Collaborative positioning method, device, storage medium and wafer loading method

Abstract

The present application discloses a collaborative positioning method, device, storage medium and wafer loading method. The collaborative positioning method determines the first pixel coordinates of multiple grinding and polishing stations in the planetary wheel through a first positioning image captured by a first camera; determines the second pixel coordinates of multiple positioning stations in the wafer loading positioning buffer table through a second positioning image captured by a second camera; obtains the position mapping relationship between the camera coordinate systems of the first camera and the second camera; determines the alignment adjustment amount of the wafer positioning station based on the first pixel coordinate, the second pixel coordinate and the position mapping relationship; and adjusts the relative position relationship of the multiple positioning stations to be the same as the relative position relationship of the multiple grinding and polishing stations. Through the collaborative positioning method of the present application, it is possible to achieve synchronous alignment of multiple wafers located in the wafer loading buffer module and the multiple grinding and polishing stations located in the planetary wheel in the wafer polishing equipment, thereby achieving one-time loading of multiple wafers and improving the grinding and polishing efficiency of the wafers.

Description

Technical Field

[0001] The present application relates to the field of semiconductor processing equipment, and in particular to a collaborative positioning method, device, storage medium and wafer loading method. Background Art

[0002] Double-sided polishing is a crucial step in the wafer processing process during wafer production. Prior to polishing and grinding, the wafers are positioned and cached in a wafer buffer. During processing, a loading robot removes the wafers from the wafer buffer and places them into the wafer slots in the planetary wheel for processing.

[0003] In the prior art, automated wafer loading and caching for wafer polishing and grinding involves a robotic arm picking up wafers one at a time from a loading cassette, placing multiple wafers onto a buffering table. Another robotic arm then intermittently places these buffered wafers onto a planetary wheel positioned through wafer slots. However, this caching method allows the robotic arm to load only one wafer at a time, resulting in low loading efficiency.

[0004] With respect to the problem of low wafer loading efficiency in wafer polishing and grinding in related technologies, no effective solution has been proposed. Summary of the Invention

[0005] In order to solve the above technical problems, the present application provides a collaborative positioning method for wafer loading to solve the problem of low efficiency of wafer loading.

[0006] In a first aspect, a collaborative positioning method for wafer loading is provided, comprising: obtaining a first positioning image captured by a first camera, and determining first pixel coordinates of a plurality of grinding and polishing stations in a planetary wheel based on the first positioning image; obtaining a second positioning image captured by a second camera, and determining second pixel coordinates of a plurality of positioning stations in a wafer loading positioning buffer table based on the second positioning image; obtaining a position mapping relationship between a camera coordinate system of the first camera and a camera coordinate system of the second camera; determining an alignment adjustment amount of the wafer positioning station based on the first pixel coordinates, the second pixel coordinates and the position mapping relationship; and adjusting the relative position relationship of the plurality of positioning stations to be the same as the relative position relationship of the plurality of grinding and polishing stations based on the alignment adjustment amount.

[0007] In one embodiment, obtaining the position mapping relationship between the camera coordinate system of the first camera and the camera coordinate system of the second camera includes: obtaining a first mapping relationship between the camera pixels of the first camera and the world coordinates of the upper and lower film motion module loaded with the second camera; obtaining a second mapping relationship between the camera pixels of the second camera and the world coordinates of the upper and lower film motion module loaded with the second camera; and determining the position mapping relationship between the camera coordinate system of the first camera and the camera coordinate system of the second camera based on the first mapping relationship and the second mapping relationship.

[0008] In one embodiment, obtaining the first mapping relationship between the camera pixels of the first camera and the world coordinates of the upper and lower piece motion module equipped with the second camera includes: obtaining the position of the upper and lower piece motion module and capturing the first image of the calibration plate through the stationary first camera during the process of the upper and lower piece motion module driving the calibration plate to move; determining a first calibration matrix according to the position of the upper and lower piece motion module and the first image; and determining the first mapping relationship based on the first calibration matrix.

[0009] In one embodiment, the second mapping relationship between the camera pixels of the second camera and the world coordinates of the upper and lower film motion module equipped with the second camera is obtained, which includes: obtaining the position of the upper and lower film motion module and collecting the second image of the stationary calibration plate through the second camera during the process of the upper and lower film motion module driving the second camera to move; determining a second calibration matrix according to the position of the upper and lower film motion module and the second image; and determining the calibration plate based on the second calibration matrix. The second mapping relationship.

[0010] In one embodiment, determining the alignment adjustment amount of the positioning station based on the first pixel coordinate, the second pixel coordinate and the position mapping relationship includes: determining the first relative position of the plurality of grinding and polishing stations in the planetary wheel in the world coordinate system according to the first pixel coordinate and the position mapping relationship; determining the second relative position of the plurality of positioning stations on the wafer cache platform in the world coordinate system according to the second pixel coordinate and the position mapping relationship; and comparing the first relative position and the second relative position to determine the alignment adjustment amount.

[0011] In one embodiment, adjusting the relative position relationship of the plurality of positioning stations to be the same as the relative position relationship of the plurality of grinding and polishing stations based on the alignment adjustment amount includes: determining the alignment adjustment amount of the positioning station in the first horizontal direction and the alignment adjustment amount in the second horizontal direction based on the alignment adjustment amount, the first horizontal direction being perpendicular to the second horizontal direction; adjusting the relative position relationship of the plurality of positioning stations to be the same as the relative position relationship of the plurality of grinding and polishing stations based on the alignment adjustment amount in the first horizontal direction and the alignment adjustment amount in the second horizontal direction.

[0012] In one embodiment, determining the first pixel coordinates of multiple grinding and polishing stations in the planetary wheel based on the first positioning image also includes: obtaining the teaching connection line angle and the teaching midpoint position of the teaching planetary wheel, the teaching connection line angle is the angle between the connection line of the two positioning holes on the teaching planetary wheel and the first horizontal direction, and the teaching midpoint position is the position of the midpoint of the connection line of the two positioning holes on the teaching planetary wheel; obtaining the relative distance between the center of each grinding and polishing station in the teaching planetary wheel and the midpoint of the connection line; storing the teaching connection line angle, teaching midpoint position and multiple relative distances as a teaching formula; obtaining the measured angle information and measured midpoint position of the connection line of the two positioning holes on the planetary wheel to be inspected based on the first positioning image; calculating the first pixel coordinates of any grinding and polishing station in the planetary wheel to be inspected based on the measured angle information, the measured midpoint position and the teaching formula.

[0013] In the second aspect, a collaborative positioning device for wafer loading is provided, the device comprising: a first acquisition unit for acquiring a first positioning image captured by a first camera, and determining first pixel coordinates of multiple grinding and polishing stations in a planetary wheel based on the first positioning image; a second acquisition unit for acquiring a second positioning image captured by a second camera, and determining second pixel coordinates of multiple positioning stations in a wafer loading positioning buffer table based on the second positioning image; a third acquisition unit for acquiring a position mapping relationship between a camera coordinate system of the first camera and a camera coordinate system of the second camera; a calculation unit for determining an alignment adjustment amount of the wafer positioning station based on the first pixel coordinate, the second pixel coordinate and the position mapping relationship; an alignment unit for adjusting the relative position relationship of the multiple positioning stations to be the same as the relative position relationship of the multiple grinding and polishing stations based on the alignment adjustment amount.

[0014] In a third aspect, a storage medium is provided, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the collaborative positioning method as described in any embodiment of the first aspect when executed.

[0015] In a fourth aspect, a wafer loading method is provided, which includes: a detection and unloading motion module equipped with a first camera to capture a first positioning image and send it to a collaborative positioning device; an upper and lower wafer motion module takes out a wafer to be processed from a loading box and places it on a wafer loading buffer module; the upper and lower wafer motion module captures a second positioning image of the wafer loading buffer module and sends it to the collaborative positioning device; the collaborative positioning device is used to execute the collaborative positioning method as described in any one of the embodiments of the first aspect above, so that the relative position of each positioning station in the wafer loading buffer module is consistent with the relative position relationship of each grinding and polishing station in the planetary wheel; the upper and lower wafer motion module absorbs the wafers in a plurality of the positioning stations and transfers them to the corresponding grinding and polishing stations of the planetary wheel.

[0016] The collaborative positioning method provided by the present application determines the deviation between the relative position of each grinding and polishing station on the planetary wheel and the relative position of the positioning station by obtaining the first positioning image of the planetary wheel, the second positioning image of the positioning station, and the position mapping relationship of the camera coordinate system of the first camera and the second camera, and obtains the alignment adjustment amount for aligning the positioning station with the grinding and polishing station in the world coordinate system. Based on the alignment adjustment amount, the relative position relationship of the multiple positioning stations is adjusted to be the same as the relative position relationship of the multiple grinding and polishing stations. The collaborative positioning method provided by the present application solves the problem of aligning each wafer with the grinding and polishing station when loading multiple wafers at a time, provides a positioning basis for the one-time adsorption of the multi-wafer loading scheme, and thus solves the problem of low loading efficiency of single-wafer loading in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematic diagram of the structure of a wafer polishing and grinding device according to an embodiment of the present application;

[0018] Figure 2 is a structural diagram of an upper slice cache module according to an embodiment of the present application;

[0019] Figure 3 is a flowchart of a collaborative positioning method according to an embodiment of the present application;

[0020] Figure 4 This is a schematic diagram of the teaching points of the planetary wheel according to an embodiment of the present application;

[0021] Figure 5 is a schematic structural diagram of a collaborative positioning device according to an embodiment of the present application;

[0022] Figure 6 1 is a flow chart of a wafer loading method according to an embodiment of the present application;

[0023] Explanation of the accompanying figures: 10, polishing and grinding machine; 20, detection and unloading motion module; 30, loading and unloading cache module; 40, loading and unloading motion module; 11, planetary wheel; 111, grinding and polishing station; 31, loading and unloading positioning cache table; 32, cache motion device; 311, positioning station; 312, adjustment platform. DETAILED DESCRIPTION

[0024] To make the above-mentioned objects, features, and advantages of the present invention more readily apparent, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. The following description sets forth numerous specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0025] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0026] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0027] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0028] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0029] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only implementation methods.

[0030] Wafer polishing and grinding is a key process in semiconductor manufacturing, primarily used to flatten the wafer surface and ensure the accuracy and yield of subsequent processes such as photolithography and thin film deposition. Previously, automated wafer loading and unloading for polishing and grinding primarily relied on robotic arms to pick up and place individual wafers. This method is inefficient, and achieving simultaneous loading and unloading of multiple wafers requires aligning each wafer with the polishing station, a crucial requirement for improving wafer loading and unloading efficiency.

[0031] The present application provides a wafer polishing and grinding device, such as Figure 1 and Figure 2 As shown, it includes a polishing grinder 10, a detection and unloading motion module 20, a wafer loading buffer module 30, and an upper and lower wafer motion module 40. The polishing grinder 10 includes a plurality of planetary wheels 11, and each planetary wheel 11 has a plurality of grinding and polishing stations 111. The detection and unloading motion module 20 is used to detect the relative position relationship of the plurality of grinding and polishing stations 111 and generate a control signal. The wafer loading buffer module 30 includes a wafer positioning buffer table 31 and a buffer motion device 32. The wafer positioning buffer table 31 includes a positioning station 311 and an adjustment platform 312. The buffer motion device 32 can transfer the wafer in the wafer positioning buffer table 31 to the positioning station 311. The adjustment platform 312 is used to adjust the wafer in the positioning station 311 in response to the control signal; the upper and lower wafer motion module 40 is used to move the wafer to the grinding and polishing station 111.

[0032] In this embodiment, a collaborative positioning method for wafer placement is provided, which is applied to the wafer polishing and grinding equipment described in the previous embodiment, such as Figure 3As shown, the method includes:

[0033] Step S301 : obtaining a first positioning image captured by a first camera, and determining first pixel coordinates of a plurality of grinding and polishing stations 111 in the planetary wheel 11 based on the first positioning image.

[0034] Specifically, the first camera is mounted on the detection and unloading motion module 20 of the polishing and grinding equipment to capture images of the planetary wheel. The detection and unloading motion module 20 includes a mounting assembly and a motion assembly. The mounting assembly is used to mount the first camera. Preferably, the mounting assembly utilizes a non-fixed connection to facilitate adjustment of the first camera's camera position. The motion assembly is used to drive the first camera to move between different imaging positions of the planetary wheel 11. Generally, the polishing and grinding machine 10 includes multiple planetary wheels 11. Due to manufacturing processes and other factors, the positions of the grinding and polishing stations 111 within each planetary wheel 11 vary to some extent. Therefore, in this embodiment, the first camera captures an image of the planetary wheel at a imaging position. After the acquisition is completed, the camera is driven by the motion assembly to move to the next imaging position to capture the next planetary wheel image. In another embodiment, the first camera can also capture images of multiple planetary wheels in a single image. The first positioning image is the planetary wheel image. The grinding and polishing stations 111 are wafer aperture slots located on the planetary wheel 11. The pixel coordinate system is a two-dimensional plane composed of pixels and is commonly used to represent the position and size of an image. The first pixel coordinates of the plurality of grinding and polishing stations 111 in the planetary wheel 11 are determined based on the first positioning image. That is, the positions of the plurality of grinding and polishing stations 111 in the image are determined based on the planetary wheel image. For ease of calculation, the first pixel coordinate of each grinding and polishing station 111 can be represented by the center point of the grinding and polishing station 111.

[0035] Step S302 : obtaining a second positioning image captured by a second camera, and determining second pixel coordinates of a plurality of positioning stations 311 in the positioning buffer based on the second positioning image.

[0036] Specifically, the second camera is mounted on the wafer loading and unloading motion module 40 of the wafer polishing and grinding equipment. The second camera photographs the wafer loading buffer module 30 of the wafer polishing and grinding equipment, captures an image of the positioning station 311 of the wafer loading positioning buffer stage 31, and obtains a second positioning image. The second pixel coordinates of the plurality of positioning stations 311 are obtained in the pixel coordinate system of the second positioning image.

[0037] Step S303: Acquire a position mapping relationship between the camera coordinate system of the first camera and the camera coordinate system of the second camera.

[0038] Specifically, the camera coordinate system is a three-dimensional rectangular coordinate system established with the camera's focal center as its origin and the optical axis as its Z-axis. The optical axis is perpendicular to the drawing plane. Obtaining the position mapping relationship between the camera coordinate system of the first camera and the camera coordinate system of the second camera enables coordinate conversion between the first and second cameras.

[0039] Step S304 : determining an alignment adjustment amount of the positioning station 311 based on the first pixel coordinate, the second pixel coordinate, and the position mapping relationship.

[0040] Specifically, based on the first pixel coordinates, the second pixel coordinates, and the position mapping relationship, the relative positional relationship between the grinding and polishing stations 111 and the relative positional relationship between the positioning stations 311 in the same coordinate system can be obtained. By comparing the relative positional relationship between the grinding and polishing stations 111 with the relative positional relationship between the positioning stations 311, the alignment adjustment amount of the wafer positioning station 311 can be obtained.

[0041] In step S305 , the relative position relationship of the plurality of positioning stations 311 is adjusted to be the same as the relative position relationship of the plurality of grinding and polishing stations 111 based on the alignment adjustment amount.

[0042] Specifically, after determining the alignment adjustment amount, a control signal is generated and sent to the wafer loading positioning buffer stage 31. The adjustment platform 312 of the wafer loading positioning buffer stage 31 adjusts the relative position relationship of the positioning stations 311 in response to the control signal, so that the relative position relationship of each positioning station 311 is the same as the relative position relationship of each grinding and polishing station 111. Furthermore, at this time, the relative position relationship of the wafers located in each positioning station 311 is the same as the relative position relationship of each grinding and polishing station 111 in the planetary wheel 11. The wafer loading and unloading motion module 40 can then absorb all the wafers located in each positioning station 311 at one time and transfer them to the grinding and polishing station 111.

[0043] The collaborative positioning method of this embodiment uses a first camera to collect image data of the grinding and polishing station 111 on the planetary wheel 11; uses a second camera to collect image data of the positioning station 311 on the positioning buffer table; obtains the position mapping relationship between the camera coordinate system of the first camera and the camera coordinate system of the second camera, and converts the image data of the grinding and polishing station 111 and the image data of the positioning station 311 to the same coordinate system based on the position mapping relationship. At this time, based on the same coordinate system, the relative position relationship between each grinding and polishing station 111 is used as a reference, and the relative position relationship between each positioning station 311 is compared to determine the alignment adjustment amount of the adjustment platform 312; then, based on the alignment adjustment amount, the wafer position is made to correspond to the position of the grinding and polishing station 111 in the planetary wheel 11, and finally, all wafers are transferred at one time through the upper and lower wafer movement module 40. The collaborative positioning method of this embodiment realizes the precise alignment of multiple wafers with multiple grinding and polishing stations 111, completes the alignment conditions for one-time multi-wafer loading, and can significantly improve the wafer loading efficiency compared with the single-wafer loading solution in the prior art.

[0044] In one embodiment, obtaining the position mapping relationship between the camera coordinate system of the first camera and the camera coordinate system of the second camera includes: obtaining a first mapping relationship between the camera pixels of the first camera and the world coordinates of the upper and lower film motion module 40 loaded with the second camera; obtaining a second mapping relationship between the camera pixels of the second camera and the world coordinates of the upper and lower film motion module 40 loaded with the second camera; and determining the position mapping relationship between the camera coordinate system of the first camera and the camera coordinate system of the second camera based on the first mapping relationship and the second mapping relationship.

[0045] Specifically, when the wafer polishing and grinding equipment is in working condition, the first camera is installed in the detection and unloading motion module 20; the second camera is installed in the upper and lower film motion module 40. The wafer polishing and grinding equipment can determine the position of the first camera based on the world coordinates of the detection and unloading motion module 20; and can determine the position of the second camera based on the world coordinates of the upper and lower film motion module 40. In order to determine the position deviation between the grinding and polishing station 111 in the downstream star wheel 11 and the positioning station 311 in the upper film buffer module 30 in the world coordinate system, the camera coordinate system of the first camera and the camera coordinate system of the second camera need to be aligned. Therefore, in this embodiment, by pre-installing the first camera and the second camera in the upper and lower film motion module 40 respectively to calibrate the mapping relationship, the first mapping relationship and the second mapping relationship are obtained respectively, and the position mapping relationship between the camera coordinate system of the first camera and the camera coordinate system of the second camera is determined based on the first mapping relationship and the second mapping relationship.

[0046] Among them, the pixel coordinates (P1x, R1y) of the first camera can obtain the position (R2x, R2y) under the calibration posture of the upper and lower piece motion module 40 through the nine-point calibration relationship matrix HomMath2D_2, thereby establishing a first mapping relationship between the camera pixels of the first camera and the world coordinates of the upper and lower piece motion module 40; the position (R2x, R2y) under the calibration posture of the upper and lower piece motion module 40 is obtained through the inverse relationship of the nine-point calibration relationship matrix HomMath2D_3 to obtain the second camera pixel coordinates (P2x, P2y). At this point, the position mapping relationship between the camera coordinates of the first camera and the camera coordinate system of the second camera is determined.

[0047] In one embodiment, obtaining a first mapping relationship between camera pixels of a first camera and world coordinates of an upper and lower piece motion module 40 equipped with a second camera includes: obtaining the position of the upper and lower piece motion module 40 and a first image of the calibration plate captured by a stationary first camera during the process of the upper and lower piece motion module 40 driving the calibration plate to move; determining a first calibration matrix according to the position of the upper and lower piece motion module 40 and the first image; and determining a first mapping relationship based on the first calibration matrix.

[0048] Specifically, the first and second cameras, as well as the loading and unloading motion module 40, used in the photography process, are pre-calibrated using a calibration plate and a nine-point calibration method. The calibration process collects the current nine-point coordinates of the camera and robot as input, and uses the nine-point calibration method to output matrix-related parameters. The first calibration matrix is ​​denoted as HomMath2D_2, and the calibration process is as follows: the first camera remains stationary, while the loading and unloading motion module 40 moves with the calibration plate.

[0049] In one embodiment, obtaining a second mapping relationship between pixels of the second camera and the world coordinates of the upper and lower piece motion module 40 equipped with the second camera includes: obtaining the position of the upper and lower piece motion module 40 and capturing a second image of a stationary calibration plate through the second camera during the process of the upper and lower piece motion module 40 driving the second camera to move; determining a second calibration matrix according to the position of the upper and lower piece motion module 40 and the second image; and determining a second mapping relationship based on the second calibration matrix.

[0050] Specifically, the calibration process in this embodiment collects the current nine-point coordinates of the camera and robot as input, and outputs matrix-related parameters through a nine-point calibration method. The first calibration matrix is ​​denoted as HomMath2D_3, and the calibration process is as follows: the calibration plate is stationary, and the upper and lower plate motion module 40 moves with the calibration plate.

[0051] In one embodiment, determining the alignment adjustment amount of the positioning station 311 based on the first pixel coordinate, the second pixel coordinate and the position mapping relationship includes: determining the first relative position of the multiple grinding and polishing stations 111 in the planetary wheel 11 in the world coordinate system according to the first pixel coordinate and the position mapping relationship; determining the second relative position of the multiple positioning stations 311 on the upper wafer positioning buffer table 31 in the world coordinate system according to the inverted second pixel coordinate and the position mapping relationship; comparing the first relative position and the second relative position to determine the alignment adjustment amount.

[0052] Specifically, the first camera is mounted on the material-cutting motion module 20 for detection, and the second camera is mounted on the upper and lower film motion module 40. Therefore, the world coordinates of the first camera and the world coordinates of the second camera are determined by the world coordinates of the material-cutting motion module 20 and the upper and lower film motion module 40. The first coordinate system is also used for the adjustment of the positioning station 311. Therefore, to calculate the alignment adjustment amount, it is also necessary to establish a position mapping relationship between the camera pixels of the first camera and the world coordinates of the material-cutting motion module 20 for detection, as well as a position mapping relationship between the first camera coordinate system and the world coordinates of the adjustment platform 312 on the upper film positioning buffer table 31. Ultimately, a coordinate system is realized between the material-cutting motion module 20, the first camera, the second camera, the upper and lower film motion module 40, and the upper film positioning buffer table 31, so as to determine the alignment adjustment amount of the upper film positioning buffer table 31 based on the planetary wheel image captured by the first camera and the positioning station 311 image captured by the second camera.

[0053] The first camera is mounted on the material detection and unloading motion module 20, so a mapping relationship must be established between the first camera's pixel coordinates and the world coordinates of the detection and unloading motion module 20. The first camera's pixel points (P1x, P1y) are used to calculate the world coordinates of the detection and unloading motion module 20 using the nine-point calibration matrix HomMath2D_1. The HomMath2D_1 calibration process involves maintaining a stationary calibration plate while the detection and unloading motion module 20 moves with the first camera. The matrix parameters are then determined using a nine-point calibration method. When the material removal detection motion module 20 moves, in order to unify the pixel coordinate system before and after the movement of the first camera, the first camera coordinates before movement (R1x, R1y) are subtracted from the current (after movement) robot coordinates (R1x1, R1y1), that is, (R1x-R1x1, R1y-R1y1). Through the HomMath2D_1 inverse relationship matrix operation, the pixel coordinate position (P1x1, P1y1) of the first camera after the material removal detection motion module 20 moves is obtained, thereby establishing the coordinate position relationship between the camera pixels of the first camera and the material removal detection motion module 20.

[0054] The pixel coordinates (P2x, P2y) of the second camera can be converted into the world coordinates (R3x, R3y) in the coordinate system of the upper film buffer module 30 through the nine-point calibration relationship matrix HomMath2D_4. The HomMath2D_4 matrix can be calibrated by keeping the second camera stationary and moving the calibration plate with the upper and lower film motion module 40. Thus, by establishing the coordinate position relationship between the pixels of the first camera and the pixels of the unloading motion module 20, and the coordinate position relationship between the pixels of the first camera and the upper and lower film motion module 40, the position mapping relationship between the camera coordinate systems of the first camera and the second camera can be obtained. Then, through the mapping relationship between the pixels of the second camera and the upper film buffer module 30, the mapping relationship between the camera coordinate system of the first camera and the world coordinates of the positioning station 311 on the upper film buffer module 30 can be obtained.

[0055] During collaborative visual alignment, the relative position information of the grinding and polishing station 111 on the planetary wheel 11 is obtained by taking photos with the first camera and sent to the control system. The control system converts the information into motion control instructions for the adjustment platform 312 in the upper chip cache module 30, and drives the X, Y motion actuators of the adjustment platform 312 to move, thereby achieving the same relative position data between the positioning stations 311 of the upper chip cache module 30 and the grinding and polishing stations 111 of the planetary wheel 11.

[0056] In one embodiment, adjusting the relative position relationship of multiple positioning stations 311 to the same relative position relationship as multiple grinding and polishing stations 111 based on the alignment adjustment amount includes: determining the alignment adjustment amount of the positioning station 311 in the first horizontal direction and the alignment adjustment amount of the second horizontal direction based on the alignment adjustment amount, the first horizontal direction being perpendicular to the second horizontal direction; adjusting the relative position relationship of the multiple positioning stations 311 to the relative position relationship with the multiple grinding and polishing stations 111 based on the alignment adjustment amount in the first horizontal direction and the alignment adjustment amount in the second horizontal direction.

[0057] In one embodiment, determining the first pixel coordinates of multiple grinding and polishing stations in the planetary wheel based on the first positioning image also includes: obtaining the teaching connection line angle and the teaching midpoint position of the teaching planetary wheel, the teaching connection line angle is the angle between the connection line of the two positioning holes on the teaching planetary wheel and the first horizontal direction, and the teaching midpoint position is the position of the midpoint of the connection line of the two positioning holes on the teaching planetary wheel; obtaining the relative distance between the center of each grinding and polishing station in the teaching planetary wheel and the midpoint of the connection line; storing the teaching connection line angle, the teaching midpoint position and multiple relative distances as a teaching formula; obtaining the measured angle information and the measured midpoint position of the connection line of the two positioning holes on the planetary wheel to be inspected based on the first positioning image; and calculating the first pixel coordinates of any grinding and polishing station in the planetary wheel to be inspected based on the measured angle information, the measured midpoint position and the teaching formula.

[0058] Specifically, under ideal circumstances, when the polishing and grinding equipment provides sufficient shooting space and working distance for the first camera installed on the blanking detection motion module, the first camera can directly obtain the relative position of the grinding and polishing station 111 of the planetary wheel 11 before each wafer loading, that is, the field of view of one photo can cover the entire picture of at least one grinding and polishing station 111 in the planetary wheel 11, thereby determining the center position of the grinding and polishing station 111, and the aforementioned multi-machine vision collaborative dynamic positioning method can be used to guide the movement of the adjustment platform 312, thereby accurately realizing the multi-wafer loading task at one time.

[0059] When the shooting space and working distance provided by the polishing and grinding equipment to the first camera are insufficient, that is, the field of view of the first camera cannot cover the entire view of one polishing station 111 at a time, it is necessary to determine the positional relationship between the characteristic positioning hole (i.e., the Mark point) in the planetary wheel 11 and the center of each polishing station 111 through the teaching process, such as Figure 4 As shown, and stored in the form of a recipe, before loading the wafer, the first camera captures the positioning hole features of the planetary wheel 11 to determine the corresponding recipe. The control system then controls the movement of the adjustment platform 312 based on the center position information of each grinding and polishing station 111 in the recipe, so that the loading and unloading motion module 40 can accurately place multiple wafers at a time. When the wafer polishing equipment updates the planetary wheel 11, the planetary wheel 11 must be re-taught to update the relative position relationship between the mark point on the planetary wheel 11 and the center of the wafer hole.

[0060] In one specific embodiment, a rapid teaching method for the grinding and polishing station 111 of the planetary wheel 11 is provided, and the teaching method includes:

[0061] Step S501, calculating the angle of the line connecting the two positioning holes Mark1 and Mark2 on the planetary wheel 11 and the position of the midpoint P;

[0062] Step S502, calculate the center point Ci of the i-th wafer Circlei in the planetary wheel 11, i=1,2...N; conventional polishing equipment N=3 or 4; when N=3, the schematic diagram of the teaching point parameters of the planetary wheel 11 is as follows Figure 4 As shown;

[0063] Step S503, calculating and saving the distance Di from the midpoint P to the center Ci of the i-th grinding and polishing station 111;

[0064] In step S504 , the corresponding relationship between the Mark midpoint P, the angle of the line connecting the two points, and D1 , D2 . . . DN is saved in a formula format. The formula has a one-to-one corresponding relationship with the planetary wheel 11 .

[0065] In this embodiment, a collaborative positioning device for wafer placement is also provided. Figure 5 As shown, the device includes:

[0066] A first acquisition unit 51 is configured to acquire a first positioning image captured by a first camera, and determine first pixel coordinates of a plurality of grinding and polishing stations 111 in the planetary wheel 11 based on the first positioning image;

[0067] A second acquiring unit 52 is configured to acquire a second positioning image captured by a second camera, and determine second pixel coordinates of a plurality of positioning stations 311 in the loading positioning buffer 31 based on the second positioning image;

[0068] A third acquiring unit 53 is configured to acquire a position mapping relationship between a camera coordinate system of the first camera and a camera coordinate system of the second camera;

[0069] A calculation unit 54 is configured to determine an alignment adjustment amount of the wafer positioning station 311 based on the first pixel coordinate, the second pixel coordinate, and the position mapping relationship;

[0070] The alignment unit 55 is used to adjust the relative position relationship of the plurality of positioning stations 311 to be the same as the relative position relationship of the plurality of grinding and polishing stations 111 based on the alignment adjustment amount.

[0071] The third acquisition unit 53 is also used to obtain a first mapping relationship between the camera pixels of the first camera and the world coordinates of the upper and lower film motion module 40 loaded with the second camera; obtain a second mapping relationship between the camera pixels of the second camera and the world coordinates of the upper and lower film motion module 40 loaded with the second camera; and determine the position mapping relationship between the camera coordinate system of the first camera and the camera coordinate system of the second camera based on the first mapping relationship and the second mapping relationship.

[0072] In one embodiment, obtaining a first mapping relationship between camera pixels of a first camera and world coordinates of an upper and lower piece motion module 40 equipped with a second camera includes: obtaining the position of the upper and lower piece motion module 40 and capturing a first image of the calibration plate through a stationary first camera while the upper and lower piece motion module 40 drives the calibration plate to move; determining a first calibration matrix according to the position of the upper and lower piece motion module 40 and the first image; and determining a first mapping relationship based on the first calibration matrix.

[0073] In one embodiment, obtaining a second mapping relationship between camera pixels of the second camera and the world coordinates of the upper and lower film motion module 40 equipped with the second camera includes: obtaining the position of the upper and lower film motion module 40 and capturing a second image of a stationary calibration plate through the second camera during the process of the upper and lower film motion module 40 driving the second camera to move; determining a second calibration matrix based on the position of the upper and lower film motion module 40 and the second image; and determining a second calibration matrix based on the second calibration matrix. Second mapping Tie.

[0074] The calculation unit 54 is also used to determine the first relative position of the multiple grinding and polishing stations 111 in the planetary wheel 11 in the world coordinate system based on the first pixel coordinate and position mapping relationship; determine the second relative position of the multiple positioning stations 311 on the upper piece positioning buffer table 31 in the world coordinate system based on the second pixel coordinate and position mapping relationship; compare the first relative position and the second relative position to determine the alignment adjustment amount.

[0075] The alignment unit 55 is also used to determine the alignment adjustment amount of the positioning station 311 in the first horizontal direction and the alignment adjustment amount in the second horizontal direction based on the alignment adjustment amount, where the first horizontal direction is perpendicular to the second horizontal direction; based on the alignment adjustment amount in the first horizontal direction and the alignment adjustment amount in the second horizontal direction, the relative position relationship of the multiple positioning stations 311 is adjusted to be the same as the relative position relationship of the multiple grinding and polishing stations 111.

[0076] The first acquisition unit 51 is also used to obtain the teaching connection line angle and the teaching midpoint position of the teaching planet wheel, the teaching connection line angle is the angle between the connection line of the two positioning holes on the teaching planet wheel and the first horizontal direction, and the teaching midpoint position is the position of the midpoint of the connection line of the two positioning holes on the teaching planet wheel; obtain the relative distance between the center of each grinding and polishing station in the teaching planet wheel and the midpoint of the connection line; store the teaching connection line angle, the teaching midpoint position and multiple relative distances as a teaching formula; obtain the measured angle information and the measured midpoint position of the connection line of the two positioning holes on the planet wheel to be inspected based on the first positioning image; calculate the first pixel coordinates of any grinding and polishing station in the planet wheel to be inspected based on the measured angle information, the measured midpoint position and the teaching formula.

[0077] The present application also provides a storage medium, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the collaborative positioning method described in any of the above embodiments when executed.

[0078] This application also provides a wafer loading method, such as Figure 6 As shown, the wafer loading method includes:

[0079] Step S601: The blanking motion detection module 20 is equipped with a first camera to capture a first positioning image and send it to the collaborative positioning device;

[0080] Step S602: the wafer loading and unloading movement module 40 takes out the wafer to be processed from the loading box and places it in the wafer loading buffer module 30;

[0081] Step S603: the upper and lower slice motion module 40 collects the second positioning image of the upper slice buffer module 30 and sends it to the collaborative positioning device;

[0082] Step S604: The collaborative positioning device is configured to execute the collaborative positioning method described in any one of the embodiments of the first aspect, so that the relative positions of the positioning stations 311 in the upper wafer buffer module 30 are consistent with the relative positions of the grinding and polishing stations 111 in the planetary wheel 11;

[0083] In step S605 , the wafer loading and unloading movement module 40 picks up the wafers in the plurality of positioning stations 311 and transfers them to the corresponding grinding and polishing stations 111 of the planetary wheel 11 .

[0084] The wafer loading method of this embodiment, based on achieving visual collaborative positioning, realizes that the loading and unloading movement module 40 adsorbs multiple wafers to the grinding and polishing station 111 at one time, which greatly improves the wafer loading efficiency compared with the single-wafer loading solution in the prior art.

[0085] In one specific embodiment, a method for automatic caching, positioning, and loading of wafers for polishing and grinding is provided. For example, a planetary wheel 11 has three wafer slots, and a polishing and grinding machine 10 can accommodate five planetary wheels 11 at the same time.

[0086] In step S701, the upper and lower wafer movement module 40 takes out wafers from the loading wafer box FOUP and places them in the upper wafer cache module 30. When the top layer of the upper wafer cache module 30 is filled with 3 wafers, the double-wafer cache movement device 32 and the single-wafer cache movement device 32 move to place the 3 wafers in the lower cache station until the upper wafer cache module 30 is filled with 15 wafers.

[0087] Step S702 , when receiving the loading instruction, the unloading motion module 20 equipped with the first camera moves to the position above the i-th (i=1, 2, 3, 4, 5) positioning hole mark 1 of the planetary wheel 11 of the polishing and grinding machine 10 to obtain the position information of mark 1;

[0088] Step S703 , detecting and moving to the position above the positioning hole mark 2 of the planetary wheel 11 of the polishing and grinding machine 10 to obtain the position information of the mark 2 point.

[0089] Step S704, calculating the midpoint P of the line connecting the two points mark1 and mark2 and the angle of the line connecting the two points;

[0090] Step S705 , loading the teaching recipe, and inferring the relative position relationship of each grinding and polishing station 111 in the planetary wheel 11 based on the data calculated in step S704 .

[0091] Step S706: Using a multi-machine vision collaborative dynamic positioning method, the loading adjustment platform 312 is controlled to dynamically adjust the relative position of the positioning stations 311 so that it is consistent with the relative position data of the grinding and polishing station 111.

[0092] In step S707 , the wafer loading robot moves to the wafer loading buffer module 30 and simultaneously picks up three wafers and places them in the planetary wheel 11 of the polishing and grinding equipment; the wafer loading buffer module 30 takes out three wafers from the buffer station and places them in the wafer loading positioning station 311 .

[0093] Step S708 , repeating steps S702 to S707 until all the planetary wheels 11 of the polishing and grinding machine 10 are filled with wafers (i=5), and the wafer loading process is completed.

[0094] It can be understood that in this embodiment, one planetary wheel 11 has three wafer hole slots, and one polishing and grinding machine 10 can accommodate five planetary wheels 11 at the same time to illustrate the wafer loading process. In other specific embodiments, the number of planetary wheels 11 and grinding and polishing stations 111 can also be adjusted according to the processing technology.

[0095] The wafer loading method of this embodiment utilizes the positions of the positioning points on the grinding and polishing stations 311 and the planetary wheel 11 to store a teaching recipe, thereby improving the positioning accuracy of the grinding and polishing stations 111. By utilizing a visual collaborative positioning method, the center distances of the cached wafers in the positioning stations 311 can be dynamically adjusted based on the differences in the center distances of the grinding and polishing stations 111 within each planetary wheel 11, thereby improving positioning accuracy. Ultimately, based on the aligned positioning stations 311, the loading and unloading motion module 40 can simultaneously absorb multiple wafers onto the planetary wheel 11, significantly shortening the loading cycle.

[0096] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0097] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A collaborative positioning method for wafer placement, characterized in that: The method comprises: Acquire a first positioning image captured by a first camera, and determine first pixel coordinates of a plurality of grinding and polishing stations in the planetary wheel based on the first positioning image; Acquire a second positioning image captured by a second camera, and determine second pixel coordinates of a plurality of positioning stations in the wafer loading positioning buffer station based on the second positioning image; Acquire a position mapping relationship between a camera coordinate system of the first camera and a camera coordinate system of the second camera; determining an alignment adjustment amount of the positioning station based on the first pixel coordinate, the second pixel coordinate, and the position mapping relationship; Based on the alignment adjustment amount, the relative position relationship of the plurality of positioning stations is adjusted to be the same as the relative position relationship of the plurality of grinding and polishing stations.

2. The collaborative positioning method according to claim 1, characterized in that: The acquiring of a position mapping relationship between a camera coordinate system of the first camera and a camera coordinate system of the second camera includes: Obtaining a first mapping relationship between camera pixels of the first camera and world coordinates of an upper and lower film motion module equipped with the second camera; Obtaining a second mapping relationship between camera pixels of the second camera and world coordinates of an upper and lower film motion module equipped with the second camera; Based on the first mapping relationship and the second mapping relationship, a position mapping relationship between the camera coordinate system of the first camera and the camera coordinate system of the second camera is determined.

3. The collaborative positioning method according to claim 2, wherein: The obtaining of a first mapping relationship between camera pixels of the first camera and world coordinates of an upper and lower film motion module equipped with the second camera includes: In the process of the upper and lower sheet motion modules driving the calibration plate to move, obtaining the position of the upper and lower sheet motion modules and capturing a first image of the calibration plate by a stationary first camera; determining a first calibration matrix according to the positions of the upper and lower slice motion modules and the first image; The first mapping relationship is determined based on the first calibration matrix.

4. The collaborative positioning method according to claim 3, characterized in that: The obtaining of a second mapping relationship between camera pixels of the second camera and world coordinates of an upper and lower film motion module equipped with the second camera includes: In the process of the upper and lower sheet motion module driving the second camera to move, obtaining the position of the upper and lower sheet motion module and capturing a second image of the stationary calibration plate through the second camera; determining a second calibration matrix according to the positions of the upper and lower slice motion modules and the second image; The second mapping relationship is determined based on the second calibration matrix.

5. The collaborative positioning method according to claim 1, wherein: The determining of the alignment adjustment amount of the positioning station based on the first pixel coordinate, the second pixel coordinate, and the position mapping relationship includes: Determine first relative positions of the plurality of grinding and polishing stations in the planetary wheel in a world coordinate system according to the first pixel coordinates and the position mapping relationship; Determine the second relative positions of the plurality of positioning stations on the wafer buffer platform in the world coordinate system according to the second pixel coordinates and the position mapping relationship; The first relative position and the second relative position are compared to determine the alignment adjustment amount.

6. The collaborative positioning method according to claim 1, wherein: The step of adjusting the relative position relationship of the plurality of positioning stations to be the same as the relative position relationship of the plurality of grinding and polishing stations based on the alignment adjustment amount includes: determining an alignment adjustment amount of the positioning station in a first horizontal direction and an alignment adjustment amount in a second horizontal direction based on the alignment adjustment amount, the first horizontal direction being perpendicular to the second horizontal direction; The relative position relationship of the plurality of positioning stations is adjusted to be the same as the relative position relationship of the plurality of grinding and polishing stations based on the alignment adjustment amount in the first horizontal direction and the alignment adjustment amount in the second horizontal direction.

7. The collaborative positioning method according to claim 1, characterized in that: The determining of first pixel coordinates of a plurality of grinding and polishing stations in the planetary wheel based on the first positioning image further comprises: Obtaining a teaching connection line angle and a teaching midpoint position of the teaching planetary wheel, wherein the teaching connection line angle is the angle between a connection line of two positioning holes on the teaching planetary wheel and the first horizontal direction, and the teaching midpoint position is the position of the midpoint of the connection line of the two positioning holes on the teaching planetary wheel; Obtaining the relative distance between the center of each grinding and polishing station in the teaching planetary wheel and the midpoint of the connecting line; storing the teaching connection angle, the teaching midpoint position, and the plurality of relative distances as a teaching formula; Acquire the measured angle information and the measured midpoint position of the connecting line of the two positioning holes on the planetary gear to be inspected based on the first positioning image; The first pixel coordinate of any grinding and polishing station in the planetary wheel to be inspected is calculated based on the measured angle information, the measured midpoint position and the teaching formula.

8. A storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the collaborative positioning method according to any one of claims 1 to 7 when executed.

9. A wafer loading method, characterized in that: The wafer loading method comprises: The blanking motion detection module is equipped with a first camera to capture a first positioning image and send it to the collaborative positioning device; The loading and unloading motion module takes out the wafer to be processed from the loading box and places it in the loading buffer module; The upper and lower slice motion module collects the second positioning image of the upper slice buffer module and sends it to the collaborative positioning device; The collaborative positioning device is used to perform the collaborative positioning method according to any one of claims 1 to 7, so that the relative positions of the positioning stations in the upper wafer buffer module are consistent with the relative positions of the grinding and polishing stations in the planetary wheel; The upper and lower wafer movement modules absorb the wafers in the plurality of positioning stations and transfer them to the corresponding grinding and polishing stations of the planetary wheel.

10. A collaborative positioning device for wafer placement, characterized in that: The device comprises: a first acquisition unit, configured to acquire a first positioning image captured by a first camera, and determine first pixel coordinates of a plurality of grinding and polishing stations in the planetary wheel based on the first positioning image; a second acquiring unit, configured to acquire a second positioning image captured by a second camera, and determine second pixel coordinates of a plurality of positioning stations in the loading positioning buffer station based on the second positioning image; a third acquiring unit, configured to acquire a position mapping relationship between a camera coordinate system of the first camera and a camera coordinate system of the second camera; a calculation unit, configured to determine an alignment adjustment amount of the positioning station based on the first pixel coordinate, the second pixel coordinate, and the position mapping relationship; An alignment unit is used to adjust the relative position relationship of the plurality of positioning stations to be the same as the relative position relationship of the plurality of grinding and polishing stations based on the alignment adjustment amount.

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