A method of making a polishing pad

Abstract

The present disclosure relates to a method for manufacturing a polishing pad, comprising: providing a substrate layer, at least a part of a surface of the substrate layer being a foamed material; disposing a foaming guide structure on the substrate layer, the foaming guide structure having a plurality of guide channels; based on the foaming guide structure, foaming the foamed material along the guide channels; and removing the foaming guide structure to obtain the polishing pad, wherein a foamed structure of the foamed material forms a polishing layer of the polishing pad. The method for manufacturing the polishing pad can ensure that the size of the pores formed in the polishing layer of the polishing pad in the extending direction is uniform, and the cross-sectional area of the pores at each position in the extending direction is more consistent.

Description

Technical Field

[0001] This disclosure relates to the field of abrasive technology, and more particularly to a method for manufacturing an abrasive pad. Background Technology

[0002] In device fabrication processes, such as the fabrication of semiconductor structures, polishing pads are typically used to grind and polish the surface. Existing polishing pads are usually porous with uneven pore sizes. During long-term use, residues generated during the polishing process can easily accumulate in the larger pores of the pad, which can adversely affect subsequent polishing processes of the semiconductor structure. Summary of the Invention

[0003] The following is an overview of the subject matter described in detail in this disclosure. This overview is not intended to limit the scope of the claims.

[0004] This disclosure provides a method for manufacturing an abrasive pad, the method comprising:

[0005] A substrate layer is provided, wherein at least a portion of the surface of the substrate layer is a foamed material;

[0006] A foaming guide structure is provided on the substrate layer, and the foaming guide structure has multiple guide channels;

[0007] Based on the foaming guide structure, the foaming material is foamed so that the foaming material foams along each of the guide channels. The foaming guide structure is then removed to obtain the abrasive pad, wherein the foaming structure obtained by foaming the foaming material forms the abrasive layer of the abrasive pad.

[0008] According to some embodiments of this disclosure, the foamed guide structure includes at least one layer of mesh structure, and the mesh holes of the mesh structure constitute the guide channel.

[0009] According to some embodiments of this disclosure, the material of the mesh structure includes carbon fiber.

[0010] According to some embodiments of this disclosure, the guide channel is perpendicular to the surface of the substrate layer.

[0011] According to some embodiments of this disclosure, the size of the opening of the guide channel is 2μm-20μm.

[0012] According to some embodiments of this disclosure, after removing the foamed guiding structure, the method for manufacturing the abrasive pad further includes:

[0013] Grooves for accommodating abrasive slurry are formed on the surface of the foamed material after the foaming guide structure is removed.

[0014] According to some embodiments of this disclosure, removing the foaming guide structure includes:

[0015] The foaming material and the foaming guide structure located above the abrasive layer can be removed by mechanical grinding; or, the foaming material and the foaming guide structure located above the abrasive layer can be removed by chemical etching.

[0016] According to some embodiments of this disclosure, the foaming treatment of the foamed material based on the foaming guiding structure includes:

[0017] A foaming agent is injected into each of the guide channels, so that the foaming agent comes into contact with the foaming material through the guide channels, thereby causing the foaming material to foam.

[0018] According to some embodiments of this disclosure, the foaming treatment of the foam material based on the foaming guiding structure further includes:

[0019] The substrate layer, into which the foaming agent is injected, is placed in the mold cavity;

[0020] The foaming material is foamed sequentially using high-pressure foaming and low-pressure foaming methods. The high-pressure foaming is performed at a first preset temperature and a first preset pressure for a first preset time. The low-pressure foaming is performed at a second preset temperature and a second preset pressure for a second preset time.

[0021] According to some embodiments of this disclosure, the first preset pressure is greater than the second preset pressure, the first preset temperature is greater than the second preset temperature, and the first preset duration is less than the second preset duration.

[0022] The method for manufacturing a polishing pad provided in this embodiment involves setting a foaming guide structure on the substrate layer before foaming the substrate layer. The foaming process of the foaming material is guided by the guide channels of the foaming guide structure, allowing the foaming material to foam along the extension direction of the guide channels. This improves the uniformity and orientation of the overall foaming of the foaming material, ensuring that the pore size formed in the polishing layer of the resulting polishing pad is uniform in this extension direction, and that the cross-sectional area of ​​the pores at various locations along this extension direction is more consistent. Therefore, even if the polishing layer wears down during long-term use of the polishing pad, there will be no residue retention due to large pores in the polishing layer. This effectively prevents damage to the surface of the semiconductor structure during polishing, thereby improving the production yield of the semiconductor structure.

[0023] After reading and understanding the accompanying diagrams and detailed descriptions, the other aspects can be understood. Attached Figure Description

[0024] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present disclosure and, together with the description, serve to explain the principles of these embodiments. In these drawings, similar reference numerals are used to denote similar elements. The drawings described below are some embodiments of the present disclosure, but not all embodiments. Other drawings will be readily available to those skilled in the art based on these drawings without inventive effort.

[0025] Figure 1 This is an electron microscope image of the polished layer in the related technology;

[0026] Figure 2 This is a structural diagram of the foamed material in a method for manufacturing an abrasive pad according to an exemplary embodiment, when the foaming material is not foamed.

[0027] Figure 3 This is a structural diagram illustrating a method for manufacturing an abrasive pad according to an exemplary embodiment, showing the formation of a foamed guiding structure.

[0028] Figure 4 yes Figure 3 Enlarged view of point A in the middle;

[0029] Figure 5 This is a structural diagram of the foamed material after foaming, illustrating a method for manufacturing an abrasive pad according to an exemplary embodiment;

[0030] Figure 6 This is a cross-sectional view of the foamed material after foaming, in a direction perpendicular to the substrate layer, according to an exemplary embodiment of a method for manufacturing an abrasive pad.

[0031] Figure 7 This is a structural diagram of an abrasive pad after removing the foaming guide structure, according to an exemplary embodiment of a method for manufacturing an abrasive pad;

[0032] Figure 8 This is a structural diagram of an abrasive pad forming grooves, illustrating a method for manufacturing an abrasive pad according to an exemplary embodiment;

[0033] Figure 9 This is a cross-sectional view of an abrasive pad with grooves formed, illustrating a method for manufacturing an abrasive pad according to an exemplary embodiment;

[0034] Figure 10 This is an electron microscope image of the abrasive layer of an abrasive pad formed according to an exemplary embodiment of the abrasive pad manufacturing method.

[0035] Figure 11 This is a flowchart illustrating a method for manufacturing an abrasive pad according to an exemplary embodiment.

[0036] Figure label:

[0037] 1. Abrasive pad; 2. Substrate layer; 201. Foaming material; 202. Adhesive layer; 3. Base; 4. Foaming guide structure; 5. Guide channel; 6. Groove; 7. Mesh structure; 701. First support strip; 702. Second support strip; 8. Mesh holes; 9. Abrasive layer; 10. Backing adhesive layer. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions in the disclosed embodiments will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without creative effort are within the scope of protection of this disclosure. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this disclosure can be arbitrarily combined with each other.

[0039] Figure 1 Electron micrographs of the polishing layer of an polishing pad in the related art are shown, such as... Figure 1 As shown, the polishing layer in the related technology has a porous structure, and the pore size formed by the porous structure is mostly uneven. During the long-term polishing process of the polishing pad, the residue generated during the polishing process can easily remain in the larger pores of the polishing layer. Such residue can easily have an adverse effect on the subsequent polishing process of the semiconductor structure, such as forming scratches on the surface of the semiconductor structure, thereby affecting the yield of the semiconductor structure.

[0040] Based on this, this disclosure provides a method for manufacturing a polishing pad. Before foaming the substrate layer, a foaming guide structure is provided on the substrate layer. The foaming process of the foaming material is guided by the guide channels of the foaming guide structure, allowing the foaming material to foam along the extension direction of the guide channels. This improves the uniformity and orientation of the overall foaming of the foaming material, thereby ensuring that the pore size formed in the polishing layer of the resulting polishing pad is uniform in this extension direction, and that the cross-sectional area of ​​the pores at various locations in this extension direction is more consistent. Therefore, during the long-term use of the polishing pad, even if the polishing layer wears down, there will be no problem of residue retention due to the large pores in the polishing layer. This effectively avoids damage to the surface of the semiconductor structure during the polishing process, thereby improving the production yield of the semiconductor structure.

[0041] To better understand this solution, the application scenarios of the polishing pad are introduced here: In device manufacturing processes, such as the preparation of semiconductor structures, chemical mechanical polishing (CMP) systems are usually used to polish the surface of semiconductor structures. The working mechanism is to control the polishing pad to move downward to contact the surface of the semiconductor structure and to control the polishing pad to rotate around the axis to achieve the polishing of the semiconductor structure surface.

[0042] This disclosure provides a method for manufacturing an abrasive pad in one exemplary embodiment, such as... Figure 11 As shown, the method for manufacturing the abrasive pad includes the following steps:

[0043] Step S100: Provide a substrate layer, at least a portion of the surface of the substrate layer being a foamed material.

[0044] like Figure 2 As shown, and refer to Figure 9 The substrate layer 2 is used to form a mask layer for the abrasive pad 1. The substrate layer 2 may have a portion of its surface covered by foamed material 201, or it may have its entire surface covered by foamed material 201. Exemplarily, the entire substrate layer 2 may be composed of foamed material 201, or, as... Figure 2 As shown, the substrate layer 2 includes an adhesive layer 202 and a foam material 201 covering the adhesive layer 202. The adhesive layer 202 is used to fix the position of the foam material 201.

[0045] The bottom surface of the substrate layer 2 can be provided with the substrate 3 and the adhesive layer 10 stacked sequentially. The substrate 3 can be formed on top of the adhesive layer 10, and the substrate layer 2 can be formed on the surface of the substrate 3 away from the adhesive layer 10. For example, the material of the substrate 3 can be a soft material such as a rubber layer to provide good cushioning when polishing the semiconductor structure, and the adhesive layer 10 can be, for example, double-sided adhesive to achieve mutual adhesion between the polishing pad 1 and the polishing head.

[0046] Step S200: A foaming guide structure is provided on the substrate layer, the foaming guide structure having multiple guide channels.

[0047] like Figure 3 and Figure 4 As shown, the foaming guide structure 4 is used to limit the foaming direction of the foaming material 201 during the foaming process, so that the foaming material 201 can foam along the direction of the guide channel 5 during the foaming process. Continuing to refer to... Figure 3 The guide channels 5 in the foamed guide structure 4 can be arranged evenly in an array, or the guide channels 5 can be irregularly distributed. This embodiment does not limit this.

[0048] For example, the cross-sectional shape of the guide channel 5 can be circular, square, pentagonal, hexagonal, elliptical, etc. This embodiment does not limit this. Here, the cross-sectional shape of the guide channel 5 is the cross-sectional shape of the guide channel 5 obtained by cutting a plane parallel to the surface of the substrate layer 2.

[0049] Step S300: Based on the foaming guide structure, the foaming material is foamed so that the foaming material foams along each guide channel. The foaming guide structure is removed to obtain the grinding pad. The foaming structure obtained by foaming the foaming material forms the grinding layer of the grinding pad.

[0050] Among them, such as Figure 5 and Figure 6 As shown, the foaming material 201 is foamed along the guide channel 5 on the foaming guide structure 4. After removing the foaming guide structure 4, the foamed structure obtained by foaming the foaming material 201 is formed. Figures 7-9 The polishing layer 9 of the polishing pad 1 is used to contact the surface of the semiconductor structure and to polish the surface of the semiconductor structure.

[0051] It should be noted that the reference Figures 5-7 During the removal of the foaming guide structure 4, the foaming material 201 that enters the guide channel 5 can also be removed at the same time as the foaming guide structure 4 is removed.

[0052] For example, by weight percentage, the foam material 201 may include the following components: 10%–15% crosslinking agent, 25%–35% isocyanate, 40%–50% polyol, 8%–30% chain extender, and 2%–4% additives. The surface hardness and elasticity of the abrasive pad 1 formed by the foam material 201 can be adjusted by adjusting the proportions of the crosslinking agent, isocyanate, polyol, chain extender, and additives. When the crosslinking agent reacts with the isocyanate to grow the molecular chain, it induces a branched structure. This branched structure further reacts with the chain extender to form a network structure. The foamed material 201 made from the components in the embodiments of this disclosure has a hardness in the range of 45 to 65 Shore hardness D (preferably 55-60 Shore hardness D), an elongation in the range of 250% to 360% (preferably 280% to 320%), a density in the range of 0.6 to 0.8 g / cc, and a modulus in the range of 30,000 to 42,000 kg / cm³. 2 Within the range, the tensile stress is between 160 and 310 kg / cm². 2 Within the range. The abrasive layer 9 of the abrasive pad 1 made from the above components has the characteristics of high elongation and high hardness, so the abrasive layer 9 has good wear resistance.

[0053] The crosslinking agent may include one or more of dipentaerythritol (DPE), 4,4'-methylene-bis-(2-chloroaniline) [MOCA], etc.; the polyol may be one or two of polytetramethylene ether glycol (PTMG) and polyethylene glycol adipate (PEGA). The chain extender may include one or two of 1,4-butanediol (BDO) and ethylene glycol (EG); the additives include one or more of surfactants, fillers, catalysts, processing aids, antioxidants, stabilizers, lubricants, and conductive additives. The conductive additive may be one or more of carbon nanotubes, carbon nanoparticles, and alumina particles.

[0054] For example, the foam material 201 may further include 1%-5% abrasive, which can be injected during the subsequent foaming process of the foam material 201 and fill the pores of the foam material 201 to further improve the grinding performance of the grinding layer 9 and improve the uniformity of the pores of the grinding layer 9. The abrasive may include one or more materials with high hardness such as diamond and cesium dioxide. Because diamond and cesium dioxide have high hardness, filling them into the polyurethane bubbles can effectively increase the structural hardness and wear resistance of the grinding layer 9.

[0055] refer to Figure 10 and compare Figure 1 Compared to the prior art, the polishing pad 1 formed by the embodiments of this disclosure has a uniform and regular pore extension direction, and the pore size is not significantly different. In this embodiment, before foaming the substrate layer 2, a foaming guide structure 4 is provided on the substrate layer 2. The foaming process of the foaming material 201 is guided by the guide channel 5 of the foaming guide structure 4, which allows the foaming material 201 to foam along the extension direction of the guide channel 5, improving the uniformity and orientation of the overall foaming of the foaming material 201. This ensures that the pore size formed in the polishing layer 9 of the resulting polishing pad 1 is uniform in this extension direction, and the cross-sectional area of ​​the pores at various positions in the extension direction is more consistent. During the long-term use of the polishing pad 1, even if the polishing layer 9 wears down, there will be no residue retention due to the large pores in the polishing layer 9. This effectively avoids damage to the surface of the semiconductor structure during the polishing process, thereby improving the production yield of the semiconductor structure.

[0056] In one embodiment, after removing the foamed guiding structure, the method of manufacturing the abrasive pad may further include: forming grooves on the surface of the foamed material after removing the foamed guiding structure for accommodating the abrasive slurry.

[0057] refer to Figure 8 and combined Figure 9 One or more grooves 6 may be provided on the grinding layer 9. The shape of the grooves 6 may be, for example, concentric circles, non-concentric circles, ellipses, polygonal rings, spiral rings, irregular rings, parallel lines, radial lines, radial arcs, spirals, dots, XY grids, etc., but is not limited thereto.

[0058] For example, selective laser sintering can be used to form grooves 6 distributed along different trajectories on the top surface of the polishing pad. The processing accuracy of selective laser sintering is less than 0.07 mm, therefore, selective sintering can meet the processing accuracy required for the polishing pad 1. Of course, it is understood that methods other than selective laser sintering can also be used to form the grooves 6, such as die-cutting, and this embodiment does not impose any limitations on this.

[0059] In this embodiment, the groove 6 can ensure the bearing capacity of the grinding layer 9 for the grinding fluid and the flow capacity of the grinding fluid, thereby giving the grinding layer 9 a high grinding efficiency.

[0060] In an exemplary embodiment of this disclosure, step S300 includes the following steps:

[0061] Step S310: Inject foaming agent into each guide channel so that the foaming agent comes into contact with the foaming material through the guide channel, so that the foaming material foams.

[0062] The process in this step can be referenced. Figures 3 to 5 The foaming agent generates and releases volatile gases, which can form bubbles in the foaming material 201, assisting in the mechanical foaming of the foaming material 201 and improving the pore uniformity during the foaming process. The foaming agent can be, for example, a solid-phase foaming agent with a porous structure, including one or more of volatile liquid foaming agents and inert gases; this embodiment is not limited to this. The solid-phase foaming agent can be thermally expandable microcapsules, which are obtained by heating and expanding thermally expandable microcapsules, i.e., the structure of the thermally expandable microcapsules is an expanded microsphere. Due to their uniform particle size, they can achieve uniform control of pore size.

[0063] Exemplarily, thermally expandable microcapsules may include a shell of thermoplastic resin and a blowing agent encapsulated within the shell. The thermoplastic resin may be selected from at least one of vinylidene chloride copolymers, acrylonitrile copolymers, methacrylonitrile copolymers, and acrylic copolymers. Furthermore, the blowing agent may be at least one of a hydrocarbon having 1 to 7 carbon atoms.

[0064] Step S320: Place the substrate layer with the foaming agent injected into the mold cavity.

[0065] The mold cavity (not shown in the figure) is a closed, temperature-adjustable cavity. During the foaming process of the foaming agent, the foaming conditions for the foaming material 201 can be provided by changing the pressure and temperature of the mold cavity.

[0066] For example, the pressure inside the mold cavity can be changed by vacuuming, thereby changing the pressure on the foam material 201. The temperature of the mold cavity and the foam material 201 inside the mold cavity can be changed quickly by heating and cooling devices.

[0067] Step S330: The foaming material is foamed sequentially using high-pressure foaming and low-pressure foaming. The high-pressure foaming condition is to foam for a first preset time at a first preset temperature and a first preset pressure. The low-pressure foaming condition is to foam for a second preset time at a second preset temperature and a second preset pressure.

[0068] It should be noted that the first preset pressure is greater than the second preset pressure, the first preset temperature is greater than the second preset temperature, and the first preset time is less than the second preset time. By combining the rapid high-pressure foaming method with the gentle low-pressure foaming method, the pore uniformity and wear resistance of the foam material 201 can be effectively improved.

[0069] For example, the first preset pressure can be 8-20 MPa, the second preset pressure can be 0.5-1 MPa, the first preset temperature can be 170-200℃, the second preset temperature can be 30-50℃, the first preset duration can be 0.2-0.5 h, and the second preset duration can be 2-3 h.

[0070] Step S340: Remove the foaming material and foaming guide structure above the grinding layer by mechanical grinding or by chemical etching.

[0071] The surface of the polishing layer 9, formed by chemical etching and mechanical polishing, has good flatness. In practical applications, it can avoid the problems of uneven surface polishing and poor polishing effect of semiconductor structures, thereby improving the production yield of semiconductor structures.

[0072] When using chemical etching to remove the foamed material 201 and the foamed guide structure 4 located above the grinding layer 9, since the foamed guide structure 4 has strong corrosion resistance, it can be removed after partially removing the foamed guide structure 4. For example, the grinding pad 1, which is solidified after foaming, can be inverted, and the entire foamed guide structure 4 can be immersed in a chemical etching solution. The solution can then be used to etch the foamed material 201. Since the grinding pad 1 is inverted, after the foamed material 201 covering the top surface of the foamed guide structure 4 away from the substrate layer 2 and the foamed material 201 located in each guide channel 5 are removed, the foamed guide structure 4 can automatically fall into the cavity used to hold the solution. Subsequently, the foamed guide structure 4 can be removed and cleaned to achieve secondary use of the foamed guide structure 4.

[0073] For example, laser processing can also be used to remove the foaming guide structure 4 and the foaming material 201 located above the abrasive layer 9.

[0074] In this embodiment, a foaming agent is injected into the foaming material 201 via the guide channel 5, and bubbles are generated in the foaming material 201 during the foaming process, increasing the total number of bubbles during the foaming process. This increases the number and density of pores in the foaming material 201 after foaming, thereby effectively improving the specific surface area of ​​the polishing layer 9 and the polishing efficiency of the polishing pad 1 on the semiconductor structure. In addition, the high-pressure foaming process can form a large number of microbubbles in a short time, and the microbubbles are evenly distributed in the foaming material 201. The foaming time of the foaming material 201 is extended by the low-pressure foaming process, and the microbubbles are enlarged and fused to further optimize the pore structure of the foaming material 201. In the above process, the foaming of the foaming material 201 is achieved by a combination of high-pressure and low-pressure foaming, which can give the polishing layer 9 good wear resistance and pore uniformity.

[0075] In some embodiments, the foamed guide structure 4 includes at least one layer of mesh structure 7, and the mesh holes 8 of the mesh structure 7 form guide channels 5.

[0076] The mesh structure 7 can be configured with only one layer. When the mesh structure 7 is configured with only one layer, the mesh holes 8 of the single-layer mesh structure 7 form the guide channel 5. The mesh structure 7 can also be configured with, for example, Figure 4The multi-layer structure shown can be configured with two, three, or four layers. When the mesh structure 7 is configured with multiple layers, the multi-layer mesh structures 7 are stacked, and the mesh holes 8 of the multi-layer mesh structures 7 are configured one-to-one and interconnected. For example, two adjacent mesh structures 7 can be bonded to each other with an adhesive layer to ensure the stability of the foamed guide structure 4 formed by the multi-layer mesh structure 7.

[0077] It is understandable that the height of the single-layer mesh structure 7 in the extension direction of the mesh hole 8 can be set before the production of the mesh structure 7, or the mesh structure 7 with a relatively low thickness can be mass-produced, and the number of mesh structures 7 can be set according to actual needs, such as the thickness of the foaming guide structure 4 when it is not foamed.

[0078] For example, when the foaming guide structure 4 is composed of a single-layer mesh structure 7, the thickness of the mesh structure 7 in the extension direction of the mesh holes 8 is 5μm-20μm, and when the foaming guide structure 4 is composed of a multi-layer mesh structure 7, the thickness of the mesh structure 7 in the extension direction of the mesh holes 8 is 55μm-80μm, but not limited thereto.

[0079] In this embodiment, by setting at least one layer of mesh structure 7 to limit the height of the mesh holes 8 in their extension direction, the foaming guide structure 4 has a larger extension distance in the extension direction of the mesh holes 8, thereby providing more expansion space for the foaming material 201. This ensures that the foaming material 201 can be evenly distributed in the area formed by the mesh holes 8, avoiding the risk of deformation or cracking of the foaming material 201 during the curing process. In addition, the directional mesh holes 8 can play a good guiding role in the foaming process of the foaming material 201, ensuring that the foaming material 201 can flow and diffuse in a specific direction, thereby effectively improving the orientation and uniformity of the abrasive pad 1 formed by the foaming material 201.

[0080] In some embodiments, continue to refer to Figure 4 The grid structure 7 may include interconnected first support bars 701 and second support bars 702, which are arranged intersectingly and at a predetermined angle. Grid holes 8 are formed between two adjacent first support bars 701 and two adjacent second support bars 702.

[0081] The first support bar 701 and the second support bar 702 can be movably connected, for example, they can be snapped together. Two adjacent first support bars 701 are parallel to each other, and two adjacent second support bars 702 are parallel to each other. The opening size of the mesh hole 8 can be adjusted by adjusting the spacing between two adjacent first support bars 701 and / or two second support bars 702.

[0082] For example, the materials of the first support strip 701 and the second support strip 702 may be the same or different. This embodiment does not limit this. The lengths of the multiple first support strips 701 may be different, and the lengths of the multiple second support strips 702 may be different, so as to ensure that the formed mesh structure 7 adapts to the size of the substrate layer 2.

[0083] In this embodiment, the opening size of the mesh hole 8 can be adjusted by adjusting the distance between adjacent first support bars 701, the distance between adjacent second support bars 702, and the distance between adjacent first support bars 701 and second support bars 702, thereby adjusting the opening size of the guide channel 5 to meet different process requirements for manufacturing the grinding pad. Additionally, this reduces the cost required to manufacture mesh structures 7 of different specifications.

[0084] In other embodiments, reference continues to be made. Figure 4 The grid structure 7 may include a substrate and a number of hole structures disposed on the substrate, the hole structures forming grid holes 8.

[0085] For example, the size of the substrate can be determined according to the size of the substrate layer 2, for example, the diameter of the substrate layer 2. After obtaining a substrate that matches the size of the substrate layer 2, a hole structure can be formed on the substrate by laser drilling. The hole structure is used to form a guide channel 5 to guide the foaming process of the foaming material 201.

[0086] In this embodiment, the mesh structure 7 is an integral structure, so the mesh structure 7 has good stability. During the foaming process of the foaming material 201, the mesh structure 7 will not shift under the pushing action of the foaming material 201. The size of the mesh holes 8 of the mesh structure 7 will never change. Therefore, the polishing layer 9 formed by foaming the mesh structure 7 can have a high yield, thereby effectively ensuring the polishing effect of the polishing pad 1 on the semiconductor structure.

[0087] In some embodiments, the material of the mesh structure 7 includes carbon fiber.

[0088] In this embodiment, carbon fiber is used to manufacture the mesh structure 7, which achieves high strength and lightweight, avoiding deformation of the mesh structure 7 during the foaming and curing process of the foamed material 201, thus preventing the grinding layer 9 from collapsing, and effectively ensuring the uniformity of the pores of the foamed guiding structure 4. Furthermore, carbon fiber has good corrosion resistance, preventing particles formed by corrosion of the foamed guiding structure 4 from embedding into the grinding layer 9 during subsequent removal, thereby ensuring the yield of the grinding layer 9 and preventing scratches on the semiconductor structure during the grinding process.

[0089] In other embodiments, the material of the mesh structure 7 can also be one or more of stable fibers such as polyaramid fiber, high-performance polymer fiber, and polyethylene fiber. For example, when the mesh structure 7 is composed of a first support strip 701 and a second support strip 702, the material of each individual first support strip 701 or second support strip 702 can be different from each other. A single first support strip 701 can be carbon fiber, polyaramid fiber, high-performance polymer fiber, or polyethylene fiber, and a single second support strip 702 can be carbon fiber, polyaramid fiber, high-performance polymer fiber, or polyethylene fiber. This embodiment does not impose such limitations. When the mesh structure 7 includes a substrate and a perforated structure disposed on the substrate, the material of the mesh structure 7 is one of stable fibers such as carbon fiber, polyaramid fiber, high-performance polymer fiber, and polyethylene fiber, in order to reduce the manufacturing difficulty of the mesh structure 7.

[0090] In some embodiments, the guide channel 5 is perpendicular to the surface of the substrate layer 2.

[0091] In this embodiment, reference Figure 3 The guide channel 5 is perpendicular to the surface of the substrate layer 2, meaning that the guide channel 5 is perpendicular to the unfoamed foamed material 201 on the surface of the substrate layer 2. This helps ensure good contact between the guide channel 5 and the foamed material 201 on the substrate surface, effectively improving foaming efficiency and avoiding the problem of inconsistent pore sizes in the formed grinding layer 9. This improves the uniformity of the grinding layer 9 formed by the foamed material 201 and also effectively improves the utilization rate of the foamed material 201, thereby improving the integrity of the foamed grinding layer 9. Furthermore, all guide channels 5 are perpendicular to the surface of the substrate layer 2, meaning that all guide channels 5 are arranged in the same direction. This ensures that the foamed material 201 can flow and diffuse in the vertical direction, thus ensuring the orientation of the pores in the grinding layer 9 formed by the foamed material 201.

[0092] In some embodiments, the size of the opening of the guide channel 5 is 2μm-20μm. This size can be used to characterize the maximum size between two points of the opening shape or cross-sectional shape of the guide channel 5, or its circumscribed circle size, etc., but is not limited thereto.

[0093] For example, the shape of the opening can be circular, rectangular, pentagonal, hexagonal, elliptical, etc., and this embodiment does not limit it.

[0094] When the opening shape of the guide channel 5 is circular, the size of the opening can be, for example, the diameter of the opening. When the shape of the guide channel 5 is rectangular, the size of the opening can be, for example, the length or width of the opening. When the shape of the guide channel 5 is pentagonal, hexagonal or other polygonal, the size of the opening can be, for example, the diameter of the inscribed circle or the circumscribed circle of the opening. When the shape of the guide opening is elliptical, the size of the opening can be, for example, the length of the major axis or the minor axis of the opening.

[0095] The size of the guide channel 5 can also be expressed by the dimension of the cross-section parallel to the surface of the substrate layer 2. In some cases, the opening shape of the guide channel 5 can be consistent with the shape of the cross-section.

[0096] In this embodiment, by setting the opening size of the guide channel 5 to the micrometer level, the gaps in the polishing layer 9 formed by the foaming material 201 can be smaller, thereby effectively avoiding the problem of particles entering the gaps and damaging the semiconductor structure to be polished.

[0097] In the description of this specification, references to the terms "embodiment," "exemplary embodiment," "some implementation," "illustrated implementation," "example," etc., refer to specific features, structures, materials, or characteristics described in connection with an implementation or example that are included in at least one implementation or example of this disclosure.

[0098] In this specification, the illustrative expressions of the terms used do not necessarily refer to the same implementation or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more implementations or examples.

[0099] In the description of this disclosure, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this disclosure.

[0100] It is understood that the terms "first," "second," etc., as used in this disclosure may be used to describe various structures, but these structures are not limited by these terms. These terms are only used to distinguish one structure from another.

[0101] In one or more accompanying drawings, the same elements are represented by similar reference numerals. For clarity, many parts in the drawings are not drawn to scale. Furthermore, certain well-known parts may not be shown. For simplicity, a structure obtained after several steps may be depicted in a single drawing. Many specific details of this disclosure, such as the structure, materials, dimensions, processing methods, and techniques of the devices, are described below to provide a clearer understanding of the disclosure. However, as those skilled in the art will understand, this disclosure may be implemented without adhering to these specific details.

[0102] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this disclosure, and are not intended to limit them. Although this disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this disclosure.

Claims

1. A method for manufacturing an abrasive pad, characterized in that, The method for manufacturing the abrasive pad includes: A substrate layer is provided, wherein at least a portion of the surface of the substrate layer is the material to be foamed; A foamed guiding structure is provided on the substrate layer. The foamed guiding structure has multiple guiding channels. The foamed guiding structure includes at least one layer of mesh structure. The mesh holes of the mesh structure constitute the guiding channels. The guiding channels are perpendicular to the surface of the substrate layer. A foaming agent is injected into each of the guide channels, and the foaming agent comes into contact with the material to be foamed through the guide channels; The material to be foamed is subjected to a foaming treatment to obtain a foamed structure, wherein the foaming agent foams the material to be foamed based on the foaming guide structure along the direction of each of the guide channels; The foamed guiding structure and the foamed structure entering the guiding channel are removed to obtain the abrasive pad, wherein the remaining foamed structure forms the abrasive layer of the abrasive pad; Abrasive is injected during the foaming process of the material to be foamed.

2. The method for manufacturing the abrasive pad according to claim 1, characterized in that, The material of the grid structure includes carbon fiber.

3. The method for manufacturing the abrasive pad according to claim 1 or 2, characterized in that, The size of the opening of the guide channel is 2μm-20μm.

4. The method for manufacturing the abrasive pad according to claim 1 or 2, characterized in that, After removing the foamed guiding structure, the method for manufacturing the abrasive pad further includes: Grooves are formed on the surface of the polishing layer to accommodate the polishing fluid.

5. The method for manufacturing the abrasive pad according to claim 4, characterized in that, The foamed guiding structure and the foamed structure entering the guiding channel are removed by mechanical grinding; or... The foamed guide structure and the foamed structure entering the guide channel are removed by chemical etching.

6. The method for manufacturing the abrasive pad according to claim 1, characterized in that, The foaming process for the foamed material further includes: The substrate layer, into which the foaming agent is injected, is placed in the mold cavity; The foaming material is foamed sequentially using high-pressure foaming and low-pressure foaming methods. The high-pressure foaming is performed at a first preset temperature and a first preset pressure for a first preset time. The low-pressure foaming is performed at a second preset temperature and a second preset pressure for a second preset time.

7. The method for manufacturing the abrasive pad according to claim 6, characterized in that, The first preset pressure is greater than the second preset pressure, the first preset temperature is greater than the second preset temperature, and the first preset duration is less than the second preset duration.

8. The method for manufacturing the abrasive pad according to claim 1, characterized in that, The material to be foamed comprises the following components: 10%–15% crosslinking agent, 25%–35% isocyanate, 40%–50% polyol, 8%–30% chain extender, and 2%–4% additives.

9. The method for manufacturing the abrasive pad according to claim 1, characterized in that, Foaming agents are solid-phase foaming agents with a porous structure.

10. The method for manufacturing the abrasive pad according to claim 1 or 8, characterized in that, The content of the abrasive is 1%-5%.

11. The method for manufacturing the abrasive pad according to claim 1, characterized in that, The cross-sectional shape of the guide channel is circular, square, pentagonal, hexagonal, or elliptical.

12. The method for manufacturing the abrasive pad according to claim 1, characterized in that, The material of the mesh structure is one or more of polyaramid fiber, high-performance polymer fiber, and polyethylene fiber.

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