Laser processing positioning correction method and system, electronic equipment and storage medium

Abstract

The invention discloses a laser processing positioning correction method and system, electronic equipment and a storage medium, and the method comprises the steps: controlling a laser beam to scan a positioning mark on a wafer, and achieving the precise positioning of the laser beam through a monitored signal; synchronously obtaining the absolute coordinates of the laser galvanometer for the positioning mark on the wafer under the precise positioning of the laser beam; in combination with drawing information of a wafer, the coordinates of each chip are superposed on the basis of the absolute coordinates of the laser galvanometer, so that the coordinates of the laser galvanometer corresponding to each chip are obtained. In the subsequent laser machining process, the laser galvanometer can be directly used for controlling the laser beams, traditional coaxial visual positioning or paraxial visual positioning is replaced, direct positioning of the laser beams is achieved, and the laser machining accuracy of the wafer is improved.

Description

Technical Field

[0001] This invention relates to the technical field of wafer laser processing, and in particular to a laser processing positioning correction method. Background Technology

[0002] Laser processing technology, with its high energy density and precise controllability, can achieve micron-level and even nanon-level processing accuracy. During processing, the heat-affected zone is extremely small, the kerf width is narrow, the material removal rate is controllable at the sub-micron level, and the surface roughness Ra value can be better than 0.1 microns. Through CNC systems and galvanometer scanning, positioning accuracy can reach ±2 microns, and repeatability is ±1 micron. It is particularly suitable for the micro-cutting, drilling, and etching of brittle and hard materials, thin films, and composite materials, and is widely used in semiconductor wafer dicing, cardiovascular stent processing, and precision mold manufacturing, making it a key process for achieving high-precision, low-damage micro / nano manufacturing.

[0003] In laser systems, galvanometers are typically used to control the movement of the laser beam, and the laser's coordinates are usually directly represented by the galvanometer coordinates. However, after prolonged use, due to mechanical drift, thermal deformation, and aging of optical components, a misalignment occurs between the galvanometer coordinates and the actual coordinates of the laser spot. If galvanometer coordinates are still used for positioning during laser wafer processing, the laser spot will not be in the expected position, resulting in insufficient processing accuracy. Summary of the Invention

[0004] To improve the laser positioning accuracy during wafer fabrication, this invention provides a laser processing positioning correction method.

[0005] This application provides the following technical solution:

[0006] In a first aspect, this application provides a laser positioning and processing correction method, comprising:

[0007] Obtain the wafer's drawing information, which includes the size information of the positioning marks and the relative coordinate information of each chip and the positioning marks;

[0008] The laser beam is controlled to perform laser movement scanning on the positioning mark in the X and Y directions respectively, and the intensity value of the laser return signal is monitored and acquired in real time.

[0009] Obtain the initial coordinates of the laser galvanometer when the laser beam is at the starting point, and calculate the distance the laser beam moves from the starting point to the central axis of the positioning mark based on the intensity value of the laser return signal.

[0010] Based on the moving distance and the starting coordinates of the laser galvanometer, the absolute coordinates of the laser galvanometer at the absolute origin are calculated, and the actual coordinates of the laser galvanometer during chip processing are determined according to the relative coordinate information. The absolute origin is the intersection of the central axes of the positioning mark in the X and Y directions.

[0011] By employing the above technical solution, the actual position of the laser beam is determined using laser monitoring and scanning. Due to the synchronous movement of the laser beam and the laser galvanometer, the actual moving distance of the laser galvanometer is obtained. Combining the initial coordinates of the laser galvanometer, and setting the coordinates of the laser beam as the absolute origin, the absolute coordinates of the laser galvanometer in the absolute coordinate system are obtained. By superimposing the relative coordinate information of the chip in the wafer drawing file with the absolute coordinates of the laser galvanometer, the accuracy of the laser beam position is obtained when using the laser galvanometer coordinates for control during wafer laser processing, thus ensuring the precision of laser processing.

[0012] Optionally, the step of controlling the laser beam to perform laser movement scanning on the positioning mark in the X and Y directions respectively, and monitoring and acquiring the intensity value of the laser return signal in real time, includes:

[0013] Based on the size information of the positioning marks, the geometric region of the positioning marks is established;

[0014] Move the laser galvanometer coordinates to the center of the geometric region.

[0015] Optionally, the steps of obtaining the initial coordinates of the laser galvanometer when the laser beam is at the starting point, and calculating the distance the laser beam moves from the starting point to the central axis of the positioning mark based on the intensity value of the laser return signal, include:

[0016] Establish the laser return signal intensity value and motion time curve, and select a set time as the starting time of the laser beam;

[0017] Based on the starting time of the laser beam, the starting coordinates of the laser galvanometer are obtained from the laser control system.

[0018] Optionally, the steps of obtaining the initial coordinates of the laser galvanometer when the laser beam is at the starting point, and calculating the distance the laser beam moves from the starting point to the central axis of the positioning mark based on the intensity value of the laser return signal, further include:

[0019] Obtain the start and end times of the sudden change in the intensity value of the laser echo signal, and determine the time when the laser beam is at the midpoint of the central axis of the positioning mark;

[0020] The moving speed of the laser beam is determined based on the size information of the positioning mark;

[0021] The distance the laser beam travels is determined based on the starting time, midpoint time, and moving speed of the laser beam.

[0022] Optionally, the step of determining the moment when the laser beam is at the midpoint of the central axis of the positioning mark, in the process of acquiring the start and end times of the sudden change in the intensity value of the laser return signal, includes:

[0023] Based on the intensity value of the laser return signal and the motion time curve, determine the four moments when the slope of the curve reaches the preset value;

[0024] Based on the chronological order of the four moments, the second moment is selected as the start moment, and the third moment is selected as the end moment.

[0025] Optionally, the step of calculating the absolute coordinates of the laser mirror at the absolute origin based on the moving distance and the initial coordinates of the laser mirror, and determining the actual coordinates of the laser mirror during the processing of each chip based on the relative coordinate information, includes:

[0026] In the X and Y directions, the absolute coordinates of the laser galvanometer are obtained by superimposing the distance the laser beam moves from the starting point to the central axis of the positioning mark and the starting coordinates of the laser galvanometer.

[0027] Optionally, the step of calculating the absolute coordinates of the laser mirror at the absolute origin based on the moving distance and the initial coordinates of the laser mirror, and determining the actual coordinates of the laser mirror during the processing of each chip based on the relative coordinate information, further includes:

[0028] The relative coordinate information is superimposed onto the absolute coordinates of the laser galvanometer to obtain the actual coordinates of the laser galvanometer during the processing of each chip.

[0029] Secondly, this application provides a laser positioning and machining correction system, comprising:

[0030] The information acquisition module is used to acquire wafer drawing information, wherein the drawing information includes positioning mark size information and relative coordinate information of each chip and positioning mark;

[0031] The processing monitoring module is used to control the laser beam to perform laser movement scanning on the positioning mark in the X and Y directions respectively, and to monitor and acquire the intensity value of the laser return signal in real time.

[0032] The data processing module is used to obtain the starting coordinates of the laser galvanometer when the laser beam is at the starting point, and to calculate the moving distance of the laser beam from the starting point to the central axis of the positioning mark based on the intensity value of the laser return signal.

[0033] The coordinate update module is used to calculate the absolute coordinates of the laser galvanometer at the absolute origin based on the moving distance and the starting coordinates of the laser galvanometer, and to determine the actual coordinates of the laser galvanometer during the processing of each chip based on the relative coordinate information. The absolute origin is the intersection of the central axis of the positioning mark in the X and Y directions.

[0034] Thirdly, this application provides an electronic device, including a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, it implements the laser processing positioning correction method as described in any of the above embodiments.

[0035] Fourthly, this application provides a computer-readable storage medium, wherein the computer program, when executed by a processor, implements the laser processing positioning correction method as described in any of the above embodiments.

[0036] In summary, the present invention has at least one of the following beneficial technical effects:

[0037] 1. This solution can directly achieve precise control of the laser spot, and has the characteristics of high precision in laser processing applications.

[0038] 2. This solution replaces traditional coaxial or paraxial vision positioning, achieving direct positioning of the laser beam and resulting in higher control efficiency for laser processing. Attached Figure Description

[0039] Figure 1 This is a schematic flowchart of a laser processing positioning correction method according to an embodiment of this application.

[0040] Figure 2 This is a schematic diagram of laser scanning monitoring in a laser processing positioning correction method according to an embodiment of this application.

[0041] Figure 3 This is a schematic diagram of the laser moving scan process in a laser processing positioning correction method according to an embodiment of this application.

[0042] Figure 4 This is a schematic flowchart illustrating the calculation of the laser beam movement distance in a laser processing positioning correction method according to an embodiment of this application.

[0043] Figure 5 This is a schematic flowchart illustrating the process of determining the moment when the laser beam is at the midpoint of the positioning mark in a laser processing positioning correction method according to an embodiment of this application.

[0044] Figure 6 This is a flowchart illustrating the process of determining the actual coordinates of a laser galvanometer during chip processing in a laser processing positioning correction method according to an embodiment of this application. Detailed Implementation

[0045] The following is in conjunction with the appendix Figure 1 - Appendix Figure 6 This embodiment will be described in further detail.

[0046] Wafer files are critical data files in the semiconductor manufacturing process, commonly used to record and visualize the location, status, and test results of each chip on the wafer. In a wafer file, the coordinates of each chip can be represented using a precise coordinate system.

[0047] Typically, wafers have standardized physical features used for positioning, alignment, and crystal orientation. Commonly used standardized physical features include V-grooves at the wafer edge, straight cut edges, and photolithographic patterns such as crosshairs, squares, and L-shaped right angles on the wafer surface. V-grooves and straight cut edges are usually used to determine the wafer's crystal orientation and rotation angle, facilitating the establishment of a unified global coordinate system. Meanwhile, photolithographic patterns such as crosshairs, squares, and L-shaped right angles on the wafer surface typically serve as dedicated positioning markers, allowing for precise identification and positioning during photolithography, inspection, and dicing processes, acting as reference points for the entire wafer coordinate system.

[0048] Embodiment 1 of this invention discloses a laser processing positioning correction method. (Refer to...) Figure 1 and Figure 2 The methods include:

[0049] S1. Obtain the wafer's drawing information.

[0050] The wafer drawing information is usually provided by the wafer manufacturer. The wafer drawing contains a variety of information, such as metadata such as wafer number, wafer size, manufacturer, and production date; chip layout information, such as the length and width of the chip, the chip number, and the physical coordinates of the chip on the wafer; and some standardized physical features on the wafer, such as notches, chamfers, the shape of special positioning marks, their position on the wafer, and the size information of the positioning marks themselves.

[0051] The dedicated positioning marks on the wafer serve as reference points for the absolute coordinate system, enabling the establishment of a unified coordinate system on the wafer and ensuring that each chip has a unique coordinate value. In this embodiment, the dedicated positioning marks are L-shaped right-angled patterns, and the intersection of the central axes of the two rectangles in the width direction of the L-shaped right-angled pattern is the origin of the coordinate system, thereby obtaining the absolute coordinate system of the corresponding wafer and thus obtaining more refined coordinate values ​​for each chip.

[0052] S2. Control the laser beam to perform laser movement scanning on the positioning mark in the X and Y directions respectively, and monitor and obtain the intensity value of the laser return signal in real time.

[0053] The laser beam's movement and scanning are controlled by a laser motion control system, which moves the laser beam by controlling the tilt of the laser galvanometer. A beam splitter and a detector are added to the laser optical path. The original laser beam emitted by the laser passes through the beam splitter and laser galvanometer before reaching the laser processing plane. The reflected light signal from the laser processing plane passes through the laser galvanometer and beam splitter again before entering the detector, thus enabling the monitoring of the intensity value of the reflected laser light signal.

[0054] Because of the high cleanliness of the wafer surface, the laser beam exhibits a relatively stable return signal during its scanning motion. However, the positioning marks are obtained through photolithography or deposition on the wafer surface, resulting in a high-contrast geometry between the positioning marks and the wafer surface. After the laser beam moves to the positioning mark on the wafer surface, the change in height causes significant fluctuations in the laser return signal. By monitoring the intensity of the laser return signal, it is possible to clearly determine whether the laser beam's scanning trajectory has passed the positioning mark.

[0055] Reference Figure 2 and Figure 3 In step S2, the following is also included:

[0056] S21. Obtain the size information of the positioning marks based on the wafer drawing file, and establish the geometric region of the positioning marks.

[0057] The size information of the positioning mark includes its length and width. The length and width of the positioning mark are used to determine the size of the geometric area on the wafer surface occupied by the positioning mark. In this embodiment, the positioning mark is an L-shaped right-angled pattern. Therefore, the geometric area is the area of ​​the rectangle circumscribed by the L-shaped right-angled pattern.

[0058] S22. Move the laser galvanometer coordinates to the center of the geometric region.

[0059] The laser galvanometer coordinates rely on the mechanical coordinate system, which is the coordinate system in which the entire laser system / equipment exists. Within this coordinate system, all relevant hardware in the laser processing system has a precise position, such as the laser galvanometer position and the wafer position. Furthermore, before wafer processing, the wafer stage can be adjusted using the mechanical coordinate system, thereby achieving preliminary wafer positioning.

[0060] In this embodiment, the wafer position is adjusted by the wafer stage so that the two long sides of the L-shaped positioning mark are aligned with the X and Y axes, respectively. Furthermore, the laser galvanometer coordinates are moved to the geometric area of ​​the L-shaped positioning mark to quickly scan the L-shaped positioning mark in the X and Y directions using a laser, without frequently controlling the laser galvanometer to move to another location for scanning in the other direction. In this embodiment, the laser galvanometer coordinates are set to the center of the geometric area so that the laser galvanometer can be directly moved within the geometric area.

[0061] S3. Obtain the starting coordinates of the laser galvanometer when the laser beam is at the starting point, and calculate the distance the laser beam moves from the starting point to the central axis of the positioning mark based on the intensity value of the laser return signal.

[0062] During the laser-driven scanning and positioning of the positioning mark, the high contrast between the mark and the wafer surface causes significant changes in the intensity of the monitored laser return signal. Even if there is an offset between the coordinates of the laser beam and the laser galvanometer, in this embodiment, the actual position of the laser beam can be directly indicated using the laser return signal.

[0063] In addition, the starting coordinates of the laser galvanometer when the laser beam is at the starting point can be the point in the geometric region where the laser galvanometer moves to the L-shaped positioning mark, the stationary position of the laser galvanometer when it is stationary, or the real-time coordinate position of the laser galvanometer at a certain moment during the moving scanning process.

[0064] Reference Figure 1 , Figure 2 and Figure 4 In step S3, the following is included:

[0065] S31. Establish the laser return signal intensity value and motion time curve, and select a set time as the starting time of the laser beam.

[0066] When the laser system begins its moving scan, the laser galvanometer continuously moves in one direction, and the detector continuously monitors and records the intensity of the laser echo signal. Based on the movement time and the intensity of the laser echo signal, a curve showing the intensity of the laser echo signal versus the movement time can be established.

[0067] The laser galvanometer begins its scanning motion near the center of the geometric region marked by the L-shaped positioning mark. By combining this information with the dimensions of the L-shaped positioning mark, the distance the laser galvanometer travels across the wafer surface in the X or Y direction can be determined. Furthermore, by incorporating the laser galvanometer's operating motion parameters, i.e., its operating speed, the approximate time range before the laser galvanometer reaches the L-shaped positioning mark on the wafer surface can be calculated. A point within this time range can then be selected as the starting point of the laser beam; a more optimal choice is to select the midpoint of this time range.

[0068] In this embodiment, time t0, when the curve is in a stable state after the laser galvanometer starts moving, is selected as the starting time of the laser beam. The starting coordinates of the laser galvanometer are the real-time coordinates of the laser galvanometer at time t0 during the moving scan process. By selecting the real-time coordinates at time t0 in the moving state as the starting coordinates, the influence of the acceleration process of the laser galvanometer in the early stage of movement can be eliminated, resulting in higher accuracy of coordinate recognition and positioning in high-precision motion processing.

[0069] S32. Based on the starting time of the laser beam, obtain the starting coordinates of the laser galvanometer from the laser control system.

[0070] The intensity of the laser return signal is monitored in real time by a detector in the laser optical path system. Furthermore, the movement of the laser beam and the laser galvanometer are synchronized. The laser control system stores the real-time coordinate data of the laser galvanometer. After determining the starting moment of the laser beam, the actual coordinates of the laser galvanometer at that moment can be read through the laser control system; these are the starting coordinates of the laser galvanometer.

[0071] S33. Obtain the start and end times of the sudden change in the intensity value of the laser return signal, and determine the time when the laser beam is at the midpoint of the positioning mark.

[0072] During the scanning process, the laser beam sequentially passes over the surface of the wafer and the L-shaped positioning mark. Therefore, the intensity of the laser return signal will change abruptly. By using the start and end times of these abrupt changes in intensity, we can determine the times when the laser beam arrives at and leaves the L-shaped positioning mark, thus identifying the midpoint of the laser beam on the positioning mark. In this embodiment, t1 and t2 are the start and end times of the signal abrupt change as the laser beam scans and moves past the positioning mark. Therefore, the midpoint of the laser beam on the positioning mark is (t1 + t2) / 2.

[0073] Reference Figure 2 and Figure 5 In step S33, the following is included:

[0074] S331. Based on the intensity value of the laser return signal and the motion time curve, determine the four times when the slope of the curve reaches the preset value.

[0075] S332. Based on the order of the four moments, select the second moment as the start moment and the third moment as the end moment.

[0076] The laser scanning trajectory is a straight line, typically formed by overlapping laser spots. When the laser spot passes the boundary between the wafer surface and the L-shaped positioning mark, different spot overlap rates and varying laser mirror movement speeds result in abrupt changes in the intensity of the monitored laser return signal. In this case, the entire signal abrupt change process produces four distinct moments. Therefore, for applications requiring higher accuracy, when identifying the start and end moments of the signal intensity abrupt change, the slope of the curve can be used to select two adjacent moments as the start and end moments, allowing for more precise identification of when the laser beam arrives at and leaves the L-shaped positioning mark.

[0077] S34. Determine the moving speed of the laser beam based on the size information of the positioning mark.

[0078] The coordinates of the laser beam and the coordinates of the laser galvanometer move synchronously. When determining the moving speed of the laser beam, the motion parameters of the laser galvanometer can be obtained directly, or the moving speed of the laser beam can be determined directly by using the velocity-displacement formula based on the time it takes for the laser beam to pass through the L-shaped positioning mark.

[0079] Specifically, if the moving speed of the laser beam is determined by the velocity-displacement formula, the speed can be obtained by monitoring the moments t1 and t2 when the signal changes abruptly, as well as the trajectory displacement W of the laser beam scanning and moving on the positioning mark, which is W / (t2-t1).

[0080] S35. Determine the distance the laser beam travels based on the starting time, midpoint time, and moving speed of the laser beam.

[0081] Similarly, the starting time of the laser beam is selected during the stable motion of the laser galvanometer. Then, in the X or Y direction, the distance the laser beam travels from the starting time to the central axis of the L-shaped positioning mark can be determined using the velocity-time formula.

[0082] Specifically, the laser beam reaches the midpoint of the positioning mark at time (t1+t2) / 2, starts at time t0, and has a speed of W / (t2-t1). Therefore, the distance the laser beam moves is W / (t2-t1)*((t1+t2) / 2-t0).

[0083] S4. Based on the moving distance and the starting coordinates of the laser galvanometer, calculate the absolute coordinates of the laser galvanometer at the absolute origin of the laser beam, and determine the actual coordinates of the laser galvanometer during the processing of each chip based on the relative coordinate information.

[0084] The absolute origin is the intersection of the central axes of the positioning mark in the X and Y directions. Since the laser beam and laser galvanometer move synchronously, as the laser beam moves from its starting position in the X and Y directions to the corresponding central axis of the positioning mark, the laser galvanometer also moves synchronously from its starting coordinates to a specific position in the corresponding direction. The coordinates of the laser galvanometer when the laser beam is at the absolute origin are obtained by measuring the distances moved in the X and Y directions; these are the absolute coordinates of the laser galvanometer. Combining these with the relative coordinates of each chip and the positioning mark, the actual coordinates of the laser galvanometer before processing of each chip are obtained.

[0085] Reference Figure 1 and Figure 6 In step S4, the following is included:

[0086] S41. In the X and Y directions, the distance the laser beam moves from the starting point to the central axis of the positioning mark and the starting coordinates of the laser galvanometer are superimposed to obtain the absolute coordinates of the laser galvanometer.

[0087] S42. Superimpose the relative coordinate information onto the absolute coordinates of the laser galvanometer to obtain the actual coordinates of the laser galvanometer during the processing of each chip.

[0088] The actual coordinates of the laser galvanometer corresponding to each chip can be obtained by superimposing the relative coordinates between each chip and the positioning mark in the wafer image with the absolute coordinates of the laser galvanometer. During subsequent laser processing, control can be directly achieved using these laser galvanometer coordinates, eliminating the need for further calibration of the laser galvanometer and laser beam coordinates.

[0089] The implementation principle of this embodiment is as follows: A laser beam is controlled to scan the positioning marks on the wafer. Precise positioning of the laser beam is achieved using monitored signals, and simultaneously, the absolute coordinates of the laser mirror relative to the positioning marks on the wafer are obtained under this precise laser beam positioning. Combining the wafer's drawing information, the coordinates of each chip are superimposed on the absolute coordinates of the laser mirror, thus obtaining the laser mirror coordinates corresponding to each chip. In subsequent laser processing, the laser mirror can be directly used to control the laser beam, replacing traditional coaxial or paraxial vision positioning, achieving direct laser beam positioning and improving the accuracy of wafer laser processing.

[0090] Embodiment 2 of the present invention discloses a laser processing positioning correction system, the system comprising:

[0091] The information acquisition module is used to acquire wafer drawing information, wherein the drawing information includes positioning mark size information and relative coordinate information of each chip and positioning mark;

[0092] The processing monitoring module is used to control the laser beam to perform laser movement scanning on the positioning mark in the X and Y directions respectively, and to monitor and acquire the intensity value of the laser return signal in real time.

[0093] The data processing module is used to obtain the starting coordinates of the laser galvanometer when the laser beam is at the starting point, and to calculate the moving distance of the laser beam from the starting point to the central axis of the positioning mark based on the intensity value of the laser return signal.

[0094] The coordinate update module is used to calculate the absolute coordinates of the laser galvanometer at the absolute origin based on the moving distance and the starting coordinates of the laser galvanometer, and to determine the actual coordinates of the laser galvanometer during the processing of each chip based on the relative coordinate information. The absolute origin is the intersection of the central axis of the positioning mark in the X and Y directions.

[0095] The laser processing positioning correction system provided in this embodiment controls a laser beam to scan positioning marks on a wafer. It uses monitored signals to achieve precise laser beam positioning and simultaneously obtains the absolute coordinates of the laser mirror relative to the positioning marks on the wafer under precise laser beam positioning. Combining this with the wafer's drawing information, the coordinates of each chip are superimposed on the absolute coordinates of the laser mirror to obtain the laser mirror coordinates corresponding to each chip. In subsequent laser processing, the laser beam can be directly controlled using the laser mirror, eliminating the need for complex optical path correction of the laser system and improving the accuracy of wafer laser processing.

[0096] Furthermore, this invention also discloses an electronic device, including a memory and a processor. The memory stores a computer program, and when the computer program is executed by the processor, it implements the laser processing positioning correction method of Embodiment 1.

[0097] This invention provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the laser processing positioning correction method of Embodiment 1.

[0098] In this embodiment, the computer-readable storage medium may be a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, etc.

[0099] The computer-readable storage medium provided in this embodiment can implement the laser processing positioning correction method provided in Embodiment 1. To avoid repetition, it will not be described again here.

[0100] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A laser processing positioning correction method, characterized in that, include: Obtain the wafer's drawing information, which includes the size information of the positioning marks and the relative coordinate information of each chip and the positioning marks; The laser beam is controlled to perform laser movement scanning on the positioning mark in the X and Y directions respectively, and the intensity value of the laser return signal is monitored and acquired in real time. Obtain the initial coordinates of the laser galvanometer when the laser beam is at the starting point, and calculate the distance the laser beam moves from the starting point to the central axis of the positioning mark based on the intensity value of the laser return signal. Based on the moving distance and the starting coordinates of the laser galvanometer, the absolute coordinates of the laser galvanometer at the absolute origin are calculated, and the actual coordinates of the laser galvanometer during chip processing are determined according to the relative coordinate information. The absolute origin is the intersection of the central axes of the positioning mark in the X and Y directions.

2. The laser processing positioning correction method according to claim 1, characterized in that: The steps of controlling the laser beam to perform laser movement scanning of the positioning mark in the X and Y directions respectively, and monitoring and acquiring the intensity value of the laser return signal in real time, include: Based on the size information of the positioning marks, the geometric region of the positioning marks is established; Move the laser galvanometer coordinates to the center of the geometric region.

3. The laser processing positioning correction method according to claim 1, characterized in that: The steps of obtaining the initial coordinates of the laser galvanometer when the laser beam is at the starting point, and calculating the distance the laser beam moves from the starting point to the central axis of the positioning mark based on the intensity value of the laser return signal, include: Establish the laser return signal intensity value and motion time curve, and select a set time as the starting time of the laser beam; Based on the starting time of the laser beam, the starting coordinates of the laser galvanometer are obtained from the laser control system.

4. The laser processing positioning correction method according to claim 3, characterized in that: The steps of obtaining the initial coordinates of the laser galvanometer when the laser beam is at the starting point, and calculating the distance the laser beam moves from the starting point to the central axis of the positioning mark based on the intensity value of the laser return signal, also include: Obtain the start and end times of the sudden change in the intensity value of the laser echo signal, and determine the time when the laser beam is at the midpoint of the central axis of the positioning mark; The moving speed of the laser beam is determined based on the size information of the positioning mark; The distance the laser beam travels is determined based on the starting time, midpoint time, and moving speed of the laser beam.

5. The laser processing positioning correction method according to claim 4, characterized in that: The steps of determining the moment when the laser beam is at the midpoint of the central axis of the positioning mark, in order to obtain the start and end times of the sudden change in the intensity value of the laser return signal, include: Based on the intensity value of the laser return signal and the motion time curve, determine the four moments when the slope of the curve reaches the preset value; Based on the chronological order of the four moments, the second moment is selected as the start moment, and the third moment is selected as the end moment.

6. The laser processing positioning correction method according to claim 1, characterized in that: The steps of calculating the absolute coordinates of the laser mirror at the absolute origin based on the moving distance and the initial coordinates of the laser mirror, and determining the actual coordinates of the laser mirror during the processing of each chip based on the relative coordinate information, include: In the X and Y directions, the absolute coordinates of the laser galvanometer are obtained by superimposing the distance the laser beam moves from the starting point to the central axis of the positioning mark and the starting coordinates of the laser galvanometer.

7. The laser processing positioning correction method according to claim 1, characterized in that: The steps of calculating the absolute coordinates of the laser mirror at the absolute origin based on the moving distance and the initial coordinates of the laser mirror, and determining the actual coordinates of the laser mirror during the processing of each chip based on the relative coordinate information, also include: The relative coordinate information is superimposed onto the absolute coordinates of the laser galvanometer to obtain the actual coordinates of the laser galvanometer during the processing of each chip.

8. A laser processing positioning correction system, characterized in that, include: The information acquisition module is used to acquire wafer drawing information, wherein the drawing information includes positioning mark size information and relative coordinate information of each chip and positioning mark; The processing monitoring module is used to control the laser beam to perform laser movement scanning on the positioning mark in the X and Y directions respectively, and to monitor and acquire the intensity value of the laser return signal in real time. The data processing module is used to obtain the starting coordinates of the laser galvanometer when the laser beam is at the starting point, and to calculate the moving distance of the laser beam from the starting point to the central axis of the positioning mark based on the intensity value of the laser return signal. The coordinate update module is used to calculate the absolute coordinates of the laser galvanometer at the absolute origin based on the moving distance and the starting coordinates of the laser galvanometer, and to determine the actual coordinates of the laser galvanometer during the processing of each chip based on the relative coordinate information. The absolute origin is the intersection of the central axis of the positioning mark in the X and Y directions.

9. An electronic device, characterized in that, It includes a memory and a processor, wherein the memory stores a computer program that, when executed by the processor, implements the laser processing positioning correction method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, It stores a computer program, which, when executed by a processor, implements the laser processing positioning correction method as described in any one of claims 1 to 7.

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