Laser processing system and method

Abstract

The invention discloses a laser processing system and a laser processing method, which are used for carrying out surface treatment on a wafer. The laser processing system comprises a pulse laser device, a space optical modulator, a scanning mirror group, an optical sensing element and an arithmetic device. The space optical modulator is arranged on the output path of the pulse laser device and used for generating a diffraction pattern to modulate a light spot shape formed by the laser beam on the surface of the wafer. The scanning mirror set is used for being controlled to guide the light spot shape of the laser beam at a scanning angle to conduct machining along the machining track in the machining area of the surface of the wafer. The optical sensing element is used for obtaining a feedback light signal from the processing area to generate an image. And the arithmetic device is used for controlling the space optical modulator to generate the diffraction pattern according to the chromaticity data of the image and controlling the scanning mirror group to scan at the scanning angle.

Description

Technical Field

[0001] This invention relates to a laser processing system and method. Background Technology

[0002] Driven by increasing demand from industries such as solar energy, consumer electronics, and electric vehicles, the silicon wafer recycling market is projected to grow at a CAGR of 16.4% from 2023 to 2031. The increasing recycling rate of silicon sources in the consumer electronics sector is a key driver of this market growth. Furthermore, advancements in consumer electronics, including artificial intelligence (AI) and the Internet of Things (IoT), and the growing prevalence of smartphones, computers, and other consumer electronics products, are also significant factors contributing to the demand for silicon wafer recycling.

[0003] In current manufacturing processes, existing etching and demolding processes are not in line with future green manufacturing trends. In particular, chemical acid etching processes generate waste liquid and consume a large amount of water. For example, the average water consumption for 6-inch, 8-inch, and 12-inch wafers is approximately 0.79 tons / wafer, 4 tons / wafer, and 7.3 tons / wafer, respectively. Summary of the Invention

[0004] In view of the above, the present invention provides a laser processing system and method.

[0005] A laser processing system according to an embodiment of the present invention is used for surface treatment of a wafer. The laser processing system includes a pulsed laser device, a spatial optical modulator, a scanning mirror assembly, an optical sensing element, and a computing device. The pulsed laser device outputs a laser beam. The spatial optical modulator is disposed in the output path of the laser beam and is used to generate a diffraction pattern to modulate a spot shape formed by the laser beam on the wafer surface. The scanning mirror assembly is disposed in the output path of the laser beam and is controlled to guide the spot shape of the laser beam along a processing trajectory within a processing area on the wafer surface at a scanning angle. The optical sensing element is used to acquire a feedback light signal from the processing area on the wafer surface to generate an image, wherein the transmission path of the feedback light signal is at least partially parallel or coaxial with the output path of the laser beam. The computing device is connected to the spatial optical modulator, the optical sensing element, and the scanning mirror assembly, and is used to control the spatial optical modulator to generate the diffraction pattern and control the scanning mirror assembly to scan at the scanning angle based on chromaticity data of the image.

[0006] A laser processing method according to an embodiment of the present invention is used to perform surface treatment on a wafer using a pulsed laser device, comprising: providing a laser processing system including a pulsed laser device, a spatial optical modulator, a scanning mirror assembly, an optical sensing element, and a computing device, wherein the optical sensing element is used to acquire a feedback light signal from a processing area on the wafer surface, and the transmission path of the feedback light signal is at least partially parallel or coaxial with the output path of the laser beam; and the computing device performs: acquiring an image of a processing area on the wafer surface through the optical sensing element, wherein the image is generated based on a feedback light signal from the processing area on the wafer surface; controlling a spatial optical modulator to generate a diffraction pattern based on chromaticity data of the image to modulate a spot shape formed on the wafer surface by a laser beam output by the pulsed laser device; and controlling a scanning mirror assembly to guide the spot shape of the laser beam along a processing trajectory within the processing area on the wafer surface at a scanning angle based on the chromaticity data.

[0007] Through the aforementioned structure, the laser processing system and method disclosed in this case acquire an image of the current processing area on the wafer surface using an optical architecture that is at least partially coaxial or parallel to the laser beam. Based on the chromaticity data of the image, a spatial optical modulator is used to modulate the shape of a spot formed by the laser beam on the wafer surface. Furthermore, based on the chromaticity data, a scanning mirror assembly guides the laser beam's processing trajectory on the wafer surface. This allows for real-time monitoring of the surface material in different areas of the wafer surface and switching between specific spot shapes and scanning paths for continuous processing, achieving efficient removal of various surface materials from the wafer. Moreover, it can be performed without the use of traditional chemical wet etching solutions, saving water resources and avoiding environmental pollution.

[0008] The above description of the content of this invention and the following description of the embodiments are intended to demonstrate and explain the spirit and principles of this invention, and to provide a further explanation of the scope of this patent application. Attached Figure Description

[0009] Figure 1 This is a block diagram illustrating a laser processing system according to an embodiment of the present invention;

[0010] Figure 2 This is a schematic diagram of the optical path of a laser processing system according to an embodiment of the present invention;

[0011] Figure 3 This is a flowchart illustrating a laser processing method according to an embodiment of the present invention;

[0012] Figure 4 This is a schematic diagram illustrating a hexagonal crystal lattice and its corresponding two-dimensional processing profile according to an embodiment of the present invention.

[0013] Figure 5 for Figure 4 A schematic diagram illustrating the spot shape and processing trajectory in the embodiment;

[0014] Figure 6 This is a schematic diagram illustrating the rhombohedral crystal lattice and the corresponding two-dimensional processing profile according to an embodiment of the present invention;

[0015] Figure 7 for Figure 6 A schematic diagram illustrating the shape of the light spot and the processing trajectory in the embodiment.

[0016] Symbol Explanation

[0017] 1: Laser processing system

[0018] 11: Pulsed laser device

[0019] 12: Spatial Optical Modulator

[0020] 13: Scanning mirror assembly

[0021] 14: Optical sensing element

[0022] 15: Computing device

[0023] 16-1, 16-2: Beam Spectroscope

[0024] 17-1, 17-2, 17-3, 17-4, 17-5: Lenses

[0025] L: Laser beam

[0026] F: Feedback light signal

[0027] 2: Wafer

[0028] S1-S5: Steps

[0029] CL: Crystal Lattice

[0030] C: Two-dimensional contour

[0031] T: Processing trajectory

[0032] SP: Light Spot Detailed Implementation

[0033] The following detailed description of the features and advantages of the present invention in the embodiments is sufficient to enable anyone skilled in the art to understand the technical content of the present invention and implement it accordingly. Based on the disclosure, claims, and drawings in this specification, anyone skilled in the art can easily understand the related objectives and advantages of the present invention. The following embodiments are intended to further illustrate the points of the present invention, but are not intended to limit the scope of the present invention in any way.

[0034] Figure 1 This is a block diagram of a laser processing system according to an embodiment of the present invention. Figure 1 As shown, the laser processing system 1 includes a pulsed laser device 11, a spatial optical modulator 12, a scanning mirror assembly 13, an optical sensing element 14, and a computing unit 15. The pulsed laser device 11 outputs a laser beam L. The spatial optical modulator 12 is disposed in the output path of the laser beam L and is used to generate a diffraction pattern to modulate the shape of a spot formed by the laser beam L on the surface of the wafer 2. The scanning mirror assembly 13 is disposed in the output path of the laser beam L and is used to guide the spot shape of the laser beam L along a processing trajectory within a processing area on the wafer surface at a controlled scanning angle. The optical sensing element 14 acquires a feedback light signal F from the processing area on the wafer surface to generate an image, wherein the transmission path of the feedback light signal F is at least partially parallel or coaxial with the output path of the laser beam L. The computing device 15 is connected to the spatial optical modulator 12, the scanning lens group 13 and the optical sensing element 14 via wired or wireless means, and is used to control the spatial optical modulator 12 to generate the diffraction pattern and control the scanning lens group 13 to scan at the scanning angle according to the chromaticity data of the image.

[0035] In this embodiment, the pulsed laser device 11 can set the pulse parameters of its output laser beam according to the application context (e.g., the surface material characteristics of the workpiece). These pulse parameters may include pulse width, repetition rate, pulse energy, peak intensity, etc. For example, the energy of a single pulse may be 100 microjoules (μJ), the pulse width may be 100 nanoseconds (ns), and the repetition rate may be 200 to 400 kilohertz (kHz). Additionally, the pulsed laser device 11 can also select a suitable wavelength range based on the surface material characteristics of the workpiece. The spatial optical modulator 12 can be used to generate a diffraction pattern to modulate the phase distribution of the wavefront of the laser beam L, causing the laser beam L to diffract and form a spot shape on the surface of the wafer 2. For example, the spatial optical modulator 12 may include a liquid crystal display, and the diffraction pattern can be generated based on the Fourier transform result of the desired spot shape, which will be further explained later. Specifically, the spatial optical modulator 12 diffracts the laser beam L through a diffraction pattern, but is not limited to implementation with a specific optical architecture. For example, if the spatial optical modulator 12 is a transmission diffraction device, it can generate a diffraction pattern and allow the laser beam L to pass through the diffraction pattern to produce a specific spot shape; or, the spatial optical modulator 12 can generate a reflection diffraction pattern, allowing the laser beam L to be reflected by the diffraction pattern to produce a specific spot shape.

[0036] The scanning mirror assembly 13 may include an X-mirror, a Y-mirror, and a mirror assembly controller. The mirror assembly controller is connected to the X-mirror and the Y-mirror and is used to control the scanning angles of the X-mirror and the Y-mirror to adjust the processing trajectory of the laser beam L on the wafer surface. For example, after the laser beam L passes through the spatial optical modulator 12, it is guided by the scanning mirror assembly 13 to move along the processing trajectory on the wafer surface (e.g., the scanning speed can be 2000 to 4000 mm / s), so that the spot shape generated by the spatial optical modulator 12 is processed along the processing trajectory on the wafer surface. That is, the laser beam L must first pass through the spatial optical modulator 12 and then through the scanning mirror assembly 13.

[0037] The optical sensing element 14 can be an image capturing device, such as a charge-coupled device (CCD). The optical sensing element 14 is used to acquire a feedback light signal F from the processing area on the wafer surface to generate an image, wherein the transmission path of the feedback light signal F is at least partially parallel or coaxial with the output path of the laser beam L. Figure 1 As shown, the laser beam L can form a processing trajectory on the processing area on the surface of the wafer 2 through the scanning mirror group 12, and the feedback light signal F can be transmitted from the processing area on the surface of the wafer 2 through the scanning mirror group 13 to the optical sensing element 14. In this configuration, since the transmission path of the feedback light signal F is at least partially parallel or coaxial with the output path of the laser beam L, the optical sensing element 14 can obtain a real-time image of the processing area, that is, the optical sensing element 14 can obtain an image of the area on the wafer surface currently being processed by the laser beam L. In addition, the relative position between the optical sensing element 14 and the scanning mirror group 13 is not limited to this. For example, the transmission path of the feedback light signal F may also reach the optical sensing element 14 without passing through the scanning mirror group 13, but the transmission path of the feedback light signal F can still be at least partially parallel or coaxial with the output path of the laser beam L through optical path design.

[0038] The computing device 15 may include one or more processing / control units with data receiving, recording, processing, storage, and output functions. These processing / control units may be, for example, microcontrollers, central processing units, graphics processors, programmable logic controllers, or any combination thereof. The computing device 15 is connected to the spatial optical modulator 12, the scanning mirror assembly 13, and the optical sensing element 14. It acquires the image from the optical sensing element 14 and controls the spatial optical modulator 12 to generate the diffraction pattern and determine the scanning angle of the scanning mirror assembly 13 based on chromaticity data of the image. Specifically, the chromaticity data may include chromaticity coordinates (R, G, B). That is, the computing device 15 can provide feedback control to the spatial optical modulator 12 and the scanning mirror assembly 13 based on the chromaticity of the image of the current processing area of ​​the wafer surface acquired by the optical sensing element 14, thereby optimizing the wafer surface processing fabrication process.

[0039] For optical path configuration, you can refer to... Figure 2 Configuration, Figure 2 This is a schematic diagram of the optical path of a laser processing system according to an embodiment of the present invention. Figure 2 As shown, the laser beam emitted by the pulsed laser device 11 can be shaped by a lens group. For example, lens 17-1 can be used to collimate the laser beam for use by subsequent optical components. The first beam splitter 16-1 can be used to separate the collimated laser beam into a transmitted beam and a reflected beam. There are many types of first beam splitters 16-1, and users can choose according to actual application requirements. For example, users can determine the appropriate first beam splitter 16-1 based on the energy ratio and polarization state between the transmitted and reflected beams. Spatial optical modulator 12. The spatial optical modulator 12 can be a liquid crystal display and can generate a diffraction pattern to modulate the wavefront phase distribution of the laser beam, so that the laser beam forms a specific spot shape on the wafer surface. Lenses 17-2, 17-3, and 17-4 are a lens group with Fourier transform function, used to form the specific spot shape on the surface of wafer 2 after the laser beam with the adjusted wavefront phase distribution is Fourier transformed, and has a focusing effect. For example, the focused diameter of each light spot in the generated light spot shape can be 1 micrometer (μm), and a single light spot can achieve a density of 1.3 × 10⁻⁶ per square centimeter. 11 Watt (W / cm) 2 The power density of ).

[0040] Furthermore, lenses 17-2, 17-3, 17-4, and 17-5 also have imaging capabilities, allowing the feedback light signal from the processing area on the wafer surface to be transmitted to the optical sensing element 14 via the reflection path of lenses 17-2, 17-3, 17-4, and 17-5 and the second beam splitter 16-2. In this embodiment, the laser processing system may further include a second beam splitter 16-2, disposed between the wafer 2 and the optical sensing element 15, and used to guide the feedback light signal to the optical sensing element 14. That is, the second beam splitter 16-2 may be disposed at a bifurcation point between the transmission path of the feedback light signal and the output path of the laser beam. Thus, the transmission path of the feedback light signal and the output path of the laser beam may be at least partially parallel or coaxial. When the optical sensing element 14 receives the feedback light signal and generates a corresponding image, the computing device 15 can perform feedback control on the spatial optical modulator 12 based on the chromaticity data of the image to generate the diffraction pattern, and simultaneously perform feedback control on the scanning mirror assembly to guide the laser beam's processing trajectory on the wafer surface. It should be noted that although the scanning mirror assembly is not shown in this figure, it can be positioned at a specific location in the optical path depending on experimental conditions. For example, the scanning mirror assembly can be positioned after the second beam splitter 16-2 (i.e., the optical sensing element 15 and the second beam splitter 16-2 can be positioned before the scanning mirror assembly), or between the first beam splitter 16-1 and the second beam splitter 16-2, or before the first beam splitter 16-1.

[0041] Please combine Figure 1 , Figure 2 refer to Figure 3 , Figure 3 This is a flowchart illustrating a laser processing method according to an embodiment of the present invention. Figure 3 As shown, a laser processing method for surface treatment of a wafer using a pulsed laser device may include providing a laser processing system as described above, comprising a pulsed laser device, a spatial optical modulator, a scanning mirror assembly, an optical sensing element, and a computing device. The optical sensing element is used to acquire a feedback light signal from a processing area on the wafer surface, and the transmission path of the feedback light signal is at least partially parallel or coaxial with the output path of the laser beam. Furthermore, the computing device performs the following steps: step S1: acquiring an image of a processing area on the wafer surface using the optical sensing element; step S3: controlling the spatial optical modulator to generate a diffraction pattern based on chromaticity data of the image to modulate the shape of a spot formed by the laser beam on the wafer surface; and step S5: controlling the scanning mirror assembly to guide the spot shape of the laser beam along a processing trajectory of the processing area on the wafer surface at a scanning angle based on the chromaticity data.

[0042] In step S1, the computing device 15 can acquire a feedback light signal from the processing area on the wafer surface via the optical sensing element 14 to generate the image, wherein the transmission path of the feedback light signal and the output path of the laser beam can be at least partially parallel or coaxial. In step S3, the computing device 15 can determine a specified spot shape based on the chromaticity data of the image (e.g., the average chromaticity of all pixels in the image), and use the Fourier transform result of this specified spot shape as the diffraction pattern data to control the spatial optical modulator to generate the diffraction pattern to modulate the laser beam to form a spot shape on the wafer surface corresponding to the specified spot shape. In step S5, the computing device 15 can determine a specified processing trajectory based on the chromaticity data, generate the scanning angle of the scanning mirror group 13 based on this specified processing trajectory, and control the scanning mirror group 13 to guide the spot shape of the laser beam along a processing trajectory of the processing area on the wafer surface at the scanning angle, wherein the processing trajectory corresponds to the specified processing trajectory. The specified light spot shape includes multiple light points corresponding to a polygonal outline, and the specified processing trajectory is to process sequentially along the polygonal outline.

[0043] Furthermore, the computing device 15 can determine a surface material within the processing area of ​​the wafer surface based on the chromaticity data and a pre-stored material-surface chromaticity relationship, and determine the specified spot shape and the specified processing trajectory based on the crystal structure of the surface material. For example, the pre-stored material in the material-surface chromaticity relationship may include at least one of silicon dioxide, a high-k dielectric material, and a low-k dielectric material, wherein the high-k dielectric material and the low-k dielectric material are compared based on the dielectric constant of silicon dioxide. That is, the computing device 15 can determine whether the surface material of the current processing area of ​​the wafer surface belongs to silicon dioxide, a high-k dielectric material, or a low-k dielectric material based on the acquired chromaticity data, and then determine the specified spot shape and the specified processing trajectory based on the crystal structure of the surface material. In current semiconductor manufacturing processes, the high-k dielectric material or the low-k dielectric material may specifically include silicon nitride (Si3N4) or polysilicon.

[0044] For details on how the lattice structure of the material on the wafer surface determines the specified spot shape and the specified processing trajectory, please refer to [reference needed]. Figures 4 to 7 , Figure 4 It is a hexagonal crystal lattice and corresponding two-dimensional processing profile illustrated according to an embodiment of the present invention. Figure 5 It is based on Figure 4 A schematic diagram illustrating the shape of the light spot and the processing trajectory in the embodiment. Figure 6 It is a rhombohedral crystal lattice and its corresponding two-dimensional processing profile drawn according to an embodiment of the present invention. Figure 7 It is based on Figure 6 A schematic diagram illustrating the shape of the light spot and the processing trajectory in the embodiment.

[0045] When the computing device determines that the crystal structure of the surface material belongs to the hexagonal crystal system, it can decide that the specified light spot shape is multiple light spots corresponding to an octagonal contour, and the specified processing trajectory is to process sequentially along this octagonal contour. For example... Figure 4 As shown, the computing device can determine the crystal structure corresponding to the surface material based on the aforementioned chromaticity data. In this embodiment, the crystal lattice CL belongs to the hexagonal crystal system (e.g., silicon dioxide, silicon nitride). In this case, the computing device can generate a two-dimensional profile C with multiple closely arranged octagons. Next, as... Figure 5 As shown, the computing device can determine that the specified spot shape is a plurality of light spots SP corresponding to an octagonal contour, and the specified processing trajectory is a processing trajectory T sequentially performed along this octagonal contour. Specifically, based on a two-dimensional contour with a lattice structure (e.g., an octagonal contour), the way the plurality of light spots SP and the processing trajectory T are generated can be different. For example, the plurality of light spots SP can be distributed on opposite sides of the octagonal contour, and the processing trajectory T can rotate clockwise or counterclockwise along the octagonal contour; or, the plurality of light spots SP can be distributed on adjacent sides of the octagonal contour, and the processing trajectory T can rotate clockwise or counterclockwise along the octagonal contour. These symmetrical processing methods all contribute to improving the uniformity of the wafer's processed surface.

[0046] When the computing device determines that the crystal structure of the surface material belongs to the rhombohedral crystal system, it can decide that the specified light spot shape is multiple light spots corresponding to a triangular outline, and the specified processing trajectory is to process sequentially along this triangular outline. For example... Figure 6 As shown, the computing device can determine the crystal structure corresponding to the surface material based on the aforementioned chromaticity data. In this embodiment, the crystal lattice CL belongs to the rhombohedral crystal system (e.g., cubic crystal system / cubic packing). In this case, the computing device can generate a two-dimensional profile C with multiple closely arranged triangles. Next, as... Figure 7As shown, the computing device can determine that the specified spot shape is a plurality of light spots SP corresponding to a triangular contour, and the specified processing trajectory is a processing trajectory T sequentially performed along this triangular contour. Specifically, based on a two-dimensional contour with a lattice structure (e.g., a triangular contour), the methods for generating the plurality of light spots SP and the processing trajectory T can differ. For example, the plurality of light spots SP can be distributed on opposite sides of two adjacent triangular contours, and the processing trajectory T can rotate clockwise or counterclockwise along the two adjacent triangular contours; or, the plurality of light spots SP can be distributed on adjacent sides of a triangular contour, and the processing trajectory T can rotate clockwise or counterclockwise along the triangular contour before sequentially processing the next triangular contour. These symmetrical processing methods all contribute to improving the uniformity of the wafer's processed surface.

[0047] Based on the above embodiments, the processing methods for surface materials with other crystal structures can be deduced similarly. Specifically, in addition to hexagonal and rhombohedral crystal systems, crystal structures can also include cubic (simple cubic, face-centered cubic, body-centered cubic), and tetragonal (simple tetragonal, body-centered tetragonal), etc., which will not be elaborated here. Specifically, this invention can obtain the chromaticity data of the image of the processing area on the wafer surface in real time through a coaxially arranged optical sensing element to determine the type / crystal structure of the surface material, and accordingly determine the corresponding processing light pattern (spot shape) and processing trajectory to achieve accurate, fast, and highly uniform surface processing results. For example, for polycrystalline silicon, the crystal structure (cubic crystal system) of polycrystalline silicon can be determined based on its chromaticity data, and the corresponding processing light pattern (spot shape) and processing trajectory can be determined accordingly. It should be noted that this invention is not limited to using lasers to perform various surface treatments on wafers. For example, it can be used for wafer film removal, surface treatment of epitaxial layers formed by epitaxial growth in epitaxial fabrication processes, etc.

[0048] Through the aforementioned structure, the laser processing system and method disclosed in this case acquire an image of the current processing area on the wafer surface using an optical architecture that is at least partially coaxial or parallel to the laser beam. Based on the chromaticity data of the image, a spatial optical modulator is used to modulate the shape of a spot formed by the laser beam on the wafer surface. Furthermore, based on the chromaticity data, a scanning mirror assembly guides the laser beam's processing trajectory on the wafer surface. This allows for real-time monitoring of the surface material in different areas of the wafer surface and switching between specific spot shapes and scanning paths for continuous processing, achieving efficient removal of various surface materials from the wafer. Moreover, it can be performed without the use of traditional chemical wet etching solutions, saving water resources and avoiding environmental pollution.

Claims

1. A laser processing system for surface treatment of a wafer, comprising: a pulsed laser device for outputting a laser beam; a spatial light modulator disposed in an output path of the laser beam for generating a diffraction pattern to modulate a spot shape of the laser beam formed on a wafer surface; a scanning mirror set disposed in the output path of the laser beam for directing the spot shape of the laser beam to perform processing along a processing trajectory within a processing region of the wafer surface at a scanning angle under control; an optical sensing element for acquiring a feedback optical signal from the processing region of the wafer surface to generate an image, wherein a transmission path of the feedback optical signal is at least partially parallel or coaxial with the output path of the laser beam; and a computing device connected to the spatial light modulator, the optical sensing element and the scanning mirror set for controlling the spatial light modulator to generate the diffraction pattern and controlling the scanning mirror set to scan at the scanning angle according to chrominance data of the image.

2. The laser processing system of claim 1, wherein the computing device is configured to determine a specified spot shape according to the chrominance data, and control the spatial light modulator to generate the diffraction pattern according to the specified spot shape, the computing device is configured to determine a specified processing trajectory according to the chrominance data, and control the scanning mirror set to scan at the scanning angle according to the specified processing trajectory, wherein the specified spot shape comprises a plurality of light points corresponding to a polygonal contour, and the specified processing trajectory is to sequentially perform processing along the polygonal contour.

3. The laser processing system of claim 1, wherein the computing device is configured to determine a surface material within the processing region of the wafer surface according to the chrominance data and a pre-stored material-surface chrominance relationship, and control the spatial light modulator to generate the diffraction pattern and control the scanning mirror set to scan at the scanning angle according to a lattice structure of the surface material.

4. The laser processing system of claim 3, wherein the computing device is configured to determine a specified spot shape as a plurality of light points corresponding to an octagonal contour when judging that the lattice structure of the surface material belongs to a hexagonal system, and determine a specified processing trajectory as sequentially performing processing along the octagonal contour.

5. The laser processing system of claim 3, wherein the computing device is configured to determine a specified spot shape as a plurality of light points corresponding to a triangular contour when judging that the lattice structure of the surface material belongs to a rhombohedral system, and determine a specified processing trajectory as sequentially performing processing along the triangular contour.

6. The laser processing system of claim 3, wherein pre-stored materials in the pre-stored material-surface chrominance relationship comprise at least one of silicon dioxide, a high dielectric constant material and a low dielectric constant material, wherein the high dielectric constant material and the low dielectric constant material are compared to a dielectric constant of silicon dioxide as a reference.

7. The laser processing system of claim 6, wherein the high dielectric constant material or the low dielectric constant material comprises silicon nitride or polysilicon.

8. The laser processing system of claim 1, wherein the spatial light modulator comprises a liquid crystal display, and the operation device is configured to control the spatial light modulator to generate the diffraction pattern according to the Fourier transform result.

9. The laser processing system of claim 1, further comprising a beam splitter disposed between the wafer and the optical sensing element, and configured to direct the feedback light signal to the optical sensing element.

10. The laser processing system of claim 9, wherein the optical sensing element and the beam splitter are disposed before the scanning mirror group.

11. A laser processing method for surface treatment of a wafer by a pulsed laser device, comprising: providing a laser processing system comprising a pulsed laser device, a spatial light modulator, a scanning mirror group, an optical sensing element, and an operation device, wherein the optical sensing element is configured to obtain a feedback light signal from a processing region on a wafer surface, and a transmission path of the feedback light signal is at least partially parallel or coaxial with an output path of a laser beam; and performing, by the operation device: obtaining an image of the processing region on the wafer surface by the optical sensing element; controlling the spatial light modulator to generate a diffraction pattern according to chrominance data of the image to modulate a spot shape of the laser beam output by the pulsed laser device on the wafer surface; and controlling the scanning mirror group to direct the spot shape of the laser beam to process along a processing trajectory within the processing region on the wafer surface according to the chrominance data.

12. The laser processing method of claim 11, wherein controlling the spatial light modulator to generate the diffraction pattern according to the chrominance data of the image comprises: determining a specified spot shape according to the chrominance data, and controlling the spatial light modulator to generate the diffraction pattern according to the specified spot shape; and wherein controlling the scanning mirror group to direct the spot shape of the laser beam to process along the processing trajectory according to the chrominance data comprises: determining a specified processing path according to the chrominance data, and controlling the scanning mirror group to scan at the scanning angle according to the specified processing path, wherein the specified spot shape comprises a plurality of light points corresponding to a polygonal contour, and the specified processing trajectory is to sequentially process along the polygonal contour.

13. The laser processing method of claim 11, wherein controlling the spatial light modulator to generate the diffraction pattern according to the chrominance data, and controlling the scanning mirror group to direct the spot shape of the laser beam to process along the processing trajectory according to the chrominance data comprises: determining a surface material within the processing region on the wafer surface according to the chrominance data and a pre-stored material-surface chrominance relationship; and controlling the spatial light modulator to generate the diffraction pattern and controlling the scanning mirror group to scan at the scanning angle according to a lattice structure of the surface material.

14. The laser processing method of claim 13, wherein controlling the spatial light modulator to generate the diffraction pattern and controlling the scanning mirror group to scan at the scanning angle according to the lattice structure of the surface material comprises: ​ ​ ​ ​ ​ ​ wherein ​ ​ ​ ​ ​ When it is judged that the crystal structure of the surface material belongs to the hexagonal system, a specified spot shape is determined to be a plurality of light spots corresponding to an octagonal contour, and a specified machining track is determined to be sequentially machined along the octagonal contour.

15. The laser machining method of claim 13, wherein controlling the spatial light modulator to generate the diffraction pattern and controlling the scanning mirror set to scan at the scanning angle according to the crystal structure of the surface material comprises: When it is judged that the crystal structure of the surface material belongs to the rhombohedral system, a specified spot shape is determined to be a plurality of light spots corresponding to a triangular contour, and a specified machining track is determined to be sequentially machined along the triangular contour.

16. The laser machining method of claim 13, wherein the pre-stored material in the pre-stored material-surface colorimetric relationship comprises at least one of silicon dioxide, a high dielectric constant material, and a low dielectric constant material, wherein the high dielectric constant material and the low dielectric constant material are compared to a dielectric constant of silicon dioxide.

17. The laser machining method of claim 16, wherein the high dielectric constant material or the low dielectric constant material comprises silicon nitride or polysilicon.

18. The laser machining method of claim 11, wherein the diffraction pattern is generated according to a Fourier transform result.

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