Polishing pad and method of manufacturing the same

Abstract

To provide a polishing pad which is environmentally friendly and has physical properties achieving a level of a polishing rate required in a CMP process.SOLUTION: A polishing pad 100 comprises a top pad layer 10. The polishing pad 100 has a total biomass content of 1-50 wt.% as measured according to the ASTM D 6866 standard, and thus can be environmentally friendly.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The implementation relates to a polishing pad used in the chemical mechanical planarization (CMP) process of semiconductor devices, and more specifically to an environmentally friendly polishing pad containing biomass components and a manufacturing method thereof. [Background technology]

[0002] In the semiconductor manufacturing process, the chemical mechanical polishing (CMP) process is a process in which a semiconductor substrate such as a wafer is attached to a head and brought into contact with the surface of a polishing pad fixed on a platen, and the platen and the head are moved relative to each other to flatten uneven portions of the semiconductor substrate surface.

[0003] In the CMP process, the polishing pad is required to have stable physical properties since it has a significant impact on the surface processing quality of the semiconductor substrate. In particular, since the polishing rate of the CMP process can be sensitively affected by the components and physical properties of the polishing pad, it is necessary to optimize the components and physical properties of the polishing pad.

[0004] On the other hand, with the recent emergence of environmental issues such as climate change, public opinion is building that companies should take on social responsibility for building a sustainable society through ESG (Environment, Social, Governance) management, such as "carbon neutrality." As a result, various companies are attempting to manufacture a variety of products using biomass materials derived from plants, etc., instead of petroleum-based materials.

[0005] In line with this trend, attempts are being made to improve environmental friendliness by using biomass materials in polishing pads that have been manufactured using petroleum-based materials. Furthermore, there is a need to provide polishing pads that have physical properties that enable them to achieve the level of removal rate required in CMP processes even when using biomass materials. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Republic of Korea Patent Publication No. 2018-0044771 Summary of the Invention [Problem to be solved by the invention]

[0007] The realization example is to provide a polishing pad that is environmentally friendly and has physical properties that enable it to achieve the level of polishing rate required in the CMP process.

[0008] Furthermore, the present embodiment provides a method for manufacturing a polishing pad that can efficiently manufacture the polishing pad. [Means for solving the problem]

[0009] According to an embodiment for solving the above problem, a polishing pad is provided which includes a top pad layer made from a biomass-containing composition and has a total biomass content of 1% by weight to 50% by weight as measured according to the ASTM D 6866 standard.

[0010] According to another embodiment, there is provided a method for manufacturing a polishing pad having a total biomass content of 1% by weight to 50% by weight as measured according to ASTM D 6866 standard, the method including the steps of: preparing a biomass-containing urethane prepolymer from a urethane prepolymer composition including an isocyanate raw material and a polyol raw material including a biopolyol; preparing a biomass-containing composition including the biomass-containing urethane prepolymer, a curing agent, and a foaming agent; and curing the biomass-containing composition to manufacture a top pad layer. [Effects of the Invention]

[0011] The polishing pad according to the embodiment is manufactured using a composition containing biomass raw materials, and the components and content of the biomass raw materials are optimized to control the biomass content in the polishing pad within a specific range, which makes it environmentally friendly and allows it to exhibit the physical properties required in the CMP process (e.g., hardness, modulus, etc.).

[0012] Therefore, when a CMP process is performed using a polishing pad according to the embodiment, a semiconductor substrate (e.g., a wafer) exhibiting a high polishing rate and excellent surface processing quality can be provided. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a cross-sectional view of a polishing pad according to one implementation. DETAILED DESCRIPTION OF THE INVENTION

[0014] The present invention will be described below using examples. Note that the examples are not limited to the contents disclosed below, and may be modified in various forms as long as the gist of the invention is not changed.

[0015] In this specification, when a component is described as being formed above / below another component, or as being connected or coupled to each other, this includes being formed, coupled or coupled directly between these components, or indirectly via other components. It should also be understood that the reference to the above / below of each component may change depending on the direction from which the object is viewed.

[0016] As used herein, the term "comprising" is intended to embody certain features, regions, steps, steps, elements and / or components, and does not exclude the presence or addition of other features, regions, steps, steps, elements and / or components, unless specifically stated to the contrary.

[0017] All numbers and expressions expressing quantities of components, reaction conditions, and the like described herein may be understood to be modified in all instances by the term "about," unless otherwise specified.

[0018] <Polishing pad> An embodiment provides a polishing pad including a top pad layer, and optionally further including an adhesive layer and a sub-pad layer. The polishing pad according to this embodiment is manufactured using a composition containing a biomass raw material, and has the characteristic that the biomass content contained in the polishing pad is controlled within a specific range by optimizing the components and content of the biomass raw material, which will be described in detail with reference to FIG.

[0019] The term "biomass" refers to an energy source obtained from living organisms, specifically, an energy source obtained from plant and animal resources such as trees, flowers, corn, sugarcane, grass, whale oil, and birds, or organic waste resources such as livestock manure, food waste, and sawdust, and containing biocarbon (radioactive carbon (C14)).

[0020] Meanwhile, the biomass (biocarbon) content described below may refer to a value measured based on ASTM D 6866, which is a standard analytical method for measuring the biomass (biocarbon) content of a solid, liquid, or gas sample using radiocarbon dating or accelerator mass spectrometry (AMS).

[0021] The radiocarbon dating method may include the following steps. Specifically, a pre-treated (e.g., foreign material removal) sample (test piece) is placed in a special vacuum device and burned to produce carbon dioxide. Next, molten lithium is mixed with the sample to produce lithium carbide, which is then cooled and reacted with water to produce acetylene gas. The acetylene gas is then purified and converted to benzene using a silica-alumina catalyst. The 92% carbon benzene is then mixed with scintillation chemicals, and radioactivity is measured using a liquid scintillation counter for approximately two days.

[0022] The acceleration mass spectrometry method may include the following steps: Specifically, a pre-treated (e.g., foreign material removal) sample (test piece) is burned to produce purified carbon dioxide, which is then reacted with hydrogen in a special glass vacuum chamber to produce graphite. The 100% carbon graphite is then placed in an acceleration mass analyzer and its radioactivity is measured for about 30 minutes.

[0023] [Top pad layer] The top pad layer 10 included in the polishing pad 100 according to the embodiment serves to polish a semiconductor substrate (e.g., a wafer) to be polished. The top pad layer 10 is manufactured from a biomass-containing composition (composition for forming the top pad layer). Specifically, the top pad layer 10 is manufactured (formed) using a composition (A) containing a biomass raw material, and the biomass raw material may be a biomass-containing urethane prepolymer (A1).

[0024] The biomass-containing urethane prepolymer (A1) may be a prepolymer obtained by reacting a bio-containing polyol raw material with an isocyanate raw material. Specifically, the biomass-containing urethane prepolymer (A1) may be produced from a urethane prepolymer composition containing a polyol raw material (A11) containing a biopolyol and an isocyanate raw material (A12).

[0025] The bio-polyol-containing polyol raw material (A11) is derived from biomass and contains biocarbon, but is not particularly limited as long as it is a polyol raw material containing a bio-polyol having two or more hydroxyl groups (OH). Specifically, the polyol raw material (A11) may contain one or more bio-polyols selected from the group consisting of biopolymer polyols (A111) and biomonomer polyols (A112). For example, the bio-polyol may consist of the biopolymer polyol (A111) alone, the biomonomer polyol (A112) alone, or a mixture of the biopolymer polyol (A111) and the biomonomer polyol (A112).

[0026] The biopolymer polyol (A111) is derived from biomass and contains biocarbon, but is not particularly limited as long as it is a multi-molecular biopolyol having two or more hydroxyl groups (OH). Specifically, the biopolymer polyol (A111) may include one or more selected from the group consisting of biopolyether polyol, biopolyester polyol, biopolycarbonate polyol, and biopolycaprolactam polyol. When the biopolymer polyol (A111) includes the multi-molecular biopolyol, the viscosity of the urethane prepolymer composition is reduced, ensuring processability, while providing a polishing pad (100) with excellent flexibility, elastic recovery, permanent deformation rate, weather resistance, hydrolysis resistance, etc. For example, the biopolymer polyol (A111) may be ECOTRION (registered trademark) H2000 or ECOTRION H1000 from SK Chemicals; BI-550 or B-1184 from SK pucore; Sovermol (registered trademark) 1102, Sovermol 1005, Sovermol 805, or Sovermol 815 from BASF; BP-04 or BP-05 from NOROO; Priplast (registered trademark) 2033 or Priplast 1838 from Croda; Velvetol H500, Velvetol H1000, Velvetol H2000, or Velvetol H2700 from ALLESSA; or a combination thereof.

[0027] The biopolymer polyol (A111) has a weight-average molecular weight of 400 to 3000 g / mol, specifically 450 to 2700 g / mol, 500 to 2300 g / mol, 600 to 1800 g / mol, 700 to 1500 g / mol, or 800 to 1200 g / mol, and a hydroxyl value (OH-value) of 35 to 250 mgKOH / g, specifically 45 to 230 mgKOH / g, 60 to 200 mgKOH / g, 70 to 180 mgKOH / g, 80 to 150 mgKOH / g, or 90 to 130 mgKOH / g. When the weight average molecular weight and hydroxyl value of the biopolymer polyol (A111) are within the above ranges, a polishing pad 100 having excellent flexibility, elastic recovery force, permanent deformation rate, weather resistance, hydrolysis resistance, etc. can be provided.

[0028] The biopolymer polyol (A111) has a biomass content (biomass carbon content in the biopolymer polyol (A111)) of 20 to 100 wt % based on the total weight of the biopolymer polyol (A111), specifically 25 to 100 wt %, 40 to 100 wt %, 50 to 100 wt %, 60 to 100 wt %, 70 to 100 wt %, or 80 to 100 wt %. When the biomass content of the biopolymer polyol (A111) is within the above range, a polishing pad 100 can be provided that has the physical properties required for the CMP process and is environmentally friendly.

[0029] The biomonomer polyol (A112) is derived from biomass and contains biocarbon, but is not particularly limited as long as it is a monomolecular biopolyol having two or more hydroxyl groups (OH). Specifically, the biomonomer polyol (A112) may be bioethylene glycol, biodiethylene glycol, bio 1,2-propylene glycol, bio 1,3-propanediol, bio 2-methyl-1,3-propanediol, bio 1,3-butanediol, bio 1,4-butanediol, bio 2,3-butanediol, bio n-butanol, bio isobutanol, bio 1,5-pentanediol, bio 2-octanol, bio The biomonomer polyol (A112) may contain one or more selected from the group consisting of bio-1,9-nonanediol, bio-1,10-decanediol, bio-diethylene glycol, and bio-isosorbide. When the biomonomer polyol (A112) contains the monomolecular biopolyol, the crosslink density of the urethane prepolymer composition is increased, and a polishing pad 100 having excellent hardness, durability, etc. can be provided.

[0030] The biomonomer polyol (A112) has a weight-average molecular weight of 50 to 200 g / mol, specifically 55 to 180 g / mol, 60 to 150 g / mol, 65 to 130 g / mol, 70 to 100 g / mol, or 75 to 90 g / mol. When the weight-average molecular weight of the biomonomer polyol (A112) is within this range, a polishing pad 100 with excellent hardness, durability, etc. can be provided.

[0031] The biomonomer polyol (A112) may have a biomass content (biomass carbon content in the biomonomer polyol (A112)) of 100% by weight based on the total weight of the biomonomer polyol (A112). When the biomass content of the biomonomer polyol (A112) is within the above range, a polishing pad 100 having the properties required for the CMP process and excellent environmental friendliness can be provided.

[0032] The polyol raw material (A11) may further include a petroleum-based polyol in addition to the biopolyol. Specifically, the polyol raw material (A11) may include one or more selected from the group consisting of petroleum-based polymer polyols and petroleum-based monomer polyols. The petroleum-based polymer polyol may include one or more selected from the group consisting of conventionally known polyether polyols, polyester polyols, polycarbonate polyols, and polycaprolactam polyols. The petroleum-based monomer polyol may include one or more selected from the group consisting of conventionally known ethylene glycol, diethylene glycol, 1,2-propylene glycol, 1,3-propanediol, 2-methyl-1,3-propanediol, dipropylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, n-butanol, isobutanol, 1,5-pentanediol, 1,6-hexanediol, 2-octanol, 1,9-nonanediol, 1,10-decanediol, and isosorbide.

[0033] When the polyol raw material (A11) contains both the bio-polyol (a) and the petroleum-based polyol (b), the mixing ratio (a:b) thereof can be 1:0.65 to 1:3, 1:0.65 to 1:1.5, 1:0.65 to 1:1.25, 1:0.65 to 1:0.92, 1:0.68 to 1:0.90, 1:0.72 to 1:0.88, 1:0.75 to 1:0.86, or 1:0.80 to 1:0.85. By keeping the mixing ratio within the above range, it is possible to provide a polishing pad 100 that has the physical properties required for the CMP process and is environmentally friendly.

[0034] On the other hand, the isocyanate raw material (A12) is not particularly limited as long as it contains a conventionally known petroleum-based isocyanate (A121). Specifically, the isocyanate raw material (A12) may contain one or more selected from the group consisting of petroleum-based aromatic diisocyanates, petroleum-based aliphatic diisocyanates, and petroleum-based alicyclic diisocyanates. More specifically, the isocyanate raw material (A12) may contain one or more selected from the group consisting of petroleum-based aromatic diisocyanates and petroleum-based alicyclic diisocyanates.

[0035] For example, the isocyanate raw material (A12) may include one or more selected from the group consisting of toluene diisocyanate, naphthalene-1,5-diisocyanate, p-phenylene diisocyanate, tolidine diisocyanate, 4,4'-diphenylmethane diisocyanate, hexamethylene diisocyanate, 4,4'-methylenedicyclohexyl diisocyanate, and isophorone diisocyanate.

[0036] Preferably, the isocyanate raw material (A12) may contain one or more selected from the group consisting of toluene diisocyanate (TDI) and 4,4'-methylene dicyclohexyl diisocyanate (H12MDI). When the isocyanate raw material (A12) contains toluene diisocyanate (TDI), 4,4'-methylene dicyclohexyl diisocyanate (H12MDI), or a mixture thereof, a hard segment is formed, and a polishing pad 100 having the desired level of hardness can be provided. When the toluene diisocyanate (TDI) (x) and the 4,4'-methylenedicyclohexyl diisocyanate (H12MDI) (y) are used in combination, the mixing ratio (x:y) thereof is not particularly limited, but may be specifically a weight ratio of 3:1 to 20:1, a weight ratio of 5:1 to 18:1, a weight ratio of 7:1 to 16:1, or a weight ratio of 8:1 to 13:1.

[0037] Meanwhile, the isocyanate raw material (A12) may include a bioisocyanate (A122). Specifically, the isocyanate raw material (A12) may include the petroleum-based isocyanate (A121) and the bioisocyanate (A122). The bioisocyanate (A122) is derived from biomass and contains biocarbon, but is not particularly limited as long as it is a bioisocyanate having two or more isocyanate groups (NCO). Specifically, the bioisocyanate (A122) may include bio 1,5-pentamethylene diisocyanate. For example, STABiO (registered trademark) D-370N or D-376N may be used as the bioisocyanate (A122).

[0038] The bioisocyanate (A122) has an isocyanate terminal group content (NCO%) of 20% to 30% by weight, specifically 21% to 28% by weight, 22% to 26% by weight, or 23% to 25% by weight. By having the NCO% of the bioisocyanate (A122) within this range, a polishing pad 100 with excellent hardness, durability, etc. can be provided.

[0039] The bioisocyanate (A122) has a biomass content (biocarbon content in the bioisocyanate (A122)) of 50% to 100% by weight, specifically 55% to 95%, 60% to 90%, 63% to 80%, or 65% to 75% by weight, based on the total weight of the bioisocyanate (A122). When the biomass content of the bioisocyanate (A122) is within the above range, a polishing pad 100 can be provided that has the properties required for the CMP process and is environmentally friendly.

[0040] Meanwhile, when reacting the polyol raw material (A11)(z) and the isocyanate raw material (A12)(w), the reaction ratio (z:w) is not particularly limited, but considering the overall physical properties of the top pad layer 10, it may be specifically a weight ratio of 1:2 to 1:14, a weight ratio of 1:3 to 1:12, a weight ratio of 1:4 to 1:10, or a weight ratio of 1:5 to 1:8.

[0041] The ratio (M) of the number of moles of the bio-containing raw material to the total number of moles of the polyol raw material (A11) and the isocyanate raw material (A12) can be 0.11 to 0.93, 0.11 to 0.90, 0.12 to 0.85, 0.12 to 0.80, 0.13 to 0.75, 0.13 to 0.70, 0.14 to 0.65, 0.14 to 0.60, 0.15 to 0.55, 0.15 to 0.50, 0.16 to 0.45, 0.16 to 0.42, or 0.17 to 0.38. Specifically, the ratio (M) can be a value calculated using the following formula 1. When the ratio (M) is within the above range, a polishing pad 100 can be provided that has the physical properties required in the CMP process and is environmentally friendly.

[0042] [Formula 1] M=(M BP1 +M BI1 ) / (M BP1 +M P2 +M BI1 +M I2 ) In the formula 1, M BP1 is the number of moles (total number of moles) of biopolyol contained in the urethane prepolymer composition, M P2 is the number of moles (total number of moles) of the petroleum-based polyol contained in the urethane prepolymer composition, M BI1 is the number of moles (total number of moles) of bioisocyanate contained in the urethane prepolymer composition, M I2 is the number of moles (total number of moles) of petroleum-based isocyanate contained in the urethane prepolymer composition.

[0043] The biomass-containing urethane prepolymer (A1) obtained by reacting the polyol raw material (A11) with the isocyanate raw material (A12) may have a biomass (biokara) content of 4% to 80% by weight. Specifically, the biomass content of the biomass-containing urethane prepolymer (A1), based on the total weight of the biomass-containing urethane prepolymer (A1), may be 4% to 78% by weight, 7% to 76% by weight, 8% to 74% by weight, 9% to 72% by weight, 10% to 69% by weight, 25% to 67% by weight, or 45% to 65% by weight. By ensuring that the biomass content of the biomass-containing urethane prepolymer (A1) is within the above range, a polishing pad 100 can be provided that has the physical properties required for the CMP process and is environmentally friendly.

[0044] The biomass-containing urethane prepolymer (A1) has a weight-average molecular weight of 500 to 1500 g / mol, specifically 600 to 1400 g / mol, 700 to 1300 g / mol, or 800 to 1200 g / mol. The biomass-containing urethane prepolymer (A1) also has an isocyanate terminal group content (NCO%) of 6 to 14 wt%, specifically 6.5 to 13 wt%, 7 to 12 wt%, 7.5 to 11 wt%, or 8 to 10 wt%. By ensuring that the weight-average molecular weight and NCO% of the biomass-containing urethane prepolymer (A1) are within the above ranges, a polishing pad 100 with excellent removal rate in the CMP process can be provided.

[0045] On the other hand, the composition (A) containing the biomass-containing urethane prepolymer (A1) for forming the top pad layer 10 may further contain a curing agent (A2) and a foaming agent (A3).

[0046] The curing agent (A2) may include a compound that undergoes a curing reaction with the biomass-containing urethane prepolymer (A1). Specifically, the curing agent (A2) may include one or more selected from the group consisting of aromatic amines, aliphatic amines, aromatic alcohols, and aliphatic alcohols. More specifically, the curing agent (A2) may include 4,4'-methylenebis(2-chloroaniline), diethyltoluenediamine, diaminodiphenylmethane, dimethylthiotoluenediamine, propanediolbis(p-aminobenzoic acid), or the like. p-aminobenzoate, diaminodiphenylsulfone, m-xylylenediamine, isophoronediamine, ethylenediamine, diethylenetriamine, triethylenetetramine, polypropylenediamine, polypropylenetriamine, and bis(4-amino-3-chlorophenyl)methane.

[0047] The content of the curing agent (A2) is 15 to 55 parts by weight, specifically 20 to 50 parts by weight, 25 to 45 parts by weight, or 30 to 40 parts by weight, per 100 parts by weight of the biomass-containing urethane prepolymer (A1). By having the content of the curing agent (A2) within this range, it can be more advantageous to realize a polishing pad 100 with excellent physical properties.

[0048] Meanwhile, the reaction ratio (curing reaction ratio) between the biomass-containing urethane prepolymer (A1) and the curing agent (A2) is not particularly limited, but may be, for example, an equivalent ratio of 1:0.5 to 1:1.3, an equivalent ratio of 1:0.6 to 1:1.2, an equivalent ratio of 1:0.7 to 1:1.1, or an equivalent ratio of 1:0.8 to 1:1. By carrying out the curing reaction at this reaction ratio, the curing reaction is optimized, and a polishing pad 100 having the physical properties (hardness, modulus, etc.) required for the CMP process can be provided.

[0049] The foaming agent (A3) is used to form a pore structure in the top pad layer 10 and may include one or more foaming agents selected from the group consisting of solid-phase foaming agents, liquid-phase foaming agents, and gas-phase foaming agents (e.g., gases such as nitrogen, argon, helium, and carbon dioxide). Specifically, the foaming agent (A3) is preferably a solid-phase foaming agent containing expandable particles.

[0050] The expandable particles are particles that can expand due to heat or pressure, and their size in the final top pad layer can be determined by the heat or pressure applied during the manufacturing process of the top pad layer 10. Specifically, the expandable particles may include thermally expanded particles, unexpanded particles, or a combination thereof. The thermally expanded particles are particles that have been pre-expanded by heat, and may refer to particles that expand by the heat or pressure applied during the manufacturing process of the top pad layer 10 to determine their final size. Such expandable particles may include an outer shell made of a resin material and an expansion-inducing component present inside and encapsulated by the outer shell.

[0051] The resin outer shell may include a thermoplastic resin, which may be at least one selected from the group consisting of vinylidene chloride copolymers, acrylonitrile copolymers, methacrylonitrile copolymers, and acrylic copolymers.

[0052] The expansion-inducing component may include one or more selected from the group consisting of hydrocarbon compounds, chlorofluoro compounds, and tetraalkylsilane compounds.

[0053] Specifically, the hydrocarbon compound may include one or more selected from the group consisting of ethane, ethylene, propane, propene, n-butane, isobutene, n-butene, isobutene, n-pentane, isopentane, neopentane, n-hexane, heptane, and petroleum ether.

[0054] The chlorofluoro compound may include one or more selected from the group consisting of trichlorofluoromethane (CClF), dichlorodifluoromethane (CClF), chlorotrifluoromethane (CClF), and dichlorotetrafluoroethane (CClF).

[0055] The tetraalkylsilane compound may include one or more selected from the group consisting of tetramethylsilane, trimethylethylsilane, trimethylisopropylsilane, and trimethyl-n-propylsilane.

[0056] The solid-phase blowing agent has an average particle size of 5 μm to 200 μm, specifically 10 μm to 100 μm, 15 μm to 70 μm, or 20 μm to 45 μm. When the solid-phase blowing agent is the expandable particles and includes the thermally expanded particles, the average particle size may refer to the average particle size of the thermally expanded particles themselves. When the solid-phase blowing agent is the swellable particles and includes the unexpanded particles, the average particle size may refer to the average particle size of the particles after expansion by heat or pressure.

[0057] The content of the solid-phase blowing agent is 0.5 to 10 parts by weight, specifically 0.7 to 8 parts by weight, 0.9 to 6 parts by weight, or 1 to 5 parts by weight, per 100 parts by weight of the biomass-containing urethane prepolymer (A1). By having the content of the solid-phase blowing agent within this range, it can be more advantageous in realizing a polishing pad with excellent physical properties.

[0058] In addition, the composition (A) containing the biomass-containing urethane prepolymer (A1) for forming the top pad layer 10 may further contain additives such as a surfactant and a reaction rate modifier.

[0059] The surfactant is not particularly limited, but specifically may be a silicone surfactant.

[0060] The reaction rate regulator is not particularly limited, and may specifically include one or more selected from the group consisting of triethylenediamine, dimethylethanolamine, tetramethylbutanediamine, 2-methyl-triethylenediamine, dimethylcyclohexylamine, triethylamine, triisopropanolamine, 1,4-diazabicyclo[2,2,2]octane, bis(2-methylaminoethyl)ether, trimethylaminoethylethanolamine, N,N,N,N,N″-pentamethyldiethyldimethylaminoethylamine, dimethylaminopropylamine, benzyldimethylamine, n-ethylmorpholine, N,N-dimethylaminoethylmorpholine, N,N-dimethylcyclohexylamine, 2-methyl-2-azanorbornene, dibutyltin dilaurate, stannous octoate, dibutyltin diacetate, dioctyltin diacetate, dibutyltin maleate, dibutyltin bis(2-ethylhexanoate), and dibutyltin dimercaptide.

[0061] The top pad layer 10 manufactured from the composition (A) containing the biomass-containing urethane prepolymer (A1) may have a biomass (biokara) content of 2% to 70% by weight. Specifically, the biomass content of the top pad layer 10, based on the total weight of the top pad layer 10, may be 3% to 65% by weight, 5% to 60% by weight, 6% to 58% by weight, 7% to 56% by weight, 8% to 54% by weight, 20% to 52% by weight, or 35% to 50% by weight. By having the biomass content of the top pad layer 10 within this range, a polishing pad 100 can be provided that has the physical properties required for the CMP process and is environmentally friendly.

[0062] The thickness of the top pad layer 10 is not particularly limited, but may be 0.5 to 5 mm, 0.8 to 4 mm, 1 to 3 mm, or 1.5 to 2.5 mm. The hardness (Shore D) of the top pad layer 10 is not particularly limited, but may be 45 to 70, 50 to 68, 53 to 65, or 56 to 60. The average pore size formed in the top pad layer 10 is not particularly limited, but may be 10 to 40 μm, 15 to 35 μm, 18 to 30 μm, or 20 to 25 μm. When the thickness, hardness, and average pore size of the top pad layer 10 are within the above ranges, the CMP process can be performed stably, and the polishing pad 100 can be made lighter.

[0063] [Adhesive layer] The adhesive layer 20 further included in the polishing pad 100 according to the embodiment is provided between the top pad layer 10 and the subpad layer 30 and serves to bond the top pad layer 10 and the subpad layer 30. Furthermore, the adhesive layer 20 may also serve to prevent polishing slurry supplied to the top pad layer 10 from flowing out to the subpad layer 30. Such an adhesive layer 20 may be manufactured (formed) using a hot melt adhesive composition.

[0064] The hot melt adhesive composition may contain a conventionally known hot melt adhesive, specifically, the hot melt adhesive may contain one or more types selected from the group consisting of polyurethane resins, polyester resins, ethylene-vinyl acetate resins, polyamide resins, and polyolefin resins.

[0065] The thickness of the adhesive layer 20 is not particularly limited, but may be specifically 5 to 30 μm, 10 to 30 μm, 20 to 27 μm, or 23 to 25 μm. When the thickness of the adhesive layer 20 is within the above range, the bonding strength (adhesion strength) between the top pad layer 10 and the subpad layer 30 can be ensured at a required level.

[0066] [Subpad layer] The subpad layer 30 further included in the polishing pad according to the embodiment is provided under the top pad layer 10 and serves to stably support the top pad layer 10 while absorbing and / or dispersing impacts applied to the top pad layer 10. The subpad layer 30 may be manufactured (formed) using a nonwoven fabric, suede, or a porous pad.

[0067] The thickness of the subpad layer 30 is not particularly limited, but may be 0.5 mm to 4 mm, 0.6 mm to 3.5 mm, 0.8 mm to 3 mm, or 1 mm to 2 mm. The hardness (Asker C) of the subpad layer 30 is not particularly limited, but may be 55 to 90, 60 to 85, 65 to 80, or 70 to 75. When the thickness and hardness of the subpad layer 30 are within the above ranges, the polishing pad can be made lighter while stably supporting the top pad layer 10.

[0068] The polishing pad 100 according to this embodiment may be environmentally friendly because the top pad layer 10 is made from a biomass-containing composition. Furthermore, the polishing pad 100 according to this embodiment has optimally controlled compositions and contents of the polymer raw material and the isocyanate raw material contained in the biomass-containing composition used to manufacture the top pad layer 10, and contains a biomass content within a specific range. As a result, the polishing pad 100 has the physical properties required for the CMP process and may have excellent polishing rates, cutting rates, etc.

[0069] Specifically, the polishing pad 100 according to the embodiment may have a biomass (biokara) content of 1% to 50% by weight based on the total weight of the polishing pad 100. More specifically, the total biomass content of the polishing pad 100 based on the total weight of the polishing pad 100 may be 2% to 50% by weight, 3% to 50% by weight, 4% to 50% by weight, 5% to 50% by weight, 6% to 50% by weight, 7% to 50% by weight, 8% to 50% by weight, 2% to 45% by weight, 3% to 42% by weight, 4% to 38% by weight, 4.5% to 36% by weight, 5% to 34% by weight, 8% to 32% by weight, 15% to 33% by weight, or 25% to 32% by weight. When the biomass content of the polishing pad 100 is within the above range, it is possible to provide a polishing pad 100 that is excellent in polishing rate, cutting rate, etc. in the CMP process and is also very environmentally friendly.

[0070] Meanwhile, the polishing pad 100 according to the embodiment may have a compressibility (%) of 0.3% to 1.8%, 0.4% to 1.6%, 0.5% to 1.5%, 0.6% to 1.4%, or 0.8% to 1.3%.

[0071] Furthermore, the polishing pad 100 according to the embodiment may have a CMP process polishing rate (Å / min) of 1900 to 4200 Å / min, 2500 to 4150 Å / min, 3000 to 4100 Å / min, 3500 to 4050 Å / min, or 4000 to 4040 Å / min.

[0072] Additionally, the polishing pad 100 according to the embodiment may have a polishing pad removal rate (μm / hr) of 31 to 42 μm / hr, 31.5 to 41 μm / hr, 33 to 40.5 μm / hr, 35 to 40 μm / hr, or 38 to 39.5 μm / hr.

[0073] <Polishing Pad Manufacturing Method> The present embodiment provides a method for manufacturing a polishing pad that can efficiently produce the polishing pad described above. Specifically, the method for manufacturing a polishing pad according to the present embodiment includes the steps of: preparing a biomass-containing urethane prepolymer from a urethane prepolymer composition containing an isocyanate raw material and a polyol raw material containing a biopolyol; preparing a biomass-containing composition containing the biomass-containing urethane prepolymer, a curing agent, and a foaming agent; and curing the biomass-containing composition to produce a top pad layer. The total biomass content, as measured according to ASTM D 6866, can be 1% by weight to 50% by weight.

[0074] Specifically, the step of preparing the biomass-containing urethane prepolymer may involve introducing a urethane prepolymer composition containing the polyol raw material and the isocyanate raw material into a reactor and reacting them. The reaction conditions are not particularly limited, but the reaction temperature may be 70°C to 90°C (specifically 75°C to 85°C), and the reaction time may be 1 hour to 4 hours (specifically 2 hours to 3 hours). The explanations for the polyol raw material and the isocyanate raw material are the same as those for the polyol raw material (A11) and the isocyanate raw material (A12), and therefore will be omitted.

[0075] The step of preparing the biomass-containing composition may include a process of charging the biomass-containing urethane prepolymer, curing agent, and blowing agent into respective injection lines and mixing them. The mixing may be performed at a speed of 1,000 to 10,000 rpm, 2,500 to 8,500 rpm, or 4,000 to 7,000 rpm. The blowing agent may be mixed through an injection line separate from the biomass-containing urethane prepolymer injection line, or may be premixed with the biomass-containing urethane prepolymer before the biomass-containing urethane prepolymer is charged into the injection line. The description of the biomass-containing urethane prepolymer, curing agent, and blowing agent is omitted here because they are the same as those of the biomass-containing urethane prepolymer (A1), curing agent (A2), and blowing agent (A3) described above.

[0076] The step of preparing the top pad layer may include a process of introducing the biomass-containing composition into a mold and curing the composition. The curing reaction conditions are not particularly limited, but the curing reaction temperature is 60°C to 130°C (specifically, 75°C to 100°C), and the mold pressure is 50 to 260 kg / m. 2 (Specifically, 80 to 180 kg / m 2 ) can be.

[0077] The method for manufacturing a polishing pad according to an embodiment may further include a step of manufacturing an adhesive layer and a subpad layer after manufacturing the top pad layer, and may further include a step of cutting the surface of the top pad layer, a step of processing grooves in the surface of the top pad layer, a polishing pad inspection step, or a polishing pad packaging step, and these steps may be performed using conventional methods for manufacturing polishing pads.

[0078] (Example) The present embodiment will be described in more detail below with reference to examples, but the scope of the present embodiment is not limited to these examples.

[0079] Example 1 [Example 1-1: Production of biomass-containing urethane prepolymer] 165g of toluene diisocyanate (TDI) and 25g of 4,4'-methylenedicyclohexyl diisocyanate (H12MDI) were used as isocyanate raw materials, and 285g of biopolymer polyol (ECOTRION H1000, SK Chemicals (molecular weight 1000g / mol, hydroxyl value (OH) 102.0-124.7, biomass content 100% by weight based on the total weight of the biopolymer polyol)) and 25g of diethylene glycol were added to a four-neck flask and reacted at 80°C for 3 hours to produce a biomass-containing urethane prepolymer with an NCO% of 9%.

[0080] [Example 1-2: Top pad layer manufacturing] In a casting machine equipped with an inert gas injection line, the biomass-containing urethane prepolymer prepared in Example 1-1 was filled into a prepolymer tank, bis(4-amino-3-chlorophenyl)methane (Ishihara Chemical Co., Ltd.) was filled into a curing agent tank, and nitrogen (N2) was used as the inert gas. Meanwhile, 1 part by weight of a solid-phase blowing agent (Akzonobel Co., Ltd.) and 1 part by weight of a silicone surfactant (Evonik Co., Ltd.) were added to 100 parts by weight of the urethane prepolymer through separate lines and mixed with the urethane prepolymer.

[0081] Each raw material was mixed into a mixing head at a constant rate through its respective feed line. The urethane prepolymer and the curing agent were mixed at a 1:1 equivalence ratio, and nitrogen (N2), an inert gas, was injected at a rate of 0.5 to 1.5 L / min. The mixed raw material was discharged into a mold (1000 mm x 1000 mm x 3 mm) preheated to 80°C at a rate of 10 kg / min and then cast to obtain a molded body. The top and bottom of the molded body were then cut to a thickness of 0.5 mm each to obtain a 2 mm-thick top pad (top pad layer) (specific gravity 0.82 g / cc, average pore size 23.6 μm).

[0082] [Example 1-3: Polishing pad production] A subpad (thickness: 1.1 mm) was prepared by impregnating a polyester fiber nonwoven fabric with polyurethane resin. The top pad prepared in Example 1-2 was then bonded to the subpad using a hot melt adhesive to prepare a polishing pad (thickness: 3.32 mm) having a top pad layer / adhesive layer / subpad layer structure.

[0083] Example 2 [Example 2-1: Production of biomass-containing urethane prepolymer] 180 g of toluene diisocyanate (TDI) and 25 g of 4,4'-methylenedicyclohexyl diisocyanate (H12MDI) were used as isocyanate raw materials, and 265 g of biopolymer polyol (ECOTRION H1000, SK Chemicals (molecular weight 1000 g / mol, hydroxyl value 102.0-124.7, biomass content 100 wt.% based on the total weight of biopolymer polyol) and 25 g of bio-1,3-propanediol (molecular weight 76 g / mol, biomass content 100 wt.% based on the total weight of bio-1,3-propanediol) were added to a four-neck flask and reacted at 80°C for 3 hours to produce a biomass-containing urethane prepolymer with an NCO content of 9%.

[0084] [Example 2-2: Top pad layer manufacturing] A top pad (top pad layer) (specific gravity 0.81 g / cc, average pore size 23.1 μm) was prepared in the same manner as in Example 1-2, except that the urethane prepolymer prepared in Example 2-1 was used instead of the urethane prepolymer prepared in Example 1-1.

[0085] [Example 2-3: Polishing pad production] A polishing pad (thickness: 3.32 mm) having a top pad layer / adhesive layer / subpad layer structure was prepared by the same process as in Example 1-3, except that the top pad prepared in Example 2-2 was used instead of the top pad prepared in Example 1-2.

[0086] Example 3 [Example 3-1: Production of biomass-containing urethane prepolymer] 175 g of toluene diisocyanate (TDI) and 25 g of 4,4'-methylenedicyclohexyl diisocyanate (H12MDI) were added as isocyanate raw materials, and 260 g of polytetramethylene ether glycol and 25 g of bio-1,3-propanediol (molecular weight 76 g / mol, biomass content 100 wt% based on the total weight of bio-1,3-propanediol) were added as polyol raw materials to a four-neck flask and reacted at 80°C for 3 hours to produce a biomass-containing urethane prepolymer with an NCO content of 9%.

[0087] [Example 3-2: Top pad layer manufacturing] A top pad (top pad layer) (specific gravity 0.82 g / cc, average pore size 23.4 μm) was prepared in the same manner as in Example 1-2, except that the urethane prepolymer prepared in Example 3-1 was used instead of the urethane prepolymer prepared in Example 1-1.

[0088] [Example 3-3: Production of polishing pad] A polishing pad (thickness: 3.32 mm) having a top pad layer / adhesive layer / subpad layer structure was prepared by the same process as in Example 1-3, except that the top pad prepared in Example 3-2 was used instead of the top pad prepared in Example 1-2.

[0089] (Comparative Example 1) [Comparative Example 1-1: Production of biomass-containing urethane prepolymer] 30 g of 4,4'-methylenedicyclohexyl diisocyanate (H12MDI) and 365 g of bioisocyanate (STABiOD-376N, Mitsui Chemicals, Inc. (molecular weight 350 g / mol, biomass content 67 wt.% based on the total weight of bioisocyanate)) were added as isocyanate raw materials, and 60 g of biopolymer polyol (ECOTRION H1000, SK Chemicals, Inc. (molecular weight 1000 g / mol, hydroxyl value 102.0-124.7, biomass content 100 wt.% based on the total weight of biopolymer polyol) and 45 g of bio-1,3-propanediol (molecular weight 76 g / mol, biomass content 100 wt.% based on the total weight of bio-1,3-propanediol) were added as polyol raw materials to a four-neck flask and reacted at 80 °C for 3 hours to produce a biomass-containing urethane prepolymer with an NCO content of 9%.

[0090] [Comparative Example 1-2: Top Pad Layer Manufacturing] A top pad (top pad layer) (specific gravity 0.81 g / cc, average pore size 23.1 μm) was prepared in the same manner as in Example 1-2, except that the urethane prepolymer prepared in Comparative Example 1-1 was used instead of the urethane prepolymer prepared in Example 1-1.

[0091] [Comparative Example 1-3: Polishing Pad Manufacturing] A polishing pad (thickness: 3.32 mm) having a top pad layer / adhesive layer / subpad layer structure was prepared by the same process as in Example 1-3, except that the top pad prepared in Comparative Example 1-2 was used instead of the top pad prepared in Example 1-2.

[0092] (Comparative Example 2) [Comparative Example 2-1: Production of biomass-containing urethane prepolymer] 140 g of toluene diisocyanate (TDI) and 20 g of 4,4'-methylenedicyclohexyl diisocyanate (H12MDI) were charged into a four-neck flask as isocyanate raw materials, and 340 g of polytetramethylene ether polyol (Polytetramethylene ether glycol) was added as a polyol raw material. The mixture was then reacted at 80°C for 3 hours to produce a biomass-free urethane prepolymer with an NCO% of 9%.

[0093] [Comparative Example 2-2: Top Pad Layer Manufacturing] A top pad (top pad layer) (specific gravity 0.81 g / cc, average pore size 22.2 μm) was prepared in the same manner as in Example 1-2, except that the urethane prepolymer prepared in Comparative Example 2-1 was used instead of the urethane prepolymer prepared in Example 1-1.

[0094] [Comparative Example 2-3: Polishing Pad Manufacturing] A polishing pad (thickness: 3.32 mm) having a top pad layer / adhesive layer / subpad layer structure was prepared by the same process as in Example 1-3, except that the top pad prepared in Comparative Example 2-2 was used instead of the top pad prepared in Example 1-2.

[0095] (Test Example 1: Biomass Content Analysis) Based on the ASTM D 6866 standard (radiocarbon dating method applied), the biomass (biocarbon) content (sample size: 5 cm length x 5 cm width) contained in the urethane prepolymer, top pad layer, and polishing pad was analyzed, and the results are shown in Table 1 below.

[0096] JPEG0007810740000001.jpg49165

[0097] Referring to Table 1, it can be seen that Examples 1 to 3, which are polishing pads according to the present invention, have a biomass content that satisfies the ranges of 1 wt% to 50 wt% based on the total weight of the polishing pad, 2 wt% to 70 wt% based on the total weight of the top pad layer, and 4 wt% to 80 wt% based on the total weight of the urethane prepolymer, while Comparative Examples 1 and 2 do not have a biomass content that satisfies these ranges.

[0098] (Test Example 2: Physical Property Evaluation) The physical properties of the top pads, subpads, and polishing pads produced in Examples 1 to 3 and Comparative Examples 1 and 2 were evaluated as follows, and the results are shown in Table 2 below.

[0099] 1.Hardness The top pad (thickness: 2 mm, length: 5 cm, width: 5 cm) and the sub-pad (thickness: 1.1 mm, length: 5 cm, width: 5 cm) were each stored at 25°C for 12 hours, and then the Shore D hardness and Asker C hardness were measured using a hardness tester.

[0100] 2. Tensile strength The maximum strength value just before breakage was measured for the top pad (thickness: 2 mm, length: 1 cm, width: 4 cm) using a universal testing meter (UTM) at a speed of 50 mm / min.

[0101] 3. Growth rate The maximum deformation length just before breakage was measured for the top pad (thickness: 2 mm, length: 1 cm, width: 4 cm) using a universal testing meter (UTM) at a speed of 50 mm / min, and the elongation was then measured by calculating the ratio (percentage (%)) of the maximum deformation length to the initial length.

[0102] 4. Compression ratio Using a dial thickness gauge (YASUDA, 129-E) for a polishing pad (thickness: 3.32 mm, length: 25 mm, width: 25 mm), an 85 g weight was placed on the pad for 30 seconds, and the measured thickness (A) was measured. An additional 800 g weight (85 g weight + 800 g weight) was placed on the pad for 3 minutes, and the change in the measured thickness (B) was calculated to measure the compressibility ((AB) / A*100).

[0103] 5. Polishing rate A polishing pad was fixed on the platen of a CMP apparatus, and a silicon wafer (diameter: 300 mm) was placed with the silicon oxide film facing down to perform the CMP process. Specifically, the polishing load was adjusted to 4.0 psi, and calcined silica slurry was added to the polishing pad at a rate of 250 ml / min while the platen was rotated at 150 rpm for 60 seconds to polish the silicon oxide film. After polishing, the silicon wafer was removed from the carrier, attached to a spin dryer, washed with purified water, and then dried with nitrogen for 15 seconds. The difference in thickness of the dried silicon wafer before and after polishing was measured using a spectroscopic interference thickness meter (Kyence, SI-F80R), and the polishing rate was calculated according to the following equation 2. [Formula 2] Polishing rate (Å / min) = Polished thickness of silicon wafer (silicon oxide film) (Å) / Polishing time (min)

[0104] 6. Polishing pad cutting rate The polishing pad was first preconditioned with deionized water for 10 minutes, then conditioned again by spraying deionized water for 1 hour, and the change in polishing pad thickness was measured. Conditioning was performed using a CTS AP-300HM device with a conditioning pressure of 6 lbf and a rotation speed of 100-110 rpm. The disk used for conditioning was a Sasol LPX-DS2.

[0105] JPEG0007810740000002.jpg77165

[0106] Referring to Table 2, it can be seen that the polishing pads of Examples 1 to 3, in which the total biomass content was controlled within the range of the Realized Examples, exhibited excellent overall physical properties, whereas the polishing pad of Comparative Example 1, which was outside the range of the Realized Examples, exhibited significantly reduced physical properties. It can also be seen that the polishing pads of Examples 1 to 3, although manufactured using biopolyol raw materials, exhibited physical properties equivalent to or superior to those of the polishing pad of Comparative Example 2, which was manufactured using petroleum-based polyol raw materials. This demonstrates that the Realized Examples can provide polishing pads that are both excellent in physical properties and environmentally friendly. [Explanation of symbols]

[0107] 100: Polishing pad 10: Top pad layer 20: Adhesive layer 30: Sub-pad layer

Claims

1. a top pad layer made from a biomass-containing composition; The total biomass content measured according to ASTM D 6866 standard is 1% by weight to 50% by weight; The biomass content of the top pad layer is 2 wt% to 70 wt% based on the total weight of the top pad layer; A polishing pad, wherein the hardness of the top pad layer is 50 Shore D to 68 Shore D.

2. the biomass-containing composition comprises a biomass-containing urethane prepolymer; 2. The polishing pad according to claim 1, wherein the biomass-containing urethane prepolymer is produced from a urethane prepolymer composition containing an isocyanate raw material and a polyol raw material containing a biopolyol.

3. 3. The polishing pad of claim 2, wherein the biomass content of the biomass-containing urethane prepolymer is 4% by weight to 80% by weight based on the total weight of the biomass-containing urethane prepolymer.

4. The polishing pad of claim 2 , wherein the biopolyol comprises at least one selected from the group consisting of biopolymer polyols and biomonomer polyols.

5. 5. The polishing pad of claim 4, wherein the biopolymer polyol comprises one or more selected from the group consisting of biopolyether polyol, biopolyester polyol, biopolycarbonate polyol, and biopolycaprolactam polyol.

6. The polishing pad according to claim 4, wherein the biomonomer polyol comprises one or more selected from the group consisting of bioethylene glycol, biodiethylene glycol, bio-1,2-propylene glycol, bio-1,3-propanediol, bio-2-methyl-1,3-propanediol, bio-1,3-butanediol, bio-1,4-butanediol, bio-2,3-butanediol, bio-n-butanol, bioisobutanol, bio-1,5-pentanediol, bio-2-octanol, bio-1,9-nonanediol, bio-1,10-decanediol, biodiethylene glycol, and bioisosorbide.

7. 3. The polishing pad of claim 2, wherein the isocyanate raw material comprises one or more selected from the group consisting of toluene diisocyanate (TDI) and 4,4'-methylenedicyclohexyl diisocyanate (H12MDI).

8. The polishing pad of claim 2 , wherein the isocyanate raw material comprises a bioisocyanate.

9. A step of producing a biomass-containing urethane prepolymer from a urethane prepolymer composition including an isocyanate raw material and a polyol raw material including a bio-polyol; providing a biomass-containing composition comprising the biomass-containing urethane prepolymer, a curing agent, and a foaming agent; and curing the biomass-containing composition to produce a top pad layer; The total biomass content measured according to ASTM D 6866 standard is 1% by weight to 50% by weight; The biomass content of the top pad layer is 2 wt% to 70 wt% based on the total weight of the top pad layer; The method for manufacturing a polishing pad, wherein the hardness of the top pad layer is 50 Shore D to 68 Shore D.

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