A dual-laser-beam diamond synchronous polishing device and method

Abstract

This invention discloses a dual-laser-beam diamond synchronous polishing device and method, relating to the field of semiconductor material laser processing technology. The device includes: a laser generator for generating pulsed laser light; a homogenization and shaping unit for homogenizing and shaping the pulsed laser light to obtain a square-topped laser spot; a multi-path processing unit for dividing the homogenized and modulated pulsed laser light into two sub-pulse laser beams with different energy ratios and different incident angles on the diamond surface; and a three-dimensional motion platform for carrying the diamond and controlling the relative motion between the diamond and the two sub-pulse laser beams. The laser spots of the two sub-pulse laser beams overlap on the diamond surface along the scanning path. Based on a set scanning speed and scanning line spacing, the diamond is scanned and polished according to the scanning path. This method achieves simultaneous generation and removal of graphitization using a single-source dual-beam system, reducing the number of scans, lowering processing time, and improving processing quality.

Description

Technical Field

[0001] This invention relates to the field of laser processing technology for semiconductor materials, and in particular to a dual-laser-beam diamond synchronous polishing device and method. Background Technology

[0002] Currently, diamond polishing methods mainly include mechanical polishing, chemical mechanical polishing, plasma polishing, and laser polishing. Laser polishing, as a non-contact processing method, has become one of the mainstream technologies for precision diamond polishing due to its advantages such as high processing efficiency, no mechanical damage, strong processing flexibility, and ability to process complex curved surfaces.

[0003] Current laser polishing technologies mostly employ a single circular Gaussian pulse laser to scan and process diamond. The core principle is to use the high energy of the laser to graphitize localized areas of the diamond surface, and then polish the surface through the volatilization or peeling of the graphitized layer. However, this single circular Gaussian pulse laser polishing method has many insurmountable technical drawbacks, severely limiting further improvements in its processing efficiency and quality.

[0004] On the one hand, the energy distribution of circular Gaussian pulse lasers is uneven, with high energy density in the central region and low energy density in the edge region, resulting in uneven graphitization on the diamond surface. This leads to high surface roughness after polishing, making it difficult to achieve high-quality surface processing. On the other hand, in order to compensate for the processing defects caused by uneven energy distribution, the diamond needs to be scanned repeatedly. This not only significantly increases processing time and reduces processing efficiency, but also causes cumulative damage to the diamond surface due to multiple scans, affecting its surface integrity.

[0005] On the other hand, during single-pulse laser processing, the graphitization layer formed on the diamond surface strongly shields subsequent incident laser beams, preventing laser energy from being effectively transferred to the diamond substrate surface. This not only further reduces processing efficiency but also, due to incomplete removal of the graphitization layer, leaves residues on the diamond surface, affecting polishing quality and subsequent performance. Furthermore, existing laser polishing devices mostly employ fixed laser incident angles and single scanning path control methods, making it difficult to flexibly adjust the relative position of the laser and diamond and the scanning parameters, resulting in poor processing flexibility and limited applicability. Summary of the Invention

[0006] To address the aforementioned issues, this invention proposes a dual-laser-beam diamond synchronous polishing device and method. The device employs a homogenizing fiber to homogenize and shape the pulsed laser. A multi-processing unit divides the modulated pulsed laser into two sub-pulse laser beams with different energy ratios and incident on the diamond surface at different angles. This enables simultaneous generation and removal of graphitization using a single-source dual-beam system, reducing the number of scans, decreasing processing time, and improving processing efficiency and quality.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides a dual-laser-beam diamond synchronous polishing device, comprising:

[0009] A laser generator is used to produce pulsed laser light.

[0010] The homogenization and shaping unit is used to homogenize and shape the pulsed laser to obtain a square-topped laser spot;

[0011] The multi-processing unit is used to divide the pulsed laser modulated by the homogenization and shaping unit into two sub-pulse laser beams with different energy ratios and different incident angles on the diamond surface.

[0012] A three-dimensional motion platform is used to carry the diamond and control the relative motion between the diamond and two sub-pulse laser beams. The laser spots of the two sub-pulse laser beams on the diamond surface overlap on a preset scanning path, and the diamond is scanned and polished according to the set scanning speed and scanning line spacing.

[0013] As an alternative implementation, the homogenization and shaping unit includes a first focusing lens, a homogenizing fiber, and a second focusing lens arranged sequentially along the optical path;

[0014] The first focusing lens is used to focus and couple the pulsed laser so as to couple the pulsed laser into the homogenizing fiber;

[0015] The homogenizing fiber uses total internal reflection technology to homogenize and modulate the energy of the pulsed laser, generating a square flat-topped pulsed laser spot.

[0016] The second focusing lens is used to shape the pulsed laser emitted from the homogenizing fiber, adjust the size of the laser spot, and adjust the emission angle of the pulsed laser to be incident on the multi-processing unit.

[0017] As an alternative implementation, the polishing apparatus further includes a first sub-beam adjustment unit and a second sub-beam adjustment unit disposed between the multi-processing unit and the three-dimensional motion platform; the first sub-beam adjustment unit is used to adjust the angle of the first sub-pulse laser beam incident on the diamond surface, and the second sub-beam adjustment unit is used to adjust the angle of the second sub-pulse laser beam incident on the diamond surface.

[0018] As an alternative implementation, in the two sub-pulse laser beams, the power of the first sub-pulse laser beam is greater than that of the second sub-pulse laser beam. Along the scanning direction, the laser spot of the second sub-pulse laser beam is behind the laser spot of the first sub-pulse laser beam and coincides with the laser spot of the first sub-pulse laser beam on the scanning path.

[0019] As an alternative implementation, the angle between the first sub-pulse laser beam and the second sub-pulse laser beam is 80°.

[0020] As an alternative implementation, the angle between the irradiation direction of the first sub-pulse laser beam and the diamond surface is 10°, and the irradiation direction of the second sub-pulse laser beam is perpendicular to the diamond surface.

[0021] As an alternative implementation, a first sub-pulse laser beam is used to irradiate diamond to induce graphitization, and a second sub-pulse laser beam is used to remove the graphitization.

[0022] In a second aspect, the present invention provides a dual-laser-beam diamond synchronous polishing method, utilizing the dual-laser-beam diamond synchronous polishing apparatus of the first aspect, comprising:

[0023] The scanning speed and scanning line spacing are determined based on the required spot spacing for the arrangement of the square flat-top laser spots.

[0024] A square-topped laser spot is obtained by homogenizing and shaping the pulsed laser generated by the laser generator using a homogenizing fiber.

[0025] After homogenization and shaping, the pulsed laser is divided into a first sub-pulse laser beam and a second sub-pulse laser beam with different energy ratios and different incident angles on the diamond surface by a multi-processing unit. The power of the first sub-pulse laser beam is greater than that of the second sub-pulse laser beam. Along the scanning direction, the laser spot of the second sub-pulse laser beam is after the laser spot of the first sub-pulse laser beam and coincides with the laser spot of the first sub-pulse laser beam on the scanning path.

[0026] The relative motion between the diamond and two sub-pulse laser beams is controlled by a three-dimensional motion platform. Based on the scanning speed and the scanning line spacing, the diamond is scanned and polished along a preset scanning path.

[0027] As an alternative implementation, before homogenization and shaping using a homogenizing fiber, the pulsed laser generated by the laser generator is focused and coupled using a first focusing lens to couple the pulsed laser into the homogenizing fiber.

[0028] As an alternative implementation, after homogenizing and shaping with a homogenizing fiber, the pulsed laser emitted from the homogenizing fiber is further shaped using a second focusing lens to adjust the size of the laser spot and the emission angle so that the pulsed laser is incident on the multi-channel processing unit.

[0029] As an alternative implementation, by controlling the size of the square flat-top laser spot, the effect achieved in a single processing step is greater than or equal to the effect achieved in three Gaussian spot processing steps.

[0030] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0031] This invention proposes a dual-laser-beam diamond synchronous polishing device and method. It employs a homogenizing fiber to homogenize and shape the pulsed laser, achieving uniform scanning of the diamond by a square, flat-topped laser pulse. A three-dimensional motion platform adjusts the relative position of the diamond and the pulsed laser, controlling the diamond scanning path and scanning spacing to ensure the distance between laser spots is equal to the spot diameter. Two sub-pulse laser beams, one high-energy and one low-energy, are synchronized in time and delayed in space to generate and remove graphitization. A single scan achieves the effect of multiple scans using a traditional circular Gaussian pulsed laser, reducing the number of scans, lowering processing time, improving processing efficiency, and minimizing the shielding effect of graphitization on the laser, resulting in high-quality surface finishing.

[0032] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0034] Figure 1 This is a schematic diagram of the dual-laser-beam diamond synchronous polishing device provided in Embodiment 1 of the present invention;

[0035] Figure 2 This is a schematic diagram of the processing path for a circular Gaussian spot scanning.

[0036] Figure 3 This is a schematic diagram of the spot movement path for synchronous polishing with dual laser beams provided in Embodiment 1 of the present invention;

[0037] Figure 4 This is a schematic diagram showing the initial scanning positions of the laser spot of the high-energy (high) first sub-pulse laser beam and the low-energy (low) second sub-pulse laser beam provided in Embodiment 1 of the present invention.

[0038] Among them, 100 is the laser generator; 200 is the homogenization and shaping unit; 300 is the multi-channel processing unit; 410 is the first sub-beam adjustment unit; 420 is the second sub-beam adjustment unit; 500 is the diamond; and 600 is the three-dimensional motion platform. Detailed Implementation

[0039] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0040] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0041] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, unless the context clearly indicates otherwise, the singular form is intended to include the plural form as well. Furthermore, it should be understood that the terms “comprising” and “including”, and any variations thereof, are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or apparatus that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0042] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0043] Example 1

[0044] This embodiment provides a dual-laser-beam diamond synchronous polishing device. It uses a homogenizing fiber to homogenize and shape the pulsed laser. The modulated pulsed laser is divided into two sub-pulse laser beams with different energy ratios and different incident angles on the diamond 500 surface by a multi-processing unit 300. This enables the generation and removal of graphitization by a single source and dual beams simultaneously, reducing the number of scans, reducing processing time, and improving processing efficiency and quality.

[0045] like Figure 1 As shown, it specifically includes: a laser generator 100, a homogenization and shaping unit 200, a multi-channel processing unit 300, a first sub-beam adjustment unit 410, a second sub-beam adjustment unit 420, a diamond 500, and a three-dimensional motion platform 600.

[0046] Laser generator 100 is used to generate circular Gaussian pulse lasers.

[0047] The homogenization and shaping unit 200 is used to homogenize and shape the pulsed laser generated by the laser generator 100 to obtain a square flat-topped laser spot.

[0048] The multi-processing unit 300 is used to divide the pulsed laser modulated by the homogenization and shaping unit 200 into two sub-pulse laser beams with different energy ratios and different incident angles on the surface of the diamond 500.

[0049] The three-dimensional motion platform 600 is used to carry the diamond 500 and control the relative motion between the diamond 500 and the two sub-pulse laser beams. The laser spots of the two sub-pulse laser beams on the surface of the diamond 500 coincide on the preset scanning path, and the diamond 500 is scanned and polished according to the set scanning speed and scanning line spacing.

[0050] In this embodiment, the homogenization and shaping unit 200 includes a first focusing lens, a homogenizing fiber, and a second focusing lens arranged sequentially along the optical path;

[0051] The first focusing lens is used to focus and couple the pulsed laser to couple the pulsed laser into the homogenizing fiber, so as to optimize the transmission efficiency of the pulsed laser in the homogenizing fiber.

[0052] The homogenizing fiber uses total internal reflection technology to homogenize and modulate the energy of the incident pulsed laser, generating a square flat-topped pulsed laser spot.

[0053] The second focusing lens is used to shape the pulsed laser emitted from the homogenizing fiber, adjust the size of the laser spot, and adjust the emission angle of the pulsed laser (adjust it to a small angle) so that it can be incident on the multi-processing unit 300. By controlling the size of the laser spot, the effect achieved by a single processing is greater than or equal to the effect of three Gaussian spot processing.

[0054] As an alternative implementation, by adjusting the focal length of the second focusing lens and its distance from the homogenizing fiber, the size of the emitted light spot is adapted to the multi-processing unit 300, and the energy density of a single processing is greater than or equal to the energy density of three Gaussian light spot processing operations.

[0055] In this embodiment, the device further includes a first sub-beam adjustment unit 410 and a second sub-beam adjustment unit 420 disposed between the multi-channel processing unit 300 and the three-dimensional motion platform 600;

[0056] The first sub-beam adjustment unit 410 is used to adjust the angle of the first sub-pulse laser beam incident on the surface of the diamond 500, and the second sub-beam adjustment unit 420 is used to adjust the angle of the second sub-pulse laser beam incident on the surface of the diamond 500, thereby causing the two sub-pulse laser beams to be incident on the surface of the diamond 500 at different angles.

[0057] The first sub-pulse laser beam has a higher power than the second sub-pulse laser beam. The high-energy first sub-pulse laser beam is used to irradiate diamond 500 at a small angle, causing diamond 500 to transform into graphitization. The low-energy second sub-pulse laser beam is used to quickly remove graphitization without damaging the diamond substrate under the graphite layer.

[0058] Specifically:

[0059] The angle between the high-energy first sub-pulse laser beam and the low-energy second sub-pulse laser beam is 80°.

[0060] The high-energy first sub-pulse laser beam irradiation direction is at an angle of 10° with the diamond 500 surface, and the low-energy second sub-pulse laser beam irradiation direction is perpendicular to the diamond 500 surface.

[0061] Along the scanning direction, the laser spot of the low-energy second sub-pulse laser beam is after the laser spot of the high-energy first sub-pulse laser beam and overlaps on the scanning path, so that the generation and removal of graphitization are spatially delayed but occur simultaneously in time, achieving the effect of synchronous polishing.

[0062] Thus, high-energy lasers and low-energy lasers are respectively irradiated at small angles and perpendicularly onto the surface of diamond 500, simultaneously generating and removing graphitization, achieving high-efficiency and high-quality rapid processing.

[0063] As one alternative implementation method, the power adjustment design process for the two sub-pulse laser beams is as follows:

[0064] The core basis for power calculation is the diamond graphitization energy threshold. Graphite removal energy threshold And must meet To ensure that the low-energy laser removes only graphite without damaging the diamond substrate, the power calculation formula for the two sub-lasers is derived by combining the laser spot area and pulse parameters.

[0065] (1) The energy of a single-pulse laser is In the formula: E is the single-pulse laser energy (unit: J), P is the average laser power (unit: W), and f is the pulse repetition frequency (unit: Hz).

[0066] (2) The energy density of the laser acting on the surface of diamond 500 is: In the formula: Where is the energy density (unit: J / cm²), and S is the spot area (unit: cm²). The angle between the sub-pulse laser beam and the diamond surface (unit: °). It is used to correct the effect of the incident angle on the energy density, such as cos90°=1 for vertical incident and cos10°≈0.9848 for small incident angle.

[0067] (3) The first sub-pulse laser beam (graphitized) must meet its energy density requirements. Substituting into the single-pulse laser energy formula, the power P1 is derived as follows: ; The angle between the first sub-pulse laser beam and the diamond surface is the incident angle.

[0068] The second sub-pulse laser beam (graphite removal) must meet its energy density requirements. and Derivation of power P2: ; The angle between the second sub-pulse laser beam and the diamond surface is the incident angle.

[0069] As one possible implementation method, the design process for adjusting the incident angle is as follows:

[0070] (1) Incident angle β1 of the first sub-pulse laser beam:

[0071] To increase the effective area of ​​the pulsed laser on the diamond 500 surface and reduce the local energy density (avoiding direct damage to the diamond 500), the first sub-pulse laser beam is incident at a small angle. Simultaneously, to ensure the energy reaches the graphitization threshold, and considering the diamond surface reflectivity R (commonly R = 0.15-0.20), the optimal angle range for small-angle incident is: .

[0072] Substitute the typical parameters, =5J / cm², S=0.01cm², R=0.18, P1=250W, f=5kHz: ;Pick (Close to the optimal value) satisfies the graphitization energy requirements while avoiding spot shift caused by excessively small angles.

[0073] (2) The purpose of the second sub-pulse laser beam being incident perpendicularly is to make the laser energy act perpendicularly on the graphite layer, maximize the graphite removal efficiency, and avoid the spot shift caused by the angle deviation.

[0074] As an alternative implementation, both the first sub-beam adjustment unit 410 and the second sub-beam adjustment unit 420 include at least two mirrors (such as 45° mirrors) or prisms to correct the incident direction of the two sub-pulse laser beams.

[0075] In the aforementioned device, within the multi-processing unit 300, a polarizing beam splitter splits a pulsed laser into two sub-pulse laser beams with different polarization states. A half-wave plate controls the energy ratio of the two pulse laser beams. The polarizing beam splitter is typically formed by bonding the bottom edges of two 45° isosceles right-angle prisms together.

[0076] By irradiating the diamond 500 with a high-energy first sub-pulse laser beam at a small angle, damage to the diamond 500 substrate below graphitization is reduced. After the surface diamond is ablated and removed, the low-thickness graphite layer generated by the high-energy laser beam is removed by defocusing scanning with a low-energy second sub-pulse laser beam, thus achieving a high-quality processing effect.

[0077] The following is a basic method to achieve this goal:

[0078] First, prepare a square flat-top laser beam, which can be a high-quality beam modulated and shaped by the homogenizing and shaping unit 200; then adjust the energy ratio of the two sub-pulse laser beams split by the polarization beam splitter by a half-wave plate; and then make the high-energy first sub-pulse laser beam and the low-energy second sub-pulse laser beam incident on the surface of the diamond 500 at small angles and perpendicularly through two 45° reflectors at different spatial positions, synchronously generating and removing graphitization, improving the processing quality and reducing the processing time.

[0079] It should be noted that the above process only basically describes how to use laser beams with different energies to control the generation and removal of graphitization in sequence. The specific implementation methods and adjustment steps may vary according to actual applications and equipment. In addition, without changing the hardware equipment, this invention can meet various processing requirements, improve the processing freedom, and achieve efficient polishing of the diamond 500.

[0080] In the traditional laser polishing method, to focus a circular Gaussian spot on the surface of the diamond 500, the pulsed laser is scanned on the diamond 500 according to a preset scanning path and scanning speed, and after the scanning is completed, multiple scans are performed with different scanning speeds and scanning line spacings to finally obtain a reasonable spot overlap rate. As Figure 2 shown, the scanning path is in the shape of a "ji" character.

[0081] The dual-laser-beam diamond synchronous polishing device proposed in this embodiment scans and processes the diamond 500. As Figures 3-4 shown, the specific operation process is as follows: The laser generator 100 is used to generate pulsed laser; the homogenizing and shaping unit 200 is used to homogenize and shape the pulsed laser generated by the laser generator 100 to achieve a square flat-top spot at the focal point; the multi-channel processing unit 300 is used to divide the pulsed laser modulated by the homogenizing and shaping unit 200 into two sub-pulse laser beams with high energy and low energy. The high-energy first sub-pulse laser beam is used to irradiate the diamond 500 at a small angle to transform the diamond 500 into graphitization, and the low-energy second sub-pulse laser beam is used to quickly remove the graphitization without damaging the diamond substrate under the graphite layer; by controlling the three-dimensional motion platform 600, the two sub-pulse laser beams are scanned according to a preset scanning path, and thus scanned and processed according to the set scanning speed and scanning line spacing to achieve single-time uniform scanning and polishing.

[0082] In summary, the dual-laser-beam diamond synchronous polishing device provided in this embodiment, compared with the traditional single-beam Gaussian pulse laser scanning processing method, only requires one scan of the diamond 500, thus improving the number of scans and significantly shortening the processing time. In addition, there is no need to unload the diamond 500, improving processing stability. Moreover, by controlling the energy ratio of the two sub-pulse laser beams, different materials can be scanned and processed, greatly improving processing efficiency and solving the problems of low processing efficiency, long processing time, and poor quality in existing processes.

[0083] Example 2

[0084] Based on the above-mentioned dual-laser beam diamond synchronous polishing device, this embodiment provides a dual-laser beam diamond synchronous polishing method, including:

[0085] Based on the spot spacing required for the close arrangement of laser spots on a square flat-topped surface, the spot spacing can be designed as the spot diameter to determine the laser scanning speed and scanning line spacing required when setting parameters for the three-dimensional motion platform 600.

[0086] A first focusing lens is used to focus and couple the pulsed laser generated by the laser generator 100 into the homogenizing fiber, so as to optimize the transmission efficiency of the pulsed laser in the homogenizing fiber.

[0087] A square-topped laser spot is obtained by homogenizing and shaping the focused pulsed laser using a homogenizing fiber.

[0088] A second focusing lens is used to shape the pulsed laser emitted from the homogenizing fiber, adjusting the size of the laser spot and the emission angle so that the pulsed laser is incident into the multi-channel processing unit 300 in the form of small-angle light.

[0089] The modulated pulsed laser is split into two sub-pulse laser beams with different energy ratios and different incident angles on the surface of the diamond 500 by the multi-processing unit 300. Along the scanning direction, the laser spot of the low-energy second sub-pulse laser beam is after the laser spot of the high-energy first sub-pulse laser beam and they overlap on the scanning path, so that the generation and removal of graphitization are delayed in space and occur simultaneously in time, achieving the effect of synchronous polishing.

[0090] The diamond 500 is controlled by a three-dimensional motion platform 600 to move relative to two sub-pulse laser beams. Based on the scanning speed and the scanning line spacing, the diamond 500 is scanned and polished along a preset scanning path.

[0091] In this embodiment, the homogenizing fiber uses total internal reflection technology to homogenize and modulate the energy of the incident light to generate a square flat-top pulsed laser. At the same time, by controlling the size of the square flat-top laser spot, the effect achieved by a single processing is greater than or equal to the effect achieved by three Gaussian spot processing.

[0092] The multi-processing unit splits the laser beam into two sub-pulse laser beams, and the energy ratio between the two sub-pulse laser beams is adjusted by a half-wave plate. This allows the high-energy first sub-pulse laser beam and the low-energy second sub-pulse laser beam to irradiate the diamond 500 surface at a small angle and perpendicularly, respectively, to simultaneously generate and remove graphitization, thus achieving high-efficiency and high-quality rapid processing.

[0093] The angle between the two sub-pulse laser beams is 80°, the angle between the direction of the high-energy first sub-pulse laser beam and the surface of the diamond 500 is 10°, and the direction of the low-energy second sub-pulse laser beam is perpendicular to the surface of the diamond 500.

[0094] Compared to existing technologies, this embodiment achieves synchronous processing of high-energy square flat-top laser beams and low-energy square flat-top laser beams through homogenization processing by homogenization and shaping unit 200 and beam splitting by multi-path processing unit 300. Furthermore, the relative position of diamond 500 and pulsed laser is adjusted by three-dimensional motion platform 600, thereby controlling the scanning path and scanning interval of diamond 500. The effect of multiple scans by traditional circular Gaussian pulsed laser can be achieved in a single scan, reducing processing time, improving processing efficiency, reducing damage to the diamond substrate, and improving processing quality.

[0095] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A dual-laser-beam diamond synchronous polishing device, characterized in that, include: A laser generator is used to produce pulsed laser light. The homogenization and shaping unit is used to homogenize and shape the pulsed laser to obtain a square-topped laser spot; The multi-processing unit is used to divide the pulsed laser modulated by the homogenization and shaping unit into two sub-pulse laser beams with different energy ratios and different incident angles on the diamond surface. A three-dimensional motion platform is used to carry the diamond and control the relative motion between the diamond and two sub-pulse laser beams. The laser spots of the two sub-pulse laser beams on the diamond surface overlap on a preset scanning path, and the diamond is scanned and polished according to the set scanning speed and scanning line spacing. In the two sub-pulse laser beams, the power of the first sub-pulse laser beam is greater than that of the second sub-pulse laser beam. Along the scanning direction, the laser spot of the second sub-pulse laser beam is after the laser spot of the first sub-pulse laser beam and coincides with the laser spot of the first sub-pulse laser beam on the scanning path. The angle between the irradiation direction of the first sub-pulse laser beam and the diamond surface is 10°, and the irradiation direction of the second sub-pulse laser beam is perpendicular to the diamond surface. The first sub-pulse laser beam is used to irradiate the diamond to induce graphitization, and the second sub-pulse laser beam is used to remove the graphitization.

2. The dual-laser-beam diamond synchronous polishing device as described in claim 1, characterized in that, The homogenization and shaping unit includes a first focusing lens, a homogenizing fiber, and a second focusing lens arranged sequentially along the optical path. The first focusing lens is used to focus and couple the pulsed laser so as to couple the pulsed laser into the homogenizing fiber; The homogenizing fiber uses total internal reflection technology to homogenize and modulate the energy of the pulsed laser, generating a square flat-topped pulsed laser spot. The second focusing lens is used to shape the pulsed laser emitted from the homogenizing fiber, adjust the size of the laser spot, and adjust the emission angle of the pulsed laser to be incident on the multi-processing unit.

3. The dual-laser-beam diamond synchronous polishing device as described in claim 1, characterized in that, The polishing apparatus also includes a first sub-beam adjustment unit and a second sub-beam adjustment unit located between the multi-processing unit and the three-dimensional motion platform; the first sub-beam adjustment unit is used to adjust the angle of the first sub-pulse laser beam incident on the diamond surface, and the second sub-beam adjustment unit is used to adjust the angle of the second sub-pulse laser beam incident on the diamond surface.

4. The dual-laser-beam diamond synchronous polishing device as described in claim 1, characterized in that, The angle between the first sub-pulse laser beam and the second sub-pulse laser beam is 80°.

5. A method for simultaneous polishing of diamond using dual laser beams, characterized in that, The dual-laser-beam diamond synchronous polishing apparatus according to any one of claims 1-4 comprises: The scanning speed and scanning line spacing are determined based on the required spot spacing for the arrangement of the square flat-top laser spots. A square-topped laser spot is obtained by homogenizing and shaping the pulsed laser generated by the laser generator using a homogenizing fiber. After homogenization and shaping, the pulsed laser is divided into a first sub-pulse laser beam and a second sub-pulse laser beam with different energy ratios and different incident angles on the diamond surface by a multi-processing unit. The power of the first sub-pulse laser beam is greater than that of the second sub-pulse laser beam. Along the scanning direction, the laser spot of the second sub-pulse laser beam is after the laser spot of the first sub-pulse laser beam and coincides with the laser spot of the first sub-pulse laser beam on the scanning path. The relative motion between the diamond and two sub-pulse laser beams is controlled by a three-dimensional motion platform. Based on the scanning speed and the scanning line spacing, the diamond is scanned and polished along a preset scanning path.

6. The method for simultaneous polishing of diamond using dual laser beams as described in claim 5, characterized in that, Before homogenization and shaping using homogenizing fiber, the process also includes using a first focusing lens to focus and couple the pulsed laser generated by the laser generator into the homogenizing fiber. After homogenization and shaping using homogenizing fiber, the process also includes using a second focusing lens to shape the pulsed laser emitted from the homogenizing fiber, adjusting the size of the laser spot and the emission angle so that the pulsed laser is incident on the multi-channel processing unit.

7. The method for simultaneous polishing of diamond using dual laser beams as described in claim 6, characterized in that, By controlling the size of the square flat-top laser spot, the effect achieved in a single processing step can be greater than or equal to the effect achieved in three Gaussian spot processing steps.

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