Manufacturing method of diamond wire saw for cutting silicon carbide single crystal substrates

Abstract

This invention provides a method for manufacturing a diamond wire saw for cutting silicon carbide single-crystal substrates. First, impurities are removed from the diamond micro-powder abrasive. During the abrasive application process, the abrasive density *a* on the steel wire is monitored in real-time via images and videos, and the feeding rate of the diamond micro-powder abrasive in the feeding container is controlled accordingly, achieving a first-step closed-loop control. In the subsequent nickel plating thickening process, the concentricity of the thickened layer on the steel wire and the continuous stability of its thickness are controlled. Before winding, the wire saw diameter *d* is measured using a laser method. Based on the mapping relationship between the wire diameter *d*, abrasive density *a*, and plating thickness *c*, a second closed-loop control is implemented for the entire wire saw production process. The two closed-loop controls operate nested together, ensuring precise control throughout the entire process. The diamond wire saw obtained by this method exhibits high continuous stability in various performance indicators, ensuring good process stability during the cutting of single-crystal silicon carbide substrates, thereby reducing cutting risks.

Description

Technical Field

[0001] This invention belongs to the technical field of diamond tools, specifically a method for manufacturing a diamond wire saw for cutting silicon carbide single crystal substrates. Background Technology

[0002] Diamond wire saws are widely used as cutting tools, especially in the semiconductor field, where they are used to cut silicon ingots into silicon wafers. With the emergence of silicon carbide as a novel semiconductor material in recent years, it exhibits higher thermal stability, higher breakdown field strength, wider bandgap, and stronger radiation resistance compared to traditional silicon semiconductors. Therefore, silicon carbide semiconductors offer greater advantages over traditional silicon semiconductors in applications requiring high temperature, high pressure, high power, high frequency, and radiation resistance. Since silicon carbide is a superhard material, second only to diamond in hardness, the requirements for diamond wire saws in cutting silicon carbide ingots into wafers differ significantly from those faced by traditional silicon wafer wire saws. Due to its higher hardness, the cutting ability and stability of the wire saw must be higher to avoid problems caused by unstable diamond micron abrasive density, uneven density distribution, and unstable wire diameter, including unstable cutting force, uneven wafer thickness, wire marks, and bending due to uneven wear of the wire saw, all of which affect the cutting quality and efficiency of silicon carbide single crystal substrates. Summary of the Invention

[0003] To address the aforementioned problems, this invention proposes a method for manufacturing a diamond wire saw for cutting silicon carbide single-crystal substrates.

[0004] The technical solution of this invention is: a method for manufacturing a diamond wire saw for cutting silicon carbide single crystal substrates, characterized by comprising the following steps:

[0005] Material selection stage

[0006] (1) Diamond material selection: Select diamond raw materials with Ti not less than 70 and TTi not less than 65, crush the diamond into micro abrasive powder, shape and acid wash, and classify the diamond micro abrasive powder by overflow method. The relevant index requirements after classification are as follows, including volume distribution span < 0.68, crystal form: average roundness > 0.9, ash content < 0.05%;

[0007] (2) Pretreatment of diamond micro powder abrasive: The diamond micro powder abrasive is placed in a high vacuum of 1.0×10⁻⁶. -3 -1.0×10 -5Vacuum treatment at 300-500℃ for 6-12 hours in a vacuum furnace of PA; then, the diamond micro powder abrasive is plated with nickel alloy metal, including electroless nickel plating and electroplating. The total nickel plating thickness of the outer layer of the diamond micro powder abrasive is between 0.8-1.5μm, and the mass ratio of electroless nickel plating to electroplating nickel is controlled between 1.2 / 1 and 1.5 / 1. The surface of the diamond micro powder abrasive is completely covered without any missing plating, the coating is dense and without nodules, and the micro powder abrasive particles do not stick together.

[0008] (3) Selection of steel wire: High carbon steel wire is selected, with a total diameter deviation of ±0.5μm, wire ellipticity ≤0.5μm, breaking force deviation ≤1N, coil diameter ≥150mm, and twist coil ≥220.

[0009] (4) Selection of nickel anode and ammonia nickel plating solution: The selection criteria are as follows: the nickel anode contains 0.15% to 0.3% sulfur-containing nickel beads or nickel cakes; the ammonia nickel plating solution meets the following requirements: metallic nickel content ≥180g / L, pH=4.0-4.7, specific gravity ≥1.54 at 20℃, sulfate ≤100ppm, free ammonia ≤50ppm, and other metallic impurities ≤2ppm.

[0010] Fixation stage of diamond micro powder

[0011] (5) After the steel wire is laid out, the surface of the steel wire is cleaned. The cleaning includes physical cleaning and surface cleaning with weak acid and alkali.

[0012] (6) Abrasive fixing and video monitoring:

[0013] a. An automatic powder feeding device adds abrasive to a nickel sulfamate electroplating solution container. A filter is installed in the electroplating solution container, and a connected filter is installed outside the electroplating solution container. After the steel wire passes through the electroplating solution, diamond micro powder abrasive coated with nickel is attached and fixed to its surface, completing the abrasive coating process and becoming the blank material for the wire saw.

[0014] b. By capturing images and videos of the wire saw blank through video surveillance, the abrasive density 'a' per unit length is calculated using software based on the images and videos, i.e., the abrasive density;

[0015] c. Based on the steps, the abrasive density a and the designed abrasive density range N are obtained. min ~N max Compare the results to determine if the concentration of diamond micron abrasive powder in the electroplating solution needs to be adjusted. If adjustment is required, control the automatic abrasive adding device or filter in step a to adjust the concentration of abrasive powder in the electroplating solution, and dynamically monitor and adjust accordingly.

[0016] (7) Nickel plating thickening: The wire saw blank obtained in step (6) is put into the plating solution to add a plating layer on the surface of the blank. The plating layer thickness c is controlled to be able to bury the abrasive particle size of 1 / 3 ± 0.5 μm.

[0017] (8) Cleaning, air drying, and wire collection: The cleaning method is to wash with room temperature pure water. The cleaning liquid is deionized pure water with a conductivity of less than 10 μs / cm. After washing, the wires are dried by blowing them through a dry air-heating pipe.

[0018] (9) Wire diameter measurement: The wire diameter d is measured by laser video measurement using a vertically intersecting bidirectional method. The wire diameter d is compared with the abrasive density a and the nickel plating thickness c. The deviation in wire diameter is used to control the entire system from wire feeding to wire take-up. The wire diameter d is related to the abrasive density a and the nickel plating thickness c, and satisfies the following formula:

[0019] Wire diameter (d) μm = baseline wire diameter + coating thickness (c) × 2 + 1.68 × 10 -3 ×ac 2

[0020] The baseline wire diameter here is the diameter of the steel wire selected in step (3); if the wire diameter measured in this step deviates too much from the wire diameter calculated by the above formula, it indicates that there is a problem in the previous production steps, so all previous production steps are suspended for inspection.

[0021] Post-processing

[0022] (10) Place the wire saw after winding into a heat preservation device and keep it at high temperature for 4-12 hours, with a furnace temperature of 150℃-220℃;

[0023] (11) After the wire is unloaded, the blade is sharpened and then rewound to form a finished wire saw: Two or more cylindrical winding rollers are used. After the wire is unloaded, the wire saw passes around the cylindrical winding rollers multiple times. The sharpening stone is placed between the winding rollers. The wire saw passes through the stone and contacts the stone.

[0024] Preferably, the nickel sulfamate electroplating solution in step (6) contains nickel sulfamate, boric acid, and nickel chloride.

[0025] Preferably, in step (6), the steel wire vertically arranges the abrasive through the electroplating solution, and an external magnetic field controls the process. The plating solution flows in from the upper end of the vertical electroplating tube and flows out from the lower end. Multiple magnetic fields are stacked vertically around the vertical electroplating tube. The magnetic lines of each layer of magnetic field are arranged perpendicular to the direction of the steel wire, and the magnetic fields of adjacent layers are arranged in a cross pattern.

[0026] Preferably, in step (6), the abrasive density 'a' is calculated by taking 60 photos per unit time using video, and then calculating the average value of the abrasive density 'a' from those 60 photos; if 'a' < N... min Start the automatic feeding device to increase the micro powder content in the electroplating solution until a > N. min Then stop the automatic powder feeding device; if a ≥ N max Start the filter to reduce the powder content in the electroplating solution until a < N. max .

[0027] Preferably, in step (7), four vertically arranged multi-groove guide wheels are used for wiring. The wire starts from the bottom groove of the multi-groove guide wheel and wraps around the four guide wheels horizontally once. Then, it spirals upward layer by layer at equal intervals. After multiple layers of winding, it is led out from the upper groove of the last multi-groove guide wheel. A vertical wire mesh layer is formed between the four multi-groove guide wheels. Two symmetrical wire mesh layers pass through their respective electroplating tanks. Nickel anodes are provided on both sides of the electroplating tank. The nickel anodes are symmetrically arranged on both vertical sides of the wire mesh layer.

[0028] The beneficial technical effects of this invention are:

[0029] 1. The diamond micro-powder abrasive undergoes magnetic separation and acid washing to remove impurities, ensuring the bonding strength with the outer nickel-plated metal layer. This ultimately guarantees the bonding strength between the subsequent steel wire and the thickened layer. During the abrasive application process, due to the control of the magnetic field, the nickel-plated diamond micro-powder abrasive is adsorbed onto the steel wire substrate. Simultaneously, as the electrochemical reaction of the nickel plating proceeds, the nickel metal is more easily deposited and bonded on the surface of the steel wire and the diamond micro-powder abrasive, thereby fixing the adsorbed diamond micro-powder abrasive onto the steel wire substrate.

[0030] 2. The abrasive density 'a' of the diamond micronized abrasive powder on the steel wire after abrasive application is monitored in real time using images and videos. Feedback is used to control the abrasive feeding container to replenish the diamond micronized abrasive powder in the plating bath, or to control the filtration unit to filter the diamond micronized abrasive powder in the plating bath to reduce the abrasive density in the plating bath. This achieves closed-loop control of the first abrasive application step, ensuring the uniformity and stability of the abrasive application, while also initially controlling the stability of the wire diameter.

[0031] 3. During the nickel plating thickening process, the concentricity of the thickened layer on the steel wire and the continuous stability of its thickness are controlled. Before winding, the wire saw diameter *d* is measured using a laser method. Based on the mapping relationship between wire diameter *d*, abrasive density *a*, and plating thickness *c*, a secondary closed-loop control is implemented to control the entire wire saw production process. The two closed-loop controls operate nested together, ensuring precise control throughout the entire process. The diamond wire saw obtained using this method exhibits high continuous stability in various performance indicators, ensuring good process stability when cutting single-crystal silicon carbide substrates, thereby reducing cutting risks. Attached Figure Description

[0032] Figure 1 Flowchart of the manufacturing method of a diamond wire saw for cutting silicon carbide single crystal substrates;

[0033] Figure 2 A diagram showing the relationship between the magnetic field lines of the abrasive fixing unit and the vertical arrangement of the steel wires;

[0034] Figure 3 This is a specific magnetic field arrangement scheme in an embodiment of the present invention;

[0035] Figure 4 A top view of the wiring method during the nickel plating thickening process;

[0036] Figure 5 Side view of the wiring method in the nickel plating thickening process (without the electroplating tank);

[0037] In the diagram: 1. Steel wire, 2. Magnetic lines, 3. Electroplating tube, 4. Bar magnet, 5. Steel wire after sanding, 6. Multi-groove guide wheel, 7. Electroplating tank, 71. Nickel anode, 8. Wire mesh layer. Detailed Implementation

[0038] Example 1: See Figure 1-5 The figure shows a method for manufacturing a diamond wire saw for cutting silicon carbide single crystal substrates, characterized by comprising the following steps:

[0039] Material selection stage

[0040] (1) Diamond material selection: Select diamond rough with Ti not less than 70 and TTi not less than 65. Crush the diamond into micro-powder abrasive, and remove impurities through shaping and acid washing to ensure the bonding strength between the diamond abrasive and the nickel-plated metal, and ultimately ensure the bonding strength between the diamond abrasive and the steel wire using nickel metal. The diamond micro-powder is then graded by overflow method, with high grading accuracy. Different particle sizes correspond to different specifications of SiC cutting wire saws. The relevant index requirements after grading are as follows, including volume distribution span < 0.68, crystal form (Omec PIP8.1 particle image processor): average roundness > 0.9, and ash content < 0.05%.

[0041] (2) Pretreatment of diamond micro powder abrasive: The diamond micro powder is placed in a vacuum of 1.0×10⁻⁶. -3 -1.0×10 - 5 Vacuum treatment at 300-500℃ for 6-12 hours in a vacuum furnace of Pa reduces the difference between Ti and TTi in the diamond micropowder, which is beneficial to the stability of the raw material crushing performance at high temperature.

[0042] For example, when diamond powder with a D50 of 35 μm is placed in a vacuum of 8.92 × 10⁻⁶ m², -4 The diamond microparticles were vacuum-treated at 300℃ for 6 hours. The differences in Ti and TTi values ​​before and after the treatment are shown in Table 1.

[0043] Table 1

[0044]

[0045] For example, when diamond powder with a D50 of 30 μm is placed in a vacuum of 8.92 × 10⁻⁶ μm... -4The diamond micropowder was vacuum-treated at 350℃ for 8 hours. The differences in Ti and TTi values ​​before and after the treatment are shown in Table 2.

[0046] Table 2

[0047]

[0048] The diamond micropowder is then plated with nickel alloy metal, sequentially including electroless nickel plating and electroless nickel plating. The total nickel plating thickness of the outer layer of the diamond abrasive is required to be between 0.8 and 1.5 μm, with the mass ratio of electroless to electroless nickel plating controlled between 1.2 / 1 and 1.5 / 1. The surface of the diamond abrasive must be completely covered without any gaps in the plating, the coating must be dense and free of nodules, and the micropowder particles must not adhere to each other.

[0049] (3) Selection of steel wire: High carbon steel wire is selected, with a total diameter deviation of ±0.5μm, wire ellipticity ≤0.5μm, breaking force deviation ≤1N, coil diameter ≥150mm, and torsion coil ≥220 (200mm / 300 / 10N).

[0050] (4) Selection of nickel (anode) and ammonia nickel plating solution: The selection criteria are as follows: the nickel (anode) contains 0.15% to 0.3% sulfur-containing nickel beads or nickel cakes; the ammonia nickel plating solution meets the following requirements: metal (Ni) content ≥180g / L, pH=4.0-4.7, specific gravity (20℃) ≥1.54, sulfate ≤100ppm, free ammonia ≤50ppm, and other metal impurities ≤2ppm.

[0051] The settling stage of diamond micron abrasive

[0052] (5) After the steel wire is laid out, the surface of the steel wire is cleaned. The cleaning includes physical cleaning and surface cleaning with weak acid and alkali.

[0053] (6) Abrasive fixing and video monitoring:

[0054] a. An automatic powder-adding device adds abrasive to the nickel sulfamate electroplating solution container. The container is equipped with a filter, and an external filter connects to the container. After passing through the electroplating solution, the steel wire has diamond micro-powder abrasive adhering and fixed to its surface. When the switch is activated, the plating solution passes through the filter to remove excess diamond micro-powder abrasive. When the abrasive is fixed, an external magnetic field controls the plating solution to flow in from the top of the vertical electroplating tube and out from the bottom. The steel wire passes vertically along its central axis through the electroplating tube and the abrasive electroplating solution. Multiple vertically stacked magnetic fields surround the vertical electroplating tube, with the magnetic field lines of each layer arranged perpendicular to the direction of the steel wire, and adjacent layers arranged in an intersecting pattern. In this embodiment, each magnetic field layer is established by two bar magnets arranged in a straight line. The different magnetic ends of the two bar magnets are symmetrically arranged on both sides of the electroplating tube. When the steel wire passes through the nickel plating solution in the magnetic field region, the diamond micro-powder abrasive coated with nickel is adsorbed onto the steel wire substrate. Simultaneously, as the electrochemical reaction of nickel plating proceeds, nickel metal is continuously deposited on the surface of the steel wire and the diamond micro-powder abrasive, thereby fixing the adsorbed diamond micro-powder abrasive onto the steel wire substrate, completing the abrasive coating process. The magnets of adjacent magnetic fields are arranged in a 90° staggered pattern, and the same magnetic poles of the upper and lower layers are arranged in a spiral around the electroplating tube. Figure 2 , Figure 3 As shown, this multi-layered spiral magnetic field arrangement helps to achieve uniform fixation of diamond micro powder around the steel wire and along its length, thereby initially controlling the size stability of the wire saw blank and initially ensuring the quality of the wire saw.

[0055] The electroplating solution contains diamond micro-powder abrasive. Before entering the plating solution, the surface of the diamond micro-powder abrasive is treated and coated with a nickel layer. The diamond micro-powder abrasive coated with nickel has electrical conductivity and magnetism, which can be well concentrated around the steel wire by the arranged magnetic field during the abrasion process in the electroplating solution. At the same time, it can be easily coated onto the surface of the steel wire during the abrasion process in the electroplating solution, thus completing the abrasion process.

[0056] The nickel sulfamate electroplating solution consists of nickel sulfamate, boric acid, and nickel chloride. Nickel sulfamate is the main salt, providing the nickel metal ions required for nickel plating and also acting as a conductive salt. Boric acid is a buffer that maintains the pH of the plating solution within a certain range. Nickel chloride acts as an anodic activation agent.

[0057] b. By capturing images and videos of the wire saw blank through video monitoring, the abrasive density 'a' per unit length is calculated using software based on the images and videos; that is, the abrasive density, in this embodiment, 'a' is the number of abrasive particles per millimeter of length.

[0058] c. Based on the abrasive density a and the designed particle number range N min ~N maxCompare the results to determine if the concentration of diamond micron abrasive powder in the electroplating solution needs to be adjusted. If adjustment is required, control the automatic abrasive adding device or filter in step a to adjust the concentration of abrasive powder in the electroplating solution, and dynamically monitor and adjust accordingly.

[0059] The video captures 60 photos per unit time; calculate the average abrasive density 'a' from these 60 photos. If a < N min Start the automatic feeding device to increase the micro powder content in the electroplating solution until a > N. min Then stop the automatic powder feeding device; if a ≥ N max Start the filter to reduce the powder content in the electroplating solution until a < N. max .

[0060] (7) Nickel plating thickening: The wire saw blank obtained in step (6) is put into the plating solution to add a plating layer on the surface of the blank. The plating layer thickness c is controlled to be able to bury the abrasive particle size of 1 / 3 ± 0.5 μm. Nickel plating can increase the holding force of diamond micro powder particles. The nickel plating layer is combined with the steel wire surface to form an alloy. The diamond micro powder particles are wrapped by the plating layer and are not easy to fall off. This can maintain the stability of the cutting ability of the wire saw and extend the service life of the wire saw.

[0061] In step (7), four vertically arranged multi-groove guide wheels are used for wiring. The wire starts from the bottom groove of the multi-groove guide wheel, wraps horizontally around the four guide wheels once, and then spirals upwards at equal intervals layer by layer. After multiple layers of winding, it is led out from the upper groove of the last multi-groove guide wheel. A vertical wire mesh layer is formed between the four multi-groove guide wheels. Two symmetrical wire mesh layers pass through their respective electroplating tanks. Nickel anodes are set on both sides of the electroplating tanks, and the nickel anodes are symmetrically arranged on both vertical sides of the wire mesh layer, such as... Figure 4-5 As shown in the diagram, the wires can rotate axially after multiple passes around the rollers. The side of each layer of wire mesh facing the nickel anode changes as it enters the electroplating tank, ensuring that the plating layer grows evenly around the wire and that the plating layer has a uniform fixing ability to the diamond abrasive particles around it.

[0062] (8) Cleaning, air drying, and wire collection: The cleaning method is to wash with room temperature pure water. The cleaning solution is deionized pure water with a conductivity of less than 10 μs / cm. After washing, the wires are dried by blowing through a dry air-heating pipe.

[0063] (9) Wire diameter measurement: The wire diameter d is measured by laser video measurement using a vertically intersecting bidirectional method. The wire diameter d is compared with the abrasive density a and the nickel plating thickness c. The deviation in wire diameter is used to control the entire system from wire feeding to wire take-up. The wire diameter d is related to the abrasive density a and the nickel plating thickness c, and satisfies the following formula:

[0064] Wire diameter (d) μm = baseline wire diameter + coating thickness (c) × 2 + 1.68 × 10-3 ×ac 2

[0065] The baseline wire diameter here is the diameter of the steel wire selected in step (3). If the measured wire diameter deviates too much from the wire diameter calculated by the above formula, and the deviation is greater than 1.2%, it indicates that there is a problem in the previous production steps. Then, all previous production steps are suspended for inspection to see if the abrasive density detection is correct and if there is a problem in the nickel plating thickness control process. After solving the problem, production is restarted from step (1). This can avoid the problems generated in the previous process steps from being passed on to the end, so as to achieve overall closed-loop control. This closed-loop control forms a nested control with the closed-loop control of abrasive density in the previous sanding process, which ensures the stability of the wire saw production process and thus ensures the stability of quality.

[0066] Post-processing

[0067] (10) After the wire saw is wound up, put it into a heat preservation device and keep it at a high temperature for 4-12 hours. The furnace temperature is 150℃-220℃. This can reduce the brittleness of metal materials, including steel wire and coating, increase their toughness, and avoid the problem of brittle cracking and diamond micro powder particles falling off when the wire saw is used due to repeated bending of metal materials.

[0068] (11) After laying out the wire, sharpen the blade and rewind it a second time to obtain the finished wire saw:

[0069] Specifically, two or more cylindrical winding rollers are used. After the wire is unwound, the wire saw passes around the cylindrical winding rollers multiple times. The sharpening stone is placed between the winding rollers, and the wire saw contacts the stone when it passes the stone.

Claims

1. A method for manufacturing a diamond wire saw for cutting silicon carbide single crystal substrates, characterized in that, Includes the following steps: Material selection stage (1) Diamond material selection: Select diamond raw materials with Ti not less than 70 and TTi not less than 65, crush the diamond into micro abrasive powder, shape and acid wash, and classify the diamond micro abrasive powder by overflow method. The relevant index requirements after classification are as follows, including volume distribution span < 0.68, crystal form: average roundness > 0.9, ash content < 0.05%; (2) Pretreatment of diamond micro powder abrasive: The diamond micro powder abrasive is placed in a high vacuum of 1.0×10⁻⁶. -3 -1.0×10 - 5 Vacuum treatment at 300-500℃ for 6-12 hours in a vacuum furnace of PA; then, the diamond micro powder abrasive is plated with nickel alloy metal, including electroless nickel plating and electroplating. The total nickel plating thickness of the outer layer of the diamond micro powder abrasive is between 0.8-1.5μm, and the mass ratio of electroless nickel plating to electroplating nickel is controlled between 1.2 / 1 and 1.5 / 1. The surface of the diamond micro powder abrasive is completely covered without any missing plating, the coating is dense and without nodules, and the micro powder abrasive particles do not stick together. (3) Selection of steel wire: High carbon steel wire is selected, with a total diameter deviation of ±0.5μm, wire ellipticity ≤0.5μm, breaking force deviation ≤1N, coil diameter ≥150mm, and twist coil ≥220. (4) Selection of nickel anode and ammonia nickel plating solution: The selection criteria are as follows: the nickel anode contains 0.15% to 0.3% sulfur-containing nickel beads or nickel cakes; the ammonia nickel plating solution meets the following requirements: metallic nickel content ≥180g / L, pH=4.0-4.7, specific gravity ≥1.54 at 20℃, sulfate ≤100ppm, free ammonia ≤50ppm, and other metallic impurities ≤2ppm. Fixation stage of diamond micro powder (5) After the steel wire is laid out, the surface of the steel wire is cleaned. The cleaning includes physical cleaning and surface cleaning with weak acid and alkali. (6) Abrasive fixing and video monitoring: a. An automatic powder feeding device adds abrasive to a nickel sulfamate electroplating solution container. The electroplating solution container is equipped with a filter, and a connected filter is installed outside the electroplating solution container. After the steel wire passes through the electroplating solution, diamond micro powder abrasive coated with nickel is attached and fixed to its surface, completing the abrasive coating process and becoming the blank material for the wire saw. b. By capturing images and videos of the wire saw blank through video surveillance, the abrasive density 'a' per unit length is calculated using software based on the images and videos, i.e., the abrasive density; c. Based on the steps, the abrasive density 'a' is measured and its relationship with the designed abrasive density range 'N' is obtained. min ~N max Compare the results to determine if the concentration of diamond micron abrasive powder in the electroplating solution needs to be adjusted. If adjustment is required, control the automatic abrasive adding device or filter in step a to adjust the concentration of abrasive powder in the electroplating solution, and dynamically monitor and adjust accordingly. (7) Nickel plating thickening: The wire saw blank obtained in step (6) is put into the plating solution to add a plating layer on the surface of the blank. The plating layer thickness c is controlled to be able to bury the abrasive particle size of 1 / 3 ± 0.5 μm. (8) Cleaning, air drying, and wire collection: The cleaning method is to wash with room temperature pure water. The cleaning liquid is deionized pure water with a conductivity of less than 10 μs / cm. After washing, the wires are dried by blowing them through a dry air-heating pipe. (9) Wire diameter measurement: The wire diameter d is measured by laser video measurement using a vertically intersecting bidirectional method. The wire diameter d is compared with the abrasive density a and the nickel plating thickness c. The deviation in wire diameter is used to control the entire system from wire feeding to wire take-up. The wire diameter d is related to the abrasive density a and the nickel plating thickness c, and satisfies the following formula: Line diameter d = baseline line diameter + c × 2 + 1.68 × 10 -3 ×ac 2 The baseline diameter here is the diameter of the steel wire selected in step (3); If the wire diameter measured in this step deviates too much from the wire diameter calculated by the above formula, it indicates that there is a problem in the previous production steps. In this case, all previous production steps should be suspended for inspection. The abrasive density 'a' is the number of abrasive particles per millimeter of length. Post-processing (10) Place the wire saw after winding into a heat preservation device and keep it at high temperature for 4-12 hours, with a furnace temperature of 150℃-220℃; (11) After the wire is unloaded, the saw is sharpened and then wound up again to form the finished wire saw: Two or more cylindrical winding rollers are used. After the wire is unloaded, the wire saw passes around the cylindrical winding rollers multiple times. The sharpening stone is placed between the winding rollers. The wire saw passes through the stone and contacts the stone.

2. The method for manufacturing a diamond wire saw for cutting silicon carbide single crystal substrates according to claim 1, characterized in that: The nickel sulfamate electroplating solution in step (6) contains nickel sulfamate, boric acid, and nickel chloride.

3. The method for manufacturing a diamond wire saw for cutting silicon carbide single crystal substrates according to claim 1, characterized in that: In step (6), the steel wire vertically arranges the abrasive through the electroplating solution, and an external magnetic field controls the process. The plating solution flows in from the upper end of the vertical electroplating tube and flows out from the lower end. Multiple magnetic fields are stacked vertically around the vertical electroplating tube. The magnetic lines of each layer of magnetic field are arranged perpendicular to the direction of the steel wire, and the magnetic fields of adjacent layers are arranged in a cross pattern.

4. The method for manufacturing a diamond wire saw for cutting silicon carbide single crystal substrates according to claim 1, characterized in that: In step (6), the abrasive density 'a' is calculated by taking 60 photos per unit time using video, and then calculating the average value of the abrasive density 'a' from those 60 photos. If 'a' < N... min Start the automatic feeding device to increase the micro powder content in the electroplating solution until a > N. min Then stop the automatic powder feeding device; if a ≥ Nmax Start the filter to reduce the powder content in the electroplating solution until a < N. max .

5. The method for manufacturing a diamond wire saw for cutting silicon carbide single crystal substrates according to claim 1, characterized in that: In step (7), four vertically arranged multi-groove guide wheels are used for wiring. The wire starts from the bottom groove of the multi-groove guide wheel and wraps around the four guide wheels horizontally once. Then, it spirals upward layer by layer at equal intervals. After multiple layers of winding, it is led out from the upper groove of the last multi-groove guide wheel. A vertical wire mesh layer is formed between the four multi-groove guide wheels. The two symmetrical wire mesh layers pass through their respective electroplating tanks. Nickel anodes are set on both sides of the electroplating tank. The nickel anodes are symmetrically arranged on both sides of the vertical wire mesh layer.

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