradiation area of the second detection beam on the surface of the object to be measured is the detection area formed by the second detection spot on the surface of the object to be measured.

[0105] The shape of the second detection spot can be set according to the needs of subsequent second scanning detection. In this embodiment, the surface of the object to be measured is circular, and the second detection spot is linear. In other embodiments, the shape of the second detection spot can also be circular or elliptical, etc.

[0106] Please continue to refer to Figure 1, perform step S150, perform a second scanning detection on the surface of the object to be measured through the second detection light spot, and obtain second detection information on the surface of the object to be measured; wherein, during the execution of the second scanning detection, according to the positional relationship between the second detection light spot and the first target defect, control the second detection light beam so that the power density of the second detection light spot irradiated at the position where the first target defect is located is less than the second incident power density.

[0107] Perform a second scanning detection on the surface of the object to be measured through the second detection light spot, that is, control the second detection light spot to generate relative movement relative to the surface of the object to be measured along a preset second detection path, so that the second detection light spot traverses all the regions to be measured on the surface of the object to be measured, thereby realizing the second scanning detection of the surface of the object to be measured.

[0108] In this embodiment, the second detection light spot is strip-shaped, and the scanning direction of the second scanning detection is always perpendicular to the extension direction of the second detection light spot.

[0109] In this embodiment, the second detection path of the second scanning detection includes a plurality of concentric circles centered on the center of the surface of the object to be measured and arranged along the radial direction of the surface of the object to be measured.

[0110] Take the directions extending along the radial direction of the surface of the object to be measured and perpendicular to each other as the first direction and the second direction respectively, and take the direction passing through the center of the surface of the object to be measured and perpendicular to the extension direction of the surface of the object to be measured as the third direction.

[0111] In this embodiment, when performing a second scanning detection on the surface of the object to be measured through the second detection light spot, keep the position of the second detection light spot unchanged, rotate the object to be measured around the rotation axis along the third direction at a second rate, and move the object to be measured along the first direction or the second direction, so that the object to be measured and the second detection light spot are relatively translated from the concentric circles that have been detected in the second detection path to the next adjacent undetected concentric circle until all the concentric circles in the second detection path are traversed, so that the second detection light spot generates relative movement relative to the surface of the object to be measured according to the second detection path.

[0112] For the description of the second detection path, please refer to the description of the first detection path and will not be elaborated here.

[0113] Obtaining the second detection information on the surface of the object to be measured includes: during the second detection scanning process, obtaining the second signal light formed by the surface of the object to be measured scattering the second detection light beam multiple times, and respectively forming a plurality of second detection images based on the second signal light.

[0114] When the second detection light spot irradiates the surface of the object to be measured, a corresponding second signal light is generated on the surface of the object to be measured under the action of the second detection light spot, that is, the second detection light beam generates the second signal light after passing through the object to be measured.

[0115] In this embodiment, the second scanning detection is dark field detection, and correspondingly, the second signal light is formed by scattering of the second detection light beam by the surface of the object to be measured. In other embodiments, the second scanning detection is bright field detection, and correspondingly, the second signal light is formed by reflection of the second detection light beam by the surface of the object to be measured.

[0116] When the second detection light beam irradiates the surface of the object to be measured, the generated second signal light will change according to the type of defect or other parameters. By collecting the second signal light, the detection of the surface of the object to be measured can be realized.

[0117] Based on the second signal light, a plurality of second detection images are formed, that is, according to a preset second periodic signal, the surface of the object to be measured is optically imaged multiple times by collecting the second signal light at a preset second frequency and second time interval, and a plurality of the second detection images are formed.

[0118] The second frequency and the second time interval can be set according to the needs of the first scanning detection, and are not limited here.

[0119] In this embodiment, performing the second scanning detection is mainly used to detect other defects existing on the surface of the object to be measured except the first target defect.

[0120] As described above, when performing the second scanning detection, the second detection light beam forms a second detection light spot on the surface of the object to be measured with a second incident power density. Since the second incident power density is relatively large, the energy of the formed second detection light spot is relatively high, which may cause the first target defect to explode, thereby causing secondary pollution of the object to be measured.

[0121] To avoid the above problems, during the process of performing the second scanning detection, according to the positional relationship between the second detection light spot and the first target defect, the second detection light beam is controlled so that the power density of the second detection light spot irradiating the position where the first target defect is located is less than the second incident power density, so as to avoid the explosion of the first target defect caused by the relatively large power density of the second detection light spot irradiating the first target defect, thereby avoiding secondary pollution to the object to be measured.

[0122] Obtaining the positional relationship between the second detection light spot and the first target defect includes: obtaining the irradiation area of the second detection light beam on the surface of the object to be measured; based on the irradiation area of the second detection light beam on the surface of the object to be measured and the position coordinates of the first target defect, obtaining the positional relationship between the second detection light spot and the first target defect.

[0123] In this embodiment, the irradiation area of the second detection light beam on the surface of the object to be measured is collected by the image acquisition component, so as to directly obtain the position of the second detection light spot on the surface of the object to be measured. Specifically, the second detection light spot is collected in real time through the image acquisition component, such as a camera, etc., to obtain the position of the second detection light spot on the surface of the object to be measured. Among them, the specific image acquisition component can be selected according to actual needs and is not limited here.

[0124] In this embodiment, controlling the second detection light beam so that the power density of the second detection light spot irradiated at the position where the first target defect is located is less than the second incident power density includes: shielding the second detection light beam so that the second detection light spot avoids the position where the first target defect is located.

[0125] In this embodiment, shielding the second detection light beam so that the second detection light spot avoids the position where the first target defect is located includes: when the distance between the second detection light spot and the first target defect along the scanning direction is less than a first preset distance, controlling the second detection light beam so that the power density of the second detection light spot irradiated at the position where the first target defect is located is less than the second incident power density; when the distance between the second detection light spot and the first target defect along the scanning direction is greater than or equal to a second preset distance, restoring the second detection light beam to restore the power density of the second detection light spot irradiated on the surface of the object to be measured.

[0126] Specifically, when the distance between the second detection light spot and the first target defect along the scanning direction is less than the first preset distance, the shutter is made to enter the optical path of the second detection light beam to shield the second detection light beam; when the distance between the second detection light spot and the first target defect along the scanning direction is greater than or equal to the second preset distance, the shutter is made to move out of the optical path of the second detection light beam so that the second detection light beam is incident on the surface of the object to be measured.

[0127] In this embodiment, the second detection light beam is formed by the illumination light generated by the light source, and correspondingly, the shutter disposed on the optical path of the illumination light can be used for on-off control, so as to perform shielding control on the second detection light beam.

[0128] The first preset distance and the second preset distance can be set according to actual needs, as long as the set first preset distance and second preset distance can enable the second detection light spot to avoid the first target defect in a timely and accurate manner, and there is no limitation here.

[0129] In other embodiments, controlling the second detection beam so that the power density of the second detection light spot irradiated at the position of the first target defect is less than the second incident power density can further include: reducing the output power of the light source that generates the second detection beam, so that the power density of the second detection light spot irradiated at the position of the first target defect is less than the second incident power density.

[0130] Specifically, when the distance between the second detection light spot and the first target defect along the scanning direction is less than a third preset distance, the output power of the light source that generates the second detection beam is reduced from a first power to a second power, so that the power density of the second detection light spot irradiated at the position of the first target defect is less than the second incident power density; when the distance between the second detection light spot and the first target defect along the scanning direction is greater than or equal to a fourth preset distance, the output power of the light source that generates the second detection beam is restored from the second power to the first power, so that the power density of the second detection light spot irradiated at the position of the first target defect is restored to the second incident power density.

[0131] Specifically, an acousto-optic modulator is used to control the incident power of the second detection beam generated.

[0132] In this embodiment, the second detection beam is formed by the illumination light generated by the light source, and correspondingly, an acousto-optic modulator is used to control the output power of the generated illumination light to reduce the power density of the second detection light spot irradiated at the position of the first target defect.

[0133] The first power and the second power, the third preset distance and the fourth preset distance can be set according to actual needs, as long as the set first power and second power, and the third preset distance and the fourth preset distance can enable the incident power density of the second detection beam to be reduced from the second incident power density to the third incident power density in a timely and accurate manner when irradiating the first target defect, and there is no limitation here.

[0134] As another example, controlling the second detection beam so that the power density of the second detection light spot irradiated at the position of the first target defect is less than the second incident power density can also include: controlling the relative defocus of the second detection light spot and the object to be measured to reduce the power density of the second detection light spot irradiated at the position of the first target defect.

[0135] Specifically, when it is determined that the distance in the scanning direction between the irradiation area of the second detection beam on the surface of the object to be measured and the position coordinates of the first target defect is less than a preset fifth preset distance, control the second detection spot to be defocused relative to the object to be measured; when it is determined that the distance in the scanning direction between the irradiation area of the second detection beam on the surface of the object to be measured and the position coordinates of the first target defect is greater than or equal to the sixth preset distance, control the second detection spot to be focused relative to the object to be measured.

[0136] In this embodiment, during the execution of the second detection scan, the object to be measured is placed on the carrying component and rotates around the center passing through the surface of the object to be measured and perpendicular to the rotation axis of the surface of the object to be measured along with the carrying component. Therefore, the relative defocus of the second detection spot and the object to be measured can be controlled by controlling the axial displacement of the carrying component along the rotation axis.

[0137] Specifically, when it is determined that the distance between the irradiation area of the second detection beam on the surface of the object to be measured and the position coordinates of the first target defect is less than a preset fifth preset distance, control the carrying component to drive the object to be measured to offset a preset sixth preset distance axially along the rotation axis to control the relative defocus of the second detection spot and the object to be measured; when the distance between the irradiation area of the second detection beam on the surface of the object to be measured and the position coordinates of the first target defect is greater than or equal to the seventh preset distance, control the carrying component to drive the object to be measured to return axially along the rotation axis to the preset position, so that the second detection spot is focused relative to the object to be measured.

[0138] The fifth preset distance, the sixth preset distance, and the seventh preset distance can be set according to actual needs, as long as the power density of the second detection spot irradiated to the first target defect does not cause the first target defect to explode, and no limitation is made here.

[0139] In other embodiments, it is also possible to control the second detection beam to move axially along the rotation axis so that the second detection spot is defocused relative to the object to be measured.

[0140] As described above, first, the position information of the first target defect existing on the surface of the object to be measured is obtained by performing the first scan detection. Therefore, during the execution of the second scan detection, according to the positional relationship between the second detection spot and the first target defect, the second detection beam can be controlled so that the power density of the second detection spot irradiated to the position where the first target defect is located is less than the second incident power density. Therefore, the execution order of the first scan detection and the second scan detection has a sequence.

[0141] Specifically, the second scanning detection is performed after the start of the first scanning detection, that is, the start time of the second scanning detection is later than the start time of the first scanning detection, so as to obtain the position information of the first target defect existing on the surface of the object to be measured through the first scanning detection. Thus, during the execution of the second scanning detection, the second detection beam is controlled so that the power density of the second detection spot irradiated at the position where the first target defect is located is less than the second incident power density. Furthermore, during the execution of the second scanning detection, it is possible to avoid the explosion of the first target defect caused by the high power density of the second detection spot, thereby avoiding secondary contamination of the object to be measured.

[0142] As an example, at the end of the execution of the first scanning detection, the second scanning detection is performed. In other words, the first scanning detection and the second scanning detection are carried out at different times. At this time, the first scanning detection has ended, and the position information of all the first target defects existing on the surface of the object to be measured has been obtained. After that, during the execution of the second scanning detection, the second detection beam can be controlled according to the positional relationship between the second detection spot and the first target defect so that the power density of the second detection spot irradiated at the position where the first target defect is located is less than the second incident power density.

[0143] The first scanning detection and the second scanning detection are carried out at different times, and the rate of the first scanning detection is greater than or equal to the rate of the second scanning detection, so as to quickly obtain the position information of the first target defect and improve the detection efficiency.

[0144] It should be noted that when the first scanning detection and the second scanning detection are carried out at different times, the first detection path adopted for performing the first scanning detection on the surface of the object to be measured by the first detection spot and the second detection path adopted for performing the second scanning detection on the surface of the object to be measured by the second detection spot can be the same or different, and those skilled in the art can set them according to actual needs.

[0145] As another example, the execution time of the second detection scan and the first scanning detection partially overlaps to improve the detection speed and efficiency. Specifically, after the start of the first detection scan and before the end of the first detection scan, the second scanning detection is performed along the detected path of the first scanning detection, so as to reduce the power density of the second detection spot irradiated at the position where the first target defect is located during the execution of the second scanning detection.

[0146] It can be understood that when the second detection scan partially overlaps with the execution time of the first scan detection, after the start of the first detection scan and before the end of the first detection scan, the second scan detection is performed along the detected path of the first scan detection. According to the positional relationship between the second detection spot and the first target defect, the second detection beam is controlled so that the power density of the second detection spot irradiated at the position where the first target defect is located is less than the second incident power density. Therefore, the second detection path corresponding to the second detection scan is the same as the first scan path corresponding to the first scan detection.

[0147] In addition, when the second detection scan partially overlaps with the execution time of the first scan detection, the object to be measured rotates around the rotation axis at the same rate. In other words, during the execution of the first scan detection and the second scan detection, the scan detection rate of the first detection spot is the same as that of the second detection spot.

[0148] Specifically, the object to be measured is circular, and the detection paths of the first scan detection and the second scan detection include a plurality of concentric circles centered on the center of the surface of the object to be measured and arranged along the radial direction of the surface of the object to be measured. After the start of the first scan detection, during the process of performing the second scan detection along the detected path of the first scan detection, the positions of the first detection spot and the second detection spot are relatively fixed. The first detection spot and the second detection spot are located in the same or different concentric circles, and the first detection spot and the second detection spot are adjacent.

[0149] Please refer to Figure 4 , during the process of the object to be measured rotating counterclockwise around the rotation axis passing through the center of the surface of the object to be measured and perpendicular to the surface of the object to be measured, the first detection spot 401 and the second detection spot 402 scan the surface of the object to be measured in sequence along the same detection path, in the order from concentric circle 1 to concentric circle N. Among them, on the detection path, the first detection spot 401 is located in concentric circle 2, while the second detection spot 402 is located in concentric circle 1, that is, the first detection spot 401 has completed the scan detection of concentric circle 1, and when scanning concentric circle 2, the second detection spot 402 is still in the process of scanning concentric circle 1. That is, on the same detection path, the first detection spot 401 and the second detection spot 402 are located in different concentric circles, and the first detection spot 401 is in front and the second detection spot 402 is behind.

[0150] Please refer to Figure 5 , and Figure 4In contrast, the first detection light spot 401 and the second detection light spot 402 are simultaneously located within the same concentric circle N, and within the same concentric circle N, the first detection light spot 401 is in front and the second detection light spot 402 is behind, and the surfaces of the object to be measured are respectively detected along the same detection path.

[0151] Compared with Figure 4 in Figure 5 , the time or distance by which the first detection light spot 401 leads the second detection light spot 402 is shorter, and the higher the degree of overlap between the execution times of the second detection scan and the first scan detection.

[0152] It can be understood that the higher the degree of overlap between the execution times of the second scan detection and the first scan detection, the shorter the total time spent on performing the first scan detection and the second scan detection, which is more conducive to improving the detection speed and efficiency.

[0153] In a specific implementation, when the execution times of the second scan detection and the first scan detection partially overlap, the time difference between the start time of the second scan detection and the start time of the first scan detection, or the distance difference between the second detection light spot and the first detection light spot can be set according to actual needs, as long as during the execution of the second scan detection, the power density of the second detection light spot irradiated at the position where the first target defect is located can be reduced to a level that is not sufficient to cause the first target defect to explode.

[0154] In this embodiment, when the execution times of the second scan detection and the first scan detection partially overlap, the distance between the first detection light spot and the second detection light spot is 0.1 mm to 100 mm, or the time difference between the start time of the second scan detection and the start time of the first scan detection is 100 ms to 1 s.

[0155] Please continue to refer to Figure 1 , and execute step S160 to obtain defect information on the surface of the object to be measured based on the first detection information and the second detection information.

[0156] In this embodiment, obtaining the defect information on the surface of the object to be measured based on the first detection information and the second detection information includes: performing segmentation processing on the first detection image to obtain a third detection image of the first detection image of the avoidance area; splicing the second detection image obtained by the second detection light spot with the second incident power density and the third detection image to obtain a complete image; performing second recognition processing on the complete image to obtain the defect information on the surface of the object to be measured. Among them, the second detection image obtained by using a second detection light spot with a power density smaller than the second incident power density is an avoidance image; the surface area of the object to be measured where no image is formed when the power of the second detection light spot is zero, or the surface area of the object to be measured forming the avoidance image is the avoidance area.

[0157] In this embodiment, performing segmentation processing on the first detection image includes: obtaining the position information of the avoidance area according to the position information of the first target defect in the first detection image, as well as a first preset distance and a second preset distance; obtaining a third detection image from the first detection image according to the position information of the avoidance area.

[0158] In other embodiments, it is also possible to perform segmentation processing on the second detection image, including: obtaining a third detection image by obtaining a second detection image with an image background gray value less than a preset gray value.

[0159] Performing segmentation processing on the first detection image, that is, finding the image of the avoidance area among multiple first detection images.

[0160] Specifically,

[0161] For the process of performing second recognition processing on the complete image, please refer to the corresponding description of the process of performing first recognition processing on the first detection image in step S130, which will not be elaborated here.

[0162] It can be understood that there is a preset correspondence between the size of the defect existing on the surface of the object to be measured and the recognition threshold. When the size of the defect is different, the corresponding recognition threshold will also change accordingly. In other words, when identifying the defect on the surface of the object to be measured, different sizes of defects existing on the surface of the object to be measured can be obtained based on different recognition thresholds.

[0163] Correspondingly, an embodiment of the present invention also provides a detection system.

[0164] Figure 6 The frame structure diagram of a detection system in an embodiment of the present invention is shown. Please refer to Figure 6 , the detection system includes an illumination component 10, a detection component 20, a processing component 30, and a detection component 40. Among them:

[0165] The lighting component 10 is adapted to generate a first detection beam and a second detection beam; the first detection beam is incident on the surface of the object to be measured at a first incident power density to form a first detection spot; the second detection beam is incident on the surface of the object to be measured at a second incident power density to form a second detection spot.

[0166] The detection component 20 is adapted to perform a first scanning detection on the surface of the object to be measured through the first detection spot to obtain first detection information on the surface of the object to be measured; and perform a second scanning detection on the surface of the object to be measured through the second detection spot to obtain second detection information on the surface of the object to be measured.

[0167] The processing component 30 is adapted to obtain the position information of the first target defect on the surface of the object to be measured based on the first detection information; and is further adapted to control the second detection beam during the second scanning detection to reduce the power density of the second detection spot irradiated on the position where the first target defect is located according to the positional relationship between the second detection spot and the first target defect.

[0168] The detection component 40 is adapted to obtain defect information on the surface of the object to be measured based on the first detection information and the second detection information.

[0169] In this embodiment, the lighting component 10 can generate a first detection beam and a second detection beam.

[0170] The first detection beam is used to be incident on the surface of the object to be measured to form a first detection spot, so as to perform a first scanning detection on the surface of the object to be measured through the first detection spot; the second detection beam is used to be incident on the surface of the object to be measured to form a second detection spot, so as to perform a second scanning detection on the surface of the object to be measured through the second detection spot.

[0171] In this embodiment, the first detection beam is a single-wavelength beam. In other embodiments, the first detection beam can also be a wide-spectrum beam.

[0172] The first detection beam has a first wavelength. Among them, the first wavelength can be adjusted according to the type of illumination light emitted by the selected light source. In this embodiment, the wavelength of the first detection beam is from 100 nm to 1000 nm.

[0173] Specifically, the first detection beam includes ultraviolet light.

[0174] The first detection beam has a first incident power density, and the second detection beam has a second incident power density. Among them, the first incident power density is less than the second incident power density.

[0175] The first incident power density is relatively small, so that the energy of the first detection beam is relatively low. During the first scanning detection, the first detection beam can illuminate the first target defect to locate the first target defect, and will not cause the first target defect to explode.

[0176] The second incident power density is relatively large, so that the energy of the second detection beam is relatively high. Therefore, during the second scanning detection, the second detection beam is controlled so that the power density of the second detection spot irradiated at the position where the first target defect is located is less than the second incident power density, so as to avoid causing the first target defect to explode.

[0177] The first incident power density can be set according to the needs of performing the first scanning detection, and the second incident power density can be set according to the needs of performing the second scanning detection.

[0178] In this embodiment, the first detection beam is perpendicularly incident on the surface of the object to be measured, and the second detection beam is perpendicularly incident on the surface of the object to be measured, that is, the incident angles of the first detection beam and the second detection beam are both zero. The incident angle is the angle between the beam incident on the surface of the object to be measured and the normal line of the surface of the object to be measured.

[0179] In other embodiments, the incident angle of the first detection beam is different from the incident angle of the second detection beam. For example, the incident angle of the first detection beam is zero, and the incident angle of the second detection beam is an acute angle; or, the incident angle of the second detection beam is zero, and the incident angle of the first detection beam is an acute angle; or, the incident angles of the first detection beam and the second detection beam are both acute angles, and the incident angles of the first detection beam and the second detection beam are different.

[0180] In this embodiment, both the first detection beam and the second detection beam are used to perform dark field detection on the object to be measured. In other embodiments, the first detection beam is used to perform bright field detection on the object to be measured, and the second detection beam is used to perform bright field detection on the object to be measured, or, the first detection beam is used to perform dark field detection on the object to be measured, and the second detection beam is used to perform bright field detection on the object to be measured, or, the first detection beam is used to perform bright field detection on the object to be measured, and the second detection beam is used to perform dark field detection on the object to be measured.

[0181] Figure 7 The structural schematic diagram of an illumination component in an embodiment of the present invention is shown. Refer to Figure 7, the lighting assembly includes: a light source 101 adapted to generate illumination light, the illumination light including light of a first wavelength and a second wavelength; a beam splitter 102 disposed on the optical path of the illumination light, adapted to receive the illumination light and split the illumination light to form the first detection beam and the second detection beam.

[0182] In this embodiment, the light source 101 is a laser light source.

[0183] In this embodiment, the beam splitter 102 is a grating. In other embodiments, the beam splitter can also be a dichroic mirror.

[0184] The detection assembly 20 can perform a first scan detection on the surface of the object to be measured through the first detection spot, and obtain first detection information on the surface of the object to be measured.

[0185] In other embodiments, the first detection beam and the first detection beam can also be generated by different light sources. In this embodiment, the detection assembly 20 includes: a first imaging unit adapted to, during the first detection scan process, repeatedly obtain first signal light formed by scattering of the first detection beam by the surface of the object to be measured, and form a plurality of first detection images based on the first signal light.

[0186] Correspondingly, the processing assembly 30 can obtain position information of a first target defect on the surface of the object to be measured based on the first detection information.

[0187] Specifically, the processing assembly 30 includes: a first recognition unit adapted to perform a first recognition process on the plurality of first detection images to obtain position information of a first target defect existing on the surface of the object to be measured.

[0188] In this embodiment, the detection assembly 20 can also perform a second scan detection on the surface of the object to be measured through the second detection spot, and obtain second detection information on the surface of the object to be measured.

[0189] Specifically, the detection assembly 20 further includes: a second imaging unit adapted to, during the second detection scan process, repeatedly obtain second signal light formed by scattering of the second detection beam by the surface of the object to be measured, and form a plurality of second detection images based on the second signal light respectively.

[0190] In this embodiment, the first imaging unit and the second imaging unit can be a charge-coupled device (CCD) or a complementary metal oxide semiconductor memory (CMOS) image sensor, etc.

[0191] In other embodiments, the detection component may also be provided with only one imaging unit, which is configured to detect the first signal light and the second signal light, and form a first detection image and a second detection image based on the first signal light and the second signal light respectively.

[0192] In this embodiment, the first signal light is formed by scattering of a first detection light beam by the object to be measured, and the second signal light is formed by scattering of a second detection light beam by the object to be measured. Correspondingly, both the first imaging unit and the second imaging unit perform dark field imaging on the object to be measured.

[0193] In other embodiments, the first detection signal light is formed by reflection of a first detection light beam by the object to be measured, and / or the second signal light is formed by reflection of a second detection light beam by the object to be measured, that is, one or both of the first imaging unit and the second imaging unit perform bright field imaging.

[0194] In a specific implementation, the detection component 20 may perform the second scan detection after the first scan detection is completed, or perform the second scan detection along the detected path of the first scan detection after the first scan detection starts and before the first scan detection ends.

[0195] In this embodiment, during the process of the processing component 30 performing the second scan detection, the irradiation area of the second detection light beam on the surface of the object to be measured may be acquired, and based on the position coordinates of the irradiation area and the first target defect, the positional relationship between the second detection spot and the first target defect may be acquired.

[0196] Specifically, the processing component 30 further includes: a first acquisition unit, which acquires the irradiation area of the second detection light beam on the surface of the object to be measured; and acquires the positional relationship between the second detection spot and the first target defect based on the position coordinates of the irradiation area and the first target defect; a first control unit, which is adapted to control the second detection light beam so that the power density of the second detection spot irradiated at the position where the first target defect is located is less than the second incident power density when the distance between the second detection spot and the first target defect along the scan direction is less than a first preset distance; and restore the second detection light beam to restore the power density of the second detection spot irradiated on the surface of the object to be measured when the distance between the second detection spot and the first target defect along the scan direction is greater than or equal to a second preset distance.

[0197] In this embodiment, the first acquisition unit performs real-time image acquisition on the second detection spot to acquire the irradiation area of the second detection light beam on the surface of the object to be measured.

[0198] Please refer to Figure 8 and Figure 7Different from the lighting assembly shown, the lighting assembly further includes: a shutter 103 disposed on the optical path of the illumination light and adapted to control the on / off of the illumination light so as to control the on / off of the second detection light beam. Correspondingly, the processing assembly 30 further includes: a shutter controller 301 coupled to the shutter 103 and adapted to cause the shutter 103 to enter the optical path of the illumination light before scanning the position where the first target defect is located by the second detection light spot, so that the shutter 103 enters the optical path of the second detection light beam; after the second detection light spot passes over the position where the first target defect is located, cause the shutter 103 to move out of the optical path of the illumination light, so that the shutter 103 moves out of the optical path of the second detection light beam.

[0199] Specifically, when it is determined that the distance between the second detection light spot and the first target defect along the scanning direction is less than a first preset distance, the shutter controller 301 controls the shutter 103 to open to block the illumination light so as to block the second detection light beam; when it is determined that the distance between the second detection light spot and the first target defect along the scanning direction is greater than or equal to the second preset distance, the shutter controller 301 controls the shutter 103 to return from the open state to the closed state, so that the shutter moves out of the optical path of the illumination light, thereby causing the shutter to move out of the optical path of the second detection light beam.

[0200] In other embodiments, the processing assembly 30 is further capable of controlling to reduce the incident power density of the second detection light beam according to the positional relationship between the second detection light spot and the first target defect, so as to reduce the power density of the second detection light spot irradiated at the position where the first target defect is located.

[0201] As an example, please refer to Figure 9 , different from Figure 8 that, the lighting assembly further includes: an acousto-optic modulator 104 coupled to the light source 101 and adapted to control the output power of the light source that generates the second detection light beam. Correspondingly, the processing assembly further includes: a modulator controller 302 coupled to the acousto-optic modulator 104 and adapted to control to reduce the output power of the light source that generates the second detection light beam by controlling the acousto-optic modulator 104, so that the power density of the second detection light spot irradiated at the position where the first target defect is located is less than the second incident power density.

[0202] Specifically, when it is determined that the distance between the second detection light spot and the first target defect along the scanning direction is less than a third preset distance, the acousto-optic modulator 104 is controlled by the modulator controller 302 so that the output power of the light source generating the second detection light beam drops from a first power to a second power, thereby reducing the incident power density of the second detection light beam from the second incident power density to a third incident power density; when it is determined that the distance between the second detection light spot and the first target defect along the scanning direction is greater than or equal to a fourth preset distance, the acousto-optic modulator 104 is controlled by the modulator controller 302 so that the output power of the light source generating the second detection light beam is restored from the second power to the first power, so as to restore the incident power density of the second detection light beam from the third incident power density to the second incident power density.

[0203] As another example, please refer to Figure 10 , the detection system further includes: a carrying component 50 for carrying the object under test 200. Accordingly, the processing component further includes: a driver 303, coupled to the carrying component 50, adapted to axially move the carrying component a preset distance along a rotation axis passing through the center of the surface of the object under test and perpendicular to the surface of the object under test from a preset position, so that the second detection light spot is defocused relative to the object under test, so as to reduce the light intensity of the second detection light spot irradiated at the position where the first target defect is located.

[0204] Specifically, when it is determined that the distance between the second detection light spot and the first target defect along the scanning direction is less than a preset fifth preset distance, the driver 303 controls the carrying component 50 to drive the object under test to offset a sixth preset distance along the axis of the rotation axis from the preset position, so as to control the second detection light spot to be defocused relative to the object under test; when it is determined that the distance between the second detection light spot and the first target defect along the scanning direction is greater than or equal to a preset seventh distance threshold, the driver 303 controls the carrying component 50 to drive the object under test to return to the preset position along the axis of the rotation axis, so that the second detection light spot is refocused relative to the surface of the object under test again.

[0205] The detection component 40 can obtain defect information on the surface of the object under test based on the first detection information and the second detection information.

[0206] Specifically, the detection component 40 includes: a segmentation unit, adapted to perform segmentation processing on the first detection image to obtain a third detection image of the first detection image of the avoidance area; a splicing unit, adapted to splice the second detection image and the third detection image obtained by the second detection spot with the second incident power density to obtain a complete image; a second recognition unit, adapted to perform second recognition processing on the complete image to obtain defect information on the surface of the object to be measured. Among them, the second detection image obtained by using the second detection spot with a power density less than the second incident power density is an avoidance image; the surface area of the object to be measured where no image is formed when the power of the second detection spot is zero, or the surface area of the object to be measured where the avoidance image is formed is the avoidance area.

[0207] In this embodiment, the segmentation unit can obtain the position information of the avoidance area according to the position information of the first target defect in the first detection image, as well as the first preset distance and the second preset distance; and obtain a third detection image in the first detection image according to the position information of the avoidance area. In other embodiments, the segmentation unit can also obtain a third detection image by obtaining a second detection image with an image background gray value less than a preset gray value.

[0208] The detection system can execute the detection method described in the foregoing embodiments, or can also adopt other structures to execute the detection method described in the foregoing embodiments. For the specific description of the detection system of this embodiment, reference can be made to the corresponding description of the detection method in the foregoing embodiments, which will not be elaborated here.

[0209] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be subject to the scope defined by the claims.

Claims

1. A detection method for detecting a substance to be detected, characterized in that, Including: Generating a first detection beam, which is incident on the surface of the object to be measured at a first incident power density to form a first detection spot; Performing a first scanning detection on the surface of the object to be measured through the first detection spot, and obtaining first detection information on the surface of the object to be measured; Based on the first detection information, obtaining the position information of a first target defect existing on the surface of the object to be measured; The size of the first target defect is greater than or equal to a preset size threshold; Generating a second detection beam, which is incident on the surface of the object to be measured at a second incident power density to form a second detection spot; the second incident power density is greater than or equal to the first incident power density; Performing a second scanning detection on the surface of the object to be measured through the second detection spot, and obtaining second detection information on the surface of the object to be measured; wherein, during the process of performing the second scanning detection, according to the positional relationship between the second detection spot and the first target defect, controlling the second detection beam so that the power density of the second detection spot irradiated at the position where the first target defect is located is less than the second incident power density; Based on the first detection information and the second detection information, obtaining defect information on the surface of the object to be measured.

2. The detection method according to claim 1, wherein After the start of the first scanning detection and before the end of the first scanning detection, when the second scanning detection is performed along the detected path of the first scanning detection, the distance between the second detection spot and the first detection spot is 0.1 mm to 100 mm, or the time difference between the start time of the first scanning detection and the start time of the second scanning detection is 100 ms to 1 s.

3. The detection method according to claim 1, wherein Obtaining the first detection information on the surface of the object to be measured includes: During the first scanning detection process, obtaining the first signal light scattered by the surface of the object to be measured with respect to the first detection beam multiple times, and based on the first signal light, forming multiple first detection images; obtaining the position information of the first target defect existing on the surface of the object to be measured includes: Performing a first recognition process on the multiple first detection images to obtain the position information of the first target defect existing on the surface of the object to be measured; Obtaining the second detection information on the surface of the object to be measured includes: During the second scanning detection process, obtaining the second signal light scattered by the surface of the object to be measured with respect to the second detection beam multiple times, and respectively based on the second signal light, forming multiple second detection images.

4. The detection method according to claim 1, wherein Obtaining the positional relationship between the second detection spot and the first target defect includes: Obtaining the irradiation area of the second detection beam on the surface of the object to be measured; based on the position coordinates of the irradiation area and the first target defect, obtaining the positional relationship between the second detection spot and the first target defect; According to the positional relationship between the second detection spot and the first target defect, controlling the second detection beam so that the power density of the second detection spot irradiated at the position where the first target defect is located is less than the second incident power density, includes: When the distance along the scanning direction between the second detection light spot and the first target defect is less than a first preset distance, control the second detection light beam so that the power density of the second detection light spot irradiated at the position where the first target defect is located is less than the second incident power density; when the distance along the scanning direction between the second detection light spot and the first target defect is greater than or equal to a second preset distance, restore the power density of the second detection light spot irradiated on the surface of the object to be measured.

5. The detection method according to claim 3, wherein The second detection image obtained by using the second detection light spot with a power density less than the second incident power density is an avoidance image; the surface area of the object to be measured where no image is formed when the power of the second detection light spot is zero, or the surface area of the object to be measured where the avoidance image is formed is the avoidance area; Based on the first detection information and the second detection information, obtain the defect information on the surface of the object to be measured, including: Perform segmentation processing on the first detection image, obtain the first detection image of the avoidance area to obtain a third detection image; splice the second detection image and the third detection image obtained by the second detection light spot with the second incident power density to obtain a complete image; perform a second recognition process on the complete image to obtain the defect information on the surface of the object to be measured.

6. The detection method according to claim 5, characterized in that, The segmentation processing of the first detection image includes: According to the position information of the first target defect in the first detection image, as well as the first preset distance and the second preset distance, obtain the position information of the avoidance area; obtain the third detection image in the first detection image according to the position information of the avoidance area; or, The segmentation processing of the second detection image includes: obtaining the second detection image with the background gray value of the image less than the preset gray value to obtain the third detection image.

7. The detection method according to claim 1, characterized in that, Controlling the second detection light beam so that the power density of the second detection light spot irradiated at the position where the first target defect is located is less than the second incident power density includes: By shielding the second detection light beam, the second detection light spot is made to avoid the position where the first target defect is located; Making the second detection light spot avoid the position where the first target defect is located by shielding the second detection light beam includes: before the second detection light spot scans the position where the first target defect is located, making the shutter enter the optical path of the second detection light beam; after the second detection light spot passes over the position where the first target defect is located, making the shutter move out of the optical path of the second detection light beam.

8. The detection method according to claim 1, wherein Controlling the second detection light beam so that the power density of the second detection light spot irradiated at the position where the first target defect is located is less than the second incident power density includes: By reducing the output power of the light source generating the second detection light beam, the power density of the second detection light spot irradiated at the position where the first target defect is located is made less than the second incident power density; or, By controlling the relative defocus of the second detection light spot and the object to be measured, the power density of the second detection light spot irradiated at the position where the first target defect is located is made less than the second incident power density.

9. The detection method according to claim 1, wherein The object to be measured is circular; the first detection light spot is strip-shaped, the second detection light spot is strip-shaped, the scanning direction of the first scanning detection is always perpendicular to the extension direction of the first detection light spot, and the scanning direction of the second scanning detection is always perpendicular to the extension direction of the second detection light spot; Taking the directions extending along the radial direction of the surface of the object to be measured and perpendicular to each other as the first direction and the second direction respectively, and taking the direction passing through the center of the circle of the surface of the object to be measured and perpendicular to the extension direction of the surface of the object to be measured as the third direction; The detection paths of the first scanning detection and the second scanning detection include a plurality of concentric circles arranged along the radial direction of the surface of the object to be measured with the center of the circle of the surface of the object to be measured as the center; Performing the first scanning detection on the surface of the object to be measured by the first detection light spot includes: relatively rotating the object to be measured and the first detection light spot around the rotation axis along the third direction at a first rate, and relatively moving the object to be measured and the first detection light spot along the first direction or the second direction, so that the object to be measured and the first detection light spot are relatively translated from the concentric circle that has been detected in the detection path to the adjacent next undetected concentric circle until all the concentric circles in the detection path are traversed, so as to perform the first scanning detection on the surface of the object to be measured; Performing the second scanning detection on the surface of the object to be measured includes: relatively rotating the object to be measured and the first detection light spot around the rotation axis along the third direction at a second rate, and relatively moving the object to be measured and the second detection light spot along the first direction or the second direction, so that the object to be measured and the first detection light spot are relatively translated from the concentric circle that has been detected in the detection path to the adjacent next undetected concentric circle until all the concentric circles in the detection path are traversed, so as to perform the second scanning detection on the surface of the object to be measured.

10. The detection method according to claim 1, wherein After the first scanning detection is completed, the second scanning detection is performed; the rate of the first scanning detection is greater than the rate of the second scanning detection.

11. The detection method according to claim 1, characterized in that, The object to be measured is circular, and the detection paths of the first scanning detection and the second scanning detection include a plurality of concentric circles arranged along the radial direction of the surface of the object to be measured with the center of the circle of the surface of the object to be measured as the center; During the process of performing the second scanning detection along the detected path of the first scanning detection after the start of the first scanning detection, the positions of the first detection light spot and the second detection light spot are relatively fixed, the first detection light spot and the second detection light spot are located in the same or different concentric circles, and the first detection light spot and the second detection light spot are adjacent.

12. The detection method according to claim 1, wherein The first detection light beam includes light of a first wavelength; the second detection light beam includes light of a second wavelength, the first wavelength and the second wavelength are different, the first wavelength is an ultraviolet wavelength, and the second wavelength is a visible light wavelength or an infrared light wavelength; Generating the first detection light beam and the second detection light beam includes: generating illumination light through a light source, and the illumination light includes light of the first wavelength and the second wavelength; Receiving the illumination light through a beam splitter, and splitting the illumination light to form the first detection beam and the second detection beam; the beam splitter is a grating or a dichroic mirror.

13. A detection system for detecting a substance to be detected, characterized in that, Comprising: An illumination assembly adapted to generate a first detection beam and a second detection beam; the first detection beam is incident on the surface of the object to be measured at a first incident power density to form a first detection spot; the second detection beam is incident on the surface of the object to be measured at a second incident power density to form a second detection spot; the second incident power density is greater than or equal to the first incident power density; A detection assembly adapted to perform a first scan detection on the surface of the object to be measured through the first detection spot to obtain first detection information on the surface of the object to be measured; and further adapted to perform a second scan detection on the surface of the object to be measured through the second detection spot to obtain second detection information on the surface of the object to be measured; A processing assembly adapted to obtain position information of a first target defect existing on the surface of the object to be measured based on the first detection information; Further adapted to control the second detection beam during the second scan detection process such that the power density of the second detection spot irradiated on the position where the first target defect is located is less than the second incident power density according to the positional relationship between the second detection spot and the first target defect; A detection component adapted to obtain defect information on the surface of the object to be measured based on the first detection information and the second detection information.

14. The detection system according to claim 13, characterized in that, The processing assembly further includes: A first acquisition unit that acquires the irradiation area of the second detection beam on the surface of the object to be measured; and based on the position coordinates of the irradiation area and the first target defect, acquires the positional relationship between the second detection spot and the first target defect; A first control unit adapted to control the second detection beam such that the power density of the second detection spot irradiated on the position where the first target defect is located is less than the second incident power density when it is determined that the distance between the second detection spot and the first target defect along the scan direction is less than a first preset distance; and restore the power density of the second detection spot irradiated on the surface of the object to be measured when the distance between the second detection spot and the first target defect along the scan direction is greater than or equal to a second preset distance.

15. The detection system according to claim 13, wherein The detection assembly includes: a first imaging unit adapted to acquire the first signal light scattered by the surface of the object to be measured with respect to the first detection beam multiple times during the first scan detection process, and form a plurality of first detection images based on the first signal light; The processing assembly includes: a first recognition unit adapted to perform a first recognition process on the plurality of first detection images to obtain position information of a first target defect existing on the surface of the object to be measured; The detection assembly further includes: a second imaging unit adapted to acquire the second signal light scattered by the surface of the object to be measured with respect to the second detection beam multiple times during the second scan detection process, and form a plurality of second detection images based on the second signal light respectively.

16. The detection system according to claim 15, wherein The second detection image obtained by using a second detection light spot with a power density less than the second incident power density is an avoidance image; the surface area of the object to be measured where no image is formed when the power of the second detection light spot is zero, or the surface area of the object to be measured where the avoidance image is formed is the avoidance area; The detection component includes: a segmentation unit, adapted to perform segmentation processing on the first detection image to obtain a third detection image of the first detection image of the avoidance area; a splicing unit, adapted to splice the second detection image and the third detection image obtained by the second detection light spot with the second incident power density to obtain a complete image; a second recognition unit, adapted to perform second recognition processing on the complete image to obtain defect information on the surface of the object to be measured; The segmentation unit is adapted to obtain the position information of the avoidance area according to the position information of the first target defect in the first detection image, as well as a first preset distance and a second preset distance; obtain a third detection image in the first detection image according to the position information of the avoidance area; or obtain a third detection image by obtaining a second detection image with an image background gray value less than a preset gray value.

17. The detection system according to claim 13, characterized in that, The first detection light beam includes light with a first wavelength; the second detection light beam includes light with a second wavelength, the first wavelength and the second wavelength are different, the first wavelength is an ultraviolet wavelength, and the second wavelength is a visible light wavelength or an infrared wavelength; The illumination component includes: a light source, adapted to generate illumination light, and the illumination light includes light with a first wavelength and a second wavelength; A beam splitter is disposed on the optical path of the illumination light, adapted to receive the illumination light and split the illumination light to form the first detection light beam and the second detection light beam; the beam splitter is a grating or a dichroic mirror.

18. The detection system according to claim 17, characterized in that, The illumination component further includes: a shutter, disposed on the optical path of the illumination light, adapted to control the on / off of the second detection light beam by controlling the on / off of the illumination light; The processing component includes: a shutter controller, coupled to the shutter, adapted to make the shutter enter the optical path of the illumination light before scanning the position where the first target defect is located by the second detection light spot, so that the shutter enters the optical path of the second detection light beam; after the second detection light spot passes over the position where the first target defect is located, make the shutter move out of the optical path of the illumination light, so that the shutter moves out of the optical path of the second detection light beam.

19. The detection system according to claim 17, characterized in that, The illumination component further includes: an acousto-optic modulator, coupled to the light source, adapted to control the output power of the light source that generates the second detection light beam; The processing component includes: a modulator controller, coupled to the acousto-optic modulator, adapted to control the acousto-optic modulator to reduce the output power of the light source that generates the second detection light beam, so that the power density of the second detection light spot irradiated on the position where the first target defect is located is less than the second incident power density; or, The detection system further includes: a carrying component, adapted to carry the object to be measured; The processing component includes: a driver, which is adapted to control the carrier component to axially move a preset distance along a rotation axis passing through the center of the surface of the object to be measured and perpendicular to the surface of the object to be measured, so that the second detection light spot is defocused relative to the object to be measured, and the power density of the second detection light spot irradiated at the position where the first target defect is located is less than the second incident power density.

20. The detection system according to claim 17, wherein The object to be measured is circular, and the detection paths for the detection component to perform the first scan detection and the second scan detection include a plurality of concentric circles arranged along the radial direction of the surface of the object to be measured with the center of the surface of the object to be measured as the center; When the detection component performs the second scan detection along the detected path of the first scan detection after the start and before the end of the first scan detection, on the detection path, the positions of the first detection light spot and the second detection light spot generated by the illumination component are relatively fixed, the first detection light spot and the second detection light spot are located in the same or different concentric circles, and the first detection light spot and the second detection light spot are adjacent.

Images