Linear scanning confocal microscopy system

Abstract

The invention relates to the technical field of defect detection, and particularly provides a line scanning confocal microscopy system. The line scanning confocal microscopy system comprises a light source assembly used for emitting a first line beam; the polygonal scanning galvanometer comprises a polygonal galvanometer body, and the polygonal galvanometer body is arranged on a light path of the first linear light beam and used for reflecting the first linear light beam and obtaining a second linear light beam; the polygonal scanning galvanometer is rotatably arranged around the axis of the polygonal scanning galvanometer, so that the second linear light beam scans the tested sample in the direction perpendicular to the polygonal scanning galvanometer and is reflected to form a third linear light beam; the light splitting assembly is arranged on a light path of the first linear light beam; the light splitting assembly comprises a light splitting surface which is used for reflecting the first linear light beam and transmitting the third linear light beam; and the detector assembly is arranged on a light path of the third linear light beam and is used for obtaining an image of the detected sample according to the third linear light beam. The line scanning confocal microscopy system provided by the invention can improve the accuracy and efficiency of defect detection.

Description

Technical Field

[0001] The present application relates to the technical field of defect detection, and in particular to a line scanning confocal microscopy system. Background Art

[0002] Confocal microscopy systems are often used for the detection of tiny defects, especially the detection of wafer surface defects. In confocal microscopy systems, galvanometers are usually set in the X and Y directions. By rotating the galvanometers, the light spot can scan various positions on the surface of the sample being tested in sequence. However, in fact, the speed of the galvanometer cannot change suddenly, that is, when turning, the speed deviates from the ideal set speed, which also causes the edge of the image to be exposed longer than the middle part, and the edge of the image is overexposed and needs to be cropped, which in turn affects the efficiency of detection. Summary of the invention

[0003] In view of the above analysis, the present application aims to provide a line scanning confocal microscopy system that can improve the accuracy and efficiency of defect detection.

[0004] The purpose of this application is mainly achieved through the following technical solutions:

[0005] An embodiment of the present application provides a line scanning confocal microscopy system, comprising: a light source assembly, for emitting a first line beam; a polygonal scanning galvanometer, comprising a polygonal galvanometer body, the polygonal galvanometer body being arranged in the optical path of the first line beam, for reflecting the first line beam, and obtaining a second line beam; the polygonal scanning galvanometer is rotatably arranged around its own axis, so that the second line beam scans a sample to be measured along a direction perpendicular to the polygonal scanning galvanometer, and is reflected to form a third line beam; a spectroscopic assembly, arranged in the optical path of the first line beam; the spectroscopic assembly comprises a spectroscopic surface, the spectroscopic surface is used to reflect the first line beam, and to transmit the third line beam; a detector assembly, arranged in the optical path of the third line beam, for obtaining an image of the sample to be measured according to the third line beam.

[0006] According to an embodiment of the present application, the polygonal galvanometer body is in a prism shape, and the shape of the cross section perpendicular to its own axis direction is a regular polygon; the polygonal galvanometer body includes a plurality of side wall surfaces, and the side wall surfaces are used to reflect the first line light beam.

[0007] According to the embodiment of the present application, the polygonal galvanometer body is in the shape of a regular sixteen-prism, and the rotation speed of the polygonal galvanometer body is 20,000 to 45,000 revolutions per minute.

[0008] According to an embodiment of the present application, the polygonal scanning galvanometer further includes a driving component, which drives the polygonal galvanometer body to rotate around its own axis.

[0009] According to an embodiment of the present application, the light source assembly includes: a laser, used to emit a laser beam, the laser beam is parallel light; a beam expander, arranged in the optical path of the laser beam, used to expand the laser beam; a plano-convex cylindrical lens, arranged in the optical path of the laser beam, used to converge the expanded laser beam into a first line beam, the first line beam is a line light source beam; the axis of the cylinder of the plano-convex cylindrical lens is parallel to the axis of the polygonal galvanometer body.

[0010] According to an embodiment of the present application, it also includes: a converging lens group, which is arranged in the optical path of the second line light beam, and is used to converge the second line light beam, and is used to converge the third line light beam; a reflector, which is arranged on the side of the converging lens group away from the polygonal galvanometer body along the optical path direction of the second line light beam, and is used to reflect the second line light beam so that the reflected second line light beam is directed toward the sample to be measured, and the reflector is used to reflect the third line light beam so that the reflected third line light beam is directed toward the polygonal scanning galvanometer.

[0011] According to an embodiment of the present application, the converging lens group includes: a scanning lens and a tube lens; the scanning lens is a convex lens, and along the optical path direction of the second line light beam, the scanning lens is arranged on one side of the tube lens close to the polygonal galvanometer body.

[0012] According to an embodiment of the present application, the plano-convex cylindrical lens and the scanning lens constitute a four-fold focal length optical system; the scanning lens and the tube lens constitute a four-fold focal length optical system.

[0013] According to an embodiment of the present application, the detector assembly includes: a collecting lens, which is arranged on the side of the beam splitting assembly away from the galvanometer along the optical path direction of the third line light beam, and the collecting lens is used to converge the third line light beam after transmission; a linear array detector, which is arranged on the side of the light splitting assembly away from the beam splitting assembly along the optical path direction of the third line light beam; the linear array detector is used to detect the third line light beam.

[0014] According to an embodiment of the present application, the linear array detector includes a linear array back-illuminated charge-coupled device camera, the number of longitudinal pixels of the linear array back-illuminated charge-coupled device camera is at least 8192, the minimum line time is less than or equal to 4μs, the dynamic range is greater than 66.7dB, and the maximum line speed is greater than or equal to 200kHz.

[0015] Compared with the prior art, this application has at least the following beneficial effects:

[0016] In the line-scanning confocal microscopy system of the embodiment of the present application, the light source component emits a first line beam, the first line beam is reflected by the splitting surface of the splitting component, the reflected first line beam is reflected by the polygonal galvanometer body of the polygonal scanning galvanometer to form a second line beam, the second line beam is irradiated on the surface of the sample to be tested and reflected to form a third line beam, the third line beam is reflected again by the polygonal galvanometer body, and transmits the splitting component to be detected by the detector component. The polygonal galvanometer body rotates, each side surface can reflect the first line beam, as the polygonal galvanometer body rotates, the second line beam also rotates, so as to unidirectionally scan the surface of the sample to be tested, combined with the detector component to collect the third line beam, can be spliced ​​to obtain the surface image of the sample to be tested. The line-scanning confocal microscopy system of the embodiment of the present application adopts a line light source combined with unidirectional scanning to obtain the surface image of the sample to be tested, which can improve the efficiency of defect detection. When performing multiple consecutive scans, for a certain scan process, the polygonal galvanometer body can rotate at a preset speed, so that the second line light beam scans the surface of the sample to be tested at a preset speed, so that the exposure amount of each part of the image is basically consistent, thereby improving the accuracy of detection, eliminating the process of image cropping and over-detection, and improving the efficiency of defect detection.

[0017] In the present application, the above-mentioned technical solutions can also be combined with each other to achieve more preferred combination solutions. Other features and advantages of the present application will be described in the subsequent description, and some advantages can become obvious from the description, or can be understood by practicing the present application. The purpose and other advantages of the present application can be realized and obtained through the contents particularly pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings are only for the purpose of illustrating specific embodiments and are not to be considered as limiting the present application. The same reference symbols denote the same components throughout the accompanying drawings.

[0019] Figure 1 A schematic diagram of the structure of a line scanning confocal microscope system according to an embodiment of the present application.

[0020] Figure 2 A schematic diagram of the structure of the line scanning confocal microscope system of an embodiment of the present application in a plane parallel to the plane where the sample to be measured is located.

[0021] Figure 3 A schematic diagram of the structure of the line scanning confocal microscope system of an embodiment of the present application in a plane perpendicular to the plane where the sample to be measured is located.

[0022] Reference numerals:

[0023] 1. Light source assembly; 11. Laser; 12. Beam expander; 13. Plano-convex cylindrical lens;

[0024] 2. polygonal scanning galvanometer; 21. polygonal galvanometer body; 211. side wall surface; 22. driving assembly;

[0025] 3. Spectral components;

[0026] 4. Detector assembly; 41. Light collecting lens; 42. Linear array detector;

[0027] 5. Converging lens group; 51. Scanning lens; 52. Tube lens;

[0028] 6. Reflector;

[0029] 7. Tested samples;

[0030] L1, first line beam; L2, second line beam; L3, third line beam; R, laser beam. DETAILED DESCRIPTION

[0031] The preferred embodiments of the present application are described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of the present application and are used together with the embodiments of the present application to illustrate the principles of the present application, and are not used to limit the scope of the present application.

[0032] In the description of the embodiments of the present application, it should be noted that, unless otherwise clearly specified and limited, the term "connected" should be understood in a broad sense, for example, it can be a fixed connection, or a detachable connection, or an integral connection can be a mechanical connection, or an electrical connection can be a direct connection, or it can be indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0033] The terms "top", "bottom", "above", "lower", and "on" used throughout the description are relative to the relative positions of components of a device, such as the relative positions of the top and bottom substrates within a device. It is understood that devices are multifunctional regardless of their orientation in space.

[0034] The applicant found that when using a confocal microscopy system for defect detection, the confocal microscopy system uses a point light source and sets galvanometers in the X and Y directions. By rotating the galvanometers, the point light source sequentially scans each position of the sample under test, and at the same time detects the reflected light or scattered light of the sample under test, and splices and generates an image of the surface of the sample under test, and determines whether the sample under test has defects based on the image. Considering that the light beam needs to adjust its position along the X and Y directions to scan the sample under test, the detection efficiency is low. In addition, when the galvanometer rotates and reflects the light beam, the smaller the angle between the light beam and the reflecting surface of the galvanometer per unit time, the larger the angle of rotation of the light beam, and the greater the distance swept on the surface of the sample to be tested. In other words, the speed of the light beam scanning the surface of the sample to be tested is not uniform, especially when scanning line breaks, serpentine scanning is usually used. Corresponding to the edge of the sample to be tested, the rotation angle control of the galvanometer will show the characteristics of a chord function, and it is impossible to completely achieve instantaneous switching of reverse rotation at the same speed. Therefore, it will deviate from the preset speed, resulting in a longer exposure time at the edge of the image than the middle exposure time. Therefore, the edge of the image will cause overexposure, which will affect the accuracy of defect detection. In order to obtain a complete image of the sample to be tested, it is also necessary to over-scan the area outside the sample to be tested to avoid the image of the edge of the sample to be tested being cropped, affecting the detection efficiency.

[0035] In view of the above analysis, the applicant has proposed a line scanning confocal microscopy system, including a light source component, a polygonal scanning galvanometer, a spectroscopic component and a detection component. The light source component emits a first line beam, and the first line beam is reflected by the spectroscopic surface of the spectroscopic component. The reflected first line beam is reflected by the polygonal galvanometer body of the polygonal scanning galvanometer to form a second line beam. The second line beam is irradiated on the surface of the sample to be tested and reflected to form a third line beam. The third line beam is reflected again by the polygonal galvanometer body and transmits the spectroscopic component to be detected by the detector component. The polygonal galvanometer body rotates, and each side surface can reflect the first line beam. As the polygonal galvanometer body rotates, the second line beam also rotates accordingly, thereby unidirectionally scanning the surface of the sample to be tested. Combined with the detector component to collect the third line beam, the surface image of the sample to be tested can be obtained by splicing. The line scanning confocal microscopy system of the embodiment of the present application adopts a line light source combined with unidirectional scanning to obtain the surface image of the sample to be tested, which can improve the efficiency of defect detection. When performing multiple consecutive scans, for a certain scan process, the polygonal galvanometer body can rotate at a preset speed, so that the second line light beam scans the surface of the sample to be tested at a preset speed, so that the exposure amount of each part of the image is basically consistent, thereby improving the accuracy of detection, eliminating the process of image cropping and over-detection, and improving the efficiency of defect detection.

[0036] Figure 1 A schematic diagram of the structure of a line scanning confocal microscope system according to an embodiment of the present application. Figure 2A schematic diagram of the structure of the line scanning confocal microscope system of an embodiment of the present application in a plane parallel to the plane where the sample to be measured is located. Figure 3 A schematic diagram of the structure of the line scanning confocal microscope system of an embodiment of the present application in a plane perpendicular to the plane where the sample to be measured is located.

[0037] See also Figures 1 to 3 The embodiment of the present application provides a line scanning confocal microscopy system, comprising a light source assembly 1, a polygonal scanning galvanometer 2, a spectroscopic assembly 3 and a detection assembly, wherein the light source assembly 1 emits a first line beam L1. The light source assembly 1 is used to emit the first line beam L1; the polygonal scanning galvanometer 2 comprises a polygonal galvanometer body 21, which is arranged in the optical path of the first line beam L1, and is used to reflect the first line beam L1 and obtain the second line beam L2; the polygonal scanning galvanometer 2 is rotatable around its own axis, so that the second line beam L2 scans the sample 7 to be tested along a direction perpendicular to the polygonal scanning galvanometer 2, and is reflected to form a third line beam L3; the spectroscopic assembly 3 is arranged in the optical path of the first line beam L1; the spectroscopic assembly 3 comprises a spectroscopic surface, and the spectroscopic surface is used to reflect the first line beam L1 and to transmit the third line beam L3; the detector assembly 4 is arranged in the optical path of the third line beam L3, and is used to obtain an image of the sample 7 to be tested according to the third line beam L3. Exemplarily, the first line beam L1 is perpendicular to the second line beam L2, so as to facilitate the arrangement of the positions of the various components of the line scanning confocal microscopy system of the embodiment of the present application.

[0038] The line scan confocal microscopy system of the embodiment of the present application is used for defect detection. By way of example, the sample 7 to be tested may be a device such as a wafer. In this case, the line scan confocal microscopy system of the embodiment of the present application is used to detect whether there are defects on the surface of the wafer.

[0039] The light source assembly 1 is used to emit a first line beam L1, which can be regarded as a line light source. The spectroscopic assembly 3 is used for spectrometry and has a spectroscopic surface that can reflect light and can also transmit light. The spectroscopic surface can reflect the first line beam L1, and after the first line beam L1 is reflected by the spectroscopic surface, it is directed to the polygonal scanning galvanometer 2. The polygonal galvanometer body 21 of the polygonal scanning galvanometer 2 has a plurality of side surfaces, corresponding to each side of the polygon, each side surface can reflect the first line beam L1, and the first line beam L1 will irradiate a certain side surface and reflect to form a second line beam L2. The second line beam L2 irradiates a certain position of the sample 7 to be tested, and is reflected to form a third line beam L3. The third line beam L3 will irradiate in the opposite direction and be reflected by the polygonal galvanometer body 21 again, and the reflected third line beam L3 will be directed to the spectroscopic assembly 3. The spectroscopic surface of the spectroscopic assembly 3 will transmit the third line beam L3, and the transmitted third line beam L3 will be directed to the detector assembly 4. The detector assembly 4 collects the third line beam L3 and generates an image of the sample 7 at that position. Exemplarily, the spectroscopic component 3 can use a polarization beam splitter or a dichroic mirror. If the detector component 4 detects the fluorescence emitted by the sample 7 under test, then the spectroscopic component 3 selects a dichroic mirror and adds a fluorescence filter; if the detector component 4 detects the reflected light reflected by the sample 7 under test, then the spectroscopic component 3 selects a polarization beam splitter and adds a quarter-wave plate.

[0040] It can be understood that the line scanning confocal microscopy system of the embodiment of the present application also includes a stage for carrying and fixing the sample 7 to be tested. The stage should be able to translate to adjust the position of the sample 7 to be tested. For example, the stage can adjust its position along the orthogonal direction within its own plane.

[0041] The polygonal galvanometer body 21 is rotated so that the incident angle between the first line beam L1 and the side surface of the polygonal galvanometer body 21 gradually changes, so that the second line beam L2 is also rotated, and its rotation angle is twice the rotation angle of the polygonal galvanometer body 21, so that under the premise that the first line beam L1 remains unchanged, the second line beam L2 can be swept along the tangent direction of the axis of the polygonal galvanometer body 21, thereby realizing the scanning of the surface of the sample 7 under test. Since the first line beam L1 is a linear light source, the third line beam L3 can also be regarded as a linear beam, so when the second line beam L2 is swept along a single direction, the surface of the sample 7 under test is scanned along a single direction. After the detector assembly 4 obtains the image corresponding to the third line beam L3, it can obtain the surface image of the sample 7 under test by splicing the image along the scanning direction, and use this as a basis for judging whether there are defects on the surface of the sample 7 under test.

[0042] During the detection process, when the irradiation position of the first line light beam L1 changes from the edge of a side surface to another edge at the polygonal galvanometer body 21, the corresponding second line light beam L2 can realize the first scan of the sample 7 under test; continue to rotate the polygonal galvanometer body 21, when the irradiation position of the first line light beam L1 switches from the side surface to the adjacent side surface at the polygonal galvanometer body 21, the irradiation position of the corresponding second line light beam L2 jumps from the end position of the first scan to the initial position of the second scan; continue to rotate the polygonal galvanometer body 21, when the irradiation position of the first line light beam L1 changes from the edge of the side surface adjacent to the side surface to another edge at the polygonal galvanometer body 21, the corresponding second line light beam L2 can realize the second scan of the sample 7 under test. By analogy, the line scanning confocal microscopy system of the embodiment of the present application can perform multiple continuous scans on the sample 7, and during each scan, the rotational angular velocity of the polygonal galvanometer body 21 remains unchanged, and the edge of the sample 7 corresponding to the sample 7 can be regarded as a uniform scan, eliminating image cropping and excessive detection of areas outside the sample 7, which can not only improve detection efficiency, but also improve detection accuracy. Through continuous scanning, the line scanning confocal microscopy system of the embodiment of the present application can also increase the size of the field of view, which is suitable for processing the detection of large-sized samples and dynamic samples. Illustratively, the line scanning confocal microscopy system of the embodiment of the present application can be used to observe high-resolution imaging of living cells and tissue sections in real time, especially when dynamic monitoring of rapid biological processes (such as cell division, molecular localization, etc.) is required; the line scanning confocal microscopy system of the embodiment of the present application can also be used to quickly scan surface defects, analyze material surface microstructures, etc. in high-precision manufacturing or quality control, and is particularly suitable for the fields of semiconductor and microelectronic component manufacturing; the line scanning confocal microscopy system of the embodiment of the present application can also be used for nanoscale characterization and analysis, such as surface morphology and thickness measurement of nanoparticles and thin films; the line scanning confocal microscopy system of the embodiment of the present application can also be used in environmental science to quickly scan large areas of environmental samples (such as soil, air, water samples, etc.) to analyze their microstructure or component distribution.

[0043] In addition, since the rotation mode of the polygonal galvanometer body 21 is relatively stable, the motion impact generated during acceleration and deceleration can be reduced, so that the line scanning confocal microscope system of the embodiment of the present application can have a more stable motion state and structural stability, thereby extending the service life.

[0044] Further, see Figures 1 to 3 The polygonal galvanometer body 21 is in a prism shape, and the shape of the cross section perpendicular to its own axis direction is a regular polygon; the polygonal galvanometer body 21 includes a plurality of side wall surfaces 211, and the side wall surfaces 211 are used to reflect the first line light beam L1.

[0045] The polygonal galvanometer body 21 is in the shape of a regular polygonal prism, and the corresponding axis when it rotates is the geometric axis of the prism. When using the line scanning confocal microscopy system of the embodiment of the present application for a single scan, as the polygonal galvanometer body 21 rotates, the first line light beam L1 gradually moves from the edge of a side wall surface 211 to another edge at the irradiation position of the polygonal galvanometer body 21. When using the line scanning confocal microscopy system of the embodiment of the present application for multiple consecutive scans, as the polygonal galvanometer body 21 rotates, the first line light beam L1 moves between multiple adjacent side wall surfaces 211 at the irradiation position of the polygonal galvanometer body 21, and since each side wall surface 211 is the same in shape and size, the range of each scan is the same.

[0046] Further, see Figures 1 to 3 The polygonal galvanometer body 21 is in the shape of a regular sixteen-prism, and the rotation speed of the polygonal galvanometer body 21 is 20,000 to 45,000 revolutions per minute.

[0047] When the first line beam L1 is reflected by a certain side wall surface 211, the smaller the normal angle of the first line beam L1 relative to the side wall surface 211, the uniform rotation of the second line beam L2 is converted into the scanning of the second line beam L2 on the sample 7, and the corresponding scanning process is closer to uniform speed, and then the overall exposure of the image obtained according to the third line beam L3 is more uniform, and the defect judgment of the sample 7 is more accurate. At the same time, the area that the second line beam L2 can scan on the surface of the sample 7 is smaller. The central angle corresponding to the regular sixteen prism is of appropriate size, and the angle between the two adjacent side walls 211 is 157.5°. While not making the normal angle of the first line beam L1 relative to the side wall surface 211 too large, it can also ensure that the scanning of the second line beam L2 is large enough to irradiate all positions of the sample 7. The polygonal galvanometer body 21 adopts a uniform rotation method. The faster the rotation, the faster the scanning speed and the lower the exposure. The rotation speed is 20,000 to 45,000 revolutions per minute, which ensures the detection efficiency and enables the exposure degree of each position of the detected sample 7 to be moderate, and the obtained image is clearer. For example, the area of ​​a single side wall surface 211 is 7 mm×4.5 mm.

[0048] Furthermore, the polygonal scanning galvanometer 2 also includes a driving component 22, which drives the polygonal galvanometer body 21 to rotate around its own axis. Exemplarily, the driving component 22 can be in the form of a motor to directly or indirectly drive the polygonal galvanometer body 21 to rotate. For example, the motor drives the polygonal galvanometer body 21 to rotate through a gear set.

[0049] Further, see Figures 1 to 3The light source assembly 1 includes: a laser 11, used to emit a laser beam R, and the laser beam R is parallel light; a beam expander 12, arranged in the optical path of the laser beam R, and used to expand the laser beam R; a plano-convex cylindrical lens 13, arranged in the optical path of the laser beam R, and used to converge the expanded laser beam R into a first line beam L1, and the first line beam L1 is a line light source beam; the axis of the cylinder of the plano-convex cylindrical lens 13 is parallel to the axis of the polygonal galvanometer body 21.

[0050] The laser 11 can be a semiconductor single-mode spatial light collimation laser 11, and the wavelength of the generated laser beam R can be 488nm, corresponding to a point light source, and the spot diameter is 1.2mm. In addition, the power stability of the laser 11 is required to be within 1%, and the output power of the laser 11 can be adjusted in the range of 0-20mW, and the adjustment accuracy of the output power is 0.1%.

[0051] The beam expander 12 is used to expand the laser beam R, and can expand the laser beam R by at least 5 times, so that the spot diameter of the expanded laser beam R can reach 6 mm.

[0052] A cylindrical surface is provided on one side of the plano-convex cylindrical lens 13, which can converge the expanded laser beam R along a line to form a first line beam L1. The first line beam L1 is a linear light source, and its length direction is parallel to the axis direction of the cylindrical surface of the convex cylindrical lens. Subsequently, the length directions of the second line beam L2 and the third line beam L3 are consistent with the length direction of the first line beam L1. The axis of the cylindrical surface of the plano-convex cylindrical lens 13 is parallel to the axis of the polygonal galvanometer body 21, so that the length direction of the second line beam L2 is perpendicular to its scanning direction, thereby fully utilizing the second line beam L2. Exemplarily, the focal length of the plano-convex cylindrical lens 13 can be 100 mm.

[0053] Further, see Figures 1 to 3 The line scanning confocal microscope system of the embodiment of the present application also includes: a converging lens group 5, which is arranged in the optical path of the second line beam L2, and is used to converge the second line beam L2, and is used to converge the third line beam L3; a reflector 6, which is arranged on the side of the converging lens group 5 away from the polygonal galvanometer body 21 along the optical path direction of the second line beam L2, and the reflector 6 is used to reflect the second line beam L2 so that the reflected second line beam L2 is directed toward the sample 7 to be measured, and the reflector 6 is used to reflect the third line beam L3 so that the reflected third line beam L3 is directed toward the polygonal scanning galvanometer 2.

[0054] The converging lens group 5 can converge the second line beam L2 to facilitate focusing the second beam to improve the final imaging accuracy. When the second line beam L2 is reflected by the sample 7 to form the third line beam L3, the third line beam L3 is in a divergent state, and the converging lens group 5 can make the third line beam L3 converge into parallel light again, so that the detector assembly 4 can collect imaging.

[0055] The reflector 6 can change the direction of the second line beam L2 so that the second line beam L2 can irradiate the sample 7 closer to vertically. Exemplarily, the second line beam L2 before being reflected by the reflector 6 forms a plane after scanning, which is perpendicular to the second line beam L2 after being reflected by the reflector 6, and the plane is parallel to the plane where the sample 7 is located. It can be understood that the second line beam L2 after being reflected by the reflector 6 will be directed toward the sample 7, so the objective lens can be installed on the side of the reflector 6 close to the sample 7.

[0056] Further, see Figures 1 to 3 The converging lens group 5 includes: a scanning lens 51 and a tube lens 52; the scanning lens 51 is a convex lens, and along the optical path direction of the second line light beam L2, the scanning lens 51 is arranged on one side of the tube lens 52 close to the polygonal galvanometer body 21.

[0057] In the embodiment of the present application, the area swept by the second line light beam L2 at the scanning lens 51 is relatively large, and the scanning lens 51 can converge the second light beam and appropriately reduce the area swept by the second line light beam L2 to facilitate scanning the sample 7 under test. Exemplarily, the scanning lens 51 is in the form of a convex lens with a focal length of 100 mm and a distance of 100 mm from the polygonal galvanometer body 21. The liquid crystal of the tube lens 52 can converge the second line light beam L2 so that the converged second line light beam L2 can enter the objective lens. Exemplarily, the tube lens 52 is in the form of a convex lens with a focal length of 180 mm and a distance of 280 mm from the scanning lens 51.

[0058] Further, see Figures 1 to 3 The plano-convex cylindrical lens 13 and the scanning lens 51 constitute a four-fold focal length optical system, which can filter the first line beam L1 and the second line beam L2 to reduce the influence of stray light; the scanning lens 51 and the tube lens 52 constitute a four-fold focal length optical system, which can filter the second line beam L2 and the third line beam L3 to reduce the influence of stray light. After filtering, the image obtained by the line scanning confocal microscope system of the embodiment of the present application is more accurate. The two four-fold focal length optical systems share the scanning lens 51, which can simplify the structure of the line scanning confocal microscope system of the embodiment of the present application.

[0059] Further, see Figures 1 to 3 The detector assembly 4 includes: a collecting lens 41, which is arranged on the side of the beam splitting assembly 3 away from the galvanometer along the optical path direction of the third line beam L3, and is used to converge the transmitted third line beam L3; a linear array detector 42, which is arranged on the side of the light collecting lens 41 away from the beam splitting assembly 3 along the optical path direction of the third line beam L3; the linear array detector 42 is used to detect the third line beam L3.

[0060] The light collecting lens 41 can converge the third line beam L3 after transmission, and the converged third line beam L3 is more easily received by the linear array detector 42 to obtain the image of the sample 7 under test. Exemplarily, the focal length of the light collecting lens 41 is 100 mm. The linear array detector 42 includes a linear array back-illuminated charge-coupled device camera (CCD camera), and the number of longitudinal pixels of the linear array back-illuminated charge-coupled device camera is at least 8192, the minimum line time is less than or equal to 4μs, the dynamic range is greater than 66.7dB, and the maximum line speed is greater than or equal to 200kHz. The optical signal of the third line beam L3 is received by the linear array detector 42, and the electrical signal containing the image information is obtained, and the electrical signal is transmitted to the data processing host, and the image of the sample 7 under test is generated according to the image information. Exemplarily, the data processing host can be in the form of a combination of an acquisition card and a computer. Considering that the rotation speed of the polygonal galvanometer body 21 can be 20,000 to 45,000 revolutions per minute, the frame rate of the image generated by the linear array detector 42 can exceed 200FPS, which is far higher than the frame rate of 30FPS of the point scanning system.

[0061] In summary, an embodiment of the present application provides a line-scanning confocal microscopy system. The light source component emits a first line beam, which is reflected by the splitting surface of the splitting component. The reflected first line beam is reflected by the polygonal galvanometer body of the polygonal scanning galvanometer to form a second line beam. The second line beam is irradiated on the surface of the sample to be tested and reflected to form a third line beam. The third line beam is reflected again by the polygonal galvanometer body and transmits the splitting component to be detected by the detector component. The polygonal galvanometer body rotates, and each side surface can reflect the first line beam. As the polygonal galvanometer body rotates, the second line beam also rotates accordingly, thereby unidirectionally scanning the surface of the sample to be tested. Combined with the detector component to collect the third line beam, the surface image of the sample to be tested can be obtained by splicing. The line-scanning confocal microscopy system of the embodiment of the present application adopts a line light source combined with unidirectional scanning to obtain the surface image of the sample to be tested, which can improve the efficiency of defect detection. When performing multiple consecutive scans, for a certain scan process, the polygonal galvanometer body can rotate at a preset speed, so that the second line light beam scans the surface of the sample to be tested at a preset speed, so that the exposure amount of each part of the image is basically consistent, thereby improving the accuracy of detection, eliminating the process of image cropping and over-detection, and improving the efficiency of defect detection.

[0062] The above is only a preferred specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed in the present application should be covered within the protection scope of the present application.

Claims

1. A line scanning confocal microscopy system, characterized in that: include: A light source assembly, used for emitting a first line light beam; A polygonal scanning galvanometer, comprising a polygonal galvanometer body, wherein the polygonal galvanometer body is arranged in the optical path of the first line light beam, and is used to reflect the first line light beam and obtain a second line light beam; the polygonal scanning galvanometer is rotatably arranged around its own axis, so that the second line light beam scans the sample to be tested along a direction perpendicular to the polygonal scanning galvanometer, and is reflected to form a third line light beam; a light splitting component, arranged in the optical path of the first line light beam; the light splitting component comprises a light splitting surface, the light splitting surface is used to reflect the first line light beam and to transmit the third line light beam; The detector assembly is arranged in the optical path of the third line light beam and is used for obtaining an image of the sample under test according to the third line light beam.

2. The line scanning confocal microscopy system according to claim 1, characterized in that: The polygonal galvanometer body is in a prism shape, and the shape of the cross section perpendicular to its own axis direction is a regular polygon; the polygonal galvanometer body includes a plurality of side wall surfaces, and the side wall surfaces are used to reflect the first line light beam.

3. The line scanning confocal microscopy system according to claim 2, characterized in that: The polygonal galvanometer body is in the shape of a regular sixteen-prism, and the rotation speed of the polygonal galvanometer body is 20,000 to 45,000 revolutions per minute.

4. The line scanning confocal microscopy system according to claim 1, characterized in that: The polygonal scanning galvanometer further comprises a driving component, and the driving component drives the polygonal galvanometer body to rotate around its own axis.

5. The line scanning confocal microscopy system according to claim 1, characterized in that: The light source assembly comprises: A laser, used for emitting a laser beam, wherein the laser beam is parallel light; A beam expander, disposed in the optical path of the laser beam, for expanding the laser beam; The plano-convex cylindrical lens is arranged in the optical path of the laser beam and is used to converge the expanded laser beam into the first line beam, which is a line light source beam; the axis of the cylinder of the plano-convex cylindrical lens is parallel to the axis of the polygonal galvanometer body.

6. The line scanning confocal microscopy system according to claim 5, characterized in that: Also includes: a converging lens group, arranged in the optical path of the second line light beam, for converging the second line light beam and for converging the third line light beam; A reflector is arranged on a side of the converging lens group away from the polygonal galvanometer body along the optical path direction of the second line light beam, and the reflector is used to reflect the second line light beam so that the reflected second line light beam is directed toward the sample to be measured, and the reflector is used to reflect the third line light beam so that the reflected third line light beam is directed toward the polygonal scanning galvanometer.

7. The line scanning confocal microscopy system according to claim 6, characterized in that: The converging lens group includes: a scanning lens and a tube lens; the scanning lens is a convex lens, and along the optical path direction of the second line light beam, the scanning lens is arranged on a side of the tube lens close to the polygonal galvanometer body.

8. The line scanning confocal microscopy system according to claim 7, characterized in that: The plano-convex cylindrical lens and the scanning lens form a four-fold focal length optical system; the scanning lens and the tube lens form a four-fold focal length optical system.

9. The line scanning confocal microscopy system according to claim 1, characterized in that: The detector assembly comprises: A light collecting lens, along the optical path direction of the third line light beam, the light collecting lens is arranged on a side of the light splitting component away from the galvanometer, and the light collecting lens is used to collect the third line light beam after transmission; A linear array detector is arranged on a side of the light collecting lens away from the light splitting component along the optical path direction of the third linear light beam; the linear array detector is used to detect the third linear light beam.

10. The line scanning confocal microscopy system according to claim 9, characterized in that: The linear array detector comprises a linear array back-illuminated charge coupled device camera, the number of longitudinal pixels of the linear array back-illuminated charge coupled device camera is at least 8192, the minimum line time is less than or equal to 4μs, the dynamic range is greater than 66.7dB, and the maximum line speed is greater than or equal to 200kHz.

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