A polyurethane composition and a chemical mechanical polishing pad window made therefrom

Abstract

The present application relates to a kind of polyurethane compositions, at least comprising 14.0-20.0wt% of toluene diisocyanate, 20.0-38.0wt% of dicyclohexylmethane diisocyanate, 39.0-57.0wt% of polytetramethylene ether glycol and 3.0-9.0wt% of small molecule dihydric alcohol polyurethane prepolymer component A;And the solidification agent component B formed by aromatic diamine and polyethylene oxide dihydric alcohol;And polysiloxane microsphere component C.The polyurethane composition of the present application obtains window material through curing process, further manufacture forms polished layer with integral window.The window of chemical mechanical polishing pad made by the present application still has higher light transmittance under the condition that surface presents certain roughness (Ra≤10 μm);And its hardness and dynamic mechanical properties can be easily adjusted, provide higher matching with polishing pad.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of chemical mechanical polishing, in particular to a polyurethane composition for manufacturing a chemical mechanical polishing pad window material and a chemical mechanical polishing pad window manufactured therefrom. BACKGROUND

[0002] Chemical mechanical polishing (CMP) is a process technology for manufacturing semiconductor devices, mainly used for global planarization of silicon wafers or other substrate materials. The CMP process is a combination of chemical action and mechanical grinding to remove micron / nanometer level materials on the surface of wafers or other substrates. The main consumables involved include polishing liquid and polishing pad.

[0003] Chemical mechanical polishing pads (CMP pads) are classified into various specifications according to different process procedures and polishing objects. Different specifications are mainly based on the physical properties and internal porosity of polishing pad materials. Hardness is an important physical property of polishing pads. Depending on different applications, various hardness specifications in the range of 45-70D have appeared.

[0004] A key technology for controlling the CMP process is how to determine the polishing endpoint. Various endpoint monitoring methods based on mechanics, optics and electromagnetics have been developed. Among them, the implementation of the optical endpoint monitoring method requires a relatively transparent area to be set at a specific position of the polishing pad for transmission of optical signals. This area is commonly referred to as a polishing pad window. As part of the polishing pad, the window not only needs to play the role of optical signal transmission, but also needs to undergo mechanical grinding during polishing together with the polishing pad. Therefore, the selection of the window material not only needs to consider the sustained stability of the light transmission performance during the entire polishing life, but also needs to consider the matching of the window with the mechanical properties of different polishing pads.

[0005] The prior art manufactured polishing pad window, such as the window material disclosed in CN102310366 B, is a reaction product of an isocyanate-terminated prepolymer and an amine curing agent (such as 3,3'-dichloro-4,4'-diphenylmethane diamine, MOCA). Specifically, the prepolymer is formed by reacting an aromatic isocyanate (containing most preferably less than 12 wt% of aliphatic isocyanate) with polytetramethylene glycol (PTMEG) to form a prepolymer having an NCO content of 8.75-9.40 wt%. The window material is manufactured based on a stoichiometric ratio of amine moieties to unreacted NCO moieties of 1:1 to 1:1.25, and the window material obtained therefrom has a light transmittance at 670 nm of 20-50% (at a thickness of about 1.27 mm), which not only lacks the light transmittance required for high-demand polishing applications, but also is not suitable for polishing pads of all hardness specifications because the hardness of the window material is limited to a narrow range (64-70D).

[0006] Reported invention cases, such as CN100347826 C and CN102161182 B, mainly use aliphatic isocyanate as a basic component to form an aliphatic polyurethane window material to achieve the purpose of improving the light transmittance of the window.

[0007] J. V. H. Roberts discloses in CN100347826 C that the window material is formed by reacting a prepolymer of an aliphatic polyisocyanate and a hydroxyl-containing material with a curing agent. In one embodiment, the prepolymer is formed by mixing LW520 (a commercially available prepolymer containing aliphatic isocyanate) and a curing agent at room temperature and degassing to form a prepolymer. The prepolymer is then heated to 65.6°C and maintained at this temperature for 1 hour. The prepolymer is then cooled to room temperature and mixed with a curing agent to form the window material. LW520 or LW570 (a commercially available prepolymer containing aliphatic isocyanate) and a curing agent at room temperature are mixed and degassed to form the window material. The polishing pad window comprising the window material has improved laser signal transmission, providing greater light signal intensity (e.g., relative intensity when a light beam exits / enters the window).

[0008] In CN102161182 B, A. Lojac et al. disclose that the window material is formed by reacting a prepolymer of an aliphatic or alicyclic isocyanate and a polyol with an amine chain extender. The polishing pad window processed therefrom has high light transmittance and durability required for polishing applications, and does not have a convex window.

[0009] According to the above-mentioned reports of the prior art, the inventors of the present application have also conducted corresponding verification. Although the aliphatic polyurethane window material has the advantage of high light transmittance, it also has many disadvantages, mainly being slow in curing and forming, having a narrow range of hardness adjustment, and having dynamic mechanical properties and grinding characteristics that are quite different from those of the aromatic polyurethane material forming the polishing layer.

[0010] At present, with the increasing application requirements of CMP process, the characteristics of polishing pad window are required to be more differentiated and refined, which is specifically shown as follows: 1) based on the IC 1000 standardized product (about 60D), polishing pads with various hardness specifications in the range of 45-70D appear, and the hardness and dynamic mechanical properties of the corresponding window should also be differentiated to a certain extent; 2) higher light transmittance, especially in the application condition that the window presents a certain roughness (Ra≤10μm) on the upper and lower surfaces. SUMMARY

[0011] It has been found that a cast polyurethane elastomer manufactured from a composition comprising a polyurethane prepolymer component A, a curing agent component B and a polysiloxane microsphere component C has high light transmittance, and its hardness and dynamic mechanical properties and other properties can be easily adjusted, and is suitable for use as a chemical mechanical polishing pad window material, thereby completing the present application.

[0012] The object of the present application is to provide a polyurethane composition and a performance improved chemical mechanical polishing pad window manufactured therefrom, and the polishing pad window formed therefrom still has high light transmittance in the case that the surface presents a certain roughness (Ra≤10μm), and its hardness and dynamic mechanical properties and other properties can be easily adjusted to have higher matching with polishing pads with different property specifications.

[0013] To achieve the above-mentioned object of the application, the technical scheme adopted by the present application is as follows:

[0014] A polyurethane composition, the composition at least comprising: a polyurethane prepolymer component A, a curing agent component B, and a polysiloxane microsphere component C;

[0015] The polyurethane prepolymer component A is a reaction product comprising the following components:

[0016] (A1) 14.0-20.0 wt% of toluene diisocyanate (TDI) and 20.0-38.0 wt% of cyclohexylmethane diisocyanate (HMDI);

[0017] (A2) 39.0-57.0 wt% of polytetramethylene ether glycol;

[0018] (A3) 3.0-9.0 wt% of a small molecule diol;

[0019] The curing agent component B is a mixture at least comprising the following components,

[0020] (B1) 40-70 wt% of an aromatic diamine chain extender;

[0021] (B2) 30-60 wt% of a polyethylene oxide diol;

[0022] wherein the polysiloxane microsphere component C has a particle size of 0.2-8.0 microns and a refractive index of 1.40-1.46; preferably, the polysiloxane microsphere component C is added to the polyurethane prepolymer component A in an amount of 0.01-0.1 wt%.

[0023] In a specific embodiment, the polyurethane prepolymer component A is a reaction product of the following components:

[0024] (A1) 15.5-18.5 wt% of toluene diisocyanate (TDI) and 22.0-35.5 wt% of dicyclohexylmethane diisocyanate (HMDI); the toluene diisocyanate is a mixture of 2,4-TDI and 2,6-TDI, wherein the content of 2,4-TDI is 80-100%; the content of 2,4-HMDI in the cyclohexylmethane diisocyanate is 6-10%;

[0025] (A2) 42.0-55.0 wt% of polytetramethylene ether glycol; preferably, the polytetramethylene ether glycol has a molecular weight of 650-1500, preferably a molecular weight of 1000;

[0026] (A3) 4.0-7.5 wt% of a small molecule diol; preferably, the small molecule diol has a molecular weight of less than 200, preferably selected from one or more of ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propanediol, 1,3-propanediol, dipropylene glycol, tripropylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, or 1,6-hexanediol, more preferably diethylene glycol, 1,3-butanediol, or a mixture thereof.

[0027] In a specific embodiment, the polyurethane prepolymer component A is a reaction product of the reaction components under continuous stirring, at a reaction temperature of 40-100°C for a reaction time of 4-12 h; the polyurethane prepolymer component A has an isocyanate group (NCO) content of 7.0-10.0 wt%, preferably 7.5-9.5 wt%.

[0028] In a specific embodiment, the polyurethane prepolymer component A contains at least one liquid polybutadiene component in an amount of 0.1-0.6 wt%, preferably 0.2-0.4 wt%.

[0029] In a specific embodiment, the curing agent component B is a mixture containing at least the following components:

[0030] (B1) 55-65 wt% of an aromatic diamine chain extender, preferably the aromatic diamine chain extender comprises at least one or more of 3,3'-dichloro-4,4'-diphenylmethane diamine (MOCA), 3,5-dimethylthio-toluene diamine (DMTDA), 3,5-diethyl-toluene diamine (DETDA), 4,4'-methylenebis(3-chloro-2,6-diethyl aniline) (M-CDEA), 4,4'-methylenebis(2,6-diethyl aniline) (M-DEA), and 1,3-propanediol bis(4-aminobenzoate) (740M), preferably MOCA or a mixture of MOCA and M-CDEA;

[0031] (B2) 35-45 wt% of a polyethylene oxide glycol; preferably the polyethylene oxide glycol (B2) has a relative molecular mass of 600-1500, preferably a relative molecular mass of 1000.

[0032] In one specific embodiment, the curing agent component B is a homogeneous, stable mixture formed by the aromatic diamine chain extender and the polyethylene oxide glycol component at a material temperature of 60-110 °C under continuous stirring.

[0033] In one specific embodiment, the polysiloxane microsphere component C has a particle size of 1.0-6.0 microns; a refractive index of 1.42-1.45; preferably the polysiloxane microsphere component C is added to the polyurethane prepolymer component A in an amount of 0.03-0.06 wt%.

[0034] In another aspect, a chemical mechanical polishing pad window, the window material having a hardness of 45-75D, the window material being prepared by the steps comprising:

[0035] Step 1, providing the polyurethane composition of any one of claims 1-7, the polyurethane composition comprising at least: a polyurethane prepolymer component A, a curing agent component B, and a polysiloxane microsphere component C;

[0036] Step 2, forming a reactive mixture of the polyurethane prepolymer component A, the curing agent component B, and the polysiloxane microsphere component C;

[0037] Step 3, subjecting the reactive mixture to a vacuum degassing process;

[0038] Step 4, subjecting the reactive mixture to a curing process.

[0039] In one specific embodiment, the stoichiometric ratio of the reactive groups of the curing agent component B and the polyurethane prepolymer component A (i.e. ([OH] + [NH2]) / [NCO]) is 0.8-1.0.

[0040] In one specific embodiment, the vacuum degassing process is injecting the reactive mixture into a mold, and staying for 6-20 min under a relative vacuum degree of no more than -99 KPa; preferably, the curing process is staying for 12-48 h at a temperature atmosphere of 80-120℃, preferably 16-24 h at a temperature atmosphere of 95-115℃.

[0041] Compared with the prior art, the present application has the following beneficial effects:

[0042] The polyurethane composition of the present application comprises a polyurethane prepolymer component A, a curing agent component B, and a polysiloxane microsphere component C, and the cast polyurethane elastomer manufactured therefrom has high light transmittance, and its hardness and dynamic mechanical properties can be easily adjusted, and is suitable for use as a chemical mechanical polishing pad window material.

[0043] The polishing pad window material manufactured by using the polyurethane composition of the present application has a hardness in the range of 45-75D, which can be adjusted to adapt to polishing pads of different hardness specifications; and the window surface has a certain roughness (Ra≤10 microns), and has high single transmittance and double transmittance of light at a wavelength of about 630 nm. DETAILED DESCRIPTION

[0044] The technical solutions of the present application will be further described below by means of specific embodiments. Those skilled in the art should understand that the embodiments are only used to help understand the present application, and should not be regarded as specific limitations on the present application.

[0045] The polyurethane composition of the present application at least comprises a polyurethane prepolymer component A, a curing agent component B, and a polysiloxane microsphere component C.

[0046] The polyurethane prepolymer component A is a reaction product of a mixture of a certain amount of toluene diisocyanate (TDI) and dicyclohexyl methane diisocyanate (HMDI) with a certain amount of polytetramethylene ether glycol (PTMEG) and a certain amount of a small molecule diol.

[0047] Specifically, the polyurethane prepolymer component A is a reaction product comprising the following components:

[0048] (A1) 14.0-20.0 wt% of toluene diisocyanate (TDI) and 20.0-38.0 wt% of dicyclohexyl methane diisocyanate (HMDI);

[0049] (A2) 39.0-57.0 wt% of polytetramethylene ether glycol;

[0050] (A3) 3.0-9.0 wt% of a small molecule diol.

[0051] In one preferred embodiment, the polyurethane prepolymer component A is the reaction product of the following components:

[0052] (A1) 15.5-18.5 wt% of toluene diisocyanate (TDI) and 22.0-35.5 wt% of dicyclohexylmethane diisocyanate (HMDI);

[0053] (A2) 42.0-55.0 wt% of polytetramethylene ether glycol; preferably, the polytetramethylene ether glycol has a molecular weight of 650-1500, preferably 1000;

[0054] (A3) 4.0-7.5 wt% of a small molecule diol; preferably, the small molecule diol has a molecular weight of less than 200, preferably one or more selected from the group consisting of ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propanediol, 1,3-propanediol, dipropylene glycol, tripropylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, or 1,6-hexanediol, more preferably diethylene glycol, 1,3-butanediol, or a mixture thereof.

[0055] The toluene diisocyanate (TDI) referred to in the present application is a common industrial chemical, and products are commercially available from Wanhua Chemical, BASF, and Covestro, etc. The TDI industrial product is mainly a mixture of 2,4-TDI and 2,6-TDI in a mass ratio of 80:20 (referred to as TDI-80), in addition to TDI-100 (pure 2,4-TDI).

[0056] The toluene diisocyanate referred to in the present application has a 2,4-TDI content of 80-100%. In the present application, TDI-100 and TDI-80 industrial products are mixed in a certain mass ratio to obtain TDI with a 2,4-TDI mass fraction of 80-100%.

[0057] In the present application, the amount of toluene diisocyanate (TDI) in the reactants is 14.0-20.0 wt%, based on the total amount of the polyurethane prepolymer reactants, for example including but not limited to 14 wt%, 15 wt%, 16 wt%, 17 wt%, 18 wt%, 19 wt%, 20 wt%, preferably 15.5-18.5 wt%.

[0058] The dicyclohexylmethane diisocyanate involved in the present application is a kind of alicyclic diisocyanate, which is abbreviated as HMDI. HMDI has two symmetrical cyclohexyl groups in the molecule, and has low reactivity compared with toluene diisocyanate, and is suitable for manufacturing transparent polyurethane materials with excellent light stability. HMDI includes two isomers of 2,4-HMDI and 4,4-HMDI, and the common HMDI industrial product is mainly composed of 4,4-HMDI isomer. The HMDI involved in the present application contains 6-10% of 2,4-HMDI, and the commercially available products such as Covestro Desmodur W and Wannate H1210 of Wanhua Chemical.

[0059] In the present application, the amount of dicyclohexylmethane diisocyanate (HMDI) in the reactants is 20.0-38.0wt%, for example, including but not limited to 20wt%, 22wt%, 24wt%, 26wt%, 28wt%, 30wt%, 32wt%, 34wt%, 36wt%, 38wt%, preferably 22.0-35.5wt%.

[0060] In the present application, the amount of polytetramethylene ether glycol (PTMEG) in the reactants is 39.0-57.0wt%, for example, including but not limited to 39wt%, 40wt%, 41wt%, 42wt%, 43wt%, 44wt%, 45wt%, 46wt%, 47wt%, 48wt%, 49wt%, 50wt%, 51wt%, 52wt%, 53wt%, 54wt%, 55wt%, 56wt%, 57wt%, preferably 42.0-55.0wt%; the molecular weight of polytetramethylene ether glycol (PTMEG) is preferably 650-1500, for example, 650, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, etc., more preferably the molecular weight is 1000, for example, there are corresponding commercially available products from INVISTA Corporation of the United States, Mitsubishi Chemical of Japan, BASF of Germany, etc.

[0061] In the present application, the amount of small molecule diol in the reactants is 3.0-9.0wt%, for example, including but not limited to 3wt%, 4wt%, 5wt%, 6wt%, 7wt%, 8wt%, 9wt%, preferably 4.0-7.5wt%; the molecular weight of the small molecule diol is less than 200, for example, a mixture of one or more selected from ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propanediol, 1,3-propanediol, dipropylene glycol, tripropylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol and 1,6-hexanediol, preferably diethylene glycol (abbreviated as DEG), 1,3-butanediol (abbreviated as 1,3-BG) or a mixture thereof.

[0062] The polyurethane prepolymer of the present application can be prepared by a conventional method in the art. For example, it is completed by the raw material components including isocyanate component, polytetramethylene ether glycol, and small molecule diol, etc. under continuous stirring. The reaction temperature is generally 40-100°C, for example, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, preferably 60-80°C, and the reaction time is 4-12h, for example, 4h, 5h, 6h, 7h, 8h, 9h, 10h, 11h, 12h, preferably 6-10h.

[0063] The isocyanate group (NCO) content of the polyurethane prepolymer component A is 7.0-10.0wt%, for example, 7wt%, 7.5wt%, 8wt%, 8.5wt%, 9wt%, 9.5wt%, 10wt%, preferably 7.5-9.5wt%.

[0064] The polyurethane prepolymer of the present application preferably further contains at least one liquid polybutadiene component, and the polybutadiene is non-functionalized liquid polybutadiene and / or maleic anhydride grafted liquid polybutadiene, and the average molecular weight is 2000-6000g / mol. The non-functionalized liquid polybutadiene and the maleic anhydride grafted liquid polybutadiene involved in the present application are not particularly limited, but for example, non-functionalized liquid polybutadiene such as POLYVEST 110 (EVONIK), POLYWEST 130 (EVONIK), etc. can be mentioned; maleic anhydride grafted liquid polybutadiene such as POLYVEST EP MA120 (EVONIK), OLYVEST MA75 (EVONIK), etc. can be mentioned.

[0065] In the present application, in order to facilitate the addition of the polybutadiene to the polyurethane prepolymer, the polybutadiene is generally dissolved in an aliphatic diester compound to form a low-viscosity polybutadiene solution. Generally, the mass ratio of the polybutadiene compound to the aliphatic diester compound is 1:0.5-1:5, for example, 1:0.5, 1:1, 1:1.5, 1:2, 1:2.5, 1:3, 1:3.5, 1:4, 1:4.5, 1:5, etc., preferably 1:1-1:3.

[0066] The aliphatic diester compound is selected from one or two or more of dimethyl adipate, dibutyl adipate, di-n-hexyl adipate, dioctyl adipate, diethyl sebacate, dibutyl sebacate, dioctyl sebacate, dioctyl azelate.

[0067] In the polyurethane prepolymer component A of the present application, the content of the liquid polybutadiene component is 0.1-0.6wt%, for example, 0.1wt%, 0.2wt%, 0.3wt%, 0.4wt%, 0.5wt%, 0.6wt%, etc., preferably 0.2-0.4wt%.

[0068] Optionally, an amount of acidic substance can be added during the preparation of the polyurethane prepolymer component A, including: acyl chlorides such as one or more of adipoyl chloride, benzoyl chloride, and benzenesulfonyl chloride; phosphates such as one or more of di-n-butyl phosphate, di-iso-octyl phosphate. The amount added is typically 10 to 200 ppm, based on the total amount of the polyurethane prepolymer.

[0069] The polyurethane composition described herein comprises a curing agent component B which is a mixture of an aromatic diamine-based chain extender and a polyoxyethylene glycol. Specifically, the curing agent component B is a mixture comprising at least,

[0070] (B1) 40 to 70 wt% of the aromatic diamine-based chain extender;

[0071] (B2) 30 to 60 wt% of the polyoxyethylene glycol.

[0072] In one preferred aspect, the curing agent component B is a mixture comprising at least,

[0073] (B1) 55 to 65 wt% of the aromatic diamine-based chain extender;

[0074] (B2) 35 to 45 wt% of the polyoxyethylene glycol.

[0075] The aromatic diamine-based chain extender comprises at least 3,3'- dichloro-4,4'-diphenylmethane diamine (MOCA), and can further comprise one or more of 3,5- dimethylthio-toluene diamine (DMTDA), 3,5-diethyl-toluene diamine (DETDA), 4,4'-methylenebis(3- chloro-2,6-diethylbenzenamine) (M-CDEA), 4,4'-methylenebis(2,6-diethylbenzenamine) (M-DEA), and 1,3-propanediol bis(4-aminobenzoate) (740M), preferably MOCA or a mixture of MOCA and M-CDEA; the amount of the aromatic diamine-based chain extender is 40 to 70 wt%, based on 100 parts by mass of the curing agent component, for example including but not limited to 40 wt%, 45 wt%, 50 wt%, 55 wt%, 60 wt%, 65 wt%, 70 wt%, preferably 55 to 65 wt%;

[0076] The polyoxyethylene glycol has a relative molecular mass of 600-1500, such as 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, etc., and preferably has a relative molecular mass of 1000; the curing agent component contains 30-60 wt% of the polyoxyethylene glycol, such as 30 wt%, 35 wt%, 40 wt%, 45 wt%, 50 wt%, 55 wt%, 60 wt%, preferably 35-45 wt%, based on 100 parts by mass.

[0077] The polyoxyethylene glycol has a metal ion (iron, sodium, potassium) content of less than 5 ppm, and in particular, the potassium ion content is controlled to a maximum of 3 ppm, and preferably a maximum of 2 ppm. The determination method of the metal ion is described in GB / T 12008.4-2009 Plastics - Polyether polyols - Part 4: Determination of sodium and potassium. Corresponding commercially available products, such as the products of Dow Chemical with the trade name CARBOWAX SENTRY PEG600, PEG1000 and PEG1500, and the products of Hanhao Chemical with the trade name KOREMUL PEG600A, PEG1000A and PEG1500A.

[0078] The forming method of the curing agent component B comprises the following steps: firstly, heating and melting the flaky solid MOCA at 110-120°C to form a liquid compound; secondly, maintaining the polyoxyethylene glycol at a material temperature of 60-110°C; and finally, continuously stirring a mixture of the liquid MOCA and the polyoxyethylene glycol to form a uniform and stable mixture. In the forming process of the curing agent component B, in addition to MOCA, other aromatic diamine chain extenders are also included, and preferably the mixture of MOCA and M-CDEA, and the content of M-CDEA in the curing agent component B is ≤3%, and preferably ≤2%.

[0079] In the present application, the polysiloxane microsphere component C has a diameter distribution of 0.2-8.0 microns, and preferably has a diameter distribution of 1.0-6.0 microns; and the refractive index of the polysiloxane microsphere component C is 1.40-1.46, and preferably is 1.42-1.45.

[0080] In the present application, the polysiloxane microsphere component C is added to the polyurethane prepolymer, and continuously stirred to form a uniform mixture, and the addition amount of the polysiloxane microsphere component C in the polyurethane prepolymer is 0.01-0.1 wt%, and preferably is 0.03-0.06 wt%.

[0081] In this invention, the polysiloxane microsphere component C can be one or more of the following brands: KMP-590, KMP-702, KMP-701, X-52-854, and X-52-1621 from Shin-Etsu Chemical: KMP-590, KMP-702, KMP-701, X-52-854, and X-52-1621.

[0082] The chemical mechanical polishing pad window material of the present invention is obtained by forming a reactive mixture of polyurethane prepolymer component A, curing agent component B, and polysiloxane microsphere component C in a certain proportion. The stoichiometric ratio of the reactive groups of curing agent component B and polyurethane prepolymer component A (i.e., ([OH]+[NH2]) / [NCO]) is 0.8-1.0, preferably 0.84-0.92; the reactive mixture is obtained by continuous stirring at a certain material temperature for a certain period of time.

[0083] Typically, the temperature of polyurethane prepolymer component A is 50-60℃, and the temperature of curing agent component B is 60-110℃; suitable impeller types include disc impellers, "I" shaped impellers, and "W" shaped impellers. In one embodiment of the present invention, the mass of the reactive mixture is 600 grams, the suitable rotation speed is 600 rpm, and the suitable stirring time is 2 minutes.

[0084] In this invention, the manufacturing of the chemical mechanical polishing pad window material includes subjecting the reactive mixture to a vacuum degassing process. Specifically, the reactive mixture formed by stirring is rapidly injected into a mold and held at a relative vacuum of no more than -99 kPa for 6-20 minutes. In an embodiment of this invention, the reactive mixture formed by stirring is rapidly injected into a rectangular aluminum mold (the inner wall of the mold cavity is coated with a Teflon liner), and the mold is placed in a vacuum oven at 80°C and held at a relative vacuum of -100 kPa for 10 minutes.

[0085] In this invention, the manufacturing of the chemical mechanical polishing pad window material includes subjecting the vacuum-degassed molded article to a curing process, wherein the curing process involves holding the vacuum-degassed molded article in a temperature atmosphere of 80-120°C for 12-48 hours, preferably in a temperature atmosphere of 95-115°C for 16-24 hours.

[0086] In this invention, the hardness of the window material after the curing process is 45-75D at 24-26℃.

[0087] The manufacture of the chemical mechanical polishing pad with an integral window according to the present invention includes:

[0088] Window blocks of a specific shape are processed by cutting, milling, and grinding. They are usually cuboids with a length of about 57 mm, a width of about 19 mm, and a height of 30-60 mm.

[0089] The window block is fixed to a specific position of the circular mold base, and the position change is mainly based on the different diameters of the circular mold (mainly including 660 mm and 906 mm);

[0090] The reactive polyurethane mixture for forming the polishing pad is poured at the center of the mold, and the mixture is allowed to flow naturally in the mold to form a product similar to a cake, and the height of the cake is generally 30-60 mm;

[0091] The cake containing the integral window is allowed to react under certain conditions, and the reactive active groups are allowed to fully react, generally at 105°C for 16H; the cake is maintained at a certain temperature, generally 50-100°C, preferably 65-85°C, and the cake is cut into a sheet, or the surface thereof is sanded as needed.

[0092] In the present application, the surface roughness (Ra) of the integral window of the chemical mechanical polishing pad obtained according to the above manufacturing process is ≤10 microns, and the light transmittance at a wavelength of 630 nm is high.

[0093] The present application will be further explained and described below by more specific examples, but without any limitation.

[0094] The main raw materials involved in the following examples and comparative examples are as follows:

[0095] TDI-80: toluene diisocyanate, the mass fraction of 2,4-TDI is about 80%, and the product brand of Wanhua Chemical is Wannate TDI-80.

[0096] TDI-100: toluene diisocyanate, the mass fraction of 2,4-TDI is about 99.9%, and the product brand of Wanhua Chemical is Wannate TDI-100.

[0097] TDI-90: toluene diisocyanate, the mass fraction of 2,4-TDI is about 90%, and it is prepared by mixing Wannate TDI-80 and Wannate TDI-100 according to a mass ratio of 1:1.

[0098] HMDI: dicyclohexylmethane diisocyanate, the content of 2,4-HMDI is about 9.5wt%, and the product brand of Wanhua Chemical is Wannate H1210.

[0099] P-1000: molecular weight is 1000, and the product of Mitsubishi Chemical of Japan is PTMEG-1000.

[0100] DEG: diethylene glycol, purity >99.9wt%, and Comie.

[0101] 1,3-BG: 1,3-butanediol, purity >99.9wt%, Aldrich.

[0102] Polyvest 130, average molecular weight about 1300 g / mol, Evonik product. Dioctyl adipate, dioctyl sebacate and Polyvest 130 were weighed according to mass ratio 5:1:4, respectively, mixed uniformly to form Polyvest 130 mixture, noted as 5132.

[0103] Phosphoric acid diisooctyl ester (IOAP): purity >99.4wt%, Aldrich.

[0104] MOCA: 3,3’ dichloro-4,4’-diphenylmethane diamine, Double Bond, Taiwan, China.

[0105] M-CDEA: 4,4’ methylene bis(3-chloro-2,6-diethylaniline), Suzhou Xiangyuan.

[0106] PEG-1000A: polyoxyethylene glycol, Mn about 1000, Fe: 1.8ppm, Na: 1.2ppm, K: 1.5ppm, Hanhao Chemical.

[0107] KMP-702: Shin-Etsu Chemical, refractive index 1.43, average diameter 2 microns.

[0108] KMP-701: Shin-Etsu Chemical, refractive index 1.43, average diameter 3.5 microns.

[0109] Preparation of polyurethane prepolymer component A

[0110] Preparation of prepolymer A-1:

[0111] First, according to the prepolymer A-1 formula TDI-80: HMDI: PTMEG-1000: DEG: 1,3-BG = 16.5: 24.8: 54.4: 3.6: 0.7 (mass ratio), raw materials were prepared.

[0112] Secondly, take clean 1000ml three-necked flask and stirring paddle, etc., dry for standby, check the oil bath heating system. Weigh 165.0g of TDI-80, 248.0g of HMDI and 0.15g of IOAP, and add to the dry three-necked flask, continue to stir (speed about 150rpm) for 15min at 20±2℃, so as to fully mix, standby. Weigh 544.0g of PTMEG-1000, and add to the flask, and continue to stir (speed about 220rpm), ensure that the reaction mixture temperature ≤85℃ during the addition, after the end of the addition, maintain the reaction temperature 70±2℃. About 2h after (PTMEG-1000 addition end start), add 36.0g of DEG and 7.0g of 1,3-BG to the flask, and maintain the reaction temperature 70±2℃, about 3h after (DEG addition end start), add 0.28g of 5132 to the flask. About 4h after (DEG addition end start), determine the NCO content, test to be 7.7±0.2%, that is, the reaction endpoint is reached.

[0113] Finally, vacuum degassing the prepolymer A for 0.5h, seal, standby.

[0114] Preparation of prepolymer A-(2-9):

[0115] The preparation method is the same as that of prepolymer A-1, and the synthesis formula is shown in Table 1, wherein the percentages of TDI, HMDI, PTMEG-1000, DEG, 1,3-BG and 5132 refer to the proportions of each in the sum of the mass of the six raw materials; the percentage of IOAP refers to the proportion of it in the sum of the mass of TDI, HMDI, PTMEG-1000, DEG and 1,3-BG.

[0116] Table 1 Formula composition of prepolymer A-(1-9)

[0117]

[0118] Example 1

[0119] Preparation of reactive mixture:

[0120] Firstly, according to the basic ratio of example 1 in table 2, PEG-1000A / MOCA = 22.2 / 27.1 to form the curing agent B. The specific steps are as follows: take clean 1000ml three-necked flask and stirring paddle, etc., dry for standby; place the solid MOCA in a 120℃ oven to heat and melt into liquid for standby; weigh 222 grams of PEG-1000A into the three-necked flask, maintain the material temperature about 100℃, and continuously stir at about 100rpm; add 271 grams of standby liquid MOCA to the three-necked flask, continuously stir for more than 30min, and get uniform and stable curing agent component B.

[0121] Take 402.0 g of polyurethane prepolymer A-1 and place it in a 55°C oven for standby.

[0122] Then, take 0.12 g of KMP-702 and add it to the prepolymer A-1, mix for 30 min at 100 rpm to obtain a uniform mixture, then add 198 g of curing agent B to the above mixture and stir with a round disc-shaped paddle at 600 rpm for 2 min, then quickly inject it into an aluminum mold with a size of length * width * height = 152.4 * 76.2 * 76.2 mm, and the inner wall of the mold cavity is coated with a Teflon lining; place the mold in a vacuum oven at 80°C and stay for 10 min under a relative vacuum of -100 KPa.

[0123] Finally, the vacuum degassed molding is left in a temperature atmosphere of 105°C for 16 h to complete the curing.

[0124] The sample prepared in Example 1 is tested for hardness and modulus as follows:

[0125] Hardness: A Japanese TECLOCK Shore D hardness tester is used according to GB / T 531.1-2008.

[0126] Storage modulus (E’): quantitatively characterizes the ability of a polyurethane elastomer material to exhibit elastic behavior in response to an applied deformation, which is measured by a model DMA861e (METTLER company) in shear mode at a frequency of 1 Hz and a temperature rise rate of 3°C / min.

[0127] It is measured that the sample prepared in Example 1 has a hardness of 48D at 24°C, and the values of E’ at 40°C and 50°C are 79.2 and 66.6 MPa, respectively.

[0128] Examples 2-18

[0129] Referring to Example 1, the preparation of the reactive mixture, curing and physical property test results of Examples 2-18 are shown in Table 2.

[0130] Comparative Examples 1 and 2 are two commercialized products applied in the industry, and Comparative Example 3 is a window material disclosed in CN 112574386B.

[0131] The window materials in the listed Comparative Examples 1-3 have approximately the same raw material composition, but are different from the raw material composition described in the present application. Comparative Examples are polyurethane window materials formed from toluene diisocyanate (TDI), cyclohexylmethane diisocyanate (HMDI, which has a content of <12 wt% in the prepolymer) and polytetramethylene glycol (PTMEG), diethylene glycol (DEG), and 3,3'-dichloro-4,4'-diphenyl methane diamine (MOCA).

[0132] Comparative Examples 4-9 are obtained from compositions not containing the polysiloxane microsphere component C, as compared to Examples 1-18.

[0133] Table 2 Compositions and physical properties of the reactive mixtures of Examples 1-18

[0134]

[0135]

[0136] In the present application, the use of compositions containing polyurethane prepolymer component A, curing agent component B and polysiloxane microsphere component C, and the resulting polishing pad window materials by controlling the ratio of each component, have adjustable hardness and dynamic mechanical properties, etc., and will have higher matching with polishing pads of different properties. Conversely, the hardness and dynamic mechanical properties of the window materials of Comparative Examples 1, 2 and 3 are limited in the range of adjustment.

[0137] The samples prepared in Examples 1-18 are cut and milled on a CNC machine to form a cuboid with a length of about 57 mm, a width of about 19 mm and a height of 40 mm; further processing is carried out to form a chemical mechanical polishing layer with an integral window, which has different surface roughness according to application requirements.

[0138] In the present application, the test method for window light transmittance is as follows:

[0139] First, in the light transmittance test equipment configured with a fiber optic spectrometer of 360-1100 nm and a 360-2500 nm tungsten halogen lamp light source, the noise of the test equipment and the environment is removed in advance; then, the polishing layer containing the integral window is placed on the test system support, and the position of the polishing layer is adjusted so that the light incident through the collimating lens is transmitted through the middle of the window, the transmitted light is received by the collimating lens and coupled to the spectrometer through the optical fiber, thereby measuring the single transmittance in the range of 360-1100 nm, as shown in Table 3; the test equipment is reconfigured for double transmittance testing, which includes selecting a reflective optical fiber (6V1 bifurcated optical fiber) instead of a transmissive optical fiber, which is connected to the fiber optic spectrometer and the light source, respectively, and the reflective optical fiber probe is placed directly below the integral window on the test system support; a silicon die is selected and placed on the integral window, thereby measuring the double transmittance in the range of 360-1100 nm, as shown in Table 3.

[0140] Table 3 Light transmittance of integral windows with certain roughness

[0141]

[0142]

[0143] In the present application, the window material obtained from the composition comprising polyurethane prepolymer component A, curing agent component B and polysiloxane microsphere component C, after further pouring, curing, slicing and sanding, the finished polishing pad window containing the integral window, the window surface at a certain roughness (Ra≤10 microns), the single and double transmittance of the light at a wavelength of about 630 nm is significantly better than that of Comparative Examples 1-3; in addition, the polishing pad window obtained from the composition without polysiloxane microsphere component C also has poor double transmittance relative to the polishing pad window of the present application.

[0144] Those skilled in the art can understand that, under the teaching of the present specification, some modifications or adjustments can be made to the present application. These modifications or adjustments should also be within the scope defined by the claims of the present application.

Claims

1. A chemical mechanical polishing pad window, characterized by, The window material is prepared from a composition comprising a polyurethane prepolymer component A, a curing agent component B, and a polysiloxane microsphere component C; The hardness of the window material is 45-75D, and the surface roughness (Ra) of the chemical mechanical polishing pad window is ≤10 microns; The polyurethane prepolymer component A is a reaction product of the following components: (A1) 14.0-20.0 wt% of toluene diisocyanate (TDI) and 20.0-38.0 wt% of dicyclohexylmethane diisocyanate (HMDI); (A2) 39.0-57.0 wt% of polytetramethylene ether glycol; (A3) 3.0-9.0 wt% of small molecule diol; The curing agent component B is a mixture comprising at least the following components, (B1) 40-70 wt% of aromatic diamine chain extender; (B2) 30-60 wt% of polyethylene oxide diol; The polysiloxane microsphere component C has a particle size of 0.2-8.0 microns and a refractive index of 1.40-1.

46. The addition amount of the polysiloxane microsphere component C in the polyurethane prepolymer component A is 0.01-0.1 wt%.

2. The chemical mechanical polishing pad window of claim 1, wherein, The polyurethane prepolymer component A is a reaction product of the following components: (A1) 15.5-18.5 wt% of toluene diisocyanate (TDI) and 22.0-35.5 wt% of dicyclohexylmethane diisocyanate (HMDI); the toluene diisocyanate is a mixture of 2,4-TDI and 2,6-TDI, wherein the content of 2,4-TDI is 80-100%; the content of 2,4-HMDI in the dicyclohexylmethane diisocyanate is 6-10%; (A2) 42.0-55.0 wt% of polytetramethylene ether glycol; (A3) 4.0-7.5 wt% of small molecule diol.

3. The chemical mechanical polishing pad window of claim 2, wherein, The polytetramethylene ether glycol has a molecular weight of 650-1500.

4. The chemical mechanical polishing pad window of claim 3, wherein, The polytetramethylene ether glycol has a molecular weight of 1000.

5. The chemical mechanical polishing pad window of claim 2, wherein, The small molecule diol has a molecular weight of less than 200.

6. The chemical mechanical polishing pad window of claim 5, wherein, The small molecule diol is selected from one or more of ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propanediol, 1,3-propanediol, dipropylene glycol, tripropylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, or 1,6-hexanediol.

7. The chemical mechanical polishing pad window of claim 6, wherein, The small molecule diol is diethylene glycol, 1,3-butanediol, or a mixture thereof.

8. The chemical mechanical polishing pad window of any of claims 1-7, wherein, The polyurethane prepolymer component A is a reaction product of the reaction components under continuous stirring, with a reaction temperature of 40-100°C and a reaction time of 4-12 h; the isocyanate group (NCO) content of the polyurethane prepolymer component A is 7.0-10.0 wt%.

9. The chemical mechanical polishing pad window of claim 8, wherein, The isocyanate group (NCO) content of the polyurethane prepolymer component A is 7.5-9.5 wt%.

10. The chemical mechanical polishing pad window of claim 8, wherein, The polyurethane prepolymer component A comprises at least one liquid polybutadiene component, with a content of 0.1-0.6 wt%.

11. The chemical mechanical polishing pad window of claim 10, wherein, The content of the liquid polybutadiene component is 0.2-0.4 wt%.

12. The chemical mechanical polishing pad window of claim 1, wherein, The curing agent component B is a homogeneous, stable mixture formed by at least the following components: (B1) 55-65 wt% of aromatic diamine chain extender; (B2) 35-45 wt% of polyoxyethylene glycol.

13. The chemical mechanical polishing pad window of claim 12, wherein, The aromatic diamine chain extender comprises at least one or more of 3,3'- dichloro-4,4'-diphenylmethane diamine (MOCA), 3,5-dimethylthio-toluene diamine (DMTDA), 3,5-diethyl-toluene diamine (DETDA), 4,4'-methylenebis(3-chloro-2,6- diethyl aniline) (M-CDEA), 4,4'-methylenebis(2,6-diethyl aniline) (M-DEA), and 1,3- propanediol bis(4-aminobenzoate) (740M).

14. The chemical mechanical polishing pad window of claim 13, wherein, The aromatic diamine chain extender is MOCA or a mixture of MOCA and M-CDEA.

15. The chemical mechanical polishing pad window of claim 12, wherein, The polyoxyethylene glycol (B2) has a relative molecular mass of 600-1500.

16. The chemical mechanical polishing pad window of claim 15, wherein, The polyoxyethylene glycol (B2) has a relative molecular mass of 1000.

17. The chemical mechanical polishing pad window of claim 1 or 12, wherein, The curing agent component B is a homogeneous, stable mixture formed by at least the aromatic diamine chain extender and polyoxyethylene glycol components under a material temperature of 60-110°C with continuous stirring.

18. The chemical mechanical polishing pad window of claim 1, wherein, The polysiloxane microsphere component C has a particle size of 1.0-6.0 microns and a refractive index of 1.42-1.

45.

19. The chemical mechanical polishing pad window of claim 18, wherein, The polysiloxane microsphere component C is added to the polyurethane prepolymer component A in an amount of 0.03-0.06 wt%.

20. A method of making a chemical mechanical polishing pad window according to any one of claims 1 to 19, characterized by, Prepared by the following steps: Step 1, providing a polyurethane composition comprising at least: a polyurethane prepolymer component A, a curing agent component B, and a polysiloxane microsphere component C; Step 2, forming a reactive mixture of the polyurethane prepolymer component A, the curing agent component B, and the polysiloxane microsphere component C; Step 3, subjecting the reactive mixture to a vacuum degassing process; Step 4, subjecting the reactive mixture to a curing process.

21. The method of claim 20, wherein the chemical mechanical polishing pad window is prepared by: The stoichiometric ratio of the reactive groups of the curing agent component B and the polyurethane prepolymer component A (i.e. ([OH]+[NH2]) / [NCO]) is 0.8-1.

0.

22. The method of claim 20, wherein the chemical mechanical polishing pad window is prepared by: The vacuum degassing process is injecting the reactive mixture into a mold and leaving it under a relative vacuum of no more than -99 KPa for 6-20 min.

23. The method of claim 22, wherein the chemical mechanical polishing pad window is prepared by: The curing process is leaving the reactive mixture under a temperature atmosphere of 80-120°C for 12-48 h.

24. The method of claim 23, wherein the chemical mechanical polishing pad window is prepared by: The curing process is leaving the reactive mixture under a temperature atmosphere of 95-115°C for 16-24 h.

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