A casting mold, method, and polishing pad for forming an ordered abrasive polishing pad

Abstract

The application relates to a casting mold, a method and a polishing pad for forming an ordered abrasive polishing pad. Compared with the prior art, the grinding columnar body of the application extends from the bottom plate, the plurality of grinding columnar bodies are orderly distributed on the bottom plate, the grinding columnar body and the bottom plate are made of grinding materials such as silicon dioxide, cerium dioxide or aluminum oxide, the bottom plate is placed in a mold cavity, the bayonet element is clamped to the bottom plate by a moving part to fix the position of the bottom plate, the mold is vacuumized through a vacuum exhaust hole, polyurethane prepolymer is poured through a pouring inlet of the mold cavity, a negative pressure is formed, the polyurethane prepolymer fills the gap between the grinding columnar bodies on the bottom plate, the polyurethane prepolymer is solidified to form a filling body which is flush with the grinding columnar bodies on the bottom plate, the filling body is in close contact with the grinding columnar body, the filling body is prevented from being separated from the grinding columnar body during polishing to cause the fracture of the grinding columnar body, and the polishing pad with the stable and orderly fixed distribution of the grinding columnar body is formed.

Description

Technical Field

[0001] This invention relates to the field of semiconductor product polishing technology, and in particular to a casting mold, method, and polishing pad for forming an ordered abrasive polishing pad. Background Technology

[0002] Chemical mechanical polishing (CMP) is a global planarization process that combines chemical etching and mechanical polishing, and is widely used in the semiconductor manufacturing industry. This technology achieves nanoscale to atomic-level planarization of wafer surfaces by synergistically softening the material surface with mechanically removing reactants, effectively addressing the planarization requirements of multilayer metal interconnects and copper damascene processes. CMP equipment includes key components such as polishing and cleaning units, and its main consumables include polishing slurry, polishing pads, and carrier films.

[0003] Currently, Chinese invention patent document CN103561907A also discloses a polishing pad for polishing substrates, including a homogeneous body and multiple discrete protrusions formed on the polishing surface of the homogeneous body and covalently bonded to the polishing surface. The homogeneous body and the discrete protrusions are made of materials with different hardness. Both the homogeneous body and the discrete protrusions are polyurethane materials that can be covalently bonded. The polishing pad formed is still a traditional polyurethane material polishing pad.

[0004] Polyurethane polishing pads need to work together with the abrasive particles in the polishing slurry to physically remove wafer materials. The abrasive particles are irregularly distributed in shape and direction as they flow with the polishing liquid on the polishing pad, resulting in poor chemical stability of the polishing pad during polishing and poor polishing effect of the polishing pad. Summary of the Invention

[0005] The purpose of this invention is to overcome the defects of the prior art by providing a casting mold, method and polishing pad for forming ordered abrasive polishing pads.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] According to the present invention, a casting mold for forming an ordered abrasive polishing pad includes a base plate and a plurality of grinding columns; the grinding columns extend from the base plate in a direction away from the base plate, so that the plurality of grinding columns are orderly distributed and fixed on the base plate; the grinding columns and the base plate are made of one or more of silicon dioxide, cerium dioxide, or aluminum oxide; the casting mold includes a mold cavity and a mold cover plate; the mold cavity has an inlet for inserting the base plate on which the grinding columns are fixed, the base plate is placed flat in the mold cavity, and a plurality of support members for supporting the base plate are distributed around the side wall of the base plate in the mold cavity, the support members including a blocking part and a moving part; the moving part moves through the side wall of the mold cavity; the blocking part is fixed to one end of the moving part, and the blocking part is used for... The moving part is supported on the outside of the mold cavity; a latching member is formed at the end of the moving part away from the blocking part for clamping the base plate, and the size of the latching member is adapted to the thickness of the base plate to fix the position of the base plate; the mold cover plate is used to block the inlet of the mold cavity; the mold cover plate is provided with a vacuum extraction hole communicating with the mold cavity, and the side wall of the mold cavity is provided with a pouring port for pouring polyurethane prepolymer, so as to fill the gap between the grinding columns on the base plate by pouring polyurethane prepolymer under negative pressure. The polyurethane prepolymer solidifies to form a polyurethane filler that is flush with the grinding columns on the base plate, so that the polyurethane filler is in close contact with the grinding columns, preventing the polyurethane filler from falling out of the grinding columns during polishing and causing the grinding columns to break, forming a polishing pad with stable and orderly fixed distribution of grinding columns.

[0008] Compared with the prior art, the grinding columnar body of the present invention extends from the base plate, and multiple grinding columnar bodies can be orderly distributed and fixed on the base plate. The grinding columnar bodies and the base plate are made of grinding materials such as silicon dioxide, cerium dioxide, or alumina. By placing the base plate with the grinding columnar bodies into the mold cavity, the movement of the moving part drives the locking mechanism to lock the base plate, fixing its position. The blocking part can support the outside of the mold cavity to prevent the support member from falling into the mold cavity. The mold cavity is covered by the mold cover plate, and the mold is vented through the vacuum extraction hole. A vacuum is created, and polyurethane prepolymer is poured into the mold cavity through the injection port, forming a negative pressure to fill the gaps between the grinding columns on the base plate. The polyurethane prepolymer solidifies to form a polyurethane filler flush with the grinding columns on the base plate. This filler ensures full contact with the base plate and penetrates between the grinding columns, preventing them from detaching during polishing and causing breakage. This results in a stable and orderly polishing pad with fixed grinding columns. By fixing the position of the base plate, the polishing pad maintains its position during the liquid polyurethane pouring and curing process, improving the quality of the polishing pad and reducing the difficulty of post-processing and product scrap rate. Furthermore, this polishing pad transforms the traditional flow combination of fluid abrasive and the polishing pad body into a fixed combination of abrasive columns and polyurethane filler. It can even achieve slurry-free polishing pads. The flush abrasive columns and polyurethane filler work together to polish semiconductor workpieces, providing a stable contact interface between the polishing pad and the surface of the wafer or other polished product. This effectively reduces process fluctuations caused by the flow variability of traditional polishing pads, improves the chemical stability of the polishing pad during polishing, enables more precise control of material removal rate and higher wafer surface flatness, achieves higher abrasive removal rates and lower surface roughness, improves the polishing effect of the polishing pad on the polished product, and enhances the quality of the polished product. It is particularly suitable for advanced chip manufacturing nodes with extremely high flatness requirements, and it reduces abrasive waste and polishing pad body wear.

[0009] Preferably, a fixed sleeve is formed around the blocking part outside the mold cavity. The fixed sleeve has a blocking movement area and an internal thread area. The blocking movement area is used to move in accordance with the blocking part. The internal thread area is located on the side of the blocking movement area away from the mold cavity. The fixed sleeve is provided with a threaded post that is threadedly connected to the internal thread area, so that the threaded post can rotate to push the blocking part to move, thereby driving the bayonet to clamp the base plate, so as to improve the stability of the bayonet when clamping the base plate.

[0010] Preferably, a first elastic buffer is provided between the blocking part and the threaded post, so that the multiple clamping parts can flexibly clamp the base plate using the elastic force of the first elastic buffer, preventing the multiple clamping parts from rigidly squeezing the base plate and causing the base plate to break.

[0011] Preferably, a second elastic buffer is formed between the blocking part and the outside of the mold cavity, and the second elastic buffer is arranged around the blocking part. When the latch clamps the bottom plate, both the first elastic buffer and the second elastic buffer are in a compressed state, so that when the latch is detached from the bottom plate, the second elastic buffer uses its own elastic restoring force to push the blocking part to drive the latch to abut against the inner wall of the mold cavity.

[0012] Preferably, the second elastic buffer is configured as a spring and there are multiple second elastic buffers arranged around the blocking portion, and hooks are formed at both ends of the second elastic buffers, and hooks that are connected to the hooks are formed on the outside of the mold cavity and on the blocking portion.

[0013] Preferably, multiple support members corresponding to a base plate are set as a group. The grouped support members can be arranged in multiple groups at intervals along the depth direction of the mold cavity. The second elastic buffer member makes it easy to place multiple groups of the base plate when the locking member abuts against the inner side wall of the mold cavity. The locking member keeps the distance between the base plates unchanged.

[0014] According to the present invention, a casting method for forming an ordered abrasive polishing pad is provided, using any of the casting molds described above for forming an ordered abrasive polishing pad, comprising: the polyurethane filler being cast and cured between grinding columnar bodies on a base plate under a preset negative pressure condition; wherein the preset negative pressure condition is to maintain a constant negative pressure during the casting process, and the negative pressure value is -0.5MPa to -1.5MPa.

[0015] According to the present invention, a polishing pad is formed by casting an ordered abrasive polishing pad using any of the above-described casting molds for forming ordered abrasive polishing pads.

[0016] Preferably, the grinding column array is arranged in an orderly manner, the array shape of the grinding column array is a regular polygon array, and the array distribution density and / or scratch density of the grinding column array are positively correlated with the removal rate of the polished product, so as to select the array distribution shape of the grinding column array.

[0017] Preferably, the array distribution shape of the grinding columnar bodies is a square array corresponding to two scratches, an equilateral triangle array corresponding to three scratches, or a regular hexagonal array corresponding to four scratches.

[0018] And / or, the grinding plane of the grinding column is circular, square, or triangular. Attached Figure Description

[0019] Figure 1 This is a top view of the casting mold cover of the present invention;

[0020] Figure 2 This is a left view of the casting mold cover of the present invention;

[0021] Figure 3 This is a front view of the casting mold cover of the present invention;

[0022] Figure 4 This is a front view of the casting mold of the present invention;

[0023] Figure 5 This is a top view of the casting mold of the present invention;

[0024] Figure 6 This is a schematic diagram of the casting mold of the present invention with a first elastic buffer member;

[0025] Figure 7 This is a schematic diagram of the casting mold of the present invention with a second elastic buffer;

[0026] Figure 8 This is a schematic diagram of the bonded abrasive polishing pad with an ordered square array according to the present invention;

[0027] Figure 9 This is a schematic diagram of the bonded abrasive polishing pad with an ordered triangular array according to the present invention;

[0028] Figure 10 This is a schematic diagram of the bonded abrasive polishing pad with an ordered hexagonal array according to the present invention;

[0029] Figure 11 This is a schematic diagram of the polishing pad of the present invention in use;

[0030] Figure 12 This is a schematic diagram showing the three scratches generated by the triangular array of the polishing pad of the present invention during use;

[0031] Figure 13 This is a schematic diagram showing two scratches generated by the square array of the polishing pad of the present invention during use;

[0032] Figure 14 This is a schematic diagram showing the four scratches generated by the hexagonal array of the polishing pad of the present invention during use.

[0033] Reference numerals: 1. Mold cover plate; 2. Vacuum extraction hole; 3. Handle; 4. Mold cavity; 5. Support component; 501. Moving part; 502. Blocking part; 6. Sprue; 7. Support platform; 701. Support bottom surface; 702. Restricting ring surface; 8. Fixing sleeve; 9. Threaded column; 10. Bayonet; 11. Base plate; 12. Polyurethane filler; 13. Grinding column; 14. First elastic buffer; 15. Second elastic buffer. Detailed Implementation

[0034] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0035] This specification provides an embodiment of a casting mold for forming an ordered abrasive polishing pad, such as... Figure 8 and Figure 11 As shown, the ordered abrasive polishing pad includes a base plate 11 and a plurality of grinding columns 13; the grinding columns 13 extend from the base plate 11 in a direction away from the base plate 11, so that the plurality of grinding columns 13 are orderly distributed and fixed on the base plate 11. The grinding columns 13 and the base plate 11 are both made of one or more of silicon dioxide, cerium dioxide, or aluminum oxide. Figure 1 , Figure 4 as well as Figure 5 As shown, the casting mold includes a mold cavity 4 and a mold cover plate 1; the mold cavity 4 has an inlet for placing a base plate 11 on which a grinding column 13 is fixed, the base plate 11 is placed flat inside the mold cavity 4, and multiple support members 5 for supporting the base plate 11 are distributed around the side wall of the base plate 11 inside the mold cavity 4.

[0036] like Figure 4 and Figure 6 As shown, the support member 5 includes a blocking part 502 and a moving part 501; the moving part 501 moves through the side wall of the mold cavity 4; the blocking part 502 is fixed at one end of the moving part 501 and is used to support the outside of the mold cavity 4; a latching member 10 for clamping the base plate 11 is formed at the end of the moving part 501 away from the blocking part 502, and the size of the latching member 10 is adapted to the thickness of the base plate 11 to fix the position of the base plate 11; the size of the latching member 10 can also be the total thickness of the base plate 11 and the grinding column 13, so that the inner upper surface of the latching member 10 contacts the upper part of the grinding column 13 and the inner lower surface contacts the bottom surface of the base plate 11.

[0037] The mold cover plate 1 is used to seal the inlet of the mold cavity 4; the mold cover plate 1 has a vacuum extraction hole 2 that connects to the mold cavity 4, serving as a vacuum interface; and the side wall of the mold cavity 4 has a pouring inlet 6 for pouring polyurethane prepolymer, so that the polyurethane prepolymer is poured under negative pressure to fill the gaps between the grinding columns 13 on the base plate 11. The polyurethane prepolymer solidifies to form a polyurethane filler 12 that is flush with the grinding columns 13 on the base plate 11, so that the polyurethane filler 12 is in close contact with the grinding columns 13, preventing the polyurethane filler 12 from falling out of the grinding columns 13 during polishing and causing the grinding columns 13 to break, thus forming a polishing pad with a stable and orderly fixed distribution of the grinding columns 13. For example, the support member 5 is set to 3 according to each base plate 11.

[0038] In one embodiment, a fixed sleeve 8 is formed around the blocking part 502 outside the mold cavity 4. The fixed sleeve 8 has a blocking movement area and an internal thread area. The blocking movement area is adapted to move with the blocking part 502. The internal thread area is located on the side of the blocking movement area away from the mold cavity 4. The fixed sleeve 8 has a threaded post 9 that is threadedly connected to the internal thread area, so that the rotation of the threaded post 9 pushes the blocking part 502 to move, causing the bayonet 10 to clamp the base plate 11, thereby improving the stability of the bayonet 10 when clamping the base plate 11. Besides the combination of threads and threaded sleeves, pneumatic pressure or directly pullable pins can also be used. In particular, the number of openings in the bayonet 10 can be varied according to actual needs.

[0039] In one embodiment, such as Figure 6 As shown, a first elastic buffer 14 is provided between the blocking part 502 and the threaded post 9, so that the multiple clamping parts 10 can flexibly clamp the base plate 11 using the elastic force of the first elastic buffer 14, preventing the multiple clamping parts 10 from rigidly pressing the base plate 11 and causing the base plate 11 to break. The first elastic buffer 14 can prevent rigid contact with the base plate 11 and prevent the base plate 11 from breaking. The first elastic buffer 14 is, for example, a spring, elastic rubber, etc.

[0040] In one embodiment, such as Figure 7 As shown, a second elastic buffer 15 is formed between the blocking part 502 and the outside of the mold cavity 4, and the second elastic buffer 15 is arranged around the blocking part 502. When the latching member 10 clamps the bottom plate 11, both the first elastic buffer 14 and the second elastic buffer 15 are in a compressed state. When the latching member 10 is released from the bottom plate 11, the second elastic buffer 15 uses its own elastic restoring force to push the blocking part 502 and drive the latching member 10 to abut against the inner wall of the mold cavity 4.

[0041] When the clamping member 10 moves in the direction of disengaging from the base plate 11, the elastic compression restoring force of the second elastic buffer member 15 is greater than or equal to the elastic compression restoring force of the first elastic buffer member 14, so that the clamping member 10 can abut against the inner wall of the mold cavity 4; when the clamping member 10 moves in the direction of clamping the base plate 11, the elastic compression restoring force of the second elastic buffer member 15 is equal to the elastic compression restoring force of the first elastic buffer member 14, so that the clamping member 10 can fix and clamp the base plate 11.

[0042] When the second elastic buffer 15 is in a compressed state using its own elastic restoring force, the latch 10 abuts against the inner wall of the mold cavity 4 using its own elastic restoring force, facilitating the placement of the base plate 11. The second elastic buffer 15 is, for example, a spring, and four or more are provided around the blocking part 502.

[0043] In one embodiment, the second elastic buffer 15 is configured as a spring and there are multiple second elastic buffers 15 distributed around the blocking part 502, and hooks are formed at both ends of the second elastic buffer 15, and hooks that are connected to the hooks are formed on the outside of the mold cavity 4 and on the blocking part 502.

[0044] In one embodiment, the second elastic buffer 15 is configured as an elastic sleeve, and the elastic sleeve is sleeved on the blocking part 502. The elastic sleeve can be a spring or an elastic bellows.

[0045] In one embodiment, the second elastic buffer 15 is a spring or elastic rubber, and the first elastic buffer is a spring.

[0046] In one embodiment, the planes on which the plurality of second elastic buffer members 15 support members are located are parallel to the bottom plane of the mold cavity 4, so that the bottom plate 11 of the product to be poured is placed flat inside the mold cavity 4.

[0047] In one embodiment, multiple support members 5 corresponding to a base plate 11 are configured as a group. The grouped support members 5 can be arranged in multiple groups at intervals along the depth direction of the mold cavity 4. The second elastic buffer member 15 facilitates the placement of multiple groups of base plates 11 when the locking member 10 abuts against the inner wall of the mold cavity 4, and the locking member 10 maintains a constant distance between the base plates 11. That is, multiple support members 5 are configured along the depth direction of the mold cavity 4 so that the base plates 11 are arranged at intervals along the depth direction of the mold cavity 4. The moving part 501 is, for example, a cuboid columnar pin, and the blocking part 502 is, for example, a plate-like structure. When placing the base plate 11, the support member 5 that obstructs the placement of the base plate 11 can be removed, and the support member 5 that supports the base plate 11 can be pushed in. Three or more groups of support members 5 are configured along the depth direction of the mold cavity 4.

[0048] In one embodiment, multiple gating inlets 6 are provided along the depth direction of the mold cavity 4, and the gating inlets 6 and the support members 5 are staggered. The number of gating inlets 6 can be specifically designed according to actual needs, rather than a fixed number, for example, 5. The flow rate of each gating pipe is 0.1 kg / min to 10 kg / min.

[0049] In one embodiment, such as Figure 2 , Figure 3 as well as Figure 4 As shown, a pair of handles 3 are provided on the mold cover plate 1. A support platform 7 is formed around the inlet of the mold cavity 4 to cooperate with and cover the mold cover plate 1. The support platform 7 includes a supporting bottom surface 701 and a restricting ring surface 702 extending vertically from the supporting bottom surface 701. The supporting bottom surface 701 contacts the surface of the mold cover plate 1 facing the mold cavity 4, and the restricting ring surface 702 contacts the side periphery of the mold cover plate 1. The outer diameter of the mold cover plate 1 and the inner diameter of the restricting ring surface 702 are within a tolerance of 0.1 ± 0.02 mm. A sealing strip and a sealing ring are provided on the support platform 7 to cooperate with the mold cover plate 1 to prevent air leakage.

[0050] The grinding column 13 can be as small as a micro-nano structure. When it is compounded with polyurethane, the micro-nano structure effect on the surface of the micro-nano structure prevents the polyurethane from fully penetrating into the micro-nano structure, making the micro-nano structure prone to breakage during the grinding process. The casting mold of this invention allows the polyurethane and the micro-nano structure to be fully mixed.

[0051] This invention utilizes support member 5 to place base plate 11 layer by layer into the mold, and fixes base plate 11 with clamping member 10. Then, mold cover plate 1 is placed on top, and self-sealing is achieved by the weight of mold cover plate 1 and sealing ring. Subsequently, with vacuum activated, polyurethane is poured into the mold at a specific flow rate through pouring port 6 to completely expel air from the gaps between grinding column bodies 13, achieving complete bonding of polyurethane with base plate 11 containing grinding column bodies 13.

[0052] This mold design allows for the single-pour preparation of a molded cake containing multiple micro-base plates 11. The position of the base plates 11 is fixed by the locking mechanism 10, enabling precise control of their placement within the mold and providing space for subsequent cutting of the cake into polishing pads. This mold design utilizes a negative pressure pouring method to prevent gaps between the grinding columns 13 on the base plates 11, which would otherwise prevent the polyurethane from fully mixing with the base plates 11 containing the grinding columns 13.

[0053] This specification also discloses a casting method for forming an ordered abrasive polishing pad, using any of the casting molds for forming an ordered abrasive polishing pad described in the above embodiments, comprising: a polyurethane filler 12 being cast and cured between grinding columnar bodies 13 on a base plate 11 under a preset negative pressure condition; wherein, the preset negative pressure condition is to maintain a constant negative pressure during the casting process, with a negative pressure value of -0.5MPa to -1.5MPa, preferably -0.5MPa, and a negative pressure time of 1min to 30min, or, maintaining a constant negative pressure until vulcanization and curing are formed, so as to form a controllable, ordered, and array-structured bonded abrasive polishing pad.

[0054] This specification also provides a polishing pad, which is an ordered abrasive polishing pad formed by casting using any of the casting molds for forming ordered abrasive polishing pads described in the above embodiments, such as... Figure 8 and Figure 11 As shown, the assembly includes a base plate 11, a polyurethane filler 12, and multiple grinding columns 13. The grinding columns 13 extend from the base plate 11 in a direction away from the base plate, allowing the multiple grinding columns 13 to be orderly fixed on the base plate 11. The polyurethane filler 12 is formed on the base plate 11 by casting polyurethane prepolymer under negative pressure, and the grinding columns 13 are flush with the polyurethane filler 12. For example, the multiple grinding columns 13 are arranged in concentric circles or spirals.

[0055] In one embodiment, a plurality of grinding columnar bodies 13 are arranged in an orderly array. The array distribution shape of the grinding columnar bodies 13 is a regular polygonal array, and the array distribution density and / or scratch density of the grinding columnar bodies 13 are positively correlated with the removal rate of the polished product, so as to select the array distribution shape of the grinding columnar bodies 13. A regular polygonal array, such as an equilateral triangle, square, or regular hexagonal array.

[0056] In one embodiment, the array distribution shape of the grinding column 13 is a square array corresponding to two scratches, an equilateral triangle array corresponding to three scratches, or a regular hexagonal array corresponding to four scratches.

[0057] And / or, the grinding plane of the grinding column 13 is circular, square or triangular in shape.

[0058] This invention designs the abrasive array arrangement in ordered bonded abrasive polishing pads, and provides theoretical optimal values ​​and simulation results, offering different grinding removal rates and surface roughness for ordered bonded abrasive polishing pads, thus expanding their application range. The grinding columnar bodies 13 are cast in square, solid square, and regular hexagonal arrays using vacuum casting. After casting and vulcanization, they form ordered polishing pads with different arrays.

[0059] like Figure 8As shown, for a non-solid square array, the grinding pillar radius is r, and the size is 0.02-200 μm. The spacing between the grinding pillars is k, and the size of k is 0.02-4000 μm. The grinding pillars of the polishing pad are also arranged in a solid square array, with square grinding pillars having a side length of r and a spacing of k. The area of ​​the polishing pad is taken as a. 2 The region (the grinding column is a circle with radius r and spacing k).

[0060] like Figure 9 As shown, for a solid square array, i.e., an equilateral triangle array, the radius of the grinding pillars is r, and the size is 0.02-200 μm. The spacing between the grinding pillars is k, and the size of k is 0.02-4000 μm. The grinding pillars of the polishing pad are also arranged in a solid square array, with square grinding pillars having a side length of r and a spacing of k. The area of ​​the polishing pad is taken as a. 2 The region (the grinding column is a circle with radius r and spacing k).

[0061] like Figure 10 As shown, for the hexagonal array, the radius of the grinding pillars is r, and the size ranges from 0.02 to 200 μm. The spacing between the grinding pillars is k, and the size of k ranges from 0.02 to 4000 μm. The grinding pillars of the polishing pad are also arranged in a solid square array, with square grinding pillars having a side length of r and a spacing of k. The area of ​​the polishing pad is taken as a. 2 The region (the grinding column is a circle with radius r and spacing k).

[0062] In addition to the square and circle listed in this invention, the shape of the grinding column can also be a triangle or other polygons.

[0063] Because of the different arrays, the effective grinding column area and sliding trajectory per unit area are different, resulting in different removal rates and surface roughness.

[0064] like Figure 8 As shown, assuming the existing side length is a, the area S = a 2 A polishing pad contains grinding pillars of radius r arranged in a square array, with a distance of k between the pillars. The number of grinding pillars per unit area is: Then in an area of ​​a 2 The polishing pad contains the following number of grinding pillars: Combining Figure 11 As shown, if a pressure P is applied to the workpiece, then... Since the height of each grinding column is the same everywhere, the force on a single grinding column can be determined. Therefore, when the radius of the grinding column remains constant, increasing the value of the grinding column distance k means that the pressure borne by a single grinding column increases. Similarly, when the grinding column distance k remains constant, increasing the area of ​​a single grinding column will also increase the pressure borne by the grinding column.

[0065] like Figure 9 As shown, when the grinding column array is changed to a solid square array, the number of grinding columns per unit area is: Then in an area of ​​a 2 The polishing pad contains the following number of grinding pillars: Then we can know the force on a single grinding column. Compared to a hollow array, the force on a single grinding column in a solid array is less than that in a hollow array. However, the influence of the grinding column radius and spacing k on the force on a single grinding column remains unchanged.

[0066] like Figure 10 As shown, when the grinding column array is changed to a hexagonal array, the number of grinding columns per unit area is: Then in an area of ​​a 2 The polishing pad contains the following number of grinding pillars: Then we can know the force on a single grinding column. .

[0067] As discussed above, different arrays result in varying densities of grinding columns per unit area, leading to different forces on individual grinding columns under the same pressure. Since the grinding columns are the primary material for removing workpiece material, different arrays will inevitably result in different removal rates. Similarly, regarding the impact on surface roughness, existing knowledge indicates that larger grinding columns experience greater forces, resulting in higher surface roughness. Therefore, bonded abrasive polishing pads can be designed with appropriate arrays and grinding column sizes to meet specific grinding requirements.

[0068] In addition to the different forces on individual grinding columns, the sliding trajectories also differ depending on the array. Figure 12 As a solid square array, there will theoretically be 3 scratches. Figure 13 If it is a hollow square array, there will be only 2 scratches. Figure 14 If the array is a regular hexagon, there will be 4 scratches. Different scratch densities will also affect the removal rate and roughness. Figure 12 , Figure 13 as well as Figure 14 The dotted lines in the text represent scratches.

[0069] This invention combines triangular, square, and hexagonal arrays with ordered bonded abrasive polishing pads. Because the number of grinding columns per unit density varies under different array conditions, the removal rate will be different. Different array polishing pads can be selected according to the material, removal rate, and roughness of the grinding object.

[0070] In one embodiment, the grinding column 13 is made of one or more of silicon dioxide, cerium dioxide, or aluminum oxide. The base plate 11 can be made of the same material as the grinding column 13, and the two can together form a substrate.

[0071] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A casting mold for forming an ordered abrasive polishing pad, characterized in that, The ordered abrasive polishing pad includes a base plate and multiple grinding columns; the grinding columns extend from the base plate in a direction away from the base plate, so that the multiple grinding columns are orderly distributed and fixed on the base plate. The grinding columns and the base plate are made of one or more of silicon dioxide, cerium dioxide, or aluminum oxide. The casting mold includes a mold cavity and a mold cover plate; the mold cavity has an inlet for placing the base plate on which the grinding columns are fixed, the base plate is placed flat in the mold cavity, and multiple support members for supporting the base plate are distributed around the side wall of the base plate in the mold cavity. The support members include a blocking part and a moving part; the moving part moves through the side wall of the mold cavity; the blocking part is fixed at one end of the moving part and is used to support the outside of the mold cavity. The moving part has a latching member at one end away from the blocking part for clamping the base plate, and the size of the latching member is adapted to the thickness of the base plate to fix the position of the base plate; the mold cover plate is used to block the inlet of the mold cavity; the mold cover plate has a vacuum extraction hole communicating with the mold cavity, and the side wall of the mold cavity has a pouring inlet for pouring polyurethane prepolymer, so that the polyurethane prepolymer is poured under negative pressure to fill the gap between the grinding columns on the base plate. The polyurethane prepolymer solidifies to form a polyurethane filler that is flush with the grinding columns on the base plate, so that the polyurethane filler is in close contact with the grinding columns, preventing the polyurethane filler from falling out of the grinding columns during polishing and causing the grinding columns to break, forming a polishing pad with a stable and orderly fixed distribution of grinding columns.

2. The casting mold for forming an ordered abrasive polishing pad according to claim 1, characterized in that, A fixed sleeve is formed around the blocking part outside the mold cavity. A blocking movement area and an internal thread area are formed inside the fixed sleeve. The blocking movement area is used to adapt to the movement of the blocking part. The internal thread area is located on the side of the blocking movement area away from the mold cavity. The fixed sleeve is provided with a threaded post that is threaded to the internal thread area so that the threaded post can rotate to push the blocking part to move, thereby driving the bayonet to clamp the base plate, so as to improve the stability of the bayonet when clamping the base plate.

3. The casting mold for forming an ordered abrasive polishing pad according to claim 2, characterized in that, A first elastic buffer is provided between the blocking part and the threaded post, so that the multiple clamping parts can flexibly clamp the base plate using the elastic force of the first elastic buffer, preventing the multiple clamping parts from rigidly squeezing the base plate and causing the base plate to break.

4. The casting mold for forming an ordered abrasive polishing pad according to claim 3, characterized in that, A second elastic buffer is formed between the blocking part and the outside of the mold cavity, and the second elastic buffer is arranged around the blocking part. When the latch clamps the bottom plate, both the first elastic buffer and the second elastic buffer are in a compressed state. When the latch is detached from the bottom plate, the second elastic buffer uses its own elastic restoring force to push the blocking part and drive the latch to abut against the inner wall of the mold cavity.

5. The casting mold for forming an ordered abrasive polishing pad according to claim 4, characterized in that, The second elastic buffer is configured as a spring and there are multiple second elastic buffers arranged around the blocking part, and hooks are formed at both ends of the second elastic buffers, and hooks that are connected to the hooks are formed on the outside of the mold cavity and on the blocking part.

6. The casting mold for forming an ordered abrasive polishing pad according to claim 4, characterized in that, Multiple support members corresponding to a base plate are set as a group. The support members set as a group are arranged at intervals along the depth direction of the mold cavity. The second elastic buffer member makes it easy to place multiple sets of the base plate when the locking member abuts against the inner side wall of the mold cavity. The locking member keeps the distance between the base plates unchanged.

7. A casting method for forming an ordered abrasive polishing pad, characterized in that, The casting mold for forming an ordered abrasive polishing pad according to any one of claims 1 to 6 includes: the polyurethane filler being cast and cured between grinding columnar bodies on a base plate under a preset negative pressure condition; wherein the preset negative pressure condition is to maintain a constant negative pressure during the casting process, and the negative pressure value is -0.5MPa to -1.5MPa.

8. A polishing pad, characterized in that, The ordered abrasive polishing pad is formed by casting using the casting mold for forming an ordered abrasive polishing pad as described in any one of claims 1 to 6.

9. The polishing pad according to claim 8, characterized in that, The grinding column array is arranged in an orderly manner, and the array distribution shape of the grinding column array is a regular polygon array. The array distribution density and / or scratch density of the grinding column array are positively correlated with the removal rate of the polished product, so as to select the array distribution shape of the grinding column array.

10. The polishing pad according to claim 9, characterized in that, The array distribution shape of the grinding columnar bodies is a square array corresponding to two scratches, an equilateral triangle array corresponding to three scratches, or a regular hexagonal array corresponding to four scratches. And / or, the grinding plane of the grinding column is circular, square, or triangular.

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