Silicon carbide wafer laser synergetic colloidal medium assisted fine grinding method

Abstract

The invention discloses a silicon carbide wafer laser and colloid medium assisted micro-grinding method, which belongs to the field of precision machining, and specifically comprises two procedures of sandwich structure colloid spraying and laser assisted micro-grinding. The step of spraying the colloid with the sandwich structure comprises two steps of determining a processing path and periodically spraying, and spraying the colloid with the periodic sandwich structure formed by sequentially stacking a strong oxidant layer and a nano abrasive material layer on a fine grinding feed path; the laser-assisted micro-grinding is divided into four steps of laser process parameter setting, grinding process parameter setting, laser induction and micro-grinding processing, the laser-assisted micro-grinding is carried out along a covering route of the sandwich structure colloid, firstly, a strong oxidant layer in the laser-induced colloid and a silicon carbide wafer are subjected to chemical modification to be softened, and then the laser-assisted micro-grinding is carried out along the covering route of the sandwich structure colloid. And then the nanometer abrasive material layer is driven through fine grinding to remove the to-be-machined material, the quality defects such as microcracks and burrs are reduced, and therefore the high-quality, high-efficiency and low-damage precision machining effect is achieved.

Description

Technical Field

[0001] This invention belongs to the field of precision machining technology for hard and brittle materials, specifically relating to a laser-assisted colloidal medium-assisted micro-grinding method for silicon carbide wafers. Background Technology

[0002] Precision machining technology has become an indispensable key technology in modern manufacturing, especially in the processing of hard and brittle materials, where its application value is prominent. This technology enables the manufacture of high-precision optical components, semiconductor chips, ceramic parts, and other core products, all of which play crucial roles in their respective fields. However, due to their high hardness and brittleness, it is difficult to ensure processing quality for hard and brittle materials such as silicon carbide. Currently, laser-assisted micro-grinding technology has been widely adopted in the processing of hard and brittle materials. However, laser processing of silicon carbide not only generates microscopic defects such as microcracks and localized melting, but also faces technical bottlenecks such as the difficulty in controlling process parameters. Furthermore, the grinding fluid used in this process contains certain toxic components, posing potential hazards to the health of operators and the environment. In summary, existing laser-assisted micro-grinding processes have certain technical shortcomings in the processing of silicon carbide.

[0003] To address the aforementioned technical challenges, it is necessary to design a laser-assisted colloidal medium-assisted micro-grinding method for silicon carbide wafers. This sandwich-structured colloid can replace grinding fluid sprayed onto the surface of silicon carbide wafers. On the one hand, it softens the material, facilitating laser-assisted micro-grinding; on the other hand, this sandwich-structured colloid is less toxic than traditional grinding fluids, possessing significant environmental advantages and positive implications for environmental protection.

[0004] Domestic scholars have proposed a variety of ultra-precision composite grinding methods.

[0005] Chinese invention patent CN114406375A discloses an electrochemical discharge-energized micro-grinding method for silicon-based material micro-parts. This method employs electrochemical discharge technology, using a micro-grinding tool to electrochemically energize the workpiece's surface area within the discharge region, transforming it into a modified layer with significantly reduced mechanical properties. Finally, the micro-grinding tool rapidly and efficiently removes this modified layer, achieving high precision, high efficiency, and low damage. However, the high temperatures generated by the electrochemical discharge energization in this invention can easily lead to micro-grinding tool breakage during prolonged operation, resulting in losses. In contrast, this invention uses a strong oxidizing agent colloid to directly oxidize the workpiece, eliminating the need for micro-grinding tool energization. Laser-assisted grinding further enhances the physical and chemical coupling, reducing damage to the diamond micro-abrasive grains and avoiding the risk of damage or even breakage of the diamond micro-grinding tool. This extends the lifespan of the micro-grinding tool while improving grinding efficiency and reducing negative effects such as micro-cracks, edge chipping, and surface roughness.

[0006] Chinese invention patent CN108098460A discloses a chemically modified liquid and a chemical mechanical micro-grinding method. This method uses a modified liquid that can chemically react with silicon-based materials such as silicon, silicon carbide, and quartz glass under grinding heat and mechanical stress to generate a silicate layer modifier, reducing the surface hardness of the material. By synergistically combining force, heat, and chemical energy, the mechanical action during material removal is weakened, thereby reducing damage such as micro-chipping, micro-pitting, and micro-cracks on edges and the processed surface during the micro-grinding of hard and brittle silicon-based materials. However, the chemically modified liquid in this invention chemically modifies non-processed areas, altering the original physicochemical properties of the substrate. In contrast, the sandwich-structured colloid used in this invention is sprayed onto the workpiece surface along the path traversed by the micro-grinding tool through a pre-defined path coating, thus chemically modifying only the areas to be processed, avoiding damage to non-processed areas. Furthermore, due to the solidification stability of the colloid, the sprayed chemically modified liquid will not deviate due to factors such as grinding platform vibration, thus better ensuring the stability of the modified area.

[0007] Chinese invention patent CN110842761A discloses a photocatalytic high-energy field-assisted chemical-mechanical composite micro-grinding method. This method involves supplying an alkaline chemical modification liquid to the surface of a silicon-based material part. First, an ultraviolet laser scans along a preset path, where the material in the scanned area is photocatalytically modified into an oxide layer. Then, an infrared laser scans along the same path again, and under the assistance of a high-energy field, the oxide layer undergoes further chemical modification into a silicate layer. This ultraviolet-infrared-chemical-mechanical composite micro-grinding process is repeated until the required dimensional dimensions are achieved. While this invention enhances the efficiency of the chemical modification liquid, the step-by-step composite micro-grinding process chain is complex and cumbersome. In contrast, this invention only requires one laser treatment of the workpiece surface area. By using a sandwich-structured colloid to soften the surface before laser-assisted grinding, the grinding time is reduced, thus improving grinding efficiency. Summary of the Invention

[0008] The purpose of this invention is to address the shortcomings of laser-assisted grinding technology and chemically modified workpiece methods by providing a laser-assisted colloidal medium-assisted micro-grinding method for silicon carbide wafers. This method aims to solve quality problems such as microcracks and burrs that occur when laser-processing hard and brittle materials like silicon carbide, especially the problem of unnecessary damage to non-machined surfaces, thereby achieving low-defect, high-efficiency, and high-quality laser-assisted micro-grinding.

[0009] The above-mentioned technical objective of the present invention is achieved through the following technical solution: a method for laser-assisted colloidal medium-assisted micro-grinding of silicon carbide wafers, characterized in that it includes two processes: sandwich structure colloidal spraying and laser-assisted micro-grinding.

[0010] S1 Sandwich Structure Colloidal Spraying: A six-axis spraying robot with a dual-nozzle mechanism is used to sequentially spray a periodic sandwich structure colloidal coating consisting of a strong oxidant layer and a nano-abrasive layer onto the surface of a silicon carbide wafer using micron-level colloidal spraying technology. The strong oxidant layer can chemically modify and soften the silicon carbide surface, while the nano-abrasive layer plays a role in the precise removal of materials during the micro-grinding process.

[0011] S2 Laser-Assisted Micro Grinding: A laser-assisted micro grinding platform based on a nanosecond fiber laser is built. The processing is carried out according to the sandwich structure colloid spraying path on the surface of silicon carbide wafers. In this process, the strong oxidant layer in the sandwich structure colloid is chemically modified and softened by the laser, and then the nano abrasive layer is driven by micro grinding to remove the material to be processed.

[0012] Specifically, the S1 sandwich structure colloid spraying process includes the following steps:

[0013] S101 determines the processing path: localized spraying is performed based on the infeed path of laser-assisted micro-grinding;

[0014] S102 Periodic Spraying: Employs microfluidic colloid jetting technology, equipped with a six-axis spraying robot and a dual-nozzle actuator. One nozzle is used to spray a strong oxidizing agent colloid, while the other is used to spray a nanoparticle colloid. By controlling the spraying path and timing of the dual nozzles, a periodic sandwich-structured colloid is constructed in the micro-grinding area, with 3 to 6 layers and a single layer thickness of 5 to 10 μm.

[0015] Specifically, the S2 laser-assisted micro-grinding process includes the following steps:

[0016] S201 laser process parameter settings: Using the laser defocusing processing method, the laser power is set to 2-6W, the pulse width to 10-50ps, the scanning rate to 50-100mm / s, and the defocusing amount to 1-5mm;

[0017] S202 grinding process parameter settings: Set the distance between the micro-grinding tool and the laser beam to 5-10mm, the grinding depth to 20-200μm, the feed rate to 0.01-0.1mm / s, and the rotation speed to 1000-12000rpm;

[0018] S203 laser induction: Laser defocusing is induced based on the colloidal spraying path on the surface of silicon carbide wafers, and a softening layer is formed by photothermal / photochemical coupling between a strong oxidant layer and the material to be processed.

[0019] S204 micro-grinding: Micro-grinding is performed by following the laser-induced modification zone with diamond micro-grinding tools, which drives the dispersed free abrasive in the nano-abrasive layer to remove silicon carbide wafers with high precision.

[0020] Specifically, the sandwich-structured colloid is composed of a strong oxidizing agent layer and a nano-abrasive layer stacked sequentially. The strong oxidizing agent layer is formed by mixing a 0.01–0.1 mol / L strong oxidizing solution with a 10–15 wt% gelatin solution in a 1:2 ratio, with an acidic solvent added to control the pH value within the range of 4–5. The nano-abrasive layer is prepared by dispersing nano-sized abrasive particles with a particle size of 20–100 nm in a 10–15 wt% gelatin solution, followed by ultrasonic dispersion to form a uniform and stable nano-abrasive system.

[0021] Specifically, the method for laser-assisted colloidal medium-assisted micro-grinding of silicon carbide wafers is characterized in that the micron-level liquid jetting technology in the S1 sandwich structure colloidal spraying is based on a microfluidic system with an accuracy of ±0.5 to 2 μm, which uniformly sprays the colloidal material onto the workpiece to be processed area, with a colloidal flow rate of 5 to 100 μm / s and a nozzle moving speed of 0.1 to 0.5 mm / s.

[0022] Specifically, the silicon carbide wafers include, but are not limited to, N-type doped and P-type doped silicon carbide, and also cover other silicon carbide materials with similar processing characteristics.

[0023] Specifically, the micro-grinding tool in the S204 micro-grinding process refers to one or more of the following: diamond grain size of 3-10 μm and grinding head shape of sphere, cylinder and cone.

[0024] Specifically, the nanoscale abrasive refers to one or more of the following: conventional abrasives such as chromium oxide and cerium oxide, superhard abrasives such as cubic boron nitride and diamond, and soft abrasives such as iron oxide.

[0025] Specifically, the strong oxidizing solution refers to one or more of permanganate, dichromate, halogen and their oxyacid salts.

[0026] Compared with existing technologies, the above-mentioned laser-assisted colloidal medium-assisted micro-grinding method for silicon carbide wafers has the following advantages.

[0027] ① Laser-chemical-mechanical multi-energy field coupling processing. Laser preheating enhances the oxidizing power of strong oxidants, softening the material. Nano-abrasives simultaneously form a lubricating film to polish the workpiece, avoiding micro-cracks and thermal damage problems caused by laser-assisted micro-grinding, achieving a low-damage processing effect.

[0028] ② Localized chemical modification using sandwich-structured colloids. Microfluidic spraying technology is employed to spray sequentially stacked, periodically layered sandwich-structured colloids along the processing path. The colloid's curing characteristics ensure that modification only affects the target path, preventing degradation of the substrate material's properties due to modification of non-target areas. Strong oxidants and nano-abrasives are alternately arranged to increase the interaction area, achieving a synergistic effect of "laser-induced chemical modification followed by nano-abrasive-assisted polishing," significantly improving modification efficiency.

[0029] ③ An environmentally friendly colloid replaces traditional grinding fluid. The colloid uses gelatin as a carrier and combines a strong oxidizing solution with nano-abrasives, completely replacing toxic grinding fluids. In addition, the nano-abrasives are uniformly dispersed in the colloid system, making them less likely to remain on the workpiece surface after processing, thus reducing subsequent cleaning processes. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the colloidal spraying-laser-induced assisted micro-grinding processing platform in this invention;

[0031] Figure 2 This is a schematic diagram of laser-modified colloidal-assisted micro-grinding of silicon carbide wafers in this invention;

[0032] Figure 3 This is a flowchart of the laser-modified colloidal-assisted micro-grinding process for silicon carbide wafers in this invention;

[0033] Figure 4 This is a schematic diagram illustrating the principle of laser-modified colloidal-assisted micro-grinding of silicon carbide wafers in this invention.

[0034] Figure 5 This is a comparison of the surface morphology of silicon carbide wafers processed by pure micro-grinding and laser-modified colloidal-assisted micro-grinding in this invention. Detailed Implementation

[0035] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0036] To address the problems of microcracks and melting defects on the machined surface and unnecessary damage on the non-machined surface that easily occur when laser-assisted grinding of hard and brittle materials such as silicon carbide, this invention provides a laser-assisted colloidal medium-assisted micro-grinding method for silicon carbide wafers, achieving high-quality, high-efficiency, and low-defect localized chemical modification of laser-assisted micro-grinding.

[0037] The laser-assisted colloidal medium-assisted micro-grinding method for silicon carbide wafers, wherein the colloidal spraying-laser-induced assisted micro-grinding processing platform is as follows: Figure 1 As shown, Figure 2 , 3 As shown, the feature is that it includes two processes: sandwich structure colloid spraying and laser-assisted micro-grinding.

[0038] S1 Sandwich Structure Colloidal Spraying: A six-axis spraying robot with a dual-nozzle mechanism is used to sequentially spray a periodic sandwich structure colloidal coating consisting of a strong oxidant layer and a nano-abrasive layer onto the surface of a silicon carbide wafer using micron-level colloidal spraying technology. The strong oxidant layer can chemically modify and soften the silicon carbide surface, while the nano-abrasive layer plays a role in the precise removal of materials during the micro-grinding process.

[0039] S2 Laser-Assisted Micro Grinding: A laser-assisted micro grinding platform based on a nanosecond fiber laser is built. The processing is carried out according to the sandwich structure colloid spraying path on the surface of silicon carbide wafers. In this process, the strong oxidant layer in the sandwich structure colloid is chemically modified and softened by the laser, and then the nano abrasive layer is driven by micro grinding to remove the material to be processed.

[0040] Furthermore, the S1 sandwich structure colloid spraying process includes the following steps:

[0041] S101 determines the processing path: localized spraying is performed based on the infeed path of laser-assisted micro-grinding;

[0042] S102 Periodic Spraying: Employs microfluidic colloid jetting technology, equipped with a six-axis spraying robot and a dual-nozzle actuator. One nozzle is used to spray a strong oxidizing agent colloid, while the other is used to spray a nanoparticle colloid. By controlling the spraying path and timing of the dual nozzles, a periodic sandwich-structured colloid is constructed in the micro-grinding area, with 3 to 6 layers and a single layer thickness of 5 to 10 μm.

[0043] Furthermore, the S2 laser-assisted micro-grinding process includes the following steps:

[0044] S201 laser process parameter settings: Using the laser defocusing processing method, the laser power is set to 2-6W, the pulse width to 10-50ps, the scanning rate to 50-100mm / s, and the defocusing amount to 1-5mm;

[0045] S202 grinding process parameter settings: Set the distance between the micro-grinding tool and the laser beam to 5-10mm, the grinding depth to 20-200μm, the feed rate to 0.01-0.1mm / s, and the rotation speed to 1000-12000rpm;

[0046] S203 laser induction: Laser defocusing is induced based on the colloidal spraying path on the surface of silicon carbide wafers, and a softening layer is formed by photothermal / photochemical coupling between a strong oxidant layer and the material to be processed.

[0047] S204 micro-grinding: Micro-grinding is performed by following the laser-induced modification zone with diamond micro-grinding tools, which drives the dispersed free abrasive in the nano-abrasive layer to remove silicon carbide wafers with high precision.

[0048] Furthermore, the sandwich-structured colloid is composed of a strong oxidizing agent layer and a nano-abrasive layer stacked sequentially. The strong oxidizing agent layer is formed by mixing a 0.01–0.1 mol / L strong oxidizing solution with a 10–15 wt% gelatin solution in a 1:2 ratio, and an acidic solvent is added to control the pH value to the range of 4–5. The nano-abrasive layer is prepared by dispersing nano-sized abrasive particles with a particle size of 20–100 nm in a 10–15 wt% gelatin solution, and then ultrasonically dispersing the particles to form a uniform and stable nano-abrasive system.

[0049] Furthermore, the method for laser-assisted colloidal medium-assisted micro-grinding of silicon carbide wafers is characterized in that the micron-level liquid jetting technology in the S1 sandwich structure colloidal spraying is based on a microfluidic system with an accuracy of ±0.5 to 2 μm, which uniformly sprays the colloidal material onto the workpiece to be processed area, with a colloidal flow rate of 5 to 100 μm / s and a nozzle moving speed of 0.1 to 0.5 mm / s.

[0050] Furthermore, the silicon carbide wafers specifically include, but are not limited to, N-type doped and P-type doped silicon carbide, and also cover other silicon carbide materials with similar processing characteristics.

[0051] Furthermore, the micro-grinding tool in the S204 micro-grinding process refers to a diamond particle size of 3-10 μm and a grinding head that is spherical, cylindrical, or conical.

[0052] Furthermore, the nanoscale abrasive refers to one or more of the following: conventional abrasives such as chromium oxide and cerium oxide; superhard abrasives such as cubic boron nitride and diamond; and soft abrasives such as iron oxide.

[0053] Furthermore, the strong oxidizing solution refers to one or more of permanganate, dichromate, halogen, and their oxyacid salts.

[0054] like Figure 4As shown, the working principle of this invention is as follows: Using microfluidic system-based micron-level liquid jetting technology, a sandwich-structured colloid is sprayed onto the micro-grinding toolpath through coordinated control of dual nozzles. This colloid structure consists of a strong oxidant layer and a nano-abrasive layer stacked sequentially, forming a multi-layered composite periodic structure. The top layer of the colloid is a strong oxidant layer, the second layer below it is a nano-abrasive layer, and so on, forming six sandwich-structured colloid layers. The sandwich structure enhances the overall effectiveness of the chemically modified liquid by embedding nano-abrasives, building upon the original strong oxidant oxidation modification. This adds lubrication and polishing functions to the nano-abrasive micro-grinding process, strengthens the synergistic effect of the strong oxidant and nano-abrasives, enhances the alternating interlayer interface effect and mass transfer efficiency, improves chemical modification efficiency, and reduces damage to non-machined surfaces. Laser-induced modification of the colloidal system involves a strong oxidant layer that activates Si-C bonds on the silicon carbide wafer surface via protons, oxidizing Si to SiO2. The resulting nanoscale amorphous SiO2 layer forms a weakly bonded interface due to hydroxylation, reducing surface hardness and inducing lattice relaxation, thus softening the surface. Simultaneously, the laser-induced thermal effect disperses the nano-abrasive particles, causing strong mechanical friction against the silicon carbide surface, which facilitates subsequent micro-grinding. Furthermore, the nano-abrasive particles can adsorb a large amount of surface contaminants, providing a certain degree of cleaning. During the micro-grinding stage, polycrystalline diamond micro-abrasives are processed along the colloidal coverage path. Under the laser-induced colloidal modification pretreatment, the material removal mechanism during abrasive cutting is optimized, the abrasive cutting load is significantly reduced, the risk of micro-abrasive damage is lowered, grinding efficiency is effectively improved, and service life is extended. At the same time, grinding efficiency is greatly enhanced, further improving surface quality. Figure 5 As shown, compared with the surface morphology processed by pure grinding, the silicon carbide wafer after laser-modified colloidal assisted micro-grinding has a smaller roughness, better surface flatness, and less edge damage.

[0055] The above embodiments should be understood as being used only to illustrate the present invention more clearly, and not to limit the scope of the present invention. After reading this invention, any modifications of the present invention by those skilled in the art in various equivalent forms fall within the scope defined by the appended claims.

Claims

1. A method for laser-assisted colloidal medium-assisted micro-grinding of silicon carbide wafers, characterized in that, It includes two processes: sandwich structure colloid spraying and laser-assisted micro-grinding; S1 Sandwich Structure Colloidal Spraying: A six-axis spraying robot with a dual-nozzle mechanism is used to sequentially spray a periodic sandwich structure colloidal coating consisting of a strong oxidant layer and a nano-abrasive layer onto the surface of a silicon carbide wafer using micron-level colloidal spraying technology. The strong oxidant layer can chemically modify and soften the silicon carbide surface, while the nano-abrasive layer plays a role in the precise removal of materials during the micro-grinding process. S2 Laser-Assisted Micro Grinding: Based on a nanosecond fiber laser-assisted micro grinding platform, it processes silicon carbide wafers by following the sandwich structure colloid spraying path. The laser induces the strong oxidant layer in the sandwich structure colloid to chemically modify and soften the silicon carbide wafer. Then, the nano-abrasive layer is driven by micro grinding to remove the material to be processed.

2. The method for laser-assisted colloidal medium-assisted micro-grinding of silicon carbide wafers according to claim 1, characterized in that, The S1 sandwich structure colloid spraying process includes the following steps: S101 determines the processing path: localized spraying is performed based on the infeed path of laser-assisted micro-grinding; S102 Periodic Spraying: Employs microfluidic colloid jetting technology, equipped with a six-axis spraying robot and a dual-nozzle actuator; one nozzle is used to spray strong oxidant colloid, and the other nozzle is used to spray nanoparticle colloid. By controlling the spraying path and timing of the dual nozzles, a periodic sandwich structure colloid is constructed in the micro-grinding area, with 3 to 6 layers and a single layer thickness of 5 to 10 μm.

3. The method for laser-assisted colloidal medium-assisted micro-grinding of silicon carbide wafers according to claim 1, characterized in that, The S2 laser-assisted micro-grinding process includes the following steps: S201 laser process parameter settings: Using the laser defocusing processing method, the laser power is set to 2-6W, the pulse width to 10-50ps, the scanning rate to 50-100mm / s, and the defocusing amount to 1-5mm; S202 grinding process parameter settings: Set the distance between the micro-grinding tool and the laser beam to 5-10mm, the grinding depth to 20-200μm, the feed rate to 0.01-0.1mm / s, and the rotation speed to 1000-12000rpm; S203 laser induction: Laser defocusing is induced based on the colloidal spraying path on the surface of silicon carbide wafers, and a softening layer is formed by photothermal / photochemical coupling between a strong oxidant layer and the material to be processed. S204 micro-grinding: Micro-grinding is performed by following the laser-induced modification zone with diamond micro-grinding tools, which drives the dispersed free abrasive in the nano-abrasive layer to remove silicon carbide wafers with high precision.

4. The method for laser-assisted colloidal medium-assisted micro-grinding of silicon carbide wafers according to claim 1, characterized in that, The sandwich-structured colloid is composed of a strong oxidant layer and a nano-abrasive layer stacked sequentially. The strong oxidant layer is formed by mixing a strong oxidizing solution of 0.01–0.1 mol / L with a gelatin solution of 10–15 wt% in a 1:2 ratio, and an acidic solvent is added to control the pH value within the range of 4–5. The nano-abrasive layer is prepared by dispersing nano-sized abrasive particles with a particle size of 20–100 nm in a gelatin solution of 10–15 wt%, and then ultrasonically dispersing them to form a uniform and stable nano-abrasive system.

5. The method for laser-assisted colloidal medium-assisted micro-grinding of silicon carbide wafers according to claim 1, characterized in that, The micron-level liquid jetting technology in the S1 sandwich structure colloid spraying is based on a microfluidic system with an accuracy of ±0.5 to 2 μm, which uniformly sprays the colloid onto the workpiece to be processed area. The colloid flow rate is 5 to 100 μm / s, and the nozzle moving speed is 0.1 to 0.5 mm / s.

6. The method for laser-assisted colloidal medium-assisted micro-grinding of silicon carbide wafers according to claim 1, characterized in that, The silicon carbide wafers specifically include, but are not limited to, N-type doped and P-type doped silicon carbide, and also cover other silicon carbide-based wafers with similar processing characteristics.

7. The method for laser-assisted colloidal medium-assisted micro-grinding of silicon carbide wafers according to claim 3, characterized in that, The micro-grinding tool used in S204 micro-grinding refers to a diamond particle size of 3-10μm and a grinding head that is spherical, cylindrical, or conical.

8. The method for laser-assisted colloidal medium-assisted micro-grinding of silicon carbide wafers according to claim 4, characterized in that, The nanoscale abrasive refers to one or more of the following: conventional abrasives such as chromium oxide and cerium oxide; superhard abrasives such as cubic boron nitride and diamond; and soft abrasives such as iron oxide.

9. The method for laser-assisted colloidal medium-assisted micro-grinding of silicon carbide wafers according to claim 4, characterized in that, The strong oxidizing solution refers to one or more of permanganate, dichromate, halogen and their oxyacid salts.

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