Polishing layer, polishing pad and manufacturing method of semiconductor device

Abstract

The present invention relates to a polishing layer comprising a closed-cell elastomer formed by separating a continuous polyurethane substrate comprising the reaction product of an isocyanate-terminated prepolymer and a curing agent by pores of 5-100 [mu] m in size; the polishing layer comprises a polishing surface, a ball with the mass of m and the diameter of L is freely released at the position h above the polishing surface, the height h1 from the bottom of the metal ball to the polishing surface is the moment when the ball makes contact with the polishing surface and the metal ball bounces upwards till the linear speed is equal to 0, and when h ranges from 490 mm to 520 mm, the mass m of the ball ranges from 15 g to 19 g, and the diameter L of the ball ranges from 15 mm to 17 mm, h1 is the height h1, and h2 is the height h1. The loss height h2 is equal to h-h1-L, and the loss height h2 is between 280 mm and 440 mm; the polishing layer is controlled to be within the range, the prepared polishing pad shows good polishing performance, the TEOS removal rate is high, the grinding rate non-uniformity is low, the Defect is few, and the comprehensive performance is excellent.

Description

Technical Field

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

[0002] Chemical mechanical polishing is a conventional technique for planarizing or polishing workpieces such as semiconductor wafers. In conventional CMP, a wafer carrier or polishing head is mounted in a carrier assembly, the polishing head clamps the wafer and positions the wafer in contact with the polishing layer of a polishing pad, and the polishing pad is mounted on a workbench or platen in a CMP device. The carrier assembly provides a controllable pressure between the wafer and the polishing pad. At the same time, a polishing medium (such as a polishing slurry) is dispensed onto the polishing pad and is sucked into the pores between the wafer and the polishing layer. To achieve polishing, the polishing pad and the wafer are usually rotated relative to each other. When the polishing pad rotates under the wafer, the wafer sweeps out a polishing track or polishing area that is usually annular, in which the wafer surface is directly opposite to the polishing layer. Through the polishing layer and the polishing medium on the surface and the chemical mechanical action, the wafer surface is polished and becomes flat.

[0003] Semiconductor devices are becoming more and more complex, with finer structural units and more metallization layers. There is an urgent need to improve the performance of polishing pads to maintain flatness and limit polishing defects. The rebound performance of polishing pads affects critical properties such as RR and the number of defects. Polishing pads are usually made of polyurethane materials. How to control the rebound performance of polishing pads through formula design to obtain polishing pads with better performance is a problem that needs to be solved urgently in the existing technology. Summary of the invention

[0004] In order to solve the problems existing in the prior art, the first aspect of the present invention provides a polishing layer, the polishing layer comprises a closed-cell elastomer formed by a continuous polyurethane substrate separated by pores of 5 to 100 μm, the polyurethane substrate comprises a reaction product of a prepolymer terminated by isocyanate and a curing agent; the polishing layer comprises a polishing surface, a sphere with a mass of m and a diameter of L is freely released at a distance h above the polishing surface, the height from the bottom of the metal ball to the polishing surface when the sphere contacts the polishing surface to the moment when the metal ball rebounds upward to a linear velocity equal to 0 is h1, when h is between 490 mm and 520 mm, the mass m of the sphere is between 15 g and 19 g, and the diameter L of the sphere is between 15 mm and 17 mm, wherein the loss height h2=h-h1-L, and the loss height h2 is between 280 mm and 440 mm;

[0005] Furthermore, the thickness of the polishing layer is between 50 mil and 120 mil;

[0006] Furthermore, the density of the polishing layer is between 0.4 g / cm3 ~1.1g / cm 3 ;

[0007] Preferably, the density of the polishing layer is between 0.5 g / cm 3 ~1.05g / cm 3 ;

[0008] Particularly preferably, the density of the polishing layer is between 0.6 g / cm 3 ~1.0g / cm 3 ;

[0009] Further, the isocyanate-terminated prepolymer comprises a reaction product of a multifunctional isocyanate and a polyol;

[0010] Further, the multifunctional isocyanate comprises 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-phenylene diisocyanate, m-phenylene diisocyanate, ethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 1,6-hexamethylene diisocyanate, 1,4-cyclohexane diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, isophorone diisocyanate, and norbornane diisocyanate;

[0011] Preferably, the multifunctional isocyanate comprises one or more combinations of 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, and 4,4'-dicyclohexylmethane diisocyanate;

[0012] Further, the polyol comprises one or more combinations of polytetramethylene ether glycol, polyethylene glycol, polypropylene glycol, ethylene glycol, butanediol, diethylene glycol, neopentyl glycol, 2-methyl-1,3-propanediol, hexanediol, 3-methyl-1,5-pentanediol, 1,4-cyclohexanedimethanol, homopolymers and / or copolymers of ethylene oxide and propylene oxide;

[0013] Preferably, the polyol comprises one or more combinations of polytetramethylene ether glycol, polypropylene glycol, diethylene glycol, homopolymers and / or copolymers of ethylene oxide and propylene oxide;

[0014] Further, the curing agent comprises a polyamine curing agent or a polyol curing agent;

[0015] Further, the polyamine curing agent includes diethyltoluenediamine (DETDA), N,N'-dialkyldiaminodiphenylmethane, 3,5-diethyl-2,4-toluenediamine and its isomers (for example, 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) (MCDEA), polyoxytetramethylene-di-p-aminobenzoate; p,p'-methylenedianiline (MDA); metaphenylenediamine (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;

[0016] Preferably, the polyamine curing agent is 4,4'-methylene-bis-(2-chloroaniline) (MOCA);

[0017] Further, the polyol curing agent has a number average molecular weight of 2000 to 100000, and the polyol curing agent has an average of 3 to 30 hydroxyl groups;

[0018] Preferably, the polyol curing agent contains 4 to 8 hydroxyl groups;

[0019] Further, the unreacted NCO of the isocyanate-terminated prepolymer is between 8.0% and 9.5%, and the stoichiometric ratio of the NH2 from the curing agent to the NCO of the isocyanate-terminated prepolymer is between 80% and 105%;

[0020] A second aspect of the present invention provides a polishing pad for chemical mechanical polishing of at least one substrate selected from a magnetic substrate, an optical substrate and a semiconductor substrate, wherein the polishing pad comprises the polishing layer as described above.

[0021] A third aspect of the present invention provides a polishing pad for chemical mechanical polishing of at least one substrate selected from a magnetic substrate, an optical substrate and a semiconductor substrate, wherein the resilience of the polishing pad is between 5% and 40%;

[0022] Furthermore, the polishing pad comprises a polishing layer, an intermediate adhesive layer, a buffer layer and a release film layer.

[0023] A fourth aspect of the present invention provides a method for manufacturing a semiconductor device, providing a semiconductor device, wherein the semiconductor device comprises a substrate, wherein the substrate is selected from at least one of a magnetic substrate, an optical substrate or a semiconductor substrate, providing the above-mentioned polishing pad, forming 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 dress the polishing surface.

[0024] Beneficial Effects

[0025] The present invention adjusts the resilience of the polyurethane material by controlling the formula of the polyurethane, so that the resilience of the prepared polishing layer and the polishing pad is within a certain range, and the polishing pad exhibits good polishing performance, including a higher TEOS removal rate, lower grinding rate non-uniformity and fewer defects, and has excellent comprehensive performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] 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.

[0027] Figure 1 A schematic diagram of a polishing operation process performed by a polishing pad according to an embodiment of the present invention;

[0028] Figure 2 A schematic diagram of a polishing pad provided for an embodiment of the present invention;

[0029] Figure 3 It is a schematic diagram of the original state of the device for measuring the loss height h2 and the rebound performance in the embodiment of the present invention;

[0030] Figure 4 It is a schematic diagram of the measuring state of the device for measuring the loss height h2 and the rebound performance in the embodiment of the present invention;

[0031] 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

[0032] A polishing layer is provided in an embodiment of the present invention, wherein the polishing layer comprises a closed-cell elastomer formed by a continuous polyurethane substrate separated by pores of 5 to 100 μm. The polyurethane substrate in the embodiment of the present invention comprises a reaction product of an isocyanate-terminated prepolymer and a curing agent. Optionally, the polyurethane substrate in the embodiment of the present invention can also be achieved using a one-step synthesis method, that is, using a multifunctional isocyanate, a polyol and a curing agent to directly react to obtain it; preferably, in the embodiment of the present invention, a prepolymer method is selected for synthesis using an isocyanate-terminated prepolymer and a curing agent to react.

[0033] The polishing layer in the embodiment of the present invention includes a polishing surface, a sphere with a mass m and a diameter L freely released at a distance h above the polishing surface, the height from the bottom of the metal ball to the polishing surface when the sphere contacts the polishing surface until the metal ball rebounds upward to the moment when the linear velocity is equal to 0 is h1, when h is between 490mm and 520mm, the mass m of the sphere is between 15g and 19g, and the diameter L of the sphere is between 15mm and 17mm, wherein the loss height h2=h-h1-L, and the loss height h2 is between 280mm and 440mm.

[0034] In the embodiment of the present invention, the loss height h2 is a parameter of the rebound performance of the reaction polishing layer. The specific test equipment can be referred to. The above test conditions are preferably: the release height h is 500mm, the metal ball is a steel ball, the mass m is 16.8±1.5g, and the diameter L is 16mm.

[0035] In the embodiment of the present invention, the thickness of the polishing layer is between 50 mil and 120 mil, preferably, the thickness of the polishing layer is between 50 mil and 100 mil, and particularly preferably, the thickness of the polishing layer is between 50 mil and 80 mil.

[0036] The density of the polishing layer in the embodiment of the present invention is between 0.4 g / cm 3 ~1.1g / cm 3 Preferably, the density of the polishing layer is between 0.5 g / cm 3 ~1.05g / cm 3 , particularly preferably, the density of the polishing layer is between 0.6 g / cm 3 ~1.0g / cm 3 .

[0037] The isocyanate-terminated prepolymer in the embodiment of the present invention comprises a reaction product of a multifunctional isocyanate and a polyol.

[0038] Multifunctional isocyanate

[0039] In the embodiment of the present invention, the polyfunctional isocyanate 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, more preferably more than 95 mol % of aromatic isocyanates, and particularly preferably 100 mol % of aromatic isocyanates.

[0040] The aromatic isocyanate includes one or more combinations of toluene diisocyanate, diphenylmethane diisocyanate, 1,5-naphthalene diisocyanate, p-phenylene diisocyanate, m-phenylene diisocyanate, p-xylylene diisocyanate, and m-xylylene diisocyanate.

[0041] 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.

[0042] In the embodiment of the present invention, in consideration of the reaction activity and the physical properties of the polishing pad, one or more combinations of toluene diisocyanate, diphenylmethane diisocyanate, and 4,4'-dicyclohexylmethane diisocyanate are preferably used.

[0043] In the embodiment of the present invention, considering the reaction activity and the physical properties of the polishing pad, it is particularly preferred to use one or a combination of toluene diisocyanate and 4,4-dicyclohexylmethane diisocyanate, wherein the toluene diisocyanate may include one or a combination of 2,4-toluene diisocyanate or 2,6-toluene diisocyanate.

[0044] Polyols

[0045] In the embodiment of the present invention, the polyol may include a high molecular weight diol based on polyether, wherein the high molecular weight diol based on polyether includes 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, homopolymers and / or copolymers of ethylene oxide and propylene oxide, 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.

[0046] In the embodiment of the present invention, the polyol may include a small molecule diol, wherein the small molecule includes but is not limited to one or more combinations of ethylene glycol, butanediol, diethylene glycol, neopentyl glycol, 2-methyl-1,3-propanediol, hexanediol, 3-methyl-1,5-pentanediol, and 1,4-cyclohexanedimethanol.

[0047] In the embodiment of the present invention, the polyol composition may further include a polyester-based polyol, wherein the polyester-based polyol is obtained by a condensation reaction of a diol or a diol / phenol with a dibasic acid, wherein the diol includes ethylene glycol, 1,3-butanediol, 1,4-butanediol, diethylene glycol, neopentyl glycol, 2-methyl-1,3-propanediol, hexanediol, 3-methyl-1,5-pentanediol, 1,4-cyclohexanedimethanol, or one or more combinations thereof. Preferably, the diol includes 1,4-butanediol, one or a combination of hexanediol; the diol / phenol is one or a combination of hydroquinone, resorcinol, naphthalene diol, bisphenol A, bisphenol S, terephthalic acid, isophthalic acid, o-phthalic acid, 2,5-furan dimethanol, terephthalic acid or diphenyl ether diphenol. Preferably, the diol / phenol is one or a combination of hydroquinone and terephthalic acid; the dibasic acid is one or a combination of succinic acid, adipic acid, azelaic acid and sebacic acid.

[0048] In the embodiment of the present invention, considering the reactivity and physical properties of the polishing pad, one or more combinations of polytetramethylene ether glycol (PTMEG), diethylene glycol, butanediol or homopolymers and / or copolymers of ethylene oxide and propylene oxide are preferably used.

[0049] In the embodiments of the present invention, considering the reactivity and physical properties of the polishing pad, it is particularly preferred to use one of polytetramethylene ether glycol (PTMEG) and diethylene glycol or a combination of the two.

[0050] The isocyanate-terminated prepolymer can be obtained by reacting the multifunctional isocyanate with a polyol, or by purchasing a commercially available prepolymer product.

[0051] Commercially available isocyanate-terminated prepolymers include, but are not limited to, any one or more combinations of the series of prepolymers produced by Chemtura: LF800A, LF900A, LF910A, LF930A, LF931A, LF939A, LF950A, LF952A, LF600D, LF601D, LF650D, L42, L325, L100, L150, L167, L200, L275, L300, L310, L367, L480, L500, LF667, LF667D, LF700D, LF750D, LF751D, LF752D, LF753D, LFG963A, LFG964A, and LFG740D.

[0052] Curing agent

[0053] In the embodiment of the present invention, the curing agent is selected from one or more combinations of polyamine curing agents or polyol curing agents. The present invention has no particular limitation on the polyamine curing agent or the polyol curing agent, and can be any suitable aromatic bifunctional curing agent or polyol curing agent in the art.

[0054] Examples of polyamine curing agents that can be used in embodiments of the present invention include 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'- One or more combinations of methylene-bis-(3-chloro-2,6-diethylaniline) (M-CDEA), polyoxytetramethylene-di-p-aminobenzoate; p,p'-methylenedianiline (MDA); metaphenylenediamine (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.

[0055] Taking into account the unique chemical structure of MOCA, in order to ensure that the polishing pad has a suitable operating time during preparation and the resulting polishing pad has good polishing performance, preferably, the polyamine curing agent contains one or a combination of 4,4'-methylene-bis-(2-chloroaniline) (MOCA) and 4,4'-methylene-bis-(3-chloro-2,6-diethylaniline) (M-CDEA); particularly preferably, the polyamine curing agent contains 4,4'-methylene-bis-(2-chloroaniline) (MOCA).

[0056] Optionally, the polyol curing agent in the embodiment of the present invention can also be a high molecular weight polyol curing agent, the high molecular weight polyol curing agent has a number average molecular weight of 2000 to 100000, and the high molecular weight polyol curing agent has an average of 3 to 30 hydroxyl groups. Preferably, the high molecular weight polyol contains 4 to 8 hydroxyl groups; commercially available high molecular weight polyols can be selected Polyols, Polyols and Polyols of the polyol series (from Dow Chemical). Preferably, the embodiments of the present invention include a combination of a polyamine curing agent and a high molecular weight polyol curing agent, and particularly preferably, the embodiments of the present invention only include a polyamine curing agent.

[0057] Hollow microsphere polymer

[0058] 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.

[0059] 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 increase 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%.

[0060] 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.

[0061] In the embodiment of the present invention, the unreacted NCO content of the isocyanate-terminated prepolymer is between 8.0% and 9.5%. Preferably, the unreacted NCO content of the isocyanate-terminated prepolymer is between 8.5% and 9.5%.

[0062] In the embodiment of the present invention, the stoichiometric ratio of NCO of the isocyanate-terminated prepolymer of NH2 and / or OH in the curing agent is between 80% and 105%; preferably, the stoichiometric ratio of NCO of the isocyanate-terminated prepolymer of NH2 and / or OH in the curing agent is between 80% and 100%.

[0063] The resilience of the polishing pad in the embodiment of the present invention is between 5% and 40%. Figure 2 The polishing pad shown includes a polishing layer 20 , an intermediate adhesive layer 21 , a buffer layer 22 and a release film layer 23 .

[0064] In the present invention, appropriate modifiers may be added to the polyurethane substrate to obtain more excellent comprehensive performance improvement. Preferably, these modifiers can change at least one property of the polishing layer, and the above properties include but are not limited to the group consisting of the following items: porosity, rigidity, surface energy, wear resistance, conductivity, and chemical function. Modified materials include but are not limited to: antioxidants, lubricants, pigments, fillers, antistatic agents, etc.

[0065] In 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 layer 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 of concentric grooves (for example, annular or spiral grooves), curved grooves, grid line grooves, regular polygonal grooves (for example, hexagonal, triangular), and tire surface patterns. Particularly preferably, the grooves are one or more of annular grooves, spiral grooves, X-Y grid grooves, hexagonal grooves, triangular grooves and fractal grooves. Particularly preferably, the cross-section of the groove is one or more of a straight sidewall rectangle, a "V" shape, a "U" shape and a zigzag shape.

[0066] Optionally, the width of the groove is 0.1-0.6 mm, the depth of the groove is 0.5-0.9 mm, the spacing between adjacent grooves is 2-5 mm, a central blank area may be provided or not provided, wherein the radius of the central blank area is 50 mm-150 mm.

[0067] In CMP, a buffer layer is required to take into account both planarity and uniformity, which are in a compromise relationship. Planarity refers to the flatness of the pattern portion when polishing a polished material having micro-concave and convex portions generated during pattern formation, and uniformity refers to the uniformity of the entire polished material. The planarity is improved by utilizing the characteristics of the polishing layer, and the uniformity is improved by utilizing the characteristics of the buffer layer. In the polishing pad of the present invention, the buffer layer is preferably made of a material softer than the polishing layer.

[0068] Examples of the cushioning layer include fiber nonwoven fabrics such as polyester nonwoven fabrics, nylon nonwoven fabrics, and acrylonitrile nonwoven fabrics, resin impregnated nonwoven fabrics such as polyester nonwoven fabrics impregnated with polyurethane, polymer resin foams such as polyurethane foam and polyethylene foam, rubber resins such as butadiene rubber and isoprene rubber, and photosensitive resins.

[0069] As a method for bonding the polishing layer and the buffer layer, an intermediate glue is used. The intermediate glue can be a double-sided tape. The polishing layer and the buffer layer are placed on both sides of the intermediate glue for pressing.

[0070] The polishing pad of the present invention also includes a back adhesive layer, and a double-sided tape can be used as the back adhesive layer. As the composition of the back adhesive layer, for example, a rubber adhesive, an acrylic adhesive, etc. can be listed. Considering the content of metal ions, acrylic adhesives have less metal ion content, so they are preferred.

[0071] The adhesive layer in the present invention further comprises a release film or a release paper, and the release film or the release paper can be torn off before use to achieve the bonding of the polishing pad and the polishing machine.

[0072] The polishing layer in the embodiment of the present invention may be provided with an endpoint detection window according to actual needs. Optionally, at least one endpoint detection area may be formed in the polishing layer. When the polishing operation is performed, the endpoint detection area of ​​the polishing layer can perform high-precision optical endpoint detection, and the detection method may be optical detection. The endpoint detection area is made of a suitable material so that it has a suitable light transmittance to observe the polished object (such as a silicon wafer). As a preferred embodiment, the material forming the endpoint detection area has a light transmittance of not less than 20% in the entire range of wavelengths of 300 to 800. More preferably, the light transmittance of the high-transmittance material is not less than 60%.

[0073] As a preferred embodiment, the material of the endpoint detection area includes but is not limited to thermosetting resins such as polyurethane resin, polyester resin, phenol resin, urea resin, melamine resin, epoxy resin and acrylic resin; one or more combinations of polyurethane resin, polyester resin, polyamide resin, cellulose resin, acrylic resin, polycarbonate resin, halogen-containing resin (polyvinyl chloride, polytetrafluoroethylene and polyvinylidene fluoride, etc.), polystyrene and olefin resin (polyethylene, polypropylene, etc.) thermoplastic resins.

[0074] <Polishing>

[0075] 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.

[0076] Polishing: Use Figure 1 The 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.

[0077] Example

[0078] 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.

[0079] Explanation of the reference numerals in the embodiments:

[0080] L325, LF750D, LFG963A, LF667: respectively L325 isocyanate terminated prepolymer; LF750D isocyanate terminated prepolymer; LFG963A isocyanate terminated prepolymer; LF667 isocyanate terminated prepolymer;

[0081] MOCA: 4,4'-methylene-bis-(2-chloroaniline);

[0082] DEG: diethylene glycol;

[0083] TDI: toluene diisocyanate;

[0084] HMDI: 4,4'-dicyclohexylmethane diisocyanate;

[0085] PTMEG: polytetramethylene ether glycol;

[0086] 800: polyol purchased from Dow Chemical Company, functionality 4, molecular weight 280;

[0087] HF505: polyol purchased from Dow Chemical Company, functionality 6, molecular weight 11400;

[0088] 920DE 40d30: Nouryon 920DE 40d30, average particle size 40μm, density 0.03g / cm 3 ;

[0089] 920DET 40d25: Nouryon 920DET 40d25, average particle size 40μm, density 0.025g / cm 3 ;

[0090] 920DE 80d30: Nouryon 920DE 80d30, average particle size 80μm, density 0.03g / cm 3 ;

[0091] 043DET 80d20: Nouryon 043DET 80d20, average particle size 80μm, density 0.02g / cm 3 ;

[0092] 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.

[0093] Example 1

[0094] This embodiment provides a polishing pad, and the preparation method thereof is as follows:

[0095] Step 1: Take 37.79 parts by mass of TDI, 1.22 parts by mass of HMDI, 55.08 parts by mass of PTMEG1000 and 5.92 parts by mass of DEG to react to obtain an isocyanate-terminated prepolymer, heat to 25-65°C, and degas for 2 hours under vacuum (-0.095MPa) to remove the gas and small molecular compounds in the prepolymer; then add 1.34 parts by mass of hollow microsphere polymer 920DE 40d30, stir to make the hollow microsphere polymer uniformly dispersed in the prepolymer, degas again under vacuum (-0.095MPa) for 2 hours, and set aside. The unreacted NCO in the isocyanate-terminated prepolymer is 9.31%.

[0096] Step 2: 25.75 parts by mass of MOCA was heated to 115° C. for standby use, wherein the stoichiometric ratio of NH2 in MOCA to NCO of the isocyanate-terminated prepolymer was 87%.

[0097] Step 3: Mix the prepolymer and curing agent under high-speed shearing, then cast into a round mold to form a casting block with a thickness of 12 cm, let it stand at room temperature for 10 minutes, and then place it in a 100°C oven for curing for 16 hours. After curing, it is automatically cooled to room temperature in the oven and then cut into sheets with thicknesses of 80 mil, 50 mil, and 120 mil.

[0098] Step 4: Select a thin sheet with a thickness of 80 mils. The groove shape uses concentric grooves with a blank (ungrooved) area in the center. The groove parameters are: groove depth 30 mils, groove width 20 mils, groove spacing 120 mils, and the diameter of the center blank area is 5 inches. After grooving, it becomes a polishing layer.

[0099] 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.).

[0100] Example 2

[0101] This embodiment provides a polishing pad, and the preparation method thereof is as follows:

[0102] Step 1: Take 32.65 parts by mass of TDI, 8 parts by mass of HMDI, 57.25 parts by mass of PTMEG650 and 2.10 parts by mass of DEG to react to obtain an isocyanate-terminated prepolymer, heat to 25-65°C, and degas for 2 hours under vacuum (-0.095MPa) to remove the gas and small molecular compounds in the prepolymer; then add 1.96 parts by mass of hollow microsphere polymer 920DE 40d30, stir to make the hollow microsphere polymer uniformly dispersed in the prepolymer, degas again under vacuum (-0.095MPa) for 2 hours, and set aside. The unreacted NCO in the isocyanate-terminated prepolymer is 9.25%.

[0103] Step 2: 25.58 parts by mass of MOCA was heated to 115° C. for standby use, wherein the stoichiometric ratio of NH2 in MOCA to NCO of the isocyanate-terminated prepolymer was 87%.

[0104] Step 3: Mix the prepolymer and curing agent under high-speed shearing, then cast into a round mold to form a casting block with a thickness of 12 cm, let it stand at room temperature for 10 minutes, and then place it in a 100°C oven for curing for 16 hours. After curing, it is automatically cooled to room temperature in the oven and then cut into sheets with thicknesses of 80 mil, 50 mil, and 120 mil.

[0105] Step 4: Select a thin sheet with a thickness of 80 mils. The groove shape uses concentric grooves with a blank (ungrooved) area in the center. The groove parameters are: groove depth 30 mils, groove width 20 mils, groove spacing 120 mils, and the diameter of the center blank area is 5 inches. After grooving, it becomes a polishing layer.

[0106] 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 P2, wherein the buffer layer uses polyurethane impregnated non-woven fabric material Z70 (purchased from Dinglong Co., Ltd.).

[0107] Example 3

[0108] This embodiment provides a polishing pad, and the preparation method thereof is as follows:

[0109] Step 1: Take 32.65 parts by mass of TDI, 8 parts by mass of HMDI, 57.25 parts by mass of PTMEG650 and 2.10 parts by mass of DEG to react to obtain an isocyanate-terminated prepolymer, heat to 25-65°C, and degas for 2 hours under vacuum (-0.095MPa) to remove the gas and small molecular compounds in the prepolymer; then add 3.61 parts by mass of hollow microsphere polymer 920DET 40d25, stir to make the hollow microsphere polymer uniformly dispersed in the prepolymer, degas again under vacuum (-0.095MPa) for 2 hours, and set aside. The unreacted NCO in the isocyanate-terminated prepolymer is 9.25%.

[0110] Step 2: 25.58 parts by mass of MOCA was heated to 115° C. for standby use, wherein the stoichiometric ratio of NH2 in MOCA to NCO of the isocyanate-terminated prepolymer was 87%.

[0111] Step 3: Mix the prepolymer and curing agent under high-speed shearing, then cast into a round mold to form a casting block with a thickness of 12 cm, let it stand at room temperature for 10 minutes, and then place it in a 100°C oven for curing for 16 hours. After curing, it is automatically cooled to room temperature in the oven and then cut into sheets with thicknesses of 80 mil, 50 mil, and 120 mil.

[0112] Step 4: Select a thin sheet with a thickness of 80 mils. The groove shape uses concentric grooves with a blank (ungrooved) area in the center. The groove parameters are: groove depth 30 mils, groove width 20 mils, groove spacing 120 mils, and the diameter of the center blank area is 5 inches. After grooving, it becomes a polishing layer.

[0113] 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 P3, wherein the buffer layer uses polyurethane impregnated non-woven fabric material Z70 (purchased from Dinglong Co., Ltd.).

[0114] Example 4

[0115] This embodiment provides a polishing pad, and the preparation method thereof is as follows:

[0116] Step 1: Take 37.79 parts by mass of TDI, 1.22 parts by mass of HMDI, 55.08 parts by mass of PTMEG1000 and 5.92 parts by mass of DEG to react to obtain an isocyanate-terminated prepolymer, heat to 25-65°C, and degas for 2 hours under vacuum (-0.095MPa) to remove the gas and small molecular compounds in the prepolymer; then add 1.28 parts by mass of hollow microsphere polymer 920DE 80d30, stir to make the hollow microsphere polymer uniformly dispersed in the prepolymer, degas again under vacuum (-0.095MPa) for 2 hours, and set aside. The unreacted NCO in the isocyanate-terminated prepolymer is 9.31%.

[0117] Step 2: 25.75 parts by mass of MOCA was heated to 115° C. for standby use, wherein the stoichiometric ratio of NH2 in MOCA to NCO of the isocyanate-terminated prepolymer was 87%.

[0118] Step 3: Mix the prepolymer and curing agent under high-speed shearing, then cast into a round mold to form a casting block with a thickness of 12 cm, let it stand at room temperature for 10 minutes, and then place it in a 100°C oven for curing for 16 hours. After curing, it is automatically cooled to room temperature in the oven and then cut into sheets with thicknesses of 80 mil, 50 mil, and 120 mil.

[0119] Step 4: Select a thin sheet with a thickness of 80 mils. The groove shape uses concentric grooves with a blank (ungrooved) area in the center. The groove parameters are: groove depth 30 mils, groove width 20 mils, groove spacing 120 mils, and the diameter of the center blank area is 5 inches. After grooving, it becomes a polishing layer.

[0120] 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 P4, wherein the buffer layer uses polyurethane impregnated non-woven fabric material Z70 (purchased from Dinglong Co., Ltd.).

[0121] Example 5

[0122] This embodiment provides a polishing pad, and the preparation method thereof is as follows:

[0123] Step 1: Take 32.65 parts by mass of TDI, 8 parts by mass of HMDI, 57.25 parts by mass of PTMEG650 and 2.10 parts by mass of DEG to react to obtain an isocyanate-terminated prepolymer, heat to 25-65°C, and degas for 2 hours under vacuum (-0.095MPa) to remove the gas and small molecular compounds in the prepolymer; then add 0.83 parts by mass of hollow microsphere polymer 043DET 80d20, stir to make the hollow microsphere polymer uniformly dispersed in the prepolymer, degas again under vacuum (-0.095MPa) for 2 hours, and set aside. The unreacted NCO in the isocyanate-terminated prepolymer is 9.25%.

[0124] Step 2: 30.87 parts by mass of MOCA was heated to 115° C. for standby use, wherein the stoichiometric ratio of NH2 in MOCA to NCO of the isocyanate-terminated prepolymer was 105%.

[0125] Step 3: Mix the prepolymer and curing agent under high-speed shearing, then cast into a round mold to form a casting block with a thickness of 12 cm, let it stand at room temperature for 10 minutes, and then place it in a 100°C oven for curing for 16 hours. After curing, it is automatically cooled to room temperature in the oven and then cut into sheets with thicknesses of 80 mil, 50 mil, and 120 mil.

[0126] Step 4: Select a thin sheet with a thickness of 80 mils. The groove shape uses concentric grooves with a blank (ungrooved) area in the center. The groove parameters are: groove depth 30 mils, groove width 20 mils, groove spacing 120 mils, and the diameter of the center blank area is 5 inches. After grooving, it becomes a polishing layer.

[0127] 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 P5, wherein the buffer layer uses polyurethane impregnated non-woven fabric material Z70 (purchased from Dinglong Co., Ltd.).

[0128] Example 6

[0129] This embodiment provides a polishing pad, and the preparation method thereof is as follows:

[0130] Step 1: Take 39.01 parts by mass of TDI, 55.08 parts by mass of PTMEG1000 and 5.91 parts by mass of DEG to react to obtain an isocyanate-terminated prepolymer, heat to 25-65°C, and degas for 2 hours under vacuum (-0.095MPa) to remove the gas and small molecular compounds in the prepolymer; then add 0.32 parts by mass of hollow microsphere polymer 920DE40d30, stir to make the hollow microsphere polymer uniformly dispersed in the prepolymer, degas again under vacuum (-0.095MPa) for 2 hours, and set aside. The unreacted NCO in the isocyanate-terminated prepolymer is 8.90%.

[0131] Step 2: 29.72 parts by mass of MOCA was heated to 115° C. for standby use, wherein the stoichiometric ratio of NH2 in MOCA to NCO of the isocyanate-terminated prepolymer was 105%.

[0132] Step 3: Mix the prepolymer and curing agent under high-speed shearing, then cast into a round mold to form a casting block with a thickness of 12 cm, let it stand at room temperature for 10 minutes, and then place it in a 100°C oven for curing for 16 hours. After curing, it is automatically cooled to room temperature in the oven and then cut into sheets with thicknesses of 80 mil, 50 mil, and 120 mil.

[0133] Step 4: Select a thin sheet with a thickness of 80 mils. The groove shape uses concentric grooves with a blank (ungrooved) area in the center. The groove parameters are: groove depth 30 mils, groove width 20 mils, groove spacing 120 mils, and the diameter of the center blank area is 5 inches. After grooving, it becomes a polishing layer.

[0134] 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 P6, wherein the buffer layer uses polyurethane impregnated non-woven fabric material Z70 (purchased from Dinglong Co., Ltd.).

[0135] Example 7

[0136] This embodiment provides a polishing pad, and the preparation method is as follows:

[0137] 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 1.07 parts by mass of hollow microsphere polymer 920 DE 40 d30, stir to make the hollow microsphere polymer uniformly dispersed in the prepolymer, degas again under vacuum (-0.095MPa) for 2h, and set aside. The unreacted NCO in the isocyanate-terminated prepolymer is 9.25%.

[0138] Step 2: Mix the curing agent composition: 28.6 parts by mass of MOCA at 115°C and polyether polyol 31.7 parts by mass of HF505 (molecular weight 11400) was maintained at 25-65° C. The stoichiometric ratio of the sum of NH2 in MOCA and OH in polyether polyol to NCO in the isocyanate-terminated prepolymer was 105%.

[0139] 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 sheets with thicknesses of 80 mil, 50 mil, and 120 mil.

[0140] Step 4: Select a thin sheet with a thickness of 80 mils. The groove shape uses concentric grooves with a blank (ungrooved) area in the center. The groove parameters are: groove depth 30 mils, groove width 20 mils, groove spacing 120 mils, and the diameter of the center blank area is 5 inches. After grooving, it becomes a polishing layer.

[0141] 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 P7, wherein the buffer layer uses polyurethane impregnated non-woven fabric material Z70 (purchased from Dinglong Co., Ltd.).

[0142] Example 8

[0143] This embodiment provides a polishing pad, and the preparation method is as follows:

[0144] Step 1: Take 78 parts by mass LF750D isocyanate-terminated prepolymer and 22 parts by mass of The LFG963A isocyanate-terminated prepolymer was mixed, heated to 25-65°C, degassed under vacuum (-0.095MPa) for 2h, and then 0.55 parts by mass of hollow microsphere polymer 920 DE 40 d30 was added, and the hollow microsphere polymer was uniformly dispersed in the prepolymer under stirring, and degassed again under vacuum (-0.095MPa) for 2h for standby use. The unreacted NCO in the isocyanate-terminated prepolymer was 8.3%.

[0145] Step 2: Keep the curing agent composition: 23.49 parts by mass of MOCA at 115° C. for standby use, wherein the stoichiometric ratio of NH2 in MOCA to NCO in the isocyanate-terminated prepolymer is 89%.

[0146] 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 sheets with thicknesses of 80 mil, 50 mil, and 120 mil.

[0147] Step 4: Select a thin sheet with a thickness of 80 mils. The groove shape uses concentric grooves with a blank (ungrooved) area in the center. The groove parameters are: groove depth 30 mils, groove width 20 mils, groove spacing 120 mils, and the diameter of the center blank area is 5 inches. After grooving, it becomes a polishing layer.

[0148] 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 P8, wherein the buffer layer uses polyurethane impregnated non-woven fabric material Z70 (purchased from Dinglong Co., Ltd.).

[0149] Comparative Example 1

[0150] This comparative example provides a polishing pad, and the preparation method is as follows:

[0151] Step 1: Take 100 parts by mass LFG963A isocyanate-terminated prepolymer was heated to 25-65°C, degassed under vacuum (-0.095 MPa) for 2 hours, and then 1.61 parts by mass of hollow microsphere polymer 920DE 40d30 was added, and the hollow microsphere polymer was uniformly dispersed in the prepolymer under stirring, and degassed again under vacuum (-0.095 MPa) for 2 hours for standby use. The unreacted NCO in the isocyanate-terminated prepolymer was 5.8%.

[0152] Step 2: Mix the curing agent composition: MOCA 7.07 parts by mass at 115°C and polyether polyol HF505 (molecular weight 11400) 15.92 parts by mass and 800 (molecular weight 280) 5.31 parts by mass kept at 25-65°C for use. 800 and The stoichiometric ratio of the sum of the OH groups of HF505 to the NCO groups of the isocyanate-terminated prepolymer is 100%.

[0153] 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 sheets with thicknesses of 80 mil, 50 mil, and 120 mil.

[0154] Step 4: Select a thin sheet with a thickness of 80 mils. The groove shape uses concentric grooves with a blank (ungrooved) area in the center. The groove parameters are: groove depth 30 mils, groove width 20 mils, groove spacing 120 mils, and the diameter of the center blank area is 5 inches. After grooving, it becomes a polishing layer.

[0155] 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 PD1, wherein the buffer layer uses polyurethane impregnated non-woven fabric material Z70 (purchased from Dinglong Co., Ltd.).

[0156] Comparative Example 2

[0157] This comparative example provides a polishing pad, and the preparation method is as follows:

[0158] Step 1: Take 100 parts by mass LF667 isocyanate-terminated prepolymer was heated to 25-65°C, degassed under vacuum (-0.095 MPa) for 2 hours, and then 1.40 parts by mass of hollow microsphere polymer 920DE 40d30 was added, and the hollow microsphere polymer was uniformly dispersed in the prepolymer under stirring, and degassed again under vacuum (-0.095 MPa) for 2 hours for standby use. The unreacted NCO in the isocyanate-terminated prepolymer was 6.7%.

[0159] Step 2: Curing agent composition: polyether polyol HF505 (molecular weight 11400) 55.93 parts by mass and 800 (molecular weight 280) 9.11 parts by mass kept at 25-65°C for use. 800 and The stoichiometric ratio of the sum of the OH groups of HF505 to the NCO groups of the isocyanate-terminated prepolymer is 100%.

[0160] 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 sheets with thicknesses of 80 mil, 50 mil, and 120 mil.

[0161] Step 4: Select a thin sheet with a thickness of 80 mils. The groove shape uses concentric grooves with a blank (ungrooved) area in the center. The groove parameters are: groove depth 30 mils, groove width 20 mils, groove spacing 120 mils, and the diameter of the center blank area is 5 inches. After grooving, it becomes a polishing layer.

[0162] 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 PD2, wherein the buffer layer uses polyurethane impregnated non-woven fabric material Z70 (purchased from Dinglong Co., Ltd.).

[0163] Shore hardness of polishing layer

[0164] 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%.

[0165] Density of polishing layer

[0166] 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.

[0167] Polishing layer loss height h2

[0168] Use as Figure 3The device shown includes a transparent tube with an inner diameter of 35 mm, a steel ball with a diameter of 16 mm and a mass of 16.8 ± 1.5 g, and a falling height h of 500 mm. The steel ball cannot touch the transparent tube during the falling process. The steel ball is released by a magnet or other device, and the height h1 is recorded when it rebounds to a linear velocity of 0 after contacting the measured object, where h2 of the polishing layer = hL-h1. The measured object is a polishing layer sample of 100 mm*100 mm, which may or may not contain grooves.

[0169] Polishing pad rebound performance test

[0170] Use as Figure 3 The device shown includes a transparent tube with an inner diameter of 35 mm, a steel ball with a diameter of 16 mm and a mass of 16.8 ± 1.5 g, and a falling height h of 500 mm. The steel ball cannot touch the transparent tube during the falling process. The steel ball is released by a magnet or other device, and the height h1 is recorded when it rebounds to the moment when the linear velocity is 0 after contacting the measured object. The rebound energy = h1 / h*100%. The polishing pad sample with a measured object of 100 mm*100 mm may or may not contain grooves. The test results are shown in Table 1.

[0171] Table 1

[0172] serial number <![CDATA[Density (g / cm 3 )]]> Hardness (D) H(mm) L(mm) Thickness(mil) <![CDATA[h2(80mil)]]> Thickness(mil) <![CDATA[h2(50mil)]]> Thickness(mil) <![CDATA[h2(120mil)]]> Example 1 0.80 61.0 500 16 80.0 365.8 50.0 409.1 120.0 326.7 Example 2 0.71 59.6 500 16 80.0 376.2 50.0 415.7 120.1 340.4 Example 3 0.50 46.1 500 16 80.0 406.5 50.0 439.8 120.0 380.8 Example 4 0.81 62.2 500 16 80.0 364.8 50.0 408.4 120.0 325.2 Example 5 0.82 66.3 500 16 80.0 363.7 50.0 407.8 120.2 323.8 Example 6 1.01 72.4 500 16 80.0 345.7 50.0 396.3 120.0 280.4 Example 7 0.89 58.3 500 16 80.0 356.6 50.0 403.3 120.0 314.4 Example 8 0.95 64.2 500 16 80.0 351.0 50.0 399.7 120.1 306.9 Comparative Example 1 0.78 19.2 500 16 80.0 447.8 50.0 461.1 120.0 442.2 Comparative Example 2 0.81 7.1 500 16 80.0 454.7 50.0 465.4 120.0 445.0

[0173] Polishing performance evaluation of polishing pads

[0174] 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:

[0175] The test machine is AMAT Refelxion (Modify 5Zone);

[0176] The polishing wafer was a 300 mm 3S20KTENTEOS (oxide) blanket wafer purchased from Novellus Systems, Inc.; the slurry used for polishing was CES333F slurry (purchased from Asahi Glass Company), the polishing conditions used included a platen speed of 92 rpm, a carrier speed of 93 rpm, a slurry flow rate of 250 ml / min, and a downforce of 20.7 kPa, an I-PDA31G-3N diamond conditioning disc (purchased from Kinik Company) was used to condition the chemical mechanical polishing pad, and the chemical mechanical polishing pad was interrupted ex situ with a conditioner using a downforce of 7.5 lbs (3.40 kg) for 40 min each, the polishing pad was further conditioned ex situ, and then polished for 18 seconds using a downforce of 7.5 lbs (3.40 kg), and the removal rate was measured by KLA-Tencor, and the removal rate (TEOS RR) is shown in the following table:

[0177] Defect evaluation

[0178] The defects on the polished substrate after polishing are obtained using KLA-Tencor The SP2 defect inspection system was used to inspect the defect size: 0.16 μm, and the 10th wafer was measured. The evaluation results are shown in Table 2.

[0179] Table 2

[0180]

[0181] 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 layer, comprising a closed-cell elastomer formed by a continuous polyurethane substrate separated by pores of 5 to 100 μm, wherein the polyurethane substrate comprises a reaction product of a prepolymer terminated by isocyanate and a curing agent; the polishing layer comprises a polishing surface, a sphere with a mass of m and a diameter of L is freely released at a distance h above the polishing surface, and the height from the bottom of the metal ball to the polishing surface when the sphere contacts the polishing surface to the moment when the metal ball rebounds upward to a linear velocity equal to 0 is h1, when h is between 490 mm and 520 mm, the mass m of the sphere is between 15 g and 19 g, and the diameter L of the sphere is between 15 mm and 17 mm, wherein, The loss height h2=h-h1-L, and the loss height h2 is between 280 mm and 440 mm.

2. The polishing layer according to claim 1, characterized in that The thickness of the polishing layer is between 50 mil and 120 mil.

3. The polishing layer according to claim 1, characterized in that The density of the polishing layer is between 0.4 g / cm 3 ~1.1g / cm 3 Preferably, the density of the polishing layer is between 0.5 g / cm 3 ~1.05g / cm 3 , particularly preferably, the density of the polishing layer is between 0.6 g / cm 3 ~1.0g / cm 3 .

4. The polishing layer according to claim 1, characterized in that The isocyanate-terminated prepolymer comprises a reaction product of a polyfunctional isocyanate and a polyol.

5. The polishing layer according to claim 4, characterized in that The polyfunctional isocyanate includes 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, m-xylylene diisocyanate, ethylene diisocyanate, 2,2,4-triisocyanate, One or more combinations of methyl hexamethylene diisocyanate, 1,6-hexamethylene diisocyanate, 1,4-cyclohexane diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, isophorone diisocyanate, and norbornane diisocyanate; preferably, the multifunctional isocyanate comprises one or more combinations of 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, and 4,4'-dicyclohexylmethane diisocyanate.

6. The polishing layer according to claim 4, characterized in that The polyol comprises one or more combinations of polytetramethylene ether glycol, polyethylene glycol, polypropylene glycol, ethylene glycol, butanediol, diethylene glycol, neopentyl glycol, 2-methyl-1,3-propanediol, hexanediol, 3-methyl-1,5-pentanediol, 1,4-cyclohexanedimethanol, homopolymers and / or copolymers of ethylene oxide and propylene oxide; preferably, the polyol comprises one or more combinations of polytetramethylene ether glycol, polypropylene glycol, diethylene glycol, homopolymers and / or copolymers of ethylene oxide and propylene oxide.

7. The polishing layer according to claim 1, characterized in that The curing agent comprises a polyamine curing agent or a polyol curing agent.

8. The polishing layer according to claim 7, characterized in that The polyamine curing agent includes 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) (MCDE A), polyoxytetramethylene-di-p-aminobenzoate; p,p'-methylenedianiline (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; preferably, the polyamine curing agent is 4,4'-methylene-bis-(2-chloroaniline) (MOCA).

9. The polishing layer according to claim 7, characterized in that The polyol curing agent has a number average molecular weight of 2,000 to 100,000, and the polyol curing agent has an average of 3 to 30 hydroxyl groups. Preferably, the polyol curing agent contains 4 to 8 hydroxyl groups.

10. The polishing layer according to claim 1, characterized in that The unreacted NCO of the isocyanate-terminated prepolymer is between 8.0% and 9.5%, and the stoichiometric ratio of the NH2 and / or OH from the curing agent to the NCO of the isocyanate-terminated prepolymer is between 80% and 105%.

11. A polishing pad for chemical mechanical polishing of at least one substrate selected from a magnetic substrate, an optical substrate and a semiconductor substrate, characterized in that: The polishing pad comprises the polishing layer according to any one of claims 1 to 10.

12. A polishing pad for chemical mechanical polishing of at least one substrate selected from the group consisting of a magnetic substrate, an optical substrate and a semiconductor substrate, characterized in that: The resilience of the polishing pad is between 5% and 40%.

13. The polishing pad according to claim 12, characterized in that The polishing pad comprises a polishing layer, an intermediate adhesive layer, a buffer layer and a release film layer.

14. A method for manufacturing a semiconductor device, characterized in that: A semiconductor device is provided, comprising a substrate selected from at least one of a magnetic substrate, an optical substrate or a semiconductor substrate, a polishing pad as described in claim 11 or 12, dynamic contact is formed between the polishing surface of the polishing layer and the substrate to polish the surface of the substrate, and the polishing surface is dressed using an abrasive dresser.

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