Semiconductor workpiece grasping method and control system using disc transport

Abstract

The present disclosure proposes a method for grasping semiconductor workpieces using a disc transport, comprising: acquiring image data from an identification area of the disc; in the case where it is determined based on the acquired image data that a semiconductor workpiece exists in the workpiece position, converting the workpiece position to a first coordinate in a reference coordinate system based on the image data; using the first coordinate as a tracking interpolation position, controlling a manipulator to move to a position based on the first coordinate; controlling the manipulator to track the workpiece position based on the tracking interpolation position, the first coordinate, and the rotation information of the disc; and grasping the semiconductor workpiece from the grasping area of the disc when the polishing time meets the requirements. The embodiment of the present disclosure tracks the semiconductor workpiece in the workpiece position through image recognition, and grasps the workpiece on the disc when the polishing meets the time requirements, thereby replacing manual methods and meeting the polishing requirements of semiconductor workpieces.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a semiconductor workpiece grabbing method and control system using a disc transport. Background Art

[0002] Chemical polishing is a wafer processing process in which the polishing table is constantly rotating to ensure uniform distribution of the polishing liquid on the polishing cloth. Therefore, workpieces must be placed and loaded onto the rotating polishing table. Traditionally, this process has been performed manually.

[0003] Due to the particularity of the chemical polishing working environment, there is currently no method or control system for tracking and placing workpieces on a rotating polishing table. Summary of the Invention

[0004] An embodiment of the present invention provides a semiconductor workpiece grasping method and control system for disc conveying, which are used to grasp a semiconductor workpiece that is chemically polished and conveyed on a disc without stopping the conveyance of the disc.

[0005] The present disclosure provides a semiconductor workpiece grasping method for disc transport, wherein a plurality of workpiece positions are distributed on the disc, and the workpiece positions are used to accommodate semiconductor workpieces to be polished. The grasping method comprises: acquiring image data from an identification area of the disc, wherein the identification area can completely cover at least one workpiece position; when it is determined based on the acquired image data that a semiconductor workpiece exists in the workpiece position, converting the workpiece position to a first coordinate in a reference coordinate system based on the image data; using the first coordinate as a tracking interpolation position, controlling a manipulator to move to the position based on the first coordinate; controlling the manipulator to track the workpiece position based on the tracking interpolation position, the first coordinate and the rotation information of the disc; and grasping the semiconductor workpiece from the grasping area of the disc when the polishing time meets the requirements, wherein the grasping area does not overlap with the identification area.

[0006] In some embodiments, determining whether a semiconductor workpiece exists in the workpiece position is achieved by the following steps:

[0007] acquiring the image data;

[0008] Matching the image data with preset image data;

[0009] If the matching is successful, it is determined that a semiconductor workpiece exists in the workpiece position.

[0010] In some embodiments, using the first coordinate as a tracking interpolation position, and controlling the manipulator to move to a position based on the first coordinate includes:

[0011] Determine the second coordinate of the manipulator in the reference coordinate system;

[0012] determining a first coordinate deviation between the second coordinate and the first coordinate;

[0013] Based on the first coordinate deviation, the robot is controlled to move to the first coordinate, and a time deviation of the robot moving to the first coordinate is recorded.

[0014] In some embodiments, controlling the manipulator to track the workpiece position based on the tracking interpolation position, the first coordinate, and the rotation information of the disk includes:

[0015] determining a third coordinate after the disk rotates based on the first coordinate, the rotation information of the disk, and the time deviation;

[0016] determining a second coordinate deviation between the third coordinate and the first coordinate;

[0017] The robot is controlled to track the workpiece position based on the second coordinate deviation.

[0018] In some embodiments, the rotation information of the disk is obtained based on encoder information of the disk.

[0019] In some embodiments, the centers of the workpiece positions on the disk are distributed on a circle with a preset distance as a radius, and the center of the circle is the center of the disk.

[0020] The present disclosure also proposes a robot control system for grabbing a workpiece on a rotating disc, wherein a plurality of workpiece positions are distributed on the disc, and the workpiece positions are used to accommodate semiconductor workpieces to be polished. The robot control system includes a processor, which is configured to: acquire image data from an identification area of the disc, wherein the identification area can completely cover at least one workpiece position; when it is determined based on the acquired image data that a semiconductor workpiece exists in the workpiece position, convert the workpiece position to a first coordinate in a reference coordinate system based on the image data; use the first coordinate as a tracking interpolation position to control the manipulator to move to the position based on the first coordinate; control the manipulator to track the workpiece position based on the tracking interpolation position, the first coordinate and the rotation information of the disc; when the polishing time meets the requirements, grab the semiconductor workpiece from the grabbing area of the disc, wherein the grabbing area does not overlap with the identification area.

[0021] In some embodiments, the processor is further configured to:

[0022] Determine the second coordinate of the manipulator in the reference coordinate system;

[0023] determining a first coordinate deviation between the second coordinate and the first coordinate;

[0024] Based on the first coordinate deviation, the robot is controlled to move to the first coordinate, and a time deviation of the robot moving to the first coordinate is recorded.

[0025] In some embodiments, the processor is further configured to:

[0026] determining a third coordinate after the disk rotates based on the first coordinate, the rotation information of the disk, and the time deviation;

[0027] determining a second coordinate deviation between the third coordinate and the first coordinate;

[0028] The robot is controlled to track the workpiece position based on the second coordinate deviation.

[0029] The present disclosure further provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the steps of the semiconductor workpiece grabbing method using a disc transfer as described in each embodiment of the present disclosure are implemented.

[0030] The embodiment of the present disclosure tracks the semiconductor workpiece in the workpiece position through image recognition, and grabs the workpiece on the disc when polishing meets the time requirement, thereby replacing the manual method and meeting the polishing requirements of the semiconductor workpiece.

[0031] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are specifically listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present invention. The same reference symbols are used throughout the drawings to represent the same components. In the drawings:

[0033] Figure 1 A schematic diagram of the basic structure of the disc transport disclosed in the present invention;

[0034] Figure 2 is a basic flow chart of the semiconductor workpiece grasping method disclosed herein;

[0035] Figure 3 Schematic diagram of coordinate transformation of the semiconductor workpiece grasping method disclosed in the present invention. DETAILED DESCRIPTION

[0036] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0037] The present disclosure provides a method for grasping a semiconductor workpiece by a disc transport, such as Figure 1 As shown, there are multiple workpiece positions 32 distributed on the disc 3, and the workpiece position 32 is used to accommodate the semiconductor workpiece 33 to be polished. In this example, the disc is immersed in the polishing liquid, and when the semiconductor workpiece 33 is placed in the workpiece position 32, the disc 3 can drive the semiconductor workpiece to be polished. In actual scenarios, the difficulty of conveying the disc 3 lies in the rotation of the disc 3, rather than linear motion, and the position of the workpiece changes non-linearly. And the robot does not directly execute grasping after it follows the workpiece, but needs to meet the polishing time of the semiconductor workpiece, and cannot be polished for a long time. Based on this, Figure 2 As shown, the present disclosure proposes a method for grabbing a semiconductor workpiece using a disc transport, comprising:

[0038] In step S201, image data is acquired from the identification area of the disk, wherein the identification area can at least completely cover one workpiece position. Figure 1 As shown, a visual camera 2 can be provided to acquire image data from the disc's recognition area 21 in real time and transmit the acquired image data to the robot control system 1. In the present disclosure, the disc's recognition area 21 can cover at least one workpiece location 32 of the disc. Because the disc rotates about an axis, in some embodiments, the centers of the workpiece locations on the disc are distributed on a circle with a predetermined radius, and the center of the circle is the center of the disc. In other words, each workpiece location can be distributed on a circle with a predetermined radius.

[0039] In step S202, if it is determined based on the acquired image data that a semiconductor workpiece is present in the workpiece position, the workpiece position is converted to a first coordinate in a reference coordinate system based on the image data. In the present disclosure, whether a semiconductor workpiece is present in the workpiece position of the rotating disk is monitored in real time. If it is determined that a semiconductor workpiece is present, the workpiece position is converted to a first coordinate in the reference coordinate system. In specific operations, since the recognition area of the visual camera 2 is fixed, the coordinate position of the recognition area 21 can be determined, for example, in a plane coordinate system determined by the central axis of the disk as the reference coordinate system, thereby converting the workpiece position to the first coordinate in the reference coordinate system.

[0040] In step S203, the first coordinate is used as a tracking interpolation position, and the robot is controlled to move to the position based on the first coordinate. After determining the first coordinate, the robot is controlled to move using the first coordinate as the tracking interpolation position. During the robot movement, the disk 3 continues to rotate. Therefore, after the robot moves to the first coordinate, the semiconductor workpiece has moved a certain angle during this period. In subsequent steps, the robot can track the workpiece based on this.

[0041] In step S204, the robot is controlled to track the workpiece position based on the tracking interpolation position, the first coordinate, and the rotation information of the disk. In this process, the robot is controlled to approach the workpiece position.

[0042] In step S205 , when the polishing time meets the requirement, the semiconductor workpiece is grabbed from the grabbing area 31 of the disk, wherein the grabbing area 31 does not overlap with the identification area 21 .

[0043] Specifically, the system can record the polishing time of a semiconductor workpiece and the time the rotating disk has polished the workpiece. When polishing is about to be completed, the robot arm is controlled to track and grasp the workpiece within one full rotation of the disk. This method also avoids duplicate recognition of the semiconductor workpiece. Furthermore, the grasping area and the recognition area are set to non-overlapping, ensuring that grasping and recognition of the semiconductor workpiece are not performed simultaneously, thereby avoiding interference.

[0044] The embodiment of the present disclosure tracks the semiconductor workpiece in the workpiece position through image recognition, and grabs the workpiece on the disc when polishing meets the time requirement, thereby replacing the manual method and meeting the polishing requirements of the semiconductor workpiece.

[0045] In some embodiments, determining whether a semiconductor workpiece exists in the workpiece position is achieved by the following steps: acquiring the image data;

[0046] Matching the image data with preset image data;

[0047] If the matching is successful, it is determined that a semiconductor workpiece exists in the workpiece position.

[0048] As a specific example, image data of at least a portion of a workpiece position can be acquired and then compared with preset image data, where the preset image data may be taken when a semiconductor workpiece is present in the workpiece position. A specific comparison method may be to set a reference point or reference edge, and then rotate and / or scale the acquired image data to determine whether the acquired image data overlaps or partially overlaps with the preset image data. If it is determined that no semiconductor workpiece exists in the workpiece position, wait for image data of the next workpiece position to be acquired and then make another determination. If there is a match or a partial match, it is determined that a semiconductor workpiece exists in the workpiece position.

[0049] In some embodiments, using the first coordinate as a tracking interpolation position, and controlling the manipulator to move to a position based on the first coordinate includes:

[0050] Determine the second coordinate of the manipulator in the reference coordinate system;

[0051] determining a first coordinate deviation between the second coordinate and the first coordinate;

[0052] Based on the first coordinate deviation, the robot is controlled to move to the first coordinate, and a time deviation of the robot moving to the first coordinate is recorded.

[0053] like Figure 1 As shown, a manipulator is provided on the grasping robot 4 through a 6-axis joint, and the manipulator is used to grasp the semiconductor workpiece. The coordinates of the manipulator can be obtained by the robot control system 1, based on which the first coordinate deviation between the second coordinate and the first coordinate can be determined. The manipulator is further controlled to move to the first coordinate, and the time deviation of the manipulator moving to the first coordinate is recorded. That is, the method disclosed in the present invention first controls the manipulator to move to the first coordinate during the rotation of the disc. Figure 3 As shown, since the disk keeps rotating, after moving to the first coordinate p2, the disk runs for a corresponding time (p1 position), so it is impossible to complete the workpiece grasping. The present disclosure further records the time deviation of the robot moving to the first coordinate and tracks the semiconductor workpiece.

[0054] In some embodiments, controlling the manipulator to track the workpiece position based on the tracking interpolation position, the first coordinate, and the rotation information of the disk includes:

[0055] A third coordinate after the disk has rotated is determined based on the first coordinate, the disk rotation information, and the time offset. In some embodiments, the disk rotation information is obtained based on information from the disk encoder. That is, corresponding disk rotation speeds can be used for polishing different semiconductor workpieces, and the disk rotation information can be obtained based on the disk encoder information.

[0056] A second coordinate deviation between the third coordinate and the first coordinate is determined.

[0057] The robot is controlled to track the workpiece position based on the second coordinate deviation.

[0058] Specifically, during the grasping process, the disc keeps driving the workpiece to rotate, and its position is changing at any time. In the present disclosure, the robot is controlled to track the workpiece position based on the second coordinate deviation, so that the grasping position of the robot can be close to the workpiece position. For example, the position relationship can be fitted based on the rotation information of the disc to determine the position information of the semiconductor workpiece in the reference coordinate system at each moment in the future, and then the robot is controlled to track the workpiece position. In the present disclosure, by tracking, the robot can be kept in a state where it can grasp at any time, so that the semiconductor workpiece can be grasped out after the polishing time meets the requirements. During the chemical polishing process, the polishing time needs to be strictly controlled. The polishing time cannot be too short, otherwise it will not meet the requirements, and the polishing time should not be too long, otherwise it will over-polish and cause material loss. The method disclosed in the present disclosure can track the workpiece position where the semiconductor workpiece is present during the polishing process, and control the robot to grasp when the polishing time meets the requirements, thereby achieving the effects of grasping the semiconductor workpiece and controlling the polishing time at the same time.

[0059] The present disclosure also proposes a robot control system for grabbing a workpiece on a rotating disc, wherein a plurality of workpiece positions are distributed on the disc, and the workpiece positions are used to accommodate semiconductor workpieces to be polished. The robot control system includes a processor, which is configured to: acquire image data from an identification area of the disc, wherein the identification area can completely cover at least one workpiece position; when it is determined based on the acquired image data that a semiconductor workpiece exists in the workpiece position, convert the workpiece position to a first coordinate in a reference coordinate system based on the image data; use the first coordinate as a tracking interpolation position to control the manipulator to move to the position based on the first coordinate; control the manipulator to track the workpiece position based on the tracking interpolation position, the first coordinate and the rotation information of the disc; when the polishing time meets the requirements, grab the semiconductor workpiece from the grabbing area of the disc, wherein the grabbing area does not overlap with the identification area.

[0060] In some embodiments, the processor is further configured to:

[0061] Determine the second coordinate of the manipulator in the reference coordinate system;

[0062] determining a first coordinate deviation between the second coordinate and the first coordinate;

[0063] Based on the first coordinate deviation, the robot is controlled to move to the first coordinate, and a time deviation of the robot moving to the first coordinate is recorded.

[0064] In some embodiments, the processor is further configured to:

[0065] determining a third coordinate after the disk rotates based on the first coordinate, the rotation information of the disk, and the time deviation;

[0066] determining a second coordinate deviation between the third coordinate and the first coordinate;

[0067] The robot is controlled to track the workpiece position based on the second coordinate deviation.

[0068] The present disclosure further provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the steps of the semiconductor workpiece grabbing method using a disc transfer as described in each embodiment of the present disclosure are implemented.

[0069] It should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0070] The serial numbers of the above embodiments of the present invention are for description only and do not represent the advantages or disadvantages of the embodiments.

[0071] Through the description of the above embodiments, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus the necessary general hardware platform, and of course can also be implemented by hardware, but in many cases the former is a better embodiment. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), and includes a number of instructions for enabling a terminal (which can be a mobile phone, computer, server or network device, etc.) to execute the methods described in each embodiment of the present invention.

[0072] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the present invention and the claims, all of which are protected by the present invention.

Claims

1. A method for grabbing semiconductor workpieces using a disc transport, characterized in that: A plurality of workpiece positions are distributed on the disc, and the workpiece positions are used to accommodate semiconductor workpieces to be polished. The grasping method includes: Acquiring image data from an identification area of the disk, wherein the identification area is capable of completely covering at least one workpiece position; In a case where it is determined based on the acquired image data that a semiconductor workpiece exists in the workpiece position, converting the workpiece position to a first coordinate in a reference coordinate system based on the image data; Using the first coordinate as a tracking interpolation position, controlling the manipulator to move to the first coordinate; Controlling the manipulator to track the workpiece position based on the tracking interpolation position, the first coordinate, and the rotation information of the disk; When the polishing time meets the requirement, the semiconductor workpiece is grabbed from the grabbing area of the disk, wherein the grabbing area does not overlap with the identification area. When the polishing is about to be completed, the manipulator is controlled to perform tracking operation and complete the grabbing within one rotation of the disk. Using the first coordinate as a tracking interpolation position and controlling the manipulator to move to the first coordinate includes: Determine the second coordinate of the manipulator in the reference coordinate system; determining a first coordinate deviation between the second coordinate and the first coordinate; Based on the first coordinate deviation, controlling the manipulator to move to the first coordinate, and recording the time deviation of the manipulator moving to the first coordinate; Controlling the manipulator to track the workpiece position based on the tracking interpolation position, the first coordinate, and the rotation information of the disk includes: determining a third coordinate after the disk rotates based on the first coordinate, the rotation information of the disk, and the time deviation; determining a second coordinate deviation between the third coordinate and the first coordinate; The robot is controlled to track the workpiece position based on the second coordinate deviation.

2. The method for grabbing semiconductor workpieces by disc transport according to claim 1, wherein: Determining whether a semiconductor workpiece exists in the workpiece position is achieved through the following steps: acquiring the image data; Matching the image data with preset image data; If the matching is successful, it is determined that a semiconductor workpiece exists in the workpiece position.

3. The method for grabbing semiconductor workpieces by disc transport according to claim 1, wherein: The rotation information of the disk is obtained based on encoder information of the disk.

4. The method for grabbing semiconductor workpieces by disk transport according to claim 1, wherein: The centers of the workpiece positions on the disc are distributed on a circle with a preset distance as the radius, and the center of the circle is the center of the disc.

5. A robot control system for grabbing a workpiece on a rotating disc, wherein the disc has a plurality of workpiece positions distributed on the disc, and the workpiece positions are used to accommodate semiconductor workpieces to be polished, characterized in that: The robot control system includes a processor configured to: Acquiring image data from an identification area of the disk, wherein the identification area is capable of completely covering at least one workpiece position; In a case where it is determined based on the acquired image data that a semiconductor workpiece exists in the workpiece position, converting the workpiece position to a first coordinate in a reference coordinate system based on the image data; Using the first coordinate as a tracking interpolation position, controlling the manipulator to move to the first coordinate; Controlling the manipulator to track the workpiece position based on the tracking interpolation position, the first coordinate, and the rotation information of the disk; When the polishing time meets the requirement, the semiconductor workpiece is grabbed from the grabbing area of the disk, wherein the grabbing area does not overlap with the identification area. When the polishing is about to be completed, the manipulator is controlled to perform tracking operation and complete the grabbing within one rotation of the disk. The processor is further configured to: determine a second coordinate of the manipulator in the reference coordinate system; determining a first coordinate deviation between the second coordinate and the first coordinate; Based on the first coordinate deviation, controlling the manipulator to move to the first coordinate, and recording the time deviation of the manipulator moving to the first coordinate; The processor is further configured to: determine a third coordinate after the disk rotates based on the first coordinate, the rotation information of the disk, and the time deviation; determining a second coordinate deviation between the third coordinate and the first coordinate; The robot is controlled to track the workpiece position based on the second coordinate deviation.

6. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of the method for grabbing a semiconductor workpiece using a disc transfer according to any one of claims 1 to 4.

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