A vision-based wafer edge location method, apparatus, and readable medium

Abstract

This invention relates to the field of semiconductor manufacturing and testing technology, specifically to a vision-based wafer edge-finding and positioning method, apparatus, and readable medium. The method includes the following steps: acquiring edge images of the wafer to be positioned using an image acquisition device; constructing a mechanical coordinate system based on the wafer in a standard position; performing edge point search and notch matching search on all edge images to determine the center of the circle to be positioned and the center of the notch to be positioned; unifying the coordinates of the center of the circle to be positioned and the center of the notch to be positioned and transforming them to the mechanical coordinate system; calculating the rotation angle based on the mechanical coordinates of the center of the circle to be positioned and the center of the notch to be positioned; and then controlling a rotation and translation platform to perform rotation and translation operations on the wafer to be positioned based on the center of the circle to be positioned and the rotation angle to adjust the wafer to be positioned to the standard position. The method proposed in this application solves the problems of multiple positioning and poor accuracy in the prior art by acquiring edge images and adjusting positioning in one step.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing and testing technology, specifically to a vision-based wafer edge location method, apparatus, and readable medium. Background Technology

[0002] During semiconductor manufacturing, wafers undergo significant positional changes within the cassette during transport between workshops or factories. Precise wafer positioning is a critical prerequisite for subsequent processes. For instance, wafers need to be pre-positioned before processes such as photolithography, etching, marking, quality inspection, and wafer transfer.

[0003] Currently, most mainstream wafer pre-positioning solutions rely on laser displacement sensors. The core principle is to drive the wafer to rotate around the central axis, emit laser light through a laser sensor on the edge of the wafer and receive the unblocked light, obtain the radial distance of the wafer edge at multiple angular positions based on the amount of laser obstruction, thereby obtaining the coordinates of the contour points, and finally obtain the wafer center coordinates by fitting the contour points. However, this solution has the following significant drawbacks: 1. Limited functionality: It can only achieve wafer center positioning and cannot directly obtain the position and angle information of the notch. It requires additional sensors or manual marking to assist, resulting in multiple positioning steps in the process, which is inefficient. 2. Weak anti-interference capability: Wafer edges often have abnormal laser occlusion due to processing defects such as burrs, chipping, and blue film protrusion, or the presence of contaminants such as particles and dust, generating a large number of noise points and seriously affecting the contour fitting accuracy. 3. High cost: Through-beam laser sensors require high-precision calibration, such as optical path collimation and temperature compensation. The purchase and maintenance costs of the sensors themselves are high, with the cost of a single sensor reaching tens of thousands of yuan, which is difficult to meet the needs of low-cost production lines. 4. Lack of result verification: There is no automatic verification mechanism after positioning. If the center coordinate deviation is caused by noise or sensor failure, it cannot be detected and corrected in time, which may lead to subsequent process accidents.

[0004] In existing technologies, camera imaging is used to capture the edges of wafers. Chinese Patent Publication No. CN119108317B proposes a wafer edge-finding method and apparatus. This method involves moving a chuck stage along one or more of the X, Y, and θ axes to compensate for center deviations, during which the wafer and chuck stage separate. Then, the chuck stage is rotated around its center to compensate for angular deviations. This method has the following problems: 1. The separation of the wafer and chuck stage during center compensation leads to reduced positioning accuracy; 2. Two image acquisitions are performed, including acquiring images of the edge arc and edge notches, which is time-consuming; 3. Multiple positioning operations are required, specifically: separating the wafer and chuck stage for center compensation, followed by rotation compensation, resulting in too many actions and a long processing time.

[0005] Therefore, a wafer edge-finding and positioning method is needed to improve positioning efficiency and accuracy. Summary of the Invention

[0006] The purpose of this application is to provide a vision-based wafer edge location method, apparatus, and readable medium to address the aforementioned technical problems.

[0007] In a first aspect, the present invention provides a vision-based wafer edge-finding and positioning method, based on a wafer edge-finding and positioning system. The system includes a rotation and translation platform for placing the wafer to be positioned and an image acquisition device for acquiring edge images. The method includes the following steps:

[0008] The control rotation and translation platform drives the wafer to be positioned to rotate one revolution relative to the image acquisition device. Each time the wafer to be positioned rotates by a preset angle, the image acquisition device is triggered to acquire a frame of the edge image of the wafer to be positioned.

[0009] A mechanical coordinate system is constructed based on the wafers located in standard positions. An edge point search algorithm is used to extract edge points from all edge images. All edge points are transformed into the mechanical coordinate system, and a circle equation is fitted to determine the center of the circle to be located.

[0010] A gap matching algorithm is used to perform gap matching search on all edge images to obtain matching results, which include the gap image and the center of the gap to be located.

[0011] Set a first transition position, and the notch image of the wafer to be positioned located at the first transition position coincides with the first frame edge image. According to the frame number of the notch image and the preset angle, the center of the notch to be positioned is transformed to the mechanical coordinate system, and the rotation angle is calculated in the mechanical coordinate system based on the center of the circle to be positioned and the center of the notch to be positioned.

[0012] The rotation and translation platform is controlled to rotate and translate the wafer to be positioned according to the center of the circle to be positioned and the rotation angle, so as to adjust the wafer to be positioned to the standard position.

[0013] Preferably, a mechanical coordinate system is constructed based on the wafer located in a standard position. An edge point search algorithm is used to extract edge points from all edge images. All edge points are then transformed into the mechanical coordinate system, and a circle equation is fitted to determine the center of the circle to be located. Specifically, this includes:

[0014] A mechanical coordinate system is constructed with the center of the wafer in the standard position as the origin and the direction from the center of the wafer in the standard position to the center of the standard notch as the positive X-axis.

[0015] Edge points of each frame of edge image are extracted using an edge point finding algorithm along the vertical midline of each frame edge image. The edge point finding algorithm includes the Sobel algorithm or the Canny algorithm.

[0016] Obtain the image coordinates of each edge point, represented as ,in, and Let x and y represent the pixel x and y coordinates of the edge points in the i-th frame edge image, respectively.

[0017] Transform the image coordinates of all edge points to the machine coordinate system to obtain the machine coordinates of all edge points, as shown in the following formula:

[0018] ;

[0019] ;

[0020] in, This represents the x-coordinate of the edge point in the i-th frame edge image in the machine coordinate system. This represents the ordinate of the edge point in the i-th frame edge image in the machine coordinate system; i represents the frame number of the edge image. L1 represents the preset angle; L2 represents the radius of the wafer; L3 represents the distance between the edge point of the i-th frame edge image and the intersection of the vertical bisector of the edge image and the edge of the wafer at the standard position, as shown in the following formula:

[0021] ;

[0022] in, Indicates the image pixel height. Indicates pixel equivalent;

[0023] The random sampling consensus algorithm is used to remove outliers from all edge points in the machine coordinate system to obtain the fitted edge points;

[0024] The least squares method is used to fit the circle equation of the wafer to be positioned in the mechanical coordinate system based on the mechanical coordinates of all fitted edge points, and the mechanical coordinates of the center of the circle corresponding to the wafer to be positioned are determined based on the circle equation.

[0025] Preferably, a gap matching algorithm is used to perform gap matching searches on all edge images to obtain matching results. The matching results include the gap image and the center of the gap to be located, specifically including:

[0026] Create a gap template, perform gap matching search on each frame edge image based on the gap template, and mark the edge image as an undetermined image in response to determining that the edge image matches a gap;

[0027] Calculate the distance between the geometric center of the gap in each frame of the image to be determined and the vertical bisector of the image to be determined. Take the image to be determined with the smallest distance as the gap image and take the geometric center of the gap in the gap image as the center of the gap to be located.

[0028] Preferably, the center of the notch to be located is transformed into the machine coordinate system based on the frame number and preset angle of the notch image, and the rotation angle is calculated in the machine coordinate system based on the center of the circle to be located and the center of the notch to be located, specifically including:

[0029] Obtain the image coordinates of the center of the notch to be located, where the pixel x-coordinate of the center of the notch to be located is represented as... The pixel ordinate of the center of the notch to be located is represented as ;

[0030] The center of the notch to be positioned on the wafer to be positioned at the first transition position is taken as the center of the first transition notch. The parameters of the edge image acquired by the image acquisition device are obtained. The parameters of the edge image include the image pixel width, the image pixel height, and the pixel equivalent. The mechanical coordinates of the center of the first transition notch are calculated based on the wafer radius L1, the image coordinates of the center of the notch to be positioned, and the parameters of the edge image, as shown in the following formula:

[0031] ;

[0032] ;

[0033] in, This represents the x-coordinate of the center of the first transition gap in the machine coordinate system; This represents the ordinate of the center of the first transition gap in the machine coordinate system; Indicates the image pixel width;

[0034] The mechanical coordinates of the center of the first transition gap are calculated based on the mechanical coordinates of the center, the frame number of the gap image, and the preset angle, as shown in the following formula:

[0035] ;

[0036] ;

[0037] in, This represents the x-coordinate of the center of the notch to be located in the machine coordinate system. This represents the ordinate of the center of the notch to be located in the machine coordinate system;

[0038] The polar angle of the center of the notch to be positioned relative to the center of the circle to be positioned is calculated based on the mechanical coordinates of the center of the notch to be positioned and the mechanical coordinates of the center of the circle to be positioned. The polar angle is the rotation angle.

[0039] Preferably, the rotation and translation platform is controlled to rotate and translate the wafer to be positioned based on the center of the circle to be positioned and the rotation angle, so as to adjust the wafer to be positioned to the standard position, specifically including:

[0040] A second transition position is set, and the positional relationship between the wafer to be positioned at the second transition position and the wafer to be positioned satisfies the following: after the wafer to be positioned rotates by a certain angle with the origin of the mechanical coordinate system as the base point, it coincides with the wafer to be positioned at the second transition position, and the center of the wafer to be positioned at the second transition position is taken as the center of the second transition circle.

[0041] The mechanical coordinates of the center of the wafer to be positioned are calculated after rotation according to the rotation angle, and the mechanical coordinates of the second transition center are obtained. The horizontal and vertical coordinates of the second transition center in the mechanical coordinate system represent the horizontal translation component and the vertical translation component when the wafer to be positioned is adjusted, respectively.

[0042] The rotation and translation platform is controlled by the rotation angle, lateral translation component, and longitudinal translation component to adjust the wafer to be positioned to the standard position.

[0043] Preferably, after the wafer to be positioned is adjusted to the standard position, the following steps are also included:

[0044] The image acquisition device is triggered to acquire a frame of edge image of the wafer to be positioned at a standard location, thus obtaining the verification image;

[0045] The notch template is used to perform notch matching and search on the verification image to obtain the center of the verification notch and the image coordinates of the center of the verification notch.

[0046] Obtain the notch image of the wafer located at the standard position, and obtain the image coordinates of the standard notch center. Calculate the deviation value between the verification notch center and the standard notch center based on the image coordinates of the verification notch center and the image coordinates of the standard notch center.

[0047] Determine if the deviation value is less than the set value. If it is, the wafer to be positioned is positioned successfully; otherwise, the wafer to be positioned is positioned abnormally and an alarm command is triggered.

[0048] Secondly, the present invention provides a vision-based wafer edge-finding and positioning device, based on a wafer edge-finding and positioning system. The system includes a rotation and translation platform for placing the wafer to be positioned and an image acquisition device for acquiring edge images. The device includes:

[0049] The image acquisition module is configured to control the rotating translation platform to drive the wafer to be positioned to rotate one revolution relative to the image acquisition device. Each time the wafer to be positioned rotates by a preset angle, the image acquisition device is triggered to acquire a frame of edge image of the wafer to be positioned.

[0050] The wafer center determination module is configured to construct a mechanical coordinate system based on the wafer located in a standard position, use an edge point search algorithm to extract edge points of all edge images, transform all edge points to the mechanical coordinate system, and perform circle equation fitting to determine the center of the circle to be located.

[0051] The gap center determination module is configured to use a gap matching algorithm to perform gap matching search on all edge images and obtain matching results, which include the gap image and the gap center to be located.

[0052] The rotation angle determination module is configured to set a first transition position, where the notch image of the wafer to be positioned at the first transition position coincides with the first frame edge image. Based on the frame number of the notch image and the preset angle, the center of the notch to be positioned is transformed to the mechanical coordinate system, and the rotation angle is calculated in the mechanical coordinate system based on the center of the circle to be positioned and the center of the notch to be positioned.

[0053] The adjustment module is configured to control the rotation and translation platform to perform rotation and translation operations on the wafer to be positioned based on the center of the circle to be positioned and the rotation angle, so as to adjust the wafer to be positioned to the standard position.

[0054] Thirdly, the present invention provides an electronic device including one or more processors; and a memory for storing one or more programs, which, when executed by one or more processors, cause the one or more processors to implement the method as described in any implementation of the first aspect.

[0055] Fourthly, the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method as described in any of the implementations of the first aspect.

[0056] Fifthly, the present invention provides a computer program product, including a computer program that, when executed by a processor, implements the method as described in any of the implementations in the first aspect.

[0057] Compared with the prior art, the present invention has the following beneficial effects:

[0058] (1) The vision-based wafer edge-finding and positioning method proposed in this application acquires an edge image of the wafer to be positioned once to determine the position of the center of the wafer to be positioned and the center of the notch to be positioned. The wafer to be positioned is adjusted to the standard position in one adjustment, which simplifies the edge-finding and positioning process, solves the problem of multiple positioning and poor accuracy in the prior art, and improves the positioning efficiency and positioning accuracy.

[0059] (2) The vision-based wafer edge location method proposed in this application determines the center of the notch to be located by image processing and sets the first transition position to solve the mechanical coordinates of the notch to be located, which simplifies the process of determining the center of the notch to be located, improves the positioning efficiency, and has strong anti-interference and high positioning accuracy.

[0060] (3) The vision-based wafer edge positioning method proposed in this application also sets up an adjustment result verification, collects the edge image of the wafer to be positioned after it is adjusted to the standard position, performs deviation analysis on the adjustment result, ensures the reliability of the adjustment result, and avoids subsequent process accidents. Attached Figure Description

[0061] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0062] Figure 1 This is a schematic flowchart illustrating a vision-based wafer edge location method according to an embodiment of this application.

[0063] Figure 2 This is a side view of a wafer edge-finding and positioning system according to an embodiment of this application;

[0064] Figure 3 This is a top view of a wafer edge-finding and positioning system according to an embodiment of this application;

[0065] Figure 4 The edge image is an embodiment of this application;

[0066] Figure 5 This is a schematic diagram of the edge image of frame 19 in the mechanical coordinate system, representing an embodiment of this application.

[0067] Figure 6 This is a schematic diagram of the edge image in the machine coordinate system during the coordinate transformation process of an embodiment of this application;

[0068] Figure 7 The images to be determined are for embodiments of this application, wherein a is the first image to be determined, b is the second image to be determined, and c is the third image to be determined;

[0069] Figure 8 This is a notch image of an embodiment of this application;

[0070] Figure 9 This is a schematic diagram of the wafer to be positioned in the mechanical coordinate system, representing an embodiment of this application.

[0071] Figure 10 This is a schematic diagram of the wafer to be positioned at the first transition position in the mechanical coordinate system, according to an embodiment of this application.

[0072] Figure 11 This is a schematic diagram of the wafer to be positioned at the second transition position in the mechanical coordinate system, according to an embodiment of this application.

[0073] Figure 12 This is a schematic diagram of a vision-based wafer edge-finding and positioning device according to an embodiment of this application;

[0074] Figure 13 This is a schematic diagram of the hardware structure of an electronic device provided in an embodiment of the present invention.

[0075] Figure descriptions: 11. Rotation and translation platform; 12. Image acquisition device; 13. Light source module; 14. Wafer to be positioned; 141. Notch to be positioned; 15. Wafer in standard position; 151. Standard notch; 16. First transition wafer; 17. Second transition wafer; 171. Second transition notch; 21. Edge image; 211. Vertical bisector; 212. Edge point; 22. Notch image. Detailed Implementation

[0076] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0077] Figure 1 This application illustrates a vision-based wafer edge-finding and positioning method based on an embodiment of the present application. The method is based on a wafer edge-finding and positioning system, which includes a rotation and translation platform for placing the wafer to be positioned and an image acquisition device for acquiring edge images. The method includes the following steps:

[0078] S1 controls the rotation and translation platform to drive the wafer to be positioned to rotate one revolution relative to the image acquisition device. Each time the wafer to be positioned rotates by a preset angle, the image acquisition device is triggered to acquire a frame of the edge image of the wafer to be positioned.

[0079] For details, please refer to Figure 2 and Figure 3This application proposes a wafer edge-finding and positioning system, including a rotation and translation platform 11, an image acquisition device 12, and a light source module 13. The image acquisition device 12 uses an industrial camera, and the light source module 13 uses a surface light source. The light source module 13 is installed below the image acquisition device 12. The wafer to be positioned, 14, is installed on the rotation and translation platform 11, positioned between the image acquisition device 12 and the light source module 13. In this embodiment, the rotation and translation platform 11 is controlled to rotate the wafer to be positioned counterclockwise at a constant speed, synchronously triggering the image acquisition device 12 to acquire edge images 21. All acquired edge images 21 are stored sequentially. For example, if the constant speed is one revolution every 3 seconds, and the rotation and translation platform 11 triggers image acquisition once every 3° rotation of the wafer to be positioned, then the rotation and translation platform 11 will acquire 120 frames of edge images 21 for one revolution of the wafer to be positioned.

[0080] S2. Construct a mechanical coordinate system based on the wafer located in the standard position, use an edge point search algorithm to extract edge points of all edge images, transform all edge points to the mechanical coordinate system, and perform circle equation fitting to determine the center of the circle to be located.

[0081] In a specific embodiment, a mechanical coordinate system is constructed based on the wafer located at a standard position. An edge point search algorithm is used to extract edge points from all edge images. All edge points are then transformed to the mechanical coordinate system, and a circle equation is fitted to determine the center of the circle to be located. Specifically, this includes:

[0082] A mechanical coordinate system is constructed with the center of the wafer in the standard position as the origin and the direction from the center of the wafer in the standard position to the center of the standard notch as the positive X-axis.

[0083] Edge points of each frame of edge image are extracted using an edge point finding algorithm along the vertical midline of each frame edge image. The edge point finding algorithm includes the Sobel algorithm or the Canny algorithm.

[0084] Obtain the image coordinates of each edge point, represented as ,in, and Let x and y represent the pixel x and y coordinates of the edge points in the i-th frame edge image, respectively.

[0085] Transform the image coordinates of all edge points to the machine coordinate system to obtain the machine coordinates of all edge points, as shown in the following formula:

[0086] ;

[0087] ;

[0088] in, This represents the x-coordinate of the edge point in the i-th frame edge image in the machine coordinate system. This represents the ordinate of the edge point in the i-th frame edge image in the machine coordinate system; i represents the frame number of the edge image. L1 represents the preset angle; L2 represents the radius of the wafer; L3 represents the distance between the edge point of the i-th frame edge image and the intersection of the vertical bisector of the edge image and the edge of the wafer at the standard position, as shown in the following formula:

[0089] ;

[0090] in, Indicates the image pixel height. Indicates pixel equivalent;

[0091] The random sampling consensus algorithm is used to remove outliers from all edge points in the machine coordinate system to obtain the fitted edge points;

[0092] The least squares method is used to fit the circle equation of the wafer to be positioned in the mechanical coordinate system based on the mechanical coordinates of all fitted edge points, and the mechanical coordinates of the center of the circle corresponding to the wafer to be positioned are determined based on the circle equation.

[0093] For details, please refer to Figure 3 , Figure 4 and Figure 5 The vertical midpoint 211 of each frame edge image 21 acquired by the image acquisition device 12 intersects with the wafer 15 located at the standard position at the midpoint of the edge image 21, and the pixel height of the edge image 21 is obtained through pre-calibration. Image pixel height and pixel equivalent . refer to Figure 4 and Figure 5 In each frame of edge image 21, an edge point finding algorithm is used to extract edge points on the vertical midline 211, and the image coordinates of each edge point 212 are obtained. The edge point finding algorithm includes the Sobel algorithm or the Canny algorithm. Compared to the method of obtaining contour point coordinates using sensors, this application improves the positioning accuracy of edge points 212 by extracting edge points 212 through image processing edge point finding algorithms. In the embodiments of this application, if an edge point 212 cannot be found in an edge image 21, the search stops, it is determined that the deviation of the wafer 14 to be positioned is too large, and an alarm command is triggered.

[0094] Since the edge points 212 of each edge image 21 are not associated with each other, coordinate unification is required. In the embodiments of this application, a mechanical coordinate system is constructed with the center C1 of the wafer 15 located in the standard position as the origin and the direction from the center C1 of the wafer 15 located in the standard position to the center A1 of the standard notch as the positive X-axis. Figure 5 As shown, all edge points 212 of edge image 21 are represented. In the machine coordinate system, the image coordinates of edge points 212 are used to determine the edge points. The radius L1 of the wafer, the preset angle angle, and the frame order i of the edge image 21 are used to perform coordinate transformation on the edge points to obtain the mechanical coordinates of edge point 212. (Reference) Figure 3 and Figure 6 In the embodiments of this application, during edge image acquisition, the wafer 14 to be positioned rotates counterclockwise while the image acquisition device 12 remains stationary. During coordinate transformation, for ease of calculation, it is assumed that the wafer 14 to be positioned remains stationary while the image acquisition device 12 rotates clockwise to take the picture. Figure 6 As shown. For example, see reference. Figure 5 At the 19th edge image acquisition point, the edge image acquired by the image acquisition device 12 is the 19th frame edge image 21. The mechanical coordinates of the edge point 212 are calculated according to step S2.

[0095] An edge point search algorithm is used to extract edge points 212 from all edge images 21. All edge points 212 are then transformed to a mechanical coordinate system. A random sampling consensus algorithm is used to remove outliers, such as abnormal edge points 212 caused by burrs or edge chips, from all edge points 212, resulting in fitted edge points. The least squares method is then used to fit a circle equation to all fitted edge points to determine the center C of the circle to be located.

[0096] Traditional methods use sensors to acquire contour point coordinates, and the positioning accuracy is entirely determined by the sensor. Furthermore, sensors have laser emitters and receivers, and precise alignment of these ends during equipment assembly significantly impacts measurement accuracy. Specifically, existing integrated displacement sensors are bulky and unsuitable for use, while split displacement sensors are difficult to install and calibrate, making it hard to ensure consistency across different devices. Moreover, the cost of sensors is higher than that of image acquisition equipment. This application proposes a vision-based wafer edge-finding and positioning method that uses image processing to extract the edges of the wafer 14 to be positioned, improving the extraction accuracy of edge points 212 and thus improving the contour fitting accuracy of the wafer 14. It also exhibits strong anti-interference capabilities, solving the problems of poor wafer edge contour fitting accuracy and high cost in existing sensor-based wafer edge-finding and positioning methods.

[0097] S3. Use the notch matching algorithm to perform notch matching search on all edge images to obtain a matching result, where the matching result includes a notch image and the center of the notch to be located.

[0098] In a specific embodiment, use the notch matching algorithm to perform notch matching search on all edge images to obtain a matching result, where the matching result includes a notch image and the center of the notch to be located. Specifically, it includes:

[0099] Create a notch template, and perform notch matching search on each frame of edge image according to the notch template. In response to determining that the edge image matches a notch, mark the edge image as a pending image.

[0100] Calculate the distance between the geometric center of the notch of each frame of pending image and the vertical bisector of the pending image, and use the pending image corresponding to the smallest distance as the notch image, and use the geometric center of the notch of the notch image as the center of the notch to be located.

[0101] Specifically, refer to Figures 7 to 9 , pre-create a notch template, and use the notch matching algorithm to perform notch matching search on all edge images 21 according to the notch template to obtain three pending images shown in part (a) of Figure 7 , part (b) of Figure 7 , and part (c) of Figure 7 . The notches on the three pending images are all the notches 141 to be located of the wafer 14 to be located. Calculate the distances between the geometric centers of the notches of the three pending images and their vertical bisectors 211 respectively, and obtain the distance d1 between the geometric center of the notch of the first pending image and its vertical bisector 211, the distance d2 between the geometric center of the notch of the second pending image and its vertical bisector 211, and the distance d3 between the geometric center of the notch of the third pending image and its vertical bisector 211. In the embodiment of the present application, d2 < d3 < d1. Therefore, use the second pending image as the notch image 22, and use the geometric center of the notch of the notch image 22 as the center of the notch to be located A.

[0102] S4. Set a first transition position, where the notch image of the wafer to be located at the first transition position coincides with the first frame of edge image. Convert the center of the notch to be located to the mechanical coordinate system according to the frame number where the notch image is located and the preset angle, and calculate the rotation angle in the mechanical coordinate system according to the center of the circle to be located and the center of the notch to be located.

[0103] In a specific embodiment, convert the center of the notch to be located to the mechanical coordinate system according to the frame number where the notch image is located and the preset angle, and calculate the rotation angle in the mechanical coordinate system according to the center of the circle to be located and the center of the notch to be located. Specifically, it includes:

[0104] Obtain the image coordinates of the center of the notch to be located, where the pixel x-coordinate of the center of the notch to be located is represented as... The pixel ordinate of the center of the notch to be located is represented as ;

[0105] The center of the notch to be positioned on the wafer to be positioned at the first transition position is taken as the center of the first transition notch. The parameters of the edge image acquired by the image acquisition device are obtained. The parameters of the edge image include the image pixel width, the image pixel height, and the pixel equivalent. The mechanical coordinates of the center of the first transition notch are calculated based on the wafer radius L1, the image coordinates of the center of the notch to be positioned, and the parameters of the edge image, as shown in the following formula:

[0106] ;

[0107] ;

[0108] in, This represents the x-coordinate of the center of the first transition gap in the machine coordinate system; This represents the ordinate of the center of the first transition gap in the machine coordinate system; Indicates the image pixel width;

[0109] The mechanical coordinates of the center of the first transition gap are calculated based on the mechanical coordinates of the center, the frame number of the gap image, and the preset angle, as shown in the following formula:

[0110] ;

[0111] ;

[0112] in, This represents the x-coordinate of the center of the notch to be located in the machine coordinate system. This represents the ordinate of the center of the notch to be located in the machine coordinate system;

[0113] The polar angle of the center of the notch to be positioned relative to the center of the circle to be positioned is calculated based on the mechanical coordinates of the center of the notch to be positioned and the mechanical coordinates of the center of the circle to be positioned. The polar angle is the rotation angle.

[0114] For details, please refer to Figure 9 According to step S3, the edge image of frame 49 is determined to be the notch image 22. (Reference) Figure 10The first transition position is set as follows: The wafer to be positioned 14 is rotated counterclockwise around the origin of the mechanical coordinate system, so that the notch image 22 of the wafer to be positioned 14 coincides with the first frame edge image 21, resulting in the wafer to be positioned at the first transition position. This wafer is designated as the first transition wafer 16, the center of the notch to be positioned on the wafer to be positioned at the first transition position is designated as the first transition center C2, and the center of the notch to be positioned on the wafer to be positioned at the first transition position is designated as the first transition notch center A2. Since the notch image 22 of the wafer to be positioned 14 is the 49th frame edge image (i=49), and the preset angle for triggering edge image acquisition is 3°, the positional relationship between the wafer to be positioned 14 and the first transition wafer 16 satisfies the following: the wafer to be positioned 14 is rotated counterclockwise by 147° around the origin of the mechanical coordinate system to obtain the first transition wafer 16. (Reference) Figure 9 and Figure 10 According to step S4, first calculate the mechanical coordinates of the center A2 of the first transition notch; then, according to the positional relationship between the wafer 14 to be positioned and the first transition wafer 16, rotate the mechanical coordinates of the center A2 of the first transition notch clockwise by 147° to obtain the mechanical coordinates of the center A of the notch to be positioned; finally, calculate the polar angle Q_notch of the center A of the notch to be positioned relative to the center C of the circle to be positioned based on the mechanical coordinates of the center A of the notch to be positioned and the mechanical coordinates of the center C of the circle to be positioned. The polar angle Q_notch is the rotation angle.

[0115] This application proposes a vision-based wafer edge-finding and positioning method. This method determines the center A of the notch to be located using image processing and sets a first transition position to solve for the mechanical coordinates of the notch center A. This simplifies the process of determining the notch center A and avoids the efficiency problems caused by additional sensors or manual markings to assist notch positioning, or by repeatedly acquiring wafer edge images for notch positioning. It also avoids the accuracy problems associated with sensor-based wafer edge-finding and positioning methods, as well as notch positioning after center-based positioning. This not only improves positioning efficiency but also provides strong anti-interference capabilities and high positioning accuracy. Furthermore, the method combining image processing and setting a first transition position to determine the notch center in this application can be adapted to wafers with different notch types.

[0116] S5, based on the center of the circle to be positioned and the rotation angle, control the rotation and translation platform to perform rotation and translation operations on the wafer to be positioned, so as to adjust the wafer to be positioned to the standard position.

[0117] In a specific embodiment, the rotation and translation platform is controlled to perform rotation and translation operations on the wafer to be positioned based on the center of the circle to be positioned and the rotation angle, so as to adjust the wafer to be positioned to a standard position, specifically including:

[0118] A second transition position is set, and the positional relationship between the wafer to be positioned at the second transition position and the wafer to be positioned satisfies the following: after the wafer to be positioned rotates by a certain angle with the origin of the mechanical coordinate system as the base point, it coincides with the wafer to be positioned at the second transition position, and the center of the wafer to be positioned at the second transition position is taken as the center of the second transition circle.

[0119] The mechanical coordinates of the center of the wafer to be positioned are calculated after rotation according to the rotation angle, and the mechanical coordinates of the second transition center are obtained. The horizontal and vertical coordinates of the second transition center in the mechanical coordinate system represent the horizontal translation component and the vertical translation component when the wafer to be positioned is adjusted, respectively.

[0120] The rotation and translation platform is controlled by the rotation angle, lateral translation component, and longitudinal translation component to adjust the wafer to be positioned to the standard position.

[0121] For details, please refer to Figures 9 to 11 The wafer to be positioned at the second transition position is designated as the second transition wafer 17. The center of the wafer to be positioned at the second transition position is designated as the second transition center C3. The center of the notch to be positioned at the second transition position is designated as the second transition notch center A3. The notch to be positioned at the second transition position is designated as the second transition notch 171. The second transition notch 171 has no angular deviation from the standard notch 151 of the wafer 15 in the standard position. However, the center of the second transition center C3 does not coincide with the center C1 of the wafer 15 in the standard position. This is because the center C of the wafer 14 to be positioned is not on the rotation axis passing through the origin of the machine coordinate system. At this time, the second transition wafer 17 can be adjusted to the standard position only through a translation operation, so that the second transition center C3 is located at the origin of the machine coordinate system. Therefore, the translation component of adjusting the wafer 14 to the standard position can be calculated by calculating the machine coordinates of the second transition center C3. The mechanical coordinates of the center C to be positioned are calculated after rotation from the origin of the mechanical coordinate system by a rotation angle Q_notch, resulting in the mechanical coordinates of the second transition center C3. The horizontal and vertical coordinates of the second transition center C3 in the mechanical coordinate system represent the lateral and vertical translation components of the wafer 14 to be positioned during adjustment, respectively. Based on the rotation angle, the lateral translation component, and the vertical translation component, the rotation and translation platform 11 is controlled to adjust the wafer 14 to the standard position in a single adjustment.

[0122] In embodiments of this application, the lateral and longitudinal translation components can also be calculated based on the relationship between the center of the notch to be positioned (A), the center of the second transition notch (A3), and the center of the standard notch (A1) of the wafer 14 to be positioned. Specifically, the mechanical coordinates of the center of the notch to be positioned (A) are calculated by rotating the mechanical coordinates of the notch to be positioned (A) with the origin of the mechanical coordinate system as the base point according to the rotation angle Q_notch. The difference between the abscissa and ordinate of the center of the second transition notch (A3) and the center of the standard notch (A1) in the mechanical coordinate system are then calculated to obtain the lateral and longitudinal translation components. In a specific embodiment, if the mechanical coordinates of a known point on the wafer 14 to be positioned and the mechanical coordinates of the matching point on the wafer 15 located at the standard position corresponding to the known point are determined, the above method can also be used to calculate the lateral and longitudinal translation components based on the mechanical coordinates of the known point and the matching point.

[0123] The present application proposes a vision-based wafer edge-finding and positioning method. By acquiring an edge image 21 of the wafer 14 to be positioned once, the position of the center C of the wafer 14 to be positioned and the center A of the notch to be positioned can be determined. The rotation angle and translation components are calculated. The wafer 14 to be positioned is adjusted to the standard position in one adjustment, which simplifies the edge-finding and positioning process and improves the positioning efficiency and positioning accuracy.

[0124] In a specific embodiment, after the wafer to be positioned is adjusted to the standard position, the process further includes:

[0125] The image acquisition device is triggered to acquire a frame of edge image of the wafer to be positioned at a standard location, thus obtaining the verification image;

[0126] The notch template is used to perform notch matching and search on the verification image to obtain the center of the verification notch and the image coordinates of the center of the verification notch.

[0127] Obtain the notch image of the wafer located at the standard position, and obtain the image coordinates of the standard notch center. Calculate the deviation value between the verification notch center and the standard notch center based on the image coordinates of the verification notch center and the image coordinates of the standard notch center.

[0128] Determine if the deviation value is less than the set value. If it is, the wafer to be positioned is positioned successfully; otherwise, the wafer to be positioned is positioned abnormally and an alarm command is triggered.

[0129] Specifically, alarm commands include outputting error codes or relocation instructions to remind operators to handle abnormal situations in a timely manner.

[0130] Compared with existing technologies, the vision-based wafer edge-finding and positioning method proposed in this application can simultaneously realize wafer center coordinate positioning, notch angle positioning, and positioning result verification. It is especially suitable for the initial positioning of wafers before processes such as photolithography, etching, marking, quality inspection, and wafer transfer. Specifically, the vision-based wafer edge-finding and positioning method proposed in this application achieves simultaneous positioning of the center C and rotation angle of the wafer to be positioned by acquiring edge images 21 during a single rotation of the wafer 14 to be positioned. Only one adjustment positioning is required, resulting in higher positioning efficiency and accuracy. It avoids redundancy of multiple sensors and eliminates the need for multiple positioning to separately determine the wafer center and notch center, simplifying the edge-finding and positioning process. The edge points 212 of the multi-frame edge images 21 are screened using the Random Sampling Consensus Algorithm (RANSAC algorithm), which has strong anti-interference ability and effectively suppresses noise interference from defects such as burrs and edge chipping. An industrial camera and surface light source are used to replace the high-precision laser sensor, reducing hardware costs. The adjustment result verification is set up by acquiring edge images of the wafer 14 to be positioned after adjustment to the standard position and performing deviation analysis on the adjustment results to ensure the reliability of the adjustment results and avoid process accidents caused by sensor failure or noise.

[0131] The steps S1-S5 above do not necessarily represent the order of the steps, but are represented by step symbols. The order of the steps can be adjusted.

[0132] Further reference Figure 12 As an implementation of the methods shown in the above figures, this application provides an embodiment of a vision-based wafer edge-finding and positioning device, which is similar to... Figure 1 Corresponding to the method embodiments shown, this device can be specifically applied to various electronic devices.

[0133] This application provides a vision-based wafer edge-finding and positioning device, based on a wafer edge-finding and positioning system. The system includes a rotation and translation platform for placing the wafer to be positioned and an image acquisition device for acquiring edge images. The device includes:

[0134] Image acquisition module 1 is configured to control the rotation and translation platform to drive the wafer to be positioned to rotate one revolution relative to the image acquisition device. Each time the wafer to be positioned rotates by a preset angle, the image acquisition device is triggered to acquire a frame of edge image of the wafer to be positioned.

[0135] The wafer center determination module 2 is configured to construct a mechanical coordinate system based on the wafer located in a standard position, use an edge point search algorithm to extract edge points of all edge images, transform all edge points to the mechanical coordinate system, and perform circle equation fitting to determine the center of the circle to be located.

[0136] The gap center determination module 3 is configured to use a gap matching algorithm to perform gap matching search on all edge images and obtain matching results, which include the gap image and the gap center to be located.

[0137] The rotation angle determination module 4 is configured to set a first transition position, where the notch image of the wafer to be positioned at the first transition position coincides with the first frame edge image. Based on the frame number of the notch image and the preset angle, the center of the notch to be positioned is transformed to the mechanical coordinate system, and the rotation angle is calculated in the mechanical coordinate system based on the center of the circle to be positioned and the center of the notch to be positioned.

[0138] Adjustment module 5 is configured to control the rotation and translation platform to perform rotation and translation operations on the wafer to be positioned based on the center of the circle to be positioned and the rotation angle, so as to adjust the wafer to be positioned to the standard position.

[0139] Figure 13 This is a schematic diagram of the hardware structure of an electronic device provided in an embodiment of the present invention. For example... Figure 13 As shown, the electronic device in this embodiment includes a processor 1301 and a memory 1302; wherein the memory 1302 is used to store computer execution instructions; and the processor 1301 is used to execute the computer execution instructions stored in the memory to implement the various steps performed by the electronic device in the above embodiment. For details, please refer to the relevant descriptions in the foregoing method embodiments.

[0140] Alternatively, the memory 1302 can be either standalone or integrated with the processor 1301.

[0141] When the memory 1302 is set up independently, the electronic device also includes a bus 1303 for connecting the memory 1302 and the processor 1301.

[0142] This invention also provides a computer storage medium storing computer execution instructions, which, when executed by the processor 1301, implement the above method.

[0143] This invention also provides a computer program product, including a computer program that, when executed by a processor 1301, implements the above-described method.

[0144] In the embodiments provided by this invention, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative; for instance, the division of modules is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple modules may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, devices, or modules, and may be electrical, mechanical, or other forms.

[0145] The modules described as separate components may or may not be physically separate. The components shown as modules may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to implement the solution of this embodiment according to actual needs.

[0146] Furthermore, the functional modules in the various embodiments of the present invention can be integrated into one processing unit, or each module can exist physically separately, or two or more modules can be integrated into one unit. The unit composed of the above modules can be implemented in hardware or in the form of hardware plus software functional units.

[0147] The integrated modules described above, implemented as software functional modules, can be stored in a computer-readable storage medium. These software functional modules, stored in a storage medium, include several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) or processor 1301 to execute certain steps of the methods of the various embodiments of this application.

[0148] It should be understood that the processor 1301 described above can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), etc. The general-purpose processor can be a microprocessor, or the processor 1301 can be any conventional processor 1301. The steps of the method disclosed in this invention can be directly manifested as the hardware processor 1301 executing the steps, or as a combination of hardware and software modules within the processor 1301 executing the steps.

[0149] The memory 1302 may include high-speed RAM memory, and may also include non-volatile memory NVM, such as at least one disk storage, and may also be a USB flash drive, portable hard drive, read-only memory, disk or optical disc, etc.

[0150] Bus 1303 can be an Industry Standard Architecture (ISA), a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Bus 1303 can be divided into address bus, data bus, control bus, etc. For ease of illustration, the bus 1303 in the accompanying drawings of this application is not limited to only one bus 1303 or one type of bus 1303.

[0151] The aforementioned storage medium can be implemented from any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The storage medium can be any available medium accessible to general-purpose or special-purpose computers.

[0152] An exemplary storage medium is coupled to processor 1301, enabling processor 1301 to read information from and write information to the storage medium. Alternatively, the storage medium can be an integral part of processor 1301. Processor 1301 and storage medium can reside in an application-specific integrated circuit (ASIC). Alternatively, processor 1301 and storage medium can exist as discrete components in an electronic device or host device.

[0153] Those skilled in the art will understand that all or part of the steps of the above-described method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments; and the aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0154] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A vision-based wafer edge-finding positioning method, characterized by, A wafer edge-finding and positioning system includes a rotation and translation platform for placing the wafer to be positioned and an image acquisition device for acquiring edge images. The method includes the following steps: The rotating translation platform is controlled to drive the wafer to be positioned to rotate one revolution relative to the image acquisition device. Each time the wafer to be positioned rotates by a preset angle, the image acquisition device is triggered to acquire a frame of the edge image of the wafer to be positioned. A mechanical coordinate system is constructed based on the wafers located in standard positions. An edge point search algorithm is used to extract the edge points of all the edge images. All the edge points are transformed into the mechanical coordinate system, and a circle equation is fitted to determine the center of the circle to be located. A gap matching algorithm is used to perform gap matching search on all the edge images to obtain matching results, which include the gap image and the center of the gap to be located. A first transition position is set, and the notch image of the wafer to be positioned located at the first transition position coincides with the edge image of the first frame. The center of the notch to be positioned is transformed into the mechanical coordinate system according to the frame number of the notch image and the preset angle, and the rotation angle is calculated in the mechanical coordinate system according to the center of the circle to be positioned and the center of the notch to be positioned. The rotation and translation platform is controlled to rotate and translate the wafer to be positioned according to the center of the circle to be positioned and the rotation angle, so as to adjust the wafer to be positioned to the standard position.

2. The vision-based wafer edge-finding positioning method of claim 1, wherein, The process of constructing a mechanical coordinate system based on a wafer located at a standard position, extracting edge points from all edge images using an edge point search algorithm, transforming all edge points to the mechanical coordinate system, and performing circle equation fitting to determine the center of the circle to be located specifically includes: A mechanical coordinate system is constructed with the center of the wafer in the standard position as the origin and the direction from the center of the wafer in the standard position to the center of the standard notch as the positive X-axis. Edge points of each frame of the edge image are extracted using an edge point finding algorithm along the vertical midline of each frame of the edge image. The edge point finding algorithm includes the Sobel algorithm or the Canny algorithm. obtaining image coordinates of each of the edge points, denoted as wherein, and denote the pixel horizontal coordinate and the pixel vertical coordinate of the edge point of the edge image of the i-th frame, respectively. Transform the image coordinates of all edge points to the machine coordinate system to obtain the machine coordinates of all edge points, as shown in the following formula: ； ； wherein, Xi represents the horizontal coordinate of the edge point of the edge image of the i-th frame in the mechanical coordinate system, Yi represents the vertical coordinate of the edge point of the edge image of the i-th frame in the mechanical coordinate system; i represents the frame number of the edge image, θ represents a preset angle; L1 represents the radius of the wafer; L2 represents the distance between the edge point of the edge image of the i-th frame and the intersection of the vertical middle line of the edge image and the edge of the wafer located at the standard position, as shown in the following formula: ； in, Indicates the image pixel height. Indicates pixel equivalent; The random sampling consensus algorithm is used to remove outliers from all the edge points in the machine coordinate system to obtain the fitted edge points; The least squares method is used to fit the circle equation of the wafer to be positioned in the mechanical coordinate system based on the mechanical coordinates of all the fitted edge points, and the mechanical coordinates of the center of the circle corresponding to the wafer to be positioned are determined based on the circle equation.

3. The vision-based wafer edge location method according to claim 2, characterized in that, The notch matching algorithm is used to perform notch matching on all the edge images to obtain matching results. The matching results include the notch image and the center of the notch to be located, specifically including: Create a gap template, perform gap matching search on each frame of the edge image according to the gap template, and in response to determining that the edge image matches a gap, mark the edge image as an image to be determined; Calculate the distance between the geometric center of the gap in each frame of the image to be determined and the vertical bisector of the image to be determined. Take the image to be determined with the smallest distance as the gap image and take the geometric center of the gap in the gap image as the center of the gap to be located.

4. The vision-based wafer edge location method according to claim 3, characterized in that, The step of transforming the center of the notch to be located to the machine coordinate system based on the frame number of the notch image and the preset angle, and calculating the rotation angle in the machine coordinate system based on the center of the circle to be located and the center of the notch to be located, specifically includes: Obtain the image coordinates of the center of the notch to be located, wherein the pixel x-coordinate of the center of the notch to be located is represented as... The pixel ordinate of the center of the notch to be located is represented as ; Using the center of the notch to be positioned on the wafer located at the first transition position as the center of the first transition notch, the parameters of the edge image acquired by the image acquisition device are obtained. The parameters of the edge image include the image pixel width, the image pixel height, and the pixel equivalent. The mechanical coordinates of the center of the first transition notch are calculated based on the radius L1 of the wafer, the image coordinates of the center of the notch to be positioned, and the parameters of the edge image, as shown in the following formula: ； ； in, This represents the x-coordinate of the center of the first transition gap in the machine coordinate system; This represents the ordinate of the center of the first transition gap in the machine coordinate system; Indicates the image pixel width; The mechanical coordinates of the center of the first transition gap are calculated based on the mechanical coordinates of the center, the frame number of the gap image, and the preset angle, as shown in the following formula: ； ； in, This represents the x-coordinate of the center of the notch to be located in the machine coordinate system. This represents the ordinate of the center of the notch to be located in the machine coordinate system; The polar angle of the center of the notch to be positioned relative to the center of the circle to be positioned is calculated based on the mechanical coordinates of the center of the notch to be positioned and the mechanical coordinates of the center of the circle to be positioned. The polar angle is a rotation angle.

5. The vision-based wafer edge location method according to claim 4, characterized in that, The step of controlling the rotation and translation platform to perform rotation and translation operations on the wafer to be positioned based on the center of the circle to be positioned and the rotation angle, so as to adjust the wafer to be positioned to the standard position, specifically includes: A second transition position is set, and the positional relationship between the wafer to be positioned at the second transition position and the wafer to be positioned satisfies the following: after the wafer to be positioned rotates by the rotation angle with the origin of the mechanical coordinate system as the base point, it coincides with the wafer to be positioned at the second transition position, and the center of the wafer to be positioned at the second transition position is taken as the center of the second transition circle. The mechanical coordinates of the center of the circle to be positioned after rotation according to the rotation angle are calculated to obtain the mechanical coordinates of the second transition center. The horizontal and vertical coordinates of the second transition center in the mechanical coordinate system represent the lateral translation component and the vertical translation component when the wafer to be positioned is adjusted, respectively. The rotation and translation platform is controlled according to the rotation angle, lateral translation component, and longitudinal translation component to adjust the wafer to be positioned to the standard position.

6. The vision-based wafer edge location method according to claim 3, characterized in that, After the wafer to be positioned is adjusted to the standard position, the following steps are also included: The image acquisition device is triggered to acquire a frame of the edge image of the wafer to be positioned at a standard position, thus obtaining a verification image; The verification image is matched and searched according to the notch template to obtain the center of the verification notch, and the image coordinates of the center of the verification notch are obtained. Obtain an image of the notch on the wafer at a standard position, and obtain the image coordinates of the standard notch center. Calculate the deviation between the verification notch center and the standard notch center based on the image coordinates of the verification notch center and the image coordinates of the standard notch center. Determine whether the deviation value is less than the set value. If it is, the wafer to be positioned is positioned successfully; otherwise, the wafer to be positioned is positioned abnormally and an alarm command is triggered.

7. A vision-based wafer edge-finding and positioning device, characterized in that, A wafer edge-finding and positioning system is provided, the system comprising a rotation and translation platform for placing the wafer to be positioned and an image acquisition device for acquiring edge images, the device comprising: The image acquisition module is configured to control the rotation and translation platform to drive the wafer to be positioned to rotate one revolution relative to the image acquisition device. Each time the wafer to be positioned rotates by a preset angle, the image acquisition device is triggered to acquire one frame of the edge image of the wafer to be positioned. The wafer center determination module is configured to construct a mechanical coordinate system based on the wafer located in a standard position, extract edge points of all the edge images using an edge point search algorithm, transform all the edge points to the mechanical coordinate system, and perform circle equation fitting to determine the center of the circle to be located. The gap center determination module is configured to use a gap matching algorithm to perform gap matching search on all the edge images to obtain a matching result, the matching result including the gap image and the gap center to be located; The rotation angle determination module is configured to set a first transition position, wherein the notch image of the wafer to be positioned located at the first transition position coincides with the edge image of the first frame, and the center of the notch to be positioned is transformed to the mechanical coordinate system according to the frame number of the notch image and the preset angle, and the rotation angle is calculated in the mechanical coordinate system according to the center of the circle to be positioned and the center of the notch to be positioned. The adjustment module is configured to control the rotation and translation platform to perform rotation and translation operations on the wafer to be positioned based on the center of the circle to be positioned and the rotation angle, so as to adjust the wafer to be positioned to a standard position.

8. An electronic device, characterized in that, include: One or more processors; Memory, used to store one or more programs. When the one or more programs are executed by the one or more processors, the one or more processors implement the method as described in any one of claims 1-6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the method as described in any one of claims 1-6.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the method as described in any one of claims 1-6.

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