A brazed diamond dressing disc and a method of manufacturing the same

Abstract

This invention discloses a brazed diamond dressing disc and its manufacturing method, comprising the following steps: ceramic mold making and preparation, diamond selection, cleaning of the substrate, mold, and diamonds, brazing filler metal preparation, adhesive coating and diamond embedding, brazing filler metal coating and fixture application, vacuum brazing furnace processing, and post-processing. This invention employs vertex alignment, uses large-particle diamonds as raw materials, and arranges the diamonds in an orderly manner to ensure a reasonable diamond exposure height and spacing, increasing the number of working diamonds on the dressing disc. This improves the processing efficiency of the dressing disc, extends its service life, and reduces diamond concentration, thus lowering costs.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, specifically to a brazing diamond dressing disc and its manufacturing method. Background Technology

[0002] CMP (Chemical Mechanical Polishing) is a key process in semiconductor manufacturing to achieve global uniform planarization of wafers. The wafer manufacturing process mainly includes seven independent process flows: photolithography, etching, thin film growth, diffusion, ion implantation, chemical mechanical polishing, and metallization. As one of the key processes in wafer manufacturing, chemical mechanical polishing refers to the efficient removal of excess material and global nanoscale planarization of the wafer surface through the synergistic effect of chemical etching and mechanical polishing.

[0003] Because integrated circuit components currently employ multi-layered, three-dimensional wiring, the front-end processes in integrated circuit manufacturing require multiple cycles. During this process, wafer planarization (CMP) technology is needed to achieve the planarization of the wafer surface. Simply put, if we compare chip manufacturing to building a high-rise building, each floor needs to be sufficiently flat and even before another floor can be built on top; otherwise, the surface will be uneven, affecting overall performance and reliability. CMP is a key process technology that effectively achieves nanometer-level global planarity across the "floors" of integrated circuits.

[0004] CMP (Chemical Mechanical Polishing) requires consumables such as polishing fluid, polishing pads, dressing discs, and cleaning fluid. Among these, the dressing disc is crucial for CMP, controlling the contact area between the wafer and the polishing pad to create appropriately sized and evenly distributed fluff on the pad surface. The distribution of the dressing disc's apex height controls the depth of diamond penetration into the polishing pad, influencing various CMP performance characteristics and making it a key consumable for controlling CMP performance. Traditional dressing disc processes use a stand-up alignment method to align diamonds. Although this method results in a large number of diamonds being planted, the actual number of working diamonds is only about 1%, approximately 300 to 500, and the diamonds are small, leading to unstable operation.

[0005] To this end, a method for manufacturing a nanomaterial-modified brazed chemical mechanical polishing pad diamond dressing disc is provided, which employs a new improved brazing process and a reverse casting process. Summary of the Invention

[0006] The purpose of this invention is to provide a nanomaterial-improved brazing chemical mechanical polishing pad diamond dressing disc and its manufacturing method to solve the above-mentioned problems.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a method for manufacturing a brazed diamond dressing disc, characterized in that it includes the following steps: a ceramic mold making and preparation step, a diamond selection step, a cleaning step of the substrate, the mold, and the diamond, a brazing filler metal making step, an adhesive coating and diamond embedding step, a brazing filler metal adhesive coating and fixture application step, a vacuum brazing furnace processing step, and a post-processing step.

[0008] (1) Steps for making and preparing ceramic molds: Based on the arrangement of diamond points and the spacing of diamonds, make a new mold or prepare an existing mold.

[0009] (2) Diamond selection steps: Use a diamond sorting machine to screen, classify and mark 55-65 mesh diamonds, and select diamonds with a height between 0.25-0.30mm, and diamonds with a single crystal morphology and (111) crystal faces for subsequent processing.

[0010] (3) Cleaning steps for the substrate, mold, and diamond:

[0011] (3.1) The required stainless steel diamond dressing disc substrate is prepared by machining and the dressing disc substrate is cleaned to remove oil and rust.

[0012] (3.2) Acid and alkali purification treatment is performed on ceramic molds and diamonds with (111) crystal faces;

[0013] (4) Steps for making brazing filler metal:

[0014] (4.1) A copper-based brazing filler metal is prepared by mixing Al, Cu, Ni, Cr and Ti in a mass ratio of 60%-75%:5%-10%:10%-20%:2%-4%:1%-10%, and the mixture is uniformly mixed to obtain mixture C;

[0015] (4.2) Mixture C and adhesive are mixed in a weight ratio of 1:1-4 to prepare a brazing filler slurry;

[0016] (5) Adhesive coating and diamond implantation steps:

[0017] (5.1) Apply acrylate pressure-sensitive adhesive to the ceramic mold in step 1 as an adhesive layer for diamond;

[0018] (5.2) Using a point drilling machine, diamonds with (111) crystal faces after cleaning in step 3 are orderly planted on a ceramic mold according to the design pattern and point spacing. At the same time, the diamond tips are controlled to face downwards, the diamond tilt angle is between 50° and 60°, and the diamond tough ends are oriented and consistent.

[0019] (6) Coating of solder adhesive and application of fixtures

[0020] (6.1) The brazing filler metal obtained in step 4 is uniformly coated onto the diamond dressing disc substrate after degreasing, derusting and cleaning in step 3. The coating height range is 25%-30% of the average height of the diamond abrasive grains, that is, the coating height is controlled between 0.05 and 0.1 mm.

[0021] (6.2) The substrate obtained in step 6.1 is flipped onto the ceramic mold on which diamonds were implanted in step 5.2, forming a sequence in which the upper layer is the trimmed stainless steel substrate, the middle layer is diamonds, and the bottom layer is the ceramic mold.

[0022] (6.3) Use a clamp to clamp the blank obtained in step 6.2 to ensure that the exposed height of diamond between the substrate and the ceramic mold is controlled at 0.2mm and the top is flush, thus completing the reverse casting process;

[0023] (7) Processing steps using a vacuum brazing furnace

[0024] A vacuum furnace was used to evacuate the system to a vacuum level of 10. -3 Pa~10 -6 Pa, the preliminary blank obtained in step 6 is heated to a brazing temperature of 1000℃-1200℃ and brazed for 3-5 minutes. Then, nitrogen containing 10%-30% ammonia is introduced to treat the surface of the weldment and the furnace is cooled. The nitrogen pressure range is 10Pa to 50Pa.

[0025] (8) Post-processing steps: Perform post-processing to obtain the finished diamond dressing disc.

[0026] Furthermore, in the mold making or preparation process, if the mold is to be remade, the following steps are included:

[0027] (1.1) Alumina, zirconium oxide, magnesium oxide and calcium oxide are used as raw materials, and the mass ratio range is 80%-95%: 2%-5%: 1%-4%: 2%-5%. After being mixed evenly, mixture A is obtained.

[0028] (1.2) Mixture A with a thermally conductive additive composed of carbon nanotubes and graphene sheets in a certain ratio, with the addition mass range controlled between 2% and 5%, to obtain mixture B;

[0029] (1.3) The mixture B is introduced into the mold for molding. The pressure range is controlled within 100-200MPa. Then, the pattern is designed on the surface of the mold. The pattern involves the arrangement of diamond points and the spacing of diamonds. Depending on the different process requirements and different polishing pads, the spacing of diamonds is controlled between 1 and 2 mm.

[0030] (1.4) Finally, inject an inert atmosphere such as nitrogen or rare gas, and sinter at 1400-1800℃ to obtain an alumina ceramic mold.

[0031] Further, in the steps of (6.1) coating of brazing filler metal and using a fixture, the brazing filler metal is uniformly coated on the diamond dressing disc substrate, and the coating height is controlled between 0.05-0.1 mm.

[0032] Further, (1) in the ceramic mold making or preparation step, the raw material components include alumina, zirconium oxide, magnesium oxide, calcium oxide and thermally conductive additives, with a mass ratio of 90%:3%:2%; 2%:3%; (2) in the ceramic mold making and preparation step, diamond with a specification of 60 mesh is screened.

[0033] (4) In the process of making brazing filler metal, the raw materials of copper-based brazing filler metal are Cu, Al, Ni, Cr and Ti, with a mass ratio of 64%:6%:20%:2%:8%, which are mixed evenly to obtain mixture C; mixture C is mixed with acrylic pressure-sensitive adhesive in a weight ratio of 1:3 to prepare brazing filler metal solution.

[0034] (6) In the steps of applying the brazing filler metal and using the fixture, the thickness of the applied brazing filler metal is 28% of the average height of the diamond abrasive grains, ensuring that the exposed height of the diamond between the substrate and the ceramic mold is controlled at 0.2 mm; (7) In the step of processing with a vacuum brazing furnace, a vacuum furnace is used to evacuate to a vacuum state with a vacuum degree of 10. -3 Pa, the preliminary blank obtained in step 6 is heated to 1020℃ and held for 5 minutes. Nitrogen gas containing ammonia is introduced to perform surface treatment on the weldment and then cooled with the furnace. The ammonia ratio is controlled at 15%, and the nitrogen pressure is maintained at 10Pa.

[0035] Further, (1) in the ceramic mold making or preparation step, the raw material components include alumina, zirconium oxide, magnesium oxide, calcium oxide and thermally conductive additives, with a mass ratio of 85%:4%:3%; 3%:4%; (2) in the ceramic mold making and preparation step, diamond with a specification of 65 mesh is screened.

[0036] (4) In the process of making brazing filler metal, the raw materials for copper-based brazing filler metal are Cu, Al, Ni, Cr and Ti, with a mass ratio of 60%:5%:25%:3%:7%, which are mixed evenly to obtain mixture C; mixture C is mixed with acrylic pressure-sensitive adhesive at a weight ratio of 1:2.5 to prepare brazing filler metal solution.

[0037] (6) In the steps of applying the brazing filler metal and using the fixture, the thickness of the applied brazing filler metal is 28% of the average height of the diamond abrasive grains, ensuring that the exposed height of the diamond between the substrate and the ceramic mold is controlled at 0.2 mm; (7) In the step of processing with a vacuum brazing furnace, a vacuum furnace is used to evacuate to a vacuum state with a vacuum degree of 10. -4 Pa, the preliminary blank obtained in heating step 6 is heated to 1040℃ and held for 4 minutes. Nitrogen gas containing ammonia is introduced to perform surface treatment on the weldment and then cooled with the furnace. The ammonia ratio is controlled at 20%, and the nitrogen pressure is maintained at 10Pa.

[0038] Further, (1) in the ceramic mold making or preparation step, the raw material components include alumina, zirconium oxide, magnesium oxide, calcium oxide and thermally conductive additives, with a mass ratio of 90%:2%:3%; 2%:3%; (2) in the ceramic mold making and preparation step, diamond with a specification of 70 mesh is screened.

[0039] (4) In the process of making brazing filler metal, the raw materials for copper-based brazing filler metal are Cu, Al, Ni, Cr and Ti, with a mass ratio of 70%:8%:18%:2%:2%, which are mixed evenly to obtain mixture C; mixture C is mixed with acrylic pressure-sensitive adhesive at a weight ratio of 1:3.5 to prepare brazing filler metal solution.

[0040] (6) In the steps of applying the brazing filler metal and using the fixture, the thickness of the applied brazing filler metal is 28% of the average height of the diamond abrasive grains, ensuring that the exposed height of the diamond between the substrate and the ceramic mold is controlled at 0.2 mm; (7) In the step of processing with a vacuum brazing furnace, a vacuum furnace is used to evacuate to a vacuum state with a vacuum degree of 10. -5 Pa, the preliminary blank obtained in heating step 6 is heated to 1050℃ and held for 3 minutes. Nitrogen gas containing ammonia is introduced to perform surface treatment on the weldment and then cooled with the furnace. The ammonia ratio is controlled at 25%, and the nitrogen pressure is maintained at 10Pa.

[0041] Further, the post-processing steps are as follows: remove the clamps, the adhesive loses its adhesiveness under high temperature, and the diamond dressing disc naturally separates from the ceramic mold; clean the diamond dressing disc with acetone solution, and then rinse it with distilled water; after taking it out, dry it in an oven to obtain the finished diamond dressing disc.

[0042] A nanomaterial-modified brazed chemical mechanical polishing pad diamond dressing disc, characterized in that it comprises diamond, a substrate and a brazing filler metal, wherein the diamond is brazed onto the substrate by the brazing filler metal, and the nanomaterial-modified brazed chemical mechanical polishing pad diamond dressing disc is manufactured by the method described in any one of the preceding claims.

[0043] Compared with the prior art, the beneficial effects of the present invention are:

[0044] This invention employs vertex alignment, uses large-particle diamonds as raw materials, and arranges the diamonds in an orderly manner to ensure a reasonable diamond exposure height and spacing. It uses an improved brazing filler metal for welding and a reverse casting method to increase the number of working diamonds in the dressing disc. This not only improves the processing efficiency of the dressing disc and extends its service life, but also reduces the diamond concentration and lowers costs. Attached Figure Description

[0045] Figure 1 This is a schematic diagram of an embodiment of the present invention;

[0046] Figure 2 This is a schematic plan view of the manufacturing process method according to an embodiment of the present invention;

[0047] Figure 3 Performance table of diamond dressing disc according to embodiments of the present invention;

[0048] Figure 4 Table showing the lifespan of polishing pads for samples from embodiments and comparative examples of the present invention;

[0049] In the diagram: 1-Soldering alloy, 2-Fixing fixture, 3-Diamond, 4-Acrylic pressure-sensitive adhesive, 5-Alumina ceramic mold, 6-Stainless steel substrate. Detailed Implementation

[0050] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0051] Please see Figure 1-4 The present invention provides a technical solution: a method for manufacturing a brazed diamond dressing disc, characterized by comprising the following steps:

[0052] (1) Steps for making and preparing ceramic molds

[0053] (1.1) Alumina, zirconium oxide, magnesium oxide and calcium oxide are used as raw materials, and the mass ratio range is 80%-95%: 2%-5%: 1%-4%: 2%-5%. After being mixed evenly, mixture A is obtained.

[0054] (1.2) Mixture A with a thermally conductive additive composed of carbon nanotubes and graphene sheets in a certain ratio, with the addition mass range controlled between 2% and 5%, to obtain mixture B; it can also be other thermally conductive additives, such as thermally conductive additives composed of carbon nanotubes and carbon fibers, carbon nanotubes and graphite, carbon nanotubes and carbon black, carbon nanotubes and alumina, carbon nanotubes and boron nitride, carbon nanotubes and silicon carbide, etc. 2%-5% is the range of the ratio of thermally conductive additives in the mass ratio of thermally conductive additives to mixture A;

[0055] (1.3) The mixture B is introduced into the mold for molding. The mold is a 4.25-inch round mold, but it can be other shapes. If it is a round mold, its diameter should be controlled within 10.8 cm (4.25 inches). If it is a square mold, its side length should be controlled within the range of 12-13 cm. The pressure range should be controlled within 100-200 MPa. Then, the pattern design is carried out on the surface of the 4.25-inch round mold or the square mold with a side length of 12-13 cm using screen printing technology. The pattern involves the arrangement of diamond points and the spacing of diamonds. According to different process requirements and different polishing pads, the spacing of diamonds is controlled between 1 and 2 mm to better control the distribution optimization of diamonds. The mold doesn't necessarily have to be circular; it can also be cylindrical, with a diameter of 10.8cm and a height of 1cm-2cm; or square, with a side length of 12-13cm and a thickness of 1cm-2cm. The introduced mixture B is molded into a cylindrical shape with a diameter of 10.8cm and a height of 1cm-2cm; or, if molded into a square shape, with a side length of 12-13cm and a thickness of 1cm-2cm. Patterns can also be designed on the mold surface using processes such as 3D printing or inkjet printing. The pattern design refers to the arrangement of the diamonds, which can be circular or radial, etc., to achieve the arrangement of diamonds at specific intervals and positions.

[0056] (1.4) Finally, an inert atmosphere such as nitrogen or rare gas is injected, and the mixture is sintered at 1400-1800℃ to obtain an alumina ceramic mold. The alumina ceramic mold is made by molding mixture B within the mold. The alumina ceramic mold is a slightly thick circular piece. Unless a new pattern design is required, the alumina ceramic mold can be reused. If a new diamond distribution arrangement is required, a new pattern design is needed, which means a new alumina ceramic mold needs to be made.

[0057] (2) Steps for selecting diamonds or diamonds

[0058] Diamonds of 55-65 mesh were screened, classified and marked using a diamond sorting machine. Diamonds with a height between 0.25 and 0.30 mm and a single crystal morphology with (111) crystal faces were selected for subsequent processing.

[0059] (3) Cleaning steps for the substrate, mold, and diamond.

[0060] (3.1) The required stainless steel diamond dressing disc substrate is prepared by machining and the dressing disc substrate is cleaned to remove oil and rust; the diameter of the stainless steel diamond dressing disc substrate is 10.8cm and the thickness is 6.5mm, which can also be adjusted as needed;

[0061] (3.2) Acid and alkali purification treatment is performed on ceramic molds and diamonds with (111) crystal faces.

[0062] (4) The process of making the brazing filler metal is as follows: other commercially available brazing fillers are not suitable; the brazing filler metal mentioned in this application needs to be made on-site.

[0063] (4.1) A copper-based brazing filler metal was prepared by mixing Al, Cu, Ni, Cr and Ti in a mass ratio of 60%-75%:5%-10%:10%-20%:2%-4%:1%-10%. The mixture was uniformly mixed using a ball mill to obtain mixture C.

[0064] (4.2) Mixture C and adhesive are mixed in a weight ratio of 1:1-4 to prepare a brazing filler slurry; the adhesive is a solution or gel-like adhesive such as pressure-sensitive adhesive or QIS-3033 adhesive to prepare the brazing filler slurry;

[0065] (5) Coating of acrylic pressure-sensitive adhesive and diamond embedding steps

[0066] (5.1) Apply acrylate pressure-sensitive adhesive to the alumina ceramic mold in step 1 as an adhesive layer for diamond; other adhesives besides acrylate pressure-sensitive adhesive can be used in this invention, such as QIS-3033 glue.

[0067] (5.2) Using a spot drilling machine, diamonds with (111) crystal faces after cleaning in step 3 are systematically planted on a ceramic mold according to the design pattern and the spacing between the spots. At the same time, the diamond tips are controlled to face downwards, the diamond tilt angle is between 50° and 60°, and the diamond tough ends are oriented and consistent. The ceramic mold here is the one made in step one. The mold already has a design pattern. The diamonds are arranged according to the design pattern on the ceramic mold using a spot drilling machine.

[0068] (6) Coating of brazing filler metal and reverse casting using a fixture

[0069] (6.1) The brazing filler metal obtained in step 4 is uniformly coated onto the diamond dressing disc substrate after degreasing, derusting and cleaning in step 3. The coating height range is 25%-30% of the average height of the diamond abrasive grains, that is, the coating height is controlled between 0.05 and 0.1 mm.

[0070] (6.2) The substrate obtained in step 6.1 is flipped onto the ceramic mold on which diamonds were implanted in step 5.2. This allows each diamond to be held by brazing filler metal, reducing the chance of diamonds falling off, and forming a sequence of upper layer being the trimmed stainless steel substrate, middle layer being diamonds, and bottom layer being the ceramic mold.

[0071] (6.3) Use a clamp to clamp the blank obtained in step 6.2, ensuring that the exposed diamond height between the substrate and the ceramic mold is controlled at 0.2mm (also 0.2mm in Example 1, and the same as in Examples 2-3, which is also 0.2mm), and that the diamond apex is flush, thus completing the reverse casting process. Figure 2 As shown, the exposed diamond height refers to the height between the top of the diamond 3 and the top of the solder adhesive layer 1, excluding the height of the diamond 3 extending into the solder adhesive layer 1; or the height between the acrylic pressure-sensitive adhesive 4 and the solder adhesive layer 1.

[0072] (7) Processing steps using a vacuum brazing furnace

[0073] A vacuum furnace was used to evacuate the system to a vacuum level of 10. -3 Pa~10 -6 Pa, the preliminary blank obtained in step 6 is heated to a brazing temperature of 1000℃-1200℃ and brazed for 3-5 minutes. Then, nitrogen gas containing 10%-30% ammonia is introduced to treat the surface of the weldment and it is cooled with the furnace. The nitrogen gas pressure range is 10Pa to 50Pa. The preliminary blank is heated in a vacuum brazing furnace.

[0074] (8) Post-processing steps

[0075] After removing the clamps, the acrylic pressure-sensitive adhesive loses its adhesiveness at high temperatures, causing the diamond dressing disc to naturally separate from the ceramic mold. The diamond dressing disc is then cleaned once with acetone solution, followed by rinsing with distilled water. After removal, it is dried in an oven to obtain the finished diamond dressing disc. The final product consists only of the diamond, the substrate, and the solder; the diamond is soldered onto the substrate using the solder.

[0076] This invention uses vertex alignment, large diamond particles (referring to diamonds on the (111) facet) as raw materials, and arranges the diamonds in an orderly manner. It adopts the reverse casting method to ensure a reasonable diamond exposure height and reasonable spacing, thereby increasing the number of working diamonds on the dressing disc. This not only improves the processing efficiency of the dressing disc, but also extends the service life of the dressing disc, while reducing the diamond concentration and lowering the cost.

[0077] Example 1

[0078] A method for manufacturing a diamond dressing disc for a brazing chemical mechanical polishing pad improved with nanomaterials includes the following steps:

[0079] (1) Making ceramic molds

[0080] (1.1) The raw material components include alumina, zirconium oxide, magnesium oxide, calcium oxide and thermally conductive additives, with a mass ratio of 90%:3%:2%; 2%:3%. First, alumina, zirconium oxide, magnesium oxide and calcium oxide are uniformly mixed using a ball mill with a ball-to-material ratio of 5:1 and a ball mill speed of 150 rpm. The mixture is mixed for 2 hours at a temperature <50℃ to obtain mixture A. The ball-to-material ratio refers to the mass ratio of the ball mill to the raw material. The ball mill speed range is 100 rpm-150 rpm, preferably 150 rpm.

[0081] (1.2) Add the thermal conductive additive to mixture A and mix it evenly using a ball mill with a ball-to-material ratio of 6:1 and a rotation speed of 200 rpm. Mix for 1 hour at a temperature <50℃ to obtain mixture B.

[0082] (1.3) Mixture B is introduced into a 4.25-inch circular mold for molding. The pressure range is controlled within 100-200MPa. After molding, a pattern design is made on the surface of the mold using screen printing. Then, it is placed in an atmosphere sintering furnace and injected with an inert atmosphere such as nitrogen or rare gas atmosphere. The mold is sintered at 1500℃ to obtain an alumina ceramic mold.

[0083] (2) Diamond selection

[0084] Diamonds with a specification of 60 mesh are screened using a diamond sorting machine. Diamonds with a single-row crystal morphology are selected, and diamonds with (111) facets are selected. The number of diamonds used in each dressing disc is not less than 2500, that is, not less than 2500 diamonds are screened.

[0085] (3) Cleaning of the substrate, mold, and diamond.

[0086] (3.1) Select a diamond dressing disc substrate made of 316 stainless steel. Perform pretreatment on the substrate in the order of grinding, alkaline washing, acid washing, activation, cleaning and drying. The purpose is to remove the oxide layer, fatigue layer or oil stains on the surface of the substrate and eliminate any possible adverse effects.

[0087] (3.2) Perform pretreatment on the alumina ceramic mold obtained in step 1 according to step 3.1; perform pretreatment on the alumina ceramic mold in the order of cleaning and drying;

[0088] (3.3) The diamond obtained in step 2 is pretreated by a combination of magnetic separation and acid-base treatment to remove any metal elements and metal compound impurities that may be present, thereby weakening the inherent weak magnetic properties of the diamond particles. Simultaneously, this process removes any oil residue that may have accumulated on the surface of the diamond particles, improving their wettability. Magnetic separation and acid-base treatment are existing methods for treating diamond, with magnetic separation preceding acid-base treatment.

[0089] (4) Preparation of brazing filler metal

[0090] (4.1) The raw materials for copper-based brazing filler metal are Cu, Al, Ni, Cr, and Ti, with a mass ratio of 64%:6%:20%:2%:8%. They are uniformly mixed using a ball mill at a ball-to-material ratio of 5:1 and a rotation speed of 150 rpm for 2 hours at a temperature <50℃ to obtain mixture C.

[0091] (4.2) Mix mixture C with acrylic pressure-sensitive adhesive to prepare a soldering solution. Mix the solution at a weight ratio of 1:3 using a magnetic stirrer at a speed of 500 rpm for 30 minutes to prepare the soldering solution.

[0092] (5) Coating of acrylic pressure-sensitive adhesive and diamond embedding

[0093] (5.1) Place the alumina ceramic mold from step 1 on a rotating coating table and uniformly coat the alumina ceramic mold with acrylic pressure-sensitive adhesive as an adhesive layer for diamond.

[0094] (5.2) Place the mold obtained in 5.1 on the fixed fixture, and then use a spot drill to orderly plant the diamonds with (111) crystal faces after cleaning in step 3 according to the circular design pattern of the alumina ceramic mold, and ensure that the tough ends of the diamonds are oriented in a consistent manner, wherein the tilt angle of the diamonds is controlled to be 55°.

[0095] (6) Coating of brazing filler metal and reverse casting using a fixture

[0096] (6.1) Place the diamond dressing disc substrate after cleaning and degreasing in step 3 on a rotating coating table, and uniformly coat the brazing filler metal prepared in step 4 onto the substrate. The thickness of the coated brazing filler metal is 28% of the average height of the diamond abrasive grains.

[0097] (6.2) The substrate obtained in step 6.1 is flipped onto the ceramic mold on which diamonds were implanted in step 5.2. This allows each diamond to be held by brazing filler metal, reducing the chance of diamonds falling off. It is then clamped with a clamp to form a structure with the upper layer being the trimming disc stainless steel substrate, the middle layer being diamonds, and the bottom layer being the ceramic mold.

[0098] (6.3) Use a clamp to clamp the blank obtained in step 6.2, ensuring that the exposed diamond height between the substrate and the ceramic mold is controlled at 0.2mm and that the apex is flush, thus completing the reverse casting process. Apex alignment is adopted.

[0099] (7) Processing using a vacuum brazing furnace

[0100] (7.1) A vacuum furnace is used to evacuate the system to a vacuum level of 10. -3 Pa, heat the preliminary blank obtained in step 6 to 1020℃ and hold for 5 minutes.

[0101] (7.2) Introduce nitrogen containing ammonia to perform surface treatment on the weldment and cool it in the furnace. The ammonia ratio is controlled at 15%, and the nitrogen pressure is maintained at 10 Pa. Cool to room temperature in a nitrogen atmosphere and remove the weldment.

[0102] (8) Post-processing

[0103] After removing the clamps, the acrylic pressure-sensitive adhesive loses its adhesiveness at high temperatures, allowing the diamond dressing disc to naturally separate from the ceramic mold. The diamond dressing disc is then cleaned with acetone solution and rinsed with distilled water. After removal, it is dried in an oven to obtain the finished diamond dressing disc.

[0104] Example 2

[0105] The following differences exist compared to Example 1:

[0106] Step 1: The raw material components include alumina, zirconium oxide, magnesium oxide, calcium oxide, and thermally conductive additives, with a mass ratio of 85%:4%:3%; 3%:4%; the pattern design is carried out on the mold surface using screen printing technology;

[0107] Step 2: Use a diamond sorting machine to screen diamonds with a mesh size of 65.

[0108] Step 4: The copper-based brazing filler metal contains Cu, Al, Ni, Cr, and Ti in a mass ratio of 60%:5%:25%:3%:7%; Mixture C is mixed with acrylic pressure-sensitive adhesive at a weight ratio of 1:2.5 and stirred for 20 minutes using a magnetic stirrer at 400 rpm.

[0109] In step five: the tilt angle of the diamond is controlled to be 50°.

[0110] Step 7: Evacuate the vacuum furnace to a vacuum state, with a vacuum level of 10. -4 Pa, heat to 1040℃ and hold for 4 minutes; introduce nitrogen gas containing ammonia to treat the surface of the weldment and cool with the furnace, keeping the nitrogen pressure at 10 Pa, with the ammonia ratio controlled at 20%.

[0111] Example 3

[0112] The following differences exist compared to Example 1:

[0113] Step 1: The raw material components include alumina, zirconium oxide, magnesium oxide, calcium oxide, and thermally conductive additives, with a mass ratio of 90%:2%:3%; 2%:3%; and the pattern design is carried out on the mold surface using screen printing technology.

[0114] Step 2: Use a diamond sorting machine to screen diamonds with a mesh size of 70.

[0115] Step 4: The copper-based brazing filler metal consists of Cu, Al, Ni, Cr, and Ti in a mass ratio of 70%:8%:18%:2%:2%; Mixture C is mixed with acrylate pressure-sensitive adhesive at a weight ratio of 1:3.5 and stirred for 40 minutes at 600 rpm using a magnetic stirrer.

[0116] In step five: the tilt angle of the diamond is controlled to be 60°;

[0117] Step 7: Evacuate the vacuum furnace to a vacuum state, with a vacuum level of 10. -5 Pa, heat to 1050℃ and hold for 3 minutes; introduce nitrogen gas containing ammonia to treat the surface of the weldment and cool with the furnace, maintaining the nitrogen pressure at 10 Pa, with the ammonia ratio controlled at 25%.

[0118] Example 4

[0119] The difference from Example 1 is that diamond selection is not performed, ceramic molds are not used for orderly diamond arrangement, and reverse casting process is not used to control the exposed diamond height. This Example 4 is an existing method.

[0120] Figure 3The performance table for diamond dressing discs is provided. Top alignment refers to the diamond top alignment tolerance. As can be seen from Table 3, the lifespan of the polishing pads in Examples 1, 2, and 3 is longer than that in the existing Example 4.

[0121] To further illustrate the effects of the present invention, such as Figure 4 As shown in the table, the lifespan of the polishing pads for the examples and control examples is as follows. A grinding test machine was used to perform grinding tests on the diamond dressing disc. The dressing effect of the samples from the examples and control examples on the polishing pads was tested, and the lifespan of the polishing pads was observed. The smaller the error at the diamond tip, the more uniform the dressing of the polishing pad, and the longer the service life of the polishing pad. Figure 4 As shown in the table, the polishing pads in Examples 1, 2, and 3 have a longer service life than the existing Example 4.

[0122] Obviously, the diamond dressing disc prepared by this invention has improved performance, extended the service life of the polishing pad, and reduced manufacturing costs compared with dressing discs manufactured by traditional brazing processes.

[0123] A brazed diamond dressing disc is characterized by comprising a diamond, a substrate, and a brazing filler metal, wherein the diamond is brazed onto the substrate by the brazing filler metal, and the brazed diamond dressing disc is manufactured using any of the above-mentioned brazed diamond dressing disc manufacturing methods.

[0124] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for manufacturing a brazed diamond dressing disc, characterized in that, The process includes the following steps: ceramic mold making and preparation, diamond selection, cleaning of the stainless steel diamond dressing disc substrate, mold, and diamond, brazing filler metal making, adhesive coating and diamond embedding, brazing filler metal coating and fixture application, vacuum brazing furnace processing, and post-processing. (1) Steps for making and preparing ceramic molds: Make a new mold or prepare an existing mold according to the arrangement of diamond points and the spacing of diamonds; (2) Diamond selection steps: Use a diamond sorting machine to screen, classify and mark 55-65 mesh diamonds, and select diamonds with a height between 0.25-0.30mm, and diamonds with a single crystal morphology and (111) crystal faces for subsequent processing. (3) Cleaning steps for the stainless steel diamond dressing disc substrate, mold, and diamond: (3.1) The required stainless steel diamond dressing disc substrate is prepared by machining and the stainless steel diamond dressing disc substrate is cleaned by degreasing and rust removal. (3.2) Acid and alkali purification treatment was performed on the ceramic mold and the diamond with (111) crystal facets; (4) Steps for making brazing filler metal: (4.1) A copper-based brazing filler metal is prepared by mixing Cu, Al, Ni, Cr and Ti in a mass ratio of 60%-75%:5%-10%:10%-20%:2%-4%:1%-10%, and the mixture is uniformly mixed to obtain mixture C; (4.2) Mixture C and adhesive are mixed in a weight ratio of 1:1-4 to prepare a brazing filler slurry; (5) Adhesive coating and diamond embedding steps: (5.1) Apply acrylate pressure-sensitive adhesive to the ceramic mold in step 1 as an adhesive layer for diamond; (5.2) Using a point drilling machine, diamonds with (111) crystal faces after cleaning in step 3 are orderly planted on a ceramic mold according to the design pattern and point spacing. At the same time, the diamond tips are controlled to face downwards, the diamond tilt angle is between 50° and 60°, and the diamond cutting edges are oriented and consistent. (6) Coating of brazing filler metal and application of fixtures (6.1) The brazing filler metal obtained in step 4 is uniformly coated onto the stainless steel diamond dressing disc substrate after degreasing, derusting and cleaning in step 3. The coating height range is between 25% and 30% of the average height of the diamond abrasive grains, that is, the coating height is controlled between 0.05 and 0.1 mm. (6.2) The stainless steel diamond dressing disc substrate obtained in step 6.1 is flipped onto the ceramic mold on which diamonds were implanted in step 5.2, forming a sequence in which the upper layer is the stainless steel diamond dressing disc substrate, the middle layer is diamonds, and the bottom layer is the ceramic mold. (6.3) Use a clamp to clamp the blank obtained in step 6.2 to ensure that the exposed height of the diamond between the stainless steel diamond dressing disc substrate and the ceramic mold is controlled at 0.2mm and the apex is flush, thus completing the reverse casting process. (7) Processing steps using a vacuum brazing furnace A vacuum furnace was used to evacuate the system to a vacuum level of 10. -3 Pa~10 -6 Pa, the preliminary blank obtained in step 6 is heated to a brazing temperature of 1000℃-1200℃ and brazed for 3-5 minutes. Then, nitrogen containing 10%-30% ammonia is introduced to treat the surface of the weldment and it is cooled with the furnace. The pressure range of nitrogen is 10Pa~50Pa. (8) Post-processing steps: Post-processing is performed to obtain the finished diamond dressing disc. The diamond dressing disc includes diamond, stainless steel diamond dressing disc substrate, and brazing filler metal. The diamond is welded to the stainless steel diamond dressing disc substrate by brazing filler metal.

2. The method for manufacturing a brazed diamond dressing disc according to claim 1, characterized in that: If the mold is to be remade during the mold making or preparation process, the following steps are included: (1.1) Alumina, zirconium oxide, magnesium oxide and calcium oxide are used as raw materials, with a mass ratio range of 80%-95%: 2%-5%: 1%-4%: 2%-5%, and are mixed evenly to obtain mixture A; (1.2) Mixture A with a thermally conductive additive composed of carbon nanotubes and graphene sheets in a certain ratio, with the addition mass range controlled between 2% and 5%, to obtain mixture B; (1.3) The mixture B is introduced into the mold for molding. The pressure range is controlled within 100-200MPa. Then, the pattern is designed on the surface of the mold. The pattern involves the arrangement of diamond points and the spacing of diamonds. Depending on the different process requirements and different polishing pads, the spacing of diamonds is controlled between 1 and 2 mm. (1.4) Finally, inject an inert atmosphere such as nitrogen or rare gas, and sinter at 1400-1800℃ to obtain an alumina ceramic mold.

3. The method for manufacturing a brazed diamond dressing disc according to claim 1 or 2, characterized in that: (6.1) In the steps of coating the brazing filler metal and using the fixture, the brazing filler metal is evenly coated on the stainless steel diamond dressing disc substrate, and the coating height is controlled between 0.05-0.1mm.

4. The method for manufacturing a brazed diamond dressing disc according to claim 3, characterized in that: (1) In the process of making or preparing ceramic molds, the raw material components include alumina, zirconium oxide, magnesium oxide, calcium oxide and thermally conductive additives, with a mass ratio of 90%:3%:2%; 2%：3%； (2) In the diamond selection process, diamonds with a mesh size of 60 are screened; (4) In the process of making the brazing filler metal, the raw materials of the copper-based brazing filler metal are Cu, Al, Ni, Cr and Ti, with a mass ratio of 64%:6%:20%:2%:8%, which are mixed evenly to obtain mixture C; mixture C is mixed with acrylic pressure-sensitive adhesive in a weight ratio of 1:3 to prepare brazing filler metal solution. (5) In the steps of coating the adhesive and planting the diamond, the tilt angle of the diamond is controlled to be 55°. (6) In the steps of coating the brazing filler metal and using the fixture, the thickness of the coated brazing filler metal is 28% of the average height of the diamond abrasive grains, ensuring that the exposed height of the diamond between the stainless steel diamond dressing disc substrate and the ceramic mold is controlled at 0.2 mm. (7) In the vacuum brazing furnace processing step, a vacuum furnace is used to evacuate to a vacuum state with a vacuum degree of 10. -3 Pa, the preliminary blank obtained in step 6 is heated to 1020℃ and held for 5 minutes. Nitrogen gas containing ammonia is introduced to perform surface treatment on the weldment and then cooled with the furnace. The ammonia ratio is controlled at 15%, and the nitrogen pressure is maintained at 10Pa.

5. The method for manufacturing a brazed diamond dressing disc according to claim 3, characterized in that: (1) In the process of making or preparing ceramic molds, the raw material components include alumina, zirconium oxide, magnesium oxide, calcium oxide and thermally conductive additives, with a mass ratio of 85%:4%:3%; 3%：4%； (2) In the diamond selection process, diamonds with a mesh size of 65 are screened. (4) In the process of making the brazing filler metal, the raw materials for the copper-based brazing filler metal are Cu, Al, Ni, Cr and Ti, with a mass ratio of 60%:5%:25%:3%:7%, which are mixed evenly to obtain mixture C; mixture C is mixed with acrylic pressure-sensitive adhesive at a weight ratio of 1:2.5 to prepare brazing filler metal solution. (5) In the steps of coating the adhesive and planting the diamond, the tilt angle of the diamond is controlled to be 50°. (6) In the steps of coating the brazing filler metal and using the fixture, the thickness of the coated brazing filler metal is 28% of the average height of the diamond abrasive grains, ensuring that the exposed height of the diamond between the stainless steel diamond dressing disc substrate and the ceramic mold is controlled at 0.2 mm. (7) In the vacuum brazing furnace processing step, a vacuum furnace is used to evacuate to a vacuum state with a vacuum degree of 10. -4 Pa, the preliminary blank obtained in heating step 6 is heated to 1040℃ and held for 4 minutes. Nitrogen gas containing ammonia is introduced to perform surface treatment on the weldment and then cooled with the furnace. The ammonia ratio is controlled at 20%, and the nitrogen pressure is maintained at 10Pa.

6. The method for manufacturing a brazed diamond dressing disc according to claim 3, characterized in that: (1) In the process of making or preparing ceramic molds, the raw material components include alumina, zirconium oxide, magnesium oxide, calcium oxide and thermally conductive additives, with a mass ratio of 90%:2%:3%; 2%：3%； (2) In the diamond selection process, diamonds with a mesh size of 70 are screened; (4) In the process of making the brazing filler metal, the raw materials of the copper-based brazing filler metal are Cu, Al, Ni, Cr and Ti, with a mass ratio of 70%:8%:18%:2%:2%, which are mixed evenly to obtain mixture C; mixture C is mixed with acrylic pressure-sensitive adhesive at a weight ratio of 1:3.5 to prepare brazing filler metal solution. (5) In the steps of coating the adhesive and planting the diamond, the tilt angle of the diamond is controlled to be 60°. (6) In the steps of coating the brazing filler metal and using the fixture, the thickness of the coated brazing filler metal is 28% of the average height of the diamond abrasive grains, ensuring that the exposed height of the diamond between the stainless steel diamond dressing disc substrate and the ceramic mold is controlled at 0.2 mm. (7) In the vacuum brazing furnace processing step, a vacuum furnace is used to evacuate to a vacuum state with a vacuum degree of 10. -5 Pa, the preliminary blank obtained in heating step 6 is heated to 1050℃ and held for 3 minutes. Nitrogen gas containing ammonia is introduced to perform surface treatment on the weldment and then cooled with the furnace. The ammonia ratio is controlled at 25%, and the nitrogen pressure is maintained at 10Pa.

7. The method for manufacturing a brazed diamond dressing disc according to claim 1, characterized in that: The post-processing steps are as follows: remove the clamps, the adhesive loses its adhesiveness at high temperature, and the diamond dressing disc naturally separates from the ceramic mold; clean the diamond dressing disc with acetone solution, and then rinse it with distilled water; after taking it out, dry it in an oven to obtain the finished diamond dressing disc.

8. A brazed diamond dressing disc, characterized in that: The device comprises diamond, a stainless steel diamond dressing disc substrate, and brazing filler metal. The diamond is brazed onto the stainless steel diamond dressing disc substrate by brazing filler metal. The brazed diamond dressing disc is manufactured by the brazed diamond dressing disc manufacturing method according to any one of claims 1-7.

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