Mechanical arm control method and device, front end module, electronic equipment and storage medium

Abstract

The application provides a mechanical hand control method and device, a front-end module, electronic equipment and a storage medium, and belongs to the technical field of semiconductor processing. The method comprises the following steps: acquiring a current running stage of a mechanical hand and a slot number of a current wafer to be taken; taking a preset height value corresponding to the slot number of the current wafer to be taken as a target height value, and controlling a lifting column to move up and down based on the target height value; if the current running stage is a wafer centering stage, acquiring an actual height value of the lifting column, calculating a height difference between the actual height value of the lifting column and the target height value, correcting a preset target position based on the height difference to obtain a corrected target position; and controlling a telescopic shaft of the mechanical hand to move based on the corrected target position, so that a chuck center of the mechanical hand is moved to a wafer center position. The application can improve the reliability of the front-end module for wafer processing.

Description

Technical Field

[0001] This application belongs to the field of semiconductor processing technology, and more specifically, relates to a robotic arm control method and device, a front-end module, an electronic device, and a storage medium. Background Technology

[0002] Semiconductors are core components of the modern electronics industry, and wafers are the core substrate for manufacturing semiconductor devices. In wafer fabrication, the front-end module (including the lifting column and the robotic arm) is the loading unit of the wafer fabrication equipment, primarily responsible for the transfer and supply of wafers. The robotic arm can be a two-axis robot (rotary axis + telescopic axis), with a suction cup at its end for picking up wafers. The lifting column supports the wafer cassette, and as wafers are picked up, the lifting column can adjust its height, working in conjunction with the robotic arm to pick up wafers one by one from each slot, orderly transporting the wafers to the processing station, completing the automated loading before processing.

[0003] In actual use, it was found that as the usage time of the front-end module increased, the frequency of the wafer falling off the suction cup increased, and the problem was not effectively solved even after replacing and cleaning the suction cup. Summary of the Invention

[0004] The purpose of this application is to provide a robotic arm control method and device, a front-end module, an electronic device, and a storage medium to improve the reliability of the front-end module used in wafer processing.

[0005] A first aspect of this application provides a front-end module for a wafer processing equipment. The front-end module includes a lifting column and a robotic arm, both communicatively connected to a controller. The lifting column carries a wafer cassette, which has multiple slots arranged sequentially along its height. The robotic arm has a suction cup at its end for adsorbing wafers. The robotic arm uses the suction cup to sequentially remove wafers from each slot and transfer them to a processing station. The method is executed by the controller and includes: Obtain the current operating stage of the robotic arm and the slot number of the wafer to be retrieved; The preset height value corresponding to the slot number of the current wafer to be retrieved is used as the target height value, and the lifting column is controlled to move up and down based on the target height value; If the current operating stage is the initial stage, then control the telescopic shaft of the robot to extend to the preset coupling starting point position; If the current operating stage is a coupled operating stage, then control the telescopic axis and the rotary axis of the robot to operate in conjunction according to the preset trajectory information; If the current operating stage is the wafer centering stage, then the actual height value of the lifting column is obtained, the height difference between the actual height value and the target height value of the lifting column is calculated, a first compensation amount of the suction cup center in the X-axis direction is determined based on the height difference and a preset first offset coefficient, a second compensation amount of the suction cup center in the Y-axis direction is determined based on the height difference and a preset second offset coefficient, and a preset target position is corrected based on the first compensation amount and the second compensation amount to obtain the corrected target position; the telescopic axis of the robot is controlled to move based on the corrected target position to move the suction cup center of the robot to the wafer center position; wherein, both the first offset coefficient and the second offset coefficient are linearly related to the installation tilt angle of the suction cup.

[0006] In a second aspect of this application, a controller is provided in a front-end module of a wafer processing equipment. The front-end module further includes a lifting column and a robotic arm, both communicatively connected to the controller. The lifting column carries a wafer cassette, which has multiple slots arranged sequentially along its height. The robotic arm has a suction cup at its end for adsorbing wafers. The robotic arm uses the suction cup to sequentially remove wafers from each slot and transfer them to the processing station. The device includes: The data acquisition unit is used to acquire the current operating stage of the robotic arm and the slot number of the wafer to be picked up. The height adjustment unit is used to take the preset height value corresponding to the slot number of the current wafer to be picked as the target height value, and control the lifting column to move up and down based on the target height value; The start control unit is used to control the telescopic shaft of the robot to extend to a preset coupling start position when the current operating phase is the start phase; The linkage control unit is used to control the telescopic axis and the rotary axis of the robot to operate in linkage according to preset trajectory information when the current operating stage is the coupled operating stage; The wafer centering control unit is used to, when the current operating stage is the wafer centering stage, acquire the actual height value of the lifting column, calculate the height difference between the actual height value and the target height value of the lifting column, determine a first compensation amount of the suction cup center in the X-axis direction based on the height difference and a preset first offset coefficient, determine a second compensation amount of the suction cup center in the Y-axis direction based on the height difference and a preset second offset coefficient, correct a preset target position based on the first compensation amount and the second compensation amount to obtain a corrected target position, and control the telescopic axis of the robot to move based on the corrected target position to move the suction cup center of the robot to the wafer center position; wherein, both the first offset coefficient and the second offset coefficient are linearly related to the mounting tilt angle of the suction cup.

[0007] A third aspect of this application provides an electronic device, including a memory, a processor, and a computer program stored in the memory and running on the processor, wherein the processor executes the computer program to implement the steps of the above-described robotic arm control method.

[0008] A fourth aspect of this application provides a front-end module, including a lifting column and a robotic arm that are communicatively connected to a controller. The lifting column is used to carry a wafer cassette, and the wafer cassette has multiple slots arranged sequentially along the height direction inside. The end of the robotic arm is provided with a suction cup for adsorbing wafers. The robotic arm uses the suction cup to sequentially remove wafers from each slot and transfer them to a processing station. The controller includes a memory, a processor, and a computer program stored in the memory and running on the processor. When the processor executes the computer program, it implements the steps of the robotic arm control method described above.

[0009] A fifth aspect of this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the above-described robotic arm control method.

[0010] The beneficial effects of the robotic arm control method and device, front-end module, electronic device and storage medium provided in the embodiments of this application are as follows: In the wafer picking process, the robot's movements are divided into multiple operating stages, each with corresponding action instructions, enabling precise timing control and interlocking control of the robot.

[0011] In the wafer centering stage, this embodiment considers that when the actual height of the lifting column matches the target height, the height of the suction cup and the wafer to be picked up are consistent. By controlling the robotic arm to perform the wafer picking action according to the preset target position, the center of the suction cup can be aligned with the center of the wafer, resulting in stable adsorption and preventing the wafer from easily detaching from the suction cup. However, as the front-end module is used for longer periods, the height control of the lifting column may deviate, causing a height difference (height difference in the Z-axis direction) between the suction cup and the wafer to be picked up. At this point, due to the suction cup's installation tilt angle, a geometric projection along the tilted suction cup axis decomposes the height difference in the Z-axis direction onto the XY plane, causing an equivalent positional offset of the suction cup center in the XY plane. If the robotic arm is still controlled to perform the wafer picking action according to the preset target position, the center of the suction cup cannot be aligned with the center of the wafer, reducing the adsorption fit and ultimately worsening the adsorption effect, thus increasing the frequency of wafer detachment.

[0012] Furthermore, the embodiments of this application demonstrate that the equivalent position offset of the suction cup center in the XY plane is linearly related to the height difference in the Z-axis direction. Therefore, by pre-calibrating the first offset coefficient and the second offset coefficient, during the wafer centering stage, the actual height value of the lifting column can be obtained first, compared with the target height value, and the height difference between the two can be calculated. This height difference is the height difference between the suction cup and the wafer. Multiplying the height difference by the first offset coefficient yields the first compensation amount of the suction cup center in the X-axis direction, and multiplying the height difference by the second offset coefficient yields the second compensation amount of the suction cup center in the Y-axis direction. Based on the first compensation amount and the second compensation amount, the preset target position is corrected. Based on the corrected target position, the telescopic axis of the robot arm is controlled to move, which can compensate for the equivalent position offset of the suction cup center in the XY plane caused by the height difference, thereby moving the suction cup center of the robot arm to the wafer center position and avoiding the problems of insufficient adsorption force and increased wafer detachment frequency caused by the offset of the suction cup center position. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 A flowchart illustrating a robotic arm control method provided in an embodiment of this application; Figure 2 A schematic diagram illustrating the geometric relationship between the height difference along the Z-axis and the total horizontal offset in the XY plane, provided in an embodiment of this application; Figure 3 This is a schematic diagram illustrating the geometric relationship between the total horizontal offset of the XY plane and the equivalent positional offsets in the X and Y axes, provided in an embodiment of this application. Figure 4 A schematic diagram of a region division method for a first bounding box and a second bounding box provided in an embodiment of this application; Figure 5 A structural block diagram of a robotic arm control device provided in an embodiment of this application; Figure 6 A schematic block diagram of an electronic device provided in an embodiment of this application; In the diagram, 41 represents the first enclosing box, and 42 represents the second enclosing box. Detailed Implementation

[0015] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0016] To make the objectives, technical solutions, and advantages of this application clearer, the following description will be provided in conjunction with the accompanying drawings and specific embodiments.

[0017] Please refer to Figure 1 , Figure 1 This is a flowchart illustrating a robotic arm control method provided in an embodiment of this application. The method is applied to the front-end module of a wafer processing equipment. The front-end module includes a lifting column and a robotic arm, both communicatively connected to a controller. The lifting column carries a wafer cassette, which has multiple slots arranged sequentially along its height. The end of the robotic arm is equipped with a suction cup for adsorbing wafers. The robotic arm uses the suction cup to sequentially remove wafers from each slot and transfer them to the processing station. This method is executed by the controller and includes: S101: Obtain the current operating stage of the robot and the slot number of the wafer to be picked.

[0018] In this embodiment, the robotic arm is a two-axis robotic arm, including a telescopic axis (R-axis) and a rotary axis (θ-axis). Through the coordination of the telescopic axis (R-axis) and the rotary axis (θ-axis), it can perform actions such as telescoping, rotating, and wafer retrieval. To facilitate the control of the robotic arm's action sequence and avoid collisions between the robotic arm and the lifting column, this embodiment divides the robotic arm's actions into multiple operating stages. Each operating stage has a corresponding action command to achieve precise timing control and interlocking control of the robotic arm. Correspondingly, when the controller issues an action command, it records the tag of the corresponding operating stage. Based on the tag of the operating stage, the current operating stage of the robotic arm can be determined.

[0019] For example, in this embodiment, the robot's movements are divided into an initial stage, a coupled operation stage, and a wafer centering stage. The control method for each stage is described in detail in steps S103 to S105 below.

[0020] The wafer cassette contains multiple slots corresponding to different heights, each with a unique slot number. By obtaining the slot number of the wafer to be retrieved, the target operating height for this retrieval can be determined. The slot number of the wafer to be retrieved can be detected by a photoelectric sensor, proximity switch, or visual recognition module located next to the lifting column / wafer cassette, or other methods can be used, as detailed in the following embodiments.

[0021] S102: Use the preset height value corresponding to the slot number of the current wafer to be picked as the target height value, and control the lifting column to move up and down based on the target height value.

[0022] In this embodiment, since the robotic arm is a two-axis robotic arm, it cannot adjust the height. In order to adapt to the change of wafer slot, the height of the lifting column can be dynamically adjusted according to the slot number of the wafer to be picked up, so that the height of the wafer to be picked up is precisely aligned with the picking height of the robotic arm.

[0023] Specifically, a preset height value can be assigned to each slot number in advance. For example, the preset height value corresponding to slot number 1 is the first height. Adjusting the height of the lifting column to this preset height value ensures that the height of slot number 1 is precisely aligned with the robot's pick-up height. When the slot number changes from 1 to 2 (slot number 2 is above slot number 1), the preset height value is lowered from the first height to the second height, and the height of the lifting column is also lowered from the first height to the second height. This ensures that the height of the slot to be calibrated is always at the robot's pick-up height when the slot number changes.

[0024] Based on the preset height value corresponding to each slot number, the preset height value corresponding to the slot number of the current wafer to be picked can be used as the target height value. The height of the lifting column is adjusted to the target height value, so that when the slot number changes, the height of the current wafer to be picked is always at the picking height of the robot arm, ensuring smooth wafer picking.

[0025] S103: If the current operating stage is the initial stage, control the extension shaft of the robot arm to extend to the preset coupling start position.

[0026] In this embodiment, during the initial stage, the robot arm begins its movement from the origin position. At the origin position, the telescopic shaft is fully retracted, and the robot arm's cantilever is close to the lifting column, resulting in insufficient clearance for rotational operations. Therefore, extending the telescopic shaft to the coupling start point position and extending the cantilever outward in a straight line moves the robot arm's main body and movement area away from the column, increasing the safe rotation distance and preventing interference and collision with the lifting column during subsequent two-axis linkage and rotational movements. The preset coupling start point position can be determined in advance through teaching.

[0027] S104: If the current operating stage is the coupled operating stage, the telescopic axis and the rotary axis of the control robot will operate in conjunction according to the preset trajectory information.

[0028] In this embodiment, preset trajectory information can be collected and saved in advance through teaching. The telescopic and rotary axes of the robot can be controlled according to the preset trajectory information, so that the linear telescopic motion and the rotary motion are synchronized. The two axes are coupled and linked to synthesize a smooth curved trajectory, which helps to avoid interference and collision with the lifting column.

[0029] Teaching is a common trajectory input method for industrial robots. During teaching, the operator manually moves the robot from the origin to the wafer cassette position. The controller records parameters such as the extension length and speed of the telescopic shaft, the rotation angle and speed of the rotary shaft at multiple trajectory points at preset time intervals (e.g., 1ms). This information is extracted for the coupled operation phase and saved as the target extension length, target extension speed, target rotation angle, and target rotation speed of the telescopic shaft, respectively, thus obtaining the preset trajectory information. This trajectory information can then be reproduced during subsequent automatic operation of the robot.

[0030] For example, controlling the telescopic and rotary axes of the robotic arm to operate in conjunction with preset trajectory information can include: Interpolation calculations are performed sequentially based on the target extension length and target extension speed of each pair of adjacent trajectory nodes to obtain the telescopic axis control command; interpolation calculations are also performed sequentially based on the target rotation angle and target rotation speed of each pair of adjacent trajectory nodes to obtain the rotation axis control command. Synchronously output telescopic shaft control commands and rotary shaft control commands to control the telescopic shaft and rotary shaft to operate in conjunction.

[0031] In this embodiment, the controller can sequentially read the target trajectory information of each axis corresponding to multiple trajectory nodes in the preset trajectory information (target extension length of the telescopic axis, target extension speed of the telescopic axis, target rotation angle of the rotation axis, and target rotation speed of the rotation axis). For each pair of adjacent trajectory nodes, interpolation calculation is performed based on the target extension length and target extension speed of the two adjacent trajectory nodes to obtain the telescopic axis control command. Interpolation calculation is also performed based on the target rotation angle and target rotation speed of the two adjacent trajectory nodes to obtain the rotation axis control command. Through interpolation calculation, discrete trajectory node parameters can be transformed into continuous and smooth dynamic control commands, ensuring a smooth transition in the motion position and speed of each axis. The interpolation calculation can be implemented using the existing cubic spline interpolation method to make the transition between trajectory nodes more natural.

[0032] S105: If the current operating stage is the wafer centering stage, then obtain the actual height value of the lifting column, calculate the height difference between the actual height value and the target height value of the lifting column, determine the first compensation amount of the suction cup center in the X-axis direction based on the height difference and the preset first offset coefficient, and determine the second compensation amount of the suction cup center in the Y-axis direction based on the height difference and the preset second offset coefficient; correct the preset target position based on the first compensation amount and the second compensation amount to obtain the corrected target position, and control the telescopic axis of the robot arm to move the suction cup center of the robot arm to the wafer center position based on the corrected target position; wherein, the first offset coefficient and the second offset coefficient are both linearly related to the installation tilt angle of the suction cup.

[0033] In this embodiment, during the wafer centering stage, the robot arm has moved to the wafer cassette position. At this time, the telescopic shaft can be extended to drive the end suction cup to move to the wafer position and remove the wafer from the wafer cassette.

[0034] Through extensive experimentation, the inventors discovered that the main reason for the increased frequency of wafers detaching from the chuck during wafer loading is that the chuck is not vertically mounted at the end of the robotic arm. Specifically, there is an angle (0.5°~3°) between the chuck's normal direction and the vertical direction (Z-axis direction), which is called the chuck's mounting angle. Due to this angle, the chuck is tilted during wafer loading and unloading, avoiding the wafer cassette edge. Furthermore, without the angle, the pressure distribution between the chuck and the wafer is "low in the middle and high at the edges" due to the strong airflow at the center and weak airflow at the edges. This makes the wafer easily "dimpled" by the low pressure at the center, causing the edges to lift, resulting in unstable adsorption. Setting the mounting angle creates a "wedge-shaped gap" between the chuck and the wafer along the tilt direction, meaning a larger gap on the inlet side and a smaller gap on the outlet side. As the airflow moves from the larger gap to the smaller gap, the velocity gradually increases and the pressure gradually decreases, flattening the low-pressure area concentrated in the center and improving the uniformity of pressure distribution, thereby enhancing adsorption stability.

[0035] On the other hand, when the actual height of the lifting column matches the target height, the height of the suction cup and the wafer to be picked up are consistent. The robot arm is controlled to perform the wafer-picking action according to the preset target position, the center of the suction cup can be aligned with the center of the wafer, the adsorption is stable, and the wafer is less likely to fall off the suction cup. However, as the front-end module is used for longer periods, the height control of the lifting column may deviate, resulting in a height difference between the suction cup and the wafer to be picked up. Although a floating mechanism (e.g., a spring floating mechanism that uses spring elastic deformation to adaptively offset the height difference) can be set in the suction cup mounting base to compensate for the height difference in the Z-axis direction, due to the installation tilt angle, the height difference in the Z-axis direction will be decomposed into the XY plane when geometrically projected along the tilted suction cup axis. This causes an equivalent positional offset of the suction cup center in the XY plane. If the wafer-picking action is still performed according to the preset target position, the suction cup center cannot be aligned with the wafer center, the adsorption adhesion decreases, and ultimately the adsorption effect deteriorates, increasing the probability of wafer detachment. The preset target position can be set through teaching.

[0036] Furthermore, from a geometric perspective, such as Figure 2 As shown, assuming the installation tilt angle is α and the height difference in the Z-axis direction is ΔZ, then the total horizontal offset in the XY plane is ΔL = ΔZ × tanα; Figure 3 As shown, assume the angle between ΔL and the X-axis is α. x The angle between ΔL and the Y-axis is α. y Then the equivalent position offset in the X-axis direction is obtained as ΔX = ΔL × cosα. x The equivalent position offset in the Y-axis direction is ΔY = ΔL × cosα y Therefore, it can be concluded that due to the installation tilt angles α and α' x and α y Since all parameters are fixed, the equivalent position offset ΔX in the X-axis direction and the height difference ΔZ in the Z-axis direction, as well as the equivalent position offset ΔY in the Y-axis direction and the height difference ΔZ in the Z-axis direction, are linearly related.

[0037] Therefore, a first offset coefficient between ΔX and ΔZ, and a second offset coefficient between ΔY and ΔZ can be pre-calibrated. Based on this, during the wafer centering stage, the actual height of the lifting column can be obtained first, compared with the target height, and the height difference ΔZ between the two can be calculated. This height difference ΔZ is the height difference between the suction cup and the wafer to be picked up. Multiplying ΔZ by the first offset coefficient yields the first compensation amount of the suction cup center in the X-axis direction, and multiplying the height difference ΔZ by the second offset coefficient yields the second compensation amount of the suction cup center in the Y-axis direction. Based on the first and second compensation amounts, the preset target position is corrected. Based on the corrected target position, the telescopic axis of the robot arm is controlled to move, which can compensate for the equivalent position offset of the suction cup center in the XY plane caused by the height difference ΔZ, thereby moving the suction cup center of the robot arm to the wafer center position and avoiding the problems of insufficient adsorption force and increased wafer detachment frequency caused by the offset of the suction cup center position.

[0038] In one embodiment of this application, the preset target position includes a first coordinate value in the X-axis direction and a second coordinate value in the Y-axis direction; Specifically, a first compensation amount in the X-axis direction of the suction cup center is determined based on the height difference and a preset first offset coefficient; a second compensation amount in the Y-axis direction of the suction cup center is determined based on the height difference and a preset second offset coefficient; and a preset target position is corrected based on the first and second compensation amounts to obtain the corrected target position, including: If the height difference is greater than the preset deviation threshold, the first compensation amount of the suction cup center in the X-axis direction is determined based on the height difference and the preset first offset coefficient, and the second compensation amount of the suction cup center in the Y-axis direction is determined based on the height difference and the preset second offset coefficient. The first corrected coordinate value in the X-axis direction is determined based on the first coordinate value and the first compensation amount in the X-axis direction; the second corrected coordinate value in the Y-axis direction is determined based on the second coordinate value and the second compensation amount in the Y-axis direction; The corrected target position is determined based on the first and second corrected coordinate values.

[0039] In this embodiment, when correcting the preset target position based on the height difference, the height difference can be compared with a preset deviation threshold first, and the corresponding correction method can be determined based on the comparison result.

[0040] Specifically, the preset target position (including the first coordinate value in the X-axis direction and the second coordinate value in the Y-axis direction) is taught when the height difference between the actual height value and the target height value of the lifting column is 0. The preset deviation threshold can be 1mm. When the height difference exceeds the deviation threshold, it indicates that the height difference is large. At this time, the height difference can be multiplied by the preset first offset coefficient to obtain the first compensation amount of the suction cup center in the X-axis direction. The height difference can be multiplied by the preset second offset coefficient to obtain the second compensation amount of the suction cup center in the Y-axis direction.

[0041] Furthermore, in this embodiment, the calibration stage uses ΔX = Xm - Xm' and ΔY = Ym - Ym', where Xm represents the theoretical coordinate value in the X-axis direction (corresponding to the first coordinate value), Xm' represents the corrected coordinate value in the X-axis direction (corresponding to the first corrected coordinate value), Ym represents the theoretical coordinate value in the Y-axis direction (corresponding to the second coordinate value), and Ym' represents the corrected coordinate value in the Y-axis direction (corresponding to the second corrected coordinate value). Therefore, after obtaining the first compensation amount of the suction cup center in the X-axis direction and the second compensation amount of the suction cup center in the Y-axis direction, subtracting the first compensation amount from the first coordinate value in the X-axis direction yields the first corrected coordinate value in the X-axis direction, and subtracting the second compensation amount from the second coordinate value in the Y-axis direction yields the second corrected coordinate value in the Y-axis direction. The position determined by the first and second corrected coordinate values ​​is the corrected target position. It should be noted that, depending on the installation tilt angle of the suction cup, the first offset coefficient and the second offset coefficient may be positive or negative. Correspondingly, the first compensation amount of the suction cup center in the X-axis direction and the second compensation amount of the suction cup center in the Y-axis direction may be positive or negative.

[0042] When the height difference is less than or equal to the deviation threshold, it indicates that the height difference is small. The offset in the XY plane caused by the suction cup installation tilt angle will not cause significant centering deviation of the suction cup or affect the adsorption effect, and can be ignored. At this time, the compensation amounts in the X and Y axis directions are both set to zero, and the original preset target position is directly used as the corrected target position, without the need to perform offset compensation.

[0043] As can be seen from the above, this embodiment, by setting a deviation threshold, only performs the target position correction operation when the height difference is greater than the deviation threshold. This can shield small deviations caused by minor assembly tolerances of the equipment, avoid positioning oscillations caused by frequent corrections of the target position, and simplify the control logic.

[0044] In one embodiment of this application, the following steps can be used to determine the slot number of the wafer to be retrieved: Get the slot number of the most recently retrieved wafer; If the slot number of the wafer already taken is the preset maximum slot number, then the preset starting slot number will be used as the slot number of the wafer to be taken. Otherwise, the slot number of the wafer that has already been picked up is increased by a preset step size to obtain the slot number of the wafer to be picked up.

[0045] In this embodiment, the slot number of the most recently retrieved wafer is the slot number of the last completed wafer retrieval, i.e., the previous slot number. If the previous slot number is the maximum number preset (e.g., 30), it indicates that the wafer cassette is empty. After the wafer cassette is replaced, the current retrieval will start from the first slot of the wafer cassette, and the starting slot number will be used as the slot number of the current wafer to be retrieved. If the previous slot number is not the maximum slot number, a preset step size (e.g., 1) will be added to the previous slot number as the slot number of the current wafer to be retrieved.

[0046] The method in this embodiment automatically updates the slot number at a fixed step size, which can complete the sequential grabbing of the entire box of wafers in an orderly manner. The control logic is simple and the operation is stable.

[0047] In one embodiment of this application, during the coupled operation phase of the robotic arm, the robotic arm control method further includes: Obtain the actual extension length of the telescopic shaft and the actual rotation angle of the rotating shaft; The contour information of the robot is determined based on the actual extension length and actual rotation angle; Based on the contour information of the robotic arm and the preset contour information of the lifting column, the minimum distance between the robotic arm and the lifting column is calculated. If the minimum distance is less than the preset distance threshold, the telescopic axis and the rotation axis will stop moving.

[0048] In this embodiment, a global coordinate system for the front-end module can be pre-established, and the inherent external dimensions and structural parameters of the robot and the lifting column can be stored. Based on this, during the operation of the robot, the actual extension length of the telescopic shaft and the actual rotation angle of the rotating shaft are collected in real time. The three-dimensional coordinates of each key feature point in the robot's contour (denoted as the first coordinate set) are solved through kinematic operations, and the first coordinate set is used as the contour information of the robot.

[0049] Furthermore, the preset contour information of the lifting column includes the three-dimensional coordinates of multiple key feature points within the lifting column (denoted as the second coordinate set). The Euclidean distance between each coordinate point in the first coordinate set and each coordinate point in the second coordinate set is calculated, and the minimum Euclidean distance is selected as the minimum distance between the robot and the lifting column. If the minimum distance is less than a preset distance threshold, it indicates that the robot and the lifting column are about to interfere and collide. At this time, the telescopic and rotary axes are controlled to stop moving, which can prevent the action from occurring before the collision, effectively protecting the robot's operational safety. If the minimum distance is greater than or equal to the preset distance threshold, it indicates that there is currently no risk of collision between the robot and the lifting column, and the telescopic and rotary axes of the robot can be controlled to operate normally according to the preset trajectory information.

[0050] It should be noted that the above-mentioned collision avoidance detection can also be performed during the initial stage of the robotic arm and the wafer centering stage.

[0051] Preferably, in one embodiment of this application, when calculating the minimum distance between the robot arm and the lifting column based on the contour information of the robot arm and the preset contour information of the lifting column, the following method can be used: The minimum bounding box of the robot arm is determined based on the outline information of the robot arm, which serves as the first bounding box; the minimum bounding box of the lifting column is determined based on the preset outline information of the lifting column, which serves as the second bounding box. The first bounding box is divided into multiple first regions along its circumference; the second bounding box is divided into multiple second regions along its circumference. N three-dimensional coordinate points are selected from each first region as first sampling points; N three-dimensional coordinate points are selected from each second region as second sampling points; the Euclidean distance between each first sampling point and each second sampling point is calculated as the region distance; the first sampling point and the second sampling point with the smallest corresponding region distance are selected as the first target coordinate point and the second target coordinate point, respectively; where N is a natural number and N≥2; The region where the first target point is located, and the neighboring region of the region where the first target point is located, are defined as the first target region; the region where the second target point is located, and the neighboring region of the region where the second target point is located, are defined as the second target region. Calculate the Euclidean distance between each three-dimensional coordinate point in the first target area and each three-dimensional coordinate point in the second target area, and use this distance as the target area distance. The minimum target area distance is taken as the minimum distance between the robot arm and the lifting column.

[0052] In this embodiment, both the first and second enclosing boxes can be cylindrical enclosing boxes, as shown in the schematic diagram of their area division. Figure 4 As shown. In Figure 4In the middle, the first enclosing box 41 is divided into 8 first regions according to a preset angle (45°), and the second enclosing box 42 is divided into 8 second regions.

[0053] Subsequently, at least two 3D coordinate points are sampled within each first region as the first sampling point, and at least two 3D coordinate points are sampled within each second region as the second sampling point. The Euclidean distance between each first sampling point and each second sampling point is calculated as the region distance. The sampling point pair with the closest region distance is selected as the first target coordinate point and the second target coordinate point. Based on this, the region containing the first target point and its neighboring region is designated as the first target region, and the region containing the second target point and its neighboring region is designated as the second target region. This step allows for the rapid identification of the closest local regions on the two bounding boxes, excluding regions with no interference risk and reducing the scope of subsequent calculations.

[0054] Finally, the distance calculation of all three-dimensional coordinate points in the first target area and the second target area is performed, and the minimum distance is taken as the minimum distance between the robot arm and the lifting column.

[0055] As can be seen from the above, in this embodiment, when calculating the minimum distance between the robot and the lifting column, the closest local area on the two bounding boxes is locked first, and then the distance calculation of all three-dimensional coordinate points is performed in the local area. This can reduce the amount of calculation while ensuring accurate calculation of the minimum distance.

[0056] Corresponding to the robotic arm control method in the above embodiments, Figure 5 This is a structural block diagram of a robotic arm control device according to an embodiment of this application. The device is housed in a controller, which is applied to the front-end module of a wafer processing equipment. The front-end module also includes a lifting column and a robotic arm, both communicatively connected to the controller. The lifting column carries a wafer cassette, which has multiple slots arranged sequentially along its height. The end of the robotic arm is equipped with a suction cup for adsorbing wafers. The robotic arm uses the suction cup to sequentially remove wafers from each slot and transfer them to the processing station. For ease of explanation, only the parts relevant to the embodiment of this application are shown. (Reference) Figure 5 The robotic arm control device 20 includes: a data acquisition unit 21, a height adjustment unit 22, a start control unit 23, a linkage control unit 24, and a wafer centering control unit 25.

[0057] The data acquisition unit 21 is used to acquire the current operating stage of the robot and the slot number of the wafer to be picked. The height adjustment unit 22 is used to take the preset height value corresponding to the slot number of the current wafer to be picked as the target height value, and control the lifting column to move up and down based on the target height value; The start control unit 23 is used to control the telescopic shaft of the robot to extend to a preset coupling start position when the current operation phase is the start phase. The linkage control unit 24 is used to control the telescopic axis and the rotary axis of the robot to operate in linkage according to the preset trajectory information when the current operation stage is the coupled operation stage; The wafer centering control unit 25 is used to acquire the actual height value of the lifting column when the current operating stage is the wafer centering stage, calculate the height difference between the actual height value and the target height value of the lifting column, determine the first compensation amount of the suction cup center in the X-axis direction based on the height difference and the preset first offset coefficient, determine the second compensation amount of the suction cup center in the Y-axis direction based on the height difference and the preset second offset coefficient, correct the preset target position based on the first compensation amount and the second compensation amount to obtain the corrected target position, and control the telescopic axis of the robot to move the suction cup center of the robot to the wafer center position based on the corrected target position; wherein, the first offset coefficient and the second offset coefficient are both linearly related to the installation tilt angle of the suction cup.

[0058] In one embodiment of this application, the preset target position includes a first coordinate value in the X-axis direction and a second coordinate value in the Y-axis direction; the wafer centering control unit 25 is specifically used for: If the height difference is greater than the preset deviation threshold, the first compensation amount of the suction cup center in the X-axis direction is determined based on the height difference and the preset first offset coefficient, and the second compensation amount of the suction cup center in the Y-axis direction is determined based on the height difference and the preset second offset coefficient. The first corrected coordinate value in the X-axis direction is determined based on the first coordinate value and the first compensation amount in the X-axis direction; the second corrected coordinate value in the Y-axis direction is determined based on the second coordinate value and the second compensation amount in the Y-axis direction; The corrected target position is determined based on the first and second corrected coordinate values.

[0059] In one embodiment of this application, the wafer centering control unit 25 is specifically used for: If the height difference is less than or equal to the preset deviation threshold, then both the first compensation amount and the second compensation amount are set to zero, and the target position is taken as the corrected target position.

[0060] In one embodiment of this application, the data acquisition unit 21 is specifically used for: Get the slot number of the most recently retrieved wafer; If the slot number of the wafer already taken is the preset maximum slot number, then the preset starting slot number will be used as the slot number of the wafer to be taken. Otherwise, the slot number of the wafer that has already been picked up is increased by a preset step size to obtain the slot number of the wafer to be picked up.

[0061] In one embodiment of this application, the preset trajectory information includes target trajectory information for each of multiple trajectory nodes; the target trajectory information for the axis includes the target extension length of the telescopic axis, the target extension speed of the telescopic axis, the target rotation angle of the rotating axis, and the target rotation speed of the rotating axis; the linkage control unit 24 is specifically used for: Interpolation calculations are performed sequentially based on the target extension length and target extension speed of each pair of adjacent trajectory nodes to obtain the telescopic axis control command; interpolation calculations are also performed sequentially based on the target rotation angle and target rotation speed of each pair of adjacent trajectory nodes to obtain the rotation axis control command. Synchronously output telescopic shaft control commands and rotary shaft control commands to control the telescopic shaft and rotary shaft to operate in conjunction.

[0062] In one embodiment of this application, the linkage control unit 24 is further configured to: Obtain the actual extension length of the telescopic shaft and the actual rotation angle of the rotating shaft; The contour information of the robot is determined based on the actual extension length and actual rotation angle; Based on the contour information of the robotic arm and the preset contour information of the lifting column, the minimum distance between the robotic arm and the lifting column is calculated. If the minimum distance is less than the preset distance threshold, the telescopic axis and the rotation axis will stop moving.

[0063] See Figure 6 , Figure 6 This is a schematic block diagram of an electronic device provided according to an embodiment of this application. Figure 6 The electronic device 300 in this embodiment may include one or more processors 301, one or more input devices 302, one or more output devices 303, and one or more memories 304. The processors 301, input devices 302, output devices 303, and memories 304 communicate with each other via a communication bus 305. The memories 304 store computer programs, including program instructions. The processors 301 execute the program instructions stored in the memories 304. Specifically, the processors 301 are configured to invoke the program instructions to perform the functions of the units in the aforementioned device embodiments, for example... Figure 5 The data acquisition unit 21, height adjustment unit 22, start control unit 23, linkage control unit 24, and wafer centering control unit 25 are shown to have the following functions. In this embodiment, the electronic device 300 may include the controller shown above.

[0064] It should be understood that, in the embodiments of this application, the processor 301 may be a central processing unit (CPU), or it may be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor.

[0065] Input device 302 may include a touchpad, a fingerprint sensor (for collecting the user's fingerprint information and fingerprint orientation information), a microphone, etc., and output device 303 may include a display (LCD, etc.), a speaker, etc.

[0066] The memory 304 may include read-only memory and random access memory, and provides instructions and data to the processor 301. A portion of the memory 304 may also include non-volatile random access memory. For example, the memory 304 may also store preset information such as deviation thresholds, maximum slot numbers, and outline information of the lifting column.

[0067] In specific implementations, the processor 301, input device 302, and output device 303 described in the embodiments of this application can execute the implementation method described in the robotic arm control method provided in the embodiments of this application, or they can execute the implementation method of the electronic device described in the embodiments of this application, which will not be repeated here.

[0068] In another embodiment of this application, a front-end module is provided, including a lifting column and a robot arm that are respectively communicatively connected to a controller. The lifting column is used to carry a wafer box. The wafer box has multiple slots arranged sequentially along the height direction. The robot arm is used to sequentially remove wafers from each slot and transfer them to a processing station. The end of the robot arm is provided with a suction cup for adsorbing wafers. The controller includes a memory, a processor, and a computer program stored in the memory and running on the processor. When the processor executes the computer program, it implements the steps of the robot arm control method described above.

[0069] In another embodiment of this application, a computer-readable storage medium is provided. This computer-readable storage medium stores a computer program, which includes program instructions. When executed by a processor, the program instructions implement all or part of the processes in the methods described above. Alternatively, the computer program can instruct related hardware to complete the process. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include any entity or device capable of carrying computer program code, a recording medium, a USB flash drive, a portable hard drive, a magnetic disk, an optical disk, a computer memory, a read-only memory (ROM), a random access memory (RAM), an electrical carrier signal, a telecommunication signal, and a software distribution medium, etc.

[0070] The computer-readable storage medium can be an internal storage unit of the electronic device in any of the foregoing embodiments, such as a hard disk or memory of the electronic device. The computer-readable storage medium can also be an external storage device of the electronic device, such as a plug-in hard disk, smart media card (SMC), secure digital card (SD), flash card, etc., equipped on the electronic device. Furthermore, the computer-readable storage medium can include both internal and external storage units of the electronic device. The computer-readable storage medium is used to store computer programs and other programs and data required by the electronic device. The computer-readable storage medium can also be used to temporarily store data that has been output or will be output.

[0071] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this application.

[0072] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the electronic devices and units described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0073] In the several embodiments provided in this application, it should be understood that the disclosed electronic devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units 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 an indirect coupling or communication connection through some interfaces or units, or it may be an electrical, mechanical, or other form of connection.

[0074] The units described as separate components may or may not be physically separate. The components shown as units 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 units can be selected to achieve the purpose of the embodiments of this application, depending on actual needs.

[0075] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0076] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A robotic arm control method applied to the front-end module of a wafer processing equipment, the front-end module comprising a lifting column and a robotic arm respectively communicatively connected to a controller, the lifting column for supporting a wafer cassette, the wafer cassette having multiple slots arranged sequentially along the height direction inside, the end of the robotic arm being provided with a suction cup for adsorbing wafers, the robotic arm using the suction cup to sequentially remove wafers from each slot and transfer them to the processing station, the method being executed by the controller, characterized in that... include: Obtain the current operating stage of the robotic arm and the slot number of the wafer to be retrieved; The preset height value corresponding to the slot number of the current wafer to be retrieved is used as the target height value, and the lifting column is controlled to move up and down based on the target height value; If the current operating stage is the initial stage, then control the telescopic shaft of the robot to extend to the preset coupling starting point position; If the current operating stage is a coupled operating stage, then control the telescopic axis and the rotary axis of the robot to operate in conjunction according to the preset trajectory information; If the current operating stage is the wafer centering stage, then the actual height value of the lifting column is obtained, the height difference between the actual height value and the target height value of the lifting column is calculated, the first compensation amount of the suction cup center in the X-axis direction is determined based on the height difference and the preset first offset coefficient, the second compensation amount of the suction cup center in the Y-axis direction is determined based on the height difference and the preset second offset coefficient, and the preset target position is corrected based on the first compensation amount and the second compensation amount to obtain the corrected target position; Based on the corrected target position, the telescopic axis of the robot is controlled to move to the center of the robot's suction cup to the center of the wafer; wherein, the first offset coefficient and the second offset coefficient are both linearly related to the mounting angle of the suction cup.

2. The robotic arm control method as described in claim 1, characterized in that, The preset target position includes a first coordinate value in the X-axis direction and a second coordinate value in the Y-axis direction; Specifically, a first compensation amount in the X-axis direction of the suction cup center is determined based on the height difference and a preset first offset coefficient; a second compensation amount in the Y-axis direction of the suction cup center is determined based on the height difference and a preset second offset coefficient; and a preset target position is corrected based on the first compensation amount and the second compensation amount to obtain the corrected target position, including: If the height difference is greater than a preset deviation threshold, then a first compensation amount for the suction cup center in the X-axis direction is determined based on the height difference and a preset first offset coefficient, and a second compensation amount for the suction cup center in the Y-axis direction is determined based on the height difference and a preset second offset coefficient. A first corrected coordinate value in the X-axis direction is determined based on the first coordinate value in the X-axis direction and the first compensation amount; a second corrected coordinate value in the Y-axis direction is determined based on the second coordinate value in the Y-axis direction and the second compensation amount; The corrected target position is determined based on the first corrected coordinate value and the second corrected coordinate value.

3. The robotic arm control method as described in claim 1, characterized in that, The process involves determining a first compensation amount for the suction cup center in the X-axis direction based on the height difference and a preset first offset coefficient, determining a second compensation amount for the suction cup center in the Y-axis direction based on the height difference and a preset second offset coefficient, and correcting a preset target position based on the first compensation amount and the second compensation amount to obtain a corrected target position, including: If the height difference is less than or equal to a preset deviation threshold, then both the first compensation amount and the second compensation amount are set to zero, and the target position is taken as the corrected target position.

4. The robotic arm control method as described in claim 1, characterized in that, The method for determining the slot number of the current wafer to be retrieved includes: Get the slot number of the most recently retrieved wafer; If the slot number of the wafer that has been picked up is the preset maximum slot number, then the preset starting slot number will be used as the slot number of the wafer to be picked up. Otherwise, the slot number of the already retrieved wafer is increased by a preset step size to obtain the slot number of the current wafer to be retrieved.

5. The robotic arm control method as described in claim 1, characterized in that, The preset trajectory information includes the target trajectory information of the axis corresponding to each of the multiple trajectory nodes; the target trajectory information of the axis includes the target extension length of the telescopic axis, the target extension speed of the telescopic axis, the target rotation angle of the rotating axis, and the target rotation speed of the rotating axis; The control of the telescopic and rotary axes of the robotic arm to operate in conjunction with preset trajectory information includes: Interpolation calculations are performed sequentially based on the target extension length and target extension speed of each pair of adjacent trajectory nodes to obtain the telescopic axis control command; interpolation calculations are also performed sequentially based on the target rotation angle and target rotation speed of each pair of adjacent trajectory nodes to obtain the rotation axis control command. The telescopic shaft control command and the rotary shaft control command are output synchronously to control the telescopic shaft and the rotary shaft to operate in conjunction.

6. The robotic arm control method as described in claim 5, characterized in that, Also includes: Obtain the actual extension length of the telescopic shaft and the actual rotation angle of the rotating shaft; The contour information of the robotic arm is determined based on the actual extension length and the actual rotation angle; Based on the outline information of the robotic arm and the preset outline information of the lifting column, the minimum distance between the robotic arm and the lifting column is calculated. If the minimum distance is less than a preset distance threshold, then the telescopic axis and the rotating axis are controlled to stop moving.

7. A robotic arm control device, disposed in a controller, the controller being applied to the front-end module of a wafer processing equipment, the front-end module further comprising a lifting column and a robotic arm respectively communicatively connected to the controller, the lifting column being used to support a wafer cassette, the wafer cassette having a plurality of slots arranged sequentially along the height direction inside, the end of the robotic arm being provided with a suction cup for adsorbing wafers, the robotic arm using the suction cup to sequentially remove wafers from each slot and transfer them to the processing station, characterized in that, The device includes: The data acquisition unit is used to acquire the current operating stage of the robotic arm and the slot number of the wafer to be picked up. The height adjustment unit is used to take the preset height value corresponding to the slot number of the current wafer to be picked as the target height value, and control the lifting column to move up and down based on the target height value; The start control unit is used to control the telescopic shaft of the robot to extend to a preset coupling start position when the current operating phase is the start phase; The linkage control unit is used to control the telescopic axis and the rotary axis of the robot to operate in linkage according to preset trajectory information when the current operating stage is the coupled operating stage; The wafer centering control unit is used to, when the current operating stage is the wafer centering stage, acquire the actual height value of the lifting column, calculate the height difference between the actual height value and the target height value of the lifting column, determine a first compensation amount of the suction cup center in the X-axis direction based on the height difference and a preset first offset coefficient, determine a second compensation amount of the suction cup center in the Y-axis direction based on the height difference and a preset second offset coefficient, correct a preset target position based on the first compensation amount and the second compensation amount to obtain a corrected target position, and control the telescopic axis of the robot to move based on the corrected target position to move the suction cup center of the robot to the wafer center position; wherein, both the first offset coefficient and the second offset coefficient are linearly related to the mounting tilt angle of the suction cup.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method as described in any one of claims 1 to 6.

9. A front-end module comprising a lifting column and a robotic arm respectively communicatively connected to a controller, the lifting column for carrying a wafer cassette, the wafer cassette having a plurality of slots arranged sequentially along the height direction inside, the robotic arm having a suction cup at its end for adsorbing wafers, the robotic arm using the suction cup to sequentially remove wafers from each slot and transfer them to a processing station, the controller comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that... When the processor executes the computer program, it implements the steps of the method as described in any one of claims 1 to 6.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method as described in any one of claims 1 to 6.

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