Polishing pad and polishing method

Abstract

The present invention provides a polishing pad, a polishing layer having a polishing surface wherein the polishing layer comprises a reaction product comprising an isocyanate-terminated prepolymer and a curing agent composition wherein the curing agent composition comprises a polyamine and a polyether polyol having a kinematic viscosity at 40 DEG C between 130 cSt and 1100 cSt, and wherein the polyether polyol has a kinematic viscosity at 40 DEG C between 130 cSt and 1100 cSt. The ratio of the kinematic viscosity of the polyether polyol at the temperature of 40 DEG C to the kinematic viscosity of the polyether polyol at the temperature of 25 DEG C is 0.1-0.7; by controlling the kinematic viscosity of the polyether polyol in the curing agent composition at a certain temperature and the ratio of the kinematic viscosity at different temperatures, the polishing pad which is higher in grinding rate, lower in defect and lower in grinding rate heterogeneity is prepared.

Description

Technical Field

[0001] The invention relates to the technical field of polishing of chemical mechanical planarization treatment, and in particular to a polishing pad and a method for manufacturing a semiconductor device. Background Art

[0002] CMP technology is a technology that places the surface of the device to be processed facing downward, applies a certain pressure to the polishing pad, and under the action of the polishing liquid, uses the relative movement of the polishing pad and the device to be processed to remove the material on the surface of the device to be processed through mechanical grinding of the abrasive particles and chemical corrosion of the oxidant, thereby obtaining a flat surface.

[0003] With the development of the semiconductor industry, the trend of processing technology is shifting towards higher current density, higher clock frequency and more interconnection layers. Due to the reduction of the size of the chip and the reduction of the focal depth of the lithography equipment, the flatness of the acceptable resolution of the chip surface is required to reach the nanometer level. Traditional flattening technologies such as selective deposition based on deposition technology, sputtered glass SOG, low-pressure CVD, plasma-enhanced CVD and other technologies can also provide a smooth surface, but they are all local flattening technologies and cannot achieve global flattening. It is generally believed internationally that when the device feature size is below 0.35μm, global flattening must be performed to ensure the accuracy and resolution of the lithography transmission. CMP technology is currently recognized internationally as the only technology that can achieve global flattening. The CMP yield seriously affects the yield of the chip.

[0004] With the sharp increase in market demand for chips, there has been a shortage of chips in the past two years. Although advanced process chips such as 5nm and 3nm are known to the public with products such as mobile phones, the current market is still dominated by mature processes. Although mature processes have relatively low requirements for CMP consumables, they have extremely stringent requirements on CMP consumables, especially polishing pads, such as 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] In order to solve the problems in the prior art, the present invention provides a polishing pad having a polishing layer on a polishing surface, wherein the polishing layer comprises a reaction product of the following components: an isocyanate-terminated prepolymer and a curing agent composition; the curing agent composition comprises 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 the 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 as shown in Chemical Formula 1, z is between 3 and 8, R represents a 3-8 valent organic group, M represents a 2-valent organic group, and P represents a 1-valent organic group;

[0009] Preferably, M in the chemical formula 1 represents a structural fragment 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 amount of the structural unit shown in the structural formula 2 is x, and the molar amount of the structural unit shown in the 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, P in the polyether polyol chemical formula 1 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, wherein "*" 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 formula 5-2, wherein "*" represents a bonding site:

[0019]

[0020] Further, the curing agent composition comprises one or more combinations of the following polyamines: diethyltoluenediamine (DETDA), 4,4'-methylene-bis-(2-chloroaniline) (MOCA), 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 the 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] Further, 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; further, 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;

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

[0026] The second aspect of the present invention is a polishing method, characterized in that a substrate is provided, wherein the substrate is selected from at least one of a magnetic substrate, an optical substrate or a semiconductor substrate, the above-mentioned polishing pad is provided, dynamic contact is formed 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 polishing surface.

[0027] Beneficial Effects

[0028] The present invention is designed through the curing system in the polishing layer raw material in the polishing pad, and the polishing performance is improved by controlling the kinematic viscosity of the polyether polyol and the change of the kinematic viscosity at different temperatures. When the kinematic viscosity of the polyether polyol is controlled within a certain range at 40°C, the polyether polyol has more suitable fluidity during the curing reaction of the polishing layer, and the prepared polishing layer shows a lower defect rate. In addition, by controlling the ratio of the kinematic viscosity of the polyether polyol at 40°C to that at 25°C, the sensitivity of the kinematic viscosity of the polyether polyol to temperature is modulated, and the polishing pad prepared by controlling it within a certain range has a higher grinding rate and lower grinding rate heterogeneity. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0030] Figure 1 A schematic diagram of a polishing operation process performed by a polishing pad according to 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- bracket; 5- polishing liquid; 20- polishing layer; 21- adhesive layer; 22- buffer layer; 23- adhesive layer. DETAILED DESCRIPTION

[0033] The present invention is described in detail below.

[0034] <Polishing pad>

[0035] The polishing pad of the present invention is as follows Figure 2 As shown, it includes a polishing layer 20, a buffer layer 22, an adhesive layer 21 and a back adhesive layer 23. The polishing pad in the present invention is arranged from top to bottom as a polishing layer 20, an adhesive layer 21, a buffer layer 22, and a back adhesive layer 23, wherein the adhesive layer 21 is used for bonding the polishing layer 20 and the buffer layer 22, and the back adhesive layer 23 also includes a release film or a release paper. When in use, the release film or the release paper can be torn off to achieve the bonding of 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 of the following components: an isocyanate-terminated prepolymer and a curing agent composition.

[0038] Curing agent composition

[0039] The curing agent composition of the present invention comprises a polyether polyol, wherein the kinematic viscosity of the polyether polyol at 40° C. is between 130 cSt and 1100 cSt. The polyether polyol of the present 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 process of polishing the device. In order to further reduce the defect rate, the kinematic viscosity of the polyether polyol at 40° C. in the present invention is between 600 cSt and 880 cSt.

[0040] The ratio of the kinematic viscosity of the polyether polyol at 40°C to that at 25°C in the present invention is between 0.1 and 0.7. By regulating the ratio of the kinematic viscosity of the polyether polyol at different temperatures, the sensitivity of the kinematic viscosity to temperature is adjusted, so that the appropriate kinematic viscosity is maintained at different reaction temperatures. The prepared polishing layer sheets and the single polishing layer have better uniformity of physical properties, and have a higher grinding rate and lower grinding rate heterogeneity. In order to increase the grinding rate and reduce the grinding rate heterogeneity, the ratio of the kinematic viscosity of the polyether polyol at 40°C to that at 25°C in the present invention is between 0.43 and 0.52.

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

[0042] The molecular weight of the polyether polyol in the present invention is between 7000 and 12000, and preferably, the molecular weight of the polyether polyol is between 9500 and 12000.

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

[0044]

[0045] In the polyether polyol shown in Chemical Formula 1, z is between 3 and 8, R represents a trivalent to octavalent organic group, M represents a divalent organic group, and P represents a monovalent organic group.

[0046] Wherein 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 the present invention, R represents the structural unit of the initiator polyol except the hydrogen on the hydroxyl group. In order to control the kinematic viscosity of the polyether polyol, the functionality or average functionality of the initiator polyol is between 3 and 8, and the preferred functionality or average functionality of the initiator is between 5 and 7.

[0048] In the present invention, R represents a structural unit of the initiator polyol of the following structure except for hydrogen or double bonds on the hydroxyl group, which respectively represent sorbitol / glucose, mannitol, glycerol, xylitol, pentaerythritol, and sucrose.

[0049]

[0050] Preferably, R represents a structural unit of an initiator polyol of the following structure except for hydrogen or double bonds on hydroxyl groups, which respectively represent sorbitol / glucose, mannitol, and xylitol.

[0051]

[0052] In the present invention, M represents a structural fragment 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] Wherein, the structural fragment formed by the ring-opening polymerization of ethylene oxide is shown in structural formula 2, and the structural fragment formed by the ring-opening polymerization of propylene oxide is shown in structural formula 3.

[0055] In the present invention, the performance of the polishing layer can be adjusted 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, the molar amount of the structural unit shown in structural formula 3 is y, and x / y is between 0.03 and 1. Preferably, x / y is between 0.03 and 0.5; particularly preferably, x / y is 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 the polyether polyol chemical formula 1 of the present invention, P represents a hydrogen atom or a structural unit as shown in structural formula 4, wherein the structural unit shown in structural formula 1 is a structural fragment that appears at the end of the molecular chain after the ring opening of ethylene oxide. In order to improve the polishing rate of the polishing pad and reduce the surface defect rate, preferably, P in the polyether polyol chemical formula 1 represents a structural unit as shown in structural formula 4:

[0057]

[0058] The polyether polyols involved in the present invention can be synthesized using the following method. It should be noted that this method is only an example of a method for synthesizing polyether polyols. Other conventional methods in the art can also be used for synthesis, and the present invention does not limit this.

[0059] Add a certain amount of initiator polyol and a certain amount of catalyst into the reactor under normal pressure, control the temperature at 80-100°C, and stir for 2-5h; introduce nitrogen after evacuation to control the pressure in the reactor to 0.3MPa, then evacuate to 0.095MPa, repeat three times to maintain the vacuum state; raise the temperature of the reactor to 100-120°C, add a certain amount of propylene oxide in a vacuum state, and after the propylene oxide reacts completely, evacuate to above 0.095MPa, and add ethylene oxide; control the pressure in the reactor to remain unchanged, add a capping agent after reacting for 2-3 hours, perform capping reaction for 0.5h, then add appropriate amount of phosphoric acid and distilled water, stir for 30-60min, dehydrate, and filter to obtain polyether polyol.

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

[0061] The end-capping agent in the present invention can be selected from conventional end-capping agents in the art. Preferably, the end-capping agent in the present invention is selected from ethylene oxide.

[0062] The curing agent composition further comprises a polyamine, wherein the polyamine includes but is 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'-diamino-2,4-toluenediamine, ... -methylene-bis-(3-chloro-2,6-diethylaniline) (M-CDEA), polyoxytetramethylene-di-p-aminobenzoate; p,p'-methylenedianiline (MDA); metaphenylenediamine (MPDA); 4,4'-methylene-bis-(2,6-diethylaniline) (MDEA), 4,4'-methylene-bis-(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: diethyltoluenediamine (DETDA), 4,4'-methylene-bis-(2-chloroaniline) (MOCA), 4,4'-methylene-bis-(3-chloro-2,6-diethylaniline) (MCDEA), or one or more combinations thereof.

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

[0065] Isocyanate-terminated prepolymers

[0066] The isocyanate-terminated prepolymer of the present invention is obtained by reacting multifunctional isocyanate and polyol.

[0067] The polyfunctional isocyanate in the present invention includes but is not limited to one or more combinations of aromatic isocyanates or aliphatic isocyanates. It is preferred to use more than 80 mol % of aromatic isocyanates, further preferably more than 95 mol % of aromatic isocyanates, and particularly preferably 100 mol % of aromatic isocyanates.

[0068] The aromatic isocyanate includes 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, p-phenylene diisocyanate, m-phenylene diisocyanate, p-xylylene diisocyanate, and m-xylylene diisocyanate.

[0069] The aliphatic isocyanate includes 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 norbornane diisocyanate.

[0070] In the present invention, in consideration of the reaction activity 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 preferably used.

[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, 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 variety of combinations.

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

[0073] The isocyanate-terminated prepolymer in the present 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 series of prepolymers produced 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] The isocyanate-terminated prepolymer of the present invention contains 8.95-9.25 wt % of unreacted isocyanate groups (-NCO). Preferably, the isocyanate-terminated prepolymer of the present invention contains L325, whose NCO is 9.1 wt % of unreacted isocyanate groups.

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

[0077] Hollow microsphere polymer

[0078] In the process of preparing the polishing layer, the hollow microsphere polymer is usually evenly dispersed in the polishing layer, so as to adjust the polishing effect of the polishing layer.

[0079] The term "hollow microsphere polymer" in the embodiments of the present invention refers to an expandable hollow polymer microsphere that can moderately expand during the curing process by virtue of the temperature rise caused by the reaction exotherm. The polishing performance of the polishing layer can be further adjusted by adjusting the distribution mode (such as density) of the hollow microsphere polymer in the polyurethane polishing layer and adjusting the particle size of the hollow microsphere polymer. Preferably, the hollow microsphere polymer is dispersed in the polishing layer so that the final porosity of the polishing layer is 10% to 65%.

[0080] Preferably, the hollow microsphere polymer includes but is not limited to a vesicular structure having an outer wall of polyacrylonitrile and polyacrylonitrile copolymer, and can be purchased from microspheres or microbeads of any one of Nouryon, Matsumoto Oil & Fats Pharmaceutical Co., Ltd. or Sekisui Chemical Co., Ltd. Particularly preferably, in the embodiment of the present invention, Nouryon hollow microspheres or Matsumoto microbeads F series are selected.

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

[0082] Grooves

[0083] In an embodiment of the present invention, the polishing layer may be provided with grooves according to the conventional art, and the grooves are used to receive the polishing liquid during the polishing process. The grooves can be obtained by processing after the polishing pad is formed. The arrangement of the grooves can ensure the smooth discharge and flow of the polishing liquid used in the polishing process. Preferably, the grooves are one or more combinations of concentric grooves, radial grooves, XY grid grooves, arc grooves, lattice perforated grooves, spiral grooves, and hexagonal grooves. Particularly preferably, the grooves are one or more combinations of concentric grooves, radial grooves, XY grid grooves, arc grooves, and lattice 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 method>

[0085] The polishing pad involved in the present invention can be applied to commonly used semiconductor 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 involved in the present invention is to provide a substrate, which can be selected from at least one of a magnetic substrate, an optical substrate or a semiconductor substrate, use 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 use an abrasive dresser to dress the polishing surface.

[0087] Examples of specific polishing methods: Use Figure 1The polishing device shown in the figure is carried out, and the polishing device has a polishing machine table 3 supporting a polishing pad 2, a support 4 supporting a material to be polished-a semiconductor wafer 1 and a backing material for uniformly pressurizing the wafer, and a supply mechanism for a polishing liquid 5. The polishing pad 2 is mounted on the polishing machine table 3, for example, by adhering a backing layer. The polishing machine table 3 and the support 4 are configured so that the polishing pad 2 and the semiconductor wafer 1 supported by each are opposite to each other, and each has a rotation axis. In addition, a pressurizing mechanism for pressing the semiconductor wafer 1 onto the polishing pad 2 is provided on one side of the support 4. When polishing, the polishing machine table 3 and the support 4 are rotated, and the semiconductor wafer 1 is pressed onto the polishing pad 2, and polishing is performed while supplying slurry. There are no special restrictions on the flow rate of the slurry, the polishing load, the rotation speed of the polishing machine table, and the rotation speed of the wafer, and they can be adjusted appropriately.

[0088] Example

[0089] The embodiments of the present invention will be described in detail below in conjunction with the examples, but those skilled in the art will appreciate that the following examples are only used to illustrate the present invention and should not be considered to limit the scope of the invention. If no specific conditions are specified in the examples, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased commercially.

[0090] Explanation of the 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 / cm 3 ;

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

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

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

[0099] The above-mentioned raw materials without trademark origin are all from bulk industrial products on the market, and the manufacturers include BASF, Covestro, Wanhua Chemical, Suzhou Xiangyuan, Chizhou Tianci, Mitsui Chemicals, Mitsubishi Chemical, etc.

[0100] Average functionality of the initiator

[0101]

[0102] Among them, a1, a2, a n Indicates the functionality of the initiator polyol, M1, M2, M n represents 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 specified in GB / T 265-1988.

[0105] Molecular weight of polyether polyols

[0106] Measurement using GPC

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

[0108] Shore hardness of polishing layer

[0109] Use REX digital display Shaw D automatic hardness tester and Bareiss digital display Shaw D automatic hardness tester for measurement. Punch the sample to be tested into 3"×3" square specimens. The thickness of the sample to be tested is not less than 5mm. The measuring point is at least 9mm away from any edge of the sample. The hardness value on the same sample is measured at least 6mm apart and the maximum value is taken. The sample needs to be tested under a standard environment of 23±2℃ and humidity 50%±10%.

[0110] Density of polishing layer

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

[0112] Polishing performance evaluation of polishing pads

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

[0114] The test machine is AMAT Refelxion (Modify 5Zone);

[0115] The polishing wafer is Cu 10K wafer, the polishing liquid is a diluted solution of ANJI U3061A (10 times) with 1% wtH2O2 added, the flow rate is 230ml / min, the dresser is Saesol's AK53 diamond disk, the pressure is 6lbf, the polishing head pressure is 2.7psi, the platen speed is 77rpm, the carrier speed is 71rpm, and the polishing time is 30s.

[0116] The polishing rate of the 10th wafer and the polishing non-uniformity of 100 wafers were measured.

[0117] Defect evaluation

[0118] The defects on the polished substrate after polishing are obtained using KLA-Tencor The SP2 defect inspection system was used to inspect the defect, and the defect size was 0.16 μm. The 10th wafer was measured.

[0119] Synthesis example 1

[0120] Add 1 mol of mannitol and 0.05 mol of KOH to the reactor under normal pressure, control the temperature at 80°C, and stir for 3 hours; after evacuating, introduce nitrogen to control the pressure in the reactor to 0.3 MPa, then evacuate to 0.095 MPa, repeat three times to maintain the vacuum state; raise the temperature of the reactor to 110°C, add 10 mol of PO in a vacuum state, and after PO reacts completely, evacuate to above 0.095 MPa, and add 2 mol of EO; control the pressure in the reactor to remain unchanged, add 0.2 mol of EO after reacting for 2 hours, react for 0.5 hours, add 0.01 mol of phosphoric acid and distilled water, stir for 30 minutes, dehydrate, and filter to obtain polyether polyol-M1, and the molecular weight of M1 is 11100.

[0121] Synthesis example 2

[0122] Add 1 mol of sorbitol and 0.05 mol of KOH to the reactor under normal pressure, control the temperature at 80°C, and stir for 3 hours; after evacuating, introduce nitrogen to control the pressure in the reactor to 0.3 MPa, then evacuate to 0.095 MPa, repeat three times to maintain the vacuum state; raise the temperature of the reactor to 110°C, add 9.76 mol of PO in a vacuum state, and after PO reacts completely, evacuate to above 0.095 MPa, and add 2.24 mol of EO; control the pressure in the reactor to remain unchanged, add 0.2 mol of EO after reacting for 2 hours, react for 0.5 hours, add 0.01 mol of phosphoric acid and distilled water, stir for 30 minutes, dehydrate, and filter to obtain polyether polyol-M2, and the molecular weight of M2 is 11500.

[0123] Synthesis example 3

[0124] Add 1 mol of glucose and 0.05 mol of KOH to the reactor under normal pressure, control the temperature at 80°C, and stir for 3 hours; after evacuating, introduce nitrogen to control the pressure in the reactor to 0.3 MPa, then evacuate to 0.095 MPa, repeat three times to maintain the vacuum state; raise the temperature of the reactor to 110°C, add 8 mol of PO in a vacuum state, and after PO reacts completely, evacuate to above 0.095 MPa, and add 4 mol of EO; control the pressure in the reactor to remain unchanged, add 0.2 mol of EO after reacting for 2 hours, react for 0.5 hours, then add 0.01 mol of phosphoric acid and distilled water, stir for 30 minutes, dehydrate, and filter to obtain polyether polyol-M3, and the molecular weight of M3 is 11750.

[0125] Synthesis example 4

[0126] Add 1 mol of pentaerythritol and 0.05 mol of KOH to the reactor under normal pressure, control the temperature at 80°C, and stir for 3 hours; after evacuating, introduce nitrogen to control the pressure in the reactor to 0.3 MPa, then evacuate to 0.095 MPa, repeat three times to maintain the vacuum state; raise the temperature of the reactor to 110°C, add 5.33 mol of PO in a vacuum state, and after PO reacts completely, evacuate to above 0.095 MPa, and add 2.67 mol of EO; control the pressure in the reactor to remain unchanged, add 0.2 mol of EO after reacting for 2 hours, react for 0.5 hours, add 0.01 mol of phosphoric acid and distilled water, stir for 30 minutes, dehydrate, and filter to obtain polyether polyol-M4, and the molecular weight of M4 is 8800.

[0127] Synthesis example 5

[0128] Add 1 mol of glycerol and 0.05 mol of KOH to the reactor under normal pressure, control the temperature at 80°C, and stir for 3 hours; after evacuating, introduce nitrogen to control the pressure in the reactor to 0.3 MPa, then evacuate to 0.095 MPa, repeat three times to maintain the vacuum state; raise the temperature of the reactor to 110°C, add 5.83 mol of PO in a vacuum state, and after PO reacts completely, evacuate to above 0.095 MPa, and add 0.17 mol of EO; control the pressure in the reactor to remain unchanged, add 0.2 mol of EO after reacting for 2 hours, react for 0.5 hours, add 0.01 mol of phosphoric acid and distilled water, stir for 30 minutes, dehydrate, and filter to obtain polyether polyol-M5, and the molecular weight of M5 is 7500.

[0129] Synthesis example 6

[0130] Add 1 mol of sucrose and 0.05 mol of KOH to the reactor under normal pressure, control the temperature at 80°C, and stir for 3 hours; after evacuating, introduce nitrogen to control the pressure in the reactor to 0.3 MPa, then evacuate to 0.095 MPa, repeat three times to maintain the vacuum state; raise the temperature of the reactor to 110°C, add 9.01 mol of PO in a vacuum state, and after PO reacts completely, evacuate to above 0.095 MPa, and add 0.99 mol of EO; control the pressure in the reactor to remain unchanged, add 0.2 mol of EO after reacting for 2 hours, react for 0.5 hours, add 0.01 mol of phosphoric acid and distilled water, stir for 30 minutes, dehydrate, and filter to obtain polyether polyol-M6, with a molecular weight of M6 of 9980.

[0131] Synthesis Example 7

[0132] Add 1 mol of sucrose and 0.05 mol of KOH to the reactor under normal pressure, control the temperature at 80°C, and stir for 3 hours; after evacuating, introduce nitrogen to control the pressure in the reactor to 0.3 MPa, then evacuate to 0.095 MPa, repeat three times to maintain the vacuum state; raise the temperature of the reactor to 110°C, add 15.53 mol of PO in a vacuum state, and after PO reacts completely, evacuate to above 0.095 MPa, and add 0.47 mol of EO; control the pressure in the reactor to remain unchanged, add 0.2 mol of EO after reacting for 2 hours, react for 0.5 hours, add 0.01 mol of phosphoric acid and distilled water, stir for 30 minutes, dehydrate, and filter to obtain polyether polyol-M7, and the molecular weight of M7 is 13800.

[0133] Synthesis example 8

[0134] Add 0.74 mol of sucrose, 0.26 mol of glycerol and 0.05 mol of KOH to the reactor under normal pressure, control the temperature at 80°C, and stir for 3 hours; after evacuating, introduce nitrogen to control the pressure in the reactor to 0.3 MPa, then evacuate to 0.095 MPa, repeat three times to maintain the vacuum state; raise the temperature of the reactor to 110°C, add 12.41 mol of PO in a vacuum state, and after PO reacts completely, evacuate to above 0.095 MPa, and add 0.99 mol of EO; control the pressure in the reactor to remain unchanged, add 0.2 mol of EO after reacting for 2 hours, react for 0.5 hours, then add 0.01 mol of phosphoric acid and distilled water, stir for 30 minutes, dehydrate, and filter to obtain polyether polyol-M8, and the molecular weight of M8 is 12100.

[0135] Synthesis example 9

[0136] Add 0.43 mol of sorbitol, 0.67 mol of glycerol and 0.05 mol of KOH to the reactor under normal pressure, control the temperature at 80°C, and stir for 3 hours; after evacuating, introduce nitrogen to control the pressure in the reactor to 0.3 MPa, then evacuate to 0.095 MPa, repeat three times to maintain the vacuum state; raise the temperature of the reactor to 110°C, add 6.32 mol of PO in a vacuum state, and after PO reacts completely, evacuate to above 0.095 MPa, and add 2.28 mol of EO; control the pressure in the reactor to remain unchanged, add 0.2 mol of EO after reacting for 2 hours, react for 0.5 hours, then add 0.01 mol of phosphoric acid and distilled water, stir for 30 minutes, dehydrate, and filter to obtain polyether polyol-M9, and the molecular weight of M9 is 9200.

[0137] Synthesis example 10

[0138] Add 0.2 mol of pentaerythritol, 0.8 mol of xylitol and 0.05 mol of KOH into a reactor under normal pressure, control the temperature at 80°C, and stir for 3 hours; introduce nitrogen after evacuation to control the pressure in the reactor to 0.3 MPa, then evacuate to 0.095 MPa, repeat three times to maintain the vacuum state; raise the temperature of the reactor to 110°C, and add 9.6 mol of EO in a vacuum state; control the pressure in the reactor to remain unchanged, add 0.2 mol of EO after reacting for 2 hours, react for 0.5 hours, add 0.01 mol of phosphoric acid and distilled water, stir for 30 minutes, dehydrate, and filter to obtain polyether polyol-M10, and the molecular weight of M10 is 8900.

[0139] Synthesis example 11

[0140] Add 1 mol of pentaerythritol and 0.05 mol of KOH to a reactor under normal pressure, control the temperature at 80°C, and stir for 3 hours; introduce nitrogen after evacuation to control the pressure in the reactor to 0.3 MPa, then evacuate to 0.095 MPa, repeat three times to maintain the vacuum state; raise the temperature of the reactor to 110°C, add 8 mol of butylene oxide in a vacuum state, and after PO reacts completely, evacuate to above 0.095 MPa, control the pressure in the reactor to remain unchanged, add 0.2 mol of EO after reacting for 2 hours, react for 0.5 hours, then add 0.01 mol of phosphoric acid and distilled water, stir for 30 minutes, dehydrate, and filter to obtain polyether polyol-M11, and the molecular weight of M11 is 8600.

[0141] Synthesis example 12

[0142] Add 1 mol of glucose and 0.05 mol of KOH to the reactor under normal pressure, control the temperature at 80°C, and stir for 3 hours; after evacuating, introduce nitrogen to control the pressure in the reactor to 0.3 MPa, then evacuate to 0.095 MPa, repeat three times to maintain the vacuum state; raise the temperature of the reactor to 110°C, add 5.9 mol of PO in a vacuum state, and after PO reacts completely, evacuate to above 0.095 MPa, and add 6.1 mol of EO; control the pressure in the reactor to remain unchanged, add 0.2 mol of EO after reacting for 2 hours, react for 0.5 hours, then add 0.01 mol of phosphoric acid and distilled water, stir for 30 minutes, dehydrate, and filter to obtain polyether polyol-M12, and the molecular weight of M12 is 11400.

[0143] Synthesis example 13

[0144] Add 1 mol of ethylene glycol and 0.05 mol of KOH to the reactor under normal pressure, control the temperature at 80°C, and stir for 3 hours; after evacuating, introduce nitrogen to control the pressure in the reactor to 0.3 MPa, then evacuate to 0.095 MPa, repeat three times to maintain the vacuum state; raise the temperature of the reactor to 110°C, add 2.65 mol of PO in a vacuum state, and after PO reacts completely, evacuate to above 0.095 MPa, and add 1.35 mol of EO; control the pressure in the reactor to remain unchanged, add 0.2 mol of EO after reacting for 2 hours, react for 0.5 hours, add 0.01 mol of phosphoric acid and distilled water, stir for 30 minutes, dehydrate, and filter to obtain polyether polyol-M13, and the molecular weight of M13 is 6200.

[0145] Synthesis example 14

[0146] Add 0.9 mol of sucrose, 0.1 mol of mannitol and 0.05 mol of KOH to a reactor under normal pressure, control the temperature at 80°C, and stir for 3 hours; introduce nitrogen after evacuation to control the pressure in the reactor to 0.3 MPa, then evacuate to 0.095 MPa, repeat three times to maintain the vacuum state; raise the temperature of the reactor to 110°C, add 13 mol of PO in a vacuum state, and after PO reacts completely, evacuate to above 0.095 MPa, and add 2.6 mol of EO; control the pressure in the reactor to remain unchanged, add 0.2 mol of EO after reacting for 2 hours, react for 0.5 hours, then add 0.01 mol of phosphoric acid and distilled water, stir for 30 minutes, dehydrate, and filter to obtain polyether polyol-M14, and the molecular weight of M14 is 12300.

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

[0148] Table 1

[0149]

[0150] Example 1

[0151] This embodiment provides a polishing pad, and the preparation method is as follows:

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

[0153] Step 2: Keep the curing agent composition: 28.6 parts by mass of MOCA at 115°C and 124.8 parts by mass of polyether polyol M at 25-65°C.

[0154] Step 3: The prepolymer and curing agent composition were mixed under high-speed shearing, and then cast into a circular mold to form a casting block with a thickness of 12 cm, which was left to stand at room temperature for 10 minutes, and then placed in a 100°C oven for curing for 16 hours. After curing, the prepolymer was automatically cooled to room temperature in the oven, and then cut into 80 mil thick sheets, a total of 60 sheets.

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

[0156] Step 5: Use double-sided tape (purchased from Sekisui Chemical Co., Ltd. and 3M Company) for the intermediate glue and the back glue layer, use the intermediate glue to bond the above-mentioned polishing layer and the buffer layer, and bond the back glue layer on the other side of the buffer layer (the side not bonded with the polishing layer) to obtain the polishing pad P1, wherein 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 that the ratio of the polishing layer raw materials is different from that in Example 1, the preparation method is the same as that in Example 1. The ratio of the polishing layer raw materials of Examples 2 to 12 and Comparative Examples 1 to 3 is shown in Table 2.

[0158] Table 2

[0159]

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

[0161] Table 3

[0162]

[0163] It should be noted that, according to the explanation and elaboration of the above description, those skilled in the art to which the present invention belongs may also 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 changes to the present invention should also be within the scope of protection of the claims of the present invention. In addition, although some specific terms are used in this specification, these terms are only for the convenience of description and do not constitute any limitation to the invention.

Claims

1. A polishing pad, characterized in that: A polishing layer having a polished 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 comprises a polyamine and a polyether polyol, 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 the kinematic viscosity at 25°C is 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: In the polyether polyol as shown in Chemical Formula 1, z is between 3 and 8, R represents a 3-8 valent organic group, M represents a 2-valent organic group, and P represents a 1-valent organic group; Preferably, M in the chemical formula 1 represents a structural fragment 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:

3. The polishing pad according to claim 2, characterized in that The molar weight of the structural unit shown in the structural formula 2 is x, and the molar weight of the structural unit shown in the structural formula 3 is y, wherein x / y is between 0.03 and 1, preferably, x / y is between 0.03 and 0.5; particularly preferably, x / y is between 0.08 and 0.

3.

4. The polishing pad according to claim 2, characterized in that In the polyether polyol chemical formula 1, P represents a hydrogen atom or a structural unit as shown in structural formula 4; preferably, in the polyether polyol chemical formula 1, P represents a structural unit as shown in structural formula 4:

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

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

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

7.

8. 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.

9. The polishing pad according to claim 1, characterized in that The molecular weight Mw of the polyether polyol is between 7000 and 12000; preferably, the molecular weight Mw of the polyether polyol is between 9500 and 12000.

10. The polishing pad according to claim 1, wherein: 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.

11. The polishing pad according to claim 1, wherein: The density of the polishing layer is between 0.7 g / cm 3 ~0.9g / cm 3 The hardness of the polishing layer is between 50D and 63D.

12. A polishing method, characterized in that: A substrate is provided, wherein the substrate is selected from at least one of a magnetic substrate, an optical substrate or a semiconductor substrate, a polishing pad as described in any one of claims 1 to 11 is provided, dynamic contact is formed between the polishing surface of the polishing layer and the substrate to polish the surface of the substrate, and an abrasive dresser is used to dress the polishing surface.

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