A high-efficiency polishing wax-free pad for silicon wafer and its production process

Abstract

The application discloses a kind of silicon wafer high-efficiency polishing waxless pad and its production process, belong to waxless pad technical field, including basic substrate layer and adsorption polishing layer, basic substrate layer is provided with adsorption polishing layer.The application solves the problem that the existing waxless pad is relaxed and damaged when using due to the lack of internal support of the waxless pad, which reduces the polishing efficiency of the waxless pad.The application adds support base column and reinforcing strut in the base layer, and makes the reinforcing strut evenly distributed on the circumference of the support base column.The support base column and reinforcing strut can improve the support strength of the base layer.The support base column is inflated through the gas inlet, and the gas is discharged into the reinforcing strut through the support base column.The gas is discharged into the base layer through the exhaust hole on the reinforcing strut, which can make the base layer full and improve the support strength of the base layer.The waxless pad has high support strength, which can avoid relaxation and damage, and improve the polishing efficiency of the waxless pad.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wax-free pad, in particular to a high-efficiency polishing wax-free pad for silicon wafer and a production process thereof. BACKGROUND

[0002] In the processing of semiconductor materials, silicon wafers, as the basic materials of common semiconductor devices and integrated circuits, often need to be polished, and the quality of the polishing technology will directly affect the quality of the silicon wafer surface and the performance of the semiconductor device. Traditional polishing techniques mainly include wax polishing and wax-free polishing. Wax technology fixes the silicon wafer on the flat plate of a ceramic disc, and the ceramic disc is rotated on the polishing cloth by the polishing head during polishing, achieving the polishing purpose under the action of mechanical pressure and polishing liquid. It is found in practice that this wax polishing has the defects of wax pollution and low polishing precision. With the rapid development of electronic technology and the increasing integration of large-scale integrated circuits, people's requirements for semiconductor devices are becoming more and more stringent, so the advantages of wax-free polishing are gradually emerging.

[0003] A wax-free pad for polishing is disclosed in Chinese Patent No. CN112873074B, which includes a base disc, a wafer placement hole, a clamping pad, and a wax-free adsorption pad. The surface of the base disc is provided with at least one wafer placement hole, and the wafer placement hole is provided with a wax-free adsorption pad for adsorbing the wafer. At least one layer of clamping pad is provided between the wax-free adsorption pad and the inner bottom of the wafer placement hole. A composite resin is produced by reacting epoxy resin and polyurethane prepolymer, and the composite resin is used as an adhesive layer. The adhesive layer has the properties of both epoxy resin and polyurethane resin, with high viscosity and elasticity, and can be well bonded with the carbon fiber layer and the adsorption layer, avoiding delamination of the wax-free adsorption pad. However, the above-mentioned patent has the following defects:

[0004] The existing wax-free pad lacks internal support, resulting in low support strength of the wax-free pad, which is prone to damage and reduces the polishing efficiency of the wax-free pad. SUMMARY

[0005] The present application provides a high-efficiency polishing wax-free pad for silicon wafer and a production process thereof, which can improve the support strength of the wax-free pad, avoid damage due to relaxation, and improve the polishing efficiency of the wax-free pad, solving the problems raised in the background technology.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0007] A high-efficiency polishing wax-free pad for silicon wafer, comprising a base substrate layer and an adsorption polishing layer, the base substrate layer is provided with an adsorption polishing layer, and the thickness ratio of the base substrate layer and the adsorption polishing layer is 1:1-2.

[0008] Preferably, the base substrate layer comprises the following raw materials in mass fraction: modified epoxy resin 30-40 parts, carbon fiber 10-30 parts, filler 10-20 parts, and curing agent 20-30 parts.

[0009] Preferably, the adsorption polishing layer comprises a base layer, a polishing layer, and an adsorption layer, the base layer is arranged on the base substrate layer, the polishing layer is arranged on the base layer, the polishing layer is provided with silicon wafer placing grooves, and the adsorption layer is arranged in the silicon wafer placing grooves.

[0010] Preferably, the base layer is provided with a support and reinforcement assembly, the support and reinforcement assembly comprises a support column and a reinforcement strut, the support column is arranged in the base layer, the support column is uniformly provided with the reinforcement struts on the circumferential surface, and the reinforcement struts are used to enhance the support strength of the base layer.

[0011] Preferably, the support column and the reinforcement strut are in communication, the support column is provided with an air inlet, the air inlet is sealingly connected to the base layer, and the air inlet penetrates the polishing layer.

[0012] Preferably, the reinforcement struts are arranged in the base layer, the bottom and the top of the reinforcement struts are provided with exhaust holes, and the exhaust holes are equally spaced.

[0013] Preferably, the polishing layer comprises the following raw materials in mass fraction: fluorine-containing polyurethane 2-10 parts, thermoplastic polyurethane 0-4 parts, mixed fiber material 1-2 parts, carboxymethyl cellulose glue 1-3 parts, abrasive adhesive 25-35 parts, organic solvent 55-70 parts, and auxiliary agent 0-0.3 parts.

[0014] Preferably, the adsorption layer comprises the following raw materials in mass fraction: fluorine-containing polyurethane 2-20 parts, thermoplastic polyurethane 1-10 parts, zinc oxide 0-2 parts, activated carbon fiber 0-3 parts, organic solvent 65-95 parts, and auxiliary agent 0-0.5 parts.

[0015] According to another aspect of the present application, a production process of the high-efficiency polishing wax-free pad for silicon wafers is provided, comprising the following steps:

[0016] S1, producing a base substrate layer:

[0017] The modified epoxy resin, carbon fiber, filler, and curing agent are added into an extruder, and after stirring, mixing, plasticizing, and compacting by the extruder, a pre-product with a certain shape is extruded, and the pre-product is repeatedly extruded and stretched by a calender to form a base substrate layer with uniform thickness.

[0018] S2, producing an adsorption polishing layer:

[0019] Supporting base columns and reinforcing support rods which are communicated are processed in the base layer, and an air inlet is processed on the supporting base column, and exhaust holes are processed at the bottom and top of the reinforcing support rod;

[0020] The fluorine-containing polyurethane, the thermoplastic polyurethane, the mixed fiber material, the carboxymethyl cellulose glue, the abrasive adhesive, the organic solvent and the auxiliary are added into the extruder, after stirring, mixing, plasticizing and compacting by the extruder, a pre-product of a certain shape is extruded, and the pre-product is repeatedly extruded and stretched by the calender to form the polishing layer with uniform thickness;

[0021] The fluorine-containing polyurethane, the thermoplastic polyurethane, the zinc oxide, the activated carbon fiber, the organic solvent and the auxiliary are added into the extruder, after stirring, mixing, plasticizing and compacting by the extruder, a pre-product of a certain shape is extruded, and the pre-product is repeatedly extruded and stretched by the calender to form the adsorbing layer with uniform thickness;

[0022] The silicon wafer placing groove is processed on the polishing layer, the adsorbing layer is processed in the silicon wafer placing groove, and the polishing layer is processed on the surface of the base layer to form the adsorbing polishing layer.

[0023] S3, producing the waxless pad:

[0024] The produced adsorbing polishing layer is placed on the base substrate layer, and after laminating, the waxless pad is formed.

[0025] Compared with the prior art, the beneficial effects of the present application are:

[0026] The supporting strength of the base layer is improved by adding the supporting base column and the reinforcing support rod in the base layer, and uniformly distributing the reinforcing support rod on the circumferential surface of the supporting base column, the supporting strength of the base layer is improved by inflating the supporting base column through the air inlet, discharging to the reinforcing support rod through the supporting base column, discharging to the base layer through the exhaust holes on the reinforcing support rod, the base layer is filled, the supporting strength of the waxless pad is high, the waxless pad is prevented from being damaged due to relaxation, and the polishing efficiency of the waxless pad is improved. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 It is a front view of the high-efficiency polishing waxless pad for silicon wafers of the second embodiment of the present application;

[0028] Figure 2 It is a front view of the adsorbing polishing layer of the second embodiment of the present application;

[0029] Figure 3 It is an exploded view of the adsorbing polishing layer of the second embodiment of the present application;

[0030] Figure 4 It is a front view of the high-efficiency polishing waxless pad for silicon wafers of the first embodiment of the present application;

[0031] Figure 5 A positive exploded view of the base layer and the polishing layer for the first embodiment of the present application;

[0032] Figure 6 A partial exploded view of the adsorptive polishing layer for the first embodiment of the present application;

[0033] Figure 7 A positive exploded view of the adsorptive polishing layer for the first embodiment of the present application;

[0034] Figure 8 A positive view of the support enhancement assembly for the first embodiment of the present application.

[0035] In the figure: 1, base substrate layer; 2, adsorptive polishing layer; 21, base layer; 22, polishing layer; 221, silicon wafer placement slot; 23, adsorptive layer; 24, support enhancement assembly; 241, support column; 2411, air inlet; 242, enhancement strut; 2421, air outlet. DETAILED DESCRIPTION

[0036] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0037] In order to solve the problem that the existing wax-free pad lacks internal support, resulting in low support strength of the wax-free pad, the wax-free pad is easily damaged and the polishing efficiency of the wax-free pad is reduced when the wax-free pad is used, please refer to Figures 1-8 The technical solutions of the present embodiment are as follows:

[0038] Embodiment one

[0039] A high-efficiency polishing wax-free pad for silicon wafers comprises a base substrate layer 1 and an adsorptive polishing layer 2, the adsorptive polishing layer 2 is arranged on the base substrate layer 1, and the thickness ratio of the base substrate layer 1 to the adsorptive polishing layer 2 is 1:2.

[0040] In the present embodiment, the base substrate layer 1 comprises the following raw materials in mass fraction: modified epoxy resin 30 parts, carbon fiber 10 parts, filler 10 parts and curing agent 20 parts.

[0041] In the present embodiment, the adsorptive polishing layer 2 comprises a base layer 21, a polishing layer 22 and an adsorptive layer 23, the base layer 21 is arranged on the base substrate layer 1, the polishing layer 22 is arranged on the base layer 21, the silicon wafer placement slot 221 is formed in the polishing layer 22, and the adsorptive layer 23 is arranged in the silicon wafer placement slot 221.

[0042] In the embodiment, the support enhancement assembly 24 is arranged in the base layer 21, the support enhancement assembly 24 comprises support columns 241 and enhancement struts 242, the support columns 241 are arranged in the base layer 21, and the enhancement struts 242 are uniformly distributed on the circumferential surface of the support columns 241, and the enhancement struts 242 are used to enhance the support strength of the base layer 21.

[0043] It should be noted that, by additionally arranging the support columns 241 and the enhancement struts 242 in the base layer 21, and uniformly distributing the enhancement struts 242 on the circumferential surface of the support columns 241, the support strength of the base layer 21 can be improved by the support columns 241 and the enhancement struts 242, so that the support strength of the wax-free pad is high, the wax-free pad can be prevented from being damaged due to relaxation, and the polishing efficiency of the wax-free pad can be improved.

[0044] In the embodiment, the support columns 241 and the enhancement struts 242 are communicated, the support columns 241 are provided with air inlets 2411, the air inlets 2411 are sealingly connected to the base layer 21, and the air inlets 2411 penetrate the polishing layer 22.

[0045] In the embodiment, the enhancement struts 242 are located in the base layer 21, the bottom and the top of the enhancement struts 242 are provided with air exhaust holes 2421, and the air exhaust holes 2421 are equally spaced.

[0046] It should be noted that, by inflating the support columns 241 through the air inlets 2411, the air is discharged into the enhancement struts 242 through the support columns 241, and the air is discharged into the base layer 21 through the air exhaust holes 2421 on the enhancement struts 242, so that the base layer 21 can be filled, the support strength of the base layer 21 can be improved, the support strength of the wax-free pad is high, the wax-free pad can be prevented from being damaged due to relaxation, and the polishing efficiency of the wax-free pad can be improved.

[0047] In the embodiment, the polishing layer 22 comprises the following raw materials in mass fraction: 10 parts of fluorine-containing polyurethane, 4 parts of thermoplastic polyurethane, 2 parts of mixed fiber material, 3 parts of carboxymethyl cellulose glue, 35 parts of abrasive adhesive, 70 parts of organic solvent, and 0.3 parts of additive.

[0048] In the embodiment, the adsorption layer 23 comprises the following raw materials in mass fraction: 20 parts of fluorine-containing polyurethane, 10 parts of thermoplastic polyurethane, 2 parts of zinc oxide, 3 parts of activated carbon fiber, 95 parts of organic solvent, and 0.5 parts of additive.

[0049] In order to better show the production process of the high-efficiency polishing wax-free pad for silicon wafers, the embodiment provides a production process of the high-efficiency polishing wax-free pad for silicon wafers according to the above, which comprises the following steps:

[0050] S1, producing a base substrate layer 1:

[0051] The modified epoxy resin, carbon fiber, filler and curing agent are added into the extruder, and after stirring, mixing, plasticizing and compacting by the extruder, a pre-product of a certain shape is extruded, and the pre-product is repeatedly extruded and stretched by the calender to form the base substrate layer 1 with uniform thickness;

[0052] S2, producing the adsorption polishing layer 2:

[0053] The support column 241 and the reinforcing strut 242 are processed in the base layer 21, and the gas inlet 2411 is processed on the support column 241, and the exhaust hole 2421 is processed at the bottom and top of the reinforcing strut 242;

[0054] The fluorine-containing polyurethane, thermoplastic polyurethane, mixed fiber material, carboxymethyl cellulose glue, abrasive adhesive, organic solvent and auxiliary agent are added into the extruder, and after stirring, mixing, plasticizing and compacting by the extruder, a pre-product of a certain shape is extruded, and the pre-product is repeatedly extruded and stretched by the calender to form the polishing layer 22 with uniform thickness;

[0055] The fluorine-containing polyurethane, thermoplastic polyurethane, zinc oxide, activated carbon fiber, organic solvent and auxiliary agent are added into the extruder, and after stirring, mixing, plasticizing and compacting by the extruder, a pre-product of a certain shape is extruded, and the pre-product is repeatedly extruded and stretched by the calender to form the adsorption layer 23 with uniform thickness;

[0056] The silicon wafer placing groove 221 is processed on the polishing layer 22, and the adsorption layer 23 is processed in the silicon wafer placing groove 221, and the polishing layer 22 is processed on the surface of the base layer 21 to form the adsorption polishing layer 2;

[0057] S3, producing the wax-free pad:

[0058] The produced adsorption polishing layer 2 is placed on the base substrate layer 1, and after laminating, the wax-free pad is formed.

[0059] Example two

[0060] A silicon wafer high-efficiency polishing wax-free pad comprises a base substrate layer 1 and an adsorption polishing layer 2, the base substrate layer 1 is provided with the adsorption polishing layer 2, and the thickness ratio of the base substrate layer 1 and the adsorption polishing layer 2 is 1:2.

[0061] In this embodiment, the base substrate layer 1 comprises the following raw materials in mass fraction: modified epoxy resin 30 parts, carbon fiber 10 parts, filler 10 parts and curing agent 20 parts.

[0062] In the embodiment, the adsorbing polishing layer 2 comprises a base layer 21, a polishing layer 22 and an adsorbing layer 23, the base layer 21 is arranged on the base substrate layer 1, the polishing layer 22 is arranged on the base layer 21, the silicon wafer placing groove 221 is arranged on the polishing layer 22, and the adsorbing layer 23 is arranged in the silicon wafer placing groove 221.

[0063] In the embodiment, the base layer 21 is provided with a support and reinforcement assembly 24, the support and reinforcement assembly 24 comprises a support column 241 and a reinforcement strut 242, the support column 241 is arranged in the base layer 21, and the reinforcement struts 242 are uniformly distributed on the circumferential surface of the support column 241, and the reinforcement struts 242 are used to enhance the support strength of the base layer 21.

[0064] It should be noted that, by additionally arranging the support column 241 and the reinforcement strut 242 in the base layer 21 and uniformly distributing the reinforcement struts 242 on the circumferential surface of the support column 241, the support strength of the base layer 21 can be improved by the support column 241 and the reinforcement strut 242, so that the support strength of the wax-free pad is high, and the wax-free pad can be prevented from being damaged due to relaxation, and the polishing efficiency of the wax-free pad can be improved.

[0065] In the embodiment, the polishing layer 22 comprises the following raw materials in mass fraction: 10 parts of fluorine-containing polyurethane, 4 parts of thermoplastic polyurethane, 2 parts of mixed fiber material, 3 parts of carboxymethyl cellulose glue, 35 parts of abrasive adhesive, 70 parts of organic solvent and 0.3 parts of auxiliary agent.

[0066] In the embodiment, the adsorbing layer 23 comprises the following raw materials in mass fraction: 20 parts of fluorine-containing polyurethane, 10 parts of thermoplastic polyurethane, 2 parts of zinc oxide, 3 parts of activated carbon fiber, 95 parts of organic solvent and 0.5 parts of auxiliary agent.

[0067] Compared with the first embodiment, the structure of the air inlet 2411 and the exhaust hole 2421 is cancelled in the second embodiment, and the same production process as the first embodiment is used to produce the wax-free pad, and the production steps of the air inlet 2411 and the exhaust hole 2421 are cancelled accordingly.

[0068] Comparative example

[0069] A kind of silicon wafer high-efficiency polishing wax-free pad, including base substrate layer 1 and adsorbing polishing layer 2, base substrate layer 1 is provided with adsorbing polishing layer 2, and the thickness ratio of base substrate layer 1 and adsorbing polishing layer 2 is 1:2.

[0070] In the embodiment, the base substrate layer 1 comprises the following raw materials in mass fraction: 30 parts of modified epoxy resin, 10 parts of carbon fiber, 10 parts of filler and 20 parts of curing agent.

[0071] In the embodiment, the adsorbing polishing layer 2 comprises a base layer 21, a polishing layer 22 and an adsorbing layer 23, the base layer 21 is arranged on the base substrate layer 1, the polishing layer 22 is arranged on the base layer 21, the silicon wafer placing groove 221 is arranged on the polishing layer 22, and the adsorbing layer 23 is arranged in the silicon wafer placing groove 221.

[0072] In the embodiment, the polishing layer 22 comprises the following raw materials in mass fraction: 10 parts of fluorine-containing polyurethane, 4 parts of thermoplastic polyurethane, 2 parts of mixed fiber material, 3 parts of carboxymethyl cellulose glue, 35 parts of abrasive adhesive, 70 parts of organic solvent and 0.3 parts of auxiliary agent.

[0073] In the embodiment, the adsorbing layer 23 comprises the following raw materials in mass fraction: 20 parts of fluorine-containing polyurethane, 10 parts of thermoplastic polyurethane, 2 parts of zinc oxide, 3 parts of activated carbon fiber, 95 parts of organic solvent and 0.5 parts of auxiliary agent.

[0074] Compared with the second embodiment, the structure of the support enhancement assembly 24 is cancelled in the comparative example, and the same production process as that of the second embodiment is adopted to produce the wax-free pad, and the production step of the support enhancement assembly 24 is cancelled accordingly.

[0075] The wax-free pads produced in the first and second embodiments and the comparative example are subjected to performance test, and the performance test results of the wax-free pads are shown in Table 1.

[0076] Table 1: Performance test results of the wax-free pad

[0077]

[0078]

[0079] Therefore, it can be known from the above table that the wax-free pads produced in the first and second embodiments all have good support strength and anti-loose performance.

[0080] Among them, compared with the first embodiment, the support strength and anti-loose performance of the second embodiment are reduced, because the air inlet 2411 and the exhaust hole 2421 are not increased in the second embodiment, which leads to the reduction of the support strength and anti-loose performance of the wax-free pad, indicating that the air inlet 2411 and the exhaust hole 2421 can improve the support strength and anti-loose performance of the wax-free pad.

[0081] Among them, compared with the second embodiment, the support strength and anti-loose performance of the comparative example are reduced, because the support enhancement assembly is not increased in the comparative example, which leads to the reduction of the support strength and anti-loose performance of the wax-free pad, indicating that the support enhancement assembly can improve the support strength and anti-loose performance of the wax-free pad.

[0082] Therefore, by adding the support columns 241 and the reinforcing rods 242 in the base layer 21, and by uniformly distributing the reinforcing rods 242 on the circumferential surface of the support columns 241, the support strength of the base layer 21 can be improved by the support columns 241 and the reinforcing rods 242. By filling the support columns 241 with air through the air inlet 2411, and by discharging the air from the support columns 241 to the reinforcing rods 242, and by discharging the air from the exhaust holes 2421 on the reinforcing rods 242 to the base layer 21, the base layer 21 can be filled, and the support strength of the base layer 21 can be improved, so that the support strength of the waxless pad is high, and the waxless pad can be prevented from being damaged due to relaxation, and the polishing efficiency of the waxless pad can be improved.

[0083] It should be noted that the relational terms herein such as first and second and the like are used solely to distinguish one from another entity or action, without necessarily requiring or implying any actual relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0084] Although the embodiments of the present application have been shown and described, it is to be understood that various changes, modifications, substitutions, and alterations can be made to the embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A high-efficiency wax-free polishing pad for silicon wafers, comprising a base substrate layer (1) and an adsorption polishing layer (2), characterized in that: An adsorption polishing layer (2) is provided on the base substrate layer (1), and a thickness ratio of the base substrate layer (1) to the adsorption polishing layer (2) is 1:1-2; The adsorption polishing layer (2) comprises a base layer (21), a polishing layer (22) and an adsorption layer (23); the base layer (21) is arranged on the basic substrate layer (1); the polishing layer (22) is arranged on the base layer (21); a silicon wafer placement groove (221) is provided on the polishing layer (22); and the adsorption layer (23) is arranged in the silicon wafer placement groove (221); A support reinforcement component (24) is provided in the base layer (21), the support reinforcement component (24) comprising a support base column (241) and a reinforcement support rod (242), the support base column (241) being provided in the base layer (21), the reinforcement support rod (242) being evenly distributed on the circumferential surface of the support base column (241), the reinforcement support rod (242) being used to enhance the support strength of the base layer (21); The support base column (241) and the reinforcing support rod (242) are connected to each other. An air inlet (2411) is provided on the support base column (241). The air inlet (2411) is sealed and connected to the base layer (21), and the air inlet (2411) passes through the polishing layer (22). The reinforcing support rod (242) is located in the base layer (21). The bottom and top of the reinforcing support rod (242) are both provided with exhaust holes (2421), and the exhaust holes (2421) are distributed at equal intervals.

2. A wax-free pad for high-efficiency polishing of silicon wafers according to claim 1, characterized in that: The basic substrate layer (1) comprises the following raw materials in parts by mass: 30-40 parts of modified epoxy resin, 10-30 parts of carbon fiber, 10-20 parts of filler and 20-30 parts of curing agent.

3. A wax-free pad for high-efficiency polishing of silicon wafers according to claim 2, characterized in that: The polishing layer (22) comprises the following raw materials in parts by mass: 2-10 parts of fluorine-containing polyurethane, 0-4 parts of thermoplastic polyurethane, 1-2 parts of mixed fiber material, 1-3 parts of carboxymethyl cellulose glue, 25-35 parts of abrasive adhesive, 55-70 parts of organic solvent and 0-0.3 parts of auxiliary agent.

4. A wax-free pad for high-efficiency polishing of silicon wafers according to claim 3, characterized in that: The adsorption layer (23) comprises the following raw materials in parts by mass: 2-20 parts of fluorine-containing polyurethane, 1-10 parts of thermoplastic polyurethane, 0-2 parts of zinc oxide, 0-3 parts of activated carbon fiber, 65-95 parts of organic solvent and 0-0.5 parts of auxiliary agent.

5. A production process for a high-efficiency wax-free polishing pad for silicon wafers according to claim 4, characterized in that: The steps include: S1. Production of base substrate layer (1): Adding modified epoxy resin, carbon fiber, filler and curing agent into an extruder, stirring, mixing, plasticizing and compacting in the extruder, extruding a pre-product of a certain shape, and repeatedly extruding and stretching the pre-product in a calender to form a base substrate layer (1) with uniform thickness; S2. Production of adsorption polishing layer (2): Processing interconnected support columns (241) and reinforcement rods (242) in the base layer (21), processing air inlets (2411) on the support columns (241), and processing exhaust holes (2421) on the bottom and top of the reinforcement rods (242); Fluorine-containing polyurethane, thermoplastic polyurethane, mixed fiber material, carboxymethyl cellulose glue, abrasive adhesive, organic solvent and additives are added to an extruder, stirred, mixed, plasticized and compacted by the extruder, and then a pre-product of a certain shape is extruded, and the pre-product is repeatedly extruded and stretched by a calender to form a polishing layer (22) with uniform thickness; Fluorine-containing polyurethane, thermoplastic polyurethane, zinc oxide, activated carbon fiber, organic solvent and additives are added to an extruder, stirred, mixed, plasticized and compacted by the extruder, and then a pre-product of a certain shape is extruded, and the pre-product is repeatedly extruded and stretched by a calender to form an adsorption layer with uniform thickness (23); A silicon wafer placement groove (221) is machined on the polishing layer (22), and an adsorption layer (23) is machined in the silicon wafer placement groove (221), and the polishing layer (22) is machined on the surface of the base layer (21) to form an adsorption polishing layer (2); S3, production of wax-free pads: The produced adsorption polishing layer (2) is placed on the base substrate layer (1) and laminated to form a wax-free pad.

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