Polishing pad and polishing method

Abstract

A polishing pad having a polishing layer with a polishing surface, wherein the polishing layer comprises a reaction product of an isocyanate-terminated prepolymer in combination with a curative composition, wherein the curative composition comprises a polyamine and a polyether polyol having a kinematic viscosity at 40°C between 130 cSt and 1100 cSt and a ratio of kinematic viscosity at 40°C to kinematic viscosity at 25°C between 0.1 and 0.7; by controlling the kinematic viscosity of the polyether polyol in the curative composition at a temperature and the ratio of the kinematic viscosity at different temperatures, a polishing pad having a higher polishing rate, lower defects, and lower polishing rate non-uniformity is produced.

Description

Technical Field

[0001] This invention relates to the field of polishing technology for chemical mechanical planarization, and more specifically, to a polishing pad and a method for manufacturing semiconductor devices. Background Technology

[0002] CMP (Continuous Polishing) technology involves placing the workpiece surface downwards and applying pressure to a polishing pad. Under the action of the polishing fluid, and with the relative movement between the polishing pad and the workpiece, the material on the surface of the workpiece is removed through the mechanical grinding of the abrasive particles and the chemical corrosion of the oxidant, thereby obtaining a flat surface.

[0003] With the development of the semiconductor industry, the trend in processing technology is shifting towards higher current densities, higher clock frequencies, and more interconnect layers. Due to the shrinking size of the chips and the reduction in the depth of focus of lithography equipment, the required flatness of the chip surface to achieve a resolution at the nanometer level is necessary. Traditional planarization techniques, such as selective deposition based on deposition technology, SOG sputtering, low-pressure CVD, and plasma-enhanced CVD, can also provide smooth surfaces, but these are all local planarization techniques and cannot achieve global planarization. Currently, it is generally accepted internationally that when the feature size of a device is below 0.35μm, global planarization must be performed to ensure the accuracy and resolution of lithographic influence transfer. CMP technology is currently the only internationally recognized technology that can achieve global planarization, and CMP yield significantly affects chip yield.

[0004] The sharp increase in market demand for chips has led to a chip shortage in the past two years. Although advanced process chips such as 5nm and 3nm have become known to the public through products such as mobile phones, the market is still dominated by mature processes. Although mature processes have relatively low requirements for CMP consumables, they place extremely stringent requirements on CMP consumables, especially polishing pads, for removal rate, defects, and grinding rate instability. Therefore, there is an urgent need to develop a product that is more suitable for mature processes. Summary of the Invention

[0005] To address the problems in the prior art, the first aspect of the present invention provides a polishing pad having a polishing layer with a polishing surface, the polishing layer comprising a reaction product of the following components: an isocyanate-terminated prepolymer and a curing agent composition; the curing agent composition comprising a polyamine and a polyether polyol, wherein the kinematic viscosity of the polyether polyol at 40°C is between 130 cSt and 1100 cSt, and the ratio of the kinematic viscosity of the polyether polyol at 40°C to its kinematic viscosity at 25°C is between 0.1 and 0.7;

[0006] Furthermore, the structure of the polyether polyol is shown in Chemical Formula 1:

[0007]

[0008] In the polyether polyol represented by chemical formula 1, z is between 3 and 8, R represents a trivalent to octvalent organic group, M represents a divalent organic group, and P represents a monovalent organic group;

[0009] Preferably, in chemical formula 1, M represents a structural segment formed by homopolymerization and / or copolymerization of structural units as shown in structural formula 2 and / or structural formula 3, wherein "*" represents a bonding site:

[0010]

[0011] Furthermore, the molar quantity of the structural unit shown in structural formula 2 is x, and the molar quantity of the structural unit shown in structural formula 3 is y, wherein x / y is between 0.03 and 1;

[0012] Preferably, x / y is between 0.03 and 0.5; particularly preferably, x / y is between 0.08 and 0.3.

[0013] Furthermore, in the polyether polyol chemical formula 1, P represents a hydrogen atom or a structural unit as shown in structural formula 4;

[0014] Preferably, in the polyether polyol of formula 1, P represents a structural unit as shown in structural formula 4:

[0015]

[0016] Furthermore, in the polyether polyol chemical formula 1, R represents one or more combinations of structural units as shown in structural formula 5-1, where "*" represents a bonding site:

[0017]

[0018] Preferably, in the polyether polyol chemical formula 1, R represents one or more combinations of structural units as shown in structural formulas 5-2, where "*" represents a bonding site:

[0019]

[0020] Furthermore, the curing agent composition comprises one or more of the following polyamines: diethyltoluenediamine (DETDA), 4,4'-methylene-bis-(2-chloroaniline) (MOCA), and 4,4'-methylene-bis-(3-chloro-2,6-diethylaniline) (MCDEA);

[0021] Furthermore, the ratio of the kinematic viscosity of the polyether polyol at 80°C to its kinematic viscosity at 60°C is between 0.6 and 0.7.

[0022] Furthermore, the molecular weight Mw of the polyether polyol is between 7000 and 12000;

[0023] Preferably, the molecular weight (Mw) of the polyether polyol is between 9500 and 12000;

[0024] Furthermore, the kinematic viscosity of the polyether polyol at 40°C is between 600 cSt and 880 cSt, and the ratio of the kinematic viscosity of the polyether polyol at 40°C to its kinematic viscosity at 25°C is between 0.43 and 0.52; furthermore, the curing agent composition has a plurality of reactive hydrogen groups, the isocyanate-terminated prepolymer has a plurality of unreacted NCO groups, the isocyanate-terminated prepolymer contains 8.95 wt% to 9.25 wt% of unreacted NCO groups, and the stoichiometric ratio of the reactive hydrogen groups to the unreacted NCO groups is between 0.87 and 1.05;

[0025] Furthermore, the density of the polished layer is between 0.7 g / cm³. 3 ~0.9g / cm 3 The hardness of the polished layer is between 50D and 63D.

[0026] A second aspect of the present invention is a polishing method, characterized in that a substrate is provided, the substrate being selected from at least one of a magnetic substrate, an optical substrate, or a semiconductor substrate; a polishing pad is provided, forming a dynamic contact between the polishing surface of the polishing layer and the substrate, thereby polishing the surface of the substrate; and an abrasive dresser is used to dress the polished surface.

[0027] Beneficial effects

[0028] This invention utilizes a curing system designed for the polishing layer material in a polishing pad. By controlling the kinematic viscosity of the polyether polyol and its variation at different temperatures, the polishing performance is improved. When the kinematic viscosity of the polyether polyol is controlled within a certain range at 40°C, the polyether polyol exhibits more suitable fluidity during the curing reaction of the polishing layer, resulting in a polishing layer with a lower defect rate. Furthermore, by controlling the ratio of the kinematic viscosity of the polyether polyol at 40°C to that at 25°C, the sensitivity of the polyether polyol's kinematic viscosity to temperature is modulated. Polishing pads prepared by controlling the kinematic viscosity within a certain range exhibit higher grinding rates and lower grinding rate inhomogeneity. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram illustrating the polishing process of the polishing pad in an embodiment of the present invention.

[0031] Figure 2 A schematic diagram of a polishing pad provided for an embodiment of the present invention;

[0032] 1-Material to be polished; 2-Polishing pad; 3-Polishing machine; 4-Support; 5-Polishing liquid; 20-Polishing layer; 21-Adhesive layer; 22-Buffer layer; 23-Backing adhesive layer. Detailed Implementation

[0033] The present invention will now be described in detail.

[0034] Polishing Pad

[0035] The polishing pad in this invention is as follows Figure 2 As shown, the polishing pad includes a polishing layer 20, a buffer layer 22, an adhesive layer 21, and a backing adhesive layer 23. The polishing pad in this invention is arranged from top to bottom as a polishing layer 20, an adhesive layer 21, a buffer layer 22, and a backing adhesive layer 23. The adhesive layer 21 is used to bond the polishing layer 20 and the buffer layer 22. The backing adhesive layer 23 also includes a release film or release paper. When in use, the release film or release paper can be peeled off to achieve bonding between the polishing pad and the polishing machine.

[0036] Polishing layer

[0037] The polishing pad of the present invention comprises a polishing layer, wherein the polishing layer comprises a reaction product including an isocyanate-terminated prepolymer and a curing agent composition.

[0038] Curing agent composition

[0039] The curing agent composition of this invention contains a polyether polyol, wherein the kinematic viscosity of the polyether polyol at 40°C is between 130 cSt and 1100 cSt. The polyether polyol in this invention has more suitable fluidity during the curing process of the polishing layer, and the prepared polishing layer exhibits a lower defect rate during the polishing of the device. In order to further reduce the defect rate, the kinematic viscosity of the polyether polyol in this invention at 40°C is between 600 cSt and 880 cSt.

[0040] In this invention, the ratio of the kinematic viscosity of the polyether polyol at 40°C to that at 25°C is between 0.1 and 0.7. By adjusting the ratio of the kinematic viscosity of the polyether polyol at different temperatures, the sensitivity of the kinematic viscosity to temperature is modulated, ensuring that it maintains a suitable kinematic viscosity at different reaction temperatures. This results in better uniformity of physical properties between polished layers and within a single polished layer, as well as higher grinding rates and lower grinding rate inhomogeneity. To improve the grinding rate and reduce grinding rate inhomogeneity, the ratio of the kinematic viscosity of the polyether polyol at 40°C to that at 25°C in this invention is between 0.43 and 0.52.

[0041] The present invention found that the kinematic viscosity of polyether polyols is significantly less sensitive to temperature at higher temperatures. By controlling it within a certain range, the grinding rate can be further improved and the grinding rate inhomogeneity can be reduced. Therefore, the ratio of the kinematic viscosity of the polyether polyol at 80°C to that at 60°C in the present invention is between 0.6 and 0.7.

[0042] In this invention, the molecular weight of the polyether polyol is between 7,000 and 12,000, and preferably, the molecular weight of the polyether polyol is between 9,500 and 12,000.

[0043] In embodiments of the present invention, the curing agent composition may optionally contain a polyether polyol as shown in Formula 1:

[0044]

[0045] In the polyether polyol represented by chemical formula 1, z is between 3 and 8, R represents a trivalent to octvalent organic group, M represents a divalent organic group, and P represents a monovalent organic group.

[0046] Where z represents the functionality or average functionality of the polyether polyol, which is mainly determined by the functionality or average functionality of the R molecule (initiator), and the two values ​​may be the same or different.

[0047] In this invention, R represents the structural unit of the initiator polyol excluding the hydrogen on the hydroxyl group. For the purpose of controlling the kinematic viscosity of the polyether polyol, the functionality or average functionality of the initiator polyol is between 3 and 8, and preferably the functionality or average functionality of the initiator is between 5 and 7.

[0048] In this invention, R represents the structural unit of the initiator polyol excluding the hydrogen or double bond on the hydroxyl group, which respectively represent sorbitol / glucose, mannitol, glycerol, xylitol, pentaerythritol, and sucrose.

[0049]

[0050] Preferably, R represents the structural unit of the initiator polyol excluding the hydrogen or double bond on the hydroxyl group, which respectively represent sorbitol / glucose, mannitol, and xylitol.

[0051]

[0052] In this invention, M represents a structural segment formed by homopolymerization and / or copolymerization of structural units as shown in structural formula 2 and / or structural formula 3, wherein “*” represents a bonding site:

[0053]

[0054] Among them, structural formula 2 shows the structural segment formed after the ring-opening polymerization of ethylene oxide, and structural formula 3 shows the structural segment formed after the ring-opening polymerization of propylene oxide.

[0055] In this invention, the performance of the polishing layer can be modulated by adjusting the specific addition ratio of ethylene oxide and propylene oxide. The molar amount of the structural unit shown in structural formula 2 is x, and the molar amount of the structural unit shown in structural formula 3 is y. The ratio of x / y is between 0.03 and 1, preferably between 0.03 and 0.5; particularly preferably between 0.08 and 0.3. Controlling x / y within a certain range can effectively control the hardness and resilience of the polishing layer, improve the removal rate of the polishing pad, and effectively reduce the surface defect rate.

[0056] In this invention, P in the chemical formula 1 of the polyether polyol represents a hydrogen atom or a structural unit as shown in structural formula 4. The structural unit shown in structural formula 1 is a structural segment that appears at the end of the molecular chain after the ring-opening of ethylene oxide. For the purpose of improving the polishing rate of the polishing pad and reducing the surface defect rate, preferably, P in the chemical formula 1 of the polyether polyol represents a structural unit as shown in structural formula 4.

[0057]

[0058] The polyether polyols involved in this invention can be synthesized using the following methods. It should be noted that these methods are merely examples of polyether polyol synthesis methods, and other conventional methods in the art can also be used for synthesis. This invention does not limit the synthesis.

[0059] Under normal pressure, a certain amount of initiator polyol and a certain amount of catalyst are added to the reactor. The temperature is controlled at 80-100℃, and the mixture is stirred for 2-5 hours. After evacuation, nitrogen gas is introduced to control the pressure inside the reactor at 0.3 MPa. Then, the pressure is evacuated to 0.095 MPa, and this process is repeated three times to maintain the vacuum state. The reactor temperature is raised to 100-120℃, and a certain amount of propylene oxide is added under vacuum. After the propylene oxide has reacted completely, the pressure is evacuated to above 0.095 MPa, and ethylene oxide is added. The pressure inside the reactor is kept constant, and after reacting for 2-3 hours, a capping agent is added for capping reaction for 0.5 hours. Then, an appropriate amount of phosphoric acid and distilled water are added, and the mixture is stirred for 30-60 minutes. After dehydration, the polyether polyol is obtained by filtration.

[0060] The initiator polyols in this invention include, but are not limited to, one or more combinations of the following compounds: glycerol, trimethylolpropane, pentaerythritol, xylitol, glucose, sorbitol, mannitol, and sucrose; preferably, for suitable functionality or average functionality considerations, the initiator polyol comprises one or more combinations of the following compounds: glycerol, pentaerythritol, xylitol, glucose, sorbitol, mannitol, and sucrose; particularly preferably, the initiator polyol comprises one or more combinations of the following compounds: xylitol, glucose, sorbitol, and mannitol.

[0061] In this invention, the end-capping agent can be any conventional end-capping agent in the art. Preferably, the end-capping agent used in this invention is ethylene oxide.

[0062] The curing agent composition also contains polyamines, including but not limited to: diethyltoluenediamine (DETDA), N,N'-dialkyldiaminodiphenylmethane, 3,5-diethyl-2,4-toluenediamine and its isomers (e.g., 3,5-diethyl-2,6-toluenediamine), 3,5-dimethylthio-2,4-toluenediamine and its isomers, 4,4'-methylene-bis-(2-chloroaniline) (MOCA), 4,4'-bis-(sec-butylamino)-diphenylmethane, 1,4-bis-(sec-butylamino)-benzene, 4,4'-methylene-bis-(2-chloroaniline), 4,4'- -methylene-bis-(3-chloro-2,6-diethylaniline) (M-CDEA), polytetramethylene-di-p-aminobenzoate; p,p'-methylenebisaniline (MDA); m-phenylenediamine (MPDA); 4,4'-methylene-di-(2,6-diethylaniline) (MDEA), 4,4'-methylene-di-(2,3-dichloroaniline) (MDCA), 4,4'-diamino-3,3'-diethyl-5,5'-dimethyldiphenylmethane, 2,2',3,3'-tetrachlorodiaminodiphenylmethane, propylene glycol-di-p-aminobenzoate, or one or more combinations thereof.

[0063] Preferably, the polyamine comprises one or more combinations of diethyltoluenediamine (DETDA), 4,4'-methylene-bis-(2-chloroaniline) (MOCA), and 4,4'-methylene-bis-(3-chloro-2,6-diethylaniline) (MCDEA).

[0064] Particularly preferred is 4,4'-methylene-bis-(2-chloroaniline) (MOCA).

[0065] isocyanate-terminated prepolymers

[0066] In this invention, the isocyanate-terminated prepolymer is obtained by reacting a polyfunctional isocyanate with a polyol.

[0067] The polyfunctional isocyanates in this invention include, but are not limited to, one or more combinations of aromatic isocyanates or aliphatic isocyanates, preferably using aromatic isocyanates of 80 mol% or more, more preferably using aromatic isocyanates of 95 mol% or more, and particularly preferably using aromatic isocyanates of 100 mol% or more.

[0068] Aromatic isocyanates include one or more combinations of 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, 1,5-naphthalene diisocyanate, terephthalic diisocyanate, isophthalic diisocyanate, terephthalimide diisocyanate, and isophthalimide diisocyanate.

[0069] Aliphatic isocyanates include one or more combinations of ethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 1,6-hexamethylene diisocyanate, 1,4-cyclohexane diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, isophorone diisocyanate, and norbornene diisocyanate.

[0070] In this invention, considering the reactivity and physical properties of the polishing pad, one or more combinations of 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, and 4,4'-dicyclohexylmethane diisocyanate are preferred.

[0071] The polyol in the isocyanate-terminated prepolymer of the present invention may include, but is not limited to, polytetramethylene ether glycol (PTMEG), polyethylene glycol (PEG), polypropylene glycol (PPG), and one or more combinations of polytetramethylene ether glycol-polyethylene glycol, polytetramethylene ether glycol-polypropylene glycol, and polyethylene glycol-polypropylene glycol, or a high molecular weight polyol formed by homopolymerization or copolymerization of ethylene glycol, propylene glycol, butanediol, or an initiator having two hydroxyl groups with the above three small molecule diols, or a combination of multiple compositions.

[0072] The polyol in the isocyanate-terminated prepolymer of the present invention may further include small molecule diols, wherein the small molecules include, but are not limited to, one or more combinations of ethylene glycol, 1,3-butanediol, 1,4-butanediol, diethylene glycol, neopentyl glycol, 2-methyl-1,3-propanediol, hexanediol, 3-methyl-1,5-pentanediol, and 1,4-cyclohexanediethanol.

[0073] The isocyanate-terminated prepolymer in this invention can be obtained by purchasing commercially available prepolymer products.

[0074] Commercially available isocyanate-terminated prepolymers include, but are not limited to, any one or more combinations of the following series of prepolymers manufactured by Chemtura: L325, LF800A, LF 900A, LF910A, LF930A, LF931A, LF939A, LF950A, LF952A, LF600D, LF601D, LF650D, LF667D, LF700D, LF750D, LF751D, LF752D, LF753D, LFG963A, LFG964A, and LFG740D.

[0075] In this invention, the isocyanate-terminated prepolymer contains 8.95 to 9.25 wt% unreacted isocyanate groups (-NCO). Preferably, the isocyanate-terminated prepolymer contains L325, whose NCO is 9.1 wt% unreacted isocyanate groups.

[0076] In this invention, the total reactive hydrogen groups in the polyether polyol and polyamine in the curing agent composition, i.e., the ratio of amine NH2 groups and hydroxyl OH groups to the unreacted NCO groups in the isocyanate-terminated prepolymer, i.e., the stoichiometric ratio, is between 0.87 and 1.05.

[0077] Hollow microsphere polymer

[0078] In the polishing layer preparation process, hollow microsphere polymers are usually uniformly dispersed in the polishing layer to adjust the polishing effect of the polishing layer.

[0079] In this invention, the term "hollow microsphere polymer" refers to an expandable hollow polymer microsphere that expands moderately during curing due to the temperature rise caused by the exothermic reaction. By adjusting the distribution (e.g., density) of the hollow microsphere polymer in the polyurethane polishing layer and combining this with adjusting the particle size of the hollow microsphere polymer, the polishing performance of the polishing layer can be further adjusted. Preferably, the hollow microsphere polymer dispersion in the polishing layer results in a final porosity of 10% to 65%.

[0080] Preferably, the hollow microsphere polymer includes, but is not limited to, a capsule structure having an outer wall of polyacrylonitrile and polyacrylonitrile copolymer, and can be purchased from any one of Nouryon, Matsumoto Yushi Pharmaceutical Co., Ltd. or Sekisui Chemicals Co., Ltd. In particular, in the embodiments of the present invention, Nouryon hollow microspheres or Matsumoto microspheres F series are selected.

[0081] In this invention, the density of the polished layer is between 0.7 g / cm³. 3 ~0.9g / cm 3 Preferably, the density of the polished layer is between 0.85 g / cm³. 3 ~0.9g / cm 3 In this invention, the hardness of the polishing layer is between 50D and 63D, preferably between 56D and 60D.

[0082] trench

[0083] In this embodiment of the invention, grooves may be provided on the polishing layer as is conventional in the art. These grooves are used to receive polishing fluid during the polishing process. The grooves can be obtained by processing after the polishing pad is formed. The grooves ensure the smooth discharge and flow of the polishing fluid used during the polishing process. Preferably, the grooves are one or more combinations of concentric circular grooves, radial grooves, XY grid grooves, arc grooves, dot-matrix perforated grooves, spiral grooves, and hexagonal grooves. Particularly preferred are one or more combinations of concentric circular grooves, radial grooves, XY grid grooves, arc grooves, and dot-matrix perforated grooves. The cross-section of the groove is one or more of a straight-sidewall rectangle, a "V" shape, a "U" shape, and a sawtooth shape. Preferably, the cross-section of the groove is a straight-sidewall rectangle.

[0084] Polishing Methods

[0085] The polishing pads involved in this invention can be applied to common semiconductor manufacturing processes. Examples of common processes include, but are not limited to: STI process, Oxide process, W process, Al process, Copper process, and Poly process.

[0086] The polishing method of the present invention includes providing a substrate, which may be selected from at least one of a magnetic substrate, an optical substrate, or a semiconductor substrate; using a polishing pad to form dynamic contact between the polishing surface of the polishing layer and the substrate, thereby polishing the surface of the substrate; and using an abrasive dresser to trim the polished surface.

[0087] Examples of specific polishing methods: using, for example Figure 1The polishing apparatus shown includes a polishing stage 3 supporting a polishing pad 2, a backing material for uniformly pressurizing a support 4 supporting the semiconductor wafer 1 to be polished, and a polishing slurry supply mechanism. The polishing pad 2 is attached to the polishing stage 3, for example, by adhesive adhesion. The polishing stage 3 and the support 4 are configured such that the polishing pad 2 and the semiconductor wafer 1 they support face each other, and each has a rotation axis. Additionally, a pressure mechanism is provided on one side of the support 4 for pressing the semiconductor wafer 1 onto the polishing pad 2. During polishing, the polishing stage 3 and the support 4 are rotated, pressing the semiconductor wafer 1 onto the polishing pad 2, and polishing is performed while slurry is supplied. The slurry flow rate, polishing load, polishing stage speed, and wafer speed are not particularly limited and can be adjusted appropriately.

[0088] Example

[0089] The embodiments of the present invention will be described in detail below with reference to examples. However, those skilled in the art will understand that the following examples are for illustrative purposes only and should not be considered as limiting the scope of the invention. Unless otherwise specified in the examples, conventional conditions or conditions recommended by the manufacturer are followed. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products.

[0090] Explanation of reference numerals in the embodiments:

[0091] L325: L325 isocyanate-terminated prepolymer;

[0092] MOCA: 4,4'-methylene-bis-(2-chloroaniline);

[0093] EO: Ethylene oxide;

[0094] PO: Propylene oxide;

[0095] 920DE 40d30: Nouryon 920DE 40d30, average particle size 40μm, density 0.03g / cm³ 3 ;

[0096] 920DET 40d25: Nouryon 920DET 40d25, average particle size 40μm, density 0.025g / cm³ 3 ;

[0097] 920DE 80d30: Nouryon 920DE 80d30, average particle size 80μm, density 0.03g / cm³ 3 ;

[0098] 043DET 80d20: Nouryon 043DET 80d20, average particle size 80μm, density 0.02g / cm³ 3 ;

[0099] The raw materials mentioned above that do not specify the source of the trademarks are all from commercially available bulk industrial products, and the manufacturers include BASF, Covestro, Wanhua Chemical, Suzhou Xiangyuan, Chizhou Tinci, Mitsui Chemicals, Mitsubishi Chemical, etc.

[0100] Average functionality of initiators

[0101]

[0102] In Formula 1, a1, a2, a n Indicates the functionality of the initiator polyol, M1, M2, M... n This indicates the molar amount of the initiator polyol.

[0103] kinematic viscosity of polyether polyols

[0104] The kinematic viscosity of polyether polyols was measured using the method shown in GB / T 265-1988.

[0105] Molecular weight of polyether polyols

[0106] Measurement using GPC

[0107] Agilent PLgel single-pore column, part number PL1110-6530, 7.5×300mm, with guard column, part number PL110-1520, 7.5×50mm; column temperature: 40℃; mobile phase: chromatographic grade tetrahydrofuran; mobile phase flow rate: 0.7mL / min; detector: differential detector; test sample injection volume: 20μL.

[0108] Shore hardness of polished layer

[0109] The REX digital Shore D-type automatic hardness tester and the Bareiss digital Shore D-type automatic hardness tester were used for measurement. The sample to be tested was punched into a 3"×3" square sample. The thickness of the sample to be tested was not less than 5mm. The measurement point was at least 9mm away from any edge of the sample. The hardness values ​​were measured at least 6mm apart on the same sample. The maximum value was taken. The sample was tested in a standard environment of 23±2℃ and 50%±10% humidity.

[0110] Density of polished layer

[0111] Calculate using the following formula: SG=m / v=m / (π(d / 2)^2*h), where m is the weight of the polished layer, d is the diameter of the polished layer, and h is the thickness of the polished layer.

[0112] Polishing performance evaluation of polishing pads

[0113] The polishing pads used in the prepared examples and comparative examples were tested on a machine to evaluate their polishing performance. The test conditions are as follows:

[0114] The test equipment was an AMAT Refelxion (Modify 5Zone);

[0115] The polishing wafer was a Cu 10K wafer, the polishing slurry was a diluted solution of ANJI U3061A (10 times), with an additional 1% wtH2O2, the flow rate was 230 ml / min, the dressing device was a Saesol AK53 diamond disk, the pressure was 6 lbf, the polishing head pressure was 2.7 psi, the stage speed was 77 rpm, the carrier speed was 71 rpm, and the polishing time was 30 s.

[0116] The grinding rate was measured on the 10th wafer, and the grinding non-uniformity was measured on 100 wafers.

[0117] Defect rating

[0118] Defects on the material after polishing the substrate can be obtained using KLA-Tencor. The SP2 defect inspection system was used to inspect the wafers, detecting a defect size of 0.16 μm on the 10th wafer.

[0119] Synthesis example 1

[0120] 1 mol of mannitol and 0.05 mol of KOH were added to the reactor under normal pressure, and the temperature was controlled at 80℃. The mixture was stirred for 3 hours. After evacuation, nitrogen gas was introduced to control the pressure inside the reactor at 0.3 MPa. The pressure was then evacuated to 0.095 MPa, and this process was repeated three times to maintain the vacuum state. The reactor temperature was raised to 110℃, and 10 mol of PO was added under vacuum. After the PO had reacted completely, the pressure was evacuated to above 0.095 MPa, and 2 mol of EO was added. The pressure inside the reactor was kept constant. After reacting for 2 hours, 0.2 mol of EO was added, and the reaction was carried out for 0.5 hours. Then, 0.01 mol of phosphoric acid and distilled water were added. After stirring for 30 minutes, the mixture was dehydrated and filtered to obtain polyether polyol-M1, with a molecular weight of 11100.

[0121] Synthesis example 2

[0122] 1 mol of sorbitol and 0.05 mol of KOH were added to the reactor under normal pressure, and the temperature was controlled at 80℃. The mixture was stirred for 3 hours. After evacuation, nitrogen gas was introduced to control the pressure inside the reactor at 0.3 MPa. The pressure was then evacuated to 0.095 MPa, and this process was repeated three times to maintain the vacuum state. The reactor temperature was raised to 110℃, and 9.76 mol of PO was added under vacuum. After the PO had reacted completely, the pressure was evacuated to above 0.095 MPa, and 2.24 mol of EO was added. The pressure inside the reactor was kept constant. After reacting for 2 hours, 0.2 mol of EO was added, and the reaction was carried out for 0.5 hours. Then, 0.01 mol of phosphoric acid and distilled water were added. After stirring for 30 minutes, the mixture was dehydrated and filtered to obtain polyether polyol-M2, with a molecular weight of 11500.

[0123] Synthesis example 3

[0124] 1 mol of glucose and 0.05 mol of KOH were added to the reactor under normal pressure, and the temperature was controlled at 80℃. The mixture was stirred for 3 hours. After evacuation, nitrogen gas was introduced to control the pressure inside the reactor at 0.3 MPa. The pressure was then evacuated to 0.095 MPa, and this process was repeated three times to maintain the vacuum state. The reactor temperature was raised to 110℃, and 8 mol of PO was added under vacuum. After the PO had reacted completely, the pressure was evacuated to above 0.095 MPa, and 4 mol of EO was added. The pressure inside the reactor was kept constant. After reacting for 2 hours, 0.2 mol of EO was added, and the reaction was carried out for 0.5 hours. Then, 0.01 mol of phosphoric acid and distilled water were added, and the mixture was stirred for 30 minutes. After dehydration and filtration, polyether polyol-M3 was obtained. The molecular weight of M3 was 11750.

[0125] Synthesis example 4

[0126] 1 mol of pentaerythritol and 0.05 mol of KOH were added to the reactor under normal pressure, and the temperature was controlled at 80℃. The mixture was stirred for 3 hours. After evacuation, nitrogen gas was introduced to control the pressure inside the reactor at 0.3 MPa. The pressure was then evacuated to 0.095 MPa, and this process was repeated three times to maintain the vacuum state. The reactor temperature was raised to 110℃, and 5.33 mol of PO was added under vacuum. After the PO had reacted completely, the pressure was evacuated to above 0.095 MPa, and 2.67 mol of EO was added. The pressure inside the reactor was kept constant, and after reacting for 2 hours, 0.2 mol of EO was added. After reacting for 0.5 hours, 0.01 mol of phosphoric acid and distilled water were added. After stirring for 30 minutes, the mixture was dehydrated and filtered to obtain polyether polyol-M4, with a molecular weight of 8800.

[0127] Synthesis example 5

[0128] 1 mol of glycerol and 0.05 mol of KOH were added to the reactor under normal pressure, and the temperature was controlled at 80℃. The mixture was stirred for 3 hours. After evacuation, nitrogen gas was introduced to control the pressure inside the reactor at 0.3 MPa. The pressure was then evacuated to 0.095 MPa, and this process was repeated three times to maintain the vacuum state. The reactor temperature was raised to 110℃, and 5.83 mol of PO was added under vacuum. After the PO had reacted completely, the pressure was evacuated to above 0.095 MPa, and 0.17 mol of EO was added. The pressure inside the reactor was kept constant, and after 2 hours of reaction, 0.2 mol of EO was added. After 0.5 hours of reaction, 0.01 mol of phosphoric acid and distilled water were added. The mixture was stirred for 30 minutes, and after dehydration and filtration, polyether polyol-M5 was obtained. The molecular weight of M5 was 7500.

[0129] Synthesis example 6

[0130] 1 mol of sucrose and 0.05 mol of KOH were added to the reactor under normal pressure, and the temperature was controlled at 80℃. The mixture was stirred for 3 hours. After evacuation, nitrogen gas was introduced to control the pressure inside the reactor at 0.3 MPa. The pressure was then evacuated to 0.095 MPa, and this process was repeated three times to maintain the vacuum state. The reactor temperature was raised to 110℃, and 9.01 mol of PO was added under vacuum. After the PO had reacted completely, the pressure was evacuated to above 0.095 MPa, and 0.99 mol of EO was added. The pressure inside the reactor was kept constant, and after 2 hours of reaction, 0.2 mol of EO was added. After 0.5 hours of reaction, 0.01 mol of phosphoric acid and distilled water were added. The mixture was stirred for 30 minutes, and after dehydration and filtration, polyether polyol-M6 was obtained. The molecular weight of M6 was 9980.

[0131] Synthesis Example 7

[0132] 1 mol of sucrose and 0.05 mol of KOH were added to the reactor under normal pressure, and the temperature was controlled at 80℃. The mixture was stirred for 3 hours. After evacuation, nitrogen gas was introduced to control the pressure inside the reactor at 0.3 MPa. The pressure was then evacuated to 0.095 MPa, and this process was repeated three times to maintain the vacuum state. The reactor temperature was raised to 110℃, and 15.53 mol of PO was added under vacuum. After the PO had reacted completely, the pressure was evacuated to above 0.095 MPa, and 0.47 mol of EO was added. The pressure inside the reactor was kept constant. After reacting for 2 hours, 0.2 mol of EO was added, and after reacting for 0.5 hours, 0.01 mol of phosphoric acid and distilled water were added. After stirring for 30 minutes, the mixture was dehydrated and filtered to obtain polyether polyol-M7, with a molecular weight of 13800.

[0133] Synthesis example 8

[0134] Under normal pressure, 0.74 mol of sucrose, 0.26 mol of glycerol, and 0.05 mol of KOH were added to the reactor. The temperature was controlled at 80℃, and the mixture was stirred for 3 hours. After evacuation, nitrogen gas was introduced to control the pressure inside the reactor at 0.3 MPa. The pressure was then evacuated to 0.095 MPa, and this process was repeated three times to maintain the vacuum state. The reactor temperature was raised to 110℃, and 12.41 mol of PO was added under vacuum. After the PO had reacted completely, the pressure was evacuated to above 0.095 MPa, and 0.99 mol of EO was added. The pressure inside the reactor was kept constant, and after reacting for 2 hours, 0.2 mol of EO was added. After reacting for 0.5 hours, 0.01 mol of phosphoric acid and distilled water were added. After stirring for 30 minutes, the mixture was dehydrated and filtered to obtain polyether polyol-M8, with a molecular weight of 12100.

[0135] Synthesis example 9

[0136] Under normal pressure, 0.43 mol of sorbitol, 0.67 mol of glycerol, and 0.05 mol of KOH were added to a reactor, and the temperature was controlled at 80℃. The mixture was stirred for 3 hours. After evacuation, nitrogen gas was introduced to control the pressure inside the reactor at 0.3 MPa. The pressure was then evacuated to 0.095 MPa, and this process was repeated three times to maintain the vacuum state. The reactor temperature was raised to 110℃, and 6.32 mol of PO was added under vacuum. After the PO had reacted completely, the pressure was evacuated to above 0.095 MPa, and 2.28 mol of EO was added. The pressure inside the reactor was kept constant, and after reacting for 2 hours, 0.2 mol of EO was added. After reacting for 0.5 hours, 0.01 mol of phosphoric acid and distilled water were added. After stirring for 30 minutes, the mixture was dehydrated and filtered to obtain polyether polyol-M9, with a molecular weight of 9200.

[0137] Synthesis example 10

[0138] Under normal pressure, 0.2 mol of pentaerythritol, 0.8 mol of xylitol, and 0.05 mol of KOH were added to the reactor, and the temperature was controlled at 80℃. The mixture was stirred for 3 hours. After evacuation, nitrogen gas was introduced to control the pressure inside the reactor at 0.3 MPa. The pressure was then evacuated to 0.095 MPa and repeated three times to maintain the vacuum state. The reactor temperature was raised to 110℃, and 9.6 mol of EO was added under vacuum. The pressure inside the reactor was kept constant. After reacting for 2 hours, 0.2 mol of EO was added, and after reacting for 0.5 hours, 0.01 mol of phosphoric acid and distilled water were added. After stirring for 30 minutes, the mixture was dehydrated and filtered to obtain polyether polyol-M10, with a molecular weight of 8900.

[0139] Synthesis example 11

[0140] 1 mol of pentaerythritol and 0.05 mol of KOH were added to the reactor under normal pressure, and the temperature was controlled at 80℃. The mixture was stirred for 3 hours. After evacuation, nitrogen gas was introduced to control the pressure inside the reactor at 0.3 MPa. The pressure inside the reactor was then evacuated to 0.095 MPa and repeated three times to maintain the vacuum state. The temperature of the reactor was raised to 110℃, and 8 mol of epoxide was added under vacuum. After the PO reaction was complete, the pressure inside the reactor was evacuated to above 0.095 MPa. The pressure inside the reactor was kept constant. After reacting for 2 hours, 0.2 mol of EO was added and reacted for 0.5 hours. Then, 0.01 mol of phosphoric acid and distilled water were added and stirred for 30 minutes. After dehydration, the mixture was filtered to obtain polyether polyol-M11, with a molecular weight of 8600.

[0141] Synthesis example 12

[0142] 1 mol of glucose and 0.05 mol of KOH were added to the reactor under normal pressure, and the temperature was controlled at 80℃. The mixture was stirred for 3 hours. After evacuation, nitrogen gas was introduced to control the pressure inside the reactor at 0.3 MPa. The pressure was then evacuated to 0.095 MPa, and this process was repeated three times to maintain the vacuum state. The reactor temperature was raised to 110℃, and 5.9 mol of PO was added under vacuum. After the PO had reacted completely, the pressure was evacuated to above 0.095 MPa, and 6.1 mol of EO was added. The pressure inside the reactor was kept constant. After reacting for 2 hours, 0.2 mol of EO was added, and the reaction was carried out for 0.5 hours. Then, 0.01 mol of phosphoric acid and distilled water were added. After stirring for 30 minutes, the mixture was dehydrated and filtered to obtain polyether polyol-M12, with a molecular weight of 11400.

[0143] Synthesis example 13

[0144] 1 mol of ethylene glycol and 0.05 mol of KOH were added to the reactor under normal pressure, and the temperature was controlled at 80℃. The mixture was stirred for 3 hours. After evacuation, nitrogen gas was introduced to control the pressure inside the reactor at 0.3 MPa. The pressure was then evacuated to 0.095 MPa, and this process was repeated three times to maintain the vacuum state. The reactor temperature was raised to 110℃, and 2.65 mol of PO was added under vacuum. After the PO had reacted completely, the pressure was evacuated to above 0.095 MPa, and 1.35 mol of EO was added. The pressure inside the reactor was kept constant, and after 2 hours of reaction, 0.2 mol of EO was added. After 0.5 hours of reaction, 0.01 mol of phosphoric acid and distilled water were added. After stirring for 30 minutes, the mixture was dehydrated and filtered to obtain polyether polyol-M13, with a molecular weight of 6200.

[0145] Synthesis example 14

[0146] Under normal pressure, 0.9 mol of sucrose, 0.1 mol of mannitol, and 0.05 mol of KOH were added to the reactor, and the temperature was controlled at 80℃. The mixture was stirred for 3 hours. After evacuation, nitrogen gas was introduced to control the pressure inside the reactor at 0.3 MPa. The pressure was then evacuated to 0.095 MPa, and this process was repeated three times to maintain the vacuum state. The reactor temperature was raised to 110℃, and 13 mol of PO was added under vacuum. After the PO had reacted completely, the pressure was evacuated to above 0.095 MPa, and 2.6 mol of EO was added. The pressure inside the reactor was kept constant, and after reacting for 2 hours, 0.2 mol of EO was added. After reacting for 0.5 hours, 0.01 mol of phosphoric acid and distilled water were added. After stirring for 30 minutes, the mixture was dehydrated and filtered to obtain polyether polyol-M14, with a molecular weight of 12300.

[0147] The physical properties of the polyether polyols M1 to M14 prepared in Synthetic Examples 1 to 14 are shown in Table 1:

[0148] Table 1

[0149]

[0150] Example 1

[0151] This embodiment provides a polishing pad, which is prepared by the following method:

[0152] Step 1: Take 100 parts by weight of L325 isocyanate-terminated prepolymer, heat to 25-65℃, degas under vacuum (-0.095MPa) for 2 hours, then add 1.54 parts by weight of hollow microsphere polymer 551DE40d42 with an average particle size of 40μm, stir to make the hollow microsphere polymer uniformly dispersed in the prepolymer, and degas again under vacuum (-0.095MPa) for 2 hours, and set aside for use.

[0153] Step 2: Maintain the curing agent composition: 28.6 parts by weight of MOCA at 115°C and 4.8 parts by weight of polyether polyol M12 at 25-65°C.

[0154] Step 3: Mix the prepolymer and curing agent composition under high-speed shearing, then pour it into a circular mold to form a 12cm thick casting block. Let it stand at room temperature for 10 minutes, then place it in a 100℃ oven to cure for 16 hours. After curing, allow it to automatically cool to room temperature in the oven, then cut it into 80mil thick sheets, for a total of 60 sheets.

[0155] Step 4: Select a groove shape that uses concentric circular grooves with a blank (ungrooved) area in the center. The grooving parameters are: groove depth 30mil, groove width 20mil, groove spacing 120mil, and the diameter of the blank area in the center is 2 inches. After grooving, the polishing layer is formed.

[0156] Step 5: For the intermediate adhesive and backing adhesive layer, double-sided tape (purchased from Sekisui Chemicals and 3M) is used. The intermediate adhesive is used to bond the polishing layer and the buffer layer, and the backing adhesive layer is bonded to the other side of the buffer layer (the side where the polishing layer is not bonded). This will give you the polishing pad P1. The buffer layer uses polyurethane-impregnated non-woven fabric material Z70 (purchased from Dinglong Co., Ltd.).

[0157] Examples 2 to 12 provide polishing pads P2 to P12 respectively, and Comparative Examples 1 to 3 provide polishing pads PD1 to PD3 respectively. Except for the difference in the ratio of polishing layer raw materials compared with Example 1, their preparation methods are the same as those of Example 1. The ratio of polishing layer raw materials in Examples 2 to 12 and Comparative Examples 1 to 3 is shown in Table 2.

[0158] Table 2

[0159]

[0160] The evaluation results of polishing pads P1-12 and PD1-3 on the machine are shown in Table 3.

[0161] Table 3

[0162]

[0163] It should be noted that, based on the explanations and descriptions in the foregoing specification, those skilled in the art can make changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some equivalent modifications and alterations to the present invention should also be within the scope of protection of the claims of the present invention. Furthermore, although some specific terms are used in this specification, these terms are only for convenience of explanation and do not constitute any limitation on the invention.

Claims

1. A polishing pad, characterized in that, A polished layer having a polished surface, the polished layer comprising a reaction product of the following components: an isocyanate-terminated prepolymer and a curing agent composition; the curing agent composition comprising a polyamine and a polyether polyol, the polyether polyol having a kinematic viscosity at 40°C between 130 cSt and 1100 cSt, and the ratio of the kinematic viscosity of the polyether polyol at 40°C to its kinematic viscosity at 25°C being between 0.1 and 0.

7.

2. The polishing pad according to claim 1, characterized in that, The structure of the polyether polyol is shown in Chemical Formula 1: Chemical Formula 1 In the polyether polyol represented by chemical formula 1, z is between 3 and 8, R represents a trivalent to octvalent organic group, M represents a divalent organic group, and P represents a monovalent organic group.

3. The polishing pad according to claim 2, characterized in that, In the chemical formula 1, M represents a structural segment formed by homopolymerization and / or copolymerization of structural units as shown in structural formula 2 and / or structural formula 3, where "*" represents a bonding site. Structural Formula 2 Structural formula 3.

4. The polishing pad according to claim 3, characterized in that, The molar quantity of the structural unit shown in structural formula 2 is x, and the molar quantity of the structural unit shown in structural formula 3 is y, where x / y is between 0.03 and 1.

5. The polishing pad according to claim 4, characterized in that, The x / y ratio is between 0.03 and 0.

5.

6. The polishing pad according to claim 4, characterized in that, The x / y ratio is between 0.08 and 0.

3.

7. The polishing pad according to claim 2, characterized in that, In the chemical formula 1 of the polyether polyol, P represents a hydrogen atom.

8. The polishing pad according to claim 2, characterized in that, In the polyether polyol chemical formula 1, P represents the structural unit as shown in structural formula 4: Structure 4.

9. The polishing pad according to claim 2, characterized in that, In the polyether polyol chemical formula 1, R represents one or more combinations of structural units as shown in structural formula 5-1, where "*" represents a bonding site. Structural formula 5-1.

10. The polishing pad according to claim 2, characterized in that, In the polyether polyol of formula 1, R represents one or more combinations of structural units as shown in structural formula 5-2, where "*" represents a bonding site. Structural formula 5-2.

11. The polishing pad according to claim 1, characterized in that, The curing agent composition comprises one or more of the following polyamines: diethyltoluenediamine (DETDA), 4,4'-methylene-bis-(2-chloroaniline) (MOCA), and 4,4'-methylene-bis-(3-chloro-2,6-diethylaniline) (MCDEA).

12. The polishing pad according to claim 1, characterized in that, The ratio of the kinematic viscosity of the polyether polyol at 80°C to its kinematic viscosity at 60°C is between 0.6 and 0.

7.

13. The polishing pad according to claim 1, characterized in that, The kinematic viscosity of the polyether polyol at 40°C is between 600 cSt and 880 cSt, and the ratio of the kinematic viscosity of the polyether polyol at 40°C to the kinematic viscosity at 25°C is between 0.43 and 0.

52.

14. The polishing pad according to claim 1, characterized in that, The molecular weight (Mw) of the polyether polyol is between 7000 and 12000.

15. The polishing pad according to claim 1, characterized in that, The molecular weight (Mw) of the polyether polyol is between 9500 and 12000.

16. The polishing pad according to claim 1, characterized in that, The curing agent composition has a plurality of reactive hydrogen groups, the isocyanate-terminated prepolymer has a plurality of unreacted NCO groups, the isocyanate-terminated prepolymer contains 8.95wt% to 9.25wt% of unreacted NCO groups, and the stoichiometric ratio of the reactive hydrogen groups to the unreacted NCO groups is between 0.87 and 1.

05.

17. The polishing pad according to claim 1, characterized in that, The density of the polished layer is between 0.7 g / cm³ and 0.9 g / cm³, and the hardness of the polished layer is between 50D and 63D.

18. A polishing method, characterized in that, A substrate is provided, the substrate being selected from at least one of magnetic substrates, optical substrates, or semiconductor substrates, and a polishing pad as described in any one of claims 1 to 17 is provided, forming a dynamic contact between the polishing surface of the polishing layer and the substrate, thereby polishing the surface of the substrate, and the polishing surface is trimmed using an abrasive dresser.

Images