Diamond loop wire for wafer cutting and preparation method thereof

Abstract

The invention provides a diamond loop wire for wafer cutting and a preparation method of the diamond loop wire. The diamond loop wire for wafer dicing includes a linear base material and a plurality of dicing portions. The linear base material is formed by twisting a plurality of alloy wires. The multiple cutting parts are arranged on the outer surface of the linear base material at intervals in the axial direction of the linear base material, and each cutting part comprises abrasive materials at least containing natural diamonds and artificial diamonds. The preparation method comprises the following steps: S1, coaxially twisting a plurality of alloy wires into a linear base material; s2, the linear base material is subjected to nickel pre-plating treatment, and a nickel pre-plating layer is formed in at least part of the area of the surface of the linear base material; and S3, an abrasive material at least containing artificial diamond and natural diamond is provided, and the abrasive material is fixed to the peripheral face of the linear base material through a composite electroplating technology. The diamond loop wire for wafer cutting provided by the invention has the advantages of wear resistance, high cutting efficiency and high cutting precision.

Description

Technical Field

[0001] This application relates to the fields of materials processing and cable manufacturing, and in particular to a diamond toroidal wire for wafer dicing and its preparation method. Background Technology

[0002] Diamond wire loop technology holds a crucial position in the semiconductor manufacturing industry. With the rapid development of the semiconductor industry, the demands for precision and efficiency in wafer dicing tools are increasing. As a key step in semiconductor manufacturing, wafer dicing directly impacts the performance and yield of semiconductor devices. High-precision dicing tools ensure more accurate wafer dicing or full dicing, thereby improving the quality and production efficiency of semiconductor products and driving the entire semiconductor industry towards higher performance and smaller dimensions.

[0003] In existing technologies, to achieve wafer dicing or full slicing, diamond toroidal wires with diamond as the cutting medium and toroidal metal wire as the substrate are typically used as cutting tools. Most existing cutting tools employ laser positioning methods, fabricated by directly fixing a single diamond abrasive grain onto the toroidal metal wire substrate.

[0004] However, existing diamond wire abrasives only use diamond grains and lack precise arrangement technology, making them prone to wear. Due to the poor self-sharpening properties of diamond wire rings, they are prone to failing to cut wafers, directly resulting in a short lifespan and reduced applicability. How to solve these technical problems is a question that those skilled in the art need to consider. Summary of the Invention

[0005] To address the aforementioned technical problems, this application provides a diamond toroidal wire for wafer dicing.

[0006] In one embodiment, the diamond wire loop for wafer dicing includes a wire-shaped base material and a plurality of dicing portions. The wire-shaped base material is formed by stranding multiple alloy wires. The plurality of dicing portions are spaced apart along the axial direction of the wire-shaped base material on its outer surface, and each dicing portion includes an abrasive containing at least natural diamond and synthetic diamond.

[0007] Understandably, the linear base material is composed of multiple strands of alloy wire, giving the diamond toroidal wire good tensile strength, torsional stiffness, and bending flexibility. This provides a robust and reliable base for the stable adhesion of subsequent cutting sections, preventing breakage of the linear base material. Multiple cutting sections are spaced apart along the axial direction of the linear base material, enabling effective chip removal and cooling during cutting, preventing slag accumulation and localized overheating, while ensuring that some sections can continue cutting even after a section detaches.

[0008] Natural diamonds typically possess high hardness and a sharp initial cutting edge, providing excellent cutting performance in the early stages of cutting; while synthetic diamonds generally have better toughness and a regular crystal shape, resulting in stronger wear resistance. Combining the two, leveraging the differences in their physical properties, creates differentiated wear during the cutting process. When the natural diamond wears down or falls off, the synthetic diamond continues to function, exposing new cutting edges. This synergistic effect enhances the self-sharpening properties of the diamond rings, preventing slippage caused by abrasive wear, thereby extending the lifespan of the diamond rings and ensuring the continuous stability of wafer dicing.

[0009] In one embodiment, the linear base material is divided into multiple cutting areas and multiple connecting areas along its axial direction. The cutting areas and connecting areas are arranged alternately and connected end to end. The multiple cutting parts are respectively located in the multiple cutting areas.

[0010] Understandably, by dividing the linear substrate into spaced-out cutting and connecting zones along the axial direction, the diamond wire loops alternately contact the workpiece with the cutting and non-cutting sections during high-speed wafer cutting. The connecting zones form a natural chip-carrying space, effectively removing silicon powder and other waste chips generated during cutting, preventing them from clogging the diamond wire loops and reducing cutting efficiency. Simultaneously, the connecting zones effectively lower the cutting temperature, preventing wire breakage or wafer chipping due to heat accumulation. Furthermore, the connecting zones optimize the utilization efficiency of the diamond abrasive grains in the cutting zone, contributing to improved overall flexibility of the diamond wire loops, reducing additional damage to the wafer surface, and further enhancing cutting quality and efficiency.

[0011] In one embodiment, each cutting portion is arranged in a continuous ring around the outer peripheral surface of the linear base material, and each cutting portion extends radially outward from the surface of the linear base material.

[0012] Understandably, each cutting section is designed as a continuous ring extending radially outward. This structure ensures that, regardless of the rotation angle of the diamond ring during wafer cutting, the cutting section can stably contact the wafer surface and effectively cut. The structural form of the cutting section provides uniform cutting force and abrasive utilization for the diamond ring. Simultaneously, the radially outward extension design ensures sufficient abrasive layer thickness, enhancing the durability and cutting performance of the cutting section and ensuring stability throughout the entire cutting process.

[0013] In one embodiment, the linear base material is formed by coaxially twisting multiple stainless steel wires and multiple tungsten wires, and the cutting part is provided on the outer surface of the twisted linear base material.

[0014] Understandably, stainless steel wire provides excellent flexibility and corrosion resistance for the wire-shaped base material, while tungsten wire provides high strength, stiffness, and tensile strength. The stranded structure of stainless steel and tungsten wires ensures that the wire-shaped base material has sufficient strength to resist tensile stress during cutting, while also maintaining its flexibility to meet the requirements of high-speed cutting and bending. This stranded structure, while ensuring the strength of the diamond toroidal wire, also enhances its toughness, guaranteeing the overall mechanical properties and stability of the diamond wire.

[0015] The embodiment also provides a method for preparing diamond wire loops for wafer dicing, comprising the following steps: Step S1, coaxially twisting multiple alloy wires into a wire-shaped base material. Step S2, pre-plating the wire-shaped base material with nickel to form a pre-plated nickel layer on at least a portion of the surface of the wire-shaped base material. Step S3, providing an abrasive comprising at least synthetic diamond and natural diamond, and fixing the abrasive to the outer peripheral surface of the wire-shaped base material by a composite electroplating process.

[0016] Understandably, by coaxially twisting multiple alloy wires into a linear base material, the linear base material acquires good strength and toughness. Pre-plating the linear base material with nickel, forming a pre-plated nickel layer on its surface, lays the foundation for the effective adhesion of subsequent synthetic and natural diamond abrasives, improving the adhesion of the diamond abrasive grains. By providing a mixed abrasive containing natural and synthetic diamonds, and using a composite electroplating process to fix the mixed abrasive onto the linear base material, the composite electroplating process can control the uniform distribution and embedding depth of the diamond mixed abrasive. These three steps are interdependent and closely coordinated, from strengthening the linear base material and optimizing the interface to the precise selection and control of the abrasive. This solves the problem of single abrasive in existing technologies and achieves a uniform and effective distribution of the composite abrasive. It addresses the issue of easy wear of diamond abrasives caused by single abrasives, and avoids the technical problems of severe wear, poor self-sharpening, short lifespan, and low applicability caused by a lack of precise distribution. This method can precisely control the bonding and distribution of abrasive, ensuring that the prepared diamond toroidal wire has excellent wear resistance and self-sharpening properties, thereby improving the cutting efficiency and service life of the diamond toroidal wire.

[0017] In one embodiment, multiple alloy wires are coaxially twisted into a linear base material, and an entire insulating tube is fitted onto the surface of the linear base material. The insulating tube is heated until it shrinks and adheres to the surface of the linear base material. The insulating tube corresponding to the position on the linear base material where diamond needs to be electroplated is scanned by a laser, and the corresponding insulating tube is melted away, exposing the surface of the linear base material.

[0018] Understandably, this solution provides a high-precision, high-efficiency local masking method for precisely controlling the electroplating position and range of the abrasive, thereby accurately defining the cutting and bonding areas. It solves the technical problem of the lack of precise arrangement of natural and synthetic diamond abrasives, ensuring the accuracy and consistency of the spacing between multiple cutting sections, improving the stability and repeatability of product performance, and optimizing the utilization efficiency of the abrasive.

[0019] In one embodiment, the abrasive material in the linear substrate is removed by carbonization at locations on the surface where electroplating of diamond mixed abrasive is not required, thereby exposing the surface of the linear substrate.

[0020] Understandably, laser correction can be used to correct any minor spillage or irregular areas of diamond mixed abrasive that may occur during the electroplating process, thereby achieving a more precise arrangement of the diamond mixed abrasive. This optimizes the arrangement of the diamond mixed abrasive, reduces irregular areas, and improves the yield and consistency of the diamond rings.

[0021] In one embodiment, step S1 includes: coaxially twisting four 304 stainless steel wires with three tungsten wires, maintaining a dynamic and consistent tension in each wire during the twisting process. The roundness and consistency of the twisted wire diameter are monitored in real time using a micron-level guide wheel and a laser diameter gauge to obtain a linear base material; the linear base material is then subjected to electrolytic polishing and ultrasonic cleaning.

[0022] Understandably, the four 304 stainless steel wires provide excellent corrosion resistance for the wire busbar, extending its storage and service life, while the three tungsten wires enable it to withstand tension forces far exceeding those of conventional wire saws. By coaxially twisting the four 304 stainless steel wires and three tungsten wires, the breaking strength of the wire busbar is enhanced, preventing it from breaking when cutting high-tension, large-sized workpieces. Simultaneously, the coaxial twisting ensures the integrity of the wire busbar structure after a period of use, preventing breakage due to metal fatigue during high-speed reciprocating operation or wafer cutting in reverse direction. Micron-level guide rollers and a laser diameter gauge ensure the roundness and consistency of the twisted wire busbar diameter, guaranteeing the uniformity of the subsequent pre-plated nickel layer and preventing tension concentration and wire breakage caused by uneven wire diameter. Meanwhile, the micron-level guide wheel and laser diameter gauge ensure that the prepared linear base material not only has uniform mechanical properties and excellent surface smoothness, but also eliminates defects and impurities on the surface of the linear base material, optimizes the adhesion quality of the subsequent pre-plated nickel layer and abrasive, and improves the overall strength, flexibility and cutting stability of the diamond toroidal wire.

[0023] In one embodiment, step S3 includes the following steps: S31, placing the abrasive and the pre-nickel-plated linear substrate in a nickel ion electroplating solution, wherein the abrasive comprises synthetic diamond and natural diamond in a 1:3 ratio. S32, pre-plating with a current of 0.6 amperes per square decimeter for 25 minutes to plate a nickel layer on the surface of the abrasive. S33, plating twice consecutively with a current of 0.15 amperes per square decimeter, each time for 60 minutes, moving the nickel-plated abrasive to the pre-nickel-plated layer of the linear substrate, and achieving a diamond particle embedding rate of 10% to 20% in the abrasive. S34, continuing electroplating with a current of 0.2 amperes per square decimeter to achieve a diamond particle embedding rate of approximately 55% in the abrasive.

[0024] Understandably, this solution uses a 1:3 ratio of synthetic diamond to natural diamond abrasive, ensuring that the abrasive grains continuously generate new cutting edges during wear. This solves the problem of poor self-sharpening properties of single abrasives leading to easy dulling, thus extending the abrasive's lifespan. Simultaneously, the diamond-mixed abrasive maintains a sharp cutting edge, improving its cutting sharpness, increasing effective cutting time, and boosting cutting speed by 15-25%. Electroplating not only ensures that the sharp edges of the diamond-mixed abrasive are consistently adhered to the surface of the linear wire, improving initial sharpness and cutting efficiency, but also facilitates the bonding between the diamond-mixed abrasive and the pre-plated layer of the linear wire. It also ensures optimal bonding strength between the abrasive and the pre-plated layer, with precise and controllable embedding depth. This effectively prevents premature detachment or excessive dulling of the diamond-mixed abrasive during use. Precise electroplating parameter control achieves a high balance between the durability and self-sharpening properties of the diamond wire, improving its cutting efficiency and lifespan.

[0025] In one embodiment, step S3 includes the following steps: S31. Place the abrasive and the pre-nickel-plated linear substrate in a nickel-ion electroplating solution. The abrasive consists of synthetic diamond and natural diamond in a 1:3 ratio. S32. Pre-plating for 25 minutes using a current of 0.6 amperes per square decimeter to plate a nickel layer onto the abrasive surface. S33. Place the S pole of a strong magnet above the linear substrate and the N pole of a strong magnet below the abrasive. Use magnetic force to move the abrasive to the pre-nickel-plated layer on the linear substrate. S34. Continue electroplating using a current of 0.2 amperes per square decimeter to achieve a diamond particle embedding rate of approximately 55% in the abrasive.

[0026] Understandably, a magnetic field can move magnetic diamond abrasive particles onto the pre-coating layer of the linear substrate, ensuring that the sharp edges of the diamond abrasive particles face outwards and are fixed to the surface of the coating. Magnetic force is used to keep the cutting edge or sharp corner of the diamond abrasive particles always pointing towards the workpiece. This ensures that the diamond abrasive particles are evenly distributed on the pre-coating layer of the linear substrate, thereby improving the cutting performance and service life of the diamond wire. It effectively avoids damage and breakage of the linear substrate caused by uneven load on the diamond wire and a sharp increase in cutting resistance due to diamond abrasive particle shedding, ensuring the reliability of long-term diamond wire cutting and improving production efficiency. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of the diamond ring wire for wafer dicing provided in the embodiments of this application.

[0028] Figure 2 This is a schematic diagram of the linear parent material of the insulating tube provided in the embodiments of this application.

[0029] Figure 3 This is a schematic cross-sectional view of the diamond ring wire for wafer dicing provided in an embodiment of this application.

[0030] Figure 4 This is a flowchart of a method for preparing diamond ring wires for wafer dicing provided in an embodiment of this application.

[0031] Explanation of reference numerals in the attached figures: 1. Linear base material; 11. Alloy wire; 12. Cutting area; 13. Connecting area; 14. Pre-plated nickel layer; 15. Insulating tube; 2. Cutting section. Detailed Implementation

[0032] The following is in conjunction with the appendix Figure 1 To be continued Figure 4 This application will be described in further detail below.

[0033] Example 1

[0034] Combination Figures 1 to 3 As shown, in one embodiment, the diamond wire for wafer dicing includes a wire-shaped base material 1 and a plurality of dicing portions 2. The wire-shaped base material 1 is formed by twisting together a plurality of alloy wires 11. The plurality of dicing portions 2 are spaced apart along the axial direction of the wire-shaped base material 1 on the outer surface of the wire-shaped base material 1, and the dicing portions 2 include an abrasive containing at least natural diamond and synthetic diamond.

[0035] In this embodiment, refer to Figure 1 and Figure 3The linear base material 1 is made of multiple alloy wires 11 twisted together, giving the diamond toroidal wire good tensile strength, torsional stiffness, and bending flexibility. This provides a solid and reliable base for the stable adhesion of the subsequent cutting sections 2, preventing the linear base material 1 from breaking. Multiple cutting sections 2 are spaced apart along the axial direction of the linear base material 1, enabling effective chip removal and cooling during cutting, preventing chip accumulation and localized overheating, and ensuring that some cutting sections 2 can continue cutting even after they detach.

[0036] The cutting section 2 can use a mixture of 25% synthetic diamond and 75% natural diamond abrasive. Natural diamond typically has high hardness and a sharp initial cutting edge, providing excellent cutting performance in the early stages of cutting; while synthetic diamond typically has better toughness and a regular crystal shape, resulting in stronger wear resistance. By using a mixture of the two, the differences in physical properties between natural and synthetic diamonds can create differentiated wear during the cutting process. When the natural diamond wears down or falls off, the synthetic diamond can still function and expose new cutting edges. This synergistic effect enhances the self-sharpening properties of the abrasive ring, preventing slippage caused by abrasive wear, thereby extending the lifespan of the diamond ring and ensuring the continuous stability of wafer cutting. The method of fixing the diamond abrasive by twisting steel wire into a linear base material 1, compared to fixing the diamond abrasive first and then twisting it into the linear base material 1, provides precise positioning of the diamond abrasive particles, which is beneficial for fixing the optimal cutting direction of the diamond abrasive particles.

[0037] In one embodiment, the linear base material 1 is formed by coaxially twisting multiple stainless steel wires and multiple tungsten wires, and the cutting part 2 is provided on the outer surface of the twisted linear base material 1.

[0038] In this embodiment, refer to Figure 1 and Figure 3 The multi-alloy wire 11 comprises four 304 stainless steel wires and three tungsten wires. The stainless steel wires provide the wire-shaped base material 1 with good flexibility and corrosion resistance, while the tungsten wires provide it with high strength, stiffness, and tensile strength. The stranded structure of the stainless steel and tungsten wires ensures that the wire-shaped base material 1 has sufficient strength to resist tensile stress during cutting, while also ensuring its flexibility to meet the requirements of high-speed cutting and bending. This stranded structure, while maintaining the strength of the diamond toroidal wire, also enhances its toughness, ensuring the overall mechanical properties and stability of the diamond wire.

[0039] In one embodiment, the linear base material 1 is divided into multiple cutting areas 12 and multiple connecting areas 13 along its axial direction. The cutting areas 12 and connecting areas 13 are arranged sequentially at intervals and connected end to end. Multiple cutting parts 2 are respectively provided in the multiple cutting areas 12.

[0040] In this embodiment, refer to Figure 1 and Figure 3 The cutting area 12 and the connecting area 13 are arranged alternately and connected end to end. All cutting areas 12 have equal lengths along the axial direction of the linear base material 1, while the connecting area 13 has a length ranging from 5 mm to 10 mm along the axial direction of the linear base material 1. By dividing the linear base material 1 into the spaced-apart cutting areas 12 and connecting areas 13 along the axial direction, the cutting portion 2 and the non-cutting portion alternately contact the workpiece when the diamond wire loop cuts the wafer at high speed. The connecting area 13 forms a natural chip-carrying space, which can promptly remove silicon powder and other waste chips generated during cutting, preventing these chips from clogging the diamond wire loop and reducing its cutting efficiency. Simultaneously, the presence of the connecting area 13 effectively reduces the cutting temperature, preventing wire breakage or wafer chipping due to heat accumulation. In addition, the presence of the connecting region 13 optimizes the utilization efficiency of the diamond abrasive grains in the cutting region 12, helps to improve the overall flexibility of the diamond ring, reduces additional damage to the wafer surface, and further improves the cutting quality and cutting efficiency.

[0041] In one embodiment, each cutting portion 2 is arranged in a continuous ring around the outer peripheral surface of the linear base material 1, and each cutting portion 2 extends radially outward from the surface of the linear base material 1.

[0042] In this embodiment, the inner wall of each cutting section 2 is fixedly connected to the outer peripheral surface of the linear base material 1, and each cutting section 2 extends radially outward from the surface of the linear base material 1 by the same distance. Each cutting section 2 is configured as a continuous ring extending radially outward. This structure ensures that, regardless of the rotation angle of the diamond ring during wafer cutting, the cutting section 2 can stably contact the wafer surface and perform effective cutting. The structural form of the cutting section 2 provides uniform cutting force and abrasive utilization for the diamond ring. Simultaneously, the radially outward extension design ensures sufficient abrasive layer thickness, enhancing the durability and cutting performance of the cutting section 2 and ensuring stability throughout the cutting process.

[0043] Compared to existing wire saws for cutting wafers, this diamond toroidal wire cutting process does not experience vibration or wire breakage. At the same time, it consumes less wire, reduces downtime caused by wire changes, and improves production efficiency.

[0044] The implementation principle of the diamond wire loop for wafer dicing in this embodiment is as follows: The diamond wire loop for wafer dicing is formed by twisting multiple alloy wires 11 together to form a linear base material 1, which improves the strength and wear resistance of the linear base material 1. Simultaneously, the dicing section 2 uses abrasives containing both natural and synthetic diamonds, fully utilizing the advantages of different types of abrasives to better adapt to the dicing requirements of wafers with different hardness and texture. The spacing and surrounding arrangement of the dicing section 2 makes the dicing process more uniform and efficient, with better self-sharpening properties. Compared with the prior art, this diamond wire loop for wafer dicing has the advantages of good self-sharpening properties and wear resistance.

[0045] Example 2

[0046] Further integration Figure 4 As shown in the embodiments of this application, a method for preparing diamond toroidal wires for wafer dicing is also provided, comprising the following steps: Step S1: Coaxially twist multiple alloy wires 11 into a linear base material 1.

[0047] Step S2: Perform pre-nickel plating on the linear base material 1 to form a pre-plated nickel layer 14 on at least a portion of the surface of the linear base material 1.

[0048] Step S3: Provide an abrasive containing at least synthetic diamond and natural diamond, and fix the abrasive to the outer peripheral surface of the linear base material 1 through a composite electroplating process.

[0049] In this embodiment, step S1 involves coaxially twisting multiple alloy wires 11 into a linear base material 1 on an ultra-precision micro-bundle stranding machine.

[0050] In this embodiment, step S1 includes: S11. An ultra-precision micro-bundle stranding machine can be used to coaxially strand four 304 stainless steel wires with three tungsten wires, maintaining dynamic consistency in the tension of each wire during the stranding process.

[0051] S12. Micron-level guide wheels and laser diameter measuring instruments are used to monitor the roundness and consistency of the stranded wire diameter in real time to obtain linear parent material 1.

[0052] S13. Electropolishing and ultrasonic cleaning are performed on the linear base material 1.

[0053] S14. The cleaned linear base material 1 is etched to remove the oxide layer, exposing the color of metallic nickel.

[0054] Understandably, the four 304 stainless steel wires provide excellent corrosion resistance for the wire busbar, extending its storage and service life. The three tungsten wires enable the wire busbar 1 to withstand tension forces far exceeding those of conventional wire saws. By coaxially twisting the four 304 stainless steel wires and three tungsten wires, the breaking strength of the wire busbar 1 is enhanced, preventing it from breaking when cutting high-tension, large-sized workpieces. Simultaneously, the coaxial twisting of the four 304 stainless steel wires and three tungsten wires ensures the integrity of the wire busbar structure after a period of use, preventing breakage due to metal fatigue during high-speed reciprocating operation or wafer cutting in reverse direction. Micron-level guide rollers and a laser diameter gauge ensure the roundness and consistency of the wire diameter of the twisted wire busbar 1, guaranteeing the uniformity of the subsequent pre-plated nickel layer 14 and preventing tension concentration and wire breakage caused by uneven wire diameter. Meanwhile, the micron-level guide wheel and laser diameter measuring instrument ensure that the prepared linear base material 1 not only has uniform mechanical properties and excellent surface smoothness, but also eliminates defects and impurities on the surface of the linear base material 1, optimizes the adhesion quality of the subsequent pre-plated nickel layer 14 and abrasive, and improves the overall strength, flexibility and cutting stability of the diamond ring.

[0055] In one embodiment, multiple alloy wires 11 are coaxially twisted into a linear base material 1, and then a whole insulating tube 15 is fitted onto the surface of the linear base material 1. The insulating tube 15 is heated until it shrinks and adheres to the surface of the linear base material 1. The insulating tube 15 corresponding to the location on the linear base material 1 where diamond electroplating is required is scanned by a laser, melting away the corresponding insulating tube 15 and exposing the surface of the linear base material 1.

[0056] In this embodiment, refer to Figure 1 and Figure 2 The inner wall of the entire insulating tube 15 is connected to the outer surface of the linear base material 1. A hot air gun can be used to heat the insulating tube 15 until it shrinks and adheres to the surface of the linear base material 1. The linear base material 1 with the insulating tube 15 fixed on it is then scanned with a laser at the locations on the linear base material 1 where diamond abrasive needs to be electroplated. The corresponding insulating tubes 15 are systematically melted away, exposing the surface of the linear base material 1. This provides a high-precision, high-efficiency local masking method for precisely controlling the electroplating position and range of the abrasive, thereby accurately defining the cutting area 12 and the connecting area 13. It solves the technical problem of the lack of precise arrangement of natural and synthetic diamond abrasives, ensuring the accuracy and consistency of the spacing of multiple cutting sections 2, improving the stability and repeatability of product performance, and optimizing the utilization efficiency of the abrasive.

[0057] In this embodiment, step S2 includes: Step S21, immersing the linear base material 1 in an electroplating solution. The electroplating solution can be a nickel sulfamate plating solution. Nickel sulfamate plating solution produces a coating with low internal stress, good ductility, and moderate hardness, making it particularly suitable for applications requiring a thicker coating while avoiding stress cracking. Step S22, applying current to the linear base material 1 until a pre-plated nickel layer 14 covers the surface of the linear base material 1. Step S3, providing an abrasive containing at least synthetic diamond and natural diamond, and fixing the abrasive to the outer peripheral surface of the linear base material 1 through a composite electroplating process.

[0058] Understandably, by coaxially twisting multiple alloy wires 11 into a linear base material 1, the linear base material 1 acquires good strength and toughness. Pre-plating the linear base material 1 with nickel and forming a pre-plated nickel layer 14 on its surface lays the foundation for the effective adhesion of subsequent synthetic and natural diamond abrasives, improving the adhesion of the diamond abrasive grains. By providing a mixed abrasive containing natural and synthetic diamonds and using a composite electroplating process to fix the mixed abrasive onto the linear base material 1, the composite electroplating process can control the uniform distribution and embedding depth of the diamond mixed abrasive. These three steps are interdependent and closely coordinated, from strengthening the linear base material 1 and optimizing the interface to the precise selection and control of the abrasive.

[0059] This technology solves the problem of using a single abrasive in existing technologies and achieves a uniform and effective arrangement of composite abrasives. It addresses the issue of easy wear of diamond abrasives due to a single abrasive, while avoiding the technical difficulties of severe wear, poor self-sharpening, short lifespan, and limited applicability caused by a lack of precise arrangement. It enables precise control of the bonding and distribution of abrasives, ensuring that the prepared diamond toroidal wires possess excellent wear resistance and self-sharpening properties, thus improving the cutting efficiency and service life of the diamond toroidal wires.

[0060] In one embodiment, step S1 includes: coaxially twisting four 304 stainless steel wires with three tungsten wires, maintaining a dynamic and consistent tension in each wire during the twisting process. The roundness and consistency of the twisted wire diameter are monitored in real time using a micron-level guide wheel and a laser diameter gauge to obtain a linear base material 1; the linear base material 1 is then subjected to electrolytic polishing and ultrasonic cleaning.

[0061] In one embodiment, step S3 includes the following steps: S31. The abrasive and the linear base material 1 of the pre-plated nickel layer 14 are placed in a nickel ion electroplating solution. The abrasive includes synthetic diamond and natural diamond in a ratio of 1:3.

[0062] S32. Pre-plating with a current of 0.6 amperes per square decimeter for 25 minutes to plate a nickel layer on the abrasive surface.

[0063] S33. Using a current of 0.15 amperes per square decimeter, plate twice continuously for 60 minutes each time, move the nickel-plated abrasive to the pre-plated nickel layer 14 of the linear base material 1, and make the embedding rate of diamond particles in the abrasive reach 10% to 20%.

[0064] S34. Continue electroplating using a current of 0.2 amperes per square decimeter to make the embedding rate of diamond particles in the abrasive reach approximately 55%.

[0065] In this embodiment, step S31 specifically includes: S311, using a three-dimensional mixer to mix a mixed diamond abrasive with synthetic diamond and natural diamond accounting for 25% and 75% respectively for a long time at low speed. S312, placing the abrasive and the linear base material 1 of the pre-plated nickel layer 14 in a nickel ion electroplating solution, and adding a conductive salt and a buffer. The conductive salt can be sodium chloride or sodium sulfate, and the buffer can be boric acid.

[0066] In this embodiment, the method further includes: step S35, rinsing the linear base material 1 with softened water and drying the rinsed linear base material 1. Step S36, the electroplating solution can be a nickel plating solution, and electroplating is performed at a current of 0.05 to 0.3 amperes per square decimeter for 3 to 15 minutes to generate a reinforced nickel film on the surface of the linear base material 1.

[0067] Understandably, the method for preparing diamond ring wire for wafer dicing provided in this application embodiment uses a 1:3 ratio of synthetic diamond and natural diamond abrasives, ensuring that the abrasive grains continuously generate new cutting edges during wear. This solves the problem of poor self-sharpening of single abrasives leading to easy dulling, and improves the service life of the abrasive. Simultaneously, the diamond mixed abrasive always maintains a sharp cutting edge, improving the cutting sharpness of the diamond mixed abrasive, increasing the effective cutting time, and increasing the cutting speed by 15-25%. The current electroplating method not only ensures that the sharp corners of the diamond mixed abrasive are uniformly adsorbed onto the surface of the linear matrix, improving initial sharpness and cutting efficiency, but also facilitates the bonding between the diamond mixed abrasive and the pre-plating layer of the linear matrix, achieving optimal bonding strength and precise controllable embedding depth. This effectively prevents premature detachment or excessive dulling of the diamond mixed abrasive during use. Precise electroplating parameter control enables a high balance between the durability and self-sharpening properties of diamond wire, improving the cutting efficiency and lifespan of diamond wire.

[0068] In another embodiment, step S3 includes the following steps: S31, placing the abrasive and the pre-plated nickel layer 14 of the linear substrate 1 in a nickel ion electroplating solution, wherein the abrasive comprises synthetic diamond and natural diamond in a ratio of 1:3. S32, pre-plating for 25 minutes using a current of 0.6 amperes per square decimeter to plate a nickel layer on the surface of the abrasive. S33, placing a strong magnet with an S pole above the linear substrate 1 and a strong magnet with an N pole below the abrasive, using magnetic force to move the abrasive to the pre-plated nickel layer 14 of the linear substrate 1. S34, continuing electroplating using a current of 0.2 amperes per square decimeter to achieve a diamond particle embedding rate of approximately 55% in the abrasive.

[0069] In this embodiment, step S31 includes: S311, mixing a mixture of synthetic diamond and natural diamond in a 25% and 75% ratio using a three-dimensional mixer at a low speed for a long time. S312, placing the abrasive and the pre-plated nickel layer 14 of the linear substrate 1 in a nickel ion electroplating solution, and adding a conductive salt and a buffer. The conductive salt can be sodium chloride or sodium sulfate, and the buffer can be boric acid. Step S35, rinsing the linear substrate 1 with softened water, and drying the rinsed linear substrate 1. Step S3, using a nickel plating solution, electroplating at a current of 0.05 to 0.3 amperes per square decimeter for 3 to 15 minutes to form a reinforced nickel film on the surface of the linear substrate 1.

[0070] Understandably, a magnetic field can move magnetic diamond abrasive particles to the pre-coating layer of the linear substrate 1, ensuring that the sharp edges of the diamond abrasive particles face outwards and are fixed to the surface of the coating. Magnetic force is used to keep the cutting edge or sharp corner of the diamond abrasive particles always facing the workpiece. This ensures that the diamond abrasive particles are evenly distributed on the pre-coating layer of the linear substrate 1, thereby improving the cutting performance and service life of the diamond wire. It effectively avoids damage and breakage of the linear substrate 1 caused by uneven load on the diamond wire and a sharp increase in cutting resistance due to diamond abrasive particle shedding, ensuring the reliability of long-term diamond wire cutting and improving production efficiency.

[0071] In another embodiment, the abrasive in the corresponding area of ​​the linear base material 1 is removed by carbonization by scanning the surface of the linear base material 1 with a laser at the location where the diamond mixed abrasive does not need to be electroplated, thus exposing the surface of the linear base material 1.

[0072] In this embodiment, refer to Figure 1The abrasive is fixed to the outer periphery of the linear base material 1. The surface of the linear base material 1 is scanned with a laser at locations where the diamond-mixed abrasive does not require electroplating. These locations are then systematically carbonized and removed, exposing the surface of the linear base material 1. This corrects any small overflows or irregular areas of diamond-mixed abrasive that may occur during the electroplating process, resulting in a more precise diamond-mixed abrasive arrangement. This method optimizes the arrangement of the diamond-mixed abrasive, reduces irregular areas, and improves the yield and consistency of the diamond ring wire. The implementation principle of the method for preparing diamond ring wire for wafer dicing in this embodiment is as follows: The preparation method of this embodiment, through reasonable steps and process parameter settings, fixes the abrasive containing natural and synthetic diamonds onto the linear base material 1. The multi-alloy wire 11 twisted into a linear base material 1 provides good support, pre-plating with nickel enhances the bonding force, and the composite electroplating process ensures effective fixation and a reasonable embedding rate of the abrasive. This preparation method can produce high-quality diamond toroidal wires for wafer dicing, which have good self-sharpening properties, improve the accuracy and efficiency of wafer dicing, and enhance the dicing effect.

[0073] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A diamond wire loop for wafer dicing, characterized in that, include: The linear base material (1) is made of multiple alloy wires (11) twisted together; Multiple cutting portions (2) are spaced apart on the outer surface of the linear base material (1) along the axial direction of the linear base material (1), and the cutting portions (2) include abrasives containing at least natural diamond and synthetic diamond.

2. The diamond wire loop for wafer dicing according to claim 1, characterized in that, The linear base material (1) is divided into multiple cutting areas (12) and multiple connecting areas (13) along its axial direction. The cutting areas (12) and the connecting areas (13) are arranged alternately and connected end to end. Multiple cutting parts (2) are respectively located in multiple cutting areas (12).

3. The diamond wire loop for wafer dicing according to claim 1, characterized in that, Each of the cutting portions (2) is arranged in a continuous ring around the outer peripheral surface of the linear base material (1), and each of the cutting portions (2) extends radially outward from the surface of the linear base material (1).

4. The diamond wire loop for wafer dicing according to claim 1, characterized in that, The linear base material (1) is formed by coaxially twisting multiple stainless steel wires and multiple tungsten wires, and the cutting part (2) is provided on the outer surface of the twisted linear base material (1).

5. A method for preparing diamond toroidal wire for wafer dicing, characterized in that, The method for preparing diamond wire loops for wafer dicing as described in any one of claims 1 to 4 comprises the following steps: Step S1: Coaxially twist multiple alloy wires (11) into the linear base material (1); Step S2: Perform a pre-plating nickel treatment on the linear base material (1) to form a pre-plated nickel layer (14) on at least a portion of the surface of the linear base material (1). Step S3: Provide the abrasive containing at least synthetic diamond and natural diamond, and fix the abrasive to the outer peripheral surface of the linear base material (1) by a composite electroplating process.

6. The method for preparing a diamond toroidal wire for wafer dicing according to claim 5, characterized in that: After multiple alloy wires (11) are coaxially twisted into the linear base material (1), an entire insulating tube (15) is fitted onto the surface of the linear base material (1). The insulating tube (15) is heated until it shrinks and adheres to the surface of the linear base material (1). The insulating tube (15) corresponding to the position on the linear base material (1) where diamond needs to be electroplated is scanned by laser, and the corresponding insulating tube (15) is melted off, exposing the surface of the linear base material (1).

7. The method for preparing a diamond toroidal wire for wafer dicing according to claim 5, characterized in that: By scanning the surface of the linear base material (1) with a laser at the location where the diamond mixed abrasive does not need to be electroplated, the abrasive in the corresponding area is removed by carbonization, exposing the surface of the linear base material (1).

8. The method for preparing a diamond toroidal wire for wafer dicing according to claim 5, characterized in that, The S1 step includes: coaxially twisting four 304 stainless steel wires and three tungsten wires together, maintaining dynamic consistency in the tension of each wire during the twisting process; using micron-level guide wheels and laser diameter measuring instruments to monitor the roundness and consistency of the twisted wire diameter in real time, thereby obtaining the linear base material (1); and performing electrolytic polishing and ultrasonic cleaning on the linear base material (1).

9. The method for preparing a diamond toroidal wire for wafer dicing according to claim 5, characterized in that, Step S3 includes the following steps: S31. The abrasive and the linear base material (1) of the pre-plated nickel layer (14) are placed in a nickel ion electroplating solution. The abrasive includes synthetic diamond and natural diamond in a ratio of 1:

3. S32. Pre-plating a nickel layer onto the abrasive surface using a current of 0.6 amperes per square decimeter for 25 minutes; S33. Using a current of 0.15 amperes per square decimeter, plate twice continuously for 60 minutes each time, move the nickel-plated abrasive to the pre-plated nickel layer (14) of the linear base material (1), and make the embedding rate of diamond particles in the abrasive reach 10% to 20%; S34. Electroplating is continued using a current of 0.2 amperes per square decimeter to make the embedding rate of diamond particles in the abrasive reach approximately 55%.

10. The method for preparing a diamond toroidal wire for wafer dicing according to claim 5, characterized in that, Step S3 includes the following steps: S31. The abrasive and the linear base material (1) of the pre-plated nickel layer (14) are placed in a nickel ion electroplating solution. The abrasive includes synthetic diamond and natural diamond in a ratio of 1:

3. S32. Pre-plating a nickel layer onto the abrasive surface using a current of 0.6 amperes per square decimeter for 25 minutes; S33. Place a strong magnetic S pole above the linear base material (1) and a strong magnetic N pole below the abrasive, and move the abrasive to the pre-plated nickel layer (14) of the linear base material (1) by magnetic force. S34. Electroplating is continued using a current of 0.2 amperes per square decimeter to make the embedding rate of diamond particles in the abrasive reach approximately 55%.

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