Wafer edge searching and code scanning method and device

Abstract

The invention discloses a wafer edge searching and code scanning method and device, and the method comprises the steps: adjusting the positions of the center of a reference wafer and a positioning part, enabling the center of the reference wafer to coincide with a mark point in a calibration station, and enabling the positioning part of the reference wafer to face a set direction; focusing the shooting visual angle on the positioning part of the reference wafer, and fixing the shooting visual angle; shooting the wafer identifier at the positioning part of the reference wafer, and setting a position deviation range based on the position of the wafer identifier of the reference wafer; replacing the reference wafer with a to-be-measured wafer, adjusting the circle center of the to-be-measured wafer to coincide with the mark point, and enabling the positioning part of the to-be-measured wafer to face a set direction; and shooting the wafer identifier at the positioning part of the to-be-detected wafer, and if the position of the wafer identifier of the to-be-detected wafer is within the position deviation range, detecting the precision of the wafer identifier of the to-be-detected wafer. According to the method, the wafer identification precision is detected while edge searching and positioning are performed on the wafer, and the production efficiency of the wafer is improved.

Description

Technical Field

[0001] The present application relates to the technical field of silicon carbide sorting, and in particular to a wafer edge finding and code scanning method and device. Background Art

[0002] Silicon carbide (SiC) wafers, as an important semiconductor material, are widely used in electronic devices under extreme working conditions such as high power, high frequency, and high temperature. In the manufacturing and processing of wafers, sorting them according to their size, shape, and quality is an important link to ensure product quality. Therefore, it is necessary to detect wafers to ensure the consistency of each wafer and the accuracy of detection.

[0003] In current production practices, each wafer is usually laser-etched with a unique wafer identification (laser-etched code), and these laser-etched codes play a role in identification and tracking during wafer sorting and wafer detection. However, the existing technology usually only limits to simply scanning the laser-etched code and transmitting its information to the host computer system to monitor the subsequent process flow of the wafer, without detailed detection of the processing accuracy of the laser-etched code (i.e., whether the printed laser-etched code meets the factory standards). If the detection process for the processing accuracy of the laser-etched code is added, the production efficiency of the wafer will be reduced. Summary of the Invention

[0004] To solve the deficiencies of the existing technology, the purpose of the present application is to provide a wafer edge finding and code scanning method and device, which can perform edge finding and positioning on the wafer and detect the processing accuracy of the wafer identification.

[0005] To achieve the above purpose, the present application adopts the following technical solutions: In a first aspect, the present application provides a wafer edge finding and code scanning method, which includes: When the reference wafer is placed at the calibration station, adjust the position of the center of the reference wafer and the positioning part so that the center of the reference wafer coincides with the marking point in the calibration station, and the positioning part of the reference wafer faces the set direction; Focus the shooting perspective on the positioning part of the reference wafer and fix the shooting perspective; Shoot the wafer identification at the positioning part of the reference wafer, and set the position deviation range based on the position of the wafer identification of the reference wafer; Replace the reference wafer with the wafer to be tested, adjust the center of the wafer to be tested to coincide with the marking point in the calibration station, and the positioning part of the wafer to be tested faces the set direction; Shoot the wafer identification at the positioning part of the wafer to be tested. If the position of the wafer identification of the wafer to be tested is within the position deviation range, detect the accuracy of the wafer identification of the wafer to be tested.

[0006] Further, the method further includes: If the position of the wafer identification of the wafer to be measured is outside the position deviation range, determine that the wafer to be measured is a defective wafer.

[0007] Further, detect the accuracy of the wafer identification of the wafer to be measured, including: Based on the captured image, locate the center of the wafer to be measured, the positioning part, and the position of the wafer identification to obtain position data; Sample the size, edge position, and relative angle of the wafer to be measured to obtain edge data, where a reference direction is set at the calibration station, and the relative angle is the angle difference between the reference direction and the set direction; Fit the edge data with the positioning data, and compare the fitting result with the preset standard data to determine the accuracy of the wafer to be measured.

[0008] Further, before locating the center of the wafer to be measured, the positioning part, and the position of the wafer identification based on the captured image, it includes: Adjust the grayscale value of the captured image so that the difference between the grayscale value of the wafer identification of the wafer to be measured and the grayscale value of the image background is greater than the set grayscale value threshold.

[0009] Further, fitting the edge data with the positioning data, and comparing the fitting result with the preset standard data to determine the accuracy of the wafer to be measured, including: Draw a fitting curve representing the wafer to be measured based on the edge data and the positioning data; Compare the fitting curve with the standard data to obtain the fitting degree of the wafer to be measured; If the fitting degree is outside the preset threshold range, determine that the wafer to be measured is a defective wafer.

[0010] In a second aspect, the present application also provides a wafer edge finding and code scanning device, and the device includes: A support platform; A wafer calibrator, the wafer calibrator is installed on the support platform, a calibration station for placing the wafer is formed in the wafer calibrator, the wafer calibrator includes a detection unit and an adjustment platform, the adjustment platform is used to support the wafer to keep the wafer in the calibration station, the detection unit is used to detect the positions of the center of the wafer and the positioning part, and drive the adjustment platform according to the detection result to make the center coincide with the marked point in the calibration station, and the positioning part faces the set direction; A moving mechanism, the moving mechanism is installed on the support platform, and the moving mechanism has degrees of freedom of movement in at least two directions on the horizontal plane; A shooting and code reading mechanism, the shooting and code reading mechanism includes a camera and a code reader, the camera is installed on the moving mechanism and can move under the drive of the moving mechanism so that the shooting angle of the camera focuses on the positioning part, the camera is used to shoot the wafer identification located at the positioning part, and the code reader can read the wafer identification.

[0011] Furthermore, the wafer edge finding and code scanning device further includes a processing module, which is electrically connected to the detection unit. The detection unit is further configured to sample the size, edge position, and relative angle of the wafer. Among them, a reference direction is set at the calibration station, and the relative angle is the angle difference between the reference direction and the set direction. The processing module can generate edge data of the wafer according to the sampling results of the detection unit; The processing module can also locate the wafer identification, the center of the wafer, and the position of the positioning part based on the image captured by the camera to obtain position data, fit the edge data with the positioning data, and compare the fitting result with the preset standard data to determine the accuracy of the wafer identification.

[0012] Furthermore, the moving mechanism includes a mounting platform, a first moving component, and a second moving component. The mounting platform is fixed to the support platform. The first moving component is mounted on the mounting platform and can drive the second moving component to move along a first direction. The second moving component is mounted on the first moving component and can drive the camera to move along a second direction. The first direction is different from the second direction.

[0013] Furthermore, the first moving component includes a first guide rail and a first driving unit. The second moving component includes a second guide rail and a second driving unit. The first guide rail is fixed to the mounting platform. The second guide rail can move relative to the first guide rail along the first direction under the action of the first driving unit. The camera can move relative to the second guide rail along the second direction under the action of the second driving unit.

[0014] Furthermore, the photographing and code reading mechanism further includes a camera adjustment plate, which is connected to the second moving component, and the camera is mounted on the camera adjustment plate.

[0015] The wafer edge finding and code scanning method provided by this application fixes the position of the reference wafer, makes the center of the reference wafer coincide with the marking point in the calibration station, and the positioning part of the reference wafer faces the set direction, so as to obtain the shooting perspective of the positioning part of the reference wafer and determine the position deviation range in the subsequent detection process. Then, the reference wafer is replaced with the wafer to be measured, and the wafer identification of the wafer to be measured is photographed at the same shooting perspective, and it is judged whether the wafer identification of the wafer to be measured is within the position deviation range, so as to improve the detection accuracy of the wafer identification of the wafer to be measured, and complete the edge finding and positioning of the wafer to be measured when adjusting the position of the center and the positioning part of the wafer to be measured. Based on this method, while performing edge finding and positioning on the wafer, it realizes the detection of the accuracy of the wafer identification, improving the production efficiency of the wafer. Description of the Drawings

[0016] Figure 1 is a schematic structural diagram of the edge finding and code scanning device in the embodiment of this application; Figure 2 is Figure 1Enlarged view of location A; Figure 3 Schematic diagram of the first shooting angle of the edge-finding and code-scanning device in the embodiment of the present application; Figure 4 Schematic connection diagram of the processing module in the embodiment of the present application; Figure 5 Schematic diagram of the second shooting angle of the edge-finding and code-scanning device in the embodiment of the present application; Figure 6 is Figure 5 Enlarged view of location B; Figure 7 The first flow chart of the wafer edge-finding and code-scanning method in the embodiment of the present application; Figure 8 The second flow chart of the wafer edge-finding and code-scanning method in the embodiment of the present application.

[0017] Reference numerals: 100, edge-finding and code-scanning device; 10, support platform; 20, wafer calibrator; 21, detection unit; 22, adjustment platform; 30, moving mechanism; 31, mounting platform; 32, first moving component; 321, first guide rail; 322, first driving unit; 33, second moving component; 331, second guide rail; 332, second driving unit; 40, shooting and code-reading mechanism; 41, camera; 42, code reader; 43, camera adjustment plate. Detailed implementation manners

[0018] In order to enable those skilled in the art to better understand the solution of the present application, the technical solutions in the specific embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application.

[0019] It should be noted that the above-mentioned orientation nouns such as up, down, left, right, front, and back, or ordinal numbers such as "first" and "second" are introduced for the convenience of description based on the accompanying drawings of the specification, and do not mean any limitation on the order of the components. In addition, since the functions of some parts of the components provided in the above embodiments are the same, the present specification uses a unified naming method for these parts.

[0020] As Figure 1 shown, the present application provides a wafer edge-finding and code-scanning device 100, which includes a support platform 10, a wafer calibrator 20, a moving mechanism 30, and a shooting and code-reading mechanism 40. The wafer calibrator 20 is installed on the support platform 10, and a calibration station for placing the wafer is formed in the wafer calibrator 20. The moving mechanism 30 is installed on the support platform 10, and the moving mechanism 30 is used to drive the shooting and code-reading mechanism 40 to move, and the shooting and code-reading mechanism 40 is used to shoot the wafer in the calibration station.

[0021] The wafer edge finding and code scanning device 100 is configured with a loading unit. Among them, the loading unit includes a wafer basket 200 and a manipulator assembly 300. The wafer basket 200 is used to store wafers. The manipulator assembly 300 can grasp the wafers in the wafer basket 200 and transfer the wafers to the calibration station of the wafer calibrator 20. If it is necessary to adjust the position and orientation of the wafers in the wafer calibrator 20, it can also be achieved by the manipulator assembly 300.

[0022] As Figure 2 and 3 shown, as an implementation method, the wafer calibrator 20 includes a detection unit 21 and an adjustment platform 22. The adjustment platform 22 is located below the calibration station and is used to support the wafer to keep the wafer in the calibration station. The detection unit 21 is located above the calibration station. The detection unit 21 is used to detect the center of the wafer and the positioning part. Among them, the outer edge of the wafer has a wafer flat edge (also known as wafer flat groove, wafer groove, wafer V-groove). The wafer flat edge can be used as the positioning part of the wafer to determine the direction of the wafer.

[0023] In the specific detection process, the detection unit 21 detects the wafer placed on the adjustment platform 22, detects the center coordinate of the wafer and the position of the positioning part. The detection unit 21 compares the collected center coordinate of the wafer with the coordinate of the marking point 23 in the calibration station to determine the coordinate deviation. The detection unit 21 compares the orientation of the collected positioning part with the set direction to determine the direction deviation. Among them, a reference direction is set in the calibration station or the detection unit 21. In the embodiment of the present application, the set direction means that the positioning part forms a 90° angle with the reference direction in the horizontal direction. The detection unit 21 drives the adjustment platform 22 according to the coordinate deviation and the direction deviation to perform translation and rotation adjustment on the wafer, so that the center coincides with the marking point 23 in the calibration station and the positioning part faces the set direction.

[0024] Exemplarily, the detection unit 21 first collects the wafer image, and determines that the center coordinate of the wafer is (100.5, 200.3) pixels through an algorithm. The position of the marking point 23 in the calibration station is (100, 200) pixels, and the positioning part has a deviation of 5° from the set direction. The detection unit 21 feeds back these deviation data to the adjustment platform 22. Subsequently, the adjustment platform 22 performs translation and rotation adjustment on the wafer until the center of the wafer is accurately moved to the (100, 200) pixel position, and at the same time rotates the positioning part by 5° to make it consistent with the set direction.

[0025] In some alternative embodiments, the adjustment platform 22 is a circular platform and can rotate along its circumferential direction to adjust the orientation of the wafer so that the positioning portion of the wafer faces the set direction. When the wafer is placed at the calibration station, the center of the wafer needs to coincide with the marked point of the calibration station. The adjustment platform 22 has a degree of freedom of movement in the horizontal direction. If the center of the wafer does not coincide with the marked point of the calibration station, the adjustment platform 22 can also be driven to move in the horizontal direction so that the center of the wafer coincides with the marked point of the calibration station.

[0026] In some alternative embodiments, a processor unit is configured in the wafer calibrator 20. The processor unit is electrically connected to the detection unit 21 and the adjustment platform 22 respectively. The detection unit 21 is only used to collect the center coordinates of the wafer and the position of the positioning portion of the wafer, and transmit the collected data to the processor unit. The processor unit performs a specific comparison process and generates a signal representing the comparison result, and controls the adjustment platform 22 through the signal to perform translation and rotation adjustments on the wafer, so that the center coincides with the marked point in the calibration station and the positioning portion faces the set direction.

[0027] The moving mechanism 30 is installed on the support platform 10, and the moving mechanism 30 has degrees of freedom of movement in at least two directions on the horizontal plane.

[0028] Exemplarily, the moving mechanism 30 can at least move along a first direction and a second direction, where the first direction and the second direction refer to two independent and mutually orthogonal movement directions on the horizontal plane.

[0029] The photographing and code reading mechanism 40 includes a camera 41 and a code reader 42. The camera 41 is installed on the moving mechanism 30 and can move under the drive of the moving mechanism 30, so that the shooting angle of view of the camera 41 focuses on the positioning portion of the adjusted wafer at the calibration station and shoots the wafer identification located at the positioning portion. The code reader 42 can read the wafer identification of the wafer. Among them, the wafer identification is a laser engraving code engraved on the wafer.

[0030] Through the above settings, the wafer edge finding and code scanning device 100 detects the wafer identification while performing edge positioning on the wafer, realizes the detection of the accuracy of the wafer identification, and improves the production efficiency of the wafer.

[0031] To clearly illustrate the technical solution of the present application, the wafers are divided into reference wafers and wafers to be tested. The shooting angle position (i.e., the focal point position) of the camera 41 is determined by the reference wafers, and the shooting angle position of the camera 41 is kept unchanged, and then the wafer identification of the wafers to be tested is detected.

[0032] Specifically, a reference wafer as a reference is placed on the adjustment platform 22 by the manipulator assembly 300. The detection unit 21 detects the reference wafer located on the adjustment platform 22 to determine the center of the reference wafer and the position of the positioning portion. The adjustment platform 22 adjusts the reference wafer based on the detection result of the detection unit 21 to make the positioning portion of the reference wafer face the set direction. The adjustment platform 22 adjusts the reference wafer based on the detection result of the detection unit 21 to make the center of the reference wafer coincide with the marking point 23 in the calibration station. The moving mechanism 30 adjusts the camera 41 to make the shooting angle of the camera 41 focus on the positioning portion of the reference wafer and capture the wafer identification located at the positioning portion of the reference wafer. When the shooting angle of the camera 41 focuses on the wafer identification of the reference wafer, the shooting angle of the camera 41 remains fixed. The code reader 42 reads the wafer identification of the reference wafer.

[0033] As Figure 4 shown, in the embodiment of the present application, the wafer edge finding and code scanning device 100 further includes a processing module 50, and the processing module 50 is electrically connected to the camera 41. The processing module 50 is used to obtain the images captured by the camera 41, and these images contain the position information of multiple parts on the reference wafer. Among them, the multiple parts include the wafer identification of the reference wafer, the center of the reference wafer, and the positioning portion of the reference wafer. The processing module 50 can set the position deviation range according to the wafer identification of the reference wafer.

[0034] Further, the reference wafer is replaced with a wafer to be tested. If the center of the wafer to be tested coincides with the marking point in the calibration station and the positioning portion of the wafer to be tested faces the set direction, the camera 41 captures the wafer identification at the positioning portion of the wafer to be tested. It is judged whether the position of the wafer identification of the wafer to be tested is within the position deviation range. If the position of the wafer identification of the wafer to be tested is within the position deviation range, the accuracy of the wafer identification of the wafer to be tested is detected; if the position of the wafer identification of the wafer to be tested is outside the position deviation range, the wafer to be tested is calibrated as a defective wafer.

[0035] Through the above settings, it is possible to effectively detect the position and accuracy of the wafer identification of the wafer to be tested, which helps to ensure the accuracy and consistency of the subsequent detection process.

[0036] As an implementation method, the detection unit 21 is also used to sample the size, position and relative angle of the edge of the wafer to be tested, where the relative angle is the angle difference between the reference direction and the set direction. The processing module 50 is used to generate the edge data of the wafer according to the sampling result of the detection unit 21. The processing module 50 is also used to locate the wafer identification, the center and the position of the positioning portion of the wafer to obtain the positioning data, and fit the edge data with the positioning data, and compare the fitting result with the set standard data to determine the accuracy of the wafer identification.

[0037] With the above settings, the edge-finding and code-scanning device 100 integrates the functions of edge-finding and positioning of the integrated wafer and detection of the processing accuracy of the wafer identification, improving the detection efficiency of the wafer quality and reducing the detection cost.

[0038] Further, the processing module 50 is further configured to adjust the gray value of the image, so that the difference between the gray value of the wafer identification of the wafer and the gray value of the image background is greater than a set gray value threshold.

[0039] Exemplarily, the gray value of the wafer identification of the wafer to be measured is adjusted to 100, and the gray value of the background is adjusted to 50.

[0040] With the above settings, the contrast of the wafer identification in the image is improved, and the subsequent code-reading process can more accurately identify and locate the wafer identification of the wafer, improving the detection accuracy of the wafer identification of the wafer.

[0041] As Figure 5 and Figure 6 shown, as an implementation manner, the moving mechanism 30 includes a mounting platform 31, a first moving component 32, and a second moving component 33. The mounting platform 31 is fixed to the support platform 10 to support the moving mechanism 30 and ensure the stability of subsequent components. The first moving component 32 is mounted on the mounting platform 31 and can drive the second moving component 33 to move in the first direction. The camera 41 is mounted on the second moving component 33, and the second moving component 33 is mounted on the first moving component 32. The second moving component 33 can drive the camera 41 to move in the second direction.

[0042] Further, the first moving component 32 includes a first guide rail 321 and a first driving unit 322, and the second moving component 33 includes a second guide rail 331 and a second driving unit 332. The first guide rail 321 is fixed to the mounting platform 31. The second guide rail 331 can move relative to the first guide rail 321 in the first direction under the action of the first driving unit 322, and the camera 41 can move relative to the second guide rail 331 in the second direction under the action of the second driving unit 332.

[0043] Specifically, by driving the second guide rail 331 to move relative to the first guide rail 321 in the first direction by the first driving unit 322, the continuous and controllable movement of the second guide rail 331 in the first direction is realized, and further the positioning accuracy of the camera 41 in the first direction is guaranteed. By driving the camera 41 to move relative to the second guide rail 331 in the second direction by the second driving unit 332, the accurate movement of the camera 41 in the second direction is realized, so that the camera 41 has at least two degrees of freedom of movement in the horizontal plane and can reach any predetermined position in the horizontal plane, and further it can be ensured that the target area (such as the wafer identification of the reference wafer) is always within the field of view of the camera 41.

[0044] With the above settings, the moving mechanism 30 has high-precision and multi-degree-of-freedom positioning capabilities, providing a stable and reliable moving platform for the camera 41, ensuring that the camera 41 can always accurately focus on the target area during scanning or edge finding.

[0045] As Figure 3 shown, further, the photographing and code reading mechanism 40 further includes a camera adjustment plate 43. The camera adjustment plate 43 is connected to the second moving component 33. The camera 41 is mounted on the camera adjustment plate 43. The camera adjustment plate 43 serves to connect and fix the camera 41, and at the same time, the camera adjustment plate 43 is also used to adjust the distance between the camera 41 and the wafer.

[0046] As Figure 7 shown, the present application also provides a wafer edge finding and code scanning method, which includes the following steps: Step S601: When the reference wafer is placed on the calibration station, adjust the positions of the center of the reference wafer and the positioning part.

[0047] Exemplarily, place the reference wafer on the adjustment platform 22. Based on the detection unit 21 detecting the center of the reference wafer and the positioning part, the adjustment platform 22 can adjust the reference wafer in the calibration station according to the detection result of the detection unit 21, so that the center of the reference wafer coincides with the marked point in the calibration station, and the positioning part of the reference wafer faces the set direction. Among them, the outer edge of the reference wafer has a wafer flat edge (also known as a wafer flat groove, a wafer groove, a wafer V-groove), and the wafer flat edge can be used as the positioning part of the reference wafer to determine the direction of the reference wafer.

[0048] In some embodiments, due to the different wafer loading positions, the set direction can be flexibly adjusted according to the loading position.

[0049] Step S602: Focus the photographing perspective on the positioning part of the reference wafer and fix the photographing perspective.

[0050] Adjust the position of the camera 41 through the moving mechanism 30 so that the photographing perspective of the camera 41 focuses on the positioning part of the reference wafer. When the photographing perspective of the camera 41 focuses on the positioning part of the reference wafer, stop moving the camera 41, thereby fixing the photographing perspective of the camera 41.

[0051] It should be noted that during the subsequent detection process of the wafer to be measured, the photographing perspective of the camera 41 remains unchanged.

[0052] Step S603: Photograph the wafer identification located at the positioning part of the reference wafer, and set a position deviation range based on the position of the wafer identification of the reference wafer.

[0053] Step S604: Replace the reference wafer with the wafer to be measured, adjust the center of the wafer to be measured to coincide with the marking point in the calibration station, and the positioning part of the wafer to be measured faces the set direction.

[0054] Step S605: Take a picture of the wafer identification at the positioning part of the wafer to be measured. If the position of the wafer identification of the wafer to be measured is within the position deviation range, then detect the accuracy of the wafer identification of the wafer to be measured.

[0055] Exemplarily, taking the position of the wafer identification of the reference wafer as a reference, set a position deviation range of ±1 mm, that is, the deviation of the position of the wafer identification of the wafer to be measured from the position of the wafer identification of the reference wafer in the horizontal direction shall not exceed 1 mm.

[0056] In the embodiment of the present application, if the position of the wafer identification of the wafer to be measured is outside the position deviation range, then determine that the wafer to be measured is a defective wafer.

[0057] As Figure 8 shown, in some embodiments, Step S605: Detect the accuracy of the wafer identification of the wafer to be measured, including: Step S6051: Based on the captured image, locate the center of the wafer to be measured, the positioning part and the position of the wafer identification to obtain position data.

[0058] Exemplarily, the processing unit 50 can calculate the relative position between the center of the wafer to be measured and the positioning part according to the positioning part of the wafer to be measured and the size of the wafer to be measured, and adjust the wafer to be measured based on the relative position between the center and the positioning part to make the center of the wafer to be measured coincide with the marking point. In addition, the processing unit 50 combines the calculated center position of the wafer to be measured with the position of the positioning part and the wafer identification to obtain the position data of the wafer to be measured.

[0059] Step S6052: Sample the size, edge position and relative angle of the wafer to be measured to obtain edge data.

[0060] Wherein, a reference direction is set in the calibration station, and the relative angle is the angle difference between the reference direction and the set direction.

[0061] Step S6053: Fit the edge data with the positioning data, and compare the fitting result with the preset standard data to determine the accuracy of the wafer to be measured.

[0062] Exemplarily, the processing unit 50 can draw a fitting curve representing the wafer to be measured based on the edge data and the positioning data; compare the fitting curve with the standard data to obtain the fitting degree of the wafer to be measured; if the fitting degree is outside the preset threshold range, then determine that the wafer to be measured is a defective wafer.

[0063] In summary, by fixing the position of the reference wafer, making the center of the reference wafer coincide with the marked point in the calibration station, and orienting the positioning part of the reference wafer towards the set direction, the shooting perspective for shooting the positioning part of the reference wafer is obtained, and the position deviation range in the subsequent detection process is determined. Then, the reference wafer is replaced with the wafer to be tested, the wafer identification of the wafer to be tested is shot from the same shooting perspective, and it is determined whether the wafer identification of the wafer to be tested is within the position deviation range, thereby improving the detection accuracy of the wafer identification of the wafer to be tested. When adjusting the positions of the center and the positioning part of the wafer to be tested, the edge-finding positioning of the wafer to be tested is completed. Based on this method, while performing edge-finding positioning on the wafer, the detection of the accuracy of the wafer identification is achieved, and the production efficiency of the wafer is improved.

[0064] It should be understood that for those of ordinary skill in the art, improvements or transformations can be made according to the above description, and all such improvements and transformations should fall within the protection scope of the appended claims of this application.

Claims

1. A wafer edge finding and code scanning method, characterized in that The method includes: When the reference wafer is placed at the calibration station, adjust the positions of the center of the reference wafer and the positioning part so that the center of the reference wafer coincides with the marking point in the calibration station, and the positioning part of the reference wafer faces the set direction; Focus the shooting angle on the positioning part of the reference wafer and fix the shooting angle; Shoot the wafer identification at the positioning part of the reference wafer, and set the position deviation range based on the position of the wafer identification of the reference wafer; Replace the reference wafer with the wafer to be tested, adjust the center of the wafer to be tested to coincide with the marking point in the calibration station, and the positioning part of the wafer to be tested faces the set direction; Shoot the wafer identification at the positioning part of the wafer to be tested. If the position of the wafer identification of the wafer to be tested is within the position deviation range, detect the accuracy of the wafer identification of the wafer to be tested.

2. The wafer edge finding and bar code scanning method according to claim 1, wherein The method further includes: If the position of the wafer identification of the wafer to be tested is outside the position deviation range, determine that the wafer to be tested is a defective wafer.

3. The wafer edge finding and bar code scanning method according to claim 1, wherein The detection of the accuracy of the wafer identification of the wafer to be tested includes: Based on the captured image, locate the positions of the center of the wafer to be tested, the positioning part, and the wafer identification to obtain position data; Sample the size, edge position, and relative angle of the wafer to be tested to obtain edge data, wherein a reference direction is set in the calibration station, and the relative angle is the angle difference between the reference direction and the set direction; Fit the edge data with the position data, and compare the fitting result with the preset standard data to determine the accuracy of the wafer to be tested.

4. The wafer edge finding and bar code scanning method according to claim 3, wherein Before locating the positions of the center of the wafer to be tested, the positioning part, and the wafer identification based on the captured image, it includes: Adjust the gray value of the captured image so that the difference between the gray value of the wafer identification of the wafer to be tested and the gray value of the image background is greater than the set gray value threshold.

5. The wafer edge finding and bar code scanning method according to claim 3, wherein The fitting of the edge data with the position data, and the comparison of the fitting result with the preset standard data to determine the accuracy of the wafer to be tested includes: Draw a fitting curve representing the wafer to be tested based on the edge data and the position data; Compare the fitting curve with the standard data to obtain the fitting degree of the wafer to be tested; If the fitting degree is outside the preset threshold range, determine that the wafer to be tested is a defective wafer.

6. A wafer edge finding and code scanning device, characterized in that, It includes: A support platform (10); Wafer aligner (20), the wafer aligner (20) is installed on the support platform (10), a calibration station for placing the wafer is formed in the wafer aligner (20), the wafer aligner (20) includes a detection unit (21) and an adjustment platform (22), the adjustment platform (22) is used to support the wafer to keep the wafer in the calibration station, the detection unit (21) is used to detect the position of the center of the wafer and the positioning part, and drive the adjustment platform (22) according to the detection result to make the center of the circle coincide with the marked point in the calibration station, and the positioning part faces the set direction; Moving mechanism (30), the moving mechanism (30) is installed on the support platform (10), and the moving mechanism (30) has degrees of freedom of movement in at least two directions on the horizontal plane; Shooting and code reading mechanism (40), the shooting and code reading mechanism (40) includes a camera (41) and a code reader (42), the camera (41) is installed on the moving mechanism (30) and can move under the drive of the moving mechanism (30) to make the shooting angle of the camera (41) focus on the positioning part, the camera (41) is used to shoot the wafer identification located at the positioning part, and the code reader (42) can read the wafer identification.

7. The wafer edge finding and code scanning device according to claim 6, characterized in that The wafer edge finding and code scanning device further includes a processing module (50), the processing module (50) is electrically connected to the detection unit (21), and the detection unit (21) is further used to sample the size, edge position and relative angle of the wafer. Wherein, a reference direction is set in the calibration station, and the relative angle is the angle difference between the reference direction and the set direction. The processing module (50) can generate edge data of the wafer according to the sampling result of the detection unit (21); The processing module (50) can also position the wafer identification, the center of the wafer and the position of the positioning part based on the image taken by the camera (41) to obtain position data, fit the edge data with the positioning data, and compare the fitting result with the preset standard data to determine the accuracy of the wafer identification.

8. The wafer edge finding and code scanning device according to claim 6, characterized in that The moving mechanism (30) includes a mounting platform (31), a first moving component (32) and a second moving component (33), the mounting platform (31) is fixed to the support platform (10), the first moving component (32) is installed on the mounting platform (31) and can drive the second moving component (33) to move in a first direction, the second moving component (33) is installed on the first moving component (32) and can drive the camera (41) to move in a second direction, and the first direction is different from the second direction.

9. The wafer edge finding and code scanning device according to claim 8, characterized in that The first moving component (32) includes a first guide rail (321) and a first driving unit (322), the second moving component (33) includes a second guide rail (331) and a second driving unit (332), the first guide rail (321) is fixed to the mounting platform (31), the second guide rail (331) can move relative to the first guide rail (321) along the first direction under the action of the first driving unit (322), and the camera (41) can move relative to the second guide rail (331) along the second direction under the action of the second driving unit (332).

10. The wafer edge finding and code scanning device according to claim 8, wherein the photographing and code reading mechanism (40) further includes a camera adjustment plate (43), the camera adjustment plate (43) is connected to the second moving component (33), and the camera (41) is mounted on the camera adjustment plate (43).

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