Twin defect detection device

Abstract

The utility model provides a kind of twin crystal defect detection device, comprising: conveyor belt, the conveyor belt is used to convey the silicon wafer to be detected along first direction;At least two light source components, each light source component is arranged at the outer periphery of detection station and is located above the conveyor belt, the projection length of the straight line distance L between the center of the light emitting surface of each light source component and the center of the silicon wafer to be detected located at the detection station on horizontal plane is 380-600mm, the projection length of the straight line distance L on vertical plane is 500-800mm;The extension direction of the light source component is obliquely arranged relative to the conveying direction of the silicon wafer to be detected, and the light emitting surface of the light source component is obliquely arranged relative to the plane where the silicon wafer to be detected is located;Camera is used to collect the image information of the silicon wafer to be detected.The utility model solves the technical problem that single direction lighting in the prior art makes it difficult to effectively detect twin crystal defects under high-speed motion state, resulting in the inability to detect twin crystal defects and unsatisfactory detection results.

Description

Technical Field

[0001] This utility model relates to the field of photovoltaic module manufacturing technology, and more specifically, to a twin defect detection device. Background Technology

[0002] Currently, the manufacturing of crystalline silicon wafers is a key technological step in the production of photovoltaic modules. Crystal defects refer to regions in the crystal structure where the atomic arrangement deviates from an ideal, perfect crystal, and they have a significant impact on the physical and chemical properties of the crystal (such as mechanical properties, conductivity, and diffusion). In the manufacturing process of photovoltaic cells, twinning, as a common defect in polycrystalline silicon photovoltaic cells, significantly reduces cell efficiency and reliability.

[0003] However, existing detection technologies generally use unidirectional illumination of the silicon wafer. However, unidirectional illumination makes it difficult to effectively detect twin defects under high-speed conditions, and may even fail to detect twin defects at all, resulting in unsatisfactory detection results. Utility Model Content

[0004] The main objective of this invention is to provide a crystal defect detection device to solve the technical problem in existing solar cell crystal defect detection devices that use unidirectional irradiation of the silicon wafer, which makes it difficult to effectively detect twin defects under high-speed motion, or even fail to detect twin defects at all, resulting in unsatisfactory detection effects.

[0005] To achieve the above objectives, this utility model provides a twinning defect detection device for detecting twinning defects in silicon wafers. The twinning defect detection device includes:

[0006] A conveyor belt extends along a first direction for conveying silicon wafers to be tested along the first direction.

[0007] At least two light source assemblies are provided, each of which is located on the outer periphery of the inspection station and above the conveyor belt. The projected length of the straight-line distance L between the center of the emitting surface of each light source assembly and the center of the silicon wafer to be inspected at the inspection station is 380-600 mm on the horizontal plane and 500-800 mm on the vertical plane. The extension direction of the light source assembly is inclined relative to the conveying direction of the silicon wafer to be inspected, and the emitting surface of the light source assembly is inclined relative to the plane on which the silicon wafer to be inspected is located.

[0008] A camera, positioned above the conveyor belt and facing the silicon wafer to be inspected, is used to acquire image information of the silicon wafer.

[0009] In some embodiments, the angle between the extending direction of the light source assembly and the conveying direction of the silicon wafer to be tested is 30°-60°.

[0010] In some embodiments, the angle between the light-emitting surface of the light source assembly and the plane of the silicon wafer to be tested is 30°-60°.

[0011] In some embodiments, the angle between the extending direction of the light source assembly and the conveying direction of the silicon wafer to be tested is 30°-60°, and the angle between the emitting surface of the light source assembly and the plane where the silicon wafer to be tested is located is 30°-60°.

[0012] In some embodiments, the twin defect detection device includes four light source components. The four light source components are arranged in a circular array around the camera with the optical axis of the camera lens as the axis. The straight-line distance from the center of the light-emitting surface of the four light source components to the optical axis is equal. The angle formed between the extension direction of any light source component and the transport direction of the silicon wafer to be tested is 40°-50°. During twin defect detection, the four light source components emit light sequentially to irradiate the silicon wafer to be tested from different directions.

[0013] In some embodiments, the twin defect detection device includes two light source assemblies and a rotation drive. The two light source assemblies are symmetrically distributed about a first vertical plane, and the straight-line distance from the center of the light-emitting surface of the two light source assemblies to the first vertical plane is equal. Alternatively, the two light source assemblies are symmetrically distributed about a second vertical plane, and the straight-line distance from the center of the light-emitting surface of the two light source assemblies to the second vertical plane is equal. The first vertical plane passes through the optical axis of the camera lens and is parallel to the extension direction of the conveyor belt, while the second vertical plane passes through the optical axis of the camera lens and is perpendicular to the extension direction of the light source assemblies.

[0014] Two light source assemblies are fixedly mounted on the drive end of the rotary drive unit via a first mounting plate. The rotary drive unit is configured to drive the two light source assemblies to rotate around the optical axis until the angle formed between the extension direction of the two light source assemblies and the conveying direction of the silicon wafer to be tested is 40°-50°. The two light source assemblies emit light in sequence to irradiate the silicon wafer to be tested from different directions.

[0015] In some embodiments, the light source assembly is an LED collimated light source, and the light source assembly includes at least two sets of LED bead rows and a housing, with each set of LED bead rows disposed within the housing;

[0016] All the LED rows are arranged side by side along the height of the housing, and each group of LED rows includes several LEDs that are evenly spaced along the extension direction of the light source assembly.

[0017] In some embodiments, the light emitted by the light source component is blue light with a wavelength of 400nm-500nm.

[0018] In some embodiments, the twin defect detection device further includes a cooling fan disposed around the light source assembly, and the number of cooling fans is greater than or equal to the number of light source assemblies.

[0019] In some embodiments, the twin defect detection device further includes:

[0020] frame;

[0021] The first mounting assembly allows the camera to be height-adjustably mounted on the frame.

[0022] The number of second mounting components is the same as the number of light source components, and the light source components are mounted on the rack in an angle-adjustable and / or height-adjustable manner via the second mounting components;

[0023] The outer casing is located on the outer periphery of the frame, so that the light source assembly, camera, first mounting assembly and second mounting assembly are all located inside the outer casing.

[0024] In some embodiments, the first mounting component includes a first column, a slider that can slide up and down along the first column, and a camera fixedly mounted on the slider.

[0025] In some embodiments, the second mounting assembly includes a second column, a mounting base that can slide up and down and rotate along the second column, and a second mounting plate fixedly mounted on the mounting base. The second mounting plate has an arc-shaped hole. The light source assembly is fixedly mounted at different positions in the arc-shaped hole to adjust the angle between the light-emitting surface of the light source assembly and the plane where the silicon wafer to be tested is located. The mounting base is fixedly mounted at different heights on the second column to adjust the mounting height of the light source assembly. The mounting base is fixedly mounted on the second column by rotating at different angles to adjust the angle formed between the extension direction of the light source assembly and the conveying direction of the silicon wafer to be tested.

[0026] In some embodiments, the twin defect detection device further includes a first straightening section and a second straightening section symmetrically arranged on both sides of the conveyor belt. The first straightening section and the second straightening section straighten the silicon wafer to be tested passing through the conveyor belt. Both the first straightening section and the second straightening section are straightening belts or straightening plates.

[0027] By employing the technical solution of this utility model, a conveyor belt transports the silicon wafer to be inspected to the inspection station. The conveyor belt can continuously transport the silicon wafer to be inspected, improving transportation efficiency. At least two light source components are set up. The linear distance L between the center of the emitting surface of each light source component and the center of the silicon wafer to be inspected at the inspection station has a projected length of 380-600mm on the horizontal plane and 500-800mm on the vertical plane. The extension direction of the light source components is inclined relative to the transport direction of the silicon wafer to be inspected, and the emitting surface of the light source components is inclined relative to the plane where the silicon wafer is located. By installing the light source components in a specific posture, the residual light from the light source components illuminates the silicon wafer, ensuring that the focusing part of the light source components does not illuminate the silicon wafer to be inspected, thus avoiding overexposure caused by the focusing part of the light source components illuminating the silicon wafer to be inspected. This results in clearer image information of twin defects on the silicon wafer to be inspected. Furthermore, by setting up at least two light source components to emit light sequentially onto the silicon wafer to be inspected, multiple, multi-angle irradiation of the silicon wafer to be inspected can be quickly achieved even at high speeds, making the inspection process more efficient. Attached Figure Description

[0028] The accompanying drawings, which form part of this application, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an undue limitation of the present invention. In the drawings:

[0029] Figure 1 A perspective view of the crystal defect detection device according to the present invention is shown;

[0030] Figure 2 A top view of the crystal defect detection device according to the present invention is shown;

[0031] Figure 3 A schematic diagram of the external structure of the crystal defect detection device according to the present invention is shown;

[0032] Figure 4 A perspective view of the light source assembly and the second mounting assembly according to the present invention is shown;

[0033] Figure 5 A perspective view of the light source assembly and the second mounting assembly according to the present invention is shown from another angle.

[0034] The above figures include the following reference numerals:

[0035] 1. Conveyor belt; 11. Inspection station;

[0036] 2. Light source assembly; 21. LED array; 211. LED; 22. Housing;

[0037] 3. Camera;

[0038] 4. Cooling fan;

[0039] 5. Rack;

[0040] 6. First mounting component; 61. First column; 62. Slider;

[0041] 7. Second mounting component; 71. Second column; 72. Mounting base; 721. Notch; 73. Arc-shaped hole; 74. Guide rod; 75. Second mounting plate;

[0042] 8. Outer cover;

[0043] 9. First Regulation Section;

[0044] 10. Second Regulation Department;

[0045] 100. Silicon wafer to be tested;

[0046] 200. First vertical plane;

[0047] 300. Second vertical plane. Detailed Implementation

[0048] Embodiments of this application provide a twin defect detection device for detecting twin defects in silicon wafers. Please refer to [link / reference]. Figures 1 to 5 The twin defect detection device includes a conveyor belt 1, at least two light source assemblies 2, and a camera 3. The conveyor belt 1 extends along a first direction for conveying the silicon wafer 100 to be inspected along the first direction. Each light source assembly 2 is disposed on the outer periphery of the inspection station 11 and above the conveyor belt 1. The linear distance L between the center of the light-emitting surface of each light source assembly 2 and the center of the silicon wafer 100 to be inspected at the inspection station 11 has a projected length of 380-600 mm on the horizontal plane and a projected length of 500-800 mm on the vertical plane. The extending direction of the light source assembly 2 is inclined relative to the conveying direction of the silicon wafer 100 to be inspected, and the light-emitting surface of the light source assembly 2 is inclined relative to the plane on which the silicon wafer 100 to be inspected is located. The camera 3 is located above the conveyor belt 1 and facing the silicon wafer 100 to be inspected. The camera 3 is used to acquire image information of the silicon wafer 100 to be inspected.

[0049] It should be noted that the emitting surface of the light source component 2 refers to the side of the light source component 2 that directly emits light, and the extension direction of the light source component 2 refers to the direction in which its own length points. Specifically, the conveyor belt 1 is used to transport the silicon wafer to be inspected to the inspection station 11, where the light source component 2 illuminates the silicon wafer 100 at the inspection station 11 to provide a suitable lighting environment for detecting twin defects, and then the camera 3 acquires image information of the silicon wafer 100. Here, the light source component 2 is an LED collimated light source, which has a built-in collimator that converts the light emitted by the LED collimated light source into a parallel beam that illuminates the silicon wafer.

[0050] Here, the projected length of the straight-line distance L between the center of the emitting surface of each light source component 2 and the center of the silicon wafer 100 to be inspected at the inspection station 11 is set to 380-600mm on the horizontal plane, and the projected length of the straight-line distance L on the vertical plane is set to 500-800mm. The extension direction of the light source component 2 is inclined relative to the conveying direction of the silicon wafer 100 to be inspected, and the emitting surface of the light source component 2 is inclined relative to the plane where the silicon wafer 100 to be inspected is located. This setting allows the peripheral light of the light source component 2 to illuminate the silicon wafer 100 to be inspected, avoiding overexposure caused by the focusing part of the light source component 2 directly illuminating the silicon wafer 100 to be inspected. This allows the camera 3 to acquire a clear image and improves the accuracy of the inspection. In addition, by combining the conveyor belt 1 to transport the silicon wafer 100 to be tested, after the silicon wafer 100 to be tested is transported to the testing station 11, at least two light source components 2 can sequentially irradiate the silicon wafer 100 to be tested from different directions. After the camera 3 takes a picture, the conveyor belt 1 can directly drive the silicon wafer 100 to be tested to continue to be transported. There is no need to rotate the silicon wafer during the testing process. The silicon wafer can be moved and stopped at will, which has high testing efficiency.

[0051] It should be noted that the focusing portion of light source component 2 refers to the parallel beam emitted by the LED collimated light source. The peripheral light of light source component 2 refers to the scattered or diffracted light other than the parallel beam of the LED collimated light source.

[0052] Optionally, the angle formed between the extending direction of the light source assembly 2 and the conveying direction of the silicon wafer 100 to be tested is 30°-60°. Wherein, the angle formed between the extending direction of the light source assembly 2 and the conveying direction of the silicon wafer 100 to be tested is α (e.g., ...). Figure 2 As shown in the figure, by controlling the angle of α between 30° and 60°, and taking into account the characteristics of twin defects, it is helpful to better image the twin defects in the silicon wafer to be inspected at the inspection station.

[0053] Optionally, the angle between the emitting surface of the light source assembly 2 and the plane of the silicon wafer 100 to be tested is 30°-60°. Controlling the angle between the emitting surface of the light source assembly 2 and the plane of the silicon wafer 100 to be tested within 30°-60° allows the light source assembly 2 to illuminate the silicon wafer at the testing station with an appropriate amount of residual light, better adapting to the special lighting requirements during twin defect imaging, improving imaging clarity, and further enhancing testing accuracy.

[0054] Optionally, the angle between the extension direction of the light source assembly 2 and the conveying direction of the silicon wafer 100 to be tested is 30°-60°, and the angle between the light-emitting surface of the light source assembly 2 and the plane of the silicon wafer 100 to be tested is 30°-60°.

[0055] Furthermore, the angle formed between the extending direction of the light source component 2 and the conveying direction of the silicon wafer 100 to be tested is 40°-50°. By controlling the angle α to be between 40°-50°, the imaging clarity of twin defects can be further improved. In this embodiment, the twin defect detection device includes four light source components 2, which are arranged in a circular array around the camera 3 with the optical axis of the lens as the axis. The straight-line distance from the center of the light-emitting surface of the four light source components 2 to the optical axis is equal. The angle formed between the extending direction of any one light source component 2 and the conveying direction of the silicon wafer 100 to be tested is 40°-50°. During twin defect detection, the four light source components 2 emit light sequentially to illuminate the silicon wafer 100 to be tested from different directions.

[0056] Here, the four light source components 2 are arranged in a circular array with the optical axis of the camera 3 lens as the axis. This reduces the illumination blind zone during the inspection process, ensuring that any part of the silicon wafer 100 under inspection can be directly or indirectly illuminated by at least one light source component 2. Even if twin defects are located at the corners of the silicon wafer, they can be compensated for by the other light source components 2 in the circular array, ensuring that every area of ​​the silicon wafer 100 under inspection receives sufficient illumination. This effectively prevents the missed detection of twin defects and improves the accuracy of twin defect detection. Furthermore, since twin defects exhibit different characteristics under different angles of light, the four light source components 2 emit light sequentially, illuminating the silicon wafer 100 under inspection from different directions. The detection results of the four light source components 2 can be mutually verified, thereby reducing errors and improving the comprehensiveness and accuracy of the inspection. When illuminating the silicon wafer 100 under inspection located at the inspection station 11, the four light source components 2 emit light sequentially (i.e., only one light source component 2 emits light at a time, and the four light source components 2 emit light sequentially) to prevent other light source components 2 from emitting light simultaneously and interfering with the inspection.

[0057] Specifically, after adjusting the position of the light source assembly 2 to a preset position suitable for the silicon wafer 100 to be inspected, the conveyor belt 1 transports the silicon wafer 100 to be inspected to the inspection station 11. Then, the four light source assemblies 2 emit light in sequence to illuminate the silicon wafer 100 to be inspected. After each light source assembly 2 is illuminated, the camera 3 will capture the image information of this capture. The camera 3 can be replaced by other devices with image information acquisition functions.

[0058] In another embodiment, the twin defect detection device includes two light source components 2 and a rotary drive. The two light source components 2 are symmetrically distributed about a first vertical plane 200, and the straight-line distance from the center of the light-emitting surface of the two light source components 2 to the first vertical plane 200 is equal; or the two light source components 2 are symmetrically distributed about a second vertical plane 300, and the straight-line distance from the center of the light-emitting surface of the two light source components 2 to the second vertical plane 300 is equal. The first vertical plane 200 passes through the optical axis of the lens of the camera 3 and is parallel to the extension direction of the conveyor belt 1. The second vertical plane 300 passes through the optical axis of the lens of the camera 3 and is perpendicular to the extension direction of the light source components 2. The two light source components 2 are fixedly mounted on the drive end of the rotary drive by a first mounting plate. The rotary drive is configured to drive the two light source components 2 to rotate around the optical axis until the angle formed between the extension direction of the two light source components 2 and the conveying direction of the silicon wafer 100 to be tested is 40°-50°. The two light source components 2 emit light sequentially to irradiate the silicon wafer 100 to be tested from different directions.

[0059] Here, two light source components 2 are symmetrically distributed about the first vertical plane 200 or the second vertical plane 300. The two light source components 2 sequentially illuminate the silicon wafer 100 under test at the first position, and then, by rotating the drive component, change their positions to the second position and illuminate the silicon wafer 100 again sequentially. By setting two light source components 2 and a rotation drive component, multi-directional illumination of the silicon wafer 100 under test can be achieved with fewer light source components 2 compared to setting four. Here, the two light source components 2 at the first position and the two light source components 2 at the second position are symmetrically arranged along their respective vertical planes. The rotation drive component can continuously adjust the position of the light source components 2, ensuring that the light source components 2 illuminate the silicon wafer at an optimal angle (e.g., 40°-50°). Here, two light source components 2 are symmetrically arranged with the first vertical surface 200 or the second vertical surface 300, and the straight-line distance from the center of the light-emitting surface of the two light source components 2 to the first vertical surface 200 is equal. The camera 3 is positioned in the same position as the two light source components 2, ensuring that the two light source components 2 produce similar effects when illuminating the silicon wafer 100 to be tested, and reducing the detection deviation caused by improper position of one side of the light source component 2.

[0060] Specifically, the rotary drive assembly can be a motor, a motor and gear rack, a motor and synchronous belt and synchronous pulley, a motor and cam, etc. Those skilled in the art can realize the function of the rotary drive assembly based on existing transmission mechanisms, and will not be described in detail here.

[0061] Specifically, after adjusting the position of the light source component 2 to a preset position suitable for the silicon wafer 100 to be tested, the conveyor belt 1 transports the silicon wafer 100 to be tested to the testing station 11. Then, the two light source components 2 emit light in sequence at the first position to irradiate the silicon wafer 100 to be tested. After the two light source components 2 are rotated to the second position by the rotation drive component, the two light source components 2 emit light in sequence to irradiate the silicon wafer 100 to be tested. After each light source component 2 is irradiated, the camera 3 will collect the image information captured in this shooting.

[0062] In this embodiment, as Figure 4 As shown, the light source assembly 2 is an LED collimated light source. The LED collimated light source can reduce the diffusion of the light spot and improve the concentration of the illumination, enabling the camera 3 to receive a clear image. The light source assembly 2 includes at least two sets of LED bead rows 21 and a housing 22, with each LED bead row 21 housed within the housing 22. All LED bead rows 21 are arranged side-by-side along the height direction of the housing 22, and each set of LED bead rows 21 includes several LED beads 211 evenly spaced along the extension direction of the light source assembly 2. The LED bead rows 21, composed of multiple LED beads 211, can improve the light intensity, and the presence of multiple LED beads 211 in each set of LED bead rows 21 can produce continuous, uninterrupted illumination, ensuring overall light intensity and coverage. The LED beads 211 within the LED collimated light source can also be configured in other quantities and arrangements.

[0063] In this embodiment, the light emitted by the light source component 2 is blue light with a wavelength of 400nm-500nm. Specifically, the wavelengths of the light emitted by the light source component 2 include 400nm and 500nm. Because blue light has a shorter wavelength, within the range of 400nm to 500nm, it can better stimulate the reflective properties of the silicon wafer material, increasing the clarity of twin defects.

[0064] In this embodiment, as Figure 1 As shown, the twin defect detection device also includes a cooling fan 4, which is disposed around the periphery of the light source assembly 2, and the number of cooling fans 4 is greater than or equal to the number of light source assemblies 2. The cooling fans 4 provide heat dissipation for the light source assembly 2, thereby improving its lifespan. In other embodiments, the cooling fan 4 can be replaced with other heat dissipation devices with the same function.

[0065] In this embodiment, as Figure 1 , 3As shown, the twin defect detection device also includes a frame 5, a first mounting component 6, a second mounting component 7, and an outer cover 8. The outer cover 8 is installed around the frame 5, so that the light source component 2, the camera 3, the first mounting component 6, and the second mounting component 7 are all located inside the outer cover 8, which serves as a safety protection function.

[0066] The camera 3 is height-adjustably mounted on the frame 5 via the first mounting component 6, which facilitates adjusting the height position of the camera 3 and ensures that the field of view of the camera 3 is in focus with the detection surface of the silicon wafer 100 to be inspected.

[0067] Specifically, the first mounting component 6 includes a first column 61 and a slider 62 that can slide up and down along the first column 61. The camera 3 is fixedly mounted on the slider 62. Sliding the slider 62 along the height direction of the first column 61 will adjust the position of the camera 3. After adjustment, the first column 61 and the slider 62 can be fixed with bolts to ensure the installation reliability of the camera 3.

[0068] Furthermore, the number of second mounting components 7 is the same as the number of light source components 2. Each light source component 2 is mounted on the rack 5 at an adjustable angle via the second mounting components 7 to change the tilt angle of the light source component 2, and the light source component 2 is mounted on the rack 5 at an adjustable height via the second mounting components 7 to suit different testing requirements (e.g., different specifications of the silicon wafer 100 to be tested result in different testing requirements).

[0069] Specifically, such as Figure 4 As shown, the second mounting assembly 7 includes a second column 71, a mounting base 72 that can slide up and down and rotate along the second column 71, and a second mounting plate 75 fixedly mounted on the mounting base 72. The second mounting plate 75 has an arc-shaped hole 73. The light source assembly 2 is provided with a guide rod 74. The mounting base 72 and the second column 71 are slidably mounted up and down to change the height position of the light source assembly 2. The light source assembly 2 moves in the arc-shaped hole 73 through the guide rod 74 to change the position of the light source assembly 2 in the arc-shaped hole 73, thereby adjusting the angle between the light-emitting surface of the light source assembly 2 and the plane of the silicon wafer 100 to be tested. This ensures the flexibility of the position adjustment of the light source assembly 2. For different testing needs, such as different silicon wafer specifications, changing the position of the light source assembly 2 is more convenient and faster.

[0070] Furthermore, such as Figure 5 As shown, the mounting base 72 has a notch 721, which can reduce the friction between the two when the mounting base 72 slides up and down along the second column 71, making the sliding smoother. After the position adjustment of the mounting base 72 on the second column 71 is completed, the second column 71 and the mounting base 72 can be fixed by bolts passing through the side of the mounting base 72 near the notch 721.

[0071] In this embodiment, the silicon wafer is transported to the inspection station 11 via the conveyor belt 1, enabling rapid and continuous transport of the silicon wafer and thus improving inspection efficiency. The camera 3 is positioned above the conveyor belt 1, allowing it to directly target the silicon wafer 100 to be inspected and capture image information of the wafer.

[0072] In this embodiment, the twin defect detection device further includes a first straightening section 9 and a second straightening section 10 symmetrically arranged on both sides of the conveyor belt 1. Specifically, when the silicon wafer 100 to be tested moves along the conveyor belt 1, it is affected by slight vibrations during the conveying process, which may cause positional deviation. The first straightening section 9 and the second straightening section 10 straighten the silicon wafer 100 to be tested passing on the conveyor belt 1, ensuring that the position and orientation of the silicon wafer are accurate and without deviation during the transmission process. This helps to improve the positional consistency of the silicon wafer when it enters the detection station 11 and reduces detection errors caused by silicon wafer swaying or positional instability.

[0073] Specifically, both the first straightening section 9 and the second straightening section 10 are straightening belts or straightening plates. The first straightening section 9 and the second straightening section 10 are symmetrically arranged on both sides of the conveyor belt 1, with a certain width of distance between them. The first straightening section 9 and the second straightening section 10 form a receiving space. The width of this receiving space should be slightly larger than the width of the silicon wafer 100 to be tested, so that the silicon wafer 100 can pass smoothly, while the first straightening section 9 and the second straightening section 10 can apply a certain constraint force to the silicon wafer 100. The first straightening section 9 and the second straightening section 10, by contacting both sides of the silicon wafer, use friction or geometric constraint force to correct the position of the silicon wafer 100 to be tested, ensuring that each silicon wafer 100 is consistently positioned when conveyed to the testing station 11.

[0074] The above-described embodiments of this utility model use a conveyor belt to transport the silicon wafer to be tested to the testing station. The conveyor belt can continuously transport the silicon wafer to be tested, improving transportation efficiency. At least two light source components are provided. The linear distance L between the center of the emitting surface of each light source component and the center of the silicon wafer to be tested located at the testing station has a projected length of 380-600mm on the horizontal plane and a projected length of 500-800mm on the vertical plane. The extension direction of the light source component is inclined relative to the transport direction of the silicon wafer to be tested, and the emitting surface of the light source component is inclined relative to the plane where the silicon wafer to be tested is located. The residual light of the light source component 2 is used to illuminate the silicon wafer, so that the focusing part of the light source component 2 does not illuminate the silicon wafer to be tested 100, avoiding the overexposure phenomenon caused by the focusing part of the light source component 2 illuminating the silicon wafer to be tested 100, making the twin defect image information on the silicon wafer to be tested 100 clearer. Furthermore, at least two light source components 2 are set up to emit light sequentially to illuminate the silicon wafer to be tested. As the silicon wafer is continuously transported, it can also quickly achieve multiple and multi-angle irradiation of the silicon wafer to be tested 100, making the testing process more efficient.

[0075] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A twinning defect detection device for detecting twinning defects in silicon wafers, characterized in that, The twin defect detection device includes: A conveyor belt, which extends along a first direction for conveying silicon wafers to be tested along the first direction; At least two light source assemblies are provided, each of which is disposed on the outer periphery of the inspection station and above the conveyor belt. The linear distance L between the center of the emitting surface of each light source assembly and the center of the silicon wafer to be inspected at the inspection station has a projected length of 380-600 mm on the horizontal plane and a projected length of 500-800 mm on the vertical plane. The extension direction of the light source assembly is inclined relative to the conveying direction of the silicon wafer to be inspected, and the emitting surface of the light source assembly is inclined relative to the plane on which the silicon wafer to be inspected is located. A camera is positioned above the conveyor belt and facing the silicon wafer to be inspected, and the camera is used to acquire image information of the silicon wafer to be inspected.

2. The twinning defect detection device according to claim 1, characterized in that, The angle formed between the extending direction of the light source assembly and the conveying direction of the silicon wafer to be tested is 30°-60°; and / or The angle between the light-emitting surface of the light source assembly and the plane of the silicon wafer to be tested is 30°-60°.

3. The twinning defect detection device according to claim 1, characterized in that, The twin defect detection device includes four light source components. The four light source components are arranged in a circular array around the camera with the optical axis of the camera lens as the axis. The straight-line distance from the center of the light-emitting surface of the four light source components to the optical axis is equal. The angle formed between the extension direction of any one of the light source components and the transport direction of the silicon wafer to be tested is 40°-50°. During twin defect detection, the four light source components emit light sequentially to irradiate the silicon wafer to be tested from different directions.

4. The twinning defect detection device according to claim 1, characterized in that, The twin defect detection device includes two light source components and a rotation drive component. The two light source components are symmetrically distributed about a first vertical plane and the straight-line distance from the center of the light-emitting surface of the two light source components to the first vertical plane is equal. Alternatively, the two light source components are symmetrically distributed about a second vertical plane and the straight-line distance from the center of the light-emitting surface of the two light source components to the second vertical plane is equal. The first vertical plane passes through the optical axis of the camera lens and is parallel to the extension direction of the conveyor belt; the second vertical plane passes through the optical axis of the camera lens and is perpendicular to the extension direction of the light source assembly. The two light source assemblies are fixedly mounted on the drive end of the rotary drive member via a first mounting plate. The rotary drive member is configured to drive the two light source assemblies to rotate around the optical axis until the angle formed between the extension direction of the two light source assemblies and the conveying direction of the silicon wafer to be tested is 40°-50°. The two light source assemblies emit light sequentially to irradiate the silicon wafer to be tested from different directions.

5. The twinning defect detection device according to claim 1, characterized in that, The light source assembly is an LED collimated light source, and the light source assembly includes at least two sets of lamp bead rows and a housing, with each set of lamp bead rows disposed within the housing; All the lamp bead rows are arranged side by side along the height direction of the housing, and each group of lamp bead rows includes several lamp beads that are evenly spaced along the extension direction of the light source assembly.

6. The twinning defect detection device according to claim 1, characterized in that, The light emitted by the light source component is blue light with a wavelength of 400nm-500nm.

7. The twinning defect detection device according to claim 1, characterized in that, The twin defect detection device further includes a cooling fan, which is disposed around the light source assembly, and the number of cooling fans is greater than or equal to the number of light source assemblies.

8. The twinning defect detection device according to claim 1, characterized in that, The twin defect detection device also includes: frame; A first mounting assembly is used to mount the camera on the frame in a height-adjustable manner. The number of second mounting components is the same as the number of light source components, and the light source components are mounted on the frame in an angle-adjustable and / or height-adjustable manner via the second mounting components; An outer cover is provided on the outer periphery of the frame, such that the light source assembly, the camera, the first mounting assembly, and the second mounting assembly are all located inside the outer cover.

9. The twinning defect detection device according to claim 8, characterized in that, The first mounting assembly includes a first column, a slider that can slide up and down along the first column, and the camera is fixedly mounted on the slider; and / or, The second mounting assembly includes a second column, a mounting base that can slide up and down and rotate along the second column, and a second mounting plate fixedly mounted on the mounting base. The second mounting plate has an arc-shaped hole. The light source assembly is fixedly mounted at different positions in the arc-shaped hole to adjust the angle between the light-emitting surface of the light source assembly and the plane where the silicon wafer to be tested is located. The mounting base is fixedly mounted at different heights on the second column to adjust the mounting height of the light source assembly. The mounting base is fixedly mounted on the second column by rotating at different angles to adjust the angle formed between the extension direction of the light source assembly and the conveying direction of the silicon wafer to be tested.

10. The twinning defect detection device according to any one of claims 1-9, characterized in that, The twin defect detection device further includes a first straightening section and a second straightening section symmetrically arranged on both sides of the conveyor belt. The first straightening section and the second straightening section straighten the silicon wafer to be tested passing through the conveyor belt. Both the first straightening section and the second straightening section are straightening belts or straightening plates.

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